From b8443efbe313b7b32e7e58555139fd6c03a40957 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@duempel.org>
Date: Tue, 29 Sep 2009 22:14:20 +0200
Subject: [PATCH] playlist: make functions const

And return const mpd_song objects.
---
 src/main.c          |  2 +-
 src/mpdclient.c     |  2 +-
 src/mpdclient.h     |  2 +-
 src/playlist.c      |  8 ++++----
 src/playlist.h      |  8 ++++----
 src/screen_lyrics.c | 22 +++++++++-------------
 6 files changed, 20 insertions(+), 24 deletions(-)

diff --git a/src/main.c b/src/main.c
index 10706a5..fb5de59 100644
--- a/src/main.c
+++ b/src/main.c
@@ -85,7 +85,7 @@ update_xterm_title(void)
 	static char title[BUFSIZE];
 	char tmp[BUFSIZE];
 	struct mpd_status *status = NULL;
-	struct mpd_song *song = NULL;
+	const struct mpd_song *song = NULL;
 
 	if (mpd) {
 		status = mpd->status;
diff --git a/src/mpdclient.c b/src/mpdclient.c
index ac7fce9..cbc6a91 100644
--- a/src/mpdclient.c
+++ b/src/mpdclient.c
@@ -269,7 +269,7 @@ mpdclient_update(struct mpdclient *c)
 gint
 mpdclient_cmd_play(struct mpdclient *c, gint idx)
 {
-	struct mpd_song *song = playlist_get_song(&c->playlist, idx);
+	const struct mpd_song *song = playlist_get_song(&c->playlist, idx);
 
 	if (MPD_ERROR(c))
 		return -1;
diff --git a/src/mpdclient.h b/src/mpdclient.h
index 52fcdb4..e2b81c8 100644
--- a/src/mpdclient.h
+++ b/src/mpdclient.h
@@ -18,7 +18,7 @@ struct mpdclient {
 
 	struct mpd_connection *connection;
 	struct mpd_status *status;
-	struct mpd_song *song;
+	const struct mpd_song *song;
 
 	int volume;
 	unsigned updatingdb;
diff --git a/src/playlist.c b/src/playlist.c
index 562fde6..5fced75 100644
--- a/src/playlist.c
+++ b/src/playlist.c
@@ -60,8 +60,8 @@ mpdclient_playlist_free(struct mpdclient_playlist *playlist)
 	return 0;
 }
 
-struct mpd_song *
-playlist_get_song(struct mpdclient_playlist *playlist, gint idx)
+const struct mpd_song *
+playlist_get_song(const struct mpdclient_playlist *playlist, gint idx)
 {
 	if (idx < 0 || (guint)idx >= playlist_length(playlist))
 		return NULL;
@@ -69,8 +69,8 @@ playlist_get_song(struct mpdclient_playlist *playlist, gint idx)
 	return playlist_get(playlist, idx);
 }
 
-struct mpd_song *
-playlist_lookup_song(struct mpdclient_playlist *playlist, unsigned id)
+const struct mpd_song *
+playlist_lookup_song(const struct mpdclient_playlist *playlist, unsigned id)
 {
 	for (guint i = 0; i < playlist_length(playlist); ++i) {
 		struct mpd_song *song = playlist_get(playlist, i);
diff --git a/src/playlist.h b/src/playlist.h
index 580b1c9..cee9100 100644
--- a/src/playlist.h
+++ b/src/playlist.h
@@ -119,11 +119,11 @@ playlist_swap(struct mpdclient_playlist *playlist, guint idx1, guint idx2)
 	g_ptr_array_index(playlist->list, idx2) = song1;
 }
 
-struct mpd_song *
-playlist_lookup_song(struct mpdclient_playlist *playlist, unsigned id);
+const struct mpd_song *
+playlist_lookup_song(const struct mpdclient_playlist *playlist, unsigned id);
 
-struct mpd_song *
-playlist_get_song(struct mpdclient_playlist *playlist, gint index);
+const struct mpd_song *
+playlist_get_song(const struct mpdclient_playlist *playlist, gint index);
 
 gint
 playlist_get_index(const struct mpdclient_playlist *playlist,
diff --git a/src/screen_lyrics.c b/src/screen_lyrics.c
index f9fdb81..abf1055 100644
--- a/src/screen_lyrics.c
+++ b/src/screen_lyrics.c
@@ -202,16 +202,16 @@ lyrics_exit(void)
 static void
 lyrics_open(struct mpdclient *c)
 {
-	if (next_song == NULL)
-		next_song = c->song;
+	const struct mpd_song *next_song_c =
+		next_song != NULL ? next_song : c->song;
 
-	if (next_song != NULL &&
+	if (next_song_c != NULL &&
 	    (current.song == NULL ||
-	     strcmp(mpd_song_get_uri(next_song),
+	     strcmp(mpd_song_get_uri(next_song_c),
 		    mpd_song_get_uri(current.song)) != 0))
-		screen_lyrics_load(next_song);
+		screen_lyrics_load(next_song_c);
 
-	if (next_song != c->song)
+	if (next_song != NULL)
 		mpd_song_free(next_song);
 	next_song = NULL;
 }
@@ -222,15 +222,11 @@ lyrics_update(struct mpdclient *c)
 	if (!follow)
 		return;
 
-	next_song = c->song;
-
-	if (next_song != NULL &&
+	if (c->song != NULL &&
 	    (current.song == NULL ||
-	     strcmp(mpd_song_get_uri(next_song),
+	     strcmp(mpd_song_get_uri(c->song),
 		    mpd_song_get_uri(current.song)) != 0))
-		screen_lyrics_load(next_song);
-
-	next_song = NULL;
+		screen_lyrics_load(c->song);
 }
 
 static const char *
-- 
2.30.2