Added Rom header core definition and two cores:

- standard one open a "normal" rom
- gzip one opens a gzip'ed rom
Now it should be easy to add new cores to handle other compression formats

desmume/src/Makefile.am

@@ -11,6 +11,7 @@ libdesmume_a_SOURCES = \
 	GPU.c GPU.h \
         mc.c mc.h \
         MMU.c MMU.h NDSSystem.c NDSSystem.h registers.h \
+	ROMReader.c ROMReader.h \
         saves.c saves.h \
         SPU.c SPU.h \
         thumb_instructions.c thumb_instructions.h

desmume/src/NDSSystem.c

@@ -23,6 +23,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include "ROMReader.h"
+
 NDSSystem nds;
 
 int NDS_Init(void) {
@@ -171,62 +173,35 @@ int NDS_LoadROM(const char *filename, int bmtype, u32 bmsize)
 {
    int i;
    int type;
-   const char *p = filename;
-#ifdef HAVE_LIBZ
-   int gz = 0;
-   char* read_buf[1024];
-#endif
+   char * p;
    
-   FILE *file;
+   ROMReader_struct * reader;
+   FILE * file;
    u32 size, mask;
    u8 *data;
+   char * noext;
 
    if (filename == NULL)
       return -1;
+
+   noext = strdup(filename);
    
-#ifdef HAVE_LIBZ
-   if(!strcasecmp(".gz", &filename[strlen(filename) - 3])){
-   	gz = 1;
-	p -= 3;
-   }
-#endif
+   reader = ROMReaderInit(&noext);
    type = ROM_NDS;
-	
+
+   p = noext;
    p += strlen(p);
    p -= strlen(DSGBA_EXTENSTION);
 
    if(memcmp(p, DSGBA_EXTENSTION, strlen(DSGBA_EXTENSTION)) == 0)
       type = ROM_DSGBA;
 
-#ifdef HAVE_LIBZ
-   if(gz)
-   {
-	if((file = (FILE *)gzopen(filename, "rb")) == 0)
-	   return -1;
-	while (gzeof (file) == 0)
-	   size += gzread(file,read_buf, 1024);
-	gzrewind(file);
-   }
-   else
-   {
-#endif
-   	if ((file = fopen(filename, "rb")) == NULL)
-	   return -1;
-	fseek(file, 0, SEEK_END);
-	size = ftell(file);
-	fseek(file, 0, SEEK_SET);
-#ifdef HAVE_LIBZ
-   }
-#endif
-	
+   file = reader->Init(filename);
+   size = reader->Size(file);
+
    if(type == ROM_DSGBA)
    {
-#ifdef HAVE_LIBZ
-      if(gz)
-         gzseek(file, DSGBA_LOADER_SIZE, SEEK_SET);
-      else
-#endif
-         fseek(file, DSGBA_LOADER_SIZE, SEEK_SET);
+      reader->Seek(file, DSGBA_LOADER_SIZE, SEEK_SET);
       size -= DSGBA_LOADER_SIZE;
    }
 	
@@ -244,29 +219,12 @@ int NDS_LoadROM(const char *filename, int bmtype, u32 bmsize)
 
    if ((data = (u8*)malloc(mask + 1)) == NULL)
    {
-#ifdef HAVE_LIBZ
-      if(gz)
-        gzclose(file);
-      else
-#endif
-        fclose(file);
+      reader->DeInit(file);
       return -1;
    }
 
-#ifdef HAVE_LIBZ
-   if(gz)
-   {
-      i = gzread(file,data,size);
-      gzclose(file);
-   }
-   else
-   { 
-#endif
-      i = fread(data, 1, size, file);	
-      fclose(file);
-#ifdef HAVE_LIBZ
-   }
-#endif
+   i = reader->Read(file, data, size);
+   reader->DeInit(file);
    MMU_unsetRom();
    NDS_SetROM(data, mask);
    NDS_Reset();
@@ -285,20 +243,14 @@ int NDS_LoadROM(const char *filename, int bmtype, u32 bmsize)
       szRomBaseName[strlen(szRomBaseName)-4] = 0x00;
 
