1 #ifndef _LINUX_RING_BUFFER_ITERATOR_H
2 #define _LINUX_RING_BUFFER_ITERATOR_H
5 * linux/ringbuffer/iterator.h
7 * (C) Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
9 * Ring buffer and channel iterators.
12 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
14 * Dual LGPL v2.1/GPL v2 license.
17 #include "../../wrapper/ringbuffer/backend.h"
18 #include "../../wrapper/ringbuffer/frontend.h"
21 * lib_ring_buffer_get_next_record advances the buffer read position to the next
22 * record. It returns either the size of the next record, -EAGAIN if there is
23 * currently no data available, or -ENODATA if no data is available and buffer
26 extern ssize_t
lib_ring_buffer_get_next_record(struct channel
*chan
,
27 struct lib_ring_buffer
*buf
);
30 * channel_get_next_record advances the buffer read position to the next record.
31 * It returns either the size of the next record, -EAGAIN if there is currently
32 * no data available, or -ENODATA if no data is available and buffer is
34 * Returns the current buffer in ret_buf.
36 extern ssize_t
channel_get_next_record(struct channel
*chan
,
37 struct lib_ring_buffer
**ret_buf
);
40 * read_current_record - copy the buffer current record into dest.
42 * @dest: destination where the record should be copied
44 * dest should be large enough to contain the record. Returns the number of
47 static inline size_t read_current_record(struct lib_ring_buffer
*buf
, void *dest
)
49 return lib_ring_buffer_read(&buf
->backend
, buf
->iter
.read_offset
,
50 dest
, buf
->iter
.payload_len
);
53 extern int lib_ring_buffer_iterator_open(struct lib_ring_buffer
*buf
);
54 extern void lib_ring_buffer_iterator_release(struct lib_ring_buffer
*buf
);
55 extern int channel_iterator_open(struct channel
*chan
);
56 extern void channel_iterator_release(struct channel
*chan
);
58 extern const struct file_operations channel_payload_file_operations
;
59 extern const struct file_operations lib_ring_buffer_payload_file_operations
;
64 int channel_iterator_init(struct channel
*chan
);
65 void channel_iterator_unregister_notifiers(struct channel
*chan
);
66 void channel_iterator_free(struct channel
*chan
);
67 void channel_iterator_reset(struct channel
*chan
);
68 void lib_ring_buffer_iterator_reset(struct lib_ring_buffer
*buf
);
70 #endif /* _LINUX_RING_BUFFER_ITERATOR_H */