add support for parsing ape tags in musepack files

git-svn-id: https://svn.musicpd.org/mpd/trunk@3030 09075e82-0dd4-0310-85a5-a0d7c8717e4f

TODO

@@ -12,8 +12,6 @@
 	*) Handle mp1 and mp2 files (including files with mp3 suffixes) 
 	*) add support for playing aac streams (gee, thanks icecast)
 	*) parsing of lame tags (including getting replaygain and gapless info)
-	*) implement apev2 and id3v1 tag reader from xmms-musepack plugin
-	*) only use libid3tag for id3v2 tags, use internal impl for id3v1 tags
 
 *) aduio output
 	*) allowing "pausing" of audio output devices

src/inputPlugins/mpc_plugin.c

@@ -47,7 +47,7 @@ static mpc_int32_t mpc_read_cb(void * vdata, void * ptr, mpc_int32_t size) {
         while(1) {
 	        ret = readFromInputStream(data->inStream, ptr, 1, size);
                 if(ret == 0 && !inputStreamAtEOF(data->inStream) && 
-                                !data->dc->stop) 
+                                (data->dc && !data->dc->stop)) 
                 {
                         my_usleep(10000);
                 }
@@ -272,17 +272,50 @@ static int mpc_decode(OutputBuffer * cb, DecoderControl * dc,
 	return 0;
 }
 
+static float mpcGetTime(char * file) {
+	InputStream inStream;
+	float time = -1;
+	
+	mpc_reader reader;
+	mpc_streaminfo info;
+	MpcCallbackData data;
+
+        data.inStream = &inStream;
+        data.dc = NULL;
+
+	reader.read = mpc_read_cb;
+	reader.seek = mpc_seek_cb;
+	reader.tell = mpc_tell_cb;
+	reader.get_size = mpc_getsize_cb;
+	reader.canseek = mpc_canseek_cb;
+	reader.data = &data;
+
+	mpc_streaminfo_init(&info);
+
+	if(openInputStream(&inStream, file) < 0) return -1;
+	
+	if(mpc_streaminfo_read(&info, &reader) != ERROR_CODE_OK) {
+		closeInputStream(&inStream);
+		return -1;
+	}
+
+	time = mpc_streaminfo_get_length(&info);
+
+	closeInputStream(&inStream);
+
+	return time;
+}
+
 static MpdTag * mpcTagDup(char * file) {
 	MpdTag * ret = NULL;
-	FILE * fp;
+	float time = mpcGetTime(file);
 
-	fp = fopen(file,"r"); 
-	if(!fp) return NULL;
-
-	/* get tag info here */
+	if(time < 0) return NULL;
 
+	ret = apeDup(file);
+	if(!ret) ret = id3Dup(file);
 	if(!ret) ret = newMpdTag();
-	ret->time = 0;
+	ret->time = time;
 
 	return ret;	
 }

src/tag.c

@@ -217,6 +217,113 @@ MpdTag * id3Dup(char * file) {
 	return ret;	
 }
 
+MpdTag * apeDup(char * file) {
+	MpdTag * ret = NULL;
+	FILE * fp = NULL;
+	int tagCount;
+	unsigned char * buffer = NULL;
+	unsigned char * p;
+	int tagLen;
+	int size;
+	unsigned long flags;
+	int i;
+	unsigned char * key;
+
+	struct {
+		unsigned char id[8];
+		unsigned char version[4];
+		unsigned char length[4];
+		unsigned char tagCount[4];
+		unsigned char flags[4];
+		unsigned char reserved[8];
+	} footer;
+
+	char * apeItems[7] =
+	{
+		"title",
+		"artist",
+		"album",
+		"comment",
+		"genre",
+		"track",
+		"year"
+	};
+
+	int tagItems[7] =
+	{
+		TAG_ITEM_TITLE,
+		TAG_ITEM_ARTIST,
+		TAG_ITEM_ALBUM,
+		TAG_ITEM_COMMENT,
+		TAG_ITEM_GENRE,
+		TAG_ITEM_TRACK,
+		TAG_ITEM_DATE,
+	};
+
+	fp = fopen(file, "r");
+	if(!fp) return NULL;
+
+	/* determine if file has an apeV2 tag */
+	if(fseek(fp, 0, SEEK_END)) goto fail;
+	size = ftell(fp);
+	if(fseek(fp, size-sizeof(footer), SEEK_SET)) goto fail;
+	if(fread(&footer, 1, sizeof(footer), fp) != sizeof(footer)) goto fail;
+	if(memcmp(footer.id, "APETAGEX", sizeof(footer.id)) != 0) goto fail;
+	if(readLEuint32(footer.version) != 2000) goto fail;
+
+	/* find begining of ape tag */
+	tagLen = readLEuint32(footer.length);
+	if(tagLen < sizeof(footer)) goto fail;
+	if(fseek(fp, size-tagLen, SEEK_SET)) goto fail;
+
+	/* read tag into buffer */
+	tagLen -= sizeof(footer);
+	buffer = malloc(tagLen);
+	if(fread(buffer, 1, tagLen, fp) != tagLen) goto fail;
+
+	/* read tags */
+	tagCount = readLEuint32(footer.tagCount);
+	p = buffer;
+	while(tagCount-- && tagLen > 10) {
+		size = readLEuint32(p);
+		p += 4;
+		tagLen -= 4;
+		flags = readLEuint32(p);
+		p += 4;
+		tagLen -= 4;
+
+		/* get the key */
+		key = p;
+		while(tagLen-size > 0 && *p != '\0') {
+			p++;
+			tagLen--;
+		}
+		p++;
+		tagLen--;
+
+		/* get the value */
+		if(tagLen-size < 0) goto fail;
+
+		/* we only care about utf-8 text tags */
+		if(!(flags & (0x3 << 1))) {
+			for(i = 0; i < 7; i++) {
+				if(strcasecmp(key, apeItems[i]) == 0) {
+					if(!ret) ret = newMpdTag();
+					addItemToMpdTagWithLen(
+						ret, tagItems[i], p, size);
+				}
+			}
+		}
+		p += size;
+		tagLen -= size;
+	}
+	
+fail:
+	if(fp) fclose(fp);
+	if(buffer) free(buffer);
+	return ret;
+}
+
 MpdTag * newMpdTag() {
 	MpdTag * ret = malloc(sizeof(MpdTag));
 	ret->items = NULL;

src/tag.h

@@ -64,6 +64,8 @@ typedef struct _MpdTag {
 MpdTag * parseId3Tag(struct id3_tag *);
 #endif
 
+MpdTag * apeDup(char * file);
+
 MpdTag * id3Dup(char * file);
 
 MpdTag * newMpdTag();

src/utils.c

@@ -92,3 +92,11 @@ char * appendToString(char * dest, const char * src) {
                                                                                 
         return dest;
 }
+
+unsigned long readLEuint32(const unsigned char *p)
+{
+	return ((unsigned long) p[0] << 0) |
+        	((unsigned long) p[1] << 8) |
+        	((unsigned long) p[2] << 16) | ((unsigned long) p[3] << 24);
+}
+

src/utils.h

@@ -35,4 +35,6 @@ int ipv6Supported();
 
 char * appendToString(char * dest, const char * src);
 
+unsigned long readLEuint32(const unsigned char * p);
+
 #endif