include/babeltrace/ctf-writer/stream.h

   1 #ifndef BABELTRACE_CTF_WRITER_STREAM_H
   2 #define BABELTRACE_CTF_WRITER_STREAM_H
   3
   4 /*
   5  * BabelTrace - CTF Writer: Stream
   6  *
   7  * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   8  *
   9  * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  *
  29  * The Common Trace Format (CTF) Specification is available at
  30  * http://www.efficios.com/ctf
  31  */
  32
  33 #include <babeltrace/ctf-writer/stream-class.h>
  34
  35 struct bt_ctf_stream;
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 /*
  42  * bt_ctf_stream_append_discarded_events: increment discarded events count.
  43  *
  44  * Increase the current packet's discarded event count. Has no effect if the
  45  * stream class' packet context has no "events_discarded" field.
  46  *
  47  * @param stream Stream instance.
  48  * @param event_count Number of discarded events to add to the stream's current
  49  *      packet.
  50  */
  51 extern void bt_ctf_stream_append_discarded_events(struct bt_ctf_stream *stream,
  52                 uint64_t event_count);
  53
  54 /*
  55  * bt_ctf_stream_append_event: append an event to the stream.
  56  *
  57  * Append "event" to the stream's current packet. The stream's associated clock
  58  * will be sampled during this call. The event shall not be modified after
  59  * being appended to a stream. The stream will share the event's ownership by
  60  * incrementing its reference count. The current packet is not flushed to disk
  61  * until the next call to bt_ctf_stream_flush.
  62  *
  63  * The stream event context will be sampled for every appended event if
  64  * a stream event context was defined.
  65  *
  66  * @param stream Stream instance.
  67  * @param event Event instance to append to the stream's current packet.
  68  *
  69  * Returns 0 on success, a negative value on error.
  70  */
  71 extern int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
  72                 struct bt_ctf_event *event);
  73
  74 /*
  75  * bt_ctf_stream_get_packet_context: get a stream's packet context.
  76  *
  77  * @param stream Stream instance.
  78  *
  79  * Returns a field instance on success, NULL on error.
  80  */
  81 extern struct bt_ctf_field *bt_ctf_stream_get_packet_context(
  82                 struct bt_ctf_stream *stream);
  83
  84 /*
  85  * bt_ctf_stream_flush: flush a stream.
  86  *
  87  * The stream's current packet's events will be flushed, thus closing the
  88  * current packet. Events subsequently appended to the stream will be
  89  * added to a new packet.
  90  *
  91  * Flushing will also set the packet context's default attributes if
  92  * they remained unset while populating the current packet. These default
  93  * attributes, along with their expected types, are detailed in stream-class.h.
  94  *
  95  * @param stream Stream instance.
  96  *
  97  * Returns 0 on success, a negative value on error.
  98  */
  99 extern int bt_ctf_stream_flush(struct bt_ctf_stream *stream);
 100
 101 /*
 102  * bt_ctf_stream_get and bt_ctf_stream_put: increment and decrement the
 103  * stream's reference count.
 104  *
 105  * You may also use bt_ctf_get() and bt_ctf_put() with stream objects.
 106  *
 107  * These functions ensure that the stream won't be destroyed while it
 108  * is in use. The same number of get and put (plus one extra put to
 109  * release the initial reference done at creation) have to be done to
 110  * destroy a stream.
 111  *
 112  * When the stream's reference count is decremented to 0 by a
 113  * bt_ctf_stream_put, the stream is freed.
 114  *
 115  * @param stream Stream instance.
 116  */
 117 extern void bt_ctf_stream_get(struct bt_ctf_stream *stream);
 118 extern void bt_ctf_stream_put(struct bt_ctf_stream *stream);
 119
 120 #ifdef __cplusplus
 121 }
 122 #endif
 123
 124 #endif /* BABELTRACE_CTF_WRITER_STREAM_H */