Merge remote-tracking branch 'remotes/vivier2/tags/trivial-branch-for-5.2-pull-reques...
[qemu.git] / include / hw / stream.h
1 #ifndef STREAM_H
2 #define STREAM_H
3
4 #include "qom/object.h"
5
6 /* stream slave. Used until qdev provides a generic way. */
7 #define TYPE_STREAM_SLAVE "stream-slave"
8
9 #define STREAM_SLAVE_CLASS(klass) \
10 OBJECT_CLASS_CHECK(StreamSlaveClass, (klass), TYPE_STREAM_SLAVE)
11 #define STREAM_SLAVE_GET_CLASS(obj) \
12 OBJECT_GET_CLASS(StreamSlaveClass, (obj), TYPE_STREAM_SLAVE)
13 #define STREAM_SLAVE(obj) \
14 INTERFACE_CHECK(StreamSlave, (obj), TYPE_STREAM_SLAVE)
15
16 typedef struct StreamSlave StreamSlave;
17
18 typedef void (*StreamCanPushNotifyFn)(void *opaque);
19
20 typedef struct StreamSlaveClass {
21 InterfaceClass parent;
22 /**
23 * can push - determine if a stream slave is capable of accepting at least
24 * one byte of data. Returns false if cannot accept. If not implemented, the
25 * slave is assumed to always be capable of receiving.
26 * @notify: Optional callback that the slave will call when the slave is
27 * capable of receiving again. Only called if false is returned.
28 * @notify_opaque: opaque data to pass to notify call.
29 */
30 bool (*can_push)(StreamSlave *obj, StreamCanPushNotifyFn notify,
31 void *notify_opaque);
32 /**
33 * push - push data to a Stream slave. The number of bytes pushed is
34 * returned. If the slave short returns, the master must wait before trying
35 * again, the slave may continue to just return 0 waiting for the vm time to
36 * advance. The can_push() function can be used to trap the point in time
37 * where the slave is ready to receive again, otherwise polling on a QEMU
38 * timer will work.
39 * @obj: Stream slave to push to
40 * @buf: Data to write
41 * @len: Maximum number of bytes to write
42 * @eop: End of packet flag
43 */
44 size_t (*push)(StreamSlave *obj, unsigned char *buf, size_t len, bool eop);
45 } StreamSlaveClass;
46
47 size_t
48 stream_push(StreamSlave *sink, uint8_t *buf, size_t len, bool eop);
49
50 bool
51 stream_can_push(StreamSlave *sink, StreamCanPushNotifyFn notify,
52 void *notify_opaque);
53
54
55 #endif /* STREAM_H */