From 5cc405db433ea1bc934503ebb457c639190c40a0 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@tuebingen.mpg.de>
Date: Wed, 11 Aug 2021 22:52:11 +0200
Subject: [PATCH] mp4: Rename and simplify set_metadata_name()

This function is an atrocious mess. For one, the naming is confusing
because the function does not set the atom name, it *returns* it.
More importantly, the function defines a static array for no good
reason and then hard-codes the array indices in a large switch
statement.

It's much easier to simply return a pointer to a string literal and
perform the strdup operation in the single caller.
---
 mp4.c | 151 ++++++++++++++--------------------------------------------
 1 file changed, 36 insertions(+), 115 deletions(-)

diff --git a/mp4.c b/mp4.c
index b8746e32..c97fa477 100644
--- a/mp4.c
+++ b/mp4.c
@@ -668,118 +668,41 @@ static char *read_string(struct mp4 *f, uint32_t length)
 	return str;
 }
 
-static int32_t set_metadata_name(uint8_t atom_type, char **name)
-{
-	static char *tag_names[] = {
-		"unknown", "title", "artist", "writer", "album",
-		"date", "tool", "comment", "genre", "track",
-		"disc", "compilation", "genre", "tempo", "cover",
-		"album_artist", "contentgroup", "lyrics", "description",
-		"network", "show", "episodename",
-		"sorttitle", "sortalbum", "sortartist", "sortalbumartist",
-		"sortwriter", "sortshow",
-		"season", "episode", "podcast"
-	};
-	uint8_t tag_idx = 0;
-
+static const char *get_metadata_name(uint8_t atom_type)
+{
 	switch (atom_type) {
-	case ATOM_TITLE:
-		tag_idx = 1;
-		break;
-	case ATOM_ARTIST:
-		tag_idx = 2;
-		break;
-	case ATOM_WRITER:
-		tag_idx = 3;
-		break;
-	case ATOM_ALBUM:
-		tag_idx = 4;
-		break;
-	case ATOM_DATE:
-		tag_idx = 5;
-		break;
-	case ATOM_TOOL:
-		tag_idx = 6;
-		break;
-	case ATOM_COMMENT:
-		tag_idx = 7;
-		break;
-	case ATOM_GENRE1:
-		tag_idx = 8;
-		break;
-	case ATOM_TRACK:
-		tag_idx = 9;
-		break;
-	case ATOM_DISC:
-		tag_idx = 10;
-		break;
-	case ATOM_COMPILATION:
-		tag_idx = 11;
-		break;
-	case ATOM_GENRE2:
-		tag_idx = 12;
-		break;
-	case ATOM_TEMPO:
-		tag_idx = 13;
-		break;
-	case ATOM_COVER:
-		tag_idx = 14;
-		break;
-	case ATOM_ALBUM_ARTIST:
-		tag_idx = 15;
-		break;
-	case ATOM_CONTENTGROUP:
-		tag_idx = 16;
-		break;
-	case ATOM_LYRICS:
-		tag_idx = 17;
-		break;
-	case ATOM_DESCRIPTION:
-		tag_idx = 18;
-		break;
-	case ATOM_NETWORK:
-		tag_idx = 19;
-		break;
-	case ATOM_SHOW:
-		tag_idx = 20;
-		break;
-	case ATOM_EPISODENAME:
-		tag_idx = 21;
-		break;
-	case ATOM_SORTTITLE:
-		tag_idx = 22;
-		break;
-	case ATOM_SORTALBUM:
-		tag_idx = 23;
-		break;
-	case ATOM_SORTARTIST:
-		tag_idx = 24;
-		break;
-	case ATOM_SORTALBUMARTIST:
-		tag_idx = 25;
-		break;
-	case ATOM_SORTWRITER:
-		tag_idx = 26;
-		break;
-	case ATOM_SORTSHOW:
-		tag_idx = 27;
-		break;
-	case ATOM_SEASON:
-		tag_idx = 28;
-		break;
-	case ATOM_EPISODE:
-		tag_idx = 29;
-		break;
-	case ATOM_PODCAST:
-		tag_idx = 30;
-		break;
-	default:
-		tag_idx = 0;
-		break;
+	case ATOM_TITLE: return "title";
+	case ATOM_ARTIST: return "artist";
+	case ATOM_WRITER: return "writer";
+	case ATOM_ALBUM: return "album";
+	case ATOM_DATE: return "date";
+	case ATOM_TOOL: return "tool";
+	case ATOM_COMMENT: return "comment";
+	case ATOM_GENRE1: return "genre";
+	case ATOM_TRACK: return "track";
+	case ATOM_DISC: return "disc";
+	case ATOM_COMPILATION: return "compilation";
+	case ATOM_GENRE2: return "genre";
+	case ATOM_TEMPO: return "tempo";
+	case ATOM_COVER: return "cover";
+	case ATOM_ALBUM_ARTIST: return "album_artist";
+	case ATOM_CONTENTGROUP: return "contentgroup";
+	case ATOM_LYRICS: return "lyrics";
+	case ATOM_DESCRIPTION: return "description";
+	case ATOM_NETWORK: return "network";
+	case ATOM_SHOW: return "show";
+	case ATOM_EPISODENAME: return "episodename";
+	case ATOM_SORTTITLE: return "sorttitle";
+	case ATOM_SORTALBUM: return "sortalbum";
+	case ATOM_SORTARTIST: return "sortartist";
+	case ATOM_SORTALBUMARTIST: return "sortalbumartist";
+	case ATOM_SORTWRITER: return "sortwriter";
+	case ATOM_SORTSHOW: return "sortshow";
+	case ATOM_SEASON: return "season";
+	case ATOM_EPISODE: return "episode";
+	case ATOM_PODCAST: return "podcast";
+	default: return "unknown";
 	}
-
-	*name = para_strdup(tag_names[tag_idx]);
-	return 0;
 }
 
 static uint32_t min_body_size(uint8_t atom_type)
@@ -884,12 +807,10 @@ static int32_t parse_tag(struct mp4 *f, uint8_t parent, int32_t size)
 	}
 	if (data) {
 		if (!done) {
-			if (name == NULL)
-				set_metadata_name(parent , &name);
-			if (name)
-				tag_add_field(&(f->tags), name, data, len);
+			if (!name)
+				name = para_strdup(get_metadata_name(parent));
+			tag_add_field(&(f->tags), name, data, len);
 		}
-
 		free(data);
 	}
 	free(name);
-- 
2.39.2