[picodrive.git] / pico / media.c

/*
 * 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
Commit	Line	Data
4c2e3554	1	/*
	2	* PicoDrive
	3	* (C) notaz, 2006-2010,2013
	4	*
	5	* This work is licensed under the terms of MAME license.
	6	* See COPYING file in the top-level directory.
	7	*/
	8
	9	#include <string.h>
	10	#include "pico_int.h"
	11	#include "cd/cue.h"
	12
	13	unsigned char media_id_header[0x100];
	14
	15	static void strlwr_(char *string)
	16	{
	17	char *p;
	18	for (p = string; *p; p++)
	19	if ('A' <= p && p <= 'Z')
	20	*p += 'a' - 'A';
	21	}
	22
	23	static void get_ext(const char file, char ext)
	24	{
	25	const char *p;
	26
	27	p = file + strlen(file) - 4;
	28	if (p < file) p = file;
	29	strncpy(ext, p, 4);
	30	ext[4] = 0;
	31	strlwr_(ext);
	32	}
	33
	34	static int detect_media(const char *fname)
	35	{
	36	static const short sms_offsets[] = { 0x7ff0, 0x3ff0, 0x1ff0 };
	37	static const char *sms_exts[] = { "sms", "gg", "sg" };
	38	static const char *md_exts[] = { "gen", "bin", "smd" };
	39	char buff0[32], buff[32];
	40	unsigned short *d16;
	41	pm_file *pmf;
	42	char ext[5];
	43	int i;
	44
	45	get_ext(fname, ext);
	46
	47	// detect wrong extensions
	48	if (!strcmp(ext, ".srm") \|\| !strcmp(ext, "s.gz") \|\| !strcmp(ext, ".mds")) // s.gz ~ .mds.gz
	49	return PM_BAD_DETECT;
	50
	51	/* don't believe in extensions, except .cue */
	52	if (strcasecmp(ext, ".cue") == 0)
	53	return PM_CD;
	54
	55	pmf = pm_open(fname);
	56	if (pmf == NULL)
	57	return PM_BAD_DETECT;
	58
	59	if (pm_read(buff0, 32, pmf) != 32) {
	60	pm_close(pmf);
	61	return PM_BAD_DETECT;
	62	}
	63
	64	if (strncasecmp("SEGADISCSYSTEM", buff0 + 0x00, 14) == 0 \|\|
65	strncasecmp("SEGADISCSYSTEM", buff0 + 0x10, 14) == 0) {
66	pm_close(pmf);
67	return PM_CD;
68	}
69
70	/* check for SMD evil */
71	if (pmf->size >= 0x4200 && (pmf->size & 0x3fff) == 0x200) {
72	if (pm_seek(pmf, sms_offsets[0] + 0x200, SEEK_SET) == sms_offsets[0] + 0x200 &&
73	pm_read(buff, 16, pmf) == 16 &&
74	strncmp("TMR SEGA", buff, 8) == 0)
75	goto looks_like_sms;
76
77	/* could parse further but don't bother */
78	goto extension_check;
79	}
80
81	/* MD header? Act as TMSS BIOS here */
82	if (pm_seek(pmf, 0x100, SEEK_SET) == 0x100 && pm_read(buff, 16, pmf) == 16) {
83	if (strncmp(buff, "SEGA", 4) == 0 \|\| strncmp(buff, " SEG", 4) == 0)
84	goto looks_like_md;
85	}
86
87	for (i = 0; i < ARRAY_SIZE(sms_offsets); i++) {
88	if (pm_seek(pmf, sms_offsets[i], SEEK_SET) != sms_offsets[i])
89	continue;
90
91	if (pm_read(buff, 16, pmf) != 16)
92	continue;
93
94	if (strncmp("TMR SEGA", buff, 8) == 0)
95	goto looks_like_sms;
96	}
97
98	extension_check:
99	/* probably some headerless thing. Maybe check the extension after all. */
100	for (i = 0; i < ARRAY_SIZE(md_exts); i++)
101	if (strcasecmp(pmf->ext, md_exts[i]) == 0)
102	goto looks_like_md;
103
104	for (i = 0; i < ARRAY_SIZE(sms_exts); i++)
105	if (strcasecmp(pmf->ext, sms_exts[i]) == 0)
106	goto looks_like_sms;
107
108	/* If everything else fails, make a guess on the reset vector */
109	d16 = (unsigned short *)(buff0 + 4);
110	if ((((d16[0] << 16) \| d16[1]) & 0xffffff) >= pmf->size) {
111	lprintf("bad MD reset vector, assuming SMS\n");
112	goto looks_like_sms;
113	}
114
115	looks_like_md:
116	pm_close(pmf);
117	return PM_MD_CART;
118
119	looks_like_sms:
120	pm_close(pmf);
121	return PM_MARK3;
122	}
123
124	/* checks if fname points to valid MegaCD image */
125	int PicoCdCheck(const char fname_in, int pregion)
126	{
127	const char *fname = fname_in;
128	unsigned char buf[32];
129	pm_file *cd_f;
130	int region = 4; // 1: Japan, 4: US, 8: Europe
131	char ext[5];
132	cue_track_type type = CT_UNKNOWN;
133	cue_data_t *cue_data = NULL;
134
135	get_ext(fname_in, ext);
136	if (strcasecmp(ext, ".cue") == 0) {
137	cue_data = cue_parse(fname_in);
138	if (cue_data != NULL) {
139	fname = cue_data->tracks[1].fname;
140	type = cue_data->tracks[1].type;
141	}
142	else
143	return -1;
144	}
145
146	cd_f = pm_open(fname);
147	if (cue_data != NULL)
148	cue_destroy(cue_data);
149
150	if (cd_f == NULL) return 0; // let the upper level handle this
151
152	if (pm_read(buf, 32, cd_f) != 32) {
