cue_parser: new line based CUE sheet parser

To replace libcue, the unmaintained and crashy library.

1 files changed, 327 insertions, 0 deletions

diff --git a/src/cue/cue_parser.c b/src/cue/cue_parser.c
new file mode 100644
index 000000000..034d4a1f9
--- /dev/null
+++ b/src/cue/cue_parser.c
@@ -0,0 +1,327 @@
+/*
+ * Copyright (C) 2003-2011 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "cue_parser.h"
+#include "string_util.h"
+#include "song.h"
+#include "tag.h"
+
+#include <assert.h>
+#include <stdlib.h>
+
+struct cue_parser {
+	enum {
+		/**
+		 * Parsing the CUE header.
+		 */
+		HEADER,
+
+		/**
+		 * Parsing a "FILE ... WAVE".
+		 */
+		WAVE,
+
+		/**
+		 * Ignore everything until the next "FILE".
+		 */
+		IGNORE_FILE,
+
+		/**
+		 * Parsing a "TRACK ... AUDIO".
+		 */
+		TRACK,
+
+		/**
+		 * Ignore everything until the next "TRACK".
+		 */
+		IGNORE_TRACK,
+	} state;
+
+	struct tag *tag;
+
+	char *filename;
+
+	struct song *current, *previous, *finished;
+
+	bool last_updated;
+};
+
+struct cue_parser *
+cue_parser_new(void)
+{
+	struct cue_parser *parser = g_new(struct cue_parser, 1);
+	parser->state = HEADER;
+	parser->tag = tag_new();
+	parser->filename = NULL;
+	parser->current = NULL;
+	parser->previous = NULL;
+	parser->finished = NULL;
+	return parser;
+}
+
+void
+cue_parser_free(struct cue_parser *parser)
+{
+	tag_free(parser->tag);
+	g_free(parser->filename);
+
+	if (parser->current != NULL)
+		song_free(parser->current);
+
+	if (parser->finished != NULL)
+		song_free(parser->finished);
+
+	g_free(parser);
+}
+
+static const char *
+cue_next_word(char *p, char **pp)
+{
+	assert(p >= *pp);
+	assert(!g_ascii_isspace(*p));
+
+	const char *word = p;
+	while (*p != 0 && !g_ascii_isspace(*p))
+		++p;
+
+	*p = 0;
+	*pp = p + 1;
+	return word;
+}
+
+static const char *
+cue_next_quoted(char *p, char **pp)
+{
+	assert(p >= *pp);
+	assert(p[-1] == '"');
+
+	char *end = strchr(p, '"');
+	if (end == NULL) {
+		/* syntax error - ignore it silently */
+		*pp = p + strlen(p);
+		return p;
+	}
+
+	*end = 0;
+	*pp = end + 1;
+
+	return p;
+}
+
+static const char *
+cue_next_token(char **pp)
+{
+	char *p = strchug_fast(*pp);
+	if (*p == 0)
+		return NULL;
+
+	return cue_next_word(p, pp);
+}
+
+static const char *
+cue_next_value(char **pp)
+{
+	char *p = strchug_fast(*pp);
+	if (*p == 0)
+		return NULL;
+
+	if (*p == '"')
+		return cue_next_quoted(p + 1, pp);
+	else
+		return cue_next_word(p, pp);
+}
+
+static void
+cue_add_tag(struct tag *tag, enum tag_type type, char *p)
+{
+	const char *value = cue_next_value(&p);
+	if (value != NULL)
+		tag_add_item(tag, type, value);
+
+}
+
+static void
+cue_parse_rem(char *p, struct tag *tag)
+{
+	const char *type = cue_next_token(&p);
+	if (type == NULL)
+		return;
+
+	enum tag_type type2 = tag_name_parse_i(type);
+	if (type2 != TAG_NUM_OF_ITEM_TYPES)
+		cue_add_tag(tag, type2, p);
+}
+
+static struct tag *
+cue_current_tag(struct cue_parser *parser)
+{
+	if (parser->state == HEADER)
+		return parser->tag;
+	else if (parser->state == TRACK)
+		return parser->current->tag;
+	else
+		return NULL;
+}
+
+static int
+cue_parse_position(const char *p)
+{
+	char *endptr;
+	unsigned long minutes = strtoul(p, &endptr, 10);
+	if (endptr == p || *endptr != ':')
+		return -1;
+
+	p = endptr + 1;
+	unsigned long seconds = strtoul(p, &endptr, 10);
