xref: /netbsd-src/external/bsd/zstd/dist/lib/legacy/zstd_v04.c (revision 3117ece4fc4a4ca4489ba793710b60b0d26bab6c)
1*3117ece4Schristos /*
2*3117ece4Schristos  * Copyright (c) Yann Collet, Meta Platforms, Inc. and affiliates.
3*3117ece4Schristos  * All rights reserved.
4*3117ece4Schristos  *
5*3117ece4Schristos  * This source code is licensed under both the BSD-style license (found in the
6*3117ece4Schristos  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7*3117ece4Schristos  * in the COPYING file in the root directory of this source tree).
8*3117ece4Schristos  * You may select, at your option, one of the above-listed licenses.
9*3117ece4Schristos  */
10*3117ece4Schristos 
11*3117ece4Schristos 
12*3117ece4Schristos  /******************************************
13*3117ece4Schristos  *  Includes
14*3117ece4Schristos  ******************************************/
15*3117ece4Schristos #include <stddef.h>    /* size_t, ptrdiff_t */
16*3117ece4Schristos #include <string.h>    /* memcpy */
17*3117ece4Schristos 
18*3117ece4Schristos #include "zstd_v04.h"
19*3117ece4Schristos #include "../common/compiler.h"
20*3117ece4Schristos #include "../common/error_private.h"
21*3117ece4Schristos 
22*3117ece4Schristos 
23*3117ece4Schristos /* ******************************************************************
24*3117ece4Schristos  *   mem.h
25*3117ece4Schristos  *******************************************************************/
26*3117ece4Schristos #ifndef MEM_H_MODULE
27*3117ece4Schristos #define MEM_H_MODULE
28*3117ece4Schristos 
29*3117ece4Schristos #if defined (__cplusplus)
30*3117ece4Schristos extern "C" {
31*3117ece4Schristos #endif
32*3117ece4Schristos 
33*3117ece4Schristos 
34*3117ece4Schristos /******************************************
35*3117ece4Schristos *  Compiler-specific
36*3117ece4Schristos ******************************************/
37*3117ece4Schristos #if defined(_MSC_VER)   /* Visual Studio */
38*3117ece4Schristos #   include <stdlib.h>  /* _byteswap_ulong */
39*3117ece4Schristos #   include <intrin.h>  /* _byteswap_* */
40*3117ece4Schristos #endif
41*3117ece4Schristos 
42*3117ece4Schristos 
43*3117ece4Schristos /****************************************************************
44*3117ece4Schristos *  Basic Types
45*3117ece4Schristos *****************************************************************/
46*3117ece4Schristos #if defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
47*3117ece4Schristos # if defined(_AIX)
48*3117ece4Schristos #  include <inttypes.h>
49*3117ece4Schristos # else
50*3117ece4Schristos #  include <stdint.h> /* intptr_t */
51*3117ece4Schristos # endif
52*3117ece4Schristos   typedef  uint8_t BYTE;
53*3117ece4Schristos   typedef uint16_t U16;
54*3117ece4Schristos   typedef  int16_t S16;
55*3117ece4Schristos   typedef uint32_t U32;
56*3117ece4Schristos   typedef  int32_t S32;
57*3117ece4Schristos   typedef uint64_t U64;
58*3117ece4Schristos   typedef  int64_t S64;
59*3117ece4Schristos #else
60*3117ece4Schristos   typedef unsigned char       BYTE;
61*3117ece4Schristos   typedef unsigned short      U16;
62*3117ece4Schristos   typedef   signed short      S16;
63*3117ece4Schristos   typedef unsigned int        U32;
64*3117ece4Schristos   typedef   signed int        S32;
65*3117ece4Schristos   typedef unsigned long long  U64;
66*3117ece4Schristos   typedef   signed long long  S64;
67*3117ece4Schristos #endif
68*3117ece4Schristos 
69*3117ece4Schristos 
70*3117ece4Schristos /*-*************************************
71*3117ece4Schristos *  Debug
72*3117ece4Schristos ***************************************/
73*3117ece4Schristos #include "../common/debug.h"
74*3117ece4Schristos #ifndef assert
75*3117ece4Schristos #  define assert(condition) ((void)0)
76*3117ece4Schristos #endif
77*3117ece4Schristos 
78*3117ece4Schristos 
79*3117ece4Schristos /****************************************************************
80*3117ece4Schristos *  Memory I/O
81*3117ece4Schristos *****************************************************************/
82*3117ece4Schristos 
83*3117ece4Schristos MEM_STATIC unsigned MEM_32bits(void) { return sizeof(void*)==4; }
84*3117ece4Schristos MEM_STATIC unsigned MEM_64bits(void) { return sizeof(void*)==8; }
85*3117ece4Schristos 
86*3117ece4Schristos MEM_STATIC unsigned MEM_isLittleEndian(void)
87*3117ece4Schristos {
88*3117ece4Schristos     const union { U32 u; BYTE c[4]; } one = { 1 };   /* don't use static : performance detrimental  */
89*3117ece4Schristos     return one.c[0];
90*3117ece4Schristos }
91*3117ece4Schristos 
92*3117ece4Schristos MEM_STATIC U16 MEM_read16(const void* memPtr)
93*3117ece4Schristos {
94*3117ece4Schristos     U16 val; memcpy(&val, memPtr, sizeof(val)); return val;
95*3117ece4Schristos }
96*3117ece4Schristos 
97*3117ece4Schristos MEM_STATIC U32 MEM_read32(const void* memPtr)
98*3117ece4Schristos {
99*3117ece4Schristos     U32 val; memcpy(&val, memPtr, sizeof(val)); return val;
100*3117ece4Schristos }
101*3117ece4Schristos 
102*3117ece4Schristos MEM_STATIC U64 MEM_read64(const void* memPtr)
103*3117ece4Schristos {
104*3117ece4Schristos     U64 val; memcpy(&val, memPtr, sizeof(val)); return val;
105*3117ece4Schristos }
106*3117ece4Schristos 
107*3117ece4Schristos MEM_STATIC void MEM_write16(void* memPtr, U16 value)
108*3117ece4Schristos {
109*3117ece4Schristos     memcpy(memPtr, &value, sizeof(value));
110*3117ece4Schristos }
111*3117ece4Schristos 
112*3117ece4Schristos MEM_STATIC U16 MEM_readLE16(const void* memPtr)
113*3117ece4Schristos {
114*3117ece4Schristos     if (MEM_isLittleEndian())
115*3117ece4Schristos         return MEM_read16(memPtr);
116*3117ece4Schristos     else
117*3117ece4Schristos     {
118*3117ece4Schristos         const BYTE* p = (const BYTE*)memPtr;
119*3117ece4Schristos         return (U16)(p[0] + (p[1]<<8));
120*3117ece4Schristos     }
121*3117ece4Schristos }
122*3117ece4Schristos 
123*3117ece4Schristos MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val)
124*3117ece4Schristos {
125*3117ece4Schristos     if (MEM_isLittleEndian())
126*3117ece4Schristos     {
127*3117ece4Schristos         MEM_write16(memPtr, val);
128*3117ece4Schristos     }
129*3117ece4Schristos     else
130*3117ece4Schristos     {
131*3117ece4Schristos         BYTE* p = (BYTE*)memPtr;
132*3117ece4Schristos         p[0] = (BYTE)val;
133*3117ece4Schristos         p[1] = (BYTE)(val>>8);
134*3117ece4Schristos     }
135*3117ece4Schristos }
136*3117ece4Schristos 
137*3117ece4Schristos MEM_STATIC U32 MEM_readLE24(const void* memPtr)
138*3117ece4Schristos {
139*3117ece4Schristos     return MEM_readLE16(memPtr) + (((const BYTE*)memPtr)[2] << 16);
140*3117ece4Schristos }
141*3117ece4Schristos 
142*3117ece4Schristos MEM_STATIC U32 MEM_readLE32(const void* memPtr)
143*3117ece4Schristos {
144*3117ece4Schristos     if (MEM_isLittleEndian())
145*3117ece4Schristos         return MEM_read32(memPtr);
146*3117ece4Schristos     else
147*3117ece4Schristos     {
148*3117ece4Schristos         const BYTE* p = (const BYTE*)memPtr;
149*3117ece4Schristos         return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24));
150*3117ece4Schristos     }
151*3117ece4Schristos }
152*3117ece4Schristos 
153*3117ece4Schristos 
154*3117ece4Schristos MEM_STATIC U64 MEM_readLE64(const void* memPtr)
155*3117ece4Schristos {
156*3117ece4Schristos     if (MEM_isLittleEndian())
157*3117ece4Schristos         return MEM_read64(memPtr);
158*3117ece4Schristos     else
159*3117ece4Schristos     {
160*3117ece4Schristos         const BYTE* p = (const BYTE*)memPtr;
161*3117ece4Schristos         return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24)
162*3117ece4Schristos                      + ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56));
163*3117ece4Schristos     }
164*3117ece4Schristos }
165*3117ece4Schristos 
166*3117ece4Schristos 
167*3117ece4Schristos MEM_STATIC size_t MEM_readLEST(const void* memPtr)
168*3117ece4Schristos {
169*3117ece4Schristos     if (MEM_32bits())
170*3117ece4Schristos         return (size_t)MEM_readLE32(memPtr);
171*3117ece4Schristos     else
172*3117ece4Schristos         return (size_t)MEM_readLE64(memPtr);
173*3117ece4Schristos }
174*3117ece4Schristos 
175*3117ece4Schristos 
176*3117ece4Schristos #if defined (__cplusplus)
177*3117ece4Schristos }
178*3117ece4Schristos #endif
179*3117ece4Schristos 
180*3117ece4Schristos #endif /* MEM_H_MODULE */
181*3117ece4Schristos 
182*3117ece4Schristos /*
183*3117ece4Schristos     zstd - standard compression library
184*3117ece4Schristos     Header File for static linking only
185*3117ece4Schristos */
186*3117ece4Schristos #ifndef ZSTD_STATIC_H
187*3117ece4Schristos #define ZSTD_STATIC_H
188*3117ece4Schristos 
189*3117ece4Schristos 
190*3117ece4Schristos /* *************************************
191*3117ece4Schristos *  Types
192*3117ece4Schristos ***************************************/
193*3117ece4Schristos #define ZSTD_WINDOWLOG_ABSOLUTEMIN 11
194*3117ece4Schristos 
195*3117ece4Schristos /** from faster to stronger */
196*3117ece4Schristos typedef enum { ZSTD_fast, ZSTD_greedy, ZSTD_lazy, ZSTD_lazy2, ZSTD_btlazy2 } ZSTD_strategy;
197*3117ece4Schristos 
198*3117ece4Schristos typedef struct
199*3117ece4Schristos {
200*3117ece4Schristos     U64 srcSize;       /* optional : tells how much bytes are present in the frame. Use 0 if not known. */
201*3117ece4Schristos     U32 windowLog;     /* largest match distance : larger == more compression, more memory needed during decompression */
202*3117ece4Schristos     U32 contentLog;    /* full search segment : larger == more compression, slower, more memory (useless for fast) */
203*3117ece4Schristos     U32 hashLog;       /* dispatch table : larger == more memory, faster */
204*3117ece4Schristos     U32 searchLog;     /* nb of searches : larger == more compression, slower */
205*3117ece4Schristos     U32 searchLength;  /* size of matches : larger == faster decompression, sometimes less compression */
206*3117ece4Schristos     ZSTD_strategy strategy;
207*3117ece4Schristos } ZSTD_parameters;
208*3117ece4Schristos 
209*3117ece4Schristos typedef ZSTDv04_Dctx ZSTD_DCtx;
210*3117ece4Schristos 
211*3117ece4Schristos /* *************************************
212*3117ece4Schristos *  Advanced functions
213*3117ece4Schristos ***************************************/
214*3117ece4Schristos /** ZSTD_decompress_usingDict
215*3117ece4Schristos *   Same as ZSTD_decompressDCtx, using a Dictionary content as prefix
216*3117ece4Schristos *   Note : dict can be NULL, in which case, it's equivalent to ZSTD_decompressDCtx() */
217*3117ece4Schristos static size_t ZSTD_decompress_usingDict(ZSTD_DCtx* ctx,
218*3117ece4Schristos                                              void* dst, size_t maxDstSize,
219*3117ece4Schristos                                        const void* src, size_t srcSize,
220*3117ece4Schristos                                        const void* dict,size_t dictSize);
221*3117ece4Schristos 
222*3117ece4Schristos 
223*3117ece4Schristos /* **************************************
224*3117ece4Schristos *  Streaming functions (direct mode)
225*3117ece4Schristos ****************************************/
226*3117ece4Schristos static size_t ZSTD_resetDCtx(ZSTD_DCtx* dctx);
227*3117ece4Schristos static size_t ZSTD_getFrameParams(ZSTD_parameters* params, const void* src, size_t srcSize);
228*3117ece4Schristos static void   ZSTD_decompress_insertDictionary(ZSTD_DCtx* ctx, const void* src, size_t srcSize);
229*3117ece4Schristos 
230*3117ece4Schristos static size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx);
231*3117ece4Schristos static size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize);
232*3117ece4Schristos 
233*3117ece4Schristos /**
234*3117ece4Schristos   Streaming decompression, bufferless mode
235*3117ece4Schristos 
236*3117ece4Schristos   A ZSTD_DCtx object is required to track streaming operations.
237*3117ece4Schristos   Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.
238*3117ece4Schristos   A ZSTD_DCtx object can be re-used multiple times. Use ZSTD_resetDCtx() to return to fresh status.
239*3117ece4Schristos 
240*3117ece4Schristos   First operation is to retrieve frame parameters, using ZSTD_getFrameParams().
241*3117ece4Schristos   This function doesn't consume its input. It needs enough input data to properly decode the frame header.
242*3117ece4Schristos   Objective is to retrieve *params.windowlog, to know minimum amount of memory required during decoding.
243*3117ece4Schristos   Result : 0 when successful, it means the ZSTD_parameters structure has been filled.
244*3117ece4Schristos            >0 : means there is not enough data into src. Provides the expected size to successfully decode header.
245*3117ece4Schristos            errorCode, which can be tested using ZSTD_isError() (For example, if it's not a ZSTD header)
246*3117ece4Schristos 
247*3117ece4Schristos   Then, you can optionally insert a dictionary.
248*3117ece4Schristos   This operation must mimic the compressor behavior, otherwise decompression will fail or be corrupted.
249*3117ece4Schristos 
250*3117ece4Schristos   Then it's possible to start decompression.
251*3117ece4Schristos   Use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() alternatively.
252*3117ece4Schristos   ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue().
253*3117ece4Schristos   ZSTD_decompressContinue() requires this exact amount of bytes, or it will fail.
254*3117ece4Schristos   ZSTD_decompressContinue() needs previous data blocks during decompression, up to (1 << windowlog).
255*3117ece4Schristos   They should preferably be located contiguously, prior to current block. Alternatively, a round buffer is also possible.
256*3117ece4Schristos 
257*3117ece4Schristos   @result of ZSTD_decompressContinue() is the number of bytes regenerated within 'dst'.
258*3117ece4Schristos   It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header.
259*3117ece4Schristos 
260*3117ece4Schristos   A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero.
261*3117ece4Schristos   Context can then be reset to start a new decompression.
262*3117ece4Schristos */
263*3117ece4Schristos 
264*3117ece4Schristos 
265*3117ece4Schristos 
266*3117ece4Schristos 
267*3117ece4Schristos #endif  /* ZSTD_STATIC_H */
268*3117ece4Schristos 
269*3117ece4Schristos 
270*3117ece4Schristos /*
271*3117ece4Schristos     zstd_internal - common functions to include
272*3117ece4Schristos     Header File for include
273*3117ece4Schristos */
274*3117ece4Schristos #ifndef ZSTD_CCOMMON_H_MODULE
275*3117ece4Schristos #define ZSTD_CCOMMON_H_MODULE
276*3117ece4Schristos 
277*3117ece4Schristos /* *************************************
278*3117ece4Schristos *  Common macros
279*3117ece4Schristos ***************************************/
280*3117ece4Schristos #define MIN(a,b) ((a)<(b) ? (a) : (b))
281*3117ece4Schristos #define MAX(a,b) ((a)>(b) ? (a) : (b))
282*3117ece4Schristos 
283*3117ece4Schristos 
284*3117ece4Schristos /* *************************************
285*3117ece4Schristos *  Common constants
286*3117ece4Schristos ***************************************/
287*3117ece4Schristos #define ZSTD_MAGICNUMBER 0xFD2FB524   /* v0.4 */
288*3117ece4Schristos 
289*3117ece4Schristos #define KB *(1 <<10)
290*3117ece4Schristos #define MB *(1 <<20)
291*3117ece4Schristos #define GB *(1U<<30)
292*3117ece4Schristos 
293*3117ece4Schristos #define BLOCKSIZE (128 KB)                 /* define, for static allocation */
294*3117ece4Schristos 
295*3117ece4Schristos static const size_t ZSTD_blockHeaderSize = 3;
296*3117ece4Schristos static const size_t ZSTD_frameHeaderSize_min = 5;
297*3117ece4Schristos #define ZSTD_frameHeaderSize_max 5         /* define, for static allocation */
298*3117ece4Schristos 
299*3117ece4Schristos #define BIT7 128
300*3117ece4Schristos #define BIT6  64
301*3117ece4Schristos #define BIT5  32
302*3117ece4Schristos #define BIT4  16
303*3117ece4Schristos #define BIT1   2
304*3117ece4Schristos #define BIT0   1
305*3117ece4Schristos 
306*3117ece4Schristos #define IS_RAW BIT0
307*3117ece4Schristos #define IS_RLE BIT1
308*3117ece4Schristos 
309*3117ece4Schristos #define MINMATCH 4
310*3117ece4Schristos #define REPCODE_STARTVALUE 4
311*3117ece4Schristos 
312*3117ece4Schristos #define MLbits   7
313*3117ece4Schristos #define LLbits   6
314*3117ece4Schristos #define Offbits  5
315*3117ece4Schristos #define MaxML  ((1<<MLbits) - 1)
316*3117ece4Schristos #define MaxLL  ((1<<LLbits) - 1)
317*3117ece4Schristos #define MaxOff ((1<<Offbits)- 1)
318*3117ece4Schristos #define MLFSELog   10
319*3117ece4Schristos #define LLFSELog   10
320*3117ece4Schristos #define OffFSELog   9
321*3117ece4Schristos #define MaxSeq MAX(MaxLL, MaxML)
322*3117ece4Schristos 
323*3117ece4Schristos #define MIN_SEQUENCES_SIZE (2 /*seqNb*/ + 2 /*dumps*/ + 3 /*seqTables*/ + 1 /*bitStream*/)
324*3117ece4Schristos #define MIN_CBLOCK_SIZE (3 /*litCSize*/ + MIN_SEQUENCES_SIZE)
325*3117ece4Schristos 
326*3117ece4Schristos #define ZSTD_CONTENTSIZE_ERROR   (0ULL - 2)
327*3117ece4Schristos 
328*3117ece4Schristos typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t;
329*3117ece4Schristos 
330*3117ece4Schristos 
331*3117ece4Schristos /* ******************************************
332*3117ece4Schristos *  Shared functions to include for inlining
333*3117ece4Schristos ********************************************/
334*3117ece4Schristos static void ZSTD_copy8(void* dst, const void* src) { memcpy(dst, src, 8); }
335*3117ece4Schristos 
336*3117ece4Schristos #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
337*3117ece4Schristos 
338*3117ece4Schristos /*! ZSTD_wildcopy : custom version of memcpy(), can copy up to 7-8 bytes too many */
339*3117ece4Schristos static void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length)
340*3117ece4Schristos {
341*3117ece4Schristos     const BYTE* ip = (const BYTE*)src;
342*3117ece4Schristos     BYTE* op = (BYTE*)dst;
343*3117ece4Schristos     BYTE* const oend = op + length;
344*3117ece4Schristos     do
345*3117ece4Schristos         COPY8(op, ip)
346*3117ece4Schristos     while (op < oend);
347*3117ece4Schristos }
348*3117ece4Schristos 
349*3117ece4Schristos 
350*3117ece4Schristos 
351*3117ece4Schristos /* ******************************************************************
352*3117ece4Schristos    FSE : Finite State Entropy coder
353*3117ece4Schristos    header file
354*3117ece4Schristos ****************************************************************** */
355*3117ece4Schristos #ifndef FSE_H
356*3117ece4Schristos #define FSE_H
357*3117ece4Schristos 
358*3117ece4Schristos #if defined (__cplusplus)
359*3117ece4Schristos extern "C" {
360*3117ece4Schristos #endif
361*3117ece4Schristos 
362*3117ece4Schristos 
363*3117ece4Schristos /* *****************************************
364*3117ece4Schristos *  Includes
365*3117ece4Schristos ******************************************/
366*3117ece4Schristos #include <stddef.h>    /* size_t, ptrdiff_t */
367*3117ece4Schristos 
368*3117ece4Schristos 
369*3117ece4Schristos /* *****************************************
370*3117ece4Schristos *  FSE simple functions
371*3117ece4Schristos ******************************************/
372*3117ece4Schristos static size_t FSE_decompress(void* dst,  size_t maxDstSize,
373*3117ece4Schristos                 const void* cSrc, size_t cSrcSize);
374*3117ece4Schristos /*!
375*3117ece4Schristos FSE_decompress():
376*3117ece4Schristos     Decompress FSE data from buffer 'cSrc', of size 'cSrcSize',
377*3117ece4Schristos     into already allocated destination buffer 'dst', of size 'maxDstSize'.
378*3117ece4Schristos     return : size of regenerated data (<= maxDstSize)
379*3117ece4Schristos              or an error code, which can be tested using FSE_isError()
380*3117ece4Schristos 
381*3117ece4Schristos     ** Important ** : FSE_decompress() doesn't decompress non-compressible nor RLE data !!!
382*3117ece4Schristos     Why ? : making this distinction requires a header.
383*3117ece4Schristos     Header management is intentionally delegated to the user layer, which can better manage special cases.
384*3117ece4Schristos */
385*3117ece4Schristos 
386*3117ece4Schristos 
387*3117ece4Schristos /* *****************************************
388*3117ece4Schristos *  Tool functions
389*3117ece4Schristos ******************************************/
390*3117ece4Schristos /* Error Management */
391*3117ece4Schristos static unsigned    FSE_isError(size_t code);        /* tells if a return value is an error code */
392*3117ece4Schristos 
393*3117ece4Schristos 
394*3117ece4Schristos 
395*3117ece4Schristos /* *****************************************
396*3117ece4Schristos *  FSE detailed API
397*3117ece4Schristos ******************************************/
398*3117ece4Schristos /*!
399*3117ece4Schristos FSE_compress() does the following:
400*3117ece4Schristos 1. count symbol occurrence from source[] into table count[]
401*3117ece4Schristos 2. normalize counters so that sum(count[]) == Power_of_2 (2^tableLog)
402*3117ece4Schristos 3. save normalized counters to memory buffer using writeNCount()
403*3117ece4Schristos 4. build encoding table 'CTable' from normalized counters
404*3117ece4Schristos 5. encode the data stream using encoding table 'CTable'
405*3117ece4Schristos 
406*3117ece4Schristos FSE_decompress() does the following:
407*3117ece4Schristos 1. read normalized counters with readNCount()
408*3117ece4Schristos 2. build decoding table 'DTable' from normalized counters
409*3117ece4Schristos 3. decode the data stream using decoding table 'DTable'
410*3117ece4Schristos 
411*3117ece4Schristos The following API allows targeting specific sub-functions for advanced tasks.
412*3117ece4Schristos For example, it's possible to compress several blocks using the same 'CTable',
413*3117ece4Schristos or to save and provide normalized distribution using external method.
414*3117ece4Schristos */
415*3117ece4Schristos 
416*3117ece4Schristos 
417*3117ece4Schristos /* *** DECOMPRESSION *** */
418*3117ece4Schristos 
419*3117ece4Schristos /*!
420*3117ece4Schristos FSE_readNCount():
421*3117ece4Schristos    Read compactly saved 'normalizedCounter' from 'rBuffer'.
422*3117ece4Schristos    return : size read from 'rBuffer'
423*3117ece4Schristos             or an errorCode, which can be tested using FSE_isError()
424*3117ece4Schristos             maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */
425*3117ece4Schristos static  size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSymbolValuePtr, unsigned* tableLogPtr, const void* rBuffer, size_t rBuffSize);
426*3117ece4Schristos 
427*3117ece4Schristos /*!
428*3117ece4Schristos Constructor and Destructor of type FSE_DTable
429*3117ece4Schristos     Note that its size depends on 'tableLog' */
430*3117ece4Schristos typedef unsigned FSE_DTable;   /* don't allocate that. It's just a way to be more restrictive than void* */
431*3117ece4Schristos 
432*3117ece4Schristos /*!
433*3117ece4Schristos FSE_buildDTable():
434*3117ece4Schristos    Builds 'dt', which must be already allocated, using FSE_createDTable()
435*3117ece4Schristos    return : 0,
436*3117ece4Schristos             or an errorCode, which can be tested using FSE_isError() */
437*3117ece4Schristos static size_t FSE_buildDTable ( FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog);
438*3117ece4Schristos 
439*3117ece4Schristos /*!
440*3117ece4Schristos FSE_decompress_usingDTable():
441*3117ece4Schristos    Decompress compressed source 'cSrc' of size 'cSrcSize' using 'dt'
442*3117ece4Schristos    into 'dst' which must be already allocated.
443*3117ece4Schristos    return : size of regenerated data (necessarily <= maxDstSize)
444*3117ece4Schristos             or an errorCode, which can be tested using FSE_isError() */
445*3117ece4Schristos static  size_t FSE_decompress_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const FSE_DTable* dt);
446*3117ece4Schristos 
447*3117ece4Schristos /*!
448*3117ece4Schristos Tutorial :
449*3117ece4Schristos ----------
450*3117ece4Schristos (Note : these functions only decompress FSE-compressed blocks.
451*3117ece4Schristos  If block is uncompressed, use memcpy() instead
452*3117ece4Schristos  If block is a single repeated byte, use memset() instead )
453*3117ece4Schristos 
454*3117ece4Schristos The first step is to obtain the normalized frequencies of symbols.
455*3117ece4Schristos This can be performed by FSE_readNCount() if it was saved using FSE_writeNCount().
456*3117ece4Schristos 'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short.
457*3117ece4Schristos In practice, that means it's necessary to know 'maxSymbolValue' beforehand,
458*3117ece4Schristos or size the table to handle worst case situations (typically 256).
459*3117ece4Schristos FSE_readNCount() will provide 'tableLog' and 'maxSymbolValue'.
460*3117ece4Schristos The result of FSE_readNCount() is the number of bytes read from 'rBuffer'.
461*3117ece4Schristos Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that.
462*3117ece4Schristos If there is an error, the function will return an error code, which can be tested using FSE_isError().
463*3117ece4Schristos 
464*3117ece4Schristos The next step is to build the decompression tables 'FSE_DTable' from 'normalizedCounter'.
465*3117ece4Schristos This is performed by the function FSE_buildDTable().
466*3117ece4Schristos The space required by 'FSE_DTable' must be already allocated using FSE_createDTable().
467*3117ece4Schristos If there is an error, the function will return an error code, which can be tested using FSE_isError().
468*3117ece4Schristos 
469*3117ece4Schristos 'FSE_DTable' can then be used to decompress 'cSrc', with FSE_decompress_usingDTable().
470*3117ece4Schristos 'cSrcSize' must be strictly correct, otherwise decompression will fail.
471*3117ece4Schristos FSE_decompress_usingDTable() result will tell how many bytes were regenerated (<=maxDstSize).
