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
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 struct bt_ctf_event;
  40 struct bt_ctf_stream;
  41
  42 /*
  43  * bt_ctf_stream_get_stream_class: get a stream's class.
  44  *
  45  * @param stream Stream instance.
  46  *
  47  * Returns the stream's class, NULL on error.
  48  */
  49 extern struct bt_ctf_stream_class *bt_ctf_stream_get_class(
  50                 struct bt_ctf_stream *stream);
  51
  52 /*
  53  * bt_ctf_stream_get_discarded_events_count: get the number of discarded
  54  * events associated with this stream.
  55  *
  56  * Note that discarded events are not stored if the stream's packet
  57  * context has no "events_discarded" field. An error will be returned
  58  * in that case.
  59  *
  60  * @param stream Stream instance.
  61  *
  62  * Returns the number of discarded events, a negative value on error.
  63  */
  64 extern int bt_ctf_stream_get_discarded_events_count(
  65                 struct bt_ctf_stream *stream, uint64_t *count);
  66
  67 /*
  68  * bt_ctf_stream_append_discarded_events: increment discarded events count.
  69  *
  70  * Increase the current packet's discarded event count. Has no effect if the
  71  * stream class' packet context has no "events_discarded" field.
  72  *
  73  * @param stream Stream instance.
  74  * @param event_count Number of discarded events to add to the stream's current
  75  *      packet.
  76  */
  77 extern void bt_ctf_stream_append_discarded_events(struct bt_ctf_stream *stream,
  78                 uint64_t event_count);
  79
  80 /*
  81  * bt_ctf_stream_append_event: append an event to the stream.
  82  *
  83  * Append "event" to the stream's current packet. The stream's associated clock
  84  * will be sampled during this call. The event shall not be modified after
  85  * being appended to a stream. The stream will share the event's ownership by
  86  * incrementing its reference count. The current packet is not flushed to disk
  87  * until the next call to bt_ctf_stream_flush.
  88  *
  89  * The stream event context will be sampled for every appended event if
  90  * a stream event context was defined.
  91  *
  92  * @param stream Stream instance.
  93  * @param event Event instance to append to the stream's current packet.
  94  *
  95  * Returns 0 on success, a negative value on error.
  96  */
  97 extern int bt_ctf_stream_append_event(struct bt_ctf_stream *stream,
  98                 struct bt_ctf_event *event);
  99
 100 /*
 101  * bt_ctf_stream_get_packet_header: get a stream's packet header.
 102  *
 103  * @param stream Stream instance.
 104  *
 105  * Returns a field instance on success, NULL on error.
 106  */
 107 extern struct bt_ctf_field *bt_ctf_stream_get_packet_header(
 108                 struct bt_ctf_stream *stream);
 109
 110 /*
 111  * bt_ctf_stream_set_packet_header: set a stream's packet header.
 112  *
 113  * The packet header's type must match the trace's packet header
 114  * type.
 115  *
 116  * @param stream Stream instance.
 117  * @param packet_header Packet header instance.
 118  *
 119  * Returns a field instance on success, NULL on error.
 120  */
 121 extern int bt_ctf_stream_set_packet_header(
 122                 struct bt_ctf_stream *stream,
 123                 struct bt_ctf_field *packet_header);
 124
 125 /*
 126  * bt_ctf_stream_get_packet_context: get a stream's packet context.
 127  *
 128  * @param stream Stream instance.
 129  *
 130  * Returns a field instance on success, NULL on error.
 131  */
 132 extern struct bt_ctf_field *bt_ctf_stream_get_packet_context(
 133                 struct bt_ctf_stream *stream);
 134
 135 /*
 136  * bt_ctf_stream_set_packet_context: set a stream's packet context.
 137  *
 138  * The packet context's type must match the stream class' packet
 139  * context type.
 140  *
 141  * @param stream Stream instance.
 142  * @param packet_context Packet context field instance.
 143  *
 144  * Returns a field instance on success, NULL on error.
 145  */
 146 extern int bt_ctf_stream_set_packet_context(
 147                 struct bt_ctf_stream *stream,
 148                 struct bt_ctf_field *packet_context);
 149
 150 /*
 151  * bt_ctf_stream_get_event_header: get a stream's event header.
 152  *
 153  * @param stream Stream instance.
 154  *
 155  * Returns a field instance on success, NULL on error.
 156  */
 157 extern struct bt_ctf_field *bt_ctf_stream_get_event_header(
 158                 struct bt_ctf_stream *stream);
 159
 160 /*
 161  * bt_ctf_stream_set_event_header: set a stream's event header.
 162  *
 163  * The event header's type must match the stream class' event
 164  * header type.
 165  *
 166  * @param stream Stream instance.
 167  * @param event_header Event header field instance.
 168  *
 169  * Returns a field instance on success, NULL on error.
 170  */
 171 extern int bt_ctf_stream_set_event_context(
 172                 struct bt_ctf_stream *stream,
 173                 struct bt_ctf_field *event_context);
 174
 175 /*
 176  * bt_ctf_stream_get_event_context: get a stream's event context.
 177  *
 178  * @param stream Stream instance.
 179  *
 180  * Returns a field instance on success, NULL on error.
 181  */
 182 extern struct bt_ctf_field *bt_ctf_stream_get_event_context(
 183                 struct bt_ctf_stream *stream);
 184
 185 /*
 186  * bt_ctf_stream_set_event_context: set a stream's event context.
 187  *
 188  * The event context's type must match the stream class' event
 189  * context type.
 190  *
 191  * @param stream Stream instance.
 192  * @param event_context Event context field instance.
 193  *
 194  * Returns a field instance on success, NULL on error.
 195  */
 196 extern int bt_ctf_stream_set_event_context(
 197                 struct bt_ctf_stream *stream,
 198                 struct bt_ctf_field *event_context);
 199
 200 /*
 201  * bt_ctf_stream_flush: flush a stream.
 202  *
 203  * The stream's current packet's events will be flushed, thus closing the
 204  * current packet. Events subsequently appended to the stream will be
 205  * added to a new packet.
 206  *
 207  * Flushing will also set the packet context's default attributes if
 208  * they remained unset while populating the current packet. These default
 209  * attributes, along with their expected types, are detailed in stream-class.h.
 210  *
 211  * @param stream Stream instance.
 212  *
 213  * Returns 0 on success, a negative value on error.
 214  */
 215 extern int bt_ctf_stream_flush(struct bt_ctf_stream *stream);
 216
 217 /*
 218  * bt_ctf_stream_get and bt_ctf_stream_put: increment and decrement the
 219  * stream's reference count.
 220  *
 221  * These functions ensure that the stream won't be destroyed while it
 222  * is in use. The same number of get and put (plus one extra put to
 223  * release the initial reference done at creation) have to be done to
 224  * destroy a stream.
 225  *
 226  * When the stream's reference count is decremented to 0 by a
 227  * bt_ctf_stream_put, the stream is freed.
 228  *
 229  * @param stream Stream instance.
 230  */
 231 extern void bt_ctf_stream_get(struct bt_ctf_stream *stream);
 232 extern void bt_ctf_stream_put(struct bt_ctf_stream *stream);
 233
 234 #ifdef __cplusplus
 235 }
 236 #endif
 237
 238 #endif /* BABELTRACE_CTF_IR_STREAM_H */