X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=flac_afh.c;h=2e2842b183c91bfbe06ec2de0616fb52872ba4f4;hp=d2f256dc152a8e9547968b5f30ece5cff381754c;hb=5e8d8a8eea6de9459ebdf4498f9f061c84bfa63a;hpb=9c5fbc5dd8b53604d7e73fb6714ee2b5e3458866

diff --git a/flac_afh.c b/flac_afh.c
index d2f256dc..2e2842b1 100644
--- a/flac_afh.c
+++ b/flac_afh.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2011-2013 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -14,9 +14,10 @@
 #include "error.h"
 #include "afh.h"
 #include "string.h"
+#include "fd.h"
 
 struct private_flac_afh_data {
-	char *map;
+	const char *map;
 	size_t map_bytes;
 	size_t fpos;
 	struct afh_info *afhi;
@@ -80,7 +81,7 @@ static FLAC__int64 meta_tell_cb(FLAC__IOHandle handle)
 static int meta_eof_cb(FLAC__IOHandle handle)
 {
 	struct private_flac_afh_data *pfad = handle;
-	return pfad->fpos == pfad->map_bytes - 1;
+	return pfad->fpos == pfad->map_bytes;
 }
 
 static int meta_close_cb(FLAC__IOHandle __a_unused handle)
@@ -88,6 +89,15 @@ static int meta_close_cb(FLAC__IOHandle __a_unused handle)
 	return 0;
 }
 
+static const FLAC__IOCallbacks meta_callbacks = {
+	.read = meta_read_cb,
+	.write = NULL,
+	.seek = meta_seek_cb,
+	.tell = meta_tell_cb,
+	.eof = meta_eof_cb,
+	.close = meta_close_cb
+};
+
 static void free_tags(struct taginfo *tags)
 {
 	freep(&tags->artist);
@@ -131,22 +141,95 @@ static void flac_read_vorbis_comments(FLAC__StreamMetadata_VorbisComment *vc,
 	}
 }
 