472*3117ece4Schristos If there is an error, the function will return an error code, which can be tested using FSE_isError(). (ex: dst buffer too small)
473*3117ece4Schristos */
474*3117ece4Schristos 
475*3117ece4Schristos 
476*3117ece4Schristos #if defined (__cplusplus)
477*3117ece4Schristos }
478*3117ece4Schristos #endif
479*3117ece4Schristos 
480*3117ece4Schristos #endif  /* FSE_H */
481*3117ece4Schristos 
482*3117ece4Schristos 
483*3117ece4Schristos /* ******************************************************************
484*3117ece4Schristos    bitstream
485*3117ece4Schristos    Part of NewGen Entropy library
486*3117ece4Schristos    header file (to include)
487*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet.
488*3117ece4Schristos 
489*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
490*3117ece4Schristos 
491*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
492*3117ece4Schristos    modification, are permitted provided that the following conditions are
493*3117ece4Schristos    met:
494*3117ece4Schristos 
495*3117ece4Schristos        * Redistributions of source code must retain the above copyright
496*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
497*3117ece4Schristos        * Redistributions in binary form must reproduce the above
498*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
499*3117ece4Schristos    in the documentation and/or other materials provided with the
500*3117ece4Schristos    distribution.
501*3117ece4Schristos 
502*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
503*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
504*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
505*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
506*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
507*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
508*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
509*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
510*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
511*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
512*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
513*3117ece4Schristos 
514*3117ece4Schristos    You can contact the author at :
515*3117ece4Schristos    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
516*3117ece4Schristos    - Public forum : https://groups.google.com/forum/#!forum/lz4c
517*3117ece4Schristos ****************************************************************** */
518*3117ece4Schristos #ifndef BITSTREAM_H_MODULE
519*3117ece4Schristos #define BITSTREAM_H_MODULE
520*3117ece4Schristos 
521*3117ece4Schristos #if defined (__cplusplus)
522*3117ece4Schristos extern "C" {
523*3117ece4Schristos #endif
524*3117ece4Schristos 
525*3117ece4Schristos 
526*3117ece4Schristos /*
527*3117ece4Schristos *  This API consists of small unitary functions, which highly benefit from being inlined.
528*3117ece4Schristos *  Since link-time-optimization is not available for all compilers,
529*3117ece4Schristos *  these functions are defined into a .h to be included.
530*3117ece4Schristos */
531*3117ece4Schristos 
532*3117ece4Schristos /**********************************************
533*3117ece4Schristos *  bitStream decompression API (read backward)
534*3117ece4Schristos **********************************************/
535*3117ece4Schristos typedef struct
536*3117ece4Schristos {
537*3117ece4Schristos     size_t   bitContainer;
538*3117ece4Schristos     unsigned bitsConsumed;
539*3117ece4Schristos     const char* ptr;
540*3117ece4Schristos     const char* start;
541*3117ece4Schristos } BIT_DStream_t;
542*3117ece4Schristos 
543*3117ece4Schristos typedef enum { BIT_DStream_unfinished = 0,
544*3117ece4Schristos                BIT_DStream_endOfBuffer = 1,
545*3117ece4Schristos                BIT_DStream_completed = 2,
546*3117ece4Schristos                BIT_DStream_overflow = 3 } BIT_DStream_status;  /* result of BIT_reloadDStream() */
547*3117ece4Schristos                /* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */
548*3117ece4Schristos 
549*3117ece4Schristos MEM_STATIC size_t   BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, size_t srcSize);
550*3117ece4Schristos MEM_STATIC size_t   BIT_readBits(BIT_DStream_t* bitD, unsigned nbBits);
551*3117ece4Schristos MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD);
552*3117ece4Schristos MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* bitD);
553*3117ece4Schristos 
554*3117ece4Schristos 
555*3117ece4Schristos 
556*3117ece4Schristos 
557*3117ece4Schristos /******************************************
558*3117ece4Schristos *  unsafe API
559*3117ece4Schristos ******************************************/
560*3117ece4Schristos MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits);
561*3117ece4Schristos /* faster, but works only if nbBits >= 1 */
562*3117ece4Schristos 
563*3117ece4Schristos 
564*3117ece4Schristos 
565*3117ece4Schristos /****************************************************************
566*3117ece4Schristos *  Helper functions
567*3117ece4Schristos ****************************************************************/
568*3117ece4Schristos MEM_STATIC unsigned BIT_highbit32 (U32 val)
569*3117ece4Schristos {
570*3117ece4Schristos #   if defined(_MSC_VER)   /* Visual */
571*3117ece4Schristos     unsigned long r;
572*3117ece4Schristos     return _BitScanReverse(&r, val) ? (unsigned)r : 0;
573*3117ece4Schristos #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */
574*3117ece4Schristos     return __builtin_clz (val) ^ 31;
575*3117ece4Schristos #   else   /* Software version */
576*3117ece4Schristos     static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 };
577*3117ece4Schristos     U32 v = val;
578*3117ece4Schristos     unsigned r;
579*3117ece4Schristos     v |= v >> 1;
580*3117ece4Schristos     v |= v >> 2;
581*3117ece4Schristos     v |= v >> 4;
582*3117ece4Schristos     v |= v >> 8;
583*3117ece4Schristos     v |= v >> 16;
584*3117ece4Schristos     r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27];
585*3117ece4Schristos     return r;
586*3117ece4Schristos #   endif
587*3117ece4Schristos }
588*3117ece4Schristos 
589*3117ece4Schristos 
590*3117ece4Schristos /**********************************************************
591*3117ece4Schristos * bitStream decoding
592*3117ece4Schristos **********************************************************/
593*3117ece4Schristos 
594*3117ece4Schristos /*!BIT_initDStream
595*3117ece4Schristos *  Initialize a BIT_DStream_t.
596*3117ece4Schristos *  @bitD : a pointer to an already allocated BIT_DStream_t structure
597*3117ece4Schristos *  @srcBuffer must point at the beginning of a bitStream
598*3117ece4Schristos *  @srcSize must be the exact size of the bitStream
599*3117ece4Schristos *  @result : size of stream (== srcSize) or an errorCode if a problem is detected
600*3117ece4Schristos */
601*3117ece4Schristos MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, size_t srcSize)
602*3117ece4Schristos {
603*3117ece4Schristos     if (srcSize < 1) { memset(bitD, 0, sizeof(*bitD)); return ERROR(srcSize_wrong); }
604*3117ece4Schristos 
605*3117ece4Schristos     if (srcSize >=  sizeof(size_t))   /* normal case */
606*3117ece4Schristos     {
607*3117ece4Schristos         U32 contain32;
608*3117ece4Schristos         bitD->start = (const char*)srcBuffer;
609*3117ece4Schristos         bitD->ptr   = (const char*)srcBuffer + srcSize - sizeof(size_t);
610*3117ece4Schristos         bitD->bitContainer = MEM_readLEST(bitD->ptr);
611*3117ece4Schristos         contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
612*3117ece4Schristos         if (contain32 == 0) return ERROR(GENERIC);   /* endMark not present */
613*3117ece4Schristos         bitD->bitsConsumed = 8 - BIT_highbit32(contain32);
614*3117ece4Schristos     }
615*3117ece4Schristos     else
616*3117ece4Schristos     {
617*3117ece4Schristos         U32 contain32;
618*3117ece4Schristos         bitD->start = (const char*)srcBuffer;
619*3117ece4Schristos         bitD->ptr   = bitD->start;
620*3117ece4Schristos         bitD->bitContainer = *(const BYTE*)(bitD->start);
621*3117ece4Schristos         switch(srcSize)
622*3117ece4Schristos         {
623*3117ece4Schristos             case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);/* fall-through */
624*3117ece4Schristos             case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);/* fall-through */
625*3117ece4Schristos             case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);/* fall-through */
626*3117ece4Schristos             case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24; /* fall-through */
627*3117ece4Schristos             case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16; /* fall-through */
628*3117ece4Schristos             case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) <<  8; /* fall-through */
629*3117ece4Schristos             default: break;
630*3117ece4Schristos         }
631*3117ece4Schristos         contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
632*3117ece4Schristos         if (contain32 == 0) return ERROR(GENERIC);   /* endMark not present */
633*3117ece4Schristos         bitD->bitsConsumed = 8 - BIT_highbit32(contain32);
634*3117ece4Schristos         bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8;
635*3117ece4Schristos     }
636*3117ece4Schristos 
637*3117ece4Schristos     return srcSize;
638*3117ece4Schristos }
639*3117ece4Schristos 
640*3117ece4Schristos MEM_STATIC size_t BIT_lookBits(BIT_DStream_t* bitD, U32 nbBits)
641*3117ece4Schristos {
642*3117ece4Schristos     const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1;
643*3117ece4Schristos     return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask-nbBits) & bitMask);
644*3117ece4Schristos }
645*3117ece4Schristos 
646*3117ece4Schristos /*! BIT_lookBitsFast :
647*3117ece4Schristos *   unsafe version; only works if nbBits >= 1 */
648*3117ece4Schristos MEM_STATIC size_t BIT_lookBitsFast(BIT_DStream_t* bitD, U32 nbBits)
649*3117ece4Schristos {
650*3117ece4Schristos     const U32 bitMask = sizeof(bitD->bitContainer)*8 - 1;
651*3117ece4Schristos     return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask+1)-nbBits) & bitMask);
652*3117ece4Schristos }
653*3117ece4Schristos 
654*3117ece4Schristos MEM_STATIC void BIT_skipBits(BIT_DStream_t* bitD, U32 nbBits)
655*3117ece4Schristos {
656*3117ece4Schristos     bitD->bitsConsumed += nbBits;
657*3117ece4Schristos }
658*3117ece4Schristos 
659*3117ece4Schristos MEM_STATIC size_t BIT_readBits(BIT_DStream_t* bitD, U32 nbBits)
660*3117ece4Schristos {
661*3117ece4Schristos     size_t value = BIT_lookBits(bitD, nbBits);
662*3117ece4Schristos     BIT_skipBits(bitD, nbBits);
663*3117ece4Schristos     return value;
664*3117ece4Schristos }
665*3117ece4Schristos 
666*3117ece4Schristos /*!BIT_readBitsFast :
667*3117ece4Schristos *  unsafe version; only works if nbBits >= 1 */
668*3117ece4Schristos MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, U32 nbBits)
669*3117ece4Schristos {
670*3117ece4Schristos     size_t value = BIT_lookBitsFast(bitD, nbBits);
671*3117ece4Schristos     BIT_skipBits(bitD, nbBits);
672*3117ece4Schristos     return value;
673*3117ece4Schristos }
674*3117ece4Schristos 
675*3117ece4Schristos MEM_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t* bitD)
676*3117ece4Schristos {
677*3117ece4Schristos     if (bitD->bitsConsumed > (sizeof(bitD->bitContainer)*8))  /* should never happen */
678*3117ece4Schristos         return BIT_DStream_overflow;
679*3117ece4Schristos 
680*3117ece4Schristos     if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer))
681*3117ece4Schristos     {
682*3117ece4Schristos         bitD->ptr -= bitD->bitsConsumed >> 3;
683*3117ece4Schristos         bitD->bitsConsumed &= 7;
684*3117ece4Schristos         bitD->bitContainer = MEM_readLEST(bitD->ptr);
685*3117ece4Schristos         return BIT_DStream_unfinished;
686*3117ece4Schristos     }
687*3117ece4Schristos     if (bitD->ptr == bitD->start)
688*3117ece4Schristos     {
689*3117ece4Schristos         if (bitD->bitsConsumed < sizeof(bitD->bitContainer)*8) return BIT_DStream_endOfBuffer;
690*3117ece4Schristos         return BIT_DStream_completed;
691*3117ece4Schristos     }
692*3117ece4Schristos     {
693*3117ece4Schristos         U32 nbBytes = bitD->bitsConsumed >> 3;
694*3117ece4Schristos         BIT_DStream_status result = BIT_DStream_unfinished;
695*3117ece4Schristos         if (bitD->ptr - nbBytes < bitD->start)
696*3117ece4Schristos         {
697*3117ece4Schristos             nbBytes = (U32)(bitD->ptr - bitD->start);  /* ptr > start */
698*3117ece4Schristos             result = BIT_DStream_endOfBuffer;
699*3117ece4Schristos         }
700*3117ece4Schristos         bitD->ptr -= nbBytes;
701*3117ece4Schristos         bitD->bitsConsumed -= nbBytes*8;
702*3117ece4Schristos         bitD->bitContainer = MEM_readLEST(bitD->ptr);   /* reminder : srcSize > sizeof(bitD) */
703*3117ece4Schristos         return result;
704*3117ece4Schristos     }
705*3117ece4Schristos }
706*3117ece4Schristos 
707*3117ece4Schristos /*! BIT_endOfDStream
708*3117ece4Schristos *   @return Tells if DStream has reached its exact end
709*3117ece4Schristos */
710*3117ece4Schristos MEM_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t* DStream)
711*3117ece4Schristos {
712*3117ece4Schristos     return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer)*8));
713*3117ece4Schristos }
714*3117ece4Schristos 
715*3117ece4Schristos #if defined (__cplusplus)
716*3117ece4Schristos }
717*3117ece4Schristos #endif
718*3117ece4Schristos 
719*3117ece4Schristos #endif /* BITSTREAM_H_MODULE */
720*3117ece4Schristos 
721*3117ece4Schristos 
722*3117ece4Schristos 
723*3117ece4Schristos /* ******************************************************************
724*3117ece4Schristos    FSE : Finite State Entropy coder
725*3117ece4Schristos    header file for static linking (only)
726*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet
727*3117ece4Schristos 
728*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
729*3117ece4Schristos 
730*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
731*3117ece4Schristos    modification, are permitted provided that the following conditions are
732*3117ece4Schristos    met:
733*3117ece4Schristos 
734*3117ece4Schristos        * Redistributions of source code must retain the above copyright
735*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
736*3117ece4Schristos        * Redistributions in binary form must reproduce the above
737*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
738*3117ece4Schristos    in the documentation and/or other materials provided with the
739*3117ece4Schristos    distribution.
740*3117ece4Schristos 
741*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
742*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
743*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
744*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
745*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
746*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
747*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
748*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
749*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
750*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
751*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
752*3117ece4Schristos 
753*3117ece4Schristos    You can contact the author at :
754*3117ece4Schristos    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
755*3117ece4Schristos    - Public forum : https://groups.google.com/forum/#!forum/lz4c
756*3117ece4Schristos ****************************************************************** */
757*3117ece4Schristos #ifndef FSE_STATIC_H
758*3117ece4Schristos #define FSE_STATIC_H
759*3117ece4Schristos 
760*3117ece4Schristos #if defined (__cplusplus)
761*3117ece4Schristos extern "C" {
762*3117ece4Schristos #endif
763*3117ece4Schristos 
764*3117ece4Schristos 
765*3117ece4Schristos /* *****************************************
766*3117ece4Schristos *  Static allocation
767*3117ece4Schristos *******************************************/
768*3117ece4Schristos /* FSE buffer bounds */
769*3117ece4Schristos #define FSE_NCOUNTBOUND 512
770*3117ece4Schristos #define FSE_BLOCKBOUND(size) (size + (size>>7))
771*3117ece4Schristos #define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size))   /* Macro version, useful for static allocation */
772*3117ece4Schristos 
773*3117ece4Schristos /* It is possible to statically allocate FSE CTable/DTable as a table of unsigned using below macros */
774*3117ece4Schristos #define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue)   (1 + (1<<(maxTableLog-1)) + ((maxSymbolValue+1)*2))
775*3117ece4Schristos #define FSE_DTABLE_SIZE_U32(maxTableLog)                   (1 + (1<<maxTableLog))
776*3117ece4Schristos 
777*3117ece4Schristos 
778*3117ece4Schristos /* *****************************************
779*3117ece4Schristos *  FSE advanced API
780*3117ece4Schristos *******************************************/
781*3117ece4Schristos static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits);
782*3117ece4Schristos /* build a fake FSE_DTable, designed to read an uncompressed bitstream where each symbol uses nbBits */
783*3117ece4Schristos 
784*3117ece4Schristos static size_t FSE_buildDTable_rle (FSE_DTable* dt, unsigned char symbolValue);
785*3117ece4Schristos /* build a fake FSE_DTable, designed to always generate the same symbolValue */
786*3117ece4Schristos 
787*3117ece4Schristos 
788*3117ece4Schristos 
789*3117ece4Schristos /* *****************************************
790*3117ece4Schristos *  FSE symbol decompression API
791*3117ece4Schristos *******************************************/
792*3117ece4Schristos typedef struct
793*3117ece4Schristos {
794*3117ece4Schristos     size_t      state;
795*3117ece4Schristos     const void* table;   /* precise table may vary, depending on U16 */
796*3117ece4Schristos } FSE_DState_t;
797*3117ece4Schristos 
798*3117ece4Schristos 
799*3117ece4Schristos static void     FSE_initDState(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD, const FSE_DTable* dt);
800*3117ece4Schristos 
801*3117ece4Schristos static unsigned char FSE_decodeSymbol(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD);
802*3117ece4Schristos 
803*3117ece4Schristos static unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr);
804*3117ece4Schristos 
805*3117ece4Schristos 
806*3117ece4Schristos /* *****************************************
807*3117ece4Schristos *  FSE unsafe API
808*3117ece4Schristos *******************************************/
809*3117ece4Schristos static unsigned char FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD);
810*3117ece4Schristos /* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */
811*3117ece4Schristos 
812*3117ece4Schristos 
813*3117ece4Schristos /* *****************************************
814*3117ece4Schristos *  Implementation of inlined functions
815*3117ece4Schristos *******************************************/
816*3117ece4Schristos /* decompression */
817*3117ece4Schristos 
818*3117ece4Schristos typedef struct {
819*3117ece4Schristos     U16 tableLog;
820*3117ece4Schristos     U16 fastMode;
821*3117ece4Schristos } FSE_DTableHeader;   /* sizeof U32 */
822*3117ece4Schristos 
823*3117ece4Schristos typedef struct
824*3117ece4Schristos {
825*3117ece4Schristos     unsigned short newState;
826*3117ece4Schristos     unsigned char  symbol;
827*3117ece4Schristos     unsigned char  nbBits;
828*3117ece4Schristos } FSE_decode_t;   /* size == U32 */
829*3117ece4Schristos 
830*3117ece4Schristos MEM_STATIC void FSE_initDState(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD, const FSE_DTable* dt)
831*3117ece4Schristos {
832*3117ece4Schristos     FSE_DTableHeader DTableH;
833*3117ece4Schristos     memcpy(&DTableH, dt, sizeof(DTableH));
834*3117ece4Schristos     DStatePtr->state = BIT_readBits(bitD, DTableH.tableLog);
835*3117ece4Schristos     BIT_reloadDStream(bitD);
836*3117ece4Schristos     DStatePtr->table = dt + 1;
837*3117ece4Schristos }
838*3117ece4Schristos 
839*3117ece4Schristos MEM_STATIC BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD)
840*3117ece4Schristos {
841*3117ece4Schristos     const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
842*3117ece4Schristos     const U32  nbBits = DInfo.nbBits;
843*3117ece4Schristos     BYTE symbol = DInfo.symbol;
844*3117ece4Schristos     size_t lowBits = BIT_readBits(bitD, nbBits);
845*3117ece4Schristos 
846*3117ece4Schristos     DStatePtr->state = DInfo.newState + lowBits;
847*3117ece4Schristos     return symbol;
848*3117ece4Schristos }
849*3117ece4Schristos 
850*3117ece4Schristos MEM_STATIC BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, BIT_DStream_t* bitD)
851*3117ece4Schristos {
852*3117ece4Schristos     const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
853*3117ece4Schristos     const U32 nbBits = DInfo.nbBits;
854*3117ece4Schristos     BYTE symbol = DInfo.symbol;
855*3117ece4Schristos     size_t lowBits = BIT_readBitsFast(bitD, nbBits);
856*3117ece4Schristos 
857*3117ece4Schristos     DStatePtr->state = DInfo.newState + lowBits;
858*3117ece4Schristos     return symbol;
859*3117ece4Schristos }
860*3117ece4Schristos 
861*3117ece4Schristos MEM_STATIC unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr)
862*3117ece4Schristos {
863*3117ece4Schristos     return DStatePtr->state == 0;
864*3117ece4Schristos }
865*3117ece4Schristos 
866*3117ece4Schristos 
867*3117ece4Schristos #if defined (__cplusplus)
868*3117ece4Schristos }
869*3117ece4Schristos #endif
870*3117ece4Schristos 
871*3117ece4Schristos #endif  /* FSE_STATIC_H */
872*3117ece4Schristos 
873*3117ece4Schristos /* ******************************************************************
874*3117ece4Schristos    FSE : Finite State Entropy coder
875*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet.
876*3117ece4Schristos 
877*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
878*3117ece4Schristos 
879*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
880*3117ece4Schristos    modification, are permitted provided that the following conditions are
881*3117ece4Schristos    met:
882*3117ece4Schristos 
883*3117ece4Schristos        * Redistributions of source code must retain the above copyright
884*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
885*3117ece4Schristos        * Redistributions in binary form must reproduce the above
886*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
887*3117ece4Schristos    in the documentation and/or other materials provided with the
888*3117ece4Schristos    distribution.
889*3117ece4Schristos 
890*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
891*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
892*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
893*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
894*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
895*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
896*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
897*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
898*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
899*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
900*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
901*3117ece4Schristos 
902*3117ece4Schristos     You can contact the author at :
903*3117ece4Schristos     - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
904*3117ece4Schristos     - Public forum : https://groups.google.com/forum/#!forum/lz4c
905*3117ece4Schristos ****************************************************************** */
906*3117ece4Schristos 
907*3117ece4Schristos #ifndef FSE_COMMONDEFS_ONLY
908*3117ece4Schristos 
909*3117ece4Schristos /* **************************************************************
910*3117ece4Schristos *  Tuning parameters
911*3117ece4Schristos ****************************************************************/
912*3117ece4Schristos /*!MEMORY_USAGE :
913*3117ece4Schristos *  Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
914*3117ece4Schristos *  Increasing memory usage improves compression ratio
915*3117ece4Schristos *  Reduced memory usage can improve speed, due to cache effect
916*3117ece4Schristos *  Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
917*3117ece4Schristos #define FSE_MAX_MEMORY_USAGE 14
918*3117ece4Schristos #define FSE_DEFAULT_MEMORY_USAGE 13
919*3117ece4Schristos 
920*3117ece4Schristos /*!FSE_MAX_SYMBOL_VALUE :
921*3117ece4Schristos *  Maximum symbol value authorized.
