xref: /netbsd-src/external/bsd/liblzf/dist/lzf.c (revision e6ea0ca4b63c68aa4d6153608fa0eb4fc2f96f72)
1 /*
2  * Copyright (c) 2006      Stefan Traby <stefan@hello-penguin.com>
3  *
4  * Redistribution and use in source and binary forms, with or without modifica-
5  * tion, are permitted provided that the following conditions are met:
6  *
7  *   1.  Redistributions of source code must retain the above copyright notice,
8  *       this list of conditions and the following disclaimer.
9  *
10  *   2.  Redistributions in binary form must reproduce the above copyright
11  *       notice, this list of conditions and the following disclaimer in the
12  *       documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
15  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16  * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
17  * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
18  * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
20  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
22  * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
23  * OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  * Alternatively, the contents of this file may be used under the terms of
26  * the GNU General Public License ("GPL") version 2 or any later version,
27  * in which case the provisions of the GPL are applicable instead of
28  * the above. If you wish to allow the use of your version of this file
29  * only under the terms of the GPL and not to allow others to use your
30  * version of this file under the BSD license, indicate your decision
31  * by deleting the provisions above and replace them with the notice
32  * and other provisions required by the GPL. If you do not delete the
33  * provisions above, a recipient may use your version of this file under
34  * either the BSD or the GPL.
35  */
36 
37 #include <stdio.h>
38 #include <string.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 #include <fcntl.h>
44 #include <errno.h>
45 #include <limits.h>
46 #include "lzf.h"
47 
48 #ifdef HAVE_GETOPT_H
49 # include <getopt.h>
50 #endif
51 
52 #define BLOCKSIZE (1024 * 64 - 1)
53 #define MAX_BLOCKSIZE BLOCKSIZE
54 
55 static off_t nr_read, nr_written;
56 
57 static const char *imagename;
58 static enum { compress, uncompress, lzfcat } mode = compress;
59 static int verbose = 0;
60 static int force = 0;
61 static long blocksize = BLOCKSIZE;
62 
63 #ifdef HAVE_GETOPT_LONG
64 
65   struct option longopts[] = {
66     {"compress", 0, 0, 'c'},
67     {"decompress", 0, 0, 'd'},
68     {"uncompress", 0, 0, 'd'},
69     {"force", 0, 0, 'f'},
70     {"help", 0, 0, 'h'},
71     {"verbose", 0, 0, 'v'},
72     {"blocksize", 1, 0, 'b'},
73     {0, 0, 0, 0}
74   };
75 
76   static const char *opt =
77     "-c --compress    compress\n"
78     "-d --decompress  decompress\n"
79     "-f --force       force overwrite of output file\n"
80     "-h --help        give this help\n" "-v --verbose     verbose mode\n" "-b # --blocksize # set blocksize\n" "\n";
81 
82 #else
83 
84   static const char *opt =
85     "-c   compress\n"
86     "-d   decompress\n"
87     "-f   force overwrite of output file\n"
88     "-h   give this help\n"
89     "-v   verbose mode\n"
90     "-b # set blocksize\n"
91     "\n";
92 
93 #endif
94 
95 static void
usage(int rc)96 usage (int rc)
97 {
98   fprintf (stderr, "\n"
99            "lzf, a very lightweight compression/decompression utility written by Stefan Traby.\n"
100            "uses liblzf written by Marc Lehmann <schmorp@schmorp.de> You can find more info at\n"
101            "http://liblzf.plan9.de/\n"
102            "\n"
103            "usage: lzf [-dufhvb] [file ...]\n"
104            "       unlzf [file ...]\n"
