include/babeltrace/ctf-ir/event.h

   1 #ifndef BABELTRACE_CTF_IR_EVENT_H
   2 #define BABELTRACE_CTF_IR_EVENT_H
   3
   4 /*
   5  * BabelTrace - CTF IR: Event
   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 <stdint.h>
  34 #include <stddef.h>
  35 #include <babeltrace/values.h>
  36
  37 #ifdef __cplusplus
  38 extern "C" {
  39 #endif
  40
  41 /**
  42 @defgroup ctfirevent CTF IR event
  43 @ingroup ctfir
  44 @brief CTF IR event.
  45
  46 @code
  47 #include <babeltrace/ctf-ir/event.h>
  48 @endcode
  49
  50 A CTF IR <strong><em>event</em></strong> is a container of event
  51 fields:
  52
  53 - <strong>Stream event header</strong> field, described by the
  54   <em>stream event header field type</em> of a
  55   \link ctfirstreamclass CTF IR stream class\endlink.
  56 - <strong>Stream event context</strong> field, described by the
  57   <em>stream event context field