922*3117ece4Schristos *  Required for proper stack allocation */
923*3117ece4Schristos #define FSE_MAX_SYMBOL_VALUE 255
924*3117ece4Schristos 
925*3117ece4Schristos 
926*3117ece4Schristos /* **************************************************************
927*3117ece4Schristos *  template functions type & suffix
928*3117ece4Schristos ****************************************************************/
929*3117ece4Schristos #define FSE_FUNCTION_TYPE BYTE
930*3117ece4Schristos #define FSE_FUNCTION_EXTENSION
931*3117ece4Schristos #define FSE_DECODE_TYPE FSE_decode_t
932*3117ece4Schristos 
933*3117ece4Schristos 
934*3117ece4Schristos #endif   /* !FSE_COMMONDEFS_ONLY */
935*3117ece4Schristos 
936*3117ece4Schristos /* **************************************************************
937*3117ece4Schristos *  Compiler specifics
938*3117ece4Schristos ****************************************************************/
939*3117ece4Schristos #ifdef _MSC_VER    /* Visual Studio */
940*3117ece4Schristos #  define FORCE_INLINE static __forceinline
941*3117ece4Schristos #  include <intrin.h>                    /* For Visual 2005 */
942*3117ece4Schristos #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
943*3117ece4Schristos #  pragma warning(disable : 4214)        /* disable: C4214: non-int bitfields */
944*3117ece4Schristos #else
945*3117ece4Schristos #  if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L   /* C99 */
946*3117ece4Schristos #    ifdef __GNUC__
947*3117ece4Schristos #      define FORCE_INLINE static inline __attribute__((always_inline))
948*3117ece4Schristos #    else
949*3117ece4Schristos #      define FORCE_INLINE static inline
950*3117ece4Schristos #    endif
951*3117ece4Schristos #  else
952*3117ece4Schristos #    define FORCE_INLINE static
953*3117ece4Schristos #  endif /* __STDC_VERSION__ */
954*3117ece4Schristos #endif
955*3117ece4Schristos 
956*3117ece4Schristos 
957*3117ece4Schristos /* **************************************************************
958*3117ece4Schristos *  Dependencies
959*3117ece4Schristos ****************************************************************/
960*3117ece4Schristos #include <stdlib.h>     /* malloc, free, qsort */
961*3117ece4Schristos #include <string.h>     /* memcpy, memset */
962*3117ece4Schristos #include <stdio.h>      /* printf (debug) */
963*3117ece4Schristos 
964*3117ece4Schristos 
965*3117ece4Schristos /* ***************************************************************
966*3117ece4Schristos *  Constants
967*3117ece4Schristos *****************************************************************/
968*3117ece4Schristos #define FSE_MAX_TABLELOG  (FSE_MAX_MEMORY_USAGE-2)
969*3117ece4Schristos #define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG)
970*3117ece4Schristos #define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1)
971*3117ece4Schristos #define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2)
972*3117ece4Schristos #define FSE_MIN_TABLELOG 5
973*3117ece4Schristos 
974*3117ece4Schristos #define FSE_TABLELOG_ABSOLUTE_MAX 15
975*3117ece4Schristos #if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX
976*3117ece4Schristos #error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported"
977*3117ece4Schristos #endif
978*3117ece4Schristos 
979*3117ece4Schristos 
980*3117ece4Schristos /* **************************************************************
981*3117ece4Schristos *  Error Management
982*3117ece4Schristos ****************************************************************/
983*3117ece4Schristos #define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
984*3117ece4Schristos 
985*3117ece4Schristos 
986*3117ece4Schristos /* **************************************************************
987*3117ece4Schristos *  Complex types
988*3117ece4Schristos ****************************************************************/
989*3117ece4Schristos typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)];
990*3117ece4Schristos 
991*3117ece4Schristos 
992*3117ece4Schristos /*-**************************************************************
993*3117ece4Schristos *  Templates
994*3117ece4Schristos ****************************************************************/
995*3117ece4Schristos /*
996*3117ece4Schristos   designed to be included
997*3117ece4Schristos   for type-specific functions (template emulation in C)
998*3117ece4Schristos   Objective is to write these functions only once, for improved maintenance
999*3117ece4Schristos */
1000*3117ece4Schristos 
1001*3117ece4Schristos /* safety checks */
1002*3117ece4Schristos #ifndef FSE_FUNCTION_EXTENSION
1003*3117ece4Schristos #  error "FSE_FUNCTION_EXTENSION must be defined"
1004*3117ece4Schristos #endif
1005*3117ece4Schristos #ifndef FSE_FUNCTION_TYPE
1006*3117ece4Schristos #  error "FSE_FUNCTION_TYPE must be defined"
1007*3117ece4Schristos #endif
1008*3117ece4Schristos 
1009*3117ece4Schristos /* Function names */
1010*3117ece4Schristos #define FSE_CAT(X,Y) X##Y
1011*3117ece4Schristos #define FSE_FUNCTION_NAME(X,Y) FSE_CAT(X,Y)
1012*3117ece4Schristos #define FSE_TYPE_NAME(X,Y) FSE_CAT(X,Y)
1013*3117ece4Schristos 
1014*3117ece4Schristos static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; }
1015*3117ece4Schristos 
1016*3117ece4Schristos 
1017*3117ece4Schristos static size_t FSE_buildDTable(FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
1018*3117ece4Schristos {
1019*3117ece4Schristos     FSE_DTableHeader DTableH;
1020*3117ece4Schristos     void* const tdPtr = dt+1;   /* because dt is unsigned, 32-bits aligned on 32-bits */
1021*3117ece4Schristos     FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*) (tdPtr);
1022*3117ece4Schristos     const U32 tableSize = 1 << tableLog;
1023*3117ece4Schristos     const U32 tableMask = tableSize-1;
1024*3117ece4Schristos     const U32 step = FSE_tableStep(tableSize);
1025*3117ece4Schristos     U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1];
1026*3117ece4Schristos     U32 position = 0;
1027*3117ece4Schristos     U32 highThreshold = tableSize-1;
1028*3117ece4Schristos     const S16 largeLimit= (S16)(1 << (tableLog-1));
1029*3117ece4Schristos     U32 noLarge = 1;
1030*3117ece4Schristos     U32 s;
1031*3117ece4Schristos 
1032*3117ece4Schristos     /* Sanity Checks */
1033*3117ece4Schristos     if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return ERROR(maxSymbolValue_tooLarge);
1034*3117ece4Schristos     if (tableLog > FSE_MAX_TABLELOG) return ERROR(tableLog_tooLarge);
1035*3117ece4Schristos 
1036*3117ece4Schristos     /* Init, lay down lowprob symbols */
1037*3117ece4Schristos     memset(tableDecode, 0, sizeof(FSE_DECODE_TYPE) * (maxSymbolValue+1) );   /* useless init, but keep static analyzer happy, and we don't need to performance optimize legacy decoders */
1038*3117ece4Schristos     DTableH.tableLog = (U16)tableLog;
1039*3117ece4Schristos     for (s=0; s<=maxSymbolValue; s++)
1040*3117ece4Schristos     {
1041*3117ece4Schristos         if (normalizedCounter[s]==-1)
1042*3117ece4Schristos         {
1043*3117ece4Schristos             tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s;
1044*3117ece4Schristos             symbolNext[s] = 1;
1045*3117ece4Schristos         }
1046*3117ece4Schristos         else
1047*3117ece4Schristos         {
1048*3117ece4Schristos             if (normalizedCounter[s] >= largeLimit) noLarge=0;
1049*3117ece4Schristos             symbolNext[s] = normalizedCounter[s];
1050*3117ece4Schristos         }
1051*3117ece4Schristos     }
1052*3117ece4Schristos 
1053*3117ece4Schristos     /* Spread symbols */
1054*3117ece4Schristos     for (s=0; s<=maxSymbolValue; s++)
1055*3117ece4Schristos     {
1056*3117ece4Schristos         int i;
1057*3117ece4Schristos         for (i=0; i<normalizedCounter[s]; i++)
1058*3117ece4Schristos         {
1059*3117ece4Schristos             tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s;
1060*3117ece4Schristos             position = (position + step) & tableMask;
1061*3117ece4Schristos             while (position > highThreshold) position = (position + step) & tableMask;   /* lowprob area */
1062*3117ece4Schristos         }
1063*3117ece4Schristos     }
1064*3117ece4Schristos 
1065*3117ece4Schristos     if (position!=0) return ERROR(GENERIC);   /* position must reach all cells once, otherwise normalizedCounter is incorrect */
1066*3117ece4Schristos 
1067*3117ece4Schristos     /* Build Decoding table */
1068*3117ece4Schristos     {
1069*3117ece4Schristos         U32 i;
1070*3117ece4Schristos         for (i=0; i<tableSize; i++)
1071*3117ece4Schristos         {
1072*3117ece4Schristos             FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol);
1073*3117ece4Schristos             U16 nextState = symbolNext[symbol]++;
1074*3117ece4Schristos             tableDecode[i].nbBits = (BYTE) (tableLog - BIT_highbit32 ((U32)nextState) );
1075*3117ece4Schristos             tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize);
1076*3117ece4Schristos         }
1077*3117ece4Schristos     }
1078*3117ece4Schristos 
1079*3117ece4Schristos     DTableH.fastMode = (U16)noLarge;
1080*3117ece4Schristos     memcpy(dt, &DTableH, sizeof(DTableH));
1081*3117ece4Schristos     return 0;
1082*3117ece4Schristos }
1083*3117ece4Schristos 
1084*3117ece4Schristos 
1085*3117ece4Schristos #ifndef FSE_COMMONDEFS_ONLY
1086*3117ece4Schristos /******************************************
1087*3117ece4Schristos *  FSE helper functions
1088*3117ece4Schristos ******************************************/
1089*3117ece4Schristos static unsigned FSE_isError(size_t code) { return ERR_isError(code); }
1090*3117ece4Schristos 
1091*3117ece4Schristos 
1092*3117ece4Schristos /****************************************************************
1093*3117ece4Schristos *  FSE NCount encoding-decoding
1094*3117ece4Schristos ****************************************************************/
1095*3117ece4Schristos static short FSE_abs(short a)
1096*3117ece4Schristos {
1097*3117ece4Schristos     return a<0 ? -a : a;
1098*3117ece4Schristos }
1099*3117ece4Schristos 
1100*3117ece4Schristos static size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
1101*3117ece4Schristos                  const void* headerBuffer, size_t hbSize)
1102*3117ece4Schristos {
1103*3117ece4Schristos     const BYTE* const istart = (const BYTE*) headerBuffer;
1104*3117ece4Schristos     const BYTE* const iend = istart + hbSize;
1105*3117ece4Schristos     const BYTE* ip = istart;
1106*3117ece4Schristos     int nbBits;
1107*3117ece4Schristos     int remaining;
1108*3117ece4Schristos     int threshold;
1109*3117ece4Schristos     U32 bitStream;
1110*3117ece4Schristos     int bitCount;
1111*3117ece4Schristos     unsigned charnum = 0;
1112*3117ece4Schristos     int previous0 = 0;
1113*3117ece4Schristos 
1114*3117ece4Schristos     if (hbSize < 4) return ERROR(srcSize_wrong);
1115*3117ece4Schristos     bitStream = MEM_readLE32(ip);
1116*3117ece4Schristos     nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG;   /* extract tableLog */
1117*3117ece4Schristos     if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return ERROR(tableLog_tooLarge);
1118*3117ece4Schristos     bitStream >>= 4;
1119*3117ece4Schristos     bitCount = 4;
1120*3117ece4Schristos     *tableLogPtr = nbBits;
1121*3117ece4Schristos     remaining = (1<<nbBits)+1;
1122*3117ece4Schristos     threshold = 1<<nbBits;
1123*3117ece4Schristos     nbBits++;
1124*3117ece4Schristos 
1125*3117ece4Schristos     while ((remaining>1) && (charnum<=*maxSVPtr))
1126*3117ece4Schristos     {
1127*3117ece4Schristos         if (previous0)
1128*3117ece4Schristos         {
1129*3117ece4Schristos             unsigned n0 = charnum;
1130*3117ece4Schristos             while ((bitStream & 0xFFFF) == 0xFFFF)
1131*3117ece4Schristos             {
1132*3117ece4Schristos                 n0+=24;
1133*3117ece4Schristos                 if (ip < iend-5)
1134*3117ece4Schristos                 {
1135*3117ece4Schristos                     ip+=2;
1136*3117ece4Schristos                     bitStream = MEM_readLE32(ip) >> bitCount;
1137*3117ece4Schristos                 }
1138*3117ece4Schristos                 else
1139*3117ece4Schristos                 {
1140*3117ece4Schristos                     bitStream >>= 16;
1141*3117ece4Schristos                     bitCount+=16;
1142*3117ece4Schristos                 }
1143*3117ece4Schristos             }
1144*3117ece4Schristos             while ((bitStream & 3) == 3)
1145*3117ece4Schristos             {
1146*3117ece4Schristos                 n0+=3;
1147*3117ece4Schristos                 bitStream>>=2;
1148*3117ece4Schristos                 bitCount+=2;
1149*3117ece4Schristos             }
1150*3117ece4Schristos             n0 += bitStream & 3;
1151*3117ece4Schristos             bitCount += 2;
1152*3117ece4Schristos             if (n0 > *maxSVPtr) return ERROR(maxSymbolValue_tooSmall);
1153*3117ece4Schristos             while (charnum < n0) normalizedCounter[charnum++] = 0;
1154*3117ece4Schristos             if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4))
1155*3117ece4Schristos             {
1156*3117ece4Schristos                 ip += bitCount>>3;
1157*3117ece4Schristos                 bitCount &= 7;
1158*3117ece4Schristos                 bitStream = MEM_readLE32(ip) >> bitCount;
1159*3117ece4Schristos             }
1160*3117ece4Schristos             else
1161*3117ece4Schristos                 bitStream >>= 2;
1162*3117ece4Schristos         }
1163*3117ece4Schristos         {
1164*3117ece4Schristos             const short max = (short)((2*threshold-1)-remaining);
1165*3117ece4Schristos             short count;
1166*3117ece4Schristos 
1167*3117ece4Schristos             if ((bitStream & (threshold-1)) < (U32)max)
1168*3117ece4Schristos             {
1169*3117ece4Schristos                 count = (short)(bitStream & (threshold-1));
1170*3117ece4Schristos                 bitCount   += nbBits-1;
1171*3117ece4Schristos             }
1172*3117ece4Schristos             else
1173*3117ece4Schristos             {
1174*3117ece4Schristos                 count = (short)(bitStream & (2*threshold-1));
1175*3117ece4Schristos                 if (count >= threshold) count -= max;
1176*3117ece4Schristos                 bitCount   += nbBits;
1177*3117ece4Schristos             }
1178*3117ece4Schristos 
1179*3117ece4Schristos             count--;   /* extra accuracy */
1180*3117ece4Schristos             remaining -= FSE_abs(count);
1181*3117ece4Schristos             normalizedCounter[charnum++] = count;
1182*3117ece4Schristos             previous0 = !count;
1183*3117ece4Schristos             while (remaining < threshold)
1184*3117ece4Schristos             {
1185*3117ece4Schristos                 nbBits--;
1186*3117ece4Schristos                 threshold >>= 1;
1187*3117ece4Schristos             }
1188*3117ece4Schristos 
1189*3117ece4Schristos             {
1190*3117ece4Schristos                 if ((ip <= iend-7) || (ip + (bitCount>>3) <= iend-4))
1191*3117ece4Schristos                 {
1192*3117ece4Schristos                     ip += bitCount>>3;
1193*3117ece4Schristos                     bitCount &= 7;
1194*3117ece4Schristos                 }
1195*3117ece4Schristos                 else
1196*3117ece4Schristos                 {
1197*3117ece4Schristos                     bitCount -= (int)(8 * (iend - 4 - ip));
1198*3117ece4Schristos                     ip = iend - 4;
1199*3117ece4Schristos                 }
1200*3117ece4Schristos                 bitStream = MEM_readLE32(ip) >> (bitCount & 31);
1201*3117ece4Schristos             }
1202*3117ece4Schristos         }
1203*3117ece4Schristos     }
1204*3117ece4Schristos     if (remaining != 1) return ERROR(GENERIC);
1205*3117ece4Schristos     *maxSVPtr = charnum-1;
1206*3117ece4Schristos 
1207*3117ece4Schristos     ip += (bitCount+7)>>3;
1208*3117ece4Schristos     if ((size_t)(ip-istart) > hbSize) return ERROR(srcSize_wrong);
1209*3117ece4Schristos     return ip-istart;
1210*3117ece4Schristos }
1211*3117ece4Schristos 
1212*3117ece4Schristos 
1213*3117ece4Schristos /*********************************************************
1214*3117ece4Schristos *  Decompression (Byte symbols)
1215*3117ece4Schristos *********************************************************/
1216*3117ece4Schristos static size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue)
1217*3117ece4Schristos {
1218*3117ece4Schristos     void* ptr = dt;
1219*3117ece4Schristos     FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr;
1220*3117ece4Schristos     void* dPtr = dt + 1;
1221*3117ece4Schristos     FSE_decode_t* const cell = (FSE_decode_t*)dPtr;
1222*3117ece4Schristos 
1223*3117ece4Schristos     DTableH->tableLog = 0;
1224*3117ece4Schristos     DTableH->fastMode = 0;
1225*3117ece4Schristos 
1226*3117ece4Schristos     cell->newState = 0;
1227*3117ece4Schristos     cell->symbol = symbolValue;
1228*3117ece4Schristos     cell->nbBits = 0;
1229*3117ece4Schristos 
1230*3117ece4Schristos     return 0;
1231*3117ece4Schristos }
1232*3117ece4Schristos 
1233*3117ece4Schristos 
1234*3117ece4Schristos static size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits)
1235*3117ece4Schristos {
1236*3117ece4Schristos     void* ptr = dt;
1237*3117ece4Schristos     FSE_DTableHeader* const DTableH = (FSE_DTableHeader*)ptr;
1238*3117ece4Schristos     void* dPtr = dt + 1;
1239*3117ece4Schristos     FSE_decode_t* const dinfo = (FSE_decode_t*)dPtr;
1240*3117ece4Schristos     const unsigned tableSize = 1 << nbBits;
1241*3117ece4Schristos     const unsigned tableMask = tableSize - 1;
1242*3117ece4Schristos     const unsigned maxSymbolValue = tableMask;
1243*3117ece4Schristos     unsigned s;
1244*3117ece4Schristos 
1245*3117ece4Schristos     /* Sanity checks */
1246*3117ece4Schristos     if (nbBits < 1) return ERROR(GENERIC);         /* min size */
1247*3117ece4Schristos 
1248*3117ece4Schristos     /* Build Decoding Table */
1249*3117ece4Schristos     DTableH->tableLog = (U16)nbBits;
1250*3117ece4Schristos     DTableH->fastMode = 1;
1251*3117ece4Schristos     for (s=0; s<=maxSymbolValue; s++)
1252*3117ece4Schristos     {
1253*3117ece4Schristos         dinfo[s].newState = 0;
1254*3117ece4Schristos         dinfo[s].symbol = (BYTE)s;
1255*3117ece4Schristos         dinfo[s].nbBits = (BYTE)nbBits;
1256*3117ece4Schristos     }
1257*3117ece4Schristos 
1258*3117ece4Schristos     return 0;
1259*3117ece4Schristos }
1260*3117ece4Schristos 
1261*3117ece4Schristos FORCE_INLINE size_t FSE_decompress_usingDTable_generic(
1262*3117ece4Schristos           void* dst, size_t maxDstSize,
1263*3117ece4Schristos     const void* cSrc, size_t cSrcSize,
1264*3117ece4Schristos     const FSE_DTable* dt, const unsigned fast)
1265*3117ece4Schristos {
1266*3117ece4Schristos     BYTE* const ostart = (BYTE*) dst;
1267*3117ece4Schristos     BYTE* op = ostart;
1268*3117ece4Schristos     BYTE* const omax = op + maxDstSize;
1269*3117ece4Schristos     BYTE* const olimit = omax-3;
1270*3117ece4Schristos 
1271*3117ece4Schristos     BIT_DStream_t bitD;
1272*3117ece4Schristos     FSE_DState_t state1;
1273*3117ece4Schristos     FSE_DState_t state2;
1274*3117ece4Schristos     size_t errorCode;
1275*3117ece4Schristos 
1276*3117ece4Schristos     /* Init */
1277*3117ece4Schristos     errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize);   /* replaced last arg by maxCompressed Size */
1278*3117ece4Schristos     if (FSE_isError(errorCode)) return errorCode;
1279*3117ece4Schristos 
1280*3117ece4Schristos     FSE_initDState(&state1, &bitD, dt);
1281*3117ece4Schristos     FSE_initDState(&state2, &bitD, dt);
1282*3117ece4Schristos 
1283*3117ece4Schristos #define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD)
1284*3117ece4Schristos 
1285*3117ece4Schristos     /* 4 symbols per loop */
1286*3117ece4Schristos     for ( ; (BIT_reloadDStream(&bitD)==BIT_DStream_unfinished) && (op<olimit) ; op+=4)
1287*3117ece4Schristos     {
1288*3117ece4Schristos         op[0] = FSE_GETSYMBOL(&state1);
1289*3117ece4Schristos 
1290*3117ece4Schristos         if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1291*3117ece4Schristos             BIT_reloadDStream(&bitD);
1292*3117ece4Schristos 
1293*3117ece4Schristos         op[1] = FSE_GETSYMBOL(&state2);
1294*3117ece4Schristos 
1295*3117ece4Schristos         if (FSE_MAX_TABLELOG*4+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1296*3117ece4Schristos             { if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) { op+=2; break; } }
1297*3117ece4Schristos 
1298*3117ece4Schristos         op[2] = FSE_GETSYMBOL(&state1);
1299*3117ece4Schristos 
1300*3117ece4Schristos         if (FSE_MAX_TABLELOG*2+7 > sizeof(bitD.bitContainer)*8)    /* This test must be static */
1301*3117ece4Schristos             BIT_reloadDStream(&bitD);
1302*3117ece4Schristos 
1303*3117ece4Schristos         op[3] = FSE_GETSYMBOL(&state2);
1304*3117ece4Schristos     }
1305*3117ece4Schristos 
1306*3117ece4Schristos     /* tail */
1307*3117ece4Schristos     /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */
1308*3117ece4Schristos     while (1)
1309*3117ece4Schristos     {
1310*3117ece4Schristos         if ( (BIT_reloadDStream(&bitD)>BIT_DStream_completed) || (op==omax) || (BIT_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) )
1311*3117ece4Schristos             break;
1312*3117ece4Schristos 
1313*3117ece4Schristos         *op++ = FSE_GETSYMBOL(&state1);
1314*3117ece4Schristos 
1315*3117ece4Schristos         if ( (BIT_reloadDStream(&bitD)>BIT_DStream_completed) || (op==omax) || (BIT_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) )
1316*3117ece4Schristos             break;
1317*3117ece4Schristos 
1318*3117ece4Schristos         *op++ = FSE_GETSYMBOL(&state2);
1319*3117ece4Schristos     }
1320*3117ece4Schristos 
1321*3117ece4Schristos     /* end ? */
1322*3117ece4Schristos     if (BIT_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2))
1323*3117ece4Schristos         return op-ostart;
1324*3117ece4Schristos 
1325*3117ece4Schristos     if (op==omax) return ERROR(dstSize_tooSmall);   /* dst buffer is full, but cSrc unfinished */
1326*3117ece4Schristos 
1327*3117ece4Schristos     return ERROR(corruption_detected);
1328*3117ece4Schristos }
1329*3117ece4Schristos 
1330*3117ece4Schristos 
1331*3117ece4Schristos static size_t FSE_decompress_usingDTable(void* dst, size_t originalSize,
1332*3117ece4Schristos                             const void* cSrc, size_t cSrcSize,
1333*3117ece4Schristos                             const FSE_DTable* dt)
1334*3117ece4Schristos {
1335*3117ece4Schristos     FSE_DTableHeader DTableH;
1336*3117ece4Schristos     U32 fastMode;
1337*3117ece4Schristos 
1338*3117ece4Schristos     memcpy(&DTableH, dt, sizeof(DTableH));
1339*3117ece4Schristos     fastMode = DTableH.fastMode;
1340*3117ece4Schristos 
1341*3117ece4Schristos     /* select fast mode (static) */
1342*3117ece4Schristos     if (fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
1343*3117ece4Schristos     return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
1344*3117ece4Schristos }
1345*3117ece4Schristos 
1346*3117ece4Schristos 
1347*3117ece4Schristos static size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize)
1348*3117ece4Schristos {
1349*3117ece4Schristos     const BYTE* const istart = (const BYTE*)cSrc;
1350*3117ece4Schristos     const BYTE* ip = istart;
1351*3117ece4Schristos     short counting[FSE_MAX_SYMBOL_VALUE+1];
1352*3117ece4Schristos     DTable_max_t dt;   /* Static analyzer seems unable to understand this table will be properly initialized later */
1353*3117ece4Schristos     unsigned tableLog;
1354*3117ece4Schristos     unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
1355*3117ece4Schristos     size_t errorCode;
1356*3117ece4Schristos 
1357*3117ece4Schristos     if (cSrcSize<2) return ERROR(srcSize_wrong);   /* too small input size */
1358*3117ece4Schristos 
1359*3117ece4Schristos     /* normal FSE decoding mode */
1360*3117ece4Schristos     errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
1361*3117ece4Schristos     if (FSE_isError(errorCode)) return errorCode;
1362*3117ece4Schristos     if (errorCode >= cSrcSize) return ERROR(srcSize_wrong);   /* too small input size */
1363*3117ece4Schristos     ip += errorCode;
1364*3117ece4Schristos     cSrcSize -= errorCode;
1365*3117ece4Schristos 
1366*3117ece4Schristos     errorCode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog);
1367*3117ece4Schristos     if (FSE_isError(errorCode)) return errorCode;
1368*3117ece4Schristos 
1369*3117ece4Schristos     /* always return, even if it is an error code */
1370*3117ece4Schristos     return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt);
1371*3117ece4Schristos }
1372*3117ece4Schristos 
1373*3117ece4Schristos 
1374*3117ece4Schristos 
1375*3117ece4Schristos #endif   /* FSE_COMMONDEFS_ONLY */
1376*3117ece4Schristos 
1377*3117ece4Schristos 
1378*3117ece4Schristos /* ******************************************************************
1379*3117ece4Schristos    Huff0 : Huffman coder, part of New Generation Entropy library
1380*3117ece4Schristos    header file
1381*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet.
1382*3117ece4Schristos 
1383*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
1384*3117ece4Schristos 
1385*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
1386*3117ece4Schristos    modification, are permitted provided that the following conditions are
1387*3117ece4Schristos    met:
1388*3117ece4Schristos 
1389*3117ece4Schristos        * Redistributions of source code must retain the above copyright
1390*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
1391*3117ece4Schristos        * Redistributions in binary form must reproduce the above
1392*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
1393*3117ece4Schristos    in the documentation and/or other materials provided with the
1394*3117ece4Schristos    distribution.
1395*3117ece4Schristos 
1396*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1397*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1398*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1399*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1400*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1401*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1402*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1403*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1404*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1405*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1406*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1407*3117ece4Schristos 
1408*3117ece4Schristos    You can contact the author at :
1409*3117ece4Schristos    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
1410*3117ece4Schristos    - Public forum : https://groups.google.com/forum/#!forum/lz4c
1411*3117ece4Schristos ****************************************************************** */
1412*3117ece4Schristos #ifndef HUFF0_H
1413*3117ece4Schristos #define HUFF0_H
1414*3117ece4Schristos 
1415*3117ece4Schristos #if defined (__cplusplus)
1416*3117ece4Schristos extern "C" {
1417*3117ece4Schristos #endif
1418*3117ece4Schristos 
1419*3117ece4Schristos 
1420*3117ece4Schristos /* ****************************************
1421*3117ece4Schristos *  Dependency
1422*3117ece4Schristos ******************************************/
1423*3117ece4Schristos #include <stddef.h>    /* size_t */
1424*3117ece4Schristos 
1425*3117ece4Schristos 
1426*3117ece4Schristos /* ****************************************
1427*3117ece4Schristos *  Huff0 simple functions
1428*3117ece4Schristos ******************************************/
1429*3117ece4Schristos static size_t HUF_decompress(void* dst,  size_t dstSize,
1430*3117ece4Schristos                 const void* cSrc, size_t cSrcSize);
1431*3117ece4Schristos /*!
1432*3117ece4Schristos HUF_decompress():
1433*3117ece4Schristos     Decompress Huff0 data from buffer 'cSrc', of size 'cSrcSize',
1434*3117ece4Schristos     into already allocated destination buffer 'dst', of size 'dstSize'.
1435*3117ece4Schristos     'dstSize' must be the exact size of original (uncompressed) data.
1436*3117ece4Schristos     Note : in contrast with FSE, HUF_decompress can regenerate RLE (cSrcSize==1) and uncompressed (cSrcSize==dstSize) data, because it knows size to regenerate.
1437*3117ece4Schristos     @return : size of regenerated data (== dstSize)
1438*3117ece4Schristos               or an error code, which can be tested using HUF_isError()
1439*3117ece4Schristos */
1440*3117ece4Schristos 
1441*3117ece4Schristos 
1442*3117ece4Schristos /* ****************************************
1443*3117ece4Schristos *  Tool functions
1444*3117ece4Schristos ******************************************/
1445*3117ece4Schristos /* Error Management */
1446*3117ece4Schristos static unsigned    HUF_isError(size_t code);        /* tells if a return value is an error code */
1447*3117ece4Schristos 
1448*3117ece4Schristos 
1449*3117ece4Schristos #if defined (__cplusplus)
1450*3117ece4Schristos }
1451*3117ece4Schristos #endif
1452*3117ece4Schristos 
1453*3117ece4Schristos #endif   /* HUFF0_H */
1454*3117ece4Schristos 
1455*3117ece4Schristos 
1456*3117ece4Schristos /* ******************************************************************
1457*3117ece4Schristos    Huff0 : Huffman coder, part of New Generation Entropy library
1458*3117ece4Schristos    header file for static linking (only)
1459*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet
1460*3117ece4Schristos 
1461*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
1462*3117ece4Schristos 
1463*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
1464*3117ece4Schristos    modification, are permitted provided that the following conditions are
1465*3117ece4Schristos    met:
1466*3117ece4Schristos 
1467*3117ece4Schristos        * Redistributions of source code must retain the above copyright
1468*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
1469*3117ece4Schristos        * Redistributions in binary form must reproduce the above
1470*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
1471*3117ece4Schristos    in the documentation and/or other materials provided with the
1472*3117ece4Schristos    distribution.
1473*3117ece4Schristos 
1474*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1475*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1476*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1477*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1478*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1479*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1480*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1481*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1482*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1483*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1484*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1485*3117ece4Schristos 
1486*3117ece4Schristos    You can contact the author at :
1487*3117ece4Schristos    - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
1488*3117ece4Schristos    - Public forum : https://groups.google.com/forum/#!forum/lz4c
1489*3117ece4Schristos ****************************************************************** */
1490*3117ece4Schristos #ifndef HUFF0_STATIC_H
1491*3117ece4Schristos #define HUFF0_STATIC_H
1492*3117ece4Schristos 
1493*3117ece4Schristos #if defined (__cplusplus)
1494*3117ece4Schristos extern "C" {
1495*3117ece4Schristos #endif
1496*3117ece4Schristos 
1497*3117ece4Schristos 
1498*3117ece4Schristos 
1499*3117ece4Schristos /* ****************************************
1500*3117ece4Schristos *  Static allocation macros
1501*3117ece4Schristos ******************************************/
1502*3117ece4Schristos /* static allocation of Huff0's DTable */
1503*3117ece4Schristos #define HUF_DTABLE_SIZE(maxTableLog)   (1 + (1<<maxTableLog))  /* nb Cells; use unsigned short for X2, unsigned int for X4 */
1504*3117ece4Schristos #define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
1505*3117ece4Schristos         unsigned short DTable[HUF_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
1506*3117ece4Schristos #define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) \
1507*3117ece4Schristos         unsigned int DTable[HUF_DTABLE_SIZE(maxTableLog)] = { maxTableLog }
1508*3117ece4Schristos #define HUF_CREATE_STATIC_DTABLEX6(DTable, maxTableLog) \
1509*3117ece4Schristos         unsigned int DTable[HUF_DTABLE_SIZE(maxTableLog) * 3 / 2] = { maxTableLog }
1510*3117ece4Schristos 
1511*3117ece4Schristos 
1512*3117ece4Schristos /* ****************************************
1513*3117ece4Schristos *  Advanced decompression functions
1514*3117ece4Schristos ******************************************/
1515*3117ece4Schristos static size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* single-symbol decoder */
1516*3117ece4Schristos static size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* double-symbols decoder */
1517*3117ece4Schristos 
1518*3117ece4Schristos 
1519*3117ece4Schristos /* ****************************************
1520*3117ece4Schristos *  Huff0 detailed API
1521*3117ece4Schristos ******************************************/
1522*3117ece4Schristos /*!
