text: /* ioapi.c -- IO base function header for compress/uncompress .zip
     files using zlib + zip or unzip API
  
     Version 1.01e, February 12th, 2005
  
     Copyright (C) 1998-2005 Gilles Vollant
  */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  
  #include "zlib.h"
  #include "ioapi.h"
  
  
  
  /* I've found an old Unix (a SunOS 4.1.3_U1) without all SEEK_* defined.... */
  
  #ifndef SEEK_CUR
  #define SEEK_CUR    1
  #endif
  
  #ifndef SEEK_END
  #define SEEK_END    2
  #endif
  
  #ifndef SEEK_SET
  #define SEEK_SET    0
  #endif
  
  voidpf ZCALLBACK fopen_file_func OF((
     voidpf opaque,
     const char* filename,
     int mode));
  
  uLong ZCALLBACK fread_file_func OF((
     voidpf opaque,
     voidpf stream,
     void* buf,
     uLong size));
  
  uLong ZCALLBACK fwrite_file_func OF((
     voidpf opaque,
     voidpf stream,
     const void* buf,
     uLong size));
  
  long ZCALLBACK ftell_file_func OF((
     voidpf opaque,
     voidpf stream));
  
  long ZCALLBACK fseek_file_func OF((
     voidpf opaque,
     voidpf stream,
     uLong offset,
     int origin));
  
  int ZCALLBACK fclose_file_func OF((
     voidpf opaque,
     voidpf stream));
  
  int ZCALLBACK ferror_file_func OF((
     voidpf opaque,
     voidpf stream));
  
  
  voidpf ZCALLBACK fopen_file_func (opaque, filename, mode)
     voidpf opaque;
     const char* filename;
     int mode;
  {
      FILE* file = NULL;
      const char* mode_fopen = NULL;
      if ((mode & ZLIB_FILEFUNC_MODE_READWRITEFILTER)==ZLIB_FILEFUNC_MODE_READ)
          mode_fopen = "rb";
      else
      if (mode & ZLIB_FILEFUNC_MODE_EXISTING)
          mode_fopen = "r+b";
      else
      if (mode & ZLIB_FILEFUNC_MODE_CREATE)
          mode_fopen = "wb";
  
      if ((filename!=NULL) && (mode_fopen != NULL))
          file = fopen(filename, mode_fopen);
      return file;
  }
  
  
  uLong ZCALLBACK fread_file_func (opaque, stream, buf, size)
     voidpf opaque;
     voidpf stream;
     void* buf;
     uLong size;
  {
      uLong ret;
      ret = (uLong)fread(buf, 1, (size_t)size, (FILE *)stream);
      return ret;
  }
  
  
  uLong ZCALLBACK fwrite_file_func (opaque, stream, buf, size)
     voidpf opaque;
     voidpf stream;
     const void* buf;
     uLong size;
  {
      uLong ret;
      ret = (uLong)fwrite(buf, 1, (size_t)size, (FILE *)stream);
      return ret;
  }
  
  long ZCALLBACK ftell_file_func (opaque, stream)
     voidpf opaque;
     voidpf stream;
  {
      long ret;
      ret = ftell((FILE *)stream);
      return ret;
  }
  
  long ZCALLBACK fseek_file_func (opaque, stream, offset, origin)
     voidpf opaque;
     voidpf stream;
     uLong offset;
     int origin;
  {
      int fseek_origin=0;
      long ret;
      switch (origin)
      {
      case ZLIB_FILEFUNC_SEEK_CUR :
          fseek_origin = SEEK_CUR;
          break;
      case ZLIB_FILEFUNC_SEEK_END :
          fseek_origin = SEEK_END;
          break;
      case ZLIB_FILEFUNC_SEEK_SET :
          fseek_origin = SEEK_SET;
          break;
      default: return -1;
      }
      ret = 0;
      fseek((FILE *)stream, offset, fseek_origin);
      return ret;
  }
  
  int ZCALLBACK fclose_file_func (opaque, stream)
     voidpf opaque;
     voidpf stream;
  {
      int ret;
      ret = fclose((FILE *)stream);
      return ret;
  }
  
  int ZCALLBACK ferror_file_func (opaque, stream)
     voidpf opaque;
     voidpf stream;
  {
      int ret;
      ret = ferror((FILE *)stream);
      return ret;
  }
  
  void fill_fopen_filefunc (pzlib_filefunc_def)
    zlib_filefunc_def* pzlib_filefunc_def;
  {
      pzlib_filefunc_def->zopen_file = fopen_file_func;
      pzlib_filefunc_def->zread_file = fread_file_func;
      pzlib_filefunc_def->zwrite_file = fwrite_file_func;
      pzlib_filefunc_def->ztell_file = ftell_file_func;
      pzlib_filefunc_def->zseek_file = fseek_file_func;
      pzlib_filefunc_def->zclose_file = fclose_file_func;
      pzlib_filefunc_def->zerror_file = ferror_file_func;
      pzlib_filefunc_def->opaque = NULL;
  }
  