qemu/include/hw/stream.h

58 lines
2.0 KiB
C

#ifndef STREAM_H
#define STREAM_H
#include "qemu-common.h"
#include "qom/object.h"
/* stream slave. Used until qdev provides a generic way. */
#define TYPE_STREAM_SLAVE "stream-slave"
#define STREAM_SLAVE_CLASS(klass) \
OBJECT_CLASS_CHECK(StreamSlaveClass, (klass), TYPE_STREAM_SLAVE)
#define STREAM_SLAVE_GET_CLASS(obj) \
OBJECT_GET_CLASS(StreamSlaveClass, (obj), TYPE_STREAM_SLAVE)
#define STREAM_SLAVE(obj) \
INTERFACE_CHECK(StreamSlave, (obj), TYPE_STREAM_SLAVE)
typedef struct StreamSlave {
Object Parent;
} StreamSlave;
typedef void (*StreamCanPushNotifyFn)(void *opaque);
typedef struct StreamSlaveClass {
InterfaceClass parent;
/**
* can push - determine if a stream slave is capable of accepting at least
* one byte of data. Returns false if cannot accept. If not implemented, the
* slave is assumed to always be capable of receiving.
* @notify: Optional callback that the slave will call when the slave is
* capable of receiving again. Only called if false is returned.
* @notify_opaque: opaque data to pass to notify call.
*/
bool (*can_push)(StreamSlave *obj, StreamCanPushNotifyFn notify,
void *notify_opaque);
/**
* push - push data to a Stream slave. The number of bytes pushed is
* returned. If the slave short returns, the master must wait before trying
* again, the slave may continue to just return 0 waiting for the vm time to
* advance. The can_push() function can be used to trap the point in time
* where the slave is ready to receive again, otherwise polling on a QEMU
* timer will work.
* @obj: Stream slave to push to
* @buf: Data to write
* @len: Maximum number of bytes to write
*/
size_t (*push)(StreamSlave *obj, unsigned char *buf, size_t len);
} StreamSlaveClass;
size_t
stream_push(StreamSlave *sink, uint8_t *buf, size_t len);
bool
stream_can_push(StreamSlave *sink, StreamCanPushNotifyFn notify,
void *notify_opaque);
#endif /* STREAM_H */