diff options
Diffstat (limited to 'lzio.c')
-rw-r--r-- | lzio.c | 76 |
1 files changed, 76 insertions, 0 deletions
@@ -0,0 +1,76 @@ | |||
1 | /* | ||
2 | ** $Id: lzio.c,v 1.35 2012/05/14 13:34:18 roberto Exp $ | ||
3 | ** Buffered streams | ||
4 | ** See Copyright Notice in lua.h | ||
5 | */ | ||
6 | |||
7 | |||
8 | #include <string.h> | ||
9 | |||
10 | #define lzio_c | ||
11 | #define LUA_CORE | ||
12 | |||
13 | #include "lua.h" | ||
14 | |||
15 | #include "llimits.h" | ||
16 | #include "lmem.h" | ||
17 | #include "lstate.h" | ||
18 | #include "lzio.h" | ||
19 | |||
20 | |||
21 | int luaZ_fill (ZIO *z) { | ||
22 | size_t size; | ||
23 | lua_State *L = z->L; | ||
24 | const char *buff; | ||
25 | lua_unlock(L); | ||
26 | buff = z->reader(L, z->data, &size); | ||
27 | lua_lock(L); | ||
28 | if (buff == NULL || size == 0) | ||
29 | return EOZ; | ||
30 | z->n = size - 1; /* discount char being returned */ | ||
31 | z->p = buff; | ||
32 | return cast_uchar(*(z->p++)); | ||
33 | } | ||
34 | |||
35 | |||
36 | void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) { | ||
37 | z->L = L; | ||
38 | z->reader = reader; | ||
39 | z->data = data; | ||
40 | z->n = 0; | ||
41 | z->p = NULL; | ||
42 | } | ||
43 | |||
44 | |||
45 | /* --------------------------------------------------------------- read --- */ | ||
46 | size_t luaZ_read (ZIO *z, void *b, size_t n) { | ||
47 | while (n) { | ||
48 | size_t m; | ||
49 | if (z->n == 0) { /* no bytes in buffer? */ | ||
50 | if (luaZ_fill(z) == EOZ) /* try to read more */ | ||
51 | return n; /* no more input; return number of missing bytes */ | ||
52 | else { | ||
53 | z->n++; /* luaZ_fill consumed first byte; put it back */ | ||
54 | z->p--; | ||
55 | } | ||
56 | } | ||
57 | m = (n <= z->n) ? n : z->n; /* min. between n and z->n */ | ||
58 | memcpy(b, z->p, m); | ||
59 | z->n -= m; | ||
60 | z->p += m; | ||
61 | b = (char *)b + m; | ||
62 | n -= m; | ||
63 | } | ||
64 | return 0; | ||
65 | } | ||
66 | |||
67 | /* ------------------------------------------------------------------------ */ | ||
68 | char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n) { | ||
69 | if (n > buff->buffsize) { | ||
70 | if (n < LUA_MINBUFFER) n = LUA_MINBUFFER; | ||
71 | luaZ_resizebuffer(L, buff, n); | ||
72 | } | ||
73 | return buff->buffer; | ||
74 | } | ||
75 | |||
76 | |||