105            "       lzfcat [file ...]\n"
106            "\n%s",
107            opt);
108 
109   exit (rc);
110 }
111 
112 static inline ssize_t
rread(int fd,void * buf,size_t len)113 rread (int fd, void *buf, size_t len)
114 {
115   ssize_t rc = 0, offset = 0;
116   char *p = buf;
117 
118   while (len && (rc = read (fd, &p[offset], len)) > 0)
119     {
120       offset += rc;
121       len -= rc;
122     }
123 
124   nr_read += offset;
125 
126   if (rc < 0)
127     return rc;
128 
129   return offset;
130 }
131 
132 /* returns 0 if all written else -1 */
133 static inline ssize_t
wwrite(int fd,void * buf,size_t len)134 wwrite (int fd, void *buf, size_t len)
135 {
136   ssize_t rc;
137   char *b = buf;
138   size_t l = len;
139 
140   while (l)
141     {
142       rc = write (fd, b, l);
143       if (rc < 0)
144         {
145           fprintf (stderr, "%s: write error: ", imagename);
146           perror ("");
147           return -1;
148         }
149 
150       l -= rc;
151       b += rc;
152     }
153 
154   nr_written += len;
155   return 0;
156 }
157 
158 /*
159  * Anatomy: an lzf file consists of any number of blocks in the following format:
160  *
161  * \x00   EOF (optional)
162  * "ZV\0" 2-byte-usize <uncompressed data>
163  * "ZV\1" 2-byte-csize 2-byte-usize <compressed data>
164  * "ZV\2" 4-byte-crc32-0xdebb20e3 (NYI)
165  */
166 
167 
168 #define TYPE0_HDR_SIZE 5
169 #define TYPE1_HDR_SIZE 7
170 #define MAX_HDR_SIZE 7
171 #define MIN_HDR_SIZE 5
172 
173 static int
compress_fd(int from,int to)174 compress_fd (int from, int to)
175 {
176   ssize_t us, cs, len;
177   u8 buf1[MAX_BLOCKSIZE + MAX_HDR_SIZE + 16];
178   u8 buf2[MAX_BLOCKSIZE + MAX_HDR_SIZE + 16];
179   u8 *header;
180 
181   nr_read = nr_written = 0;
182   while ((us = rread (from, &buf1[MAX_HDR_SIZE], blocksize)) > 0)
183     {
184       cs = lzf_compress (&buf1[MAX_HDR_SIZE], us, &buf2[MAX_HDR_SIZE], us > 4 ? us - 4 : us);
185       if (cs)
186         {
187           header = &buf2[MAX_HDR_SIZE - TYPE1_HDR_SIZE];
188           header[0] = 'Z';
189           header[1] = 'V';
190           header[2] = 1;
191           header[3] = cs >> 8;
192           header[4] = cs & 0xff;
193           header[5] = us >> 8;
194           header[6] = us & 0xff;
195           len = cs + TYPE1_HDR_SIZE;
196         }
197       else
198         {                       // write uncompressed
199           header = &buf1[MAX_HDR_SIZE - TYPE0_HDR_SIZE];
200           header[0] = 'Z';
201           header[1] = 'V';
202           header[2] = 0;
203           header[3] = us >> 8;
204           header[4] = us & 0xff;
205           len = us + TYPE0_HDR_SIZE;
206         }
207 
208       if (wwrite (to, header, len) == -1)
209         return -1;
210     }
211 
212   return 0;
213 }
214 
215 static int
uncompress_fd(int from,int to)216 uncompress_fd (int from, int to)
217 {
218   u8 header[MAX_HDR_SIZE];
219   u8 buf1[MAX_BLOCKSIZE + MAX_HDR_SIZE + 16];
220   u8 buf2[MAX_BLOCKSIZE + MAX_HDR_SIZE + 16];
221   u8 *p;
222   int l, rd;
223   ssize_t rc, cs, us, bytes, over = 0;
224 
225   nr_read = nr_written = 0;
226   while (1)
227     {
228       rc = rread (from, header + over, MAX_HDR_SIZE - over);
229       if (rc < 0)
230         {
231           fprintf (stderr, "%s: read error: ", imagename);
232           perror ("");
233           return -1;
234         }
235 
236       rc += over;
237       over = 0;
238       if (!rc || header[0] == 0)
239         return 0;
240 
241       if (rc < MIN_HDR_SIZE || header[0] != 'Z' || header[1] != 'V')
242         {
243           fprintf (stderr, "%s: invalid data stream - magic not found or short header\n", imagename);
244           return -1;
245         }
246 
