--- /dev/null
+/*
+ * PicoDrive
+ * (C) notaz, 2006-2010,2013
+ *
+ * This work is licensed under the terms of MAME license.
+ * See COPYING file in the top-level directory.
+ */
+
+#include <string.h>
+#include "pico_int.h"
+#include "cd/cue.h"
+
+unsigned char media_id_header[0x100];
+
+static void strlwr_(char *string)
+{
+ char *p;
+ for (p = string; *p; p++)
+ if ('A' <= *p && *p <= 'Z')
+ *p += 'a' - 'A';
+}
+
+static void get_ext(const char *file, char *ext)
+{
+ const char *p;
+
+ p = file + strlen(file) - 4;
+ if (p < file) p = file;
+ strncpy(ext, p, 4);
+ ext[4] = 0;
+ strlwr_(ext);
+}
+
+static int detect_media(const char *fname)
+{
+ static const short sms_offsets[] = { 0x7ff0, 0x3ff0, 0x1ff0 };
+ static const char *sms_exts[] = { "sms", "gg", "sg" };
+ static const char *md_exts[] = { "gen", "bin", "smd" };
+ char buff0[32], buff[32];
+ unsigned short *d16;
+ pm_file *pmf;
+ char ext[5];
+ int i;
+
+ get_ext(fname, ext);
+
+ // detect wrong extensions
+ if (!strcmp(ext, ".srm") || !strcmp(ext, "s.gz") || !strcmp(ext, ".mds")) // s.gz ~ .mds.gz
+ return PM_BAD_DETECT;
+
+ /* don't believe in extensions, except .cue */
+ if (strcasecmp(ext, ".cue") == 0)
+ return PM_CD;
+
+ pmf = pm_open(fname);
+ if (pmf == NULL)
+ return PM_BAD_DETECT;
+
+ if (pm_read(buff0, 32, pmf) != 32) {
+ pm_close(pmf);
+ return PM_BAD_DETECT;
+ }
+
+ if (strncasecmp("SEGADISCSYSTEM", buff0 + 0x00, 14) == 0 ||
+ strncasecmp("SEGADISCSYSTEM", buff0 + 0x10, 14) == 0) {
+ pm_close(pmf);
+ return PM_CD;
+ }
+
+ /* check for SMD evil */
+ if (pmf->size >= 0x4200 && (pmf->size & 0x3fff) == 0x200) {
+ if (pm_seek(pmf, sms_offsets[0] + 0x200, SEEK_SET) == sms_offsets[0] + 0x200 &&
+ pm_read(buff, 16, pmf) == 16 &&
+ strncmp("TMR SEGA", buff, 8) == 0)
+ goto looks_like_sms;
+
+ /* could parse further but don't bother */
+ goto extension_check;
+ }
+
+ /* MD header? Act as TMSS BIOS here */
+ if (pm_seek(pmf, 0x100, SEEK_SET) == 0x100 && pm_read(buff, 16, pmf) == 16) {
+ if (strncmp(buff, "SEGA", 4) == 0 || strncmp(buff, " SEG", 4) == 0)
+ goto looks_like_md;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(sms_offsets); i++) {
+ if (pm_seek(pmf, sms_offsets[i], SEEK_SET) != sms_offsets[i])
+ continue;
+
+ if (pm_read(buff, 16, pmf) != 16)
+ continue;
+
+ if (strncmp("TMR SEGA", buff, 8) == 0)
+ goto looks_like_sms;
+ }
+
+extension_check:
+ /* probably some headerless thing. Maybe check the extension after all. */
+ for (i = 0; i < ARRAY_SIZE(md_exts); i++)
+ if (strcasecmp(pmf->ext, md_exts[i]) == 0)
+ goto looks_like_md;
+
+ for (i = 0; i < ARRAY_SIZE(sms_exts); i++)
+ if (strcasecmp(pmf->ext, sms_exts[i]) == 0)
+ goto looks_like_sms;
+
+ /* If everything else fails, make a guess on the reset vector */
+ d16 = (unsigned short *)(buff0 + 4);
+ if ((((d16[0] << 16) | d16[1]) & 0xffffff) >= pmf->size) {
+ lprintf("bad MD reset vector, assuming SMS\n");
+ goto looks_like_sms;
+ }
+
+looks_like_md:
+ pm_close(pmf);
+ return PM_MD_CART;
+
+looks_like_sms:
+ pm_close(pmf);
+ return PM_MARK3;
+}
+
+/* checks if fname points to valid MegaCD image */
+int PicoCdCheck(const char *fname_in, int *pregion)
+{
+ const char *fname = fname_in;
+ unsigned char buf[32];
+ pm_file *cd_f;
+ int region = 4; // 1: Japan, 4: US, 8: Europe
+ char ext[5];
+ cue_track_type type = CT_UNKNOWN;
+ cue_data_t *cue_data = NULL;
+
+ get_ext(fname_in, ext);
+ if (strcasecmp(ext, ".cue") == 0) {
+ cue_data = cue_parse(fname_in);
+ if (cue_data != NULL) {
+ fname = cue_data->tracks[1].fname;
+ type = cue_data->tracks[1].type;
+ }
+ else
+ return -1;
+ }
+
+ cd_f = pm_open(fname);
+ if (cue_data != NULL)
+ cue_destroy(cue_data);
+
+ if (cd_f == NULL) return 0; // let the upper level handle this
+
+ if (pm_read(buf, 32, cd_f) != 32) {
+ pm_close(cd_f);
+ return -1;
+ }
+
