xref: /netbsd-src/external/mit/lua/dist/src/lzio.h (revision f0dad708b37bd6f5048a66ff2d48c1453845f039)
1 /*	$NetBSD: lzio.h,v 1.9 2023/04/16 20:46:17 nikita Exp $	*/
2 
3 /*
4 ** Id: lzio.h
5 ** Buffered streams
6 ** See Copyright Notice in lua.h
7 */
8 
9 
10 #ifndef lzio_h
11 #define lzio_h
12 
13 #include "lua.h"
14 
15 #include "lmem.h"
16 
17 
18 #define EOZ	(-1)			/* end of stream */
19 
20 typedef struct Zio ZIO;
21 
22 #define zgetc(z)  (((z)->n--)>0 ?  cast_uchar(*(z)->p++) : luaZ_fill(z))
23 
24 
25 typedef struct Mbuffer {
26   char *buffer;
27   size_t n;
28   size_t buffsize;
29 } Mbuffer;
30 
31 #define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)
32 
33 #define luaZ_buffer(buff)	((buff)->buffer)
34 #define luaZ_sizebuffer(buff)	((buff)->buffsize)
35 #define luaZ_bufflen(buff)	((buff)->n)
36 
37 #define luaZ_buffremove(buff,i)	((buff)->n -= (i))
38 #define luaZ_resetbuffer(buff) ((buff)->n = 0)
39 
40 
41 #define luaZ_resizebuffer(L, buff, size) \
42 	((buff)->buffer = luaM_reallocvchar(L, (buff)->buffer, \
43 				(buff)->buffsize, size), \
44 	(buff)->buffsize = size)
45 
46 #define luaZ_freebuffer(L, buff)	luaZ_resizebuffer(L, buff, 0)
47 
48 
49 LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
50                                         void *data);
51 LUAI_FUNC size_t luaZ_read (ZIO* z, void *b, size_t n);	/* read next n bytes */
52 
53 
54 
55 /* --------- Private Part ------------------ */
56 
57 struct Zio {
58   size_t n;			/* bytes still unread */
59   const char *p;		/* current position in buffer */
60   lua_Reader reader;		/* reader function */
61   void *data;			/* additional data */
62   lua_State *L;			/* Lua state (for reader) */
63 };
64 
65 
66 LUAI_FUNC int luaZ_fill (ZIO *z);
67 
68 #endif
69