patch/gg support, 1.201 release

[picodrive.git] / Pico / Cart.c

// This is part of Pico Library\r
\r
// (c) Copyright 2004 Dave, All rights reserved.\r
// (c) Copyright 2006 notaz, All rights reserved.\r
// Free for non-commercial use.\r
\r
// For commercial use, separate licencing terms must be obtained.\r
\r
\r
#include "PicoInt.h"\r
\r
void Byteswap(unsigned char *data,int len)\r
{\r
  int i=0;\r
\r
  if (len<2) return; // Too short\r
\r
  do\r
  {\r
    unsigned short *pd=(unsigned short *)(data+i);\r
    int value=*pd; // Get 2 bytes\r
\r
    value=(value<<8)|(value>>8); // Byteswap it\r
    *pd=(unsigned short)value; // Put 2b ytes\r
    i+=2;\r
  }\r
  while (i+2<=len);\r
}\r
\r
// Interleve a 16k block and byteswap\r
static int InterleveBlock(unsigned char *dest,unsigned char *src)\r
{\r
  int i=0;\r
  for (i=0;i<0x2000;i++) dest[(i<<1)  ]=src[       i]; // Odd\r
  for (i=0;i<0x2000;i++) dest[(i<<1)+1]=src[0x2000+i]; // Even\r
  return 0;\r
}\r
\r
// Decode a SMD file\r
static int DecodeSmd(unsigned char *data,int len)\r
{\r
  unsigned char *temp=NULL;\r
  int i=0;\r
\r
  temp=(unsigned char *)malloc(0x4000);\r
  if (temp==NULL) return 1;\r
  memset(temp,0,0x4000);\r
\r
  // Interleve each 16k block and shift down by 0x200:\r
  for (i=0; i+0x4200<=len; i+=0x4000)\r
  {\r
    InterleveBlock(temp,data+0x200+i); // Interleve 16k to temporary buffer\r
    memcpy(data+i,temp,0x4000); // Copy back in\r
  }\r
\r
  free(temp);\r
  return 0;\r
}\r
\r
static unsigned char *cd_realloc(void *old, int filesize)\r
{\r
  unsigned char *rom;\r
  dprintf("sizeof(mcd_state): %i", sizeof(mcd_state));\r
  rom=realloc(old, sizeof(mcd_state));\r
  if (rom) memset(rom+0x20000, 0, sizeof(mcd_state)-0x20000);\r
  return rom;\r
}\r
\r
static unsigned char *PicoCartAlloc(int filesize)\r
{\r
  int alloc_size;\r
  unsigned char *rom;\r
\r
  if (PicoMCD & 1) return cd_realloc(NULL, filesize);\r
\r
  alloc_size=filesize+0x7ffff;\r
  if((filesize&0x3fff)==0x200) alloc_size-=0x200;\r
  alloc_size&=~0x7ffff; // use alloc size of multiples of 512K, so that memhandlers could be set up more efficiently\r
  if((filesize&0x3fff)==0x200) alloc_size+=0x200;\r
  else if(alloc_size-filesize < 4) alloc_size+=4; // padding for out-of-bound exec protection\r
  //dprintf("alloc_size: %x\n",  alloc_size);\r
\r
  // Allocate space for the rom plus padding\r
  rom=(unsigned char *)malloc(alloc_size);\r
  if(rom) memset(rom+alloc_size-0x80000,0,0x80000);\r
  return rom;\r
}\r
\r
int PicoCartLoad(FILE *f,unsigned char **prom,unsigned int *psize)\r
{\r
  unsigned char *rom=NULL; int size;\r
  if (f==NULL) return 1;\r
\r
  fseek(f,0,SEEK_END); size=ftell(f); fseek(f,0,SEEK_SET);\r
  if (size <= 0) return 1;\r
  size=(size+3)&~3; // Round up to a multiple of 4\r
\r
  // Allocate space for the rom plus padding\r
