// VisualBoyAdvance - Nintendo Gameboy/GameboyAdvance (TM) emulator.
// Copyright (C) 1999-2003 Forgotten
// Copyright (C) 2004 Forgotten and the VBA development team

// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2, or(at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software Foundation,
// Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

#include "sdfileio.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <zlib.h>

extern "C"
  {
#include <png.h>
  }

#if 0
#include "unrarlib.h"
#endif

#include "System.h"
#include "NLS.h"
#include "Util.h"
#include "Flash.h"
#include "GBA.h"
#include "Globals.h"
#include "RTC.h"
#include "Port.h"

extern "C"
  {
#include "memgzio.h"
  }

#ifndef _MSC_VER
#define _stricmp strcasecmp
#endif // ! _MSC_VER

static int (*utilGzWriteFunc)(gzFile, const voidp, unsigned int) = NULL;
static int (*utilGzReadFunc)(gzFile, voidp, unsigned int) = NULL;
static int (*utilGzCloseFunc)(gzFile) = NULL;

bool utilWritePNGFile(const char *fileName, int w, int h, u8 *pix)
{
#if 0
  u8 writeBuffer[512 * 3];

  FILE* fp = gen_fopen(fileName,"wb");

  if(!fp)
    {
      systemMessage(MSG_ERROR_CREATING_FILE, N_("Error creating file %s"), fileName);
      return false;
    }

  png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
                        NULL,
                        NULL,
                        NULL);
  if(!png_ptr)
    {
      gen_fclose(fp);
      return false;
    }

  png_infop info_ptr = png_create_info_struct(png_ptr);

  if(!info_ptr)
    {
      png_destroy_write_struct(&png_ptr,NULL);
      gen_fclose(fp);
      return false;
    }

  if(setjmp(png_ptr->jmpbuf))
    {
      png_destroy_write_struct(&png_ptr,NULL);
      gen_fclose(fp);
      return false;
    }

  png_init_io(png_ptr,fp);

  png_set_IHDR(png_ptr,
               info_ptr,
               w,
               h,
               8,
               PNG_COLOR_TYPE_RGB,
               PNG_INTERLACE_NONE,
               PNG_COMPRESSION_TYPE_DEFAULT,
               PNG_FILTER_TYPE_DEFAULT);

  png_write_info(png_ptr,info_ptr);

  u8 *b = writeBuffer;

  int sizeX = w;
  int sizeY = h;

  switch(systemColorDepth)
    {
    case 16:
    {
      u16 *p = (u16 *)(pix+(w+2)*2); // skip first black line
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u16 v = *p++;

              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemBlueShift) & 0x01f) << 3; // B
            }
          p++; // skip black pixel for filters
          p++; // skip black pixel for filters
          png_write_row(png_ptr,writeBuffer);

          b = writeBuffer;
        }
    }
    break;
    case 24:
    {
      u8 *pixU8 = (u8 *)pix;
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              if(systemRedShift < systemBlueShift)
                {
                  *b++ = *pixU8++; // R
                  *b++ = *pixU8++; // G
                  *b++ = *pixU8++; // B
                }
              else
                {
                  int blue = *pixU8++;
                  int green = *pixU8++;
                  int red = *pixU8++;

                  *b++ = red;
                  *b++ = green;
                  *b++ = blue;
                }
            }
          png_write_row(png_ptr,writeBuffer);

          b = writeBuffer;
        }
    }
    break;
    case 32:
    {
      u32 *pixU32 = (u32 *)(pix+4*(w+1));
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u32 v = *pixU32++;

              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemBlueShift) & 0x001f) << 3; // B
            }
          pixU32++;

          png_write_row(png_ptr,writeBuffer);

          b = writeBuffer;
        }
    }
    break;
    }

  png_write_end(png_ptr, info_ptr);

  png_destroy_write_struct(&png_ptr, &info_ptr);

  gen_fclose(fp);

#endif
  return true;
}

void utilPutDword(u8 *p, u32 value)
{
  *p++ = value & 255;
  *p++ = (value >> 8) & 255;
  *p++ = (value >> 16) & 255;
  *p = (value >> 24) & 255;
}

void utilPutWord(u8 *p, u16 value)
{
  *p++ = value & 255;
  *p = (value >> 8) & 255;
}

void utilWriteBMP(char *buf, int w, int h, u8 *pix)
{
  u8 *b = (u8 *)buf;

  int sizeX = w;
  int sizeY = h;

  switch(systemColorDepth)
    {
    case 16:
    {
      u16 *p = (u16 *)(pix+(w+2)*(h)*2); // skip first black line
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u16 v = *p++;