1523*3117ece4Schristos HUF_decompress() does the following:
1524*3117ece4Schristos 1. select the decompression algorithm (X2, X4, X6) based on pre-computed heuristics
1525*3117ece4Schristos 2. build Huffman table from save, using HUF_readDTableXn()
1526*3117ece4Schristos 3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable
1527*3117ece4Schristos 
1528*3117ece4Schristos */
1529*3117ece4Schristos static size_t HUF_readDTableX2 (unsigned short* DTable, const void* src, size_t srcSize);
1530*3117ece4Schristos static size_t HUF_readDTableX4 (unsigned* DTable, const void* src, size_t srcSize);
1531*3117ece4Schristos 
1532*3117ece4Schristos static size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned short* DTable);
1533*3117ece4Schristos static size_t HUF_decompress4X4_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const unsigned* DTable);
1534*3117ece4Schristos 
1535*3117ece4Schristos 
1536*3117ece4Schristos #if defined (__cplusplus)
1537*3117ece4Schristos }
1538*3117ece4Schristos #endif
1539*3117ece4Schristos 
1540*3117ece4Schristos #endif /* HUFF0_STATIC_H */
1541*3117ece4Schristos 
1542*3117ece4Schristos 
1543*3117ece4Schristos 
1544*3117ece4Schristos /* ******************************************************************
1545*3117ece4Schristos    Huff0 : Huffman coder, part of New Generation Entropy library
1546*3117ece4Schristos    Copyright (C) 2013-2015, Yann Collet.
1547*3117ece4Schristos 
1548*3117ece4Schristos    BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
1549*3117ece4Schristos 
1550*3117ece4Schristos    Redistribution and use in source and binary forms, with or without
1551*3117ece4Schristos    modification, are permitted provided that the following conditions are
1552*3117ece4Schristos    met:
1553*3117ece4Schristos 
1554*3117ece4Schristos        * Redistributions of source code must retain the above copyright
1555*3117ece4Schristos    notice, this list of conditions and the following disclaimer.
1556*3117ece4Schristos        * Redistributions in binary form must reproduce the above
1557*3117ece4Schristos    copyright notice, this list of conditions and the following disclaimer
1558*3117ece4Schristos    in the documentation and/or other materials provided with the
1559*3117ece4Schristos    distribution.
1560*3117ece4Schristos 
1561*3117ece4Schristos    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1562*3117ece4Schristos    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1563*3117ece4Schristos    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1564*3117ece4Schristos    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1565*3117ece4Schristos    OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1566*3117ece4Schristos    SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1567*3117ece4Schristos    LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1568*3117ece4Schristos    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1569*3117ece4Schristos    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1570*3117ece4Schristos    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1571*3117ece4Schristos    OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1572*3117ece4Schristos 
1573*3117ece4Schristos     You can contact the author at :
1574*3117ece4Schristos     - FSE+Huff0 source repository : https://github.com/Cyan4973/FiniteStateEntropy
1575*3117ece4Schristos ****************************************************************** */
1576*3117ece4Schristos 
1577*3117ece4Schristos /* **************************************************************
1578*3117ece4Schristos *  Compiler specifics
1579*3117ece4Schristos ****************************************************************/
1580*3117ece4Schristos #if defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */)
1581*3117ece4Schristos /* inline is defined */
1582*3117ece4Schristos #elif defined(_MSC_VER)
1583*3117ece4Schristos #  define inline __inline
1584*3117ece4Schristos #else
1585*3117ece4Schristos #  define inline /* disable inline */
1586*3117ece4Schristos #endif
1587*3117ece4Schristos 
1588*3117ece4Schristos 
1589*3117ece4Schristos #ifdef _MSC_VER    /* Visual Studio */
1590*3117ece4Schristos #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
1591*3117ece4Schristos #endif
1592*3117ece4Schristos 
1593*3117ece4Schristos 
1594*3117ece4Schristos /* **************************************************************
1595*3117ece4Schristos *  Includes
1596*3117ece4Schristos ****************************************************************/
1597*3117ece4Schristos #include <stdlib.h>     /* malloc, free, qsort */
1598*3117ece4Schristos #include <string.h>     /* memcpy, memset */
1599*3117ece4Schristos #include <stdio.h>      /* printf (debug) */
1600*3117ece4Schristos 
1601*3117ece4Schristos 
1602*3117ece4Schristos /* **************************************************************
1603*3117ece4Schristos *  Constants
1604*3117ece4Schristos ****************************************************************/
1605*3117ece4Schristos #define HUF_ABSOLUTEMAX_TABLELOG  16   /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
1606*3117ece4Schristos #define HUF_MAX_TABLELOG  12           /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
1607*3117ece4Schristos #define HUF_DEFAULT_TABLELOG  HUF_MAX_TABLELOG   /* tableLog by default, when not specified */
1608*3117ece4Schristos #define HUF_MAX_SYMBOL_VALUE 255
1609*3117ece4Schristos #if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG)
1610*3117ece4Schristos #  error "HUF_MAX_TABLELOG is too large !"
1611*3117ece4Schristos #endif
1612*3117ece4Schristos 
1613*3117ece4Schristos 
1614*3117ece4Schristos /* **************************************************************
1615*3117ece4Schristos *  Error Management
1616*3117ece4Schristos ****************************************************************/
1617*3117ece4Schristos static unsigned HUF_isError(size_t code) { return ERR_isError(code); }
1618*3117ece4Schristos #define HUF_STATIC_ASSERT(c) { enum { HUF_static_assert = 1/(int)(!!(c)) }; }   /* use only *after* variable declarations */
1619*3117ece4Schristos 
1620*3117ece4Schristos 
1621*3117ece4Schristos 
1622*3117ece4Schristos /*-*******************************************************
1623*3117ece4Schristos *  Huff0 : Huffman block decompression
1624*3117ece4Schristos *********************************************************/
1625*3117ece4Schristos typedef struct { BYTE byte; BYTE nbBits; } HUF_DEltX2;   /* single-symbol decoding */
1626*3117ece4Schristos 
1627*3117ece4Schristos typedef struct { U16 sequence; BYTE nbBits; BYTE length; } HUF_DEltX4;  /* double-symbols decoding */
1628*3117ece4Schristos 
1629*3117ece4Schristos typedef struct { BYTE symbol; BYTE weight; } sortedSymbol_t;
1630*3117ece4Schristos 
1631*3117ece4Schristos /*! HUF_readStats
1632*3117ece4Schristos     Read compact Huffman tree, saved by HUF_writeCTable
1633*3117ece4Schristos     @huffWeight : destination buffer
1634*3117ece4Schristos     @return : size read from `src`
1635*3117ece4Schristos */
1636*3117ece4Schristos static size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats,
1637*3117ece4Schristos                             U32* nbSymbolsPtr, U32* tableLogPtr,
1638*3117ece4Schristos                             const void* src, size_t srcSize)
1639*3117ece4Schristos {
1640*3117ece4Schristos     U32 weightTotal;
1641*3117ece4Schristos     U32 tableLog;
1642*3117ece4Schristos     const BYTE* ip = (const BYTE*) src;
1643*3117ece4Schristos     size_t iSize;
1644*3117ece4Schristos     size_t oSize;
1645*3117ece4Schristos     U32 n;
1646*3117ece4Schristos 
1647*3117ece4Schristos     if (!srcSize) return ERROR(srcSize_wrong);
1648*3117ece4Schristos     iSize = ip[0];
1649*3117ece4Schristos     //memset(huffWeight, 0, hwSize);   /* is not necessary, even though some analyzer complain ... */
1650*3117ece4Schristos 
1651*3117ece4Schristos     if (iSize >= 128)  /* special header */
1652*3117ece4Schristos     {
1653*3117ece4Schristos         if (iSize >= (242))   /* RLE */
1654*3117ece4Schristos         {
1655*3117ece4Schristos             static int l[14] = { 1, 2, 3, 4, 7, 8, 15, 16, 31, 32, 63, 64, 127, 128 };
1656*3117ece4Schristos             oSize = l[iSize-242];
1657*3117ece4Schristos             memset(huffWeight, 1, hwSize);
1658*3117ece4Schristos             iSize = 0;
1659*3117ece4Schristos         }
1660*3117ece4Schristos         else   /* Incompressible */
1661*3117ece4Schristos         {
1662*3117ece4Schristos             oSize = iSize - 127;
1663*3117ece4Schristos             iSize = ((oSize+1)/2);
1664*3117ece4Schristos             if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
1665*3117ece4Schristos             if (oSize >= hwSize) return ERROR(corruption_detected);
1666*3117ece4Schristos             ip += 1;
1667*3117ece4Schristos             for (n=0; n<oSize; n+=2)
1668*3117ece4Schristos             {
1669*3117ece4Schristos                 huffWeight[n]   = ip[n/2] >> 4;
1670*3117ece4Schristos                 huffWeight[n+1] = ip[n/2] & 15;
1671*3117ece4Schristos             }
1672*3117ece4Schristos         }
1673*3117ece4Schristos     }
1674*3117ece4Schristos     else  /* header compressed with FSE (normal case) */
1675*3117ece4Schristos     {
1676*3117ece4Schristos         if (iSize+1 > srcSize) return ERROR(srcSize_wrong);
1677*3117ece4Schristos         oSize = FSE_decompress(huffWeight, hwSize-1, ip+1, iSize);   /* max (hwSize-1) values decoded, as last one is implied */
1678*3117ece4Schristos         if (FSE_isError(oSize)) return oSize;
1679*3117ece4Schristos     }
1680*3117ece4Schristos 
1681*3117ece4Schristos     /* collect weight stats */
1682*3117ece4Schristos     memset(rankStats, 0, (HUF_ABSOLUTEMAX_TABLELOG + 1) * sizeof(U32));
1683*3117ece4Schristos     weightTotal = 0;
1684*3117ece4Schristos     for (n=0; n<oSize; n++)
1685*3117ece4Schristos     {
1686*3117ece4Schristos         if (huffWeight[n] >= HUF_ABSOLUTEMAX_TABLELOG) return ERROR(corruption_detected);
1687*3117ece4Schristos         rankStats[huffWeight[n]]++;
1688*3117ece4Schristos         weightTotal += (1 << huffWeight[n]) >> 1;
1689*3117ece4Schristos     }
1690*3117ece4Schristos     if (weightTotal == 0) return ERROR(corruption_detected);
1691*3117ece4Schristos 
1692*3117ece4Schristos     /* get last non-null symbol weight (implied, total must be 2^n) */
1693*3117ece4Schristos     tableLog = BIT_highbit32(weightTotal) + 1;
1694*3117ece4Schristos     if (tableLog > HUF_ABSOLUTEMAX_TABLELOG) return ERROR(corruption_detected);
1695*3117ece4Schristos     {
1696*3117ece4Schristos         U32 total = 1 << tableLog;
1697*3117ece4Schristos         U32 rest = total - weightTotal;
1698*3117ece4Schristos         U32 verif = 1 << BIT_highbit32(rest);
1699*3117ece4Schristos         U32 lastWeight = BIT_highbit32(rest) + 1;
1700*3117ece4Schristos         if (verif != rest) return ERROR(corruption_detected);    /* last value must be a clean power of 2 */
1701*3117ece4Schristos         huffWeight[oSize] = (BYTE)lastWeight;
1702*3117ece4Schristos         rankStats[lastWeight]++;
1703*3117ece4Schristos     }
1704*3117ece4Schristos 
1705*3117ece4Schristos     /* check tree construction validity */
1706*3117ece4Schristos     if ((rankStats[1] < 2) || (rankStats[1] & 1)) return ERROR(corruption_detected);   /* by construction : at least 2 elts of rank 1, must be even */
1707*3117ece4Schristos 
1708*3117ece4Schristos     /* results */
1709*3117ece4Schristos     *nbSymbolsPtr = (U32)(oSize+1);
1710*3117ece4Schristos     *tableLogPtr = tableLog;
1711*3117ece4Schristos     return iSize+1;
1712*3117ece4Schristos }
1713*3117ece4Schristos 
1714*3117ece4Schristos 
1715*3117ece4Schristos /**************************/
1716*3117ece4Schristos /* single-symbol decoding */
1717*3117ece4Schristos /**************************/
1718*3117ece4Schristos 
1719*3117ece4Schristos static size_t HUF_readDTableX2 (U16* DTable, const void* src, size_t srcSize)
1720*3117ece4Schristos {
1721*3117ece4Schristos     BYTE huffWeight[HUF_MAX_SYMBOL_VALUE + 1];
1722*3117ece4Schristos     U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1];   /* large enough for values from 0 to 16 */
1723*3117ece4Schristos     U32 tableLog = 0;
1724*3117ece4Schristos     size_t iSize;
1725*3117ece4Schristos     U32 nbSymbols = 0;
1726*3117ece4Schristos     U32 n;
1727*3117ece4Schristos     U32 nextRankStart;
1728*3117ece4Schristos     void* const dtPtr = DTable + 1;
1729*3117ece4Schristos     HUF_DEltX2* const dt = (HUF_DEltX2*)dtPtr;
1730*3117ece4Schristos 
1731*3117ece4Schristos     HUF_STATIC_ASSERT(sizeof(HUF_DEltX2) == sizeof(U16));   /* if compilation fails here, assertion is false */
1732*3117ece4Schristos     //memset(huffWeight, 0, sizeof(huffWeight));   /* is not necessary, even though some analyzer complain ... */
1733*3117ece4Schristos 
1734*3117ece4Schristos     iSize = HUF_readStats(huffWeight, HUF_MAX_SYMBOL_VALUE + 1, rankVal, &nbSymbols, &tableLog, src, srcSize);
1735*3117ece4Schristos     if (HUF_isError(iSize)) return iSize;
1736*3117ece4Schristos 
1737*3117ece4Schristos     /* check result */
1738*3117ece4Schristos     if (tableLog > DTable[0]) return ERROR(tableLog_tooLarge);   /* DTable is too small */
1739*3117ece4Schristos     DTable[0] = (U16)tableLog;   /* maybe should separate sizeof DTable, as allocated, from used size of DTable, in case of DTable re-use */
1740*3117ece4Schristos 
1741*3117ece4Schristos     /* Prepare ranks */
1742*3117ece4Schristos     nextRankStart = 0;
1743*3117ece4Schristos     for (n=1; n<=tableLog; n++)
1744*3117ece4Schristos     {
1745*3117ece4Schristos         U32 current = nextRankStart;
1746*3117ece4Schristos         nextRankStart += (rankVal[n] << (n-1));
1747*3117ece4Schristos         rankVal[n] = current;
1748*3117ece4Schristos     }
1749*3117ece4Schristos 
1750*3117ece4Schristos     /* fill DTable */
1751*3117ece4Schristos     for (n=0; n<nbSymbols; n++)
1752*3117ece4Schristos     {
1753*3117ece4Schristos         const U32 w = huffWeight[n];
1754*3117ece4Schristos         const U32 length = (1 << w) >> 1;
1755*3117ece4Schristos         U32 i;
1756*3117ece4Schristos         HUF_DEltX2 D;
1757*3117ece4Schristos         D.byte = (BYTE)n; D.nbBits = (BYTE)(tableLog + 1 - w);
1758*3117ece4Schristos         for (i = rankVal[w]; i < rankVal[w] + length; i++)
1759*3117ece4Schristos             dt[i] = D;
1760*3117ece4Schristos         rankVal[w] += length;
1761*3117ece4Schristos     }
1762*3117ece4Schristos 
1763*3117ece4Schristos     return iSize;
1764*3117ece4Schristos }
1765*3117ece4Schristos 
1766*3117ece4Schristos static BYTE HUF_decodeSymbolX2(BIT_DStream_t* Dstream, const HUF_DEltX2* dt, const U32 dtLog)
1767*3117ece4Schristos {
1768*3117ece4Schristos         const size_t val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */
1769*3117ece4Schristos         const BYTE c = dt[val].byte;
1770*3117ece4Schristos         BIT_skipBits(Dstream, dt[val].nbBits);
1771*3117ece4Schristos         return c;
1772*3117ece4Schristos }
1773*3117ece4Schristos 
1774*3117ece4Schristos #define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) \
1775*3117ece4Schristos     *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog)
1776*3117ece4Schristos 
1777*3117ece4Schristos #define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \
1778*3117ece4Schristos     if (MEM_64bits() || (HUF_MAX_TABLELOG<=12)) \
1779*3117ece4Schristos         HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
1780*3117ece4Schristos 
1781*3117ece4Schristos #define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \
1782*3117ece4Schristos     if (MEM_64bits()) \
1783*3117ece4Schristos         HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr)
1784*3117ece4Schristos 
1785*3117ece4Schristos static inline size_t HUF_decodeStreamX2(BYTE* p, BIT_DStream_t* const bitDPtr, BYTE* const pEnd, const HUF_DEltX2* const dt, const U32 dtLog)
1786*3117ece4Schristos {
1787*3117ece4Schristos     BYTE* const pStart = p;
1788*3117ece4Schristos 
1789*3117ece4Schristos     /* up to 4 symbols at a time */
1790*3117ece4Schristos     while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd-4))
1791*3117ece4Schristos     {
1792*3117ece4Schristos         HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
1793*3117ece4Schristos         HUF_DECODE_SYMBOLX2_1(p, bitDPtr);
1794*3117ece4Schristos         HUF_DECODE_SYMBOLX2_2(p, bitDPtr);
1795*3117ece4Schristos         HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
1796*3117ece4Schristos     }
1797*3117ece4Schristos 
1798*3117ece4Schristos     /* closer to the end */
1799*3117ece4Schristos     while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd))
1800*3117ece4Schristos         HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
1801*3117ece4Schristos 
1802*3117ece4Schristos     /* no more data to retrieve from bitstream, hence no need to reload */
1803*3117ece4Schristos     while (p < pEnd)
1804*3117ece4Schristos         HUF_DECODE_SYMBOLX2_0(p, bitDPtr);
1805*3117ece4Schristos 
1806*3117ece4Schristos     return pEnd-pStart;
1807*3117ece4Schristos }
1808*3117ece4Schristos 
1809*3117ece4Schristos 
1810*3117ece4Schristos static size_t HUF_decompress4X2_usingDTable(
1811*3117ece4Schristos           void* dst,  size_t dstSize,
1812*3117ece4Schristos     const void* cSrc, size_t cSrcSize,
1813*3117ece4Schristos     const U16* DTable)
1814*3117ece4Schristos {
1815*3117ece4Schristos     if (cSrcSize < 10) return ERROR(corruption_detected);   /* strict minimum : jump table + 1 byte per stream */
1816*3117ece4Schristos 
1817*3117ece4Schristos     {
1818*3117ece4Schristos         const BYTE* const istart = (const BYTE*) cSrc;
1819*3117ece4Schristos         BYTE* const ostart = (BYTE*) dst;
1820*3117ece4Schristos         BYTE* const oend = ostart + dstSize;
1821*3117ece4Schristos         const void* const dtPtr = DTable;
1822*3117ece4Schristos         const HUF_DEltX2* const dt = ((const HUF_DEltX2*)dtPtr) +1;
1823*3117ece4Schristos         const U32 dtLog = DTable[0];
1824*3117ece4Schristos         size_t errorCode;
1825*3117ece4Schristos 
1826*3117ece4Schristos         /* Init */
1827*3117ece4Schristos         BIT_DStream_t bitD1;
1828*3117ece4Schristos         BIT_DStream_t bitD2;
1829*3117ece4Schristos         BIT_DStream_t bitD3;
1830*3117ece4Schristos         BIT_DStream_t bitD4;
1831*3117ece4Schristos         const size_t length1 = MEM_readLE16(istart);
1832*3117ece4Schristos         const size_t length2 = MEM_readLE16(istart+2);
1833*3117ece4Schristos         const size_t length3 = MEM_readLE16(istart+4);
1834*3117ece4Schristos         size_t length4;
1835*3117ece4Schristos         const BYTE* const istart1 = istart + 6;  /* jumpTable */
1836*3117ece4Schristos         const BYTE* const istart2 = istart1 + length1;
1837*3117ece4Schristos         const BYTE* const istart3 = istart2 + length2;
1838*3117ece4Schristos         const BYTE* const istart4 = istart3 + length3;
1839*3117ece4Schristos         const size_t segmentSize = (dstSize+3) / 4;
1840*3117ece4Schristos         BYTE* const opStart2 = ostart + segmentSize;
1841*3117ece4Schristos         BYTE* const opStart3 = opStart2 + segmentSize;
1842*3117ece4Schristos         BYTE* const opStart4 = opStart3 + segmentSize;
1843*3117ece4Schristos         BYTE* op1 = ostart;
1844*3117ece4Schristos         BYTE* op2 = opStart2;
1845*3117ece4Schristos         BYTE* op3 = opStart3;
1846*3117ece4Schristos         BYTE* op4 = opStart4;
1847*3117ece4Schristos         U32 endSignal;
1848*3117ece4Schristos 
1849*3117ece4Schristos         length4 = cSrcSize - (length1 + length2 + length3 + 6);
1850*3117ece4Schristos         if (length4 > cSrcSize) return ERROR(corruption_detected);   /* overflow */
1851*3117ece4Schristos         errorCode = BIT_initDStream(&bitD1, istart1, length1);
1852*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
1853*3117ece4Schristos         errorCode = BIT_initDStream(&bitD2, istart2, length2);
1854*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
1855*3117ece4Schristos         errorCode = BIT_initDStream(&bitD3, istart3, length3);
1856*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
1857*3117ece4Schristos         errorCode = BIT_initDStream(&bitD4, istart4, length4);
1858*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
1859*3117ece4Schristos 
1860*3117ece4Schristos         /* 16-32 symbols per loop (4-8 symbols per stream) */
1861*3117ece4Schristos         endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
1862*3117ece4Schristos         for ( ; (endSignal==BIT_DStream_unfinished) && (op4<(oend-7)) ; )
1863*3117ece4Schristos         {
1864*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
1865*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
1866*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
1867*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
1868*3117ece4Schristos             HUF_DECODE_SYMBOLX2_1(op1, &bitD1);
1869*3117ece4Schristos             HUF_DECODE_SYMBOLX2_1(op2, &bitD2);
1870*3117ece4Schristos             HUF_DECODE_SYMBOLX2_1(op3, &bitD3);
1871*3117ece4Schristos             HUF_DECODE_SYMBOLX2_1(op4, &bitD4);
1872*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op1, &bitD1);
1873*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op2, &bitD2);
1874*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op3, &bitD3);
1875*3117ece4Schristos             HUF_DECODE_SYMBOLX2_2(op4, &bitD4);
1876*3117ece4Schristos             HUF_DECODE_SYMBOLX2_0(op1, &bitD1);
1877*3117ece4Schristos             HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
1878*3117ece4Schristos             HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
1879*3117ece4Schristos             HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
1880*3117ece4Schristos 
1881*3117ece4Schristos             endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
1882*3117ece4Schristos         }
1883*3117ece4Schristos 
1884*3117ece4Schristos         /* check corruption */
1885*3117ece4Schristos         if (op1 > opStart2) return ERROR(corruption_detected);
1886*3117ece4Schristos         if (op2 > opStart3) return ERROR(corruption_detected);
1887*3117ece4Schristos         if (op3 > opStart4) return ERROR(corruption_detected);
1888*3117ece4Schristos         /* note : op4 supposed already verified within main loop */
1889*3117ece4Schristos 
1890*3117ece4Schristos         /* finish bitStreams one by one */
1891*3117ece4Schristos         HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog);
1892*3117ece4Schristos         HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog);
1893*3117ece4Schristos         HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog);
1894*3117ece4Schristos         HUF_decodeStreamX2(op4, &bitD4, oend,     dt, dtLog);
1895*3117ece4Schristos 
1896*3117ece4Schristos         /* check */
1897*3117ece4Schristos         endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
1898*3117ece4Schristos         if (!endSignal) return ERROR(corruption_detected);
1899*3117ece4Schristos 
1900*3117ece4Schristos         /* decoded size */
1901*3117ece4Schristos         return dstSize;
1902*3117ece4Schristos     }
1903*3117ece4Schristos }
1904*3117ece4Schristos 
1905*3117ece4Schristos 
1906*3117ece4Schristos static size_t HUF_decompress4X2 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
1907*3117ece4Schristos {
1908*3117ece4Schristos     HUF_CREATE_STATIC_DTABLEX2(DTable, HUF_MAX_TABLELOG);
1909*3117ece4Schristos     const BYTE* ip = (const BYTE*) cSrc;
1910*3117ece4Schristos     size_t errorCode;
1911*3117ece4Schristos 
1912*3117ece4Schristos     errorCode = HUF_readDTableX2 (DTable, cSrc, cSrcSize);
1913*3117ece4Schristos     if (HUF_isError(errorCode)) return errorCode;
1914*3117ece4Schristos     if (errorCode >= cSrcSize) return ERROR(srcSize_wrong);
1915*3117ece4Schristos     ip += errorCode;
1916*3117ece4Schristos     cSrcSize -= errorCode;
1917*3117ece4Schristos 
1918*3117ece4Schristos     return HUF_decompress4X2_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
1919*3117ece4Schristos }
1920*3117ece4Schristos 
1921*3117ece4Schristos 
1922*3117ece4Schristos /***************************/
1923*3117ece4Schristos /* double-symbols decoding */
1924*3117ece4Schristos /***************************/
1925*3117ece4Schristos 
1926*3117ece4Schristos static void HUF_fillDTableX4Level2(HUF_DEltX4* DTable, U32 sizeLog, const U32 consumed,
1927*3117ece4Schristos                            const U32* rankValOrigin, const int minWeight,
1928*3117ece4Schristos                            const sortedSymbol_t* sortedSymbols, const U32 sortedListSize,
1929*3117ece4Schristos                            U32 nbBitsBaseline, U16 baseSeq)
1930*3117ece4Schristos {
1931*3117ece4Schristos     HUF_DEltX4 DElt;
1932*3117ece4Schristos     U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1];
1933*3117ece4Schristos     U32 s;
1934*3117ece4Schristos 
