lib/babeltrace/ctf-ir/stream-class.h

   1 #ifndef BABELTRACE_CTF_IR_STREAM_CLASS_H
   2 #define BABELTRACE_CTF_IR_STREAM_CLASS_H
   3
   4 /*
   5  * BabelTrace - CTF IR: Stream Class
   6  *
   7  * Copyright 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 #ifdef __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 struct bt_ctf_event_class;
  38 struct bt_ctf_stream_class;
  39 struct bt_ctf_clock;
  40
  41 /*
  42  * bt_ctf_stream_class_create: create a stream class.
  43  *
  44  * Allocate a new stream class of the given name. The creation of an event class
  45  * sets its reference count to 1.
  46  *
  47  * A stream class' packet context is a structure initialized with the following
  48  * fields:
  49  *      - uint64_t timestamp_begin
  50  *      - uint64_t timestamp_end
  51  *      - uint64_t content_size
  52  *      - uint64_t packet_size
  53  *      - uint64_t events_discarded
  54  *
  55  * @param name Stream name.
  56  *
  57  * Returns an allocated stream class on success, NULL on error.
  58  */
  59 extern struct bt_ctf_stream_class *bt_ctf_stream_class_create(const char *name);
  60
  61 /*
  62  * bt_ctf_stream_class_get_name: Get a stream class' name.
  63  *
  64  * @param stream_class Stream class.
  65  *
  66  * Returns the stream class' name, NULL on error.
  67  */
  68 extern const char *bt_ctf_stream_class_get_name(
  69                 struct bt_ctf_stream_class *stream_class);
  70
  71 /*
  72  * bt_ctf_stream_class_get_clock: get the clock associated with a stream class.
  73  *
  74  * @param stream_class Stream class.
  75  *
  76  * Returns a clock instance, NULL on error.
  77  */
  78 extern struct bt_ctf_clock *bt_ctf_stream_class_get_clock(
  79                 struct bt_ctf_stream_class *stream_class);
  80
  81 /*
  82  * bt_ctf_stream_class_set_clock: assign a clock to a stream class.
  83  *
  84  * Assign a clock to a stream class. This clock will be sampled each time an
  85  * event is appended to an instance of this stream class.
  86  *
  87  * @param stream_class Stream class.
  88  * @param clock Clock to assign to the provided stream class.
  89  *
  90  * Returns 0 on success, a negative value on error.
  91  */
  92 extern int bt_ctf_stream_class_set_clock(
  93                 struct bt_ctf_stream_class *stream_class,
  94                 struct bt_ctf_clock *clock);
  95
  96 /*
  97  * bt_ctf_stream_class_get_id: Get a stream class' id.
  98  *
  99  * @param stream_class Stream class.
 100  *
 101  * Returns the stream class' id, a negative value on error.
 102  */
 103 extern int64_t bt_ctf_stream_class_get_id(
 104                 struct bt_ctf_stream_class *stream_class);
 105
 106 /*
 107  * bt_ctf_stream_class_set_id: Set a stream class' id.
 108  *
 109  * Set a stream class' id. Must be unique trace-wise.
 110  * Note that stream classes are assigned a unique id when a stream instance
 111  * is created for the first time from a trace or writer.
 112  *
 113  * @param stream_class Stream class.
 114  * @param id Stream class id.
 115  *
 116  * Returns 0 on success, a negative value on error.
 117  */
 118 extern int bt_ctf_stream_class_set_id(
 119                 struct bt_ctf_stream_class *stream_class, uint32_t id);
 120
 121 /*
 122  * bt_ctf_stream_class_set_clock: assign a clock to a stream class.
 123  *
 124  * Add an event class to a stream class. New events can be added even after a
 125  * stream has beem instanciated and events have been appended. However, a stream
 126  * will not accept events of a class that has not been registered beforehand.
 127  * The stream class will share the ownership of "event_class" by incrementing
 128  * its reference count.
 129  *
 130  * @param stream_class Stream class.
 131  * @param event_class Event class to add to the provided stream class.
 132  *
 133  * Returns 0 on success, a negative value on error.
 134  */
 135 extern int bt_ctf_stream_class_add_event_class(
 136                 struct bt_ctf_stream_class *stream_class,
 137                 struct bt_ctf_event_class *event_class);
 138
 139 /*
 140  * bt_ctf_stream_class_get_event_class_count: Get a stream class' event class
 141  * count.
 142  *
 143  * @param stream_class Stream class.
 144  *
 145  * Returns the stream class' event count, a negative value on error.
 146  */
 147 extern int64_t bt_ctf_stream_class_get_event_class_count(
 148                 struct bt_ctf_stream_class *stream_class);
 149
 150 /*
 151  * bt_ctf_stream_class_get_event_class: Get stream class event class by index.
 152  *
 153  * @param stream_class Stream class.
 154  * @param index Index of field.
 155  *
 156  * Returns event class, NULL on error.
 157  */
 158 extern struct bt_ctf_event_class *bt_ctf_stream_class_get_event_class(
 159                 struct bt_ctf_stream_class *stream_class, size_t index);
 160
 161 /*
 162  * bt_ctf_stream_class_get_event_class_by_name: Get stream class event class by
 163  * name.
 164  *
 165  * @param stream_class Stream class.
 166  * @param name Event name.
 167  *
 168  * Returns event class, NULL on error.
 169  */
 170 extern struct bt_ctf_event_class *bt_ctf_stream_class_get_event_class_by_name(
 171                 struct bt_ctf_stream_class *stream_class, const char *name);
 172
 173 /*
 174  * bt_ctf_stream_class_get_packet_context_type: get the stream class' packet
 175  * context type.
 176  *
 177  * @param stream_class Stream class.
 178  *
 179  * Returns the packet context's type, NULL on error.
 180  */
 181 extern struct bt_ctf_field_type *bt_ctf_stream_class_get_packet_context_type(
 182                 struct bt_ctf_stream_class *stream_class);
 183
 184 /*
 185  * bt_ctf_stream_class_set_packet_context_type: set the stream class' packet
 186  * context type.
 187  *
 188  * @param stream_class Stream class.
 189  *
 190  * Returns 0 on success, a negative value on error.
 191  */
 192 extern int bt_ctf_stream_class_set_packet_context_type(
 193                 struct bt_ctf_stream_class *stream_class,
 194                 struct bt_ctf_field_type *packet_context_type);
 195
 196 /*
 197  * bt_ctf_stream_class_get and bt_ctf_stream_class_put: increment and
 198  * decrement the stream class' reference count.
 199  *
 200  * These functions ensure that the stream class won't be destroyed while it
 201  * is in use. The same number of get and put (plus one extra put to
 202  * release the initial reference done at creation) have to be done to
 203  * destroy a stream class.
 204  *
 205  * When the stream class' reference count is decremented to 0 by a
 206  * bt_ctf_stream_class_put, the stream class is freed.
 207  *
 208  * @param stream_class Stream class.
 209  */
 210 extern void bt_ctf_stream_class_get(struct bt_ctf_stream_class *stream_class);
 211 extern void bt_ctf_stream_class_put(struct bt_ctf_stream_class *stream_class);
 212
 213 #ifdef __cplusplus
 214 }
 215 #endif
 216
 217 #endif /* BABELTRACE_CTF_IR_STREAM_CLASS_H */