              *b++ = ((v >> systemBlueShift) & 0x01f) << 3; // B
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
            }
          p++; // skip black pixel for filters
          p++; // skip black pixel for filters
          p -= 2*(w+2);
        }
    }
    break;
    case 24:
    {
      u8 *pixU8 = (u8 *)pix+3*w*(h-1);
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              if(systemRedShift > systemBlueShift)
                {
                  *b++ = *pixU8++; // B
                  *b++ = *pixU8++; // G
                  *b++ = *pixU8++; // R
                }
              else
                {
                  int red = *pixU8++;
                  int green = *pixU8++;
                  int blue = *pixU8++;

                  *b++ = blue;
                  *b++ = green;
                  *b++ = red;
                }
            }
          pixU8 -= 2*3*w;
        }
    }
    break;
    case 32:
    {
      u32 *pixU32 = (u32 *)(pix+4*(w+1)*(h));
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u32 v = *pixU32++;

              *b++ = ((v >> systemBlueShift) & 0x001f) << 3; // B
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
            }
          pixU32++;
          pixU32 -= 2*(w+1);
        }
    }
    break;
    }
}

bool utilWriteBMPFile(const char *fileName, int w, int h, u8 *pix)
{
  u8 writeBuffer[512 * 3];

  FILE* fp = gen_fopen(fileName,"wb");

  if(!fp)
    {
      systemMessage(MSG_ERROR_CREATING_FILE, N_("Error creating file %s"), fileName);
      return false;
    }

  struct
    {
      u8 ident[2];
      u8 filesize[4];
      u8 reserved[4];
      u8 dataoffset[4];
      u8 headersize[4];
      u8 width[4];
      u8 height[4];
      u8 planes[2];
      u8 bitsperpixel[2];
      u8 compression[4];
      u8 datasize[4];
      u8 hres[4];
      u8 vres[4];
      u8 colors[4];
      u8 importantcolors[4];
      //    u8 pad[2];
    }
  bmpheader;
  memset(&bmpheader, 0, sizeof(bmpheader));

  bmpheader.ident[0] = 'B';
  bmpheader.ident[1] = 'M';

  u32 fsz = sizeof(bmpheader) + w*h*3;
  utilPutDword(bmpheader.filesize, fsz);
  utilPutDword(bmpheader.dataoffset, 0x36);
  utilPutDword(bmpheader.headersize, 0x28);
  utilPutDword(bmpheader.width, w);
  utilPutDword(bmpheader.height, h);
  utilPutDword(bmpheader.planes, 1);
  utilPutDword(bmpheader.bitsperpixel, 24);
  utilPutDword(bmpheader.datasize, 3*w*h);

  gen_fwrite(&bmpheader, 1, sizeof(bmpheader), fp);

  u8 *b = writeBuffer;

  int sizeX = w;
  int sizeY = h;

  switch(systemColorDepth)
    {
    case 16:
    {
      u16 *p = (u16 *)(pix+(w+2)*(h)*2); // skip first black line
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u16 v = *p++;

              *b++ = ((v >> systemBlueShift) & 0x01f) << 3; // B
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
            }
          p++; // skip black pixel for filters
          p++; // skip black pixel for filters
          p -= 2*(w+2);
          gen_fwrite(writeBuffer, 1, 3*w, fp);

          b = writeBuffer;
        }
    }
    break;
    case 24:
    {
      u8 *pixU8 = (u8 *)pix+3*w*(h-1);
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              if(systemRedShift > systemBlueShift)
                {
                  *b++ = *pixU8++; // B
                  *b++ = *pixU8++; // G
                  *b++ = *pixU8++; // R
                }
              else
                {
                  int red = *pixU8++;
                  int green = *pixU8++;
                  int blue = *pixU8++;

                  *b++ = blue;
                  *b++ = green;
                  *b++ = red;
                }
            }
          pixU8 -= 2*3*w;
          gen_fwrite(writeBuffer, 1, 3*w, fp);

          b = writeBuffer;
        }
    }
    break;
    case 32:
    {
      u32 *pixU32 = (u32 *)(pix+4*(w+1)*(h));
      for(int y = 0; y < sizeY; y++)
        {
          for(int x = 0; x < sizeX; x++)
            {
              u32 v = *pixU32++;

