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