1935*3117ece4Schristos     /* get pre-calculated rankVal */
1936*3117ece4Schristos     memcpy(rankVal, rankValOrigin, sizeof(rankVal));
1937*3117ece4Schristos 
1938*3117ece4Schristos     /* fill skipped values */
1939*3117ece4Schristos     if (minWeight>1)
1940*3117ece4Schristos     {
1941*3117ece4Schristos         U32 i, skipSize = rankVal[minWeight];
1942*3117ece4Schristos         MEM_writeLE16(&(DElt.sequence), baseSeq);
1943*3117ece4Schristos         DElt.nbBits   = (BYTE)(consumed);
1944*3117ece4Schristos         DElt.length   = 1;
1945*3117ece4Schristos         for (i = 0; i < skipSize; i++)
1946*3117ece4Schristos             DTable[i] = DElt;
1947*3117ece4Schristos     }
1948*3117ece4Schristos 
1949*3117ece4Schristos     /* fill DTable */
1950*3117ece4Schristos     for (s=0; s<sortedListSize; s++)   /* note : sortedSymbols already skipped */
1951*3117ece4Schristos     {
1952*3117ece4Schristos         const U32 symbol = sortedSymbols[s].symbol;
1953*3117ece4Schristos         const U32 weight = sortedSymbols[s].weight;
1954*3117ece4Schristos         const U32 nbBits = nbBitsBaseline - weight;
1955*3117ece4Schristos         const U32 length = 1 << (sizeLog-nbBits);
1956*3117ece4Schristos         const U32 start = rankVal[weight];
1957*3117ece4Schristos         U32 i = start;
1958*3117ece4Schristos         const U32 end = start + length;
1959*3117ece4Schristos 
1960*3117ece4Schristos         MEM_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8)));
1961*3117ece4Schristos         DElt.nbBits = (BYTE)(nbBits + consumed);
1962*3117ece4Schristos         DElt.length = 2;
1963*3117ece4Schristos         do { DTable[i++] = DElt; } while (i<end);   /* since length >= 1 */
1964*3117ece4Schristos 
1965*3117ece4Schristos         rankVal[weight] += length;
1966*3117ece4Schristos     }
1967*3117ece4Schristos }
1968*3117ece4Schristos 
1969*3117ece4Schristos typedef U32 rankVal_t[HUF_ABSOLUTEMAX_TABLELOG][HUF_ABSOLUTEMAX_TABLELOG + 1];
1970*3117ece4Schristos 
1971*3117ece4Schristos static void HUF_fillDTableX4(HUF_DEltX4* DTable, const U32 targetLog,
1972*3117ece4Schristos                            const sortedSymbol_t* sortedList, const U32 sortedListSize,
1973*3117ece4Schristos                            const U32* rankStart, rankVal_t rankValOrigin, const U32 maxWeight,
1974*3117ece4Schristos                            const U32 nbBitsBaseline)
1975*3117ece4Schristos {
1976*3117ece4Schristos     U32 rankVal[HUF_ABSOLUTEMAX_TABLELOG + 1];
1977*3117ece4Schristos     const int scaleLog = nbBitsBaseline - targetLog;   /* note : targetLog >= srcLog, hence scaleLog <= 1 */
1978*3117ece4Schristos     const U32 minBits  = nbBitsBaseline - maxWeight;
1979*3117ece4Schristos     U32 s;
1980*3117ece4Schristos 
1981*3117ece4Schristos     memcpy(rankVal, rankValOrigin, sizeof(rankVal));
1982*3117ece4Schristos 
1983*3117ece4Schristos     /* fill DTable */
1984*3117ece4Schristos     for (s=0; s<sortedListSize; s++)
1985*3117ece4Schristos     {
1986*3117ece4Schristos         const U16 symbol = sortedList[s].symbol;
1987*3117ece4Schristos         const U32 weight = sortedList[s].weight;
1988*3117ece4Schristos         const U32 nbBits = nbBitsBaseline - weight;
1989*3117ece4Schristos         const U32 start = rankVal[weight];
1990*3117ece4Schristos         const U32 length = 1 << (targetLog-nbBits);
1991*3117ece4Schristos 
1992*3117ece4Schristos         if (targetLog-nbBits >= minBits)   /* enough room for a second symbol */
1993*3117ece4Schristos         {
1994*3117ece4Schristos             U32 sortedRank;
1995*3117ece4Schristos             int minWeight = nbBits + scaleLog;
1996*3117ece4Schristos             if (minWeight < 1) minWeight = 1;
1997*3117ece4Schristos             sortedRank = rankStart[minWeight];
1998*3117ece4Schristos             HUF_fillDTableX4Level2(DTable+start, targetLog-nbBits, nbBits,
1999*3117ece4Schristos                            rankValOrigin[nbBits], minWeight,
2000*3117ece4Schristos                            sortedList+sortedRank, sortedListSize-sortedRank,
2001*3117ece4Schristos                            nbBitsBaseline, symbol);
2002*3117ece4Schristos         }
2003*3117ece4Schristos         else
2004*3117ece4Schristos         {
2005*3117ece4Schristos             U32 i;
2006*3117ece4Schristos             const U32 end = start + length;
2007*3117ece4Schristos             HUF_DEltX4 DElt;
2008*3117ece4Schristos 
2009*3117ece4Schristos             MEM_writeLE16(&(DElt.sequence), symbol);
2010*3117ece4Schristos             DElt.nbBits   = (BYTE)(nbBits);
2011*3117ece4Schristos             DElt.length   = 1;
2012*3117ece4Schristos             for (i = start; i < end; i++)
2013*3117ece4Schristos                 DTable[i] = DElt;
2014*3117ece4Schristos         }
2015*3117ece4Schristos         rankVal[weight] += length;
2016*3117ece4Schristos     }
2017*3117ece4Schristos }
2018*3117ece4Schristos 
2019*3117ece4Schristos static size_t HUF_readDTableX4 (U32* DTable, const void* src, size_t srcSize)
2020*3117ece4Schristos {
2021*3117ece4Schristos     BYTE weightList[HUF_MAX_SYMBOL_VALUE + 1];
2022*3117ece4Schristos     sortedSymbol_t sortedSymbol[HUF_MAX_SYMBOL_VALUE + 1];
2023*3117ece4Schristos     U32 rankStats[HUF_ABSOLUTEMAX_TABLELOG + 1] = { 0 };
2024*3117ece4Schristos     U32 rankStart0[HUF_ABSOLUTEMAX_TABLELOG + 2] = { 0 };
2025*3117ece4Schristos     U32* const rankStart = rankStart0+1;
2026*3117ece4Schristos     rankVal_t rankVal;
2027*3117ece4Schristos     U32 tableLog, maxW, sizeOfSort, nbSymbols;
2028*3117ece4Schristos     const U32 memLog = DTable[0];
2029*3117ece4Schristos     size_t iSize;
2030*3117ece4Schristos     void* dtPtr = DTable;
2031*3117ece4Schristos     HUF_DEltX4* const dt = ((HUF_DEltX4*)dtPtr) + 1;
2032*3117ece4Schristos 
2033*3117ece4Schristos     HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(U32));   /* if compilation fails here, assertion is false */
2034*3117ece4Schristos     if (memLog > HUF_ABSOLUTEMAX_TABLELOG) return ERROR(tableLog_tooLarge);
2035*3117ece4Schristos     //memset(weightList, 0, sizeof(weightList));   /* is not necessary, even though some analyzer complain ... */
2036*3117ece4Schristos 
2037*3117ece4Schristos     iSize = HUF_readStats(weightList, HUF_MAX_SYMBOL_VALUE + 1, rankStats, &nbSymbols, &tableLog, src, srcSize);
2038*3117ece4Schristos     if (HUF_isError(iSize)) return iSize;
2039*3117ece4Schristos 
2040*3117ece4Schristos     /* check result */
2041*3117ece4Schristos     if (tableLog > memLog) return ERROR(tableLog_tooLarge);   /* DTable can't fit code depth */
2042*3117ece4Schristos 
2043*3117ece4Schristos     /* find maxWeight */
2044*3117ece4Schristos     for (maxW = tableLog; rankStats[maxW]==0; maxW--)
2045*3117ece4Schristos         { if (!maxW) return ERROR(GENERIC); }  /* necessarily finds a solution before maxW==0 */
2046*3117ece4Schristos 
2047*3117ece4Schristos     /* Get start index of each weight */
2048*3117ece4Schristos     {
2049*3117ece4Schristos         U32 w, nextRankStart = 0;
2050*3117ece4Schristos         for (w=1; w<=maxW; w++)
2051*3117ece4Schristos         {
2052*3117ece4Schristos             U32 current = nextRankStart;
2053*3117ece4Schristos             nextRankStart += rankStats[w];
2054*3117ece4Schristos             rankStart[w] = current;
2055*3117ece4Schristos         }
2056*3117ece4Schristos         rankStart[0] = nextRankStart;   /* put all 0w symbols at the end of sorted list*/
2057*3117ece4Schristos         sizeOfSort = nextRankStart;
2058*3117ece4Schristos     }
2059*3117ece4Schristos 
2060*3117ece4Schristos     /* sort symbols by weight */
2061*3117ece4Schristos     {
2062*3117ece4Schristos         U32 s;
2063*3117ece4Schristos         for (s=0; s<nbSymbols; s++)
2064*3117ece4Schristos         {
2065*3117ece4Schristos             U32 w = weightList[s];
2066*3117ece4Schristos             U32 r = rankStart[w]++;
2067*3117ece4Schristos             sortedSymbol[r].symbol = (BYTE)s;
2068*3117ece4Schristos             sortedSymbol[r].weight = (BYTE)w;
2069*3117ece4Schristos         }
2070*3117ece4Schristos         rankStart[0] = 0;   /* forget 0w symbols; this is beginning of weight(1) */
2071*3117ece4Schristos     }
2072*3117ece4Schristos 
2073*3117ece4Schristos     /* Build rankVal */
2074*3117ece4Schristos     {
2075*3117ece4Schristos         const U32 minBits = tableLog+1 - maxW;
2076*3117ece4Schristos         U32 nextRankVal = 0;
2077*3117ece4Schristos         U32 w, consumed;
2078*3117ece4Schristos         const int rescale = (memLog-tableLog) - 1;   /* tableLog <= memLog */
2079*3117ece4Schristos         U32* rankVal0 = rankVal[0];
2080*3117ece4Schristos         for (w=1; w<=maxW; w++)
2081*3117ece4Schristos         {
2082*3117ece4Schristos             U32 current = nextRankVal;
2083*3117ece4Schristos             nextRankVal += rankStats[w] << (w+rescale);
2084*3117ece4Schristos             rankVal0[w] = current;
2085*3117ece4Schristos         }
2086*3117ece4Schristos         for (consumed = minBits; consumed <= memLog - minBits; consumed++)
2087*3117ece4Schristos         {
2088*3117ece4Schristos             U32* rankValPtr = rankVal[consumed];
2089*3117ece4Schristos             for (w = 1; w <= maxW; w++)
2090*3117ece4Schristos             {
2091*3117ece4Schristos                 rankValPtr[w] = rankVal0[w] >> consumed;
2092*3117ece4Schristos             }
2093*3117ece4Schristos         }
2094*3117ece4Schristos     }
2095*3117ece4Schristos 
2096*3117ece4Schristos     HUF_fillDTableX4(dt, memLog,
2097*3117ece4Schristos                    sortedSymbol, sizeOfSort,
2098*3117ece4Schristos                    rankStart0, rankVal, maxW,
2099*3117ece4Schristos                    tableLog+1);
2100*3117ece4Schristos 
2101*3117ece4Schristos     return iSize;
2102*3117ece4Schristos }
2103*3117ece4Schristos 
2104*3117ece4Schristos 
2105*3117ece4Schristos static U32 HUF_decodeSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DEltX4* dt, const U32 dtLog)
2106*3117ece4Schristos {
2107*3117ece4Schristos     const size_t val = BIT_lookBitsFast(DStream, dtLog);   /* note : dtLog >= 1 */
2108*3117ece4Schristos     memcpy(op, dt+val, 2);
2109*3117ece4Schristos     BIT_skipBits(DStream, dt[val].nbBits);
2110*3117ece4Schristos     return dt[val].length;
2111*3117ece4Schristos }
2112*3117ece4Schristos 
2113*3117ece4Schristos static U32 HUF_decodeLastSymbolX4(void* op, BIT_DStream_t* DStream, const HUF_DEltX4* dt, const U32 dtLog)
2114*3117ece4Schristos {
2115*3117ece4Schristos     const size_t val = BIT_lookBitsFast(DStream, dtLog);   /* note : dtLog >= 1 */
2116*3117ece4Schristos     memcpy(op, dt+val, 1);
2117*3117ece4Schristos     if (dt[val].length==1) BIT_skipBits(DStream, dt[val].nbBits);
2118*3117ece4Schristos     else
2119*3117ece4Schristos     {
2120*3117ece4Schristos         if (DStream->bitsConsumed < (sizeof(DStream->bitContainer)*8))
2121*3117ece4Schristos         {
2122*3117ece4Schristos             BIT_skipBits(DStream, dt[val].nbBits);
2123*3117ece4Schristos             if (DStream->bitsConsumed > (sizeof(DStream->bitContainer)*8))
2124*3117ece4Schristos                 DStream->bitsConsumed = (sizeof(DStream->bitContainer)*8);   /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */
2125*3117ece4Schristos         }
2126*3117ece4Schristos     }
2127*3117ece4Schristos     return 1;
2128*3117ece4Schristos }
2129*3117ece4Schristos 
2130*3117ece4Schristos 
2131*3117ece4Schristos #define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) \
2132*3117ece4Schristos     ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2133*3117ece4Schristos 
2134*3117ece4Schristos #define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \
2135*3117ece4Schristos     if (MEM_64bits() || (HUF_MAX_TABLELOG<=12)) \
2136*3117ece4Schristos         ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2137*3117ece4Schristos 
2138*3117ece4Schristos #define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \
2139*3117ece4Schristos     if (MEM_64bits()) \
2140*3117ece4Schristos         ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog)
2141*3117ece4Schristos 
2142*3117ece4Schristos static inline size_t HUF_decodeStreamX4(BYTE* p, BIT_DStream_t* bitDPtr, BYTE* const pEnd, const HUF_DEltX4* const dt, const U32 dtLog)
2143*3117ece4Schristos {
2144*3117ece4Schristos     BYTE* const pStart = p;
2145*3117ece4Schristos 
2146*3117ece4Schristos     /* up to 8 symbols at a time */
2147*3117ece4Schristos     while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd-7))
2148*3117ece4Schristos     {
2149*3117ece4Schristos         HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
2150*3117ece4Schristos         HUF_DECODE_SYMBOLX4_1(p, bitDPtr);
2151*3117ece4Schristos         HUF_DECODE_SYMBOLX4_2(p, bitDPtr);
2152*3117ece4Schristos         HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
2153*3117ece4Schristos     }
2154*3117ece4Schristos 
2155*3117ece4Schristos     /* closer to the end */
2156*3117ece4Schristos     while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd-2))
2157*3117ece4Schristos         HUF_DECODE_SYMBOLX4_0(p, bitDPtr);
2158*3117ece4Schristos 
2159*3117ece4Schristos     while (p <= pEnd-2)
2160*3117ece4Schristos         HUF_DECODE_SYMBOLX4_0(p, bitDPtr);   /* no need to reload : reached the end of DStream */
2161*3117ece4Schristos 
2162*3117ece4Schristos     if (p < pEnd)
2163*3117ece4Schristos         p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog);
2164*3117ece4Schristos 
2165*3117ece4Schristos     return p-pStart;
2166*3117ece4Schristos }
2167*3117ece4Schristos 
2168*3117ece4Schristos static size_t HUF_decompress4X4_usingDTable(
2169*3117ece4Schristos           void* dst,  size_t dstSize,
2170*3117ece4Schristos     const void* cSrc, size_t cSrcSize,
2171*3117ece4Schristos     const U32* DTable)
2172*3117ece4Schristos {
2173*3117ece4Schristos     if (cSrcSize < 10) return ERROR(corruption_detected);   /* strict minimum : jump table + 1 byte per stream */
2174*3117ece4Schristos 
2175*3117ece4Schristos     {
2176*3117ece4Schristos         const BYTE* const istart = (const BYTE*) cSrc;
2177*3117ece4Schristos         BYTE* const ostart = (BYTE*) dst;
2178*3117ece4Schristos         BYTE* const oend = ostart + dstSize;
2179*3117ece4Schristos         const void* const dtPtr = DTable;
2180*3117ece4Schristos         const HUF_DEltX4* const dt = ((const HUF_DEltX4*)dtPtr) +1;
2181*3117ece4Schristos         const U32 dtLog = DTable[0];
2182*3117ece4Schristos         size_t errorCode;
2183*3117ece4Schristos 
2184*3117ece4Schristos         /* Init */
2185*3117ece4Schristos         BIT_DStream_t bitD1;
2186*3117ece4Schristos         BIT_DStream_t bitD2;
2187*3117ece4Schristos         BIT_DStream_t bitD3;
2188*3117ece4Schristos         BIT_DStream_t bitD4;
2189*3117ece4Schristos         const size_t length1 = MEM_readLE16(istart);
2190*3117ece4Schristos         const size_t length2 = MEM_readLE16(istart+2);
2191*3117ece4Schristos         const size_t length3 = MEM_readLE16(istart+4);
2192*3117ece4Schristos         size_t length4;
2193*3117ece4Schristos         const BYTE* const istart1 = istart + 6;  /* jumpTable */
2194*3117ece4Schristos         const BYTE* const istart2 = istart1 + length1;
2195*3117ece4Schristos         const BYTE* const istart3 = istart2 + length2;
2196*3117ece4Schristos         const BYTE* const istart4 = istart3 + length3;
2197*3117ece4Schristos         const size_t segmentSize = (dstSize+3) / 4;
2198*3117ece4Schristos         BYTE* const opStart2 = ostart + segmentSize;
2199*3117ece4Schristos         BYTE* const opStart3 = opStart2 + segmentSize;
2200*3117ece4Schristos         BYTE* const opStart4 = opStart3 + segmentSize;
2201*3117ece4Schristos         BYTE* op1 = ostart;
2202*3117ece4Schristos         BYTE* op2 = opStart2;
2203*3117ece4Schristos         BYTE* op3 = opStart3;
2204*3117ece4Schristos         BYTE* op4 = opStart4;
2205*3117ece4Schristos         U32 endSignal;
2206*3117ece4Schristos 
2207*3117ece4Schristos         length4 = cSrcSize - (length1 + length2 + length3 + 6);
2208*3117ece4Schristos         if (length4 > cSrcSize) return ERROR(corruption_detected);   /* overflow */
2209*3117ece4Schristos         errorCode = BIT_initDStream(&bitD1, istart1, length1);
2210*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
2211*3117ece4Schristos         errorCode = BIT_initDStream(&bitD2, istart2, length2);
2212*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
2213*3117ece4Schristos         errorCode = BIT_initDStream(&bitD3, istart3, length3);
2214*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
2215*3117ece4Schristos         errorCode = BIT_initDStream(&bitD4, istart4, length4);
2216*3117ece4Schristos         if (HUF_isError(errorCode)) return errorCode;
2217*3117ece4Schristos 
2218*3117ece4Schristos         /* 16-32 symbols per loop (4-8 symbols per stream) */
2219*3117ece4Schristos         endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
2220*3117ece4Schristos         for ( ; (endSignal==BIT_DStream_unfinished) && (op4<(oend-7)) ; )
2221*3117ece4Schristos         {
2222*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
2223*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
2224*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
2225*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
2226*3117ece4Schristos             HUF_DECODE_SYMBOLX4_1(op1, &bitD1);
2227*3117ece4Schristos             HUF_DECODE_SYMBOLX4_1(op2, &bitD2);
2228*3117ece4Schristos             HUF_DECODE_SYMBOLX4_1(op3, &bitD3);
2229*3117ece4Schristos             HUF_DECODE_SYMBOLX4_1(op4, &bitD4);
2230*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op1, &bitD1);
2231*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op2, &bitD2);
2232*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op3, &bitD3);
2233*3117ece4Schristos             HUF_DECODE_SYMBOLX4_2(op4, &bitD4);
2234*3117ece4Schristos             HUF_DECODE_SYMBOLX4_0(op1, &bitD1);
2235*3117ece4Schristos             HUF_DECODE_SYMBOLX4_0(op2, &bitD2);
2236*3117ece4Schristos             HUF_DECODE_SYMBOLX4_0(op3, &bitD3);
2237*3117ece4Schristos             HUF_DECODE_SYMBOLX4_0(op4, &bitD4);
2238*3117ece4Schristos 
2239*3117ece4Schristos             endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4);
2240*3117ece4Schristos         }
2241*3117ece4Schristos 
2242*3117ece4Schristos         /* check corruption */
2243*3117ece4Schristos         if (op1 > opStart2) return ERROR(corruption_detected);
2244*3117ece4Schristos         if (op2 > opStart3) return ERROR(corruption_detected);
2245*3117ece4Schristos         if (op3 > opStart4) return ERROR(corruption_detected);
2246*3117ece4Schristos         /* note : op4 supposed already verified within main loop */
2247*3117ece4Schristos 
2248*3117ece4Schristos         /* finish bitStreams one by one */
2249*3117ece4Schristos         HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog);
2250*3117ece4Schristos         HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog);
2251*3117ece4Schristos         HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog);
2252*3117ece4Schristos         HUF_decodeStreamX4(op4, &bitD4, oend,     dt, dtLog);
2253*3117ece4Schristos 
2254*3117ece4Schristos         /* check */
2255*3117ece4Schristos         endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4);
2256*3117ece4Schristos         if (!endSignal) return ERROR(corruption_detected);
2257*3117ece4Schristos 
2258*3117ece4Schristos         /* decoded size */
2259*3117ece4Schristos         return dstSize;
2260*3117ece4Schristos     }
2261*3117ece4Schristos }
2262*3117ece4Schristos 
2263*3117ece4Schristos 
2264*3117ece4Schristos static size_t HUF_decompress4X4 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2265*3117ece4Schristos {
2266*3117ece4Schristos     HUF_CREATE_STATIC_DTABLEX4(DTable, HUF_MAX_TABLELOG);
2267*3117ece4Schristos     const BYTE* ip = (const BYTE*) cSrc;
2268*3117ece4Schristos 
2269*3117ece4Schristos     size_t hSize = HUF_readDTableX4 (DTable, cSrc, cSrcSize);
2270*3117ece4Schristos     if (HUF_isError(hSize)) return hSize;
2271*3117ece4Schristos     if (hSize >= cSrcSize) return ERROR(srcSize_wrong);
2272*3117ece4Schristos     ip += hSize;
2273*3117ece4Schristos     cSrcSize -= hSize;
2274*3117ece4Schristos 
2275*3117ece4Schristos     return HUF_decompress4X4_usingDTable (dst, dstSize, ip, cSrcSize, DTable);
2276*3117ece4Schristos }
2277*3117ece4Schristos 
2278*3117ece4Schristos 
2279*3117ece4Schristos /**********************************/
2280*3117ece4Schristos /* Generic decompression selector */
2281*3117ece4Schristos /**********************************/
2282*3117ece4Schristos 
2283*3117ece4Schristos typedef struct { U32 tableTime; U32 decode256Time; } algo_time_t;
2284*3117ece4Schristos static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] =
2285*3117ece4Schristos {
2286*3117ece4Schristos     /* single, double, quad */
2287*3117ece4Schristos     {{0,0}, {1,1}, {2,2}},  /* Q==0 : impossible */
2288*3117ece4Schristos     {{0,0}, {1,1}, {2,2}},  /* Q==1 : impossible */
2289*3117ece4Schristos     {{  38,130}, {1313, 74}, {2151, 38}},   /* Q == 2 : 12-18% */
2290*3117ece4Schristos     {{ 448,128}, {1353, 74}, {2238, 41}},   /* Q == 3 : 18-25% */
2291*3117ece4Schristos     {{ 556,128}, {1353, 74}, {2238, 47}},   /* Q == 4 : 25-32% */
2292*3117ece4Schristos     {{ 714,128}, {1418, 74}, {2436, 53}},   /* Q == 5 : 32-38% */
2293*3117ece4Schristos     {{ 883,128}, {1437, 74}, {2464, 61}},   /* Q == 6 : 38-44% */
2294*3117ece4Schristos     {{ 897,128}, {1515, 75}, {2622, 68}},   /* Q == 7 : 44-50% */
2295*3117ece4Schristos     {{ 926,128}, {1613, 75}, {2730, 75}},   /* Q == 8 : 50-56% */
2296*3117ece4Schristos     {{ 947,128}, {1729, 77}, {3359, 77}},   /* Q == 9 : 56-62% */
2297*3117ece4Schristos     {{1107,128}, {2083, 81}, {4006, 84}},   /* Q ==10 : 62-69% */
2298*3117ece4Schristos     {{1177,128}, {2379, 87}, {4785, 88}},   /* Q ==11 : 69-75% */
2299*3117ece4Schristos     {{1242,128}, {2415, 93}, {5155, 84}},   /* Q ==12 : 75-81% */
2300*3117ece4Schristos     {{1349,128}, {2644,106}, {5260,106}},   /* Q ==13 : 81-87% */
2301*3117ece4Schristos     {{1455,128}, {2422,124}, {4174,124}},   /* Q ==14 : 87-93% */
2302*3117ece4Schristos     {{ 722,128}, {1891,145}, {1936,146}},   /* Q ==15 : 93-99% */
2303*3117ece4Schristos };
2304*3117ece4Schristos 
2305*3117ece4Schristos typedef size_t (*decompressionAlgo)(void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);
2306*3117ece4Schristos 
2307*3117ece4Schristos static size_t HUF_decompress (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize)
2308*3117ece4Schristos {
2309*3117ece4Schristos     static const decompressionAlgo decompress[3] = { HUF_decompress4X2, HUF_decompress4X4, NULL };
2310*3117ece4Schristos     /* estimate decompression time */
2311*3117ece4Schristos     U32 Q;
2312*3117ece4Schristos     const U32 D256 = (U32)(dstSize >> 8);
2313*3117ece4Schristos     U32 Dtime[3];
2314*3117ece4Schristos     U32 algoNb = 0;
2315*3117ece4Schristos     int n;
2316*3117ece4Schristos 
2317*3117ece4Schristos     /* validation checks */
2318*3117ece4Schristos     if (dstSize == 0) return ERROR(dstSize_tooSmall);
2319*3117ece4Schristos     if (cSrcSize > dstSize) return ERROR(corruption_detected);   /* invalid */
2320*3117ece4Schristos     if (cSrcSize == dstSize) { memcpy(dst, cSrc, dstSize); return dstSize; }   /* not compressed */
2321*3117ece4Schristos     if (cSrcSize == 1) { memset(dst, *(const BYTE*)cSrc, dstSize); return dstSize; }   /* RLE */
2322*3117ece4Schristos 
2323*3117ece4Schristos     /* decoder timing evaluation */
2324*3117ece4Schristos     Q = (U32)(cSrcSize * 16 / dstSize);   /* Q < 16 since dstSize > cSrcSize */
2325*3117ece4Schristos     for (n=0; n<3; n++)
2326*3117ece4Schristos         Dtime[n] = algoTime[Q][n].tableTime + (algoTime[Q][n].decode256Time * D256);
2327*3117ece4Schristos 
2328*3117ece4Schristos     Dtime[1] += Dtime[1] >> 4; Dtime[2] += Dtime[2] >> 3; /* advantage to algorithms using less memory, for cache eviction */
2329*3117ece4Schristos 
2330*3117ece4Schristos     if (Dtime[1] < Dtime[0]) algoNb = 1;
2331*3117ece4Schristos 
2332*3117ece4Schristos     return decompress[algoNb](dst, dstSize, cSrc, cSrcSize);
2333*3117ece4Schristos 
2334*3117ece4Schristos     //return HUF_decompress4X2(dst, dstSize, cSrc, cSrcSize);   /* multi-streams single-symbol decoding */
2335*3117ece4Schristos     //return HUF_decompress4X4(dst, dstSize, cSrc, cSrcSize);   /* multi-streams double-symbols decoding */
2336*3117ece4Schristos     //return HUF_decompress4X6(dst, dstSize, cSrc, cSrcSize);   /* multi-streams quad-symbols decoding */
2337*3117ece4Schristos }
2338*3117ece4Schristos 
2339*3117ece4Schristos 
2340*3117ece4Schristos 
2341*3117ece4Schristos #endif   /* ZSTD_CCOMMON_H_MODULE */
2342*3117ece4Schristos 
2343*3117ece4Schristos 
2344*3117ece4Schristos /*
2345*3117ece4Schristos     zstd - decompression module fo v0.4 legacy format
2346*3117ece4Schristos     Copyright (C) 2015-2016, Yann Collet.