247       switch (header[2])
248         {
249           case 0:
250             cs = -1;
251             us = (header[3] << 8) | header[4];
252             p = &header[TYPE0_HDR_SIZE];
253             break;
254           case 1:
255             if (rc < TYPE1_HDR_SIZE)
256               {
257                 goto short_read;
258               }
259             cs = (header[3] << 8) | header[4];
260             us = (header[5] << 8) | header[6];
261             p = &header[TYPE1_HDR_SIZE];
262             break;
263           default:
264             fprintf (stderr, "%s: unknown blocktype\n", imagename);
265             return -1;
266         }
267 
268       bytes = cs == -1 ? us : cs;
269       l = &header[rc] - p;
270 
271       if (l > 0)
272         memcpy (buf1, p, l);
273 
274       if (l > bytes)
275         {
276           over = l - bytes;
277           memmove (header, &p[bytes], over);
278         }
279 
280       p = &buf1[l];
281       rd = bytes - l;
282       if (rd > 0)
283         if ((rc = rread (from, p, rd)) != rd)
284           goto short_read;
285 
286       if (cs == -1)
287         {
288           if (wwrite (to, buf1, us))
289             return -1;
290         }
291       else
292         {
293           if (lzf_decompress (buf1, cs, buf2, us) != us)
294             {
295               fprintf (stderr, "%s: decompress: invalid stream - data corrupted\n", imagename);
296               return -1;
297             }
298 
299           if (wwrite (to, buf2, us))
300             return -1;
301         }
302     }
303 
304   return 0;
305 
306 short_read:
307   fprintf (stderr, "%s: short data\n", imagename);
308   return -1;
309 }
310 
311 static int
open_out(const char * name)312 open_out (const char *name)
313 {
314   int fd;
315   int m = O_EXCL;
316 
317   if (force)
318     m = 0;
319 
320   fd = open (name, O_CREAT | O_WRONLY | O_TRUNC | m, 600);
321 #if defined(__MINGW32__)
322   _setmode(fd, _O_BINARY);
323 #endif
324   return fd;
325 }
326 
327 static int
compose_name(const char * fname,char * oname)328 compose_name (const char *fname, char *oname)
329 {
330   char *p;
331 
332   if (mode == compress)
333     {
334       if (strlen (fname) > PATH_MAX - 4)
335         {
336           fprintf (stderr, "%s: %s.lzf: name too long", imagename, fname);
337           return -1;
338         }
339 
340       strcpy (oname, fname);
341       strcat (oname, ".lzf");
342     }
343   else
344     {
345       if (strlen (fname) > PATH_MAX)
346         {
347           fprintf (stderr, "%s: %s: name too long\n", imagename, fname);
348           return -1;
349         }
350 
351       strcpy (oname, fname);
352       p = &oname[strlen (oname)] - 4;
353       if (p < oname || strcmp (p, ".lzf"))
354         {
355           fprintf (stderr, "%s: %s: unknown suffix\n", imagename, fname);
356           return -1;
357         }
358 
359       *p = 0;
360     }
361 
362   return 0;
363 }
364 
365 static int
run_file(const char * fname)366 run_file (const char *fname)
367 {
368   int fd, fd2;
369   int rc;
370   struct stat mystat;
371   char oname[PATH_MAX + 1];
372 
373   if (mode != lzfcat)
374     if (compose_name (fname, oname))
375       return -1;
376 
377 #if !defined(__MINGW32__)
378   rc = lstat (fname, &mystat);
379 #else
380   rc = stat (fname, &mystat);
381 #endif
382   fd = open (fname, O_RDONLY);
383 #if defined(__MINGW32__)
384   _setmode(fd, _O_BINARY);
385 #endif
386   if (rc || fd == -1)
387     {
388       fprintf (stderr, "%s: %s: ", imagename, fname);
389       perror ("");
390       return -1;
391     }
392 
393   if (!S_ISREG (mystat.st_mode))
394     {
395       fprintf (stderr, "%s: %s: not a regular file.\n", imagename, fname);