              *b++ = ((v >> systemBlueShift) & 0x001f) << 3; // B
              *b++ = ((v >> systemGreenShift) & 0x001f) << 3; // G
              *b++ = ((v >> systemRedShift) & 0x001f) << 3; // R
            }
          pixU32++;
          pixU32 -= 2*(w+1);

          gen_fwrite(writeBuffer, 1, 3*w, fp);

          b = writeBuffer;
        }
    }
    break;
    }

  gen_fclose(fp);

  return true;
}

static int utilReadInt2(FILE* f)
{
  int res = 0;
  int c = gen_fgetc(f);
  if(c == EOF)
    return -1;
  res = c;
  c = gen_fgetc(f);
  if(c == EOF)
    return -1;
  return c + (res<<8);
}

static int utilReadInt3(FILE* f)
{
  int res = 0;
  int c = gen_fgetc(f);
  if(c == EOF)
    return -1;
  res = c;
  c = gen_fgetc(f);
  if(c == EOF)
    return -1;
  res = c + (res<<8);
  c = gen_fgetc(f);
  if(c == EOF)
    return -1;
  return c + (res<<8);
}

void utilApplyIPS(const char *ips, u8 **r, int *s)
{
  // from the IPS spec at http://zerosoft.zophar.net/ips.htm
  FILE* f = gen_fopen(ips, "rb");
  if(!f)
    return;
  u8 *rom = *r;
  int size = *s;
  if(gen_fgetc(f) == 'P' &&
      gen_fgetc(f) == 'A' &&
      gen_fgetc(f) == 'T' &&
      gen_fgetc(f) == 'C' &&
      gen_fgetc(f) == 'H')
    {
      int b;
      int offset;
      int len;
      for(;;)
        {
          // read offset
          offset = utilReadInt3(f);
          // if offset == EOF, end of patch
          if(offset == 0x454f46)
            break;
          // read length
          len = utilReadInt2(f);
          if(!len)
            {
              // len == 0, RLE block
              len = utilReadInt2(f);
              // byte to fill
              int c = gen_fgetc(f);
              if(c == -1)
                break;
              b = (u8)c;
            }
          else
            b= -1;
          // check if we need to reallocate our ROM
          if((offset + len) >= size)
            {
              size *= 2;
              rom = (u8 *)realloc(rom, size);
              *r = rom;
              *s = size;
            }
          if(b == -1)
            {
              // normal block, just read the data
              //if(gen_fread(&rom[offset], 1, len, f) != (size_t)len)
	      if(gen_fread(&rom[offset], 1, len, f) != (int)len)
                break;
            }
          else
            {
              // fill the region with the given byte
              while(len--)
                {
                  rom[offset++] = b;
                }
            }
        }
    }
  // close the file
  gen_fclose(f);
}

extern bool cpuIsMultiBoot;

bool utilIsGBAImage(const char * file)
{
  cpuIsMultiBoot = false;
  if(strlen(file) > 4)
    {
      char * p = strrchr(file,'.');

      if(p != NULL)
        {
          if(_stricmp(p, ".gba") == 0)
            return true;
          if(_stricmp(p, ".agb") == 0)
            return true;
          if(_stricmp(p, ".bin") == 0)
            return true;
          if(_stricmp(p, ".elf") == 0)
            return true;
          if(_stricmp(p, ".mb") == 0)
            {
              cpuIsMultiBoot = true;
              return true;
            }
        }
    }

  return false;
}

bool utilIsGBImage(const char * file)
{
  if(strlen(file) > 4)
    {
      char * p = strrchr(file,'.');

      if(p != NULL)
        {
          if(_stricmp(p, ".gb") == 0)
            return true;
          if(_stricmp(p, ".gbc") == 0)
            return true;
          if(_stricmp(p, ".cgb") == 0)
            return true;
          if(_stricmp(p, ".sgb") == 0)
            return true;
        }
    }

  return false;
}

bool utilIsZipFile(const char *file)
{
  if(strlen(file) > 4)
    {
      char * p = strrchr(file,'.');

      if(p != NULL)
        {
          if(_stricmp(p, ".zip") == 0)
            return true;
        }
    }

  return false;
}

#if 0
bool utilIsRarFile(const char *file)
{
  if(strlen(file) > 4)
    {
      char * p = strrchr(file,'.');

      if(p != NULL)
        {
          if(_stricmp(p, ".rar") == 0)
            return true;
        }
    }

  return false;
}
#endif

bool utilIsGzipFile(const char *file)
{
  if(strlen(file) > 3)
    {
      char * p = strrchr(file,'.');