2347*3117ece4Schristos 
2348*3117ece4Schristos     BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
2349*3117ece4Schristos 
2350*3117ece4Schristos     Redistribution and use in source and binary forms, with or without
2351*3117ece4Schristos     modification, are permitted provided that the following conditions are
2352*3117ece4Schristos     met:
2353*3117ece4Schristos     * Redistributions of source code must retain the above copyright
2354*3117ece4Schristos     notice, this list of conditions and the following disclaimer.
2355*3117ece4Schristos     * Redistributions in binary form must reproduce the above
2356*3117ece4Schristos     copyright notice, this list of conditions and the following disclaimer
2357*3117ece4Schristos     in the documentation and/or other materials provided with the
2358*3117ece4Schristos     distribution.
2359*3117ece4Schristos     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
2360*3117ece4Schristos     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
2361*3117ece4Schristos     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
2362*3117ece4Schristos     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
2363*3117ece4Schristos     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
2364*3117ece4Schristos     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
2365*3117ece4Schristos     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2366*3117ece4Schristos     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2367*3117ece4Schristos     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2368*3117ece4Schristos     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
2369*3117ece4Schristos     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2370*3117ece4Schristos 
2371*3117ece4Schristos     You can contact the author at :
2372*3117ece4Schristos     - zstd source repository : https://github.com/Cyan4973/zstd
2373*3117ece4Schristos     - ztsd public forum : https://groups.google.com/forum/#!forum/lz4c
2374*3117ece4Schristos */
2375*3117ece4Schristos 
2376*3117ece4Schristos /* ***************************************************************
2377*3117ece4Schristos *  Tuning parameters
2378*3117ece4Schristos *****************************************************************/
2379*3117ece4Schristos /*!
2380*3117ece4Schristos  * HEAPMODE :
2381*3117ece4Schristos  * Select how default decompression function ZSTD_decompress() will allocate memory,
2382*3117ece4Schristos  * in memory stack (0), or in memory heap (1, requires malloc())
2383*3117ece4Schristos  */
2384*3117ece4Schristos #ifndef ZSTD_HEAPMODE
2385*3117ece4Schristos #  define ZSTD_HEAPMODE 1
2386*3117ece4Schristos #endif
2387*3117ece4Schristos 
2388*3117ece4Schristos 
2389*3117ece4Schristos /* *******************************************************
2390*3117ece4Schristos *  Includes
2391*3117ece4Schristos *********************************************************/
2392*3117ece4Schristos #include <stdlib.h>      /* calloc */
2393*3117ece4Schristos #include <string.h>      /* memcpy, memmove */
2394*3117ece4Schristos #include <stdio.h>       /* debug : printf */
2395*3117ece4Schristos 
2396*3117ece4Schristos 
2397*3117ece4Schristos /* *******************************************************
2398*3117ece4Schristos *  Compiler specifics
2399*3117ece4Schristos *********************************************************/
2400*3117ece4Schristos #ifdef _MSC_VER    /* Visual Studio */
2401*3117ece4Schristos #  include <intrin.h>                    /* For Visual 2005 */
2402*3117ece4Schristos #  pragma warning(disable : 4127)        /* disable: C4127: conditional expression is constant */
2403*3117ece4Schristos #  pragma warning(disable : 4324)        /* disable: C4324: padded structure */
2404*3117ece4Schristos #endif
2405*3117ece4Schristos 
2406*3117ece4Schristos 
2407*3117ece4Schristos /* *************************************
2408*3117ece4Schristos *  Local types
2409*3117ece4Schristos ***************************************/
2410*3117ece4Schristos typedef struct
2411*3117ece4Schristos {
2412*3117ece4Schristos     blockType_t blockType;
2413*3117ece4Schristos     U32 origSize;
2414*3117ece4Schristos } blockProperties_t;
2415*3117ece4Schristos 
2416*3117ece4Schristos 
2417*3117ece4Schristos /* *******************************************************
2418*3117ece4Schristos *  Memory operations
2419*3117ece4Schristos **********************************************************/
2420*3117ece4Schristos static void ZSTD_copy4(void* dst, const void* src) { memcpy(dst, src, 4); }
2421*3117ece4Schristos 
2422*3117ece4Schristos 
2423*3117ece4Schristos /* *************************************
2424*3117ece4Schristos *  Error Management
2425*3117ece4Schristos ***************************************/
2426*3117ece4Schristos 
2427*3117ece4Schristos /*! ZSTD_isError
2428*3117ece4Schristos *   tells if a return value is an error code */
2429*3117ece4Schristos static unsigned ZSTD_isError(size_t code) { return ERR_isError(code); }
2430*3117ece4Schristos 
2431*3117ece4Schristos 
2432*3117ece4Schristos /* *************************************************************
2433*3117ece4Schristos *   Context management
2434*3117ece4Schristos ***************************************************************/
2435*3117ece4Schristos typedef enum { ZSTDds_getFrameHeaderSize, ZSTDds_decodeFrameHeader,
2436*3117ece4Schristos                ZSTDds_decodeBlockHeader, ZSTDds_decompressBlock } ZSTD_dStage;
2437*3117ece4Schristos 
2438*3117ece4Schristos struct ZSTDv04_Dctx_s
2439*3117ece4Schristos {
2440*3117ece4Schristos     U32 LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)];
2441*3117ece4Schristos     U32 OffTable[FSE_DTABLE_SIZE_U32(OffFSELog)];
2442*3117ece4Schristos     U32 MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)];
2443*3117ece4Schristos     const void* previousDstEnd;
2444*3117ece4Schristos     const void* base;
2445*3117ece4Schristos     const void* vBase;
2446*3117ece4Schristos     const void* dictEnd;
2447*3117ece4Schristos     size_t expected;
2448*3117ece4Schristos     size_t headerSize;
2449*3117ece4Schristos     ZSTD_parameters params;
2450*3117ece4Schristos     blockType_t bType;
2451*3117ece4Schristos     ZSTD_dStage stage;
2452*3117ece4Schristos     const BYTE* litPtr;
2453*3117ece4Schristos     size_t litSize;
2454*3117ece4Schristos     BYTE litBuffer[BLOCKSIZE + 8 /* margin for wildcopy */];
2455*3117ece4Schristos     BYTE headerBuffer[ZSTD_frameHeaderSize_max];
2456*3117ece4Schristos };  /* typedef'd to ZSTD_DCtx within "zstd_static.h" */
2457*3117ece4Schristos 
2458*3117ece4Schristos static size_t ZSTD_resetDCtx(ZSTD_DCtx* dctx)
2459*3117ece4Schristos {
2460*3117ece4Schristos     dctx->expected = ZSTD_frameHeaderSize_min;
2461*3117ece4Schristos     dctx->stage = ZSTDds_getFrameHeaderSize;
2462*3117ece4Schristos     dctx->previousDstEnd = NULL;
2463*3117ece4Schristos     dctx->base = NULL;
2464*3117ece4Schristos     dctx->vBase = NULL;
2465*3117ece4Schristos     dctx->dictEnd = NULL;
2466*3117ece4Schristos     return 0;
2467*3117ece4Schristos }
2468*3117ece4Schristos 
2469*3117ece4Schristos static ZSTD_DCtx* ZSTD_createDCtx(void)
2470*3117ece4Schristos {
2471*3117ece4Schristos     ZSTD_DCtx* dctx = (ZSTD_DCtx*)malloc(sizeof(ZSTD_DCtx));
2472*3117ece4Schristos     if (dctx==NULL) return NULL;
2473*3117ece4Schristos     ZSTD_resetDCtx(dctx);
2474*3117ece4Schristos     return dctx;
2475*3117ece4Schristos }
2476*3117ece4Schristos 
2477*3117ece4Schristos static size_t ZSTD_freeDCtx(ZSTD_DCtx* dctx)
2478*3117ece4Schristos {
2479*3117ece4Schristos     free(dctx);
2480*3117ece4Schristos     return 0;
2481*3117ece4Schristos }
2482*3117ece4Schristos 
2483*3117ece4Schristos 
2484*3117ece4Schristos /* *************************************************************
2485*3117ece4Schristos *   Decompression section
2486*3117ece4Schristos ***************************************************************/
2487*3117ece4Schristos /** ZSTD_decodeFrameHeader_Part1
2488*3117ece4Schristos *   decode the 1st part of the Frame Header, which tells Frame Header size.
2489*3117ece4Schristos *   srcSize must be == ZSTD_frameHeaderSize_min
2490*3117ece4Schristos *   @return : the full size of the Frame Header */
2491*3117ece4Schristos static size_t ZSTD_decodeFrameHeader_Part1(ZSTD_DCtx* zc, const void* src, size_t srcSize)
2492*3117ece4Schristos {
2493*3117ece4Schristos     U32 magicNumber;
2494*3117ece4Schristos     if (srcSize != ZSTD_frameHeaderSize_min) return ERROR(srcSize_wrong);
2495*3117ece4Schristos     magicNumber = MEM_readLE32(src);
2496*3117ece4Schristos     if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown);
2497*3117ece4Schristos     zc->headerSize = ZSTD_frameHeaderSize_min;
2498*3117ece4Schristos     return zc->headerSize;
2499*3117ece4Schristos }
2500*3117ece4Schristos 
2501*3117ece4Schristos 
2502*3117ece4Schristos static size_t ZSTD_getFrameParams(ZSTD_parameters* params, const void* src, size_t srcSize)
2503*3117ece4Schristos {
2504*3117ece4Schristos     U32 magicNumber;
2505*3117ece4Schristos     if (srcSize < ZSTD_frameHeaderSize_min) return ZSTD_frameHeaderSize_max;
2506*3117ece4Schristos     magicNumber = MEM_readLE32(src);
2507*3117ece4Schristos     if (magicNumber != ZSTD_MAGICNUMBER) return ERROR(prefix_unknown);
2508*3117ece4Schristos     memset(params, 0, sizeof(*params));
2509*3117ece4Schristos     params->windowLog = (((const BYTE*)src)[4] & 15) + ZSTD_WINDOWLOG_ABSOLUTEMIN;
2510*3117ece4Schristos     if ((((const BYTE*)src)[4] >> 4) != 0) return ERROR(frameParameter_unsupported);   /* reserved bits */
2511*3117ece4Schristos     return 0;
2512*3117ece4Schristos }
2513*3117ece4Schristos 
2514*3117ece4Schristos /** ZSTD_decodeFrameHeader_Part2
2515*3117ece4Schristos *   decode the full Frame Header
2516*3117ece4Schristos *   srcSize must be the size provided by ZSTD_decodeFrameHeader_Part1
2517*3117ece4Schristos *   @return : 0, or an error code, which can be tested using ZSTD_isError() */
2518*3117ece4Schristos static size_t ZSTD_decodeFrameHeader_Part2(ZSTD_DCtx* zc, const void* src, size_t srcSize)
2519*3117ece4Schristos {
2520*3117ece4Schristos     size_t result;
2521*3117ece4Schristos     if (srcSize != zc->headerSize) return ERROR(srcSize_wrong);
2522*3117ece4Schristos     result = ZSTD_getFrameParams(&(zc->params), src, srcSize);
2523*3117ece4Schristos     if ((MEM_32bits()) && (zc->params.windowLog > 25)) return ERROR(frameParameter_unsupported);
2524*3117ece4Schristos     return result;
2525*3117ece4Schristos }
2526*3117ece4Schristos 
2527*3117ece4Schristos 
2528*3117ece4Schristos static size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr)
2529*3117ece4Schristos {
2530*3117ece4Schristos     const BYTE* const in = (const BYTE* const)src;
2531*3117ece4Schristos     BYTE headerFlags;
2532*3117ece4Schristos     U32 cSize;
2533*3117ece4Schristos 
2534*3117ece4Schristos     if (srcSize < 3) return ERROR(srcSize_wrong);
2535*3117ece4Schristos 
2536*3117ece4Schristos     headerFlags = *in;
2537*3117ece4Schristos     cSize = in[2] + (in[1]<<8) + ((in[0] & 7)<<16);
2538*3117ece4Schristos 
2539*3117ece4Schristos     bpPtr->blockType = (blockType_t)(headerFlags >> 6);
2540*3117ece4Schristos     bpPtr->origSize = (bpPtr->blockType == bt_rle) ? cSize : 0;
2541*3117ece4Schristos 
2542*3117ece4Schristos     if (bpPtr->blockType == bt_end) return 0;
2543*3117ece4Schristos     if (bpPtr->blockType == bt_rle) return 1;
2544*3117ece4Schristos     return cSize;
2545*3117ece4Schristos }
2546*3117ece4Schristos 
2547*3117ece4Schristos static size_t ZSTD_copyRawBlock(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
2548*3117ece4Schristos {
2549*3117ece4Schristos     if (srcSize > maxDstSize) return ERROR(dstSize_tooSmall);
2550*3117ece4Schristos     if (srcSize > 0) {
2551*3117ece4Schristos         memcpy(dst, src, srcSize);
2552*3117ece4Schristos     }
2553*3117ece4Schristos     return srcSize;
2554*3117ece4Schristos }
2555*3117ece4Schristos 
2556*3117ece4Schristos 
2557*3117ece4Schristos /** ZSTD_decompressLiterals
2558*3117ece4Schristos     @return : nb of bytes read from src, or an error code*/
2559*3117ece4Schristos static size_t ZSTD_decompressLiterals(void* dst, size_t* maxDstSizePtr,
2560*3117ece4Schristos                                 const void* src, size_t srcSize)
2561*3117ece4Schristos {
2562*3117ece4Schristos     const BYTE* ip = (const BYTE*)src;
2563*3117ece4Schristos 
2564*3117ece4Schristos     const size_t litSize = (MEM_readLE32(src) & 0x1FFFFF) >> 2;   /* no buffer issue : srcSize >= MIN_CBLOCK_SIZE */
2565*3117ece4Schristos     const size_t litCSize = (MEM_readLE32(ip+2) & 0xFFFFFF) >> 5;   /* no buffer issue : srcSize >= MIN_CBLOCK_SIZE */
2566*3117ece4Schristos 
2567*3117ece4Schristos     if (litSize > *maxDstSizePtr) return ERROR(corruption_detected);
2568*3117ece4Schristos     if (litCSize + 5 > srcSize) return ERROR(corruption_detected);
2569*3117ece4Schristos 
2570*3117ece4Schristos     if (HUF_isError(HUF_decompress(dst, litSize, ip+5, litCSize))) return ERROR(corruption_detected);
2571*3117ece4Schristos 
2572*3117ece4Schristos     *maxDstSizePtr = litSize;
2573*3117ece4Schristos     return litCSize + 5;
2574*3117ece4Schristos }
2575*3117ece4Schristos 
2576*3117ece4Schristos 
2577*3117ece4Schristos /** ZSTD_decodeLiteralsBlock
2578*3117ece4Schristos     @return : nb of bytes read from src (< srcSize ) */
2579*3117ece4Schristos static size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
2580*3117ece4Schristos                           const void* src, size_t srcSize)   /* note : srcSize < BLOCKSIZE */
2581*3117ece4Schristos {
2582*3117ece4Schristos     const BYTE* const istart = (const BYTE*) src;
2583*3117ece4Schristos 
2584*3117ece4Schristos     /* any compressed block with literals segment must be at least this size */
2585*3117ece4Schristos     if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected);
2586*3117ece4Schristos 
2587*3117ece4Schristos     switch(*istart & 3)
2588*3117ece4Schristos     {
2589*3117ece4Schristos     /* compressed */
2590*3117ece4Schristos     case 0:
2591*3117ece4Schristos         {
2592*3117ece4Schristos             size_t litSize = BLOCKSIZE;
2593*3117ece4Schristos             const size_t readSize = ZSTD_decompressLiterals(dctx->litBuffer, &litSize, src, srcSize);
2594*3117ece4Schristos             dctx->litPtr = dctx->litBuffer;
2595*3117ece4Schristos             dctx->litSize = litSize;
2596*3117ece4Schristos             memset(dctx->litBuffer + dctx->litSize, 0, 8);
2597*3117ece4Schristos             return readSize;   /* works if it's an error too */
2598*3117ece4Schristos         }
2599*3117ece4Schristos     case IS_RAW:
2600*3117ece4Schristos         {
2601*3117ece4Schristos             const size_t litSize = (MEM_readLE32(istart) & 0xFFFFFF) >> 2;   /* no buffer issue : srcSize >= MIN_CBLOCK_SIZE */
2602*3117ece4Schristos             if (litSize > srcSize-11)   /* risk of reading too far with wildcopy */
2603*3117ece4Schristos             {
2604*3117ece4Schristos                 if (litSize > BLOCKSIZE) return ERROR(corruption_detected);
2605*3117ece4Schristos                 if (litSize > srcSize-3) return ERROR(corruption_detected);
2606*3117ece4Schristos                 memcpy(dctx->litBuffer, istart, litSize);
2607*3117ece4Schristos                 dctx->litPtr = dctx->litBuffer;
2608*3117ece4Schristos                 dctx->litSize = litSize;
2609*3117ece4Schristos                 memset(dctx->litBuffer + dctx->litSize, 0, 8);
2610*3117ece4Schristos                 return litSize+3;
2611*3117ece4Schristos             }
2612*3117ece4Schristos             /* direct reference into compressed stream */
2613*3117ece4Schristos             dctx->litPtr = istart+3;
2614*3117ece4Schristos             dctx->litSize = litSize;
2615*3117ece4Schristos             return litSize+3;        }
2616*3117ece4Schristos     case IS_RLE:
2617*3117ece4Schristos         {
2618*3117ece4Schristos             const size_t litSize = (MEM_readLE32(istart) & 0xFFFFFF) >> 2;   /* no buffer issue : srcSize >= MIN_CBLOCK_SIZE */
2619*3117ece4Schristos             if (litSize > BLOCKSIZE) return ERROR(corruption_detected);
2620*3117ece4Schristos             memset(dctx->litBuffer, istart[3], litSize + 8);
2621*3117ece4Schristos             dctx->litPtr = dctx->litBuffer;
2622*3117ece4Schristos             dctx->litSize = litSize;
2623*3117ece4Schristos             return 4;
2624*3117ece4Schristos         }
2625*3117ece4Schristos     default:
2626*3117ece4Schristos         return ERROR(corruption_detected);   /* forbidden nominal case */
2627*3117ece4Schristos     }
2628*3117ece4Schristos }
2629*3117ece4Schristos 
2630*3117ece4Schristos 
2631*3117ece4Schristos static size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr,
2632*3117ece4Schristos                          FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb,
2633*3117ece4Schristos                          const void* src, size_t srcSize)
2634*3117ece4Schristos {
2635*3117ece4Schristos     const BYTE* const istart = (const BYTE* const)src;
2636*3117ece4Schristos     const BYTE* ip = istart;
2637*3117ece4Schristos     const BYTE* const iend = istart + srcSize;
2638*3117ece4Schristos     U32 LLtype, Offtype, MLtype;
2639*3117ece4Schristos     U32 LLlog, Offlog, MLlog;
2640*3117ece4Schristos     size_t dumpsLength;
2641*3117ece4Schristos 
2642*3117ece4Schristos     /* check */
2643*3117ece4Schristos     if (srcSize < 5) return ERROR(srcSize_wrong);
2644*3117ece4Schristos 
2645*3117ece4Schristos     /* SeqHead */
2646*3117ece4Schristos     *nbSeq = MEM_readLE16(ip); ip+=2;
2647*3117ece4Schristos     LLtype  = *ip >> 6;
2648*3117ece4Schristos     Offtype = (*ip >> 4) & 3;
2649*3117ece4Schristos     MLtype  = (*ip >> 2) & 3;
2650*3117ece4Schristos     if (*ip & 2)
2651*3117ece4Schristos     {
2652*3117ece4Schristos         dumpsLength  = ip[2];
2653*3117ece4Schristos         dumpsLength += ip[1] << 8;
2654*3117ece4Schristos         ip += 3;
2655*3117ece4Schristos     }
2656*3117ece4Schristos     else
2657*3117ece4Schristos     {
2658*3117ece4Schristos         dumpsLength  = ip[1];
2659*3117ece4Schristos         dumpsLength += (ip[0] & 1) << 8;
2660*3117ece4Schristos         ip += 2;
2661*3117ece4Schristos     }
2662*3117ece4Schristos     *dumpsPtr = ip;
2663*3117ece4Schristos     ip += dumpsLength;
2664*3117ece4Schristos     *dumpsLengthPtr = dumpsLength;
2665*3117ece4Schristos 
2666*3117ece4Schristos     /* check */
2667*3117ece4Schristos     if (ip > iend-3) return ERROR(srcSize_wrong); /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */
2668*3117ece4Schristos 
2669*3117ece4Schristos     /* sequences */
2670*3117ece4Schristos     {
2671*3117ece4Schristos         S16 norm[MaxML+1];    /* assumption : MaxML >= MaxLL >= MaxOff */
2672*3117ece4Schristos         size_t headerSize;
2673*3117ece4Schristos 
2674*3117ece4Schristos         /* Build DTables */
2675*3117ece4Schristos         switch(LLtype)
2676*3117ece4Schristos         {
2677*3117ece4Schristos         case bt_rle :
2678*3117ece4Schristos             LLlog = 0;
2679*3117ece4Schristos             FSE_buildDTable_rle(DTableLL, *ip++); break;
2680*3117ece4Schristos         case bt_raw :
2681*3117ece4Schristos             LLlog = LLbits;
2682*3117ece4Schristos             FSE_buildDTable_raw(DTableLL, LLbits); break;
2683*3117ece4Schristos         default :
2684*3117ece4Schristos             {   U32 max = MaxLL;
2685*3117ece4Schristos                 headerSize = FSE_readNCount(norm, &max, &LLlog, ip, iend-ip);
2686*3117ece4Schristos                 if (FSE_isError(headerSize)) return ERROR(GENERIC);
2687*3117ece4Schristos                 if (LLlog > LLFSELog) return ERROR(corruption_detected);
2688*3117ece4Schristos                 ip += headerSize;
2689*3117ece4Schristos                 FSE_buildDTable(DTableLL, norm, max, LLlog);
2690*3117ece4Schristos         }   }
2691*3117ece4Schristos 
2692*3117ece4Schristos         switch(Offtype)
2693*3117ece4Schristos         {
2694*3117ece4Schristos         case bt_rle :
2695*3117ece4Schristos             Offlog = 0;
2696*3117ece4Schristos             if (ip > iend-2) return ERROR(srcSize_wrong);   /* min : "raw", hence no header, but at least xxLog bits */
2697*3117ece4Schristos             FSE_buildDTable_rle(DTableOffb, *ip++ & MaxOff); /* if *ip > MaxOff, data is corrupted */
2698*3117ece4Schristos             break;
2699*3117ece4Schristos         case bt_raw :
2700*3117ece4Schristos             Offlog = Offbits;
2701*3117ece4Schristos             FSE_buildDTable_raw(DTableOffb, Offbits); break;
2702*3117ece4Schristos         default :
2703*3117ece4Schristos             {   U32 max = MaxOff;
2704*3117ece4Schristos                 headerSize = FSE_readNCount(norm, &max, &Offlog, ip, iend-ip);
2705*3117ece4Schristos                 if (FSE_isError(headerSize)) return ERROR(GENERIC);
2706*3117ece4Schristos                 if (Offlog > OffFSELog) return ERROR(corruption_detected);
2707*3117ece4Schristos                 ip += headerSize;
2708*3117ece4Schristos                 FSE_buildDTable(DTableOffb, norm, max, Offlog);
2709*3117ece4Schristos         }   }
2710*3117ece4Schristos 
2711*3117ece4Schristos         switch(MLtype)
2712*3117ece4Schristos         {
2713*3117ece4Schristos         case bt_rle :
2714*3117ece4Schristos             MLlog = 0;
2715*3117ece4Schristos             if (ip > iend-2) return ERROR(srcSize_wrong); /* min : "raw", hence no header, but at least xxLog bits */
2716*3117ece4Schristos             FSE_buildDTable_rle(DTableML, *ip++); break;
2717*3117ece4Schristos         case bt_raw :
2718*3117ece4Schristos             MLlog = MLbits;
2719*3117ece4Schristos             FSE_buildDTable_raw(DTableML, MLbits); break;
2720*3117ece4Schristos         default :
2721*3117ece4Schristos             {   U32 max = MaxML;
2722*3117ece4Schristos                 headerSize = FSE_readNCount(norm, &max, &MLlog, ip, iend-ip);
2723*3117ece4Schristos                 if (FSE_isError(headerSize)) return ERROR(GENERIC);
2724*3117ece4Schristos                 if (MLlog > MLFSELog) return ERROR(corruption_detected);
2725*3117ece4Schristos                 ip += headerSize;
2726*3117ece4Schristos                 FSE_buildDTable(DTableML, norm, max, MLlog);
2727*3117ece4Schristos     }   }   }
2728*3117ece4Schristos 
2729*3117ece4Schristos     return ip-istart;
2730*3117ece4Schristos }
2731*3117ece4Schristos 
2732*3117ece4Schristos 
2733*3117ece4Schristos typedef struct {
2734*3117ece4Schristos     size_t litLength;
2735*3117ece4Schristos     size_t offset;
2736*3117ece4Schristos     size_t matchLength;
2737*3117ece4Schristos } seq_t;
2738*3117ece4Schristos 
2739*3117ece4Schristos typedef struct {
2740*3117ece4Schristos     BIT_DStream_t DStream;
2741*3117ece4Schristos     FSE_DState_t stateLL;
2742*3117ece4Schristos     FSE_DState_t stateOffb;
2743*3117ece4Schristos     FSE_DState_t stateML;
2744*3117ece4Schristos     size_t prevOffset;
2745*3117ece4Schristos     const BYTE* dumps;
2746*3117ece4Schristos     const BYTE* dumpsEnd;
2747*3117ece4Schristos } seqState_t;
2748*3117ece4Schristos 
2749*3117ece4Schristos 
2750*3117ece4Schristos static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
2751*3117ece4Schristos {
2752*3117ece4Schristos     size_t litLength;
2753*3117ece4Schristos     size_t prevOffset;
2754*3117ece4Schristos     size_t offset;
2755*3117ece4Schristos     size_t matchLength;
2756*3117ece4Schristos     const BYTE* dumps = seqState->dumps;
2757*3117ece4Schristos     const BYTE* const de = seqState->dumpsEnd;
2758*3117ece4Schristos 
2759*3117ece4Schristos     /* Literal length */
2760*3117ece4Schristos     litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream));
2761*3117ece4Schristos     prevOffset = litLength ? seq->offset : seqState->prevOffset;
2762*3117ece4Schristos     if (litLength == MaxLL) {
2763*3117ece4Schristos         const U32 add = dumps<de ? *dumps++ : 0;
2764*3117ece4Schristos         if (add < 255) litLength += add;
2765*3117ece4Schristos         else if (dumps + 3 <= de) {
2766*3117ece4Schristos             litLength = MEM_readLE24(dumps);
2767*3117ece4Schristos             dumps += 3;
2768*3117ece4Schristos         }
2769*3117ece4Schristos         if (dumps >= de) { dumps = de-1; }  /* late correction, to avoid read overflow (data is now corrupted anyway) */
2770*3117ece4Schristos     }
2771*3117ece4Schristos 
2772*3117ece4Schristos     /* Offset */
2773*3117ece4Schristos     {   static const U32 offsetPrefix[MaxOff+1] = {
2774*3117ece4Schristos                 1 /*fake*/, 1, 2, 4, 8, 16, 32, 64, 128, 256,
2775*3117ece4Schristos                 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072, 262144,
2776*3117ece4Schristos                 524288, 1048576, 2097152, 4194304, 8388608, 16777216, 33554432, /*fake*/ 1, 1, 1, 1, 1 };
2777*3117ece4Schristos         U32 offsetCode, nbBits;
2778*3117ece4Schristos         offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream));   /* <= maxOff, by table construction */
2779*3117ece4Schristos         if (MEM_32bits()) BIT_reloadDStream(&(seqState->DStream));
2780*3117ece4Schristos         nbBits = offsetCode - 1;
2781*3117ece4Schristos         if (offsetCode==0) nbBits = 0;   /* cmove */
2782*3117ece4Schristos         offset = offsetPrefix[offsetCode] + BIT_readBits(&(seqState->DStream), nbBits);
2783*3117ece4Schristos         if (MEM_32bits()) BIT_reloadDStream(&(seqState->DStream));
2784*3117ece4Schristos         if (offsetCode==0) offset = prevOffset;   /* cmove */
2785*3117ece4Schristos         if (offsetCode | !litLength) seqState->prevOffset = seq->offset;   /* cmove */
2786*3117ece4Schristos     }
2787*3117ece4Schristos 
2788*3117ece4Schristos     /* MatchLength */
2789*3117ece4Schristos     matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream));
