mp4: Simplify and doxify meta tag accessors.

[paraslash.git] / mp4.c

diff --git a/mp4.c b/mp4.c
index deb05747072f9500af5bfab2e98eeffbbe50e2e1..f576529c0a954967e327834ae2b4e0bd204f24e2 100644 (file)
--- 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)
@@ -1760,47 +1747,70 @@ int32_t mp4_meta_update(const struct mp4_callback *cb,
        return 1;
 }
 
-/* find a metadata item by name */
-/* returns 0 if item found, 1 if no such item */
-static int32_t meta_find_by_name(const struct mp4 *f, const char *item,
-               char **value)
+static char *meta_find_by_name(const struct mp4 *f, const char *item)
 {
        uint32_t i;
 
-       for (i = 0; i < f->tags.count; i++) {
-               if (!strcasecmp(f->tags.tags[i].item, item)) {
-                       *value = para_strdup(f->tags.tags[i].value);
-                       return 1;
-               }
-       }
-
-       *value = NULL;
-
-       /* not found */
-       return 0;
+       for (i = 0; i < f->tags.count; i++)
+               if (!strcasecmp(f->tags.tags[i].item, item))
+                       return para_strdup(f->tags.tags[i].value);
+       return NULL;
 }
 
-int32_t mp4_meta_get_artist(const struct mp4 *f, char **value)
+/**
+ * Return the value of the artist meta tag of an mp4 file.
+ *
+ * \param f Must not be NULL.
+ *
+ * \return If the file does not contain this metadata tag, the function returns
+ * NULL. Otherwise, a copy of the tag value is returned. The caller should free
+ * this memory when it is no longer needed.
+ */
+char *mp4_meta_get_artist(const struct mp4 *f)
 {
-       return meta_find_by_name(f, "artist", value);
+       return meta_find_by_name(f, "artist");
 }
 
-int32_t mp4_meta_get_title(const struct mp4 *f, char **value)
+/**
+ * Return the value of the title meta tag of an mp4 file.
+ *
+ * \param f See \ref mp4_meta_get_artist().
+ * \return See \ref mp4_meta_get_artist().
+ */
+char *mp4_meta_get_title(const struct mp4 *f)
 {
-       return meta_find_by_name(f, "title", value);
+       return meta_find_by_name(f, "title");
 }
 
-int32_t mp4_meta_get_date(const struct mp4 *f, char **value)
+/**
+ * Return the value of the date meta tag of an mp4 file.
+ *
+ * \param f See \ref mp4_meta_get_artist().
+ * \return See \ref mp4_meta_get_artist().
+ */
+char *mp4_meta_get_date(const struct mp4 *f)
 {
-       return meta_find_by_name(f, "date", value);
+       return meta_find_by_name(f, "date");
 }
 
-int32_t mp4_meta_get_album(const struct mp4 *f, char **value)
+/**
+ * Return the value of the album meta tag of an mp4 file.
+ *
+ * \param f See \ref mp4_meta_get_artist().
+ * \return See \ref mp4_meta_get_artist().
+ */
+char *mp4_meta_get_album(const struct mp4 *f)
 {
-       return meta_find_by_name(f, "album", value);
+       return meta_find_by_name(f, "album");
 }
 
-int32_t mp4_meta_get_comment(const struct mp4 *f, char **value)
+/**
+ * Return the value of the comment meta tag of an mp4 file.
+ *
+ * \param f See \ref mp4_meta_get_artist().
+ * \return See \ref mp4_meta_get_artist().
+ */
+char *mp4_meta_get_comment(const struct mp4 *f)
 {
-       return meta_find_by_name(f, "comment", value);
+       return meta_find_by_name(f, "comment");
 }