1 /* GStreamer
2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
4 *
5 * gstqueue.h:
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
21 */
24 #ifndef __GST_QUEUE_H__
25 #define __GST_QUEUE_H__
27 #include <gst/gst.h>
29 G_BEGIN_DECLS
31 #define GST_TYPE_QUEUE \
32 (gst_queue_get_type())
33 #define GST_QUEUE(obj) \
34 (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_QUEUE,GstQueue))
35 #define GST_QUEUE_CLASS(klass) \
36 (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_QUEUE,GstQueueClass))
37 #define GST_IS_QUEUE(obj) \
38 (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_QUEUE))
39 #define GST_IS_QUEUE_CLASS(klass) \
40 (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_QUEUE))
42 typedef struct _GstQueue GstQueue;
43 typedef struct _GstQueueSize GstQueueSize;
44 typedef enum _GstQueueLeaky GstQueueLeaky;
45 typedef struct _GstQueueClass GstQueueClass;
47 /**
48 * GstQueueLeaky:
49 * @GST_QUEUE_NO_LEAK: Not Leaky
50 * @GST_QUEUE_LEAK_UPSTREAM: Leaky on upstream (new buffers)
51 * @GST_QUEUE_LEAK_DOWNSTREAM: Leaky on downstream (old buffers)
52 *
53 * Buffer dropping scheme to avoid the queue to block when full.
54 */
55 enum _GstQueueLeaky {
56 GST_QUEUE_NO_LEAK = 0,
57 GST_QUEUE_LEAK_UPSTREAM = 1,
58 GST_QUEUE_LEAK_DOWNSTREAM = 2
59 };
61 /*
62 * GstQueueSize:
63 * @buffers: number of buffers
64 * @bytes: number of bytes
65 * @time: amount of time
66 *
67 * Structure describing the size of a queue.
68 */
69 struct _GstQueueSize {
70 guint buffers;
71 guint bytes;
72 guint64 time;
73 };
75 #define GST_QUEUE_CLEAR_LEVEL(l) G_STMT_START { \
76 l.buffers = 0; \
77 l.bytes = 0; \
78 l.time = 0; \
79 } G_STMT_END
81 /**
82 * GstQueue:
83 *
84 * Opaque #GstQueue structure.
85 */
86 struct _GstQueue {
87 GstElement element;
89 /*< private >*/
90 GstPad *sinkpad;
91 GstPad *srcpad;
93 /* segments to keep track of timestamps */
94 GstSegment sink_segment;
95 GstSegment src_segment;
97 /* position of src/sink */
98 GstClockTime sinktime, srctime;
99 /* TRUE if either position needs to be recalculated */
100 gboolean sink_tainted, src_tainted;
102 /* flowreturn when srcpad is paused */
103 GstFlowReturn srcresult;
104 gboolean unexpected;
105 gboolean eos;
107 /* the queue of data we're keeping our grubby hands on */
108 GQueue queue;
110 GstQueueSize
111 cur_level, /* currently in the queue */
112 max_size, /* max. amount of data allowed in the queue */
113 min_threshold, /* min. amount of data required to wake reader */
114 orig_min_threshold; /* Original min.threshold, for reset in EOS */
116 /* whether we leak data, and at which end */
117 gint leaky;
119 GMutex *qlock; /* lock for queue (vs object lock) */
120 gboolean waiting_add;
121 GCond *item_add; /* signals buffers now available for reading */
122 gboolean waiting_del;
123 GCond *item_del; /* signals space now available for writing */
125 gboolean head_needs_discont, tail_needs_discont;
126 gboolean push_newsegment;
128 gboolean silent; /* don't emit signals */
130 /* whether the first new segment has been applied to src */
131 gboolean newseg_applied_to_src;
132 };
134 struct _GstQueueClass {
135 GstElementClass parent_class;
137 /* signals - 'running' is called from both sides
138 * which might make it sort of non-useful... */
139 void (*underrun) (GstQueue *queue);
140 void (*running) (GstQueue *queue);
141 void (*overrun) (GstQueue *queue);
143 void (*pushing) (GstQueue *queue);
144 };
146 GType gst_queue_get_type (void);
148 G_END_DECLS
151 #endif /* __GST_QUEUE_H__ */