2790*3117ece4Schristos     if (matchLength == MaxML) {
2791*3117ece4Schristos         const U32 add = dumps<de ? *dumps++ : 0;
2792*3117ece4Schristos         if (add < 255) matchLength += add;
2793*3117ece4Schristos         else if (dumps + 3 <= de){
2794*3117ece4Schristos             matchLength = MEM_readLE24(dumps);
2795*3117ece4Schristos             dumps += 3;
2796*3117ece4Schristos         }
2797*3117ece4Schristos         if (dumps >= de) { dumps = de-1; }  /* late correction, to avoid read overflow (data is now corrupted anyway) */
2798*3117ece4Schristos     }
2799*3117ece4Schristos     matchLength += MINMATCH;
2800*3117ece4Schristos 
2801*3117ece4Schristos     /* save result */
2802*3117ece4Schristos     seq->litLength = litLength;
2803*3117ece4Schristos     seq->offset = offset;
2804*3117ece4Schristos     seq->matchLength = matchLength;
2805*3117ece4Schristos     seqState->dumps = dumps;
2806*3117ece4Schristos }
2807*3117ece4Schristos 
2808*3117ece4Schristos 
2809*3117ece4Schristos static size_t ZSTD_execSequence(BYTE* op,
2810*3117ece4Schristos                                 BYTE* const oend, seq_t sequence,
2811*3117ece4Schristos                                 const BYTE** litPtr, const BYTE* const litLimit,
2812*3117ece4Schristos                                 const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd)
2813*3117ece4Schristos {
2814*3117ece4Schristos     static const int dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 };   /* added */
2815*3117ece4Schristos     static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 };   /* subtracted */
2816*3117ece4Schristos     BYTE* const oLitEnd = op + sequence.litLength;
2817*3117ece4Schristos     const size_t sequenceLength = sequence.litLength + sequence.matchLength;
2818*3117ece4Schristos     BYTE* const oMatchEnd = op + sequenceLength;   /* risk : address space overflow (32-bits) */
2819*3117ece4Schristos     BYTE* const oend_8 = oend-8;
2820*3117ece4Schristos     const BYTE* const litEnd = *litPtr + sequence.litLength;
2821*3117ece4Schristos     const BYTE* match = oLitEnd - sequence.offset;
2822*3117ece4Schristos 
2823*3117ece4Schristos     /* checks */
2824*3117ece4Schristos     size_t const seqLength = sequence.litLength + sequence.matchLength;
2825*3117ece4Schristos 
2826*3117ece4Schristos     if (seqLength > (size_t)(oend - op)) return ERROR(dstSize_tooSmall);
2827*3117ece4Schristos     if (sequence.litLength > (size_t)(litLimit - *litPtr)) return ERROR(corruption_detected);
2828*3117ece4Schristos     /* Now we know there are no overflow in literal nor match lengths, can use pointer checks */
2829*3117ece4Schristos     if (oLitEnd > oend_8) return ERROR(dstSize_tooSmall);
2830*3117ece4Schristos 
2831*3117ece4Schristos     if (oMatchEnd > oend) return ERROR(dstSize_tooSmall);   /* overwrite beyond dst buffer */
2832*3117ece4Schristos     if (litEnd > litLimit) return ERROR(corruption_detected);   /* overRead beyond lit buffer */
2833*3117ece4Schristos 
2834*3117ece4Schristos     /* copy Literals */
2835*3117ece4Schristos     ZSTD_wildcopy(op, *litPtr, (ptrdiff_t)sequence.litLength);   /* note : oLitEnd <= oend-8 : no risk of overwrite beyond oend */
2836*3117ece4Schristos     op = oLitEnd;
2837*3117ece4Schristos     *litPtr = litEnd;   /* update for next sequence */
2838*3117ece4Schristos 
2839*3117ece4Schristos     /* copy Match */
2840*3117ece4Schristos     if (sequence.offset > (size_t)(oLitEnd - base))
2841*3117ece4Schristos     {
2842*3117ece4Schristos         /* offset beyond prefix */
2843*3117ece4Schristos         if (sequence.offset > (size_t)(oLitEnd - vBase))
2844*3117ece4Schristos             return ERROR(corruption_detected);
2845*3117ece4Schristos         match = dictEnd - (base-match);
2846*3117ece4Schristos         if (match + sequence.matchLength <= dictEnd)
2847*3117ece4Schristos         {
2848*3117ece4Schristos             memmove(oLitEnd, match, sequence.matchLength);
2849*3117ece4Schristos             return sequenceLength;
2850*3117ece4Schristos         }
2851*3117ece4Schristos         /* span extDict & currentPrefixSegment */
2852*3117ece4Schristos         {
2853*3117ece4Schristos             size_t length1 = dictEnd - match;
2854*3117ece4Schristos             memmove(oLitEnd, match, length1);
2855*3117ece4Schristos             op = oLitEnd + length1;
2856*3117ece4Schristos             sequence.matchLength -= length1;
2857*3117ece4Schristos             match = base;
2858*3117ece4Schristos             if (op > oend_8 || sequence.matchLength < MINMATCH) {
2859*3117ece4Schristos               while (op < oMatchEnd) *op++ = *match++;
2860*3117ece4Schristos               return sequenceLength;
2861*3117ece4Schristos             }
2862*3117ece4Schristos         }
2863*3117ece4Schristos     }
2864*3117ece4Schristos     /* Requirement: op <= oend_8 */
2865*3117ece4Schristos 
2866*3117ece4Schristos     /* match within prefix */
2867*3117ece4Schristos     if (sequence.offset < 8) {
2868*3117ece4Schristos         /* close range match, overlap */
2869*3117ece4Schristos         const int sub2 = dec64table[sequence.offset];
2870*3117ece4Schristos         op[0] = match[0];
2871*3117ece4Schristos         op[1] = match[1];
2872*3117ece4Schristos         op[2] = match[2];
2873*3117ece4Schristos         op[3] = match[3];
2874*3117ece4Schristos         match += dec32table[sequence.offset];
2875*3117ece4Schristos         ZSTD_copy4(op+4, match);
2876*3117ece4Schristos         match -= sub2;
2877*3117ece4Schristos     } else {
2878*3117ece4Schristos         ZSTD_copy8(op, match);
2879*3117ece4Schristos     }
2880*3117ece4Schristos     op += 8; match += 8;
2881*3117ece4Schristos 
2882*3117ece4Schristos     if (oMatchEnd > oend-(16-MINMATCH))
2883*3117ece4Schristos     {
2884*3117ece4Schristos         if (op < oend_8)
2885*3117ece4Schristos         {
2886*3117ece4Schristos             ZSTD_wildcopy(op, match, oend_8 - op);
2887*3117ece4Schristos             match += oend_8 - op;
2888*3117ece4Schristos             op = oend_8;
2889*3117ece4Schristos         }
2890*3117ece4Schristos         while (op < oMatchEnd) *op++ = *match++;
2891*3117ece4Schristos     }
2892*3117ece4Schristos     else
2893*3117ece4Schristos     {
2894*3117ece4Schristos         ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength-8);   /* works even if matchLength < 8, but must be signed */
2895*3117ece4Schristos     }
2896*3117ece4Schristos     return sequenceLength;
2897*3117ece4Schristos }
2898*3117ece4Schristos 
2899*3117ece4Schristos 
2900*3117ece4Schristos static size_t ZSTD_decompressSequences(
2901*3117ece4Schristos                                ZSTD_DCtx* dctx,
2902*3117ece4Schristos                                void* dst, size_t maxDstSize,
2903*3117ece4Schristos                          const void* seqStart, size_t seqSize)
2904*3117ece4Schristos {
2905*3117ece4Schristos     const BYTE* ip = (const BYTE*)seqStart;
2906*3117ece4Schristos     const BYTE* const iend = ip + seqSize;
2907*3117ece4Schristos     BYTE* const ostart = (BYTE* const)dst;
2908*3117ece4Schristos     BYTE* op = ostart;
2909*3117ece4Schristos     BYTE* const oend = ostart + maxDstSize;
2910*3117ece4Schristos     size_t errorCode, dumpsLength;
2911*3117ece4Schristos     const BYTE* litPtr = dctx->litPtr;
2912*3117ece4Schristos     const BYTE* const litEnd = litPtr + dctx->litSize;
2913*3117ece4Schristos     int nbSeq;
2914*3117ece4Schristos     const BYTE* dumps;
2915*3117ece4Schristos     U32* DTableLL = dctx->LLTable;
2916*3117ece4Schristos     U32* DTableML = dctx->MLTable;
2917*3117ece4Schristos     U32* DTableOffb = dctx->OffTable;
2918*3117ece4Schristos     const BYTE* const base = (const BYTE*) (dctx->base);
2919*3117ece4Schristos     const BYTE* const vBase = (const BYTE*) (dctx->vBase);
2920*3117ece4Schristos     const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
2921*3117ece4Schristos 
2922*3117ece4Schristos     /* Build Decoding Tables */
2923*3117ece4Schristos     errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
2924*3117ece4Schristos                                       DTableLL, DTableML, DTableOffb,
2925*3117ece4Schristos                                       ip, iend-ip);
2926*3117ece4Schristos     if (ZSTD_isError(errorCode)) return errorCode;
2927*3117ece4Schristos     ip += errorCode;
2928*3117ece4Schristos 
2929*3117ece4Schristos     /* Regen sequences */
2930*3117ece4Schristos     {
2931*3117ece4Schristos         seq_t sequence;
2932*3117ece4Schristos         seqState_t seqState;
2933*3117ece4Schristos 
2934*3117ece4Schristos         memset(&sequence, 0, sizeof(sequence));
2935*3117ece4Schristos         sequence.offset = 4;
2936*3117ece4Schristos         seqState.dumps = dumps;
2937*3117ece4Schristos         seqState.dumpsEnd = dumps + dumpsLength;
2938*3117ece4Schristos         seqState.prevOffset = 4;
2939*3117ece4Schristos         errorCode = BIT_initDStream(&(seqState.DStream), ip, iend-ip);
2940*3117ece4Schristos         if (ERR_isError(errorCode)) return ERROR(corruption_detected);
2941*3117ece4Schristos         FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);
2942*3117ece4Schristos         FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb);
2943*3117ece4Schristos         FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML);
2944*3117ece4Schristos 
2945*3117ece4Schristos         for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; )
2946*3117ece4Schristos         {
2947*3117ece4Schristos             size_t oneSeqSize;
2948*3117ece4Schristos             nbSeq--;
2949*3117ece4Schristos             ZSTD_decodeSequence(&sequence, &seqState);
2950*3117ece4Schristos             oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
2951*3117ece4Schristos             if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
2952*3117ece4Schristos             op += oneSeqSize;
2953*3117ece4Schristos         }
2954*3117ece4Schristos 
2955*3117ece4Schristos         /* check if reached exact end */
2956*3117ece4Schristos         if ( !BIT_endOfDStream(&(seqState.DStream)) ) return ERROR(corruption_detected);   /* DStream should be entirely and exactly consumed; otherwise data is corrupted */
2957*3117ece4Schristos 
2958*3117ece4Schristos         /* last literal segment */
2959*3117ece4Schristos         {
2960*3117ece4Schristos             size_t lastLLSize = litEnd - litPtr;
2961*3117ece4Schristos             if (litPtr > litEnd) return ERROR(corruption_detected);
2962*3117ece4Schristos             if (op+lastLLSize > oend) return ERROR(dstSize_tooSmall);
2963*3117ece4Schristos             if (lastLLSize > 0) {
2964*3117ece4Schristos                 if (op != litPtr) memcpy(op, litPtr, lastLLSize);
2965*3117ece4Schristos                 op += lastLLSize;
2966*3117ece4Schristos             }
2967*3117ece4Schristos         }
2968*3117ece4Schristos     }
2969*3117ece4Schristos 
2970*3117ece4Schristos     return op-ostart;
2971*3117ece4Schristos }
2972*3117ece4Schristos 
2973*3117ece4Schristos 
2974*3117ece4Schristos static void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst)
2975*3117ece4Schristos {
2976*3117ece4Schristos     if (dst != dctx->previousDstEnd)   /* not contiguous */
2977*3117ece4Schristos     {
2978*3117ece4Schristos         dctx->dictEnd = dctx->previousDstEnd;
2979*3117ece4Schristos         dctx->vBase = (const char*)dst - ((const char*)(dctx->previousDstEnd) - (const char*)(dctx->base));
2980*3117ece4Schristos         dctx->base = dst;
2981*3117ece4Schristos         dctx->previousDstEnd = dst;
2982*3117ece4Schristos     }
2983*3117ece4Schristos }
2984*3117ece4Schristos 
2985*3117ece4Schristos 
2986*3117ece4Schristos static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
2987*3117ece4Schristos                             void* dst, size_t maxDstSize,
2988*3117ece4Schristos                       const void* src, size_t srcSize)
2989*3117ece4Schristos {
2990*3117ece4Schristos     /* blockType == blockCompressed */
2991*3117ece4Schristos     const BYTE* ip = (const BYTE*)src;
2992*3117ece4Schristos     size_t litCSize;
2993*3117ece4Schristos 
2994*3117ece4Schristos     if (srcSize > BLOCKSIZE) return ERROR(corruption_detected);
2995*3117ece4Schristos 
2996*3117ece4Schristos     /* Decode literals sub-block */
2997*3117ece4Schristos     litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize);
2998*3117ece4Schristos     if (ZSTD_isError(litCSize)) return litCSize;
2999*3117ece4Schristos     ip += litCSize;
3000*3117ece4Schristos     srcSize -= litCSize;
3001*3117ece4Schristos 
3002*3117ece4Schristos     return ZSTD_decompressSequences(dctx, dst, maxDstSize, ip, srcSize);
3003*3117ece4Schristos }
3004*3117ece4Schristos 
3005*3117ece4Schristos 
3006*3117ece4Schristos static size_t ZSTD_decompress_usingDict(ZSTD_DCtx* ctx,
3007*3117ece4Schristos                                  void* dst, size_t maxDstSize,
3008*3117ece4Schristos                                  const void* src, size_t srcSize,
3009*3117ece4Schristos                                  const void* dict, size_t dictSize)
3010*3117ece4Schristos {
3011*3117ece4Schristos     const BYTE* ip = (const BYTE*)src;
3012*3117ece4Schristos     const BYTE* iend = ip + srcSize;
3013*3117ece4Schristos     BYTE* const ostart = (BYTE* const)dst;
3014*3117ece4Schristos     BYTE* op = ostart;
3015*3117ece4Schristos     BYTE* const oend = ostart + maxDstSize;
3016*3117ece4Schristos     size_t remainingSize = srcSize;
3017*3117ece4Schristos     blockProperties_t blockProperties;
3018*3117ece4Schristos 
3019*3117ece4Schristos     /* init */
3020*3117ece4Schristos     ZSTD_resetDCtx(ctx);
3021*3117ece4Schristos     if (dict)
3022*3117ece4Schristos     {
3023*3117ece4Schristos         ZSTD_decompress_insertDictionary(ctx, dict, dictSize);
3024*3117ece4Schristos         ctx->dictEnd = ctx->previousDstEnd;
3025*3117ece4Schristos         ctx->vBase = (const char*)dst - ((const char*)(ctx->previousDstEnd) - (const char*)(ctx->base));
3026*3117ece4Schristos         ctx->base = dst;
3027*3117ece4Schristos     }
3028*3117ece4Schristos     else
3029*3117ece4Schristos     {
3030*3117ece4Schristos         ctx->vBase = ctx->base = ctx->dictEnd = dst;
3031*3117ece4Schristos     }
3032*3117ece4Schristos 
3033*3117ece4Schristos     /* Frame Header */
3034*3117ece4Schristos     {
3035*3117ece4Schristos         size_t frameHeaderSize;
3036*3117ece4Schristos         if (srcSize < ZSTD_frameHeaderSize_min+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
3037*3117ece4Schristos         frameHeaderSize = ZSTD_decodeFrameHeader_Part1(ctx, src, ZSTD_frameHeaderSize_min);
3038*3117ece4Schristos         if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
3039*3117ece4Schristos         if (srcSize < frameHeaderSize+ZSTD_blockHeaderSize) return ERROR(srcSize_wrong);
3040*3117ece4Schristos         ip += frameHeaderSize; remainingSize -= frameHeaderSize;
3041*3117ece4Schristos         frameHeaderSize = ZSTD_decodeFrameHeader_Part2(ctx, src, frameHeaderSize);
3042*3117ece4Schristos         if (ZSTD_isError(frameHeaderSize)) return frameHeaderSize;
3043*3117ece4Schristos     }
3044*3117ece4Schristos 
3045*3117ece4Schristos     /* Loop on each block */
3046*3117ece4Schristos     while (1)
3047*3117ece4Schristos     {
3048*3117ece4Schristos         size_t decodedSize=0;
3049*3117ece4Schristos         size_t cBlockSize = ZSTD_getcBlockSize(ip, iend-ip, &blockProperties);
3050*3117ece4Schristos         if (ZSTD_isError(cBlockSize)) return cBlockSize;
3051*3117ece4Schristos 
3052*3117ece4Schristos         ip += ZSTD_blockHeaderSize;
3053*3117ece4Schristos         remainingSize -= ZSTD_blockHeaderSize;
3054*3117ece4Schristos         if (cBlockSize > remainingSize) return ERROR(srcSize_wrong);
3055*3117ece4Schristos 
3056*3117ece4Schristos         switch(blockProperties.blockType)
3057*3117ece4Schristos         {
3058*3117ece4Schristos         case bt_compressed:
3059*3117ece4Schristos             decodedSize = ZSTD_decompressBlock_internal(ctx, op, oend-op, ip, cBlockSize);
3060*3117ece4Schristos             break;
3061*3117ece4Schristos         case bt_raw :
3062*3117ece4Schristos             decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize);
3063*3117ece4Schristos             break;
3064*3117ece4Schristos         case bt_rle :
3065*3117ece4Schristos             return ERROR(GENERIC);   /* not yet supported */
3066*3117ece4Schristos             break;
3067*3117ece4Schristos         case bt_end :
3068*3117ece4Schristos             /* end of frame */
3069*3117ece4Schristos             if (remainingSize) return ERROR(srcSize_wrong);
3070*3117ece4Schristos             break;
3071*3117ece4Schristos         default:
3072*3117ece4Schristos             return ERROR(GENERIC);   /* impossible */
3073*3117ece4Schristos         }
3074*3117ece4Schristos         if (cBlockSize == 0) break;   /* bt_end */
3075*3117ece4Schristos 
3076*3117ece4Schristos         if (ZSTD_isError(decodedSize)) return decodedSize;
3077*3117ece4Schristos         op += decodedSize;
3078*3117ece4Schristos         ip += cBlockSize;
3079*3117ece4Schristos         remainingSize -= cBlockSize;
3080*3117ece4Schristos     }
3081*3117ece4Schristos 
3082*3117ece4Schristos     return op-ostart;
3083*3117ece4Schristos }
3084*3117ece4Schristos 
3085*3117ece4Schristos /* ZSTD_errorFrameSizeInfoLegacy() :
3086*3117ece4Schristos    assumes `cSize` and `dBound` are _not_ NULL */
3087*3117ece4Schristos static void ZSTD_errorFrameSizeInfoLegacy(size_t* cSize, unsigned long long* dBound, size_t ret)
3088*3117ece4Schristos {
3089*3117ece4Schristos     *cSize = ret;
3090*3117ece4Schristos     *dBound = ZSTD_CONTENTSIZE_ERROR;
3091*3117ece4Schristos }
3092*3117ece4Schristos 
3093*3117ece4Schristos void ZSTDv04_findFrameSizeInfoLegacy(const void *src, size_t srcSize, size_t* cSize, unsigned long long* dBound)
3094*3117ece4Schristos {
3095*3117ece4Schristos     const BYTE* ip = (const BYTE*)src;
3096*3117ece4Schristos     size_t remainingSize = srcSize;
3097*3117ece4Schristos     size_t nbBlocks = 0;
3098*3117ece4Schristos     blockProperties_t blockProperties;
3099*3117ece4Schristos 
3100*3117ece4Schristos     /* Frame Header */
3101*3117ece4Schristos     if (srcSize < ZSTD_frameHeaderSize_min) {
3102*3117ece4Schristos         ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
3103*3117ece4Schristos         return;
3104*3117ece4Schristos     }
3105*3117ece4Schristos     if (MEM_readLE32(src) != ZSTD_MAGICNUMBER) {
3106*3117ece4Schristos         ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(prefix_unknown));
3107*3117ece4Schristos         return;
3108*3117ece4Schristos     }
3109*3117ece4Schristos     ip += ZSTD_frameHeaderSize_min; remainingSize -= ZSTD_frameHeaderSize_min;
3110*3117ece4Schristos 
3111*3117ece4Schristos     /* Loop on each block */
3112*3117ece4Schristos     while (1)
3113*3117ece4Schristos     {
3114*3117ece4Schristos         size_t cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties);
3115*3117ece4Schristos         if (ZSTD_isError(cBlockSize)) {
3116*3117ece4Schristos             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, cBlockSize);
3117*3117ece4Schristos             return;
3118*3117ece4Schristos         }
3119*3117ece4Schristos 
3120*3117ece4Schristos         ip += ZSTD_blockHeaderSize;
3121*3117ece4Schristos         remainingSize -= ZSTD_blockHeaderSize;
3122*3117ece4Schristos         if (cBlockSize > remainingSize) {
3123*3117ece4Schristos             ZSTD_errorFrameSizeInfoLegacy(cSize, dBound, ERROR(srcSize_wrong));
3124*3117ece4Schristos             return;
3125*3117ece4Schristos         }
3126*3117ece4Schristos 
3127*3117ece4Schristos         if (cBlockSize == 0) break;   /* bt_end */
3128*3117ece4Schristos 
3129*3117ece4Schristos         ip += cBlockSize;
3130*3117ece4Schristos         remainingSize -= cBlockSize;
3131*3117ece4Schristos         nbBlocks++;
3132*3117ece4Schristos     }
3133*3117ece4Schristos 
3134*3117ece4Schristos     *cSize = ip - (const BYTE*)src;
3135*3117ece4Schristos     *dBound = nbBlocks * BLOCKSIZE;
3136*3117ece4Schristos }
3137*3117ece4Schristos 
3138*3117ece4Schristos /* ******************************
3139*3117ece4Schristos *  Streaming Decompression API
3140*3117ece4Schristos ********************************/
3141*3117ece4Schristos static size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx* dctx)
3142*3117ece4Schristos {
3143*3117ece4Schristos     return dctx->expected;
3144*3117ece4Schristos }
3145*3117ece4Schristos 
3146*3117ece4Schristos static size_t ZSTD_decompressContinue(ZSTD_DCtx* ctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
3147*3117ece4Schristos {
3148*3117ece4Schristos     /* Sanity check */
3149*3117ece4Schristos     if (srcSize != ctx->expected) return ERROR(srcSize_wrong);
3150*3117ece4Schristos     ZSTD_checkContinuity(ctx, dst);
3151*3117ece4Schristos 
3152*3117ece4Schristos     /* Decompress : frame header; part 1 */
3153*3117ece4Schristos     switch (ctx->stage)
3154*3117ece4Schristos     {
3155*3117ece4Schristos     case ZSTDds_getFrameHeaderSize :
3156*3117ece4Schristos         /* get frame header size */
3157*3117ece4Schristos         if (srcSize != ZSTD_frameHeaderSize_min) return ERROR(srcSize_wrong);   /* impossible */
3158*3117ece4Schristos         ctx->headerSize = ZSTD_decodeFrameHeader_Part1(ctx, src, ZSTD_frameHeaderSize_min);
3159*3117ece4Schristos         if (ZSTD_isError(ctx->headerSize)) return ctx->headerSize;
3160*3117ece4Schristos         memcpy(ctx->headerBuffer, src, ZSTD_frameHeaderSize_min);
3161*3117ece4Schristos         if (ctx->headerSize > ZSTD_frameHeaderSize_min) return ERROR(GENERIC);   /* impossible */
3162*3117ece4Schristos         ctx->expected = 0;   /* not necessary to copy more */
3163*3117ece4Schristos         /* fallthrough */
3164*3117ece4Schristos     case ZSTDds_decodeFrameHeader:
3165*3117ece4Schristos         /* get frame header */
3166*3117ece4Schristos         {   size_t const result = ZSTD_decodeFrameHeader_Part2(ctx, ctx->headerBuffer, ctx->headerSize);
3167*3117ece4Schristos             if (ZSTD_isError(result)) return result;
3168*3117ece4Schristos             ctx->expected = ZSTD_blockHeaderSize;
3169*3117ece4Schristos             ctx->stage = ZSTDds_decodeBlockHeader;
3170*3117ece4Schristos             return 0;
3171*3117ece4Schristos         }
3172*3117ece4Schristos     case ZSTDds_decodeBlockHeader:
3173*3117ece4Schristos         /* Decode block header */
3174*3117ece4Schristos         {   blockProperties_t bp;
3175*3117ece4Schristos             size_t const blockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp);
3176*3117ece4Schristos             if (ZSTD_isError(blockSize)) return blockSize;
3177*3117ece4Schristos             if (bp.blockType == bt_end)
3178*3117ece4Schristos             {
3179*3117ece4Schristos                 ctx->expected = 0;
3180*3117ece4Schristos                 ctx->stage = ZSTDds_getFrameHeaderSize;
3181*3117ece4Schristos             }
3182*3117ece4Schristos             else
3183*3117ece4Schristos             {
3184*3117ece4Schristos                 ctx->expected = blockSize;
3185*3117ece4Schristos                 ctx->bType = bp.blockType;
3186*3117ece4Schristos                 ctx->stage = ZSTDds_decompressBlock;
3187*3117ece4Schristos             }
3188*3117ece4Schristos             return 0;
3189*3117ece4Schristos         }
3190*3117ece4Schristos     case ZSTDds_decompressBlock:
3191*3117ece4Schristos         {
3192*3117ece4Schristos             /* Decompress : block content */
3193*3117ece4Schristos             size_t rSize;
3194*3117ece4Schristos             switch(ctx->bType)
3195*3117ece4Schristos             {
3196*3117ece4Schristos             case bt_compressed:
3197*3117ece4Schristos                 rSize = ZSTD_decompressBlock_internal(ctx, dst, maxDstSize, src, srcSize);
3198*3117ece4Schristos                 break;
3199*3117ece4Schristos             case bt_raw :
3200*3117ece4Schristos                 rSize = ZSTD_copyRawBlock(dst, maxDstSize, src, srcSize);
3201*3117ece4Schristos                 break;
3202*3117ece4Schristos             case bt_rle :
3203*3117ece4Schristos                 return ERROR(GENERIC);   /* not yet handled */
3204*3117ece4Schristos                 break;
3205*3117ece4Schristos             case bt_end :   /* should never happen (filtered at phase 1) */
3206*3117ece4Schristos                 rSize = 0;
3207*3117ece4Schristos                 break;
3208*3117ece4Schristos             default:
3209*3117ece4Schristos                 return ERROR(GENERIC);
3210*3117ece4Schristos             }
3211*3117ece4Schristos             ctx->stage = ZSTDds_decodeBlockHeader;
3212*3117ece4Schristos             ctx->expected = ZSTD_blockHeaderSize;
3213*3117ece4Schristos             if (ZSTD_isError(rSize)) return rSize;
3214*3117ece4Schristos             ctx->previousDstEnd = (char*)dst + rSize;
3215*3117ece4Schristos             return rSize;
3216*3117ece4Schristos         }
3217*3117ece4Schristos     default:
3218*3117ece4Schristos         return ERROR(GENERIC);   /* impossible */
3219*3117ece4Schristos     }
3220*3117ece4Schristos }
3221*3117ece4Schristos 
3222*3117ece4Schristos 
3223*3117ece4Schristos static void ZSTD_decompress_insertDictionary(ZSTD_DCtx* ctx, const void* dict, size_t dictSize)
3224*3117ece4Schristos {
3225*3117ece4Schristos     ctx->dictEnd = ctx->previousDstEnd;
3226*3117ece4Schristos     ctx->vBase = (const char*)dict - ((const char*)(ctx->previousDstEnd) - (const char*)(ctx->base));
3227*3117ece4Schristos     ctx->base = dict;
3228*3117ece4Schristos     ctx->previousDstEnd = (const char*)dict + dictSize;
3229*3117ece4Schristos }
3230*3117ece4Schristos 
3231*3117ece4Schristos 
3232*3117ece4Schristos 
3233*3117ece4Schristos /*
3234*3117ece4Schristos     Buffered version of Zstd compression library
3235*3117ece4Schristos     Copyright (C) 2015, Yann Collet.
