implemented the 'consume' mode

Consume mode removes each song played

doc/protocol.xml

@@ -222,6 +222,12 @@
                 <returnvalue>0 or 1</returnvalue>
                </para>
               </listitem>
+              <listitem>
+               <para>
+                <varname>consume</varname>:
+                <returnvalue>0 or 1</returnvalue>
+               </para>
+              </listitem>
               <listitem>
                 <para>
                   <varname>playlist</varname>:
@@ -352,6 +358,21 @@
     <section>
       <title>Playback options</title>
 
+        <varlistentry id="command_consume">
+          <term>
+            <cmdsynopsis>
+              <command>consume</command>
+              <arg choice="req"><replaceable>STATE</replaceable></arg>
+            </cmdsynopsis>
+          </term>
+          <listitem>
+            <para>
+              Sets consume state to <varname>STATE</varname>,
+              <varname>STATE</varname> should be 0 or 1.
+	      When consume is activated, each song played is removed from playlist.
+            </para>
+          </listitem>
+        </varlistentry>
       <variablelist>
         <varlistentry id="command_crossfade">
           <term>

src/command.c

@@ -60,6 +60,7 @@
 #define COMMAND_STATUS_STATE            "state"
 #define COMMAND_STATUS_REPEAT           "repeat"
 #define COMMAND_STATUS_SINGLE           "single"
+#define COMMAND_STATUS_CONSUME          "consume"
 #define COMMAND_STATUS_RANDOM           "random"
 #define COMMAND_STATUS_PLAYLIST         "playlist"
 #define COMMAND_STATUS_PLAYLIST_LENGTH  "playlistlength"
@@ -471,6 +472,7 @@ handle_status(struct client *client,
 		      COMMAND_STATUS_REPEAT ": %i\n"
 		      COMMAND_STATUS_RANDOM ": %i\n"
 		      COMMAND_STATUS_SINGLE ": %i\n"
+		      COMMAND_STATUS_CONSUME ": %i\n"
 		      COMMAND_STATUS_PLAYLIST ": %li\n"
 		      COMMAND_STATUS_PLAYLIST_LENGTH ": %i\n"
 		      COMMAND_STATUS_CROSSFADE ": %i\n"
@@ -479,6 +481,7 @@ handle_status(struct client *client,
 		      getPlaylistRepeatStatus(&g_playlist),
 		      getPlaylistRandomStatus(&g_playlist),
 		      getPlaylistSingleStatus(&g_playlist),
+		      getPlaylistConsumeStatus(&g_playlist),
 		      getPlaylistVersion(&g_playlist),
 		      getPlaylistLength(&g_playlist),
 		      (int)(getPlayerCrossFade() + 0.5),
@@ -1113,6 +1116,24 @@ handle_single(struct client *client, G_GNUC_UNUSED int argc, char *argv[])
 	return COMMAND_RETURN_OK;
 }
 
+static enum command_return
+handle_consume(struct client *client, G_GNUC_UNUSED int argc, char *argv[])
+{
+	int status;
+
+	if (!check_int(client, &status, argv[1], need_integer))
+		return COMMAND_RETURN_ERROR;
+
+	if (status != 0 && status != 1) {
+		command_error(client, ACK_ERROR_ARG,
+			      "\"%i\" is not 0 or 1", status);
+		return COMMAND_RETURN_ERROR;
+	}
+
+	setPlaylistConsumeStatus(&g_playlist, status);
+	return COMMAND_RETURN_OK;
+}
+
 static enum command_return
 handle_random(struct client *client, G_GNUC_UNUSED int argc, char *argv[])
 {
@@ -1573,6 +1594,7 @@ static const struct command commands[] = {
 	{ "clearerror", PERMISSION_CONTROL, 0, 0, handle_clearerror },
 	{ "close", PERMISSION_NONE, -1, -1, handle_close },
 	{ "commands", PERMISSION_NONE, 0, 0, handle_commands },
+	{ "consume", PERMISSION_CONTROL, 1, 1, handle_consume },
 	{ "count", PERMISSION_READ, 2, -1, handle_count },
 	{ "crossfade", PERMISSION_CONTROL, 1, 1, handle_crossfade },
 	{ "currentsong", PERMISSION_READ, 0, 0, handle_currentsong },

src/playlist.c

@@ -100,9 +100,13 @@ static void syncPlaylistWithQueue(struct playlist *playlist)
 		/* queued song has started: copy queued to current,
 		   and notify the clients */
 
+		int current = playlist->current;
 		playlist->current = playlist->queued;
 		playlist->queued = -1;
 
+		if(playlist->queue.consume)
+			deleteFromPlaylist(playlist, queue_order_to_position(&playlist->queue, current));
+
 		idle_add(IDLE_PLAYER);
 	}
 }
@@ -267,6 +271,12 @@ getPlaylistSingleStatus(const struct playlist *playlist)
 	return playlist->queue.single;
 }
 