    // Setup Backup Memory
-   p = strdup(filename);
-#ifdef HAVE_LIBZ
-   if(gz)
-     strcpy(p+strlen(p)-3, "");
-#endif
-
    if(type == ROM_DSGBA)
-      strcpy(p+strlen(p)-strlen(DSGBA_EXTENSTION), ".sav");
+      strcpy(noext + strlen(noext) - strlen(DSGBA_EXTENSTION), ".sav");
    else
-      strcpy(p+strlen(p)-4, ".sav");
+      strcpy(noext + strlen(noext) - 4, ".sav");
 
    mc_realloc(&MMU.bupmem, bmtype, bmsize);
-   mc_load_file(&MMU.bupmem, p);
-   free(p);
+   mc_load_file(&MMU.bupmem, noext);
+   free(noext);
 
    return i;
 }

desmume/src/ROMReader.c

@@ -0,0 +1,118 @@
+#include "ROMReader.h"
+
+#include <stdio.h>
+
+ROMReader_struct * ROMReaderInit(const char ** filename)
+{
+	if(!strcasecmp(".gz", *filename + (strlen(*filename) - 3)))
+	{
+		*filename -= 3;
+		return &GZIPROMReader;
+	}
+	else
+	{
+		return &STDROMReader;
+	}
+}
+
+void * STDROMReaderInit(const char * filename);
+void STDROMReaderDeInit(void *);
+u32 STDROMReaderSize(void *);
+int STDROMReaderSeek(void *, int, int);
+int STDROMReaderRead(void *, void *, u32);
+
+ROMReader_struct STDROMReader =
+{
+	ROMREADER_STD,
+	"Standard ROM Reader",
+	STDROMReaderInit,
+	STDROMReaderDeInit,
+	STDROMReaderSize,
+	STDROMReaderSeek,
+	STDROMReaderRead
+};
+
+void * STDROMReaderInit(const char * filename)
+{
+	return (void *) fopen(filename, "rb");
+}
+
+void STDROMReaderDeInit(void * file)
+{
+	fclose(file);
+}
+
+u32 STDROMReaderSize(void * file)
+{
+	u32 size;
+
+	fseek(file, 0, SEEK_END);
+	size = ftell(file);
+	fseek(file, 0, SEEK_SET);
+
+	return size;
+}
+
+int STDROMReaderSeek(void * file, int offset, int whence)
+{
+	return fseek(file, offset, whence);
+}
+
+int STDROMReaderRead(void * file, void * buffer, u32 size)
+{
+	return fread(buffer, 1, size, file);
+}
+
+#ifdef HAVE_LIBZ
+void * GZIPROMReaderInit(const char * filename);
+void GZIPROMReaderDeInit(void *);
+u32 GZIPROMReaderSize(void *);
+int GZIPROMReaderSeek(void *, int, int);
+int GZIPROMReaderRead(void *, void *, u32);
+
+ROMReader_struct GZIPROMReader =
+{
+	ROMREADER_GZIP,
+	"Gzip ROM Reader",
+	GZIPROMReaderInit,
+	GZIPROMReaderDeInit,
+	GZIPROMReaderSize,
+	GZIPROMReaderSeek,
+	GZIPROMReaderRead
+};
+
+void * GZIPROMReaderInit(const char * filename)
+{
+	return gzopen(filename, "rb");
+}
+
+void GZIPROMReaderDeInit(void * file)
+{
+	gzclose(file);
+}
+
+u32 GZIPROMReaderSize(void * file)
+{
+	char useless[1024];
+	u32 size;
+
+	/* FIXME this function should first save the current
+	 * position and restore it after size calculation */
+	gzrewind(file);
+	while (gzeof (file) == 0)
+		size += gzread(file, useless, 1024);
+	gzrewind(file);
+
+	return size;
+}
+
+int GZIPROMReaderSeek(void * file, int offset, int whence)
+{
+	return gzseek(file, offset, whence);
+}
+
+int GZIPROMReaderRead(void * file, void * buffer, u32 size)
+{
+	return gzread(file, buffer, size);
+}
+#endif

desmume/src/ROMReader.h

@@ -0,0 +1,23 @@
+#include "types.h"
+
+#define ROMREADER_DEFAULT -1
+#define ROMREADER_STD 0
+#define ROMREADER_GZIP 1
+
+typedef struct
+{
+	int id;
+	const char * Name;
+	void * (*Init)(const char * filename);
+	void (*DeInit)(void * file);
+	u32 (*Size)(void * file);
+	int (*Seek)(void * file, int offset, int whence);
+	int (*Read)(void * file, void * buffer, u32 size);
+} ROMReader_struct;
+
+extern ROMReader_struct STDROMReader;
+#ifdef HAVE_LIBZ
+extern ROMReader_struct GZIPROMReader;
+#endif
+
+ROMReader_struct * ROMReaderInit(const char ** filename);