153	pm_close(cd_f);
154	return -1;
155	}
156
157	if (!strncasecmp("SEGADISCSYSTEM", (char *)buf+0x00, 14)) {
158	if (type && type != CT_ISO)
159	elprintf(EL_STATUS, ".cue has wrong type: %i", type);
160	type = CT_ISO; // Sega CD (ISO)
161	}
162	if (!strncasecmp("SEGADISCSYSTEM", (char *)buf+0x10, 14)) {
163	if (type && type != CT_BIN)
164	elprintf(EL_STATUS, ".cue has wrong type: %i", type);
165	type = CT_BIN; // Sega CD (BIN)
166	}
167
168	if (type == CT_UNKNOWN) {
169	pm_close(cd_f);
170	return 0;
171	}
172
173	pm_seek(cd_f, (type == CT_ISO) ? 0x100 : 0x110, SEEK_SET);
174	pm_read(media_id_header, sizeof(media_id_header), cd_f);
175
176	/* it seems we have a CD image here. Try to detect region now.. */
177	pm_seek(cd_f, (type == CT_ISO) ? 0x100+0x10B : 0x110+0x10B, SEEK_SET);
178	pm_read(buf, 1, cd_f);
179	pm_close(cd_f);
180
181	if (buf[0] == 0x64) region = 8; // EU
182	if (buf[0] == 0xa1) region = 1; // JAP
183
184	lprintf("detected %s Sega/Mega CD image with %s region\n",
185	type == CT_BIN ? "BIN" : "ISO", region != 4 ? (region == 8 ? "EU" : "JAP") : "USA");
186
187	if (pregion != NULL)
188	*pregion = region;
189
190	return type;
191	}
192
193	enum media_type_e PicoLoadMedia(const char *filename,
194	const char *carthw_cfg_fname,
195	const char (get_bios_filename)(int region, const char cd_fname),
196	void (do_region_override)(const char media_filename))
197	{
198	const char *rom_fname = filename;
199	enum media_type_e media_type;
200	cd_img_type cd_img_type = CIT_NOT_CD;
201	unsigned char *rom_data = NULL;
202	unsigned int rom_size = 0;
203	pm_file *rom = NULL;
204	int cd_region = 0;
205	int ret;
206
207	media_type = detect_media(filename);
208	if (media_type == PM_BAD_DETECT)
209	goto out;
210
211	if ((PicoAHW & PAHW_MCD) && Pico_mcd != NULL)
212	Stop_CD();
213	PicoCartUnload();
214	PicoAHW = 0;
215
216	if (media_type == PM_CD)
217	{
218	// check for MegaCD image
219	cd_img_type = PicoCdCheck(filename, &cd_region);
220	if (cd_img_type >= 0 && cd_img_type != CIT_NOT_CD)
221	{
222	// valid CD image, ask frontend for BIOS..
223	rom_fname = NULL;
224	if (get_bios_filename != NULL)
225	rom_fname = get_bios_filename(&cd_region, filename);
226	if (rom_fname == NULL) {
227	media_type = PM_BAD_CD_NO_BIOS;
228	goto out;
229	}
230
231	PicoAHW \|= PAHW_MCD;
232	}
233	else {
234	media_type = PM_BAD_CD;
235	goto out;
236	}
237	}
238	else if (media_type == PM_MARK3) {
239	lprintf("detected SMS ROM\n");
240	PicoAHW = PAHW_SMS;
241	}
242
243	rom = pm_open(rom_fname);
244	if (rom == NULL) {
245	lprintf("Failed to open ROM");
246	media_type = PM_ERROR;
247	goto out;
248	}
249
250	ret = PicoCartLoad(rom, &rom_data, &rom_size, (PicoAHW & PAHW_SMS) ? 1 : 0);
251	pm_close(rom);
252	if (ret != 0) {
253	if (ret == 2) lprintf("Out of memory");
254	else if (ret == 3) lprintf("Read failed");
255	else lprintf("PicoCartLoad() failed.");
256	media_type = PM_ERROR;
257	goto out;
258	}
259
260	// detect wrong files
261	if (strncmp((char *)rom_data, "Pico", 4) == 0) {
262	lprintf("savestate selected?\n");
263	media_type = PM_BAD_DETECT;
264	goto out;
265	}
266
267	if (!(PicoAHW & PAHW_SMS)) {
268	unsigned short d = (unsigned short )(rom_data + 4);
269	if ((((d[0] << 16) \| d[1]) & 0xffffff) >= (int)rom_size) {
270	lprintf("bad reset vector\n");
271	media_type = PM_BAD_DETECT;
272	goto out;
273	}
274	}
275
276	// load config for this ROM (do this before insert to get correct region)
277	if (!(PicoAHW & PAHW_MCD)) {
278	memcpy(media_id_header, rom_data + 0x100, sizeof(media_id_header));
279	if (do_region_override != NULL)
280	do_region_override(filename);
281	}
282
283	if (PicoCartInsert(rom_data, rom_size, carthw_cfg_fname)) {
284	media_type = PM_ERROR;
285	goto out;
286	}
287	rom_data = NULL; // now belongs to PicoCart
288
289	// insert CD if it was detected
290	if (cd_img_type != CIT_NOT_CD) {
291	ret = Insert_CD(filename, cd_img_type);
292	if (ret != 0) {
293	PicoCartUnload();
294	media_type = PM_BAD_CD;
295	goto out;
296	}
297	}
298
299	out:
300	if (rom_data)
301	free(rom_data);
302	return media_type;
303	}
304
305	// vim:shiftwidth=2:ts=2:expandtab