396       close (fd);
397       return -1;
398     }
399 
400   if (mode == lzfcat)
401     {
402       rc = uncompress_fd (fd, 1);
403       close (fd);
404       return rc;
405     }
406 
407   fd2 = open_out (oname);
408   if (fd2 == -1)
409     {
410       fprintf (stderr, "%s: %s: ", imagename, oname);
411       perror ("");
412       close (fd);
413       return -1;
414     }
415 
416   if (mode == compress)
417     {
418       rc = compress_fd (fd, fd2);
419       if (!rc && verbose)
420         fprintf (stderr, "%s:  %5.1f%% -- replaced with %s\n",
421                  fname, nr_read == 0 ? 0 : 100.0 - nr_written / ((double) nr_read / 100.0), oname);
422     }
423   else
424     {
425       rc = uncompress_fd (fd, fd2);
426       if (!rc && verbose)
427         fprintf (stderr, "%s:  %5.1f%% -- replaced with %s\n",
428                  fname, nr_written == 0 ? 0 : 100.0 - nr_read / ((double) nr_written / 100.0), oname);
429     }
430 
431 #if !defined(__MINGW32__)
432   fchmod (fd2, mystat.st_mode);
433 #else
434   chmod (oname, mystat.st_mode);
435 #endif
436   close (fd);
437   close (fd2);
438 
439   if (!rc)
440     unlink (fname);
441 
442   return rc;
443 }
444 
445 int
main(int argc,char * argv[])446 main (int argc, char *argv[])
447 {
448   char *p = argv[0];
449   int optc;
450   int rc = 0;
451 
452   errno = 0;
453   p = getenv ("LZF_BLOCKSIZE");
454   if (p)
455     {
456       blocksize = strtoul (p, 0, 0);
457       if (errno || !blocksize || blocksize > MAX_BLOCKSIZE)
458         blocksize = BLOCKSIZE;
459     }
460 
461   p = strrchr (argv[0], '/');
462   imagename = p ? ++p : argv[0];
463 
464   if (!strncmp (imagename, "un", 2) || !strncmp (imagename, "de", 2))
465     mode = uncompress;
466 
467   if (strstr (imagename, "cat"))
468     mode = lzfcat;
469 
470 #ifdef HAVE_GETOPT_LONG
471   while ((optc = getopt_long (argc, argv, "cdfhvb:", longopts, 0)) != -1)
472 #else
473   while ((optc = getopt (argc, argv, "cdfhvb:")) != -1)
474 #endif
475     {
476       switch (optc)
477         {
478           case 'c':
479             mode = compress;
480             break;
481           case 'd':
482             mode = uncompress;
483             break;
484           case 'f':
485             force = 1;
486             break;
487           case 'h':
488             usage (0);
489             break;
490           case 'v':
491             verbose = 1;
492             break;
493           case 'b':
494             errno = 0;
495             blocksize = strtoul (optarg, 0, 0);
496             if (errno || !blocksize || blocksize > MAX_BLOCKSIZE)
497               blocksize = BLOCKSIZE;
498             break;
499           default:
500             usage (1);
501             break;
502         }
503     }
504 
505   if (optind == argc)
506     {                           // stdin stdout
507       if (!force)
508         {
509           if ((mode == uncompress || mode == lzfcat) && isatty (0))
510             {
511               fprintf (stderr, "%s: compressed data not read from a terminal. Use -f to force decompression.\n", imagename);
512               exit (1);
513             }
514           if (mode == compress && isatty (1))
515             {
516               fprintf (stderr, "%s: compressed data not written to a terminal. Use -f to force compression.\n", imagename);
517               exit (1);
518             }
519         }
520 
521       if (mode == compress)
522         rc = compress_fd (0, 1);
523       else
524         rc = uncompress_fd (0, 1);
525 
526       exit (rc ? 1 : 0);
527     }
528 
529   while (optind < argc)
530     rc |= run_file (argv[optind++]);
531 
532   exit (rc ? 1 : 0);
533 }
534 
535