  rom=PicoCartAlloc(size);\r
  if (rom==NULL) return 1; // { fclose(f); return 1; }\r
\r
  fread(rom,1,size,f); // Load up the rom\r
\r
  // maybe we are loading MegaCD BIOS?\r
  if (!(PicoMCD&1) && size == 0x20000 && (!strncmp((char *)rom+0x124, "BOOT", 4) || !strncmp((char *)rom+0x128, "BOOT", 4))) {\r
    PicoMCD |= 1;\r
    rom = cd_realloc(rom, size);\r
  }\r
\r
  // Check for SMD:\r
  if ((size&0x3fff)==0x200) { DecodeSmd(rom,size); size-=0x200; } // Decode and byteswap SMD\r
  else Byteswap(rom,size); // Just byteswap\r
\r
  if (prom)  *prom=rom;\r
  if (psize) *psize=size;\r
\r
  return 0;\r
}\r
\r
// Insert/remove a cartridge:\r
int PicoCartInsert(unsigned char *rom,unsigned int romsize)\r
{\r
  // notaz: add a 68k "jump one op back" opcode to the end of ROM.\r
  // This will hang the emu, but will prevent nasty crashes.\r
  // note: 4 bytes are padded to every ROM\r
  if(rom != NULL)\r
    *(unsigned long *)(rom+romsize) = 0xFFFE4EFA; // 4EFA FFFE byteswapped\r
\r
  SRam.resize=1;\r
  Pico.rom=rom;\r
  Pico.romsize=romsize;\r
\r
  return PicoReset(1);\r
}\r
\r
int PicoUnloadCart(unsigned char* romdata)\r
{\r
  free(romdata);\r
  return 0;\r
}\r
\r
\r
#ifdef _UNZIP_SUPPORT\r
\r
// notaz\r
#include "../unzip/unzip.h"\r
\r
// nearly same as PicoCartLoad, but works with zipfiles\r
int CartLoadZip(const char *fname, unsigned char **prom, unsigned int *psize)\r
{\r
	unsigned char *rom=0;\r
	struct zipent* zipentry;\r
	int size;\r
	ZIP *zipfile = openzip(fname);\r
\r
	if(!zipfile) return 1;\r
\r
	// find first bin or smd\r
	while((zipentry = readzip(zipfile)) != 0)\r
	{\r
		char *ext;\r
		if(strlen(zipentry->name) < 5) continue;\r
		ext = zipentry->name+strlen(zipentry->name)-4;\r
\r
		if(!strcasecmp(ext, ".bin") || !strcasecmp(ext, ".smd") || !strcasecmp(ext, ".gen")) break;\r
	}\r
\r
	if(!zipentry) {\r
		closezip(zipfile);\r
		return 4; // no roms\r
	}\r
\r
	size = zipentry->uncompressed_size;\r
\r
	size=(size+3)&~3; // Round up to a multiple of 4\r
\r
	// Allocate space for the rom plus padding\r
	rom=PicoCartAlloc(size);\r
	if (rom==NULL) { closezip(zipfile); return 2; }\r
\r
	if(readuncompresszip(zipfile, zipentry, (char *)rom) != 0) {\r
		free(rom);\r
		rom = 0;\r
		closezip(zipfile);\r
		return 5; // unzip failed\r
	}\r
\r
	closezip(zipfile);\r
\r
        // maybe we are loading MegaCD BIOS?\r
        if (!(PicoMCD&1) && size == 0x20000 &&\r
			(!strncmp((char *)rom+0x124, "BOOT", 4) || !strncmp((char *)rom+0x128, "BOOT", 4))) {\r
		PicoMCD |= 1;\r
		rom = cd_realloc(rom, size);\r
        }\r
\r
	// Check for SMD:\r
	if ((size&0x3fff)==0x200) { DecodeSmd(rom,size); size-=0x200; } // Decode and byteswap SMD\r
	else Byteswap(rom,size); // Just byteswap\r
\r
	if (prom)  *prom=rom;\r
	if (psize) *psize=size;\r
\r
	return 0;\r
}\r
\r
#endif\r