more sms wip, better ROM detect, line callback change

[picodrive.git] / platform / common / emu.c

diff --git a/platform/common/emu.c b/platform/common/emu.c
index 1cecc39..aca54be 100644 (file)
--- a/platform/common/emu.c
+++ b/platform/common/emu.c
@@ -245,8 +245,11 @@ static int emu_cd_check(int *pregion, const char *fname_in)
 static int detect_media(const char *fname)\r
 {\r
        static const short sms_offsets[] = { 0x7ff0, 0x3ff0, 0x1ff0 };\r
+       static const char *sms_exts[] = { "sms", "gg", "sg" };\r
+       static const char *md_exts[] = { "gen", "bin", "smd" };\r
+       char buff0[32], buff[32];\r
+       unsigned short *d16;\r
        pm_file *pmf;\r
-       char buff[32];\r
        char ext[5];\r
        int i;\r
 \r
@@ -264,34 +267,69 @@ static int detect_media(const char *fname)
        if (pmf == NULL)\r
                return PM_BAD;\r
 \r
-       if (pm_read(buff, 32, pmf) != 32) {\r
+       if (pm_read(buff0, 32, pmf) != 32) {\r
                pm_close(pmf);\r
                return PM_BAD;\r
        }\r
 \r
-       if (strncasecmp("SEGADISCSYSTEM", buff + 0x00, 14) == 0 ||\r
-           strncasecmp("SEGADISCSYSTEM", buff + 0x10, 14) == 0) {\r
+       if (strncasecmp("SEGADISCSYSTEM", buff0 + 0x00, 14) == 0 ||\r
+           strncasecmp("SEGADISCSYSTEM", buff0 + 0x10, 14) == 0) {\r
                pm_close(pmf);\r
                return PM_CD;\r
        }\r
 \r
+       /* check for SMD evil */\r
+       if (pmf->size >= 0x4200 && (pmf->size & 0x3fff) == 0x200) {\r
+               if (pm_seek(pmf, sms_offsets[0] + 0x200, SEEK_SET) == sms_offsets[0] + 0x200 &&\r
+                   pm_read(buff, 16, pmf) == 16 &&\r
+                   strncmp("TMR SEGA", buff, 8) == 0)\r
+                       goto looks_like_sms;\r
+\r
+               /* could parse further but don't bother */\r
+               goto extension_check;\r
+       }\r
+\r
+       /* MD header? Act as TMSS BIOS here */\r
+       if (pm_seek(pmf, 0x100, SEEK_SET) == 0x100 && pm_read(buff, 16, pmf) == 16) {\r
+               if (strncmp(buff, "SEGA", 4) == 0 || strncmp(buff, " SEG", 4) == 0)\r
+                       goto looks_like_md;\r
+       }\r
+\r
        for (i = 0; i < array_size(sms_offsets); i++) {\r
                if (pm_seek(pmf, sms_offsets[i], SEEK_SET) != sms_offsets[i])\r
-                       goto not_mark3;         /* actually it could be but can't be detected */\r
+                       continue;\r
 \r
                if (pm_read(buff, 16, pmf) != 16)\r
-                       goto not_mark3;\r
+                       continue;\r
 \r
-               if (strncasecmp("TMR SEGA", buff, 8) == 0) {\r
-                       pm_close(pmf);\r
-                       return PM_MARK3;\r
-               }\r
+               if (strncmp("TMR SEGA", buff, 8) == 0)\r
+                       goto looks_like_sms;\r
+       }\r
+\r
+extension_check:\r
+       /* probably some headerless thing. Maybe check the extension after all. */\r
+       for (i = 0; i < array_size(md_exts); i++)\r
+               if (strcasecmp(pmf->ext, md_exts[i]) == 0)\r
+                       goto looks_like_md;\r
+\r
+       for (i = 0; i < array_size(sms_exts); i++)\r
+               if (strcasecmp(pmf->ext, sms_exts[i]) == 0)\r
+                       goto looks_like_sms;\r
+\r
+       /* If everything else fails, make a guess on the reset vector */\r
+       d16 = (unsigned short *)(buff0 + 4);\r
+       if ((((d16[0] << 16) | d16[1]) & 0xffffff) >= pmf->size) {\r
+               lprintf("bad MD reset vector, assuming SMS\n");\r
+               goto looks_like_sms;\r
        }\r
 \r
-not_mark3:\r
+looks_like_md:\r
        pm_close(pmf);\r
-       /* the main emu function is to emulate MD, so assume MD */\r
        return PM_MD_CART;\r
+\r
+looks_like_sms:\r
+       pm_close(pmf);\r
+       return PM_MARK3;\r
 }\r
 \r
 static int extract_text(char *dest, const unsigned char *src, int len, int swab)\r
@@ -450,6 +488,7 @@ int emu_reload_rom(char *rom_fname)
 \r
        shutdown_MCD();\r
        PicoPatchUnload();\r
+       PicoAHW = 0;\r
 \r
        if (media_type == PM_CD)\r
        {\r