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- /*
- ** $Id: lzio.c,v 1.31.1.1 2007/12/27 13:02:25 roberto Exp $
- ** a generic input stream interface
- ** See Copyright Notice in lua.h
- */
- #define lzio_c
- #define LUA_CORE
- #define LUAC_CROSS_FILE
- #include "lua.h"
- #include C_HEADER_STRING
- #include "llimits.h"
- #include "lmem.h"
- #include "lstate.h"
- #include "lzio.h"
- int luaZ_fill (ZIO *z) {
- size_t size;
- lua_State *L = z->L;
- const char *buff;
- lua_unlock(L);
- buff = z->reader(L, z->data, &size);
- lua_lock(L);
- if (buff == NULL || size == 0) return EOZ;
- z->n = size - 1;
- z->p = buff;
- return char2int(*(z->p++));
- }
- int luaZ_lookahead (ZIO *z) {
- if (z->n == 0) {
- if (luaZ_fill(z) == EOZ)
- return EOZ;
- else {
- z->n++; /* luaZ_fill removed first byte; put back it */
- z->p--;
- }
- }
- return char2int(*z->p);
- }
- void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader, void *data) {
- z->L = L;
- z->reader = reader;
- z->data = data;
- z->n = z->i = 0;
- z->p = NULL;
- }
- /* --------------------------------------------------------------- read --- */
- size_t luaZ_read (ZIO *z, void *b, size_t n) {
- while (n) {
- size_t m;
- if (luaZ_lookahead(z) == EOZ)
- return n; /* return number of missing bytes */
- m = (n <= z->n) ? n : z->n; /* min. between n and z->n */
- if (b)
- c_memcpy(b, z->p, m);
- z->n -= m;
- z->i += m;
- z->p += m;
- if (b)
- b = (char *)b + m;
- n -= m;
- }
- return 0;
- }
- /* ------------------------------------------------------------------------ */
- char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n) {
- if (n > buff->buffsize) {
- if (n < LUA_MINBUFFER) n = LUA_MINBUFFER;
- luaZ_resizebuffer(L, buff, n);
- }
- return buff->buffer;
- }
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