3236*3117ece4Schristos 
3237*3117ece4Schristos     BSD 2-Clause License (https://opensource.org/licenses/bsd-license.php)
3238*3117ece4Schristos 
3239*3117ece4Schristos     Redistribution and use in source and binary forms, with or without
3240*3117ece4Schristos     modification, are permitted provided that the following conditions are
3241*3117ece4Schristos     met:
3242*3117ece4Schristos     * Redistributions of source code must retain the above copyright
3243*3117ece4Schristos     notice, this list of conditions and the following disclaimer.
3244*3117ece4Schristos     * Redistributions in binary form must reproduce the above
3245*3117ece4Schristos     copyright notice, this list of conditions and the following disclaimer
3246*3117ece4Schristos     in the documentation and/or other materials provided with the
3247*3117ece4Schristos     distribution.
3248*3117ece4Schristos     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
3249*3117ece4Schristos     "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
3250*3117ece4Schristos     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
3251*3117ece4Schristos     A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
3252*3117ece4Schristos     OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
3253*3117ece4Schristos     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
3254*3117ece4Schristos     LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
3255*3117ece4Schristos     DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
3256*3117ece4Schristos     THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
3257*3117ece4Schristos     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
3258*3117ece4Schristos     OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
3259*3117ece4Schristos 
3260*3117ece4Schristos     You can contact the author at :
3261*3117ece4Schristos     - zstd source repository : https://github.com/Cyan4973/zstd
3262*3117ece4Schristos     - ztsd public forum : https://groups.google.com/forum/#!forum/lz4c
3263*3117ece4Schristos */
3264*3117ece4Schristos 
3265*3117ece4Schristos /* The objects defined into this file should be considered experimental.
3266*3117ece4Schristos  * They are not labelled stable, as their prototype may change in the future.
3267*3117ece4Schristos  * You can use them for tests, provide feedback, or if you can endure risk of future changes.
3268*3117ece4Schristos  */
3269*3117ece4Schristos 
3270*3117ece4Schristos /* *************************************
3271*3117ece4Schristos *  Includes
3272*3117ece4Schristos ***************************************/
3273*3117ece4Schristos #include <stdlib.h>
3274*3117ece4Schristos 
3275*3117ece4Schristos 
3276*3117ece4Schristos /** ************************************************
3277*3117ece4Schristos *  Streaming decompression
3278*3117ece4Schristos *
3279*3117ece4Schristos *  A ZBUFF_DCtx object is required to track streaming operation.
3280*3117ece4Schristos *  Use ZBUFF_createDCtx() and ZBUFF_freeDCtx() to create/release resources.
3281*3117ece4Schristos *  Use ZBUFF_decompressInit() to start a new decompression operation.
3282*3117ece4Schristos *  ZBUFF_DCtx objects can be reused multiple times.
3283*3117ece4Schristos *
3284*3117ece4Schristos *  Use ZBUFF_decompressContinue() repetitively to consume your input.
3285*3117ece4Schristos *  *srcSizePtr and *maxDstSizePtr can be any size.
3286*3117ece4Schristos *  The function will report how many bytes were read or written by modifying *srcSizePtr and *maxDstSizePtr.
3287*3117ece4Schristos *  Note that it may not consume the entire input, in which case it's up to the caller to call again the function with remaining input.
3288*3117ece4Schristos *  The content of dst will be overwritten (up to *maxDstSizePtr) at each function call, so save its content if it matters or change dst .
3289*3117ece4Schristos *  return : a hint to preferred nb of bytes to use as input for next function call (it's only a hint, to improve latency)
3290*3117ece4Schristos *            or 0 when a frame is completely decoded
3291*3117ece4Schristos *            or an error code, which can be tested using ZBUFF_isError().
3292*3117ece4Schristos *
3293*3117ece4Schristos *  Hint : recommended buffer sizes (not compulsory)
3294*3117ece4Schristos *  output : 128 KB block size is the internal unit, it ensures it's always possible to write a full block when it's decoded.
3295*3117ece4Schristos *  input : just follow indications from ZBUFF_decompressContinue() to minimize latency. It should always be <= 128 KB + 3 .
3296*3117ece4Schristos * **************************************************/
3297*3117ece4Schristos 
3298*3117ece4Schristos typedef enum { ZBUFFds_init, ZBUFFds_readHeader, ZBUFFds_loadHeader, ZBUFFds_decodeHeader,
3299*3117ece4Schristos                ZBUFFds_read, ZBUFFds_load, ZBUFFds_flush } ZBUFF_dStage;
3300*3117ece4Schristos 
3301*3117ece4Schristos /* *** Resource management *** */
3302*3117ece4Schristos 
3303*3117ece4Schristos #define ZSTD_frameHeaderSize_max 5   /* too magical, should come from reference */
3304*3117ece4Schristos struct ZBUFFv04_DCtx_s {
3305*3117ece4Schristos     ZSTD_DCtx* zc;
3306*3117ece4Schristos     ZSTD_parameters params;
3307*3117ece4Schristos     char* inBuff;
3308*3117ece4Schristos     size_t inBuffSize;
3309*3117ece4Schristos     size_t inPos;
3310*3117ece4Schristos     char* outBuff;
3311*3117ece4Schristos     size_t outBuffSize;
3312*3117ece4Schristos     size_t outStart;
3313*3117ece4Schristos     size_t outEnd;
3314*3117ece4Schristos     size_t hPos;
3315*3117ece4Schristos     const char* dict;
3316*3117ece4Schristos     size_t dictSize;
3317*3117ece4Schristos     ZBUFF_dStage stage;
3318*3117ece4Schristos     unsigned char headerBuffer[ZSTD_frameHeaderSize_max];
3319*3117ece4Schristos };   /* typedef'd to ZBUFF_DCtx within "zstd_buffered.h" */
3320*3117ece4Schristos 
3321*3117ece4Schristos typedef ZBUFFv04_DCtx ZBUFF_DCtx;
3322*3117ece4Schristos 
3323*3117ece4Schristos 
3324*3117ece4Schristos static ZBUFF_DCtx* ZBUFF_createDCtx(void)
3325*3117ece4Schristos {
3326*3117ece4Schristos     ZBUFF_DCtx* zbc = (ZBUFF_DCtx*)malloc(sizeof(ZBUFF_DCtx));
3327*3117ece4Schristos     if (zbc==NULL) return NULL;
3328*3117ece4Schristos     memset(zbc, 0, sizeof(*zbc));
3329*3117ece4Schristos     zbc->zc = ZSTD_createDCtx();
3330*3117ece4Schristos     zbc->stage = ZBUFFds_init;
3331*3117ece4Schristos     return zbc;
3332*3117ece4Schristos }
3333*3117ece4Schristos 
3334*3117ece4Schristos static size_t ZBUFF_freeDCtx(ZBUFF_DCtx* zbc)
3335*3117ece4Schristos {
3336*3117ece4Schristos     if (zbc==NULL) return 0;   /* support free on null */
3337*3117ece4Schristos     ZSTD_freeDCtx(zbc->zc);
3338*3117ece4Schristos     free(zbc->inBuff);
3339*3117ece4Schristos     free(zbc->outBuff);
3340*3117ece4Schristos     free(zbc);
3341*3117ece4Schristos     return 0;
3342*3117ece4Schristos }
3343*3117ece4Schristos 
3344*3117ece4Schristos 
3345*3117ece4Schristos /* *** Initialization *** */
3346*3117ece4Schristos 
3347*3117ece4Schristos static size_t ZBUFF_decompressInit(ZBUFF_DCtx* zbc)
3348*3117ece4Schristos {
3349*3117ece4Schristos     zbc->stage = ZBUFFds_readHeader;
3350*3117ece4Schristos     zbc->hPos = zbc->inPos = zbc->outStart = zbc->outEnd = zbc->dictSize = 0;
3351*3117ece4Schristos     return ZSTD_resetDCtx(zbc->zc);
3352*3117ece4Schristos }
3353*3117ece4Schristos 
3354*3117ece4Schristos 
3355*3117ece4Schristos static size_t ZBUFF_decompressWithDictionary(ZBUFF_DCtx* zbc, const void* src, size_t srcSize)
3356*3117ece4Schristos {
3357*3117ece4Schristos     zbc->dict = (const char*)src;
3358*3117ece4Schristos     zbc->dictSize = srcSize;
3359*3117ece4Schristos     return 0;
3360*3117ece4Schristos }
3361*3117ece4Schristos 
3362*3117ece4Schristos static size_t ZBUFF_limitCopy(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
3363*3117ece4Schristos {
3364*3117ece4Schristos     size_t length = MIN(maxDstSize, srcSize);
3365*3117ece4Schristos     if (length > 0) {
3366*3117ece4Schristos         memcpy(dst, src, length);
3367*3117ece4Schristos     }
3368*3117ece4Schristos     return length;
3369*3117ece4Schristos }
3370*3117ece4Schristos 
3371*3117ece4Schristos /* *** Decompression *** */
3372*3117ece4Schristos 
3373*3117ece4Schristos static size_t ZBUFF_decompressContinue(ZBUFF_DCtx* zbc, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr)
3374*3117ece4Schristos {
3375*3117ece4Schristos     const char* const istart = (const char*)src;
3376*3117ece4Schristos     const char* ip = istart;
3377*3117ece4Schristos     const char* const iend = istart + *srcSizePtr;
3378*3117ece4Schristos     char* const ostart = (char*)dst;
3379*3117ece4Schristos     char* op = ostart;
3380*3117ece4Schristos     char* const oend = ostart + *maxDstSizePtr;
3381*3117ece4Schristos     U32 notDone = 1;
3382*3117ece4Schristos 
3383*3117ece4Schristos     DEBUGLOG(5, "ZBUFF_decompressContinue");
3384*3117ece4Schristos     while (notDone)
3385*3117ece4Schristos     {
3386*3117ece4Schristos         switch(zbc->stage)
3387*3117ece4Schristos         {
3388*3117ece4Schristos 
3389*3117ece4Schristos         case ZBUFFds_init :
3390*3117ece4Schristos             DEBUGLOG(5, "ZBUFF_decompressContinue: stage==ZBUFFds_init => ERROR(init_missing)");
3391*3117ece4Schristos             return ERROR(init_missing);
3392*3117ece4Schristos 
3393*3117ece4Schristos         case ZBUFFds_readHeader :
3394*3117ece4Schristos             /* read header from src */
3395*3117ece4Schristos             {   size_t const headerSize = ZSTD_getFrameParams(&(zbc->params), src, *srcSizePtr);
3396*3117ece4Schristos                 if (ZSTD_isError(headerSize)) return headerSize;
3397*3117ece4Schristos                 if (headerSize) {
3398*3117ece4Schristos                     /* not enough input to decode header : tell how many bytes would be necessary */
3399*3117ece4Schristos                     memcpy(zbc->headerBuffer+zbc->hPos, src, *srcSizePtr);
3400*3117ece4Schristos                     zbc->hPos += *srcSizePtr;
3401*3117ece4Schristos                     *maxDstSizePtr = 0;
3402*3117ece4Schristos                     zbc->stage = ZBUFFds_loadHeader;
3403*3117ece4Schristos                     return headerSize - zbc->hPos;
3404*3117ece4Schristos                 }
3405*3117ece4Schristos                 zbc->stage = ZBUFFds_decodeHeader;
3406*3117ece4Schristos                 break;
3407*3117ece4Schristos             }
3408*3117ece4Schristos 
3409*3117ece4Schristos         case ZBUFFds_loadHeader:
3410*3117ece4Schristos             /* complete header from src */
3411*3117ece4Schristos             {   size_t headerSize = ZBUFF_limitCopy(
3412*3117ece4Schristos                     zbc->headerBuffer + zbc->hPos, ZSTD_frameHeaderSize_max - zbc->hPos,
3413*3117ece4Schristos                     src, *srcSizePtr);
3414*3117ece4Schristos                 zbc->hPos += headerSize;
3415*3117ece4Schristos                 ip += headerSize;
3416*3117ece4Schristos                 headerSize = ZSTD_getFrameParams(&(zbc->params), zbc->headerBuffer, zbc->hPos);
3417*3117ece4Schristos                 if (ZSTD_isError(headerSize)) return headerSize;
3418*3117ece4Schristos                 if (headerSize) {
3419*3117ece4Schristos                     /* not enough input to decode header : tell how many bytes would be necessary */
3420*3117ece4Schristos                     *maxDstSizePtr = 0;
3421*3117ece4Schristos                     return headerSize - zbc->hPos;
3422*3117ece4Schristos             }   }
3423*3117ece4Schristos             /* intentional fallthrough */
3424*3117ece4Schristos 
3425*3117ece4Schristos         case ZBUFFds_decodeHeader:
3426*3117ece4Schristos                 /* apply header to create / resize buffers */
3427*3117ece4Schristos                 {   size_t const neededOutSize = (size_t)1 << zbc->params.windowLog;
3428*3117ece4Schristos                     size_t const neededInSize = BLOCKSIZE;   /* a block is never > BLOCKSIZE */
3429*3117ece4Schristos                     if (zbc->inBuffSize < neededInSize) {
3430*3117ece4Schristos                         free(zbc->inBuff);
3431*3117ece4Schristos                         zbc->inBuffSize = neededInSize;
3432*3117ece4Schristos                         zbc->inBuff = (char*)malloc(neededInSize);
3433*3117ece4Schristos                         if (zbc->inBuff == NULL) return ERROR(memory_allocation);
3434*3117ece4Schristos                     }
3435*3117ece4Schristos                     if (zbc->outBuffSize < neededOutSize) {
3436*3117ece4Schristos                         free(zbc->outBuff);
3437*3117ece4Schristos                         zbc->outBuffSize = neededOutSize;
3438*3117ece4Schristos                         zbc->outBuff = (char*)malloc(neededOutSize);
3439*3117ece4Schristos                         if (zbc->outBuff == NULL) return ERROR(memory_allocation);
3440*3117ece4Schristos                 }   }
3441*3117ece4Schristos                 if (zbc->dictSize)
3442*3117ece4Schristos                     ZSTD_decompress_insertDictionary(zbc->zc, zbc->dict, zbc->dictSize);
3443*3117ece4Schristos                 if (zbc->hPos) {
3444*3117ece4Schristos                     /* some data already loaded into headerBuffer : transfer into inBuff */
3445*3117ece4Schristos                     memcpy(zbc->inBuff, zbc->headerBuffer, zbc->hPos);
3446*3117ece4Schristos                     zbc->inPos = zbc->hPos;
3447*3117ece4Schristos                     zbc->hPos = 0;
3448*3117ece4Schristos                     zbc->stage = ZBUFFds_load;
3449*3117ece4Schristos                     break;
3450*3117ece4Schristos                 }
3451*3117ece4Schristos                 zbc->stage = ZBUFFds_read;
3452*3117ece4Schristos 		/* fall-through */
3453*3117ece4Schristos         case ZBUFFds_read:
3454*3117ece4Schristos             {
3455*3117ece4Schristos                 size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
3456*3117ece4Schristos                 if (neededInSize==0)   /* end of frame */
3457*3117ece4Schristos                 {
3458*3117ece4Schristos                     zbc->stage = ZBUFFds_init;
3459*3117ece4Schristos                     notDone = 0;
3460*3117ece4Schristos                     break;
3461*3117ece4Schristos                 }
3462*3117ece4Schristos                 if ((size_t)(iend-ip) >= neededInSize)
3463*3117ece4Schristos                 {
3464*3117ece4Schristos                     /* directly decode from src */
3465*3117ece4Schristos                     size_t decodedSize = ZSTD_decompressContinue(zbc->zc,
3466*3117ece4Schristos                         zbc->outBuff + zbc->outStart, zbc->outBuffSize - zbc->outStart,
3467*3117ece4Schristos                         ip, neededInSize);
3468*3117ece4Schristos                     if (ZSTD_isError(decodedSize)) return decodedSize;
3469*3117ece4Schristos                     ip += neededInSize;
3470*3117ece4Schristos                     if (!decodedSize) break;   /* this was just a header */
3471*3117ece4Schristos                     zbc->outEnd = zbc->outStart +  decodedSize;
3472*3117ece4Schristos                     zbc->stage = ZBUFFds_flush;
3473*3117ece4Schristos                     break;
3474*3117ece4Schristos                 }
3475*3117ece4Schristos                 if (ip==iend) { notDone = 0; break; }   /* no more input */
3476*3117ece4Schristos                 zbc->stage = ZBUFFds_load;
3477*3117ece4Schristos             }
3478*3117ece4Schristos 	    /* fall-through */
3479*3117ece4Schristos         case ZBUFFds_load:
3480*3117ece4Schristos             {
3481*3117ece4Schristos                 size_t neededInSize = ZSTD_nextSrcSizeToDecompress(zbc->zc);
3482*3117ece4Schristos                 size_t toLoad = neededInSize - zbc->inPos;   /* should always be <= remaining space within inBuff */
3483*3117ece4Schristos                 size_t loadedSize;
3484*3117ece4Schristos                 if (toLoad > zbc->inBuffSize - zbc->inPos) return ERROR(corruption_detected);   /* should never happen */
3485*3117ece4Schristos                 loadedSize = ZBUFF_limitCopy(zbc->inBuff + zbc->inPos, toLoad, ip, iend-ip);
3486*3117ece4Schristos                 ip += loadedSize;
3487*3117ece4Schristos                 zbc->inPos += loadedSize;
3488*3117ece4Schristos                 if (loadedSize < toLoad) { notDone = 0; break; }   /* not enough input, wait for more */
3489*3117ece4Schristos                 {
3490*3117ece4Schristos                     size_t decodedSize = ZSTD_decompressContinue(zbc->zc,
3491*3117ece4Schristos                         zbc->outBuff + zbc->outStart, zbc->outBuffSize - zbc->outStart,
3492*3117ece4Schristos                         zbc->inBuff, neededInSize);
3493*3117ece4Schristos                     if (ZSTD_isError(decodedSize)) return decodedSize;
3494*3117ece4Schristos                     zbc->inPos = 0;   /* input is consumed */
3495*3117ece4Schristos                     if (!decodedSize) { zbc->stage = ZBUFFds_read; break; }   /* this was just a header */
3496*3117ece4Schristos                     zbc->outEnd = zbc->outStart +  decodedSize;
3497*3117ece4Schristos                     zbc->stage = ZBUFFds_flush;
3498*3117ece4Schristos                     /* ZBUFFds_flush follows */
3499*3117ece4Schristos                 }
3500*3117ece4Schristos             }
3501*3117ece4Schristos 	    /* fall-through */
3502*3117ece4Schristos         case ZBUFFds_flush:
3503*3117ece4Schristos             {
3504*3117ece4Schristos                 size_t toFlushSize = zbc->outEnd - zbc->outStart;
3505*3117ece4Schristos                 size_t flushedSize = ZBUFF_limitCopy(op, oend-op, zbc->outBuff + zbc->outStart, toFlushSize);
3506*3117ece4Schristos                 op += flushedSize;
3507*3117ece4Schristos                 zbc->outStart += flushedSize;
3508*3117ece4Schristos                 if (flushedSize == toFlushSize)
3509*3117ece4Schristos                 {
3510*3117ece4Schristos                     zbc->stage = ZBUFFds_read;
3511*3117ece4Schristos                     if (zbc->outStart + BLOCKSIZE > zbc->outBuffSize)
3512*3117ece4Schristos                         zbc->outStart = zbc->outEnd = 0;
3513*3117ece4Schristos                     break;
3514*3117ece4Schristos                 }
3515*3117ece4Schristos                 /* cannot flush everything */
3516*3117ece4Schristos                 notDone = 0;
3517*3117ece4Schristos                 break;
3518*3117ece4Schristos             }
3519*3117ece4Schristos         default: return ERROR(GENERIC);   /* impossible */
3520*3117ece4Schristos         }
3521*3117ece4Schristos     }
3522*3117ece4Schristos 
3523*3117ece4Schristos     *srcSizePtr = ip-istart;
3524*3117ece4Schristos     *maxDstSizePtr = op-ostart;
3525*3117ece4Schristos 
3526*3117ece4Schristos     {
3527*3117ece4Schristos         size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zbc->zc);
3528*3117ece4Schristos         if (nextSrcSizeHint > 3) nextSrcSizeHint+= 3;   /* get the next block header while at it */
3529*3117ece4Schristos         nextSrcSizeHint -= zbc->inPos;   /* already loaded*/
3530*3117ece4Schristos         return nextSrcSizeHint;
3531*3117ece4Schristos     }
3532*3117ece4Schristos }
3533*3117ece4Schristos 
3534*3117ece4Schristos 
3535*3117ece4Schristos /* *************************************
3536*3117ece4Schristos *  Tool functions
3537*3117ece4Schristos ***************************************/
3538*3117ece4Schristos unsigned ZBUFFv04_isError(size_t errorCode) { return ERR_isError(errorCode); }
3539*3117ece4Schristos const char* ZBUFFv04_getErrorName(size_t errorCode) { return ERR_getErrorName(errorCode); }
3540*3117ece4Schristos 
3541*3117ece4Schristos size_t ZBUFFv04_recommendedDInSize(void)  { return BLOCKSIZE + 3; }
3542*3117ece4Schristos size_t ZBUFFv04_recommendedDOutSize(void) { return BLOCKSIZE; }
3543*3117ece4Schristos 
3544*3117ece4Schristos 
3545*3117ece4Schristos 
3546*3117ece4Schristos /*- ========================================================================= -*/
3547*3117ece4Schristos 
3548*3117ece4Schristos /* final wrapping stage */
3549*3117ece4Schristos 
3550*3117ece4Schristos size_t ZSTDv04_decompressDCtx(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
3551*3117ece4Schristos {
3552*3117ece4Schristos     return ZSTD_decompress_usingDict(dctx, dst, maxDstSize, src, srcSize, NULL, 0);
3553*3117ece4Schristos }
3554*3117ece4Schristos 
3555*3117ece4Schristos size_t ZSTDv04_decompress(void* dst, size_t maxDstSize, const void* src, size_t srcSize)
3556*3117ece4Schristos {
3557*3117ece4Schristos #if defined(ZSTD_HEAPMODE) && (ZSTD_HEAPMODE==1)
3558*3117ece4Schristos     size_t regenSize;
3559*3117ece4Schristos     ZSTD_DCtx* dctx = ZSTD_createDCtx();
3560*3117ece4Schristos     if (dctx==NULL) return ERROR(memory_allocation);
3561*3117ece4Schristos     regenSize = ZSTDv04_decompressDCtx(dctx, dst, maxDstSize, src, srcSize);
3562*3117ece4Schristos     ZSTD_freeDCtx(dctx);
3563*3117ece4Schristos     return regenSize;
3564*3117ece4Schristos #else
3565*3117ece4Schristos     ZSTD_DCtx dctx;
3566*3117ece4Schristos     return ZSTDv04_decompressDCtx(&dctx, dst, maxDstSize, src, srcSize);
3567*3117ece4Schristos #endif
3568*3117ece4Schristos }
3569*3117ece4Schristos 
3570*3117ece4Schristos size_t ZSTDv04_resetDCtx(ZSTDv04_Dctx* dctx) { return ZSTD_resetDCtx(dctx); }
3571*3117ece4Schristos 
3572*3117ece4Schristos size_t ZSTDv04_nextSrcSizeToDecompress(ZSTDv04_Dctx* dctx)
3573*3117ece4Schristos {
3574*3117ece4Schristos     return ZSTD_nextSrcSizeToDecompress(dctx);
3575*3117ece4Schristos }
3576*3117ece4Schristos 
3577*3117ece4Schristos size_t ZSTDv04_decompressContinue(ZSTDv04_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize)
3578*3117ece4Schristos {
3579*3117ece4Schristos     return ZSTD_decompressContinue(dctx, dst, maxDstSize, src, srcSize);
3580*3117ece4Schristos }
3581*3117ece4Schristos 
3582*3117ece4Schristos 
3583*3117ece4Schristos 
3584*3117ece4Schristos ZBUFFv04_DCtx* ZBUFFv04_createDCtx(void) { return ZBUFF_createDCtx(); }
3585*3117ece4Schristos size_t ZBUFFv04_freeDCtx(ZBUFFv04_DCtx* dctx) { return ZBUFF_freeDCtx(dctx); }
3586*3117ece4Schristos 
3587*3117ece4Schristos size_t ZBUFFv04_decompressInit(ZBUFFv04_DCtx* dctx) { return ZBUFF_decompressInit(dctx); }
3588*3117ece4Schristos size_t ZBUFFv04_decompressWithDictionary(ZBUFFv04_DCtx* dctx, const void* src, size_t srcSize)
3589*3117ece4Schristos { return ZBUFF_decompressWithDictionary(dctx, src, srcSize); }
3590*3117ece4Schristos 
3591*3117ece4Schristos size_t ZBUFFv04_decompressContinue(ZBUFFv04_DCtx* dctx, void* dst, size_t* maxDstSizePtr, const void* src, size_t* srcSizePtr)
3592*3117ece4Schristos {
3593*3117ece4Schristos     DEBUGLOG(5, "ZBUFFv04_decompressContinue");
3594*3117ece4Schristos     return ZBUFF_decompressContinue(dctx, dst, maxDstSizePtr, src, srcSizePtr);
3595*3117ece4Schristos }
3596*3117ece4Schristos 
3597*3117ece4Schristos ZSTD_DCtx* ZSTDv04_createDCtx(void) { return ZSTD_createDCtx(); }
3598*3117ece4Schristos size_t ZSTDv04_freeDCtx(ZSTD_DCtx* dctx) { return ZSTD_freeDCtx(dctx); }
3599