-static int flac_read_meta(struct private_flac_afh_data *pfad)
+/*
+ * FLAC__metadata_object_vorbiscomment_replace_comment() is buggy in some
+ * libFLAC versions (see commit e95399c1 in the flac git repository). Hence we
+ * use delete and add as a workaround.
+ */
+static int flac_replace_vorbis_comment(FLAC__StreamMetadata *b,
+		const char *tag, const char* val)
 {
+	FLAC__bool ok;
+	FLAC__StreamMetadata_VorbisComment_Entry entry;
 	int ret;
-	FLAC__IOCallbacks meta_callbacks = {
-		.read = meta_read_cb,
-		.write = NULL,
-		.seek = meta_seek_cb,
-		.tell = meta_tell_cb,
-		.eof = meta_eof_cb,
-		.close = meta_close_cb
-	};
+
+	PARA_INFO_LOG("replacing %s\n", tag);
+	ret = FLAC__metadata_object_vorbiscomment_remove_entries_matching(
+		b, tag);
+	if (ret < 0)
+		return -E_FLAC_REPLACE_COMMENT;
+	ok = FLAC__metadata_object_vorbiscomment_entry_from_name_value_pair(
+		&entry, tag, val? val : "");
+	if (!ok)
+		return -E_FLAC_REPLACE_COMMENT;
+	ok = FLAC__metadata_object_vorbiscomment_append_comment(b, entry,
+		false /* no copy */);
+	if (!ok) {
+		free(entry.entry);
+		return -E_FLAC_REPLACE_COMMENT;
+	}
+	return 1;
+}
+
+static int flac_replace_vorbis_comments(FLAC__Metadata_Chain *chain,
+		FLAC__StreamMetadata *b, struct taginfo *tags)
+{
+	FLAC__bool ok;
+	int ret;
+
+	ret = flac_replace_vorbis_comment(b, "artist", tags->artist);
+	if (ret < 0)
+		return ret;
+	ret = flac_replace_vorbis_comment(b, "title", tags->title);
+	if (ret < 0)
+		return ret;
+	ret = flac_replace_vorbis_comment(b, "album", tags->album);
+	if (ret < 0)
+		return ret;
+	ret = flac_replace_vorbis_comment(b, "year", tags->year);
+	if (ret < 0)
+		return ret;
+	ret = flac_replace_vorbis_comment(b, "comment", tags->comment);
+	if (ret < 0)
+		return ret;
+	/*
+	 * Even if padding is disabled, libflac will try to modify the original
+	 * file inplace if the metadata size has not changed. This won't work
+	 * here though, because the original file is mapped read-only. Since
+	 * there is no option to force the use of a temp file we work around
+	 * this shortcoming by adding a dummy entry which increases the size of
+	 * the meta data. If the entry already exists, we simply remove it.
+	 */
+	ok = FLAC__metadata_chain_check_if_tempfile_needed(chain,
+		false /* no padding */);
+	if (!ok) {
+		PARA_INFO_LOG("adding/removing dummy comment\n");
+		ret = FLAC__metadata_object_vorbiscomment_remove_entries_matching(
+			b, "comment2");
+		if (ret < 0)
+			return -E_FLAC_REPLACE_COMMENT;
+		if (ret == 0) { /* nothing was removed */
+			ret = flac_replace_vorbis_comment(b, "comment2",
+				"avoid inplace write");
+			if (ret < 0)
+				return ret;
+		}
+		assert(FLAC__metadata_chain_check_if_tempfile_needed(chain,
+			false /* no padding */));
+	}
+	return 1;
+}
+
+static int flac_init_meta(struct private_flac_afh_data *pfad,
+		FLAC__Metadata_Chain **chainp, FLAC__Metadata_Iterator **iterp)
+{
+	int ret;
+	FLAC__bool ok;
 	FLAC__Metadata_Chain *chain;
 	FLAC__Metadata_Iterator *iter;
-	FLAC__StreamMetadata_StreamInfo *info = NULL;
-	FLAC__bool ok;
 
+	*chainp = NULL;
+	*iterp = NULL;
 	chain = FLAC__metadata_chain_new();
 	if (!chain)
 		return -E_FLAC_CHAIN_ALLOC;
@@ -160,6 +243,25 @@ static int flac_read_meta(struct private_flac_afh_data *pfad)
 	if (!iter)
 		goto free_chain;
 	FLAC__metadata_iterator_init(iter, chain);
+	*iterp = iter;
+	*chainp = chain;
+	return 1;
+free_chain:
+	FLAC__metadata_chain_delete(chain);
+	return ret;
+}
+
+static int flac_read_meta(struct private_flac_afh_data *pfad)
+{
+	int ret;
+	FLAC__Metadata_Chain *chain;
+	FLAC__Metadata_Iterator *iter;
+	FLAC__StreamMetadata_StreamInfo *info = NULL;
+	FLAC__bool ok;
+
+	ret = flac_init_meta(pfad, &chain, &iter);
+	if (ret < 0)
+		return ret;
 	for (;;) {
 		FLAC__StreamMetadata *b;
 		b = FLAC__metadata_iterator_get_block(iter);
@@ -184,7 +286,6 @@ static int flac_read_meta(struct private_flac_afh_data *pfad)
 	ret = info? 0: -E_FLAC_STREAMINFO;
 free_iter:
 	FLAC__metadata_iterator_delete(iter);
-free_chain:
 	FLAC__metadata_chain_delete(chain);
 	if (ret < 0)
 		free_tags(&pfad->afhi->tags);
@@ -215,7 +316,7 @@ static FLAC__StreamDecoderTellStatus tell_cb(
 	return FLAC__STREAM_DECODER_TELL_STATUS_OK;
 }
 