      if(p != NULL)
        {
          if(_stricmp(p, ".gz") == 0)
            return true;
          if(_stricmp(p, ".z") == 0)
            return true;
        }
    }

  return false;
}

void utilGetBaseName(const char *file, char *buffer)
{
  strcpy(buffer, file);

  if(utilIsGzipFile(file))
    {
      char *p = strrchr(buffer, '.');

      if(p)
        *p = 0;
    }
}

IMAGE_TYPE utilFindType(const char *file)
{
  char buffer[2048];

  if(utilIsZipFile(file))
    {
      unzFile unz = unzOpen(file);

      if(unz == NULL)
        {
          systemMessage(MSG_CANNOT_OPEN_FILE, N_("Cannot open file %s"), file);
          return IMAGE_UNKNOWN;
        }

      int r = unzGoToFirstFile(unz);

      if(r != UNZ_OK)
        {
          unzClose(unz);
          systemMessage(MSG_BAD_ZIP_FILE, N_("Bad ZIP file %s"), file);
          return IMAGE_UNKNOWN;
        }

      IMAGE_TYPE found = IMAGE_UNKNOWN;

      unz_file_info info;

      while(true)
        {
          r = unzGetCurrentFileInfo(unz,
                                    &info,
                                    buffer,
                                    sizeof(buffer),
                                    NULL,
                                    0,
                                    NULL,
                                    0);

          if(r != UNZ_OK)
            {
              unzClose(unz);
              systemMessage(MSG_BAD_ZIP_FILE, N_("Bad ZIP file %s"), file);
              return IMAGE_UNKNOWN;
            }

          if(utilIsGBAImage(buffer))
            {
              found = IMAGE_GBA;
              break;
            }

          if(utilIsGBImage(buffer))
            {
              found = IMAGE_GB;
              break;
            }

          r = unzGoToNextFile(unz);

          if(r != UNZ_OK)
            break;
        }
      unzClose(unz);

      if(found == IMAGE_UNKNOWN)
        {
          systemMessage(MSG_NO_IMAGE_ON_ZIP,
                        N_("No image found on ZIP file %s"), file);
          return found;
        }
      return found;
#if 0
    }
  else if(utilIsRarFile(file))
    {
      IMAGE_TYPE found = IMAGE_UNKNOWN;

      ArchiveList_struct *rarList = NULL;
      if(urarlib_list((void *)file, (ArchiveList_struct *)&rarList))
        {
          ArchiveList_struct *p = rarList;

          while(p)
            {
              if(utilIsGBAImage(p->item.Name))
                {
                  found = IMAGE_GBA;
                  break;
                }

              if(utilIsGBImage(p->item.Name))
                {
                  found = IMAGE_GB;
                  break;
                }
              p = p->next;
            }

          urarlib_freelist(rarList);
        }
      return found;
#endif
    }
  else
    {
      if(utilIsGzipFile(file))
        utilGetBaseName(file, buffer);
      else
        strcpy(buffer, file);

      if(utilIsGBAImage(buffer))
        return IMAGE_GBA;
      if(utilIsGBImage(buffer))
        return IMAGE_GB;
    }
  return IMAGE_UNKNOWN;
}

static int utilGetSize(int size)
{
  int res = 1;
  while(res < size)
    res <<= 1;
  return res;
}

static u8 *utilLoadFromZip(const char *file,
                           bool (*accept)(const char *),
                           u8 *data,
                           int &size)
{
  char buffer[2048];

  unzFile unz = unzOpen(file);

  if(unz == NULL)
    {
      systemMessage(MSG_CANNOT_OPEN_FILE, N_("Cannot open file %s"), file);
      return NULL;
    }
  int r = unzGoToFirstFile(unz);

  if(r != UNZ_OK)
    {
      unzClose(unz);
      systemMessage(MSG_BAD_ZIP_FILE, N_("Bad ZIP file %s"), file);
      return NULL;
    }

  bool found = false;

  unz_file_info info;

  while(true)
    {
      r = unzGetCurrentFileInfo(unz,
                                &info,
                                buffer,
                                sizeof(buffer),
                                NULL,
                                0,
                                NULL,
                                0);

      if(r != UNZ_OK)
        {
          unzClose(unz);
          systemMessage(MSG_BAD_ZIP_FILE, N_("Bad ZIP file %s"), file);
          return NULL;
        }

      if(accept(buffer))
        {
          found = true;
          break;
        }

      r = unzGoToNextFile(unz);

