fte/quakespasm
2
0
Fork 0
mirror of https://github.com/Shpoike/Quakespasm.git synced 2025-04-20 09:55:38 +00:00
Code Issues Projects Releases Packages Wiki Activity

snd_mp3.c: removed unnecessary file rewind calls in tag detection code.

Browse source 
git-svn-id: svn://svn.code.sf.net/p/quakespasm/code/trunk/quakespasm@1657 af15c1b1-3010-417e-b628-4374ebc0bcbd
This commit is contained in:
Ozkan Sezer 2019-12-12 08:23:12 +00:00
parent 3b4a07ca87
commit b2bf251a32
1 changed files with 33 additions and 44 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

77
Quake/snd_mp3.c
View file

@ -61,9 +61,10 @@ typedef struct _mp3_priv_t
} mp3_priv_t;
/* TAG HANDLING: put together by O. Sezer <sezero@users.sourceforge.net>
* using public specs, put into public domain. *************************/
/* TAG HANDLING:
* put together by O.Sezer <sezero@users.sourceforge.net> using public specs,
* put into public domain.
*/
static inline qboolean tag_is_id3v1(const unsigned char *data, size_t length) {
/* http://id3.org/ID3v1 : 3 bytes "TAG" identifier and 125 bytes tag data */
if (length < 3 || memcmp(data,"TAG",3) != 0) {
@ -148,7 +149,6 @@ static inline long get_lyrics3v1_len(snd_stream_t *stream, unsigned char *buf) {
len = (stream->fh.length > 5109)? 5109 : stream->fh.length;
FS_fseek(&stream->fh, -len, SEEK_END);
FS_fread(buf, 1, (len -= 9), &stream->fh); /* exclude footer */
FS_rewind(&stream->fh);
/* strstr() won't work here. */
for (i = len - 11, p = (const char*)buf; i >= 0; --i, ++p) {
if (memcmp(p, "LYRICSBEGIN", 11) == 0)
@ -169,63 +169,55 @@ static inline qboolean verify_lyrics3v2(const unsigned char *data, size_t length
return false;
}
static int skip_tags_first(snd_stream_t *stream, unsigned char *buf, size_t bufsize)
static int mp3_skiptags(snd_stream_t *stream, unsigned char *buf, size_t bufsize)
{
long len; size_t readsize;
int rc = -1;
readsize = FS_fread(buf, 1, bufsize, &stream->fh);
if (!readsize || FS_ferror(&stream->fh))
return -1;
if (!readsize || FS_ferror(&stream->fh)) goto fail;
/* ID3v2 tag is at the start */
if (tag_is_id3v2(buf, readsize)) {
len = get_id3v2_len(buf, (long)readsize);
if (len >= stream->fh.length) return -1;
/* hack the fshandle_t start pos and length members */
if (len >= stream->fh.length) goto fail;
stream->fh.start += len;
stream->fh.length -= len;
FS_rewind(&stream->fh);
Con_DPrintf("MP3: skipped %ld bytes ID3v2 tag\n", len);
}
/* APE tag _might_ be at the start (discouraged
* but not forbidden, either.) read the header. */
else if (tag_is_apetag(buf, readsize)) {
len = get_ape_len(buf);
if (len >= stream->fh.length) return -1;
/* hack the fshandle_t start pos and length members */
if (len >= stream->fh.length) goto fail;
stream->fh.start += len;
stream->fh.length -= len;
FS_rewind(&stream->fh);
Con_DPrintf("MP3: skipped %ld bytes APE tag\n", len);
}
/* ID3v1 tag is at the end */
if (stream->fh.length < 128) goto ape;
FS_fseek(&stream->fh, -128, SEEK_END);
readsize = FS_fread(buf, 1, 128, &stream->fh);
FS_rewind(&stream->fh);
if (readsize != 128) return -1;
if (tag_is_id3v1(buf, 128)) {
/* hack fshandle_t->length */
stream->fh.length -= 128;
