core/queue: Add qop_init() queue operation

This function is used to notify a higher layer that a queue has been
initialized.  That higher layer can return a pointer to be attached to
the "private data" field of the queue.

Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>

core/queue.c

@@ -29,6 +29,13 @@ static int track_less_than(const void *a, const void *b, void *data)
 	return res;
 }
 
+static inline void *__queue_init(struct queue *queue)
+{
+	if (queue->q_ops)
+		return queue->q_ops->qop_init(queue);
+	return NULL;
+}
+
 static inline unsigned int __queue_added(struct queue *queue,
 					 struct track *track,
 					 unsigned int pos)
@@ -89,8 +96,9 @@ void queue_init(struct queue *queue, unsigned int flags,
 
 	queue->q_cur.it_pos  = -1;
 	queue->q_cur.it_iter = NULL;
-
 	_q_init(&queue->q_tracks);
+
+	queue->q_private = __queue_init(queue);
 }
 
 void queue_deinit(struct queue *queue)

gui/collection_tab.cpp

@@ -53,6 +53,11 @@ public:
 
 static CollectionTab *collection_tab;
 
+static void *collection_init(struct queue *queue)
+{
+	return collection_tab;
+}
+
 static void collection_added(struct queue *queue, unsigned int pos)
 {
 	if (collection_tab)
@@ -78,6 +83,7 @@ static void collection_updated(struct queue *queue, unsigned int pos)
 }
 
 struct queue_ops collection_ops = {
+	collection_init,
 	collection_added,
 	collection_removed,
 	collection_cleared,

gui/history.cpp

@@ -38,6 +38,11 @@ public:
 
 static HistoryTab *history_tab;
 
+static void *history_init(struct queue *queue)
+{
+	return history_tab;
+}
+
 static void history_added(struct queue *queue, unsigned int pos)
 {
 	if (history_tab)
@@ -60,6 +65,7 @@ static void history_updated(struct queue *queue, unsigned int pos)
 }
 
 struct queue_ops history_ops = {
+	history_init,
 	history_added,
 	history_removed,
 	history_cleared,

gui/playlist_tab.cpp

@@ -84,6 +84,11 @@ static void on_favorite()
 		playlist_remove(PL_FAVORITED, track);
 }
 
+static void *playlist_init(struct queue *queue)
+{
+	return p_tab;
+}
+
 static void playlist_added(struct queue *queue, unsigned int pos)
 {
 	if (p_tab)
@@ -106,6 +111,7 @@ static void playlist_updated(struct queue *queue, unsigned int pos)
 }
 
 struct queue_ops playlist_ops = {
+	playlist_init,
 	playlist_added,
 	playlist_removed,
 	playlist_cleared,

gui/tabs.cpp

@@ -23,6 +23,11 @@ static compare_t sort_fields[] = {
 		COMPARE_GENRE,  COMPARE_COUNT, COMPARE_PLAYED
 };
 
+static void *tempq_init(struct queue *queue)
+{
+	return NULL;
+}
+
 static void tempq_added(struct queue *queue, unsigned int pos)
 {
 	find_tab(queue)->on_track_added(pos);
@@ -46,6 +51,7 @@ static void tempq_updated(struct queue *queue, unsigned int pos)
 }
 
 struct queue_ops tempq_ops = {
+	tempq_init,
 	tempq_added,
 	tempq_removed,
 	tempq_cleared,

include/core/queue.h

@@ -27,6 +27,9 @@ enum queue_flags {
 
 
 struct queue_ops {
+	/* Called to tell a higher layer that a queue has been initialized. */
+	void *(*qop_init)(struct queue *);
+
 	/* Called to tell a higher layer that a track has been added. */
 	void (*qop_added)(struct queue *, unsigned int);
 
@@ -45,11 +48,12 @@ struct queue_ops {
 
 
 struct queue {
-	unsigned int   q_flags;  /* The queue's set of flags.               */
-	unsigned int   q_length; /* The queue's total runtime (in seconds). */
-	struct _queue  q_tracks; /* The queue's list of tracks.             */
-	struct _q_iter q_cur;    /* The queue's last-played position.       */
-	GSList        *q_sort;   /* The queue's sort order.                 */
+	unsigned int   q_flags;   /* The queue's set of flags.               */
+	unsigned int   q_length;  /* The queue's total runtime (in seconds). */
+	struct _queue  q_tracks;  /* The queue's list of tracks.             */
+	struct _q_iter q_cur;     /* The queue's last-played position.       */
+	GSList        *q_sort;    /* The queue's sort order.                 */
+	void          *q_private; /*  The queue's private data.              */
 
 	const struct queue_ops *q_ops; /* The queue's operations vector. */
 };

tests/core/queue.c

@@ -8,6 +8,7 @@
 #include <tests/test.h>
 
 
+unsigned int count_init    = 0;
 unsigned int count_added   = 0;
 unsigned int count_deleted = 0;
 unsigned int count_cleared = 0;
@@ -16,6 +17,12 @@ unsigned int count_sort    = 0;
 unsigned int count_updated = 0;
 
 
+static void *queue_op_init(struct queue *queue)
+{
+	count_init++;
+	return GUINT_TO_POINTER(count_init);
+}
+
 static void queue_op_added(struct queue *queue, unsigned int pos)
 {
 	count_added++;
@@ -46,6 +53,7 @@ static void queue_op_updated(struct queue *queue, unsigned int pos)
 
 
 static const struct queue_ops test_ops = {
+	.qop_init    = queue_op_init,
 	.qop_added   = queue_op_added,
 	.qop_removed = queue_op_removed,
 	.qop_cleared = queue_op_cleared,
@@ -91,6 +99,9 @@ static void test_init()
 	__test_init_core();
 
 	queue_init(&q, 0, NULL);
+	test_equal(count_init, 0);
+	test_equal(GPOINTER_TO_UINT(q.q_private), 0);
+
 	test_equal(q.q_cur.it_pos, (unsigned int)-1);
 	test_equal(q.q_flags,  0);
 	test_equal(q.q_length, 0);
@@ -99,6 +110,8 @@ static void test_init()
 	test_equal((void *)queue_next(&q), (void *)NULL);
 
 	queue_init(&q, Q_ENABLED | Q_RANDOM, &test_ops);
+	test_equal(count_init, 1);
+	test_equal(GPOINTER_TO_UINT(q.q_private), 1);
 
 	test_equal(q.q_cur.it_pos, (unsigned int)-1);
 	test_equal(q.q_flags,  Q_ENABLED | Q_RANDOM);