      if(r != UNZ_OK)
        break;
    }

  if(!found)
    {
      unzClose(unz);
      systemMessage(MSG_NO_IMAGE_ON_ZIP,
                    N_("No image found on ZIP file %s"), file);
      return NULL;
    }

  int fileSize = info.uncompressed_size;
  if(size == 0)
    size = fileSize;
  r = unzOpenCurrentFile(unz);

  if(r != UNZ_OK)
    {
      unzClose(unz);
      systemMessage(MSG_ERROR_OPENING_IMAGE, N_("Error opening image %s"), buffer);
      return NULL;
    }

  u8 *image = data;

  if(image == NULL)
    {
      image = (u8 *)malloc(utilGetSize(size));
      if(image == NULL)
        {
          unzCloseCurrentFile(unz);
          unzClose(unz);
          systemMessage(MSG_OUT_OF_MEMORY, N_("Failed to allocate memory for %s"),
                        "data");
          return NULL;
        }
      size = fileSize;
    }
  int read = fileSize <= size ? fileSize : size;
  r = unzReadCurrentFile(unz,
                         image,
                         read);

  unzCloseCurrentFile(unz);
  unzClose(unz);

  if(r != (int)read)
    {
      systemMessage(MSG_ERROR_READING_IMAGE,
                    N_("Error reading image %s"), buffer);
      if(data == NULL)
        free(image);
      return NULL;
    }

  size = fileSize;

  return image;
}

static u8 *utilLoadGzipFile(const char *file,
                            bool (*accept)(const char *),
                            u8 *data,
                            int &size)
{
  FILE* f = gen_fopen(file, "rb");

  if(f == NULL)
    {
      systemMessage(MSG_ERROR_OPENING_IMAGE, N_("Error opening image %s"), file);
      return NULL;
    }

  gen_fseek(f, -4, SEEK_END);
  int fileSize = gen_fgetc(f) | (gen_fgetc(f) << 8) | (gen_fgetc(f) << 16) | (gen_fgetc(f) << 24);
  gen_fclose(f);
  if(size == 0)
    size = fileSize;

  gzFile gz = gzopen(file, "rb");

  if(gz == NULL)
    {
      // should not happen, but who knows?
      systemMessage(MSG_ERROR_OPENING_IMAGE, N_("Error opening image %s"), file);
      return NULL;
    }

  u8 *image = data;

  if(image == NULL)
    {
      image = (u8 *)malloc(utilGetSize(size));
      if(image == NULL)
        {
          systemMessage(MSG_OUT_OF_MEMORY, N_("Failed to allocate memory for %s"),
                        "data");
          gen_fclose(f);
          return NULL;
        }
      size = fileSize;
    }
  int read = fileSize <= size ? fileSize : size;
  int r = gzread(gz, image, read);
  gzclose(gz);

  if(r != (int)read)
    {
      systemMessage(MSG_ERROR_READING_IMAGE,
                    N_("Error reading image %s"), file);
      if(data == NULL)
        free(image);
      return NULL;
    }

  size = fileSize;

  return image;
}

#if 0
static u8 *utilLoadRarFile(const char *file,
                           bool (*accept)(const char *),
                           u8 *data,
                           int &size)
{
  char buffer[2048];

  ArchiveList_struct *rarList = NULL;
  if(urarlib_list((void *)file, (ArchiveList_struct *)&rarList))
    {
      ArchiveList_struct *p = rarList;

      bool found = false;
      while(p)
        {
          if(accept(p->item.Name))
            {
              strcpy(buffer, p->item.Name);
              found = true;
              break;
            }
          p = p->next;
        }
      if(found)
        {
          void *memory = NULL;
          unsigned long lsize = 0;
          size = p->item.UnpSize;
          int r = urarlib_get((void *)&memory, &lsize, buffer, (void *)file, "");
          if(!r)
            {
              systemMessage(MSG_ERROR_READING_IMAGE,
                            N_("Error reading image %s"), buffer);
              urarlib_freelist(rarList);
              return NULL;
            }
          u8 *image = (u8 *)memory;
          if(data != NULL)
            {
              memcpy(image, data, size);
            }
          urarlib_freelist(rarList);
          return image;
        }
      systemMessage(MSG_NO_IMAGE_ON_ZIP,
                    N_("No image found on RAR file %s"), file);
      urarlib_freelist(rarList);
      return NULL;
    }
  // nothing found
  return NULL;
}
#endif

u8 *utilLoad(const char *file,
             bool (*accept)(const char *),
             u8 *data,
             int &size)
{
  if(utilIsZipFile(file))
    {
      return utilLoadFromZip(file, accept, data, size);
    }
  if(utilIsGzipFile(file))
    {
      return utilLoadGzipFile(file, accept, data, size);
    }
#if 0
  if(utilIsRarFile(file))
    {
      return utilLoadRarFile(file, accept, data, size);
    }
#endif

  u8 *image = data;

