mpdclient: added mpdclient_cmd_delete_range()

MPD 0.16 supports "delete" with a range argument.

diff --git a/src/mpdclient.c b/src/mpdclient.c
index 33f50184a90e52062d5482abbbd5ab75ff795cca..d60436946a378753538c1711cb653d0ce4bc9c16 100644 (file)
--- a/src/mpdclient.c
+++ b/src/mpdclient.c
@@ -511,6 +511,84 @@ mpdclient_cmd_delete(struct mpdclient *c, gint idx)
        return 0;
 }
 
+/**
+ * Fallback for mpdclient_cmd_delete_range() on MPD older than 0.16.
+ * It emulates the "delete range" command with a list of simple
+ * "delete" commands.
+ */
+static gint
+mpdclient_cmd_delete_range_fallback(struct mpdclient *c,
+                                   unsigned start, unsigned end)
+{
+       if (!mpd_command_list_begin(c->connection, false))
+               return mpdclient_handle_error(c);
+
+       for (; start < end; --end)
+               mpd_send_delete(c->connection, start);
+
+       if (!mpd_command_list_end(c->connection) ||
+           !mpd_response_finish(c->connection))
+               return mpdclient_handle_error(c);
+
+       return 0;
+}
+
+gint
+mpdclient_cmd_delete_range(struct mpdclient *c, unsigned start, unsigned end)
+{
+       struct mpd_status *status;
+
+       if (MPD_ERROR(c))
+               return -1;
+
+       if (mpd_connection_cmp_server_version(c->connection, 0, 16, 0) < 0)
+               return mpdclient_cmd_delete_range_fallback(c, start, end);
+
+       /* MPD 0.16 supports "delete" with a range argument */
+
+       /* send the delete command to mpd; at the same time, get the
+          new status (to verify the playlist id) */
+
+       if (!mpd_command_list_begin(c->connection, false) ||
+           !mpd_send_delete_range(c->connection, start, end) ||
+           !mpd_send_status(c->connection) ||
+           !mpd_command_list_end(c->connection))
+               return mpdclient_handle_error(c);
+
+       c->events |= MPD_IDLE_PLAYLIST;
+
+       status = mpd_recv_status(c->connection);
+       if (status != NULL) {
+               if (c->status != NULL)
+                       mpd_status_free(c->status);
+               c->status = status;
+       }
+
+       if (!mpd_response_finish(c->connection))
+               return mpdclient_handle_error(c);
+
+       if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) - (end - start) &&
+           mpd_status_get_queue_version(status) == c->playlist.version + 1) {
+               /* the cheap route: match on the new playlist length
+                  and its version, we can keep our local playlist
+                  copy in sync */
+               c->playlist.version = mpd_status_get_queue_version(status);
+
+               /* remove the song from the local playlist */
+               while (end > start) {
+                       --end;
+
+                       /* remove references to the song */
+                       if (c->song == playlist_get(&c->playlist, end))
+                               c->song = NULL;
+
+                       playlist_remove(&c->playlist, end);
+               }
+       }
+
+       return 0;
+}
+
 gint
 mpdclient_cmd_move(struct mpdclient *c, gint old_index, gint new_index)
 {

diff --git a/src/mpdclient.h b/src/mpdclient.h
index f363aa9d2a05c297dfcfe5b262453b27eed7dd6d..b06c7a042679d97dde9e6e059057cfb8bb5b4c7f 100644 (file)
--- a/src/mpdclient.h
+++ b/src/mpdclient.h
@@ -80,6 +80,10 @@ gint mpdclient_cmd_add_path(struct mpdclient *c, const gchar *path);
 
 gint mpdclient_cmd_add(struct mpdclient *c, const struct mpd_song *song);
 gint mpdclient_cmd_delete(struct mpdclient *c, gint index);
+
+gint
+mpdclient_cmd_delete_range(struct mpdclient *c, unsigned start, unsigned end);
+
 gint mpdclient_cmd_move(struct mpdclient *c, gint old_index, gint new_index);
 
 gint mpdclient_cmd_save_playlist(struct mpdclient *c, const gchar *filename);