+bool
+getPlaylistConsumeStatus(const struct playlist *playlist)
+{
+	return playlist->queue.consume;
+}
+
 void setPlaylistRepeatStatus(struct playlist *playlist, bool status)
 {
 	if (status == playlist->queue.repeat)
@@ -307,6 +317,15 @@ void setPlaylistSingleStatus(struct playlist *playlist, bool status)
 	idle_add(IDLE_OPTIONS);
 }
 
+void setPlaylistConsumeStatus(struct playlist *playlist, bool status)
+{
+	if (status == playlist->queue.consume)
+		return;
+
+	playlist->queue.consume = status;
+	idle_add(IDLE_OPTIONS);
+}
+
 void setPlaylistRandomStatus(struct playlist *playlist, bool status)
 {
 	const struct song *queued;

src/playlist.h

@@ -184,6 +184,11 @@ getPlaylistSingleStatus(const struct playlist *playlist);
 
 void setPlaylistSingleStatus(struct playlist *playlist, bool status);
 
+bool
+getPlaylistConsumeStatus(const struct playlist *playlist);
+
+void setPlaylistConsumeStatus(struct playlist *playlist, bool status);
+
 int getPlaylistCurrentSong(const struct playlist *playlist);
 
 int getPlaylistNextSong(const struct playlist *playlist);

src/playlist_control.c

@@ -139,6 +139,7 @@ void
 nextSongInPlaylist(struct playlist *playlist)
 {
 	int next_order;
+	int current;
 
 	if (!playlist->playing)
 		return;
@@ -146,6 +147,7 @@ nextSongInPlaylist(struct playlist *playlist)
 	assert(!queue_is_empty(&playlist->queue));
 	assert(queue_valid_order(&playlist->queue, playlist->current));
 
+	current = playlist->current;
 	playlist->stop_on_error = false;
 
 	/* determine the next song from the queue's order list */
@@ -156,9 +158,9 @@ nextSongInPlaylist(struct playlist *playlist)
 		playlist->queue.single = false;
 		/* no song after this one: stop playback */
 		stopPlaylist(playlist);
-		return;
 	}
-
+	else
+	{
 		if (next_order == 0 && playlist->queue.random) {
 			/* The queue told us that the next song is the first
 			   song.  This means we are in repeat mode.  Shuffle
@@ -176,6 +178,11 @@ nextSongInPlaylist(struct playlist *playlist)
 		playPlaylistOrderNumber(playlist, next_order);
 	}
 
+	/* Consume mode removes each played songs. */
+	if(playlist->queue.consume)
+		deleteFromPlaylist(playlist, queue_order_to_position(&playlist->queue, current));
+}
+
 void previousSongInPlaylist(struct playlist *playlist)
 {
 	static time_t lastTime;

src/playlist_state.c

@@ -35,6 +35,7 @@
 #define PLAYLIST_STATE_FILE_RANDOM		"random: "
 #define PLAYLIST_STATE_FILE_REPEAT		"repeat: "
 #define PLAYLIST_STATE_FILE_SINGLE		"single: "
+#define PLAYLIST_STATE_FILE_CONSUME		"consume: "
 #define PLAYLIST_STATE_FILE_CURRENT		"current: "
 #define PLAYLIST_STATE_FILE_TIME		"time: "
 #define PLAYLIST_STATE_FILE_CROSSFADE		"crossfade: "
@@ -74,6 +75,8 @@ playlist_state_save(FILE *fp, const struct playlist *playlist)
 		playlist->queue.repeat);
 	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_SINGLE,
 		playlist->queue.single);
+	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CONSUME,
+		playlist->queue.consume);
 	fprintf(fp, "%s%i\n", PLAYLIST_STATE_FILE_CROSSFADE,
 		(int)(getPlayerCrossFade()));
 	fprintf(fp, "%s\n", PLAYLIST_STATE_FILE_PLAYLIST_BEGIN);
@@ -146,6 +149,13 @@ playlist_state_restore(FILE *fp, struct playlist *playlist)
 				setPlaylistSingleStatus(playlist, true);
 			} else
 				setPlaylistSingleStatus(playlist, false);
+		} else if (g_str_has_prefix(buffer, PLAYLIST_STATE_FILE_CONSUME)) {
+			if (strcmp
+			    (&(buffer[strlen(PLAYLIST_STATE_FILE_CONSUME)]),
+			     "1") == 0) {
+				setPlaylistConsumeStatus(playlist, true);
+			} else
+				setPlaylistConsumeStatus(playlist, false);
 		} else if (g_str_has_prefix(buffer, PLAYLIST_STATE_FILE_CROSSFADE)) {
 			setPlayerCrossFade(atoi
 					   (&

src/queue.c

@@ -283,6 +283,7 @@ queue_init(struct queue *queue, unsigned max_length)
 	queue->repeat = false;
 	queue->random = false;
 	queue->single = false;
+	queue->consume = false;
 
 	queue->items = g_new(struct queue_item, max_length);
 	queue->order = g_malloc(sizeof(queue->order[0]) *

src/queue.h

@@ -84,6 +84,9 @@ struct queue {
 	/** play only current song. */
 	bool single;
 
+	/** remove each played files. */
+	bool consume;
+
 	/** play back songs in random order? */
 	bool random;