+ if (!strncasecmp("SEGADISCSYSTEM", (char *)buf+0x00, 14)) {
+ if (type && type != CT_ISO)
+ elprintf(EL_STATUS, ".cue has wrong type: %i", type);
+ type = CT_ISO; // Sega CD (ISO)
+ }
+ if (!strncasecmp("SEGADISCSYSTEM", (char *)buf+0x10, 14)) {
+ if (type && type != CT_BIN)
+ elprintf(EL_STATUS, ".cue has wrong type: %i", type);
+ type = CT_BIN; // Sega CD (BIN)
+ }
+
+ if (type == CT_UNKNOWN) {
+ pm_close(cd_f);
+ return 0;
+ }
+
+ pm_seek(cd_f, (type == CT_ISO) ? 0x100 : 0x110, SEEK_SET);
+ pm_read(media_id_header, sizeof(media_id_header), cd_f);
+
+ /* it seems we have a CD image here. Try to detect region now.. */
+ pm_seek(cd_f, (type == CT_ISO) ? 0x100+0x10B : 0x110+0x10B, SEEK_SET);
+ pm_read(buf, 1, cd_f);
+ pm_close(cd_f);
+
+ if (buf[0] == 0x64) region = 8; // EU
+ if (buf[0] == 0xa1) region = 1; // JAP
+
+ lprintf("detected %s Sega/Mega CD image with %s region\n",
+ type == CT_BIN ? "BIN" : "ISO", region != 4 ? (region == 8 ? "EU" : "JAP") : "USA");
+
+ if (pregion != NULL)
+ *pregion = region;
+
+ return type;
+}
+
+enum media_type_e PicoLoadMedia(const char *filename,
+ const char *carthw_cfg_fname,
+ const char *(*get_bios_filename)(int *region, const char *cd_fname),
+ void (*do_region_override)(const char *media_filename))
+{
+ const char *rom_fname = filename;
+ enum media_type_e media_type;
+ cd_img_type cd_img_type = CIT_NOT_CD;
+ unsigned char *rom_data = NULL;
+ unsigned int rom_size = 0;
+ pm_file *rom = NULL;
+ int cd_region = 0;
+ int ret;
+
+ media_type = detect_media(filename);
+ if (media_type == PM_BAD_DETECT)
+ goto out;
+
+ if ((PicoAHW & PAHW_MCD) && Pico_mcd != NULL)
+ Stop_CD();
+ PicoCartUnload();
+ PicoAHW = 0;
+
+ if (media_type == PM_CD)
+ {
+ // check for MegaCD image
+ cd_img_type = PicoCdCheck(filename, &cd_region);
+ if (cd_img_type >= 0 && cd_img_type != CIT_NOT_CD)
+ {
+ // valid CD image, ask frontend for BIOS..
+ rom_fname = NULL;
+ if (get_bios_filename != NULL)
+ rom_fname = get_bios_filename(&cd_region, filename);
+ if (rom_fname == NULL) {
+ media_type = PM_BAD_CD_NO_BIOS;
+ goto out;
+ }
+
+ PicoAHW |= PAHW_MCD;
+ }
+ else {
+ media_type = PM_BAD_CD;
+ goto out;
+ }
+ }
+ else if (media_type == PM_MARK3) {
+ lprintf("detected SMS ROM\n");
+ PicoAHW = PAHW_SMS;
+ }
+
+ rom = pm_open(rom_fname);
+ if (rom == NULL) {
+ lprintf("Failed to open ROM");
+ media_type = PM_ERROR;
+ goto out;
+ }
+
+ ret = PicoCartLoad(rom, &rom_data, &rom_size, (PicoAHW & PAHW_SMS) ? 1 : 0);
+ pm_close(rom);
+ if (ret != 0) {
+ if (ret == 2) lprintf("Out of memory");
+ else if (ret == 3) lprintf("Read failed");
+ else lprintf("PicoCartLoad() failed.");
+ media_type = PM_ERROR;
+ goto out;
+ }
+
+ // detect wrong files
+ if (strncmp((char *)rom_data, "Pico", 4) == 0) {
+ lprintf("savestate selected?\n");
+ media_type = PM_BAD_DETECT;
+ goto out;
+ }
+
+ if (!(PicoAHW & PAHW_SMS)) {
+ unsigned short *d = (unsigned short *)(rom_data + 4);
+ if ((((d[0] << 16) | d[1]) & 0xffffff) >= (int)rom_size) {
+ lprintf("bad reset vector\n");
+ media_type = PM_BAD_DETECT;
+ goto out;
+ }
+ }
+
+ // load config for this ROM (do this before insert to get correct region)
+ if (!(PicoAHW & PAHW_MCD)) {
+ memcpy(media_id_header, rom_data + 0x100, sizeof(media_id_header));
+ if (do_region_override != NULL)
+ do_region_override(filename);
+ }
+
+ if (PicoCartInsert(rom_data, rom_size, carthw_cfg_fname)) {
+ media_type = PM_ERROR;
+ goto out;
+ }
+ rom_data = NULL; // now belongs to PicoCart
+
+ // insert CD if it was detected
+ if (cd_img_type != CIT_NOT_CD) {
+ ret = Insert_CD(filename, cd_img_type);
+ if (ret != 0) {
+ PicoCartUnload();
+ media_type = PM_BAD_CD;
+ goto out;
+ }
+ }
+
+out:
+ if (rom_data)
+ free(rom_data);
+ return media_type;
+}
+
+// vim:shiftwidth=2:ts=2:expandtab
notaz.gp2x.de / picodrive.git / blobdiff