initial import

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@2 be3aeb3a-fb24-0410-a615-afba39da0efa

platform/win32/GenaDrive/Rom.cpp

@@ -0,0 +1,143 @@
+
+#include "app.h"
+#include "Unzip.h"
+
+unsigned char *RomData=NULL;
+int RomLen=0;
+char RomName[260]="";
+
+
+static int Byteswap(unsigned char *data,int len)
+{
+  int i=0;
+
+  if (len<2) return 1; // Too short
+
+  do
+  {
+    unsigned short *pd=(unsigned short *)(data+i);
+    int word=*pd; // Get word
+
+    word=(word<<8)|(word>>8); // Byteswap it
+    *pd=(unsigned short)word; // Put word
+    i+=2;
+  }  
+  while (i+2<=len);
+
+  return 0;
+}
+
+// Interleve a 16k block and byteswap
+static int InterleveBlock(unsigned char *dest,unsigned char *src)
+{
+  int i=0;
+  for (i=0;i<0x2000;i++) dest[(i<<1)  ]=src[       i]; // Odd
+  for (i=0;i<0x2000;i++) dest[(i<<1)+1]=src[0x2000+i]; // Even
+  return 0;
+}
+
+// Decode a SMD file
+static int DecodeSmd(unsigned char *data,int len)
+{
+  unsigned char *temp=NULL;
+  int i=0;
+
+  temp=(unsigned char *)malloc(0x4000);
+  if (temp==NULL) return 1;
+  memset(temp,0,0x4000);
+
+  // Interleve each 16k block and shift down by 0x200:
+  for (i=0; i+0x4200<=len; i+=0x4000)
+  {
+    InterleveBlock(temp,data+0x200+i); // Interleve 16k to temporary buffer
+    memcpy(data+i,temp,0x4000); // Copy back in
+  }
+
+  free(temp);
+  return 0;
+}
+
+int RomLoad()
+{
+  FILE *file=NULL;
+  char *name=NULL;
+  int nameLen=0;
+  int fileLen=0,space=0;
+  Unzip unzip;
+
+  name=RomName;
+
+  file=fopen(name,"rb"); if (file==NULL) return 1;
+
+  nameLen=strlen(name);
+  if (stricmp(name+nameLen-4,".zip")==0) unzip.file=file; // Open as zip file
+
+  if (unzip.file)
+  {
+    int ret=0;
+
+    ret=unzip.fileOpen(); // Get first entry
+    if (ret==0)
+    {
+      fileLen=unzip.dataLen;  // Length of file
+      // Switch to using the name in the zip file:
+      name=unzip.name; nameLen=strlen(name);
+    }
+    else
+    {
+      unzip.file=NULL;
+    }
+
+  }
+  else
+  {
+    // Find out the length of the file:
+    fseek(file,0,SEEK_END); fileLen=ftell(file);
+    fseek(file,0,SEEK_SET);
+  }
+
+  // Allocate space for it:
+  space=(fileLen+0x3fff)&~0x3fff;
+
+  RomData=(unsigned char *)malloc(space);
+  if (RomData==NULL) { fclose(file); return 1; }
+  memset(RomData,0,space);
+
+  // Read in file:
+  if (unzip.file) unzip.fileDecode(RomData);
+  else fread(RomData,1,fileLen,file);
+
+  unzip.fileClose();
+
+  fclose(file);
+  unzip.file=file=NULL;
+
+  RomLen=fileLen;
+
+  // Check for SMD:
+  if ((fileLen&0x3fff)==0x200)
+  {
+    // Decode and byteswap:
+    DecodeSmd(RomData,RomLen);
+    RomLen-=0x200;
+  }
+  else
+  {
+    // Just byteswap:
+    Byteswap(RomData,RomLen);
+  }
+
+  PicoCartInsert(RomData,RomLen);
+
+  return 0;
+}
+
+void RomFree()
+{
+//  PicoCartInsert(NULL,0); // Unplug rom
+
+  if (RomData) free(RomData);
+  RomData=NULL; RomLen=0;
+  memset(RomName,0,sizeof(RomName));
+}
+