RetroArch/libretro-common/streams/chd_stream.c
2017-12-16 14:12:38 +01:00

426 lines
10 KiB
C

/* Copyright (C) 2010-2017 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this file (chd_stream.c).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <streams/chd_stream.h>
#include <retro_endianness.h>
#include <libchdr/chd.h>
#define SECTOR_SIZE 2352
#define SUBCODE_SIZE 96
#define TRACK_PAD 4
struct chdstream
{
chd_file *chd;
/* Should we swap bytes? */
bool swab;
/* Size of frame taken from each hunk */
uint32_t frame_size;
/* Offset of data within frame */
uint32_t frame_offset;
/* Number of frames per hunk */
uint32_t frames_per_hunk;
/* First frame of track in chd */
uint32_t track_frame;
/* Byte offset where track data starts (after pregap) */
size_t track_start;
/* Byte offset where track data ends */
size_t track_end;
/* Byte offset of read cursor */
size_t offset;
/* Loaded hunk number */
int32_t hunknum;
/* Loaded hunk */
uint8_t *hunkmem;
};
typedef struct metadata {
char type[64];
char subtype[32];
char pgtype[32];
char pgsub[32];
uint32_t frame_offset;
uint32_t frames;
uint32_t pad;
uint32_t extra;
uint32_t pregap;
uint32_t postgap;
uint32_t track;
} metadata_t;
static uint32_t padding_frames(uint32_t frames)
{
return ((frames + TRACK_PAD - 1) & ~(TRACK_PAD - 1)) - frames;
}
static bool
chdstream_get_meta(chd_file *chd, int idx, metadata_t *md)
{
char meta[256];
uint32_t meta_size = 0;
chd_error err;
memset(md, 0, sizeof(*md));
err = chd_get_metadata(chd, CDROM_TRACK_METADATA2_TAG, idx, meta,
sizeof(meta), &meta_size, NULL, NULL);
if (err == CHDERR_NONE)
{
sscanf(meta, CDROM_TRACK_METADATA2_FORMAT,
&md->track, md->type,
md->subtype, &md->frames, &md->pregap,
md->pgtype, md->pgsub,
&md->postgap);
md->extra = padding_frames(md->frames);
return true;
}
err = chd_get_metadata(chd, CDROM_TRACK_METADATA_TAG, idx, meta,
sizeof(meta), &meta_size, NULL, NULL);
if (err == CHDERR_NONE)
{
sscanf(meta, CDROM_TRACK_METADATA_FORMAT, &md->track, md->type,
md->subtype, &md->frames);
md->extra = padding_frames(md->frames);
return true;
}
err = chd_get_metadata(chd, GDROM_TRACK_METADATA_TAG, idx, meta,
sizeof(meta), &meta_size, NULL, NULL);
if (err == CHDERR_NONE)
{
sscanf(meta, GDROM_TRACK_METADATA_FORMAT, &md->track, md->type,
md->subtype, &md->frames, &md->pad, &md->pregap, md->pgtype,
md->pgsub, &md->postgap);
md->extra = padding_frames(md->frames);
return true;
}
return false;
}
static bool
chdstream_find_track_number(chd_file *fd, int32_t track, metadata_t *meta)
{
uint32_t i;
uint32_t frame_offset = 0;
for (i = 0; true; ++i)
{
if (!chdstream_get_meta(fd, i, meta))
return false;
if (track == meta->track)
{
meta->frame_offset = frame_offset;
return true;
}
frame_offset += meta->frames + meta->extra;
}
}
static bool
chdstream_find_special_track(chd_file *fd, int32_t track, metadata_t *meta)
{
int32_t i;
metadata_t iter;
int32_t largest_track = 0;
uint32_t largest_size = 0;
for (i = 1; true; ++i)
{
if (!chdstream_find_track_number(fd, i, &iter))
{
if (track == CHDSTREAM_TRACK_LAST && i > 1)
{
*meta = iter;
return true;
}
else if (track == CHDSTREAM_TRACK_PRIMARY && largest_track != 0)
return chdstream_find_track_number(fd, largest_track, meta);
}
switch (track)
{
case CHDSTREAM_TRACK_FIRST_DATA:
if (strcmp(iter.type, "AUDIO"))
{
*meta = iter;
return true;
}
break;
case CHDSTREAM_TRACK_PRIMARY:
if (strcmp(iter.type, "AUDIO") && iter.frames > largest_size)
{
largest_size = iter.frames;
largest_track = iter.track;
}
break;
default:
break;
}
}
}
static bool
chdstream_find_track(chd_file *fd, int32_t track, metadata_t *meta)
{
if (track < 0)
return chdstream_find_special_track(fd, track, meta);
return chdstream_find_track_number(fd, track, meta);
}
chdstream_t *chdstream_open(const char *path, int32_t track)
{
metadata_t meta;
uint32_t pregap = 0;
const chd_header *hd = NULL;
chdstream_t *stream = NULL;
chd_file *chd = NULL;
chd_error err = chd_open(path, CHD_OPEN_READ, NULL, &chd);