Con_DPrintf("MP3: skipped %ld bytes ID3v1 tag\n", 128L);
/* FIXME: handle possible double-ID3v1 tags? */
if (stream->fh.length >= 128) {
FS_fseek(&stream->fh, -128, SEEK_END);
readsize = FS_fread(buf, 1, 128, &stream->fh);
if (readsize != 128) goto fail;
if (tag_is_id3v1(buf, 128)) {
stream->fh.length -= 128;
Con_DPrintf("MP3: skipped %ld bytes ID3v1 tag\n", 128L);
/* FIXME: handle possible double-ID3v1 tags? */
}
}
/* do we know whether ape or lyrics3 is the first?
* well, we don't: we need to handle that later... */
ape: /* APE tag may be at the end: read the footer */
/* APE tag may be at the end: read the footer */
if (stream->fh.length >= 32) {
FS_fseek(&stream->fh, -32, SEEK_END);
readsize = FS_fread(buf, 1, 32, &stream->fh);
FS_rewind(&stream->fh);
if (readsize != 32) return -1;
if (readsize != 32) goto fail;
if (tag_is_apetag(buf, 32)) {
len = get_ape_len(buf);
if (len >= stream->fh.length) return -1;
/* hack fshandle_t->length */
if (len >= stream->fh.length) goto fail;
stream->fh.length -= len;
Con_DPrintf("MP3: skipped %ld bytes APE tag\n", len);
}
@ -234,32 +226,31 @@ static int skip_tags_first(snd_stream_t *stream, unsigned char *buf, size_t bufs
if (stream->fh.length >= 15) {
FS_fseek(&stream->fh, -15, SEEK_END);
readsize = FS_fread(buf, 1, 15, &stream->fh);
FS_rewind(&stream->fh);
if (readsize != 15) return -1;
if (readsize != 15) goto fail;
len = is_lyrics3tag(buf, 15);
if (len == 2) {
len = get_lyrics3v2_len(buf, 6);
if (len >= stream->fh.length) return -1;
if (len < 15) return -1;
if (len >= stream->fh.length) goto fail;
if (len < 15) goto fail;
FS_fseek(&stream->fh, -len, SEEK_END);
readsize = FS_fread(buf, 1, 11, &stream->fh);
FS_rewind(&stream->fh);
if (readsize != 11) return -1;
if (!verify_lyrics3v2(buf, 11)) return -1;
/* hack fshandle_t->length */
if (readsize != 11) goto fail;
if (!verify_lyrics3v2(buf, 11)) goto fail;
stream->fh.length -= len;
Con_DPrintf("MP3: skipped %ld bytes Lyrics3 tag\n", len);
}
else if (len == 1) {
len = get_lyrics3v1_len(stream, buf);
if (len < 0) return -1;
/* hack fshandle_t->length */
if (len < 0) goto fail;
stream->fh.length -= len;
Con_DPrintf("MP3: skipped %ld bytes Lyrics3 tag\n", len);
}
}
return (stream->fh.length > 0)? 0: -1;
rc = 0;
fail:
FS_rewind(&stream->fh);
return (stream->fh.length > 0)? rc : -1;
}
/* (Re)fill the stream buffer that is to be decoded. If any data
@ -301,8 +292,7 @@ static int mp3_startread(snd_stream_t *stream)
mp3_priv_t *p = (mp3_priv_t *) stream->priv;
size_t ReadSize;
/* skip tags known to be at start or end and adjust the file */
if (skip_tags_first(stream, p->mp3_buffer, MP3_BUFFER_SIZE) < 0)
if (mp3_skiptags(stream, p->mp3_buffer, MP3_BUFFER_SIZE) < 0)
return -1;
mad_stream_init(&p->Stream);
@ -321,8 +311,7 @@ static int mp3_startread(snd_stream_t *stream)
mad_stream_buffer(&p->Stream, p->mp3_buffer, ReadSize);
/* Find a valid frame before starting up. This makes sure
* that we have a valid MP3 and also skips past ID3v2 tags
* at the beginning of the audio file.
* that we have a valid MP3.
*/
p->Stream.error = MAD_ERROR_NONE;
while (mad_frame_decode(&p->Frame,&p->Stream))