  FILE* f = gen_fopen(file, "rb");

  if(!f)
    {
      systemMessage(MSG_ERROR_OPENING_IMAGE, N_("Error opening image %s"), file);
      return NULL;
    }

  gen_fseek(f,0,SEEK_END);
  int fileSize = ftell(f);

  gen_fseek(f,0,SEEK_SET);
  if(size == 0)
    size = fileSize;

  if(image == NULL)
    {
      image = (u8 *)malloc(utilGetSize(size));
      if(image == NULL)
        {
          systemMessage(MSG_OUT_OF_MEMORY, N_("Failed to allocate memory for %s"),
                        "data");
          gen_fclose(f);
          return NULL;
        }
      size = fileSize;
    }
  int read = fileSize <= size ? fileSize : size;
  int r = gen_fread(image, 1, read, f);
  gen_fclose(f);

  if(r != (int)read)
    {
      systemMessage(MSG_ERROR_READING_IMAGE,
                    N_("Error reading image %s"), file);
      if(data == NULL)
        free(image);
      return NULL;
    }

  size = fileSize;

  return image;
}

void utilWriteInt(gzFile gzFile, int i)
{
  utilGzWrite(gzFile, &i, sizeof(int));
}

int utilReadInt(gzFile gzFile)
{
  int i = 0;
  utilGzRead(gzFile, &i, sizeof(int));
  return i;
}

void utilReadData(gzFile gzFile, variable_desc* data)
{
  while(data->address)
    {
      utilGzRead(gzFile, data->address, data->size);
      data++;
    }
}

void utilWriteData(gzFile gzFile, variable_desc *data)
{
  while(data->address)
    {
      utilGzWrite(gzFile, data->address, data->size);
      data++;
    }
}

gzFile utilGzOpen(const char *file, const char *mode)
{
  utilGzWriteFunc = (int (*)(void *,void * const, unsigned int))gzwrite;
  utilGzReadFunc = gzread;
  utilGzCloseFunc = gzclose;

  return gzopen(file, mode);
}

gzFile utilMemGzOpen(char *memory, int available, char *mode)
{
//  utilGzWriteFunc = memgzwrite;
  utilGzReadFunc = memgzread;
  utilGzCloseFunc = memgzclose;

  return memgzopen(memory, available, mode);
}

int utilGzWrite(gzFile file, const voidp buffer, unsigned int len)
{
  return utilGzWriteFunc(file, buffer, len);
}

int utilGzRead(gzFile file, voidp buffer, unsigned int len)
{
  return utilGzReadFunc(file, buffer, len);
}

int utilGzClose(gzFile file)
{
  return utilGzCloseFunc(file);
}

long utilGzMemTell(gzFile file)
{
  return memtell(file);
}

void utilGBAFindSave(const u8 *data, const int size)
{
  u32 *p = (u32 *)data;
  u32 *end = (u32 *)(data + size);
  int saveType = 0;
  int flashSize = 0x10000;
  bool rtcFound = false;

  while(p  < end)
    {
      u32 d = READ32LE(p);

      if(d == 0x52504545)
        {
          if(memcmp(p, "EEPROM_", 7) == 0)
            {
              if(saveType == 0)
                saveType = 1;
            }
        }
      else if (d == 0x4D415253)
        {
          if(memcmp(p, "SRAM_", 5) == 0)
            {
              if(saveType == 0)
                saveType = 2;
            }
        }
      else if (d == 0x53414C46)
        {
          if(memcmp(p, "FLASH1M_", 8) == 0)
            {
              if(saveType == 0)
                {
                  saveType = 3;
                  flashSize = 0x20000;
                }
            }
          else if(memcmp(p, "FLASH", 5) == 0)
            {
              if(saveType == 0)
                {
                  saveType = 3;
                  flashSize = 0x10000;
                }
            }
        }
      else if (d == 0x52494953)
        {
          if(memcmp(p, "SIIRTC_V", 8) == 0)
            rtcFound = true;
        }
      p++;
    }
  // if no matches found, then set it to NONE
  if(saveType == 0)
    {
      saveType = 5;
    }
  rtcEnable(rtcFound);
  cpuSaveType = saveType;
  flashSetSize(flashSize);
}