From: Andre Noll <maan@tuebingen.mpg.de>
Date: Sat, 14 Aug 2021 15:53:59 +0000 (+0200)
Subject: mp4: Simplify and speed up metadata editing.
X-Git-Tag: v0.7.1~7^2~84
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=a4d904cc19f2b088cc1c72d9f5ce1fcb998e2dcb;p=paraslash.git

mp4: Simplify and speed up metadata editing.

Currently the aac audio format handler first calls mp4_open_meta()
to get the metadata tags, then alters the in-memory structure of the
tags according to the command line options and passes this modified
structure to mp4_meta_update() to rewrite the tags. This latter call
parses the tags again, which is unnecessary overhead.

This patch changes the signature of mp4_meta_update() to accept an
mp4 structure instead of a callback structure and uses that instead
of re-opening the file.
---

diff --git a/aac_afh.c b/aac_afh.c
index d6ff4e93..84aeaa85 100644
--- a/aac_afh.c
+++ b/aac_afh.c
@@ -256,7 +256,7 @@ static int aac_afh_rewrite_tags(const char *map, size_t mapsize,
 
 		ret = -E_MP4_META_READ;
 		if (!mp4_meta_get_by_index(mp4, i, &tag->item, &tag->value))
-			goto free_tags;
+			goto close;
 		PARA_INFO_LOG("found: %s: %s\n", tag->item, tag->value);
 		if (!strcmp(tag->item, "artist"))
 			replace_tag(tag, tags->artist, &found_artist);
@@ -280,15 +280,9 @@ static int aac_afh_rewrite_tags(const char *map, size_t mapsize,
 	if (!found_comment)
 		add_tag(&metadata, "comment", tags->comment);
 	ret = -E_MP4_META_WRITE;
-	if (!mp4_meta_update(&cb, &metadata))
-		goto free_tags;
+	if (!mp4_meta_update(mp4, &metadata))
+		goto close;
 	ret = 1;
-free_tags:
-	for (; i > 0; i--) {
-		free(metadata.tags[i - 1].item);
-		free(metadata.tags[i - 1].value);
-	}
-	free(metadata.tags);
 close:
 	mp4_close(mp4);
 	return ret;
diff --git a/mp4.c b/mp4.c
index d2a54eb2..37a700ba 100644
--- a/mp4.c
+++ b/mp4.c
@@ -1709,17 +1709,15 @@ static int32_t write_int32(struct mp4 *f, uint32_t data)
 	return write_data(f, temp, sizeof(temp));
 }
 
-int32_t mp4_meta_update(const struct mp4_callback *cb,
-		const struct mp4_metadata *data)
+int32_t mp4_meta_update(struct mp4 *f, struct mp4_metadata *meta)
 {
 	void *new_moov_data;
 	uint32_t new_moov_size;
 
-	struct mp4 *f = para_calloc(sizeof(struct mp4));
-	f->cb = cb;
+	tag_delete(&f->tags);
+	f->tags = *meta;
 	set_position(f, 0);
-	parse_atoms(f, 1);
-	if (!modify_moov(f, data, &new_moov_data, &new_moov_size)) {
+	if (!modify_moov(f, meta, &new_moov_data, &new_moov_size)) {
 		mp4_close(f);
 		return 0;
 	}
@@ -1743,8 +1741,7 @@ int32_t mp4_meta_update(const struct mp4_callback *cb,
 		write_data(f, new_moov_data, new_moov_size);
 	}
 	free(new_moov_data);
-	cb->truncate(cb->user_data);
-	mp4_close(f);
+	f->cb->truncate(f->cb->user_data);
 	return 1;
 }
 
diff --git a/mp4.h b/mp4.h
index 82bd6788..71fd65d9 100644
--- a/mp4.h
+++ b/mp4.h
@@ -33,9 +33,7 @@ struct mp4 *mp4_open_meta(const struct mp4_callback *cb);
 
 int mp4_meta_get_by_index(const struct mp4 *f, unsigned int index,
                             char **item, char **value);
-int32_t mp4_meta_update(const struct mp4_callback *cb,
-		const struct mp4_metadata *data);
-
+int32_t mp4_meta_update(struct mp4 *f, struct mp4_metadata *meta);
 int mp4_meta_get_num_items(const struct mp4 *f);
 char *mp4_meta_get_artist(const struct mp4 *f);
 char *mp4_meta_get_title(const struct mp4 *f);