+	if (endptr == p || *endptr != ':')
+		return -1;
+
+	p = endptr + 1;
+	unsigned long frames = strtoul(p, &endptr, 10);
+	if (endptr == p || *endptr != 0)
+		return -1;
+
+	return minutes * 60000 + seconds * 1000 + frames * 1000 / 75;
+}
+
+static void
+cue_parser_feed2(struct cue_parser *parser, char *p)
+{
+	assert(parser != NULL);
+	assert(p != NULL);
+
+	const char *command = cue_next_token(&p);
+	if (command == NULL)
+		return;
+
+	if (strcmp(command, "REM") == 0) {
+		struct tag *tag = cue_current_tag(parser);
+		if (tag != NULL)
+			cue_parse_rem(p, tag);
+	} else if (strcmp(command, "PERFORMER") == 0) {
+		struct tag *tag = cue_current_tag(parser);
+		if (tag != NULL)
+			cue_add_tag(tag, TAG_PERFORMER, p);
+	} else if (strcmp(command, "TITLE") == 0) {
+		if (parser->state == HEADER)
+			cue_add_tag(parser->tag, TAG_ALBUM, p);
+		else if (parser->state == TRACK)
+			cue_add_tag(parser->current->tag, TAG_TITLE, p);
+	} else if (strcmp(command, "FILE") == 0) {
+		cue_parser_finish(parser);
+
+		const char *filename = cue_next_value(&p);
+		if (filename == NULL)
+			return;
+
+		const char *type = cue_next_token(&p);
+		if (type == NULL)
+			return;
+
+		if (strcmp(type, "WAVE") != 0) {
+			parser->state = IGNORE_FILE;
+			return;
+		}
+
+		parser->state = WAVE;
+		g_free(parser->filename);
+		parser->filename = g_strdup(filename);
+	} else if (parser->state == IGNORE_FILE) {
+		return;
+	} else if (strcmp(command, "TRACK") == 0) {
+		cue_parser_finish(parser);
+
+		const char *nr = cue_next_token(&p);
+		if (nr == NULL)
+			return;
+
+		const char *type = cue_next_token(&p);
+		if (type == NULL)
+			return;
+
+		if (strcmp(type, "AUDIO") != 0) {
+			parser->state = IGNORE_TRACK;
+			return;
+		}
+
+		parser->state = TRACK;
+		parser->current = song_remote_new(parser->filename);
+		assert(parser->current->tag == NULL);
+		parser->current->tag = tag_dup(parser->tag);
+		tag_add_item(parser->current->tag, TAG_TRACK, nr);
+		parser->last_updated = false;
+	} else if (parser->state == IGNORE_TRACK) {
+		return;
+	} else if (parser->state == TRACK && strcmp(command, "INDEX") == 0) {
+		const char *nr = cue_next_token(&p);
+		if (nr == NULL)
+			return;
+
+		const char *position = cue_next_token(&p);
+		if (position == NULL)
+			return;
+
+		int position_ms = cue_parse_position(position);
+		if (position_ms < 0)
+			return;
+
+		if (!parser->last_updated && parser->previous != NULL &&
+		    parser->previous->start_ms < (unsigned)position_ms) {
+			parser->last_updated = true;
+			parser->previous->end_ms = position_ms;
+			parser->previous->tag->time =
+				(parser->previous->end_ms - parser->previous->start_ms + 500) / 1000;
+		}
+
+		parser->current->start_ms = position_ms;
+	}
+}
+
+void
+cue_parser_feed(struct cue_parser *parser, const char *line)
+{
+	assert(parser != NULL);
+	assert(line != NULL);
+
+	char *allocated = g_strdup(line);
+	cue_parser_feed2(parser, allocated);
+	g_free(allocated);
+}
+
+void
+cue_parser_finish(struct cue_parser *parser)
+{
+	if (parser->finished != NULL)
+		song_free(parser->finished);
+
+	parser->finished = parser->previous;
+	parser->previous = parser->current;
+	parser->current = NULL;
+}
+
+struct song *
+cue_parser_get(struct cue_parser *parser)
+{
+	assert(parser != NULL);
+
+	struct song *song = parser->finished;
+	parser->finished = NULL;
+	return song;
+}