-/* libflac insits on this callback being present. */
+/* libflac insists on this callback being present. */
 static FLAC__StreamDecoderWriteStatus write_cb(
 		__a_unused const FLAC__StreamDecoder *decoder,
 		__a_unused const FLAC__Frame *frame,
@@ -332,7 +433,89 @@ static int flac_get_file_info(char *map, size_t map_bytes, __a_unused int fd,
 	return 1;
 }
 
-static const char* flac_suffixes[] = {"flac", NULL};
+static size_t temp_write_cb(const void *ptr, size_t size, size_t nmemb,
+	FLAC__IOHandle handle)
+{
+	int ret, fd = *(int *)handle;
+	size_t n = size * nmemb; /* FIXME: possible overflow */
+
+	ret = write_all(fd, ptr, n);
+
+	/*
+	 * libflac expects POSIX semantics: If an error occurs, or the end of
+	 * the file is reached, the return value is a short item count or zero.
+	 */
+	if (ret < 0) {
+		PARA_ERROR_LOG("%s\n", para_strerror(-ret));
+		return 0;
+	}
+	return nmemb;
+}
+
+/* only the write callback needs to be supplied for writing the temp file. */
+static const FLAC__IOCallbacks temp_callbacks = {
+	.write = temp_write_cb,
+};
+
+static int flac_write_chain(FLAC__Metadata_Chain *chain,
+		struct private_flac_afh_data *pfad, int fd)
+{
+	FLAC__bool ok;
+
+	ok = FLAC__metadata_chain_write_with_callbacks_and_tempfile(chain,
+		false /* no padding*/, pfad,
+		meta_callbacks, &fd, temp_callbacks);
+	if (!ok) {
+		FLAC__Metadata_ChainStatus st;
+		st = FLAC__metadata_chain_status(chain);
+		PARA_ERROR_LOG("chain status: %d\n", st);
+		if (st == FLAC__METADATA_CHAIN_STATUS_READ_ERROR)
+			PARA_ERROR_LOG("read error\n");
+		return -E_FLAC_WRITE_CHAIN;
+	}
+	return 1;
+}
+
+static int flac_rewrite_tags(const char *map, size_t map_bytes,
+		struct taginfo *tags, int fd, __a_unused const char *filename)
+{
+	int ret;
+	FLAC__Metadata_Chain *chain;
+	FLAC__Metadata_Iterator *iter;
+	FLAC__StreamMetadata *b = NULL;
+	FLAC__bool ok;
+	struct private_flac_afh_data *pfad = para_calloc(sizeof(*pfad));
+
+	pfad->map = map;
+	pfad->map_bytes = map_bytes;
+	pfad->fpos = 0;
+
+	ret = flac_init_meta(pfad, &chain, &iter);
+	if (ret < 0)
+		goto free_pfad;
+	for (ok = true; ok; ok = FLAC__metadata_iterator_next(iter)) {
+		b = FLAC__metadata_iterator_get_block(iter);
+		assert(b);
+		if (b->type == FLAC__METADATA_TYPE_VORBIS_COMMENT)
+			break;
+		b = NULL;
+	}
+	ret = -E_FLAC_REPLACE_COMMENT;
+	if (!b)
+		goto out;
+	ret = flac_replace_vorbis_comments(chain, b, tags);
+	if (ret < 0)
+		goto out;
+	ret = flac_write_chain(chain, pfad, fd);
+out:
+	FLAC__metadata_iterator_delete(iter);
+	FLAC__metadata_chain_delete(chain);
+free_pfad:
+	free(pfad);
+	return ret;
+}
+
+static const char * const flac_suffixes[] = {"flac", NULL};
 
 /**
  * The init function of the flac audio format handler.
@@ -343,4 +526,5 @@ void flac_afh_init(struct audio_format_handler *afh)
 {
 	afh->get_file_info = flac_get_file_info,
 	afh->suffixes = flac_suffixes;
+	afh->rewrite_tags = flac_rewrite_tags;
 }