projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| f3bc08c5 MD |
1 | #ifndef _LINUX_RING_BUFFER_ITERATOR_H |
| 2 | #define _LINUX_RING_BUFFER_ITERATOR_H | |
| 3 | ||
| 4 | /* | |
| 5 | * linux/ringbuffer/iterator.h | |
| 6 | * | |
| 7 | * (C) Copyright 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 8 | * | |
| 9 | * Ring buffer and channel iterators. | |
| 10 | * | |
| 11 | * Author: | |
| 12 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 13 | * | |
| 14 | * Dual LGPL v2.1/GPL v2 license. | |
| 15 | */ | |
| 16 | ||
| 17 | #include "../../wrapper/ringbuffer/backend.h" | |
| 18 | #include "../../wrapper/ringbuffer/frontend.h" | |
| 19 | ||
| 20 | /* | |
| 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 | |
| 24 | * is finalized. | |
| 25 | */ | |
| 26 | extern ssize_t lib_ring_buffer_get_next_record(struct channel *chan, | |
| 27 | struct lib_ring_buffer *buf); | |
| 28 | ||
| 29 | /* | |
| 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 | |
| 33 | * finalized. | |
| 34 | * Returns the current buffer in ret_buf. | |
| 35 | */ | |
| 36 | extern ssize_t channel_get_next_record(struct channel *chan, | |
| 37 | struct lib_ring_buffer **ret_buf); | |
| 38 | ||
| 39 | /** | |
| 40 | * read_current_record - copy the buffer current record into dest. | |
| 41 | * @buf: ring buffer | |
| 42 | * @dest: destination where the record should be copied | |
| 43 | * | |
| 44 | * dest should be large enough to contain the record. Returns the number of | |
| 45 | * bytes copied. | |
| 46 | */ | |
| 47 | static inline size_t read_current_record(struct lib_ring_buffer *buf, void *dest) | |
| 48 | { | |
| 49 | return lib_ring_buffer_read(&buf->backend, buf->iter.read_offset, | |
| 50 | dest, buf->iter.payload_len); | |
| 51 | } | |
| 52 | ||
| 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); | |
| 57 | ||
| 58 | extern const struct file_operations channel_payload_file_operations; | |
| 59 | extern const struct file_operations lib_ring_buffer_payload_file_operations; | |
| 60 | ||
| 61 | /* | |
| 62 | * Used internally. | |
| 63 | */ | |
| 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); | |
| 69 | ||
| 70 | #endif /* _LINUX_RING_BUFFER_ITERATOR_H */ |