From: Andre Noll <maan@tuebingen.mpg.de>
Date: Fri, 13 Aug 2021 18:19:43 +0000 (+0200)
Subject: mp4: Simplify parse_tag().
X-Git-Tag: v0.7.1~7^2~87
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=06dd900e86fee406c52f18b7dcf81f7487cb7cb6;p=paraslash.git

mp4: Simplify parse_tag().

We don't care about arbitrarily named tags, and those tags we're
interested in are generally present in form of the standard tags
(ATOM_TITLE, ATOM_ARTIST etc.).

Since we now always call get_metadata_name() to get the string
representation of the tag, we don't need to make a copy any more,
just pass the const pointer directly to tag_add_field().

With this change in place it is obvious that we never pass a NULL or
empty tag name to tag_add_field(), and we don't pass a NULL pointer
for the value argument either, so remove the safety check.
---

diff --git a/mp4.c b/mp4.c
index deb05747..d8aea783 100644
--- a/mp4.c
+++ b/mp4.c
@@ -599,8 +599,6 @@ static int32_t read_stsd(struct mp4 *f)
 static int32_t tag_add_field(struct mp4_metadata *tags, const char *item,
 		const char *value, int32_t len)
 {
-	if (!item || (item && !*item) || !value)
-		return 0;
 	tags->tags = para_realloc(tags->tags,
 		(tags->count + 1) * sizeof(struct mp4_tag));
 	tags->tags[tags->count].item = para_strdup(item);
@@ -673,7 +671,6 @@ static const char *get_metadata_name(uint8_t atom_type)
 static void parse_tag(struct mp4 *f, uint8_t parent, int32_t size)
 {
 	uint64_t subsize, sumsize;
-	char *name = NULL;
 	char *data = NULL;
 	uint32_t len = 0;
 	uint64_t destpos;
@@ -687,13 +684,6 @@ static void parse_tag(struct mp4 *f, uint8_t parent, int32_t size)
 		uint8_t header_size = 0;
 		subsize = atom_read_header(f, &atom_type, &header_size);
 		destpos = get_position(f) + subsize - header_size;
-		if (atom_type == ATOM_NAME) {
-			read_char(f);	/* version */
-			read_int24(f);	/* flags */
-			free(name);
-			name = read_string(f, subsize - (header_size + 4));
-			continue;
-		}
 		if (atom_type != ATOM_DATA)
 			continue;
 		read_char(f);	/* version */
@@ -703,13 +693,10 @@ static void parse_tag(struct mp4 *f, uint8_t parent, int32_t size)
 		data = read_string(f, subsize - (header_size + 8));
 		len = subsize - (header_size + 8);
 	}
-	if (data) {
-		if (!name)
-			name = para_strdup(get_metadata_name(parent));
-		tag_add_field(&(f->tags), name, data, len);
-		free(data);
-	}
-	free(name);
+	if (!data)
+		return;
+	tag_add_field(&f->tags, get_metadata_name(parent), data, len);
+	free(data);
 }
 
 static int32_t read_mdhd(struct mp4 *f)