projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| b7cdc182 | 1 | /* SPDX-License-Identifier: (GPL-2.0-only OR LGPL-2.1-only) |
| 9f36eaed | 2 | * |
| 886d51a3 | 3 | * lib/ringbuffer/iterator.h |
| f3bc08c5 MD |
4 | * |
| 5 | * Ring buffer and channel iterators. | |
| 6 | * | |
| 886d51a3 | 7 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| f3bc08c5 MD |
8 | */ |
| 9 | ||
| 9f36eaed MJ |
10 | #ifndef _LIB_RING_BUFFER_ITERATOR_H |
| 11 | #define _LIB_RING_BUFFER_ITERATOR_H | |
| 12 | ||
| 5671a661 MD |
13 | #include <wrapper/ringbuffer/backend.h> |
| 14 | #include <wrapper/ringbuffer/frontend.h> | |
| 15 | #include <wrapper/ringbuffer/vfs.h> | |
| f3bc08c5 MD |
16 | |
| 17 | /* | |
| 18 | * lib_ring_buffer_get_next_record advances the buffer read position to the next | |
| 19 | * record. It returns either the size of the next record, -EAGAIN if there is | |
| 20 | * currently no data available, or -ENODATA if no data is available and buffer | |
| 21 | * is finalized. | |
| 22 | */ | |
| 23 | extern ssize_t lib_ring_buffer_get_next_record(struct channel *chan, | |
| 24 | struct lib_ring_buffer *buf); | |
| 25 | ||
| 26 | /* | |
| 27 | * channel_get_next_record advances the buffer read position to the next record. | |
| 28 | * It returns either the size of the next record, -EAGAIN if there is currently | |
| 29 | * no data available, or -ENODATA if no data is available and buffer is | |
| 30 | * finalized. | |
| 31 | * Returns the current buffer in ret_buf. | |
| 32 | */ | |
| 33 | extern ssize_t channel_get_next_record(struct channel *chan, | |
| 34 | struct lib_ring_buffer **ret_buf); | |
| 35 | ||
| 36 | /** | |
| 37 | * read_current_record - copy the buffer current record into dest. | |
| 38 | * @buf: ring buffer | |
| 39 | * @dest: destination where the record should be copied | |
| 40 | * | |
| 41 | * dest should be large enough to contain the record. Returns the number of | |
| 42 | * bytes copied. | |
| 43 | */ | |
| 44 | static inline size_t read_current_record(struct lib_ring_buffer *buf, void *dest) | |
| 45 | { | |
| 46 | return lib_ring_buffer_read(&buf->backend, buf->iter.read_offset, | |
| 47 | dest, buf->iter.payload_len); | |
| 48 | } | |
| 49 | ||
| 50 | extern int lib_ring_buffer_iterator_open(struct lib_ring_buffer *buf); | |
| 51 | extern void lib_ring_buffer_iterator_release(struct lib_ring_buffer *buf); | |
| 52 | extern int channel_iterator_open(struct channel *chan); | |
| 53 | extern void channel_iterator_release(struct channel *chan); | |
| 54 | ||
| 55 | extern const struct file_operations channel_payload_file_operations; | |
| 56 | extern const struct file_operations lib_ring_buffer_payload_file_operations; | |
| 57 | ||
| 58 | /* | |
| 59 | * Used internally. | |
| 60 | */ | |
| 61 | int channel_iterator_init(struct channel *chan); | |
| 62 | void channel_iterator_unregister_notifiers(struct channel *chan); | |
| 63 | void channel_iterator_free(struct channel *chan); | |
| 64 | void channel_iterator_reset(struct channel *chan); | |
| 65 | void lib_ring_buffer_iterator_reset(struct lib_ring_buffer *buf); | |
| 66 | ||
| 886d51a3 | 67 | #endif /* _LIB_RING_BUFFER_ITERATOR_H */ |