/* 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

   Permission is granted to anyone to use this software for any purpose,
   including commercial applications, and to alter it and redistribute it
   freely, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must not
      claim that you wrote the original software. If you use this software
      in a product, an acknowledgment in the product documentation would be
      appreciated but is not required.
   2. Altered source versions must be plainly marked as such, and must not be
      misrepresented as being the original software.
   3. This notice may not be removed or altered from any source distribution.
*/

#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;
}