text: /*
  ** $Id: lzio.h,v 1.21.1.1 2007/12/27 13:02:25 roberto Exp $
  ** Buffered streams
  ** See Copyright Notice in lua.h
  */
  
  
  #ifndef lzio_h
  #define lzio_h
  
  #include "lua.h"
  
  #include "lmem.h"
  
  
  #define EOZ	(-1)			/* end of stream */
  
  typedef struct Zio ZIO;
  
  #define char2int(c)	cast(int, cast(unsigned char, (c)))
  
  #define zgetc(z)  (((z)->n--)>0 ?  char2int(*(z)->p++) : luaZ_fill(z))
  
  typedef struct Mbuffer {
    char *buffer;
    size_t n;
    size_t buffsize;
  } Mbuffer;
  
  #define luaZ_initbuffer(L, buff) ((buff)->buffer = NULL, (buff)->buffsize = 0)
  
  #define luaZ_buffer(buff)	((buff)->buffer)
  #define luaZ_sizebuffer(buff)	((buff)->buffsize)
  #define luaZ_bufflen(buff)	((buff)->n)
  
  #define luaZ_resetbuffer(buff) ((buff)->n = 0)
  
  
  #define luaZ_resizebuffer(L, buff, size) \
  	(luaM_reallocvector(L, (buff)->buffer, (buff)->buffsize, size, char), \
  	(buff)->buffsize = size)
  
  #define luaZ_freebuffer(L, buff)	luaZ_resizebuffer(L, buff, 0)
  
  
  LUAI_FUNC char *luaZ_openspace (lua_State *L, Mbuffer *buff, size_t n);
  LUAI_FUNC void luaZ_init (lua_State *L, ZIO *z, lua_Reader reader,
                                          void *data);
  LUAI_FUNC size_t luaZ_read (ZIO* z, void* b, size_t n);	/* read next n bytes */
  LUAI_FUNC int luaZ_lookahead (ZIO *z);
  
  
  
  /* --------- Private Part ------------------ */
  
  struct Zio {
    size_t n;			/* bytes still unread */
    const char *p;		/* current position in buffer */
    lua_Reader reader;
    void* data;			/* additional data */
    lua_State *L;			/* Lua state (for reader) */
  };
  
  
  LUAI_FUNC int luaZ_fill (ZIO *z);
  
  
  #endif
  