1 /*
2 ** $Id: lzio.h,v 1.21.1.1 2007/12/27 13:02:25 roberto Exp $
3 ** Buffered streams
4 ** See Copyright Notice in lua.h
5 */
6 
7 
8 #ifndef lzio_h
9 #define lzio_h
10 
11 #include "lua.h"
12 
13 #include "lmem.h"
14 
15 
16 #define EOZ	(-1)			/* end of stream */
17 
18 typedef struct Zio ZIO;
19 
20 #define char2int(c)	cast(int, cast(unsigned char, (c)))
21 
22 #define zgetc(z)  (((z)->n--)>0 ?  char2int(*(z)->p++) : luaZ_fill(z))
23 
24 typedef struct Mbuffer {
25   char *buffer;
26   size_t n;
27   size_t buffsize;
28 } Mbuffer;
29 
30 #define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)
31 
32 #define luaZ_buffer(buff)	((buff)->buffer)
33 #define luaZ_sizebuffer(buff)	((buff)->buffsize)
34 #define luaZ_bufflen(buff)	((buff)->n)
35 
36 #define luaZ_resetbuffer(buff) ((buff)->n = 0)
37 
38 
39 #define luaZ_resizebuffer(L, buff, size) \
40 	(luaM_reallocvector(L, (buff)->buffer, (buff)->buffsize, size, char), \
41 	(buff)->buffsize = size)
42 
43 #define luaZ_freebuffer(L, buff)	luaZ_resizebuffer(L, buff, 0)
44 
45 
46 LUAI_FUNC char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n);
47 LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
48                                         void *data);
49 LUAI_FUNC size_t luaZ_read (ZIO* z, void* b, size_t n);	/* read next n bytes */
50 LUAI_FUNC int luaZ_lookahead (ZIO *z);
51 
52 
53 
54 /* --------- Private Part ------------------ */
55 
56 struct Zio {
57   size_t n;			/* bytes still unread */
58   const char *p;		/* current position in buffer */
59   lua_Reader reader;
60   void* data;			/* additional data */
61   lua_State *L;			/* Lua state (for reader) */
62 };
63 
64 
65 LUAI_FUNC int luaZ_fill (ZIO *z);
66 
67 #endif
68