include/babeltrace/ctf-ir/stream.h

   1 #ifndef BABELTRACE_CTF_IR_STREAM_H
   2 #define BABELTRACE_CTF_IR_STREAM_H
   3
   4 /*
   5  * BabelTrace - CTF IR: 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-ir/stream-class.h>
  34 #include <stdint.h>
  35
  36 #ifdef __cplusplus
  37 extern "C" {
  38 #endif
  39
  40 struct bt_ctf_event;
  41 struct bt_ctf_stream;
  42
  43 /*
  44  * bt_ctf_stream_get_stream_class: get a stream's class.
  45  *
  46  * @param stream Stream instance.
  47  *
  48  * Returns the stream's class, NULL on error.
  49  */
  50 extern struct bt_ctf_stream_class *bt_ctf_stream_get_class(
  51                 struct bt_ctf_stream *stream);
  52
  53 /*
  54  * bt_ctf_stream_get_discarded_events_count: get the number of discarded
  55  * events associated with this stream.
  56  *
  57  * Note that discarded events are not stored if the stream's packet
  58  * context has no "events_discarded" field. An error will be returned
  59  * in that case.
  60  *
  61  * @param stream Stream instance.
  62  *
  63  * Returns the number of discarded events, a negative value on error.
  64  */
  65 extern int bt_ctf_stream_get_discarded_events_count(
  66                 struct bt_ctf_stream *stream, uint64_t *count);
  67
  68 /*
  69  * bt_ctf_stream_append_discarded_events: increment discarded events count.
  70  *
  71  * Increase the current packet's discarded event count. Has no effect if the
  72  * stream class' packet context has no "events_discarded" field.
  73  *
  74  * @param stream Stream instance.
  75  * @param event_count Number of discarded events to add to the stream's current
  76  *      packet.
  77  */
  78 extern void bt_ctf_stream_append_discarded_events(struct bt_ctf_stream *stream,
  79                 uint64_t event_count);
  80
  81 /*
  82  * bt_ctf_stream_append_event: append an event to the stream.
  83  *
  84  * Append "event" to the stream's current packet. The stream's associated clock
  85  * will be sampled during this call. The event shall not be modified after
  86  * being appended to a stream. The stream will share the event's ownership by
  87  * incrementing its reference count. The current packet is not flushed to disk
  88  * until the next call to bt_ctf_stream_flush.
  89  *
  90  * The stream event context will be sampled for every appended event if
  91  * a stream event context was defined.
  92  *
  93  * @param stream Stream instance.
  94  * @param event Event instance to append to the stream's current packet.
  95  *
  96  * Returns 0 on success, a negative value on error.
  97  */
  98 extern int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
  99                 struct bt_ctf_event *event);
 100
 101 /*
 102  * bt_ctf_stream_get_packet_header: get a stream's packet header.
 103  *
 104  * @param stream Stream instance.
 105  *
 106  * Returns a field instance on success, NULL on error.
 107  */
 108 extern struct bt_ctf_field *bt_ctf_stream_get_packet_header(
 109                 struct bt_ctf_stream *stream);
 110
 111 /*
 112  * bt_ctf_stream_set_packet_header: set a stream's packet header.
 113  *
 114  * The packet header's type must match the trace's packet header
 115  * type.
 116  *
 117  * @param stream Stream instance.
 118  * @param packet_header Packet header instance.
 119  *
 120  * Returns a field instance on success, NULL on error.
 121  */
 122 extern int bt_ctf_stream_set_packet_header(
 123                 struct bt_ctf_stream *stream,
 124                 struct bt_ctf_field *packet_header);
 125
 126 /*
 127  * bt_ctf_stream_get_packet_context: get a stream's packet context.
 128  *
 129  * @param stream Stream instance.
 130  *
 131  * Returns a field instance on success, NULL on error.
 132  */
 133 extern struct bt_ctf_field *bt_ctf_stream_get_packet_context(
 134                 struct bt_ctf_stream *stream);
 135
 136 /*
 137  * bt_ctf_stream_set_packet_context: set a stream's packet context.
 138  *
 139  * The packet context's type must match the stream class' packet
 140  * context type.
 141  *
 142  * @param stream Stream instance.
 143  * @param packet_context Packet context field instance.
 144  *
 145  * Returns a field instance on success, NULL on error.
 146  */
 147 extern int bt_ctf_stream_set_packet_context(
 148                 struct bt_ctf_stream *stream,
 149                 struct bt_ctf_field *packet_context);
 150
 151 /*
 152  * bt_ctf_stream_flush: flush a stream.
 153  *
 154  * The stream's current packet's events will be flushed, thus closing the
 155  * current packet. Events subsequently appended to the stream will be
 156  * added to a new packet.
 157  *
 158  * Flushing will also set the packet context's default attributes if
 159  * they remained unset while populating the current packet. These default
 160  * attributes, along with their expected types, are detailed in stream-class.h.
 161  *
 162  * @param stream Stream instance.
 163  *
 164  * Returns 0 on success, a negative value on error.
 165  */
 166 extern int bt_ctf_stream_flush(struct bt_ctf_stream *stream);
 167
 168 /*
 169  * bt_ctf_stream_get and bt_ctf_stream_put: increment and decrement the
 170  * stream's reference count.
 171  *
 172  * You may also use bt_ctf_get() and bt_ctf_put() with stream objects.
 173  *
 174  * These functions ensure that the stream won't be destroyed while it
 175  * is in use. The same number of get and put (plus one extra put to
 176  * release the initial reference done at creation) have to be done to
 177  * destroy a stream.
 178  *
 179  * When the stream's reference count is decremented to 0 by a
 180  * bt_ctf_stream_put, the stream is freed.
 181  *
 182  * @param stream Stream instance.
 183  */
 184 extern void bt_ctf_stream_get(struct bt_ctf_stream *stream);
 185 extern void bt_ctf_stream_put(struct bt_ctf_stream *stream);
 186
 187 #ifdef __cplusplus
 188 }
 189 #endif
 190
 191 #endif /* BABELTRACE_CTF_IR_STREAM_H */