if (err != CHDERR_NONE)
goto error;
if (!chdstream_find_track(chd, track, &meta))
goto error;
stream = (chdstream_t*)calloc(1, sizeof(*stream));
if (!stream)
goto error;
hd = chd_get_header(chd);
stream->hunkmem = (uint8_t*)malloc(hd->hunkbytes);
if (!stream->hunkmem)
goto error;
if (!strcmp(meta.type, "MODE1_RAW"))
{
stream->frame_size = SECTOR_SIZE;
stream->frame_offset = 0;
}
else if (!strcmp(meta.type, "MODE2_RAW"))
{
stream->frame_size = SECTOR_SIZE;
stream->frame_offset = 0;
}
else if (!strcmp(meta.type, "AUDIO"))
{
stream->frame_size = SECTOR_SIZE;
stream->frame_offset = 0;
stream->swab = true;
}
else
{
stream->frame_size = hd->unitbytes;
stream->frame_offset = 0;
}
/* Only include pregap data if it was in the track file */
if (!strcmp(meta.type, meta.pgtype))
pregap = meta.pregap;
else
pregap = 0;
stream->chd = chd;
stream->frames_per_hunk = hd->hunkbytes / hd->unitbytes;
stream->track_frame = meta.frame_offset;
stream->track_start = (size_t) pregap * stream->frame_size;
stream->track_end = stream->track_start +
(size_t) meta.frames * stream->frame_size;
stream->offset = 0;
stream->hunknum = -1;
return stream;
error:
chdstream_close(stream);
if (chd)
chd_close(chd);
return NULL;
}
void chdstream_close(chdstream_t *stream)
{
if (stream)
{
if (stream->hunkmem)
free(stream->hunkmem);
if (stream->chd)
chd_close(stream->chd);
free(stream);
}
}
static bool
chdstream_load_hunk(chdstream_t *stream, uint32_t hunknum)
{
chd_error err;
uint16_t *array;
uint32_t i;
uint32_t count;
if (hunknum == stream->hunknum)
return true;
err = chd_read(stream->chd, hunknum, stream->hunkmem);
if (err != CHDERR_NONE)
return false;
if (stream->swab)
{
count = chd_get_header(stream->chd)->hunkbytes / 2;
array = (uint16_t*) stream->hunkmem;
for (i = 0; i < count; ++i)
array[i] = SWAP16(array[i]);
}
stream->hunknum = hunknum;
return true;
}
ssize_t chdstream_read(chdstream_t *stream, void *data, size_t bytes)
{
size_t end;
uint32_t frame_offset;
uint32_t hunk_offset;
uint32_t chd_frame;
uint32_t hunk;
uint32_t amount;
size_t data_offset = 0;
const chd_header *hd = chd_get_header(stream->chd);
uint8_t *out = (uint8_t*)data;
if (stream->track_end - stream->offset < bytes)
bytes = stream->track_end - stream->offset;
end = stream->offset + bytes;
while (stream->offset < end)
{
frame_offset = stream->offset % stream->frame_size;
amount = stream->frame_size - frame_offset;
if (amount > end - stream->offset)
amount = end - stream->offset;
/* In pregap */
if (stream->offset < stream->track_start)
memset(out + data_offset, 0, amount);
else
{
chd_frame = stream->track_frame +
(stream->offset - stream->track_start) / stream->frame_size;
hunk = chd_frame / stream->frames_per_hunk;
hunk_offset = (chd_frame % stream->frames_per_hunk) * hd->unitbytes;
if (!chdstream_load_hunk(stream, hunk))
{
return -1;
}
memcpy(out + data_offset,
stream->hunkmem + frame_offset
+ hunk_offset + stream->frame_offset, amount);
}
data_offset += amount;
stream->offset += amount;
}
return bytes;
}
int chdstream_getc(chdstream_t *stream)
{
char c = 0;
if (chdstream_read(stream, &c, sizeof(c) != sizeof(c)))
return EOF;
return c;
}
char *chdstream_gets(chdstream_t *stream, char *buffer, size_t len)
{
int c;
size_t offset = 0;
while (offset < len && (c = chdstream_getc(stream)) != EOF)
buffer[offset++] = c;
if (offset < len)
buffer[offset] = '\0';
return buffer;
}
size_t chdstream_tell(chdstream_t *stream)
{
return stream->offset;
}
void chdstream_rewind(chdstream_t *stream)
{
stream->offset = 0;
}
int chdstream_seek(chdstream_t *stream, ssize_t offset, int whence)
{
ssize_t new_offset;
switch (whence)
{
case SEEK_SET:
new_offset = offset;
break;
case SEEK_CUR:
new_offset = stream->offset + offset;
break;
case SEEK_END:
new_offset = stream->track_end + offset;
break;
default:
return -1;
}
if (new_offset < 0)
return -1;
if (new_offset > stream->track_end)
new_offset = stream->track_end;
stream->offset = new_offset;
return 0;
}