/* ioapi.c -- IO base function header for compress/uncompress .zip
   files using zlib + zip or unzip API

   Version 1.00, September 10th, 2003

   Copyright (C) 1998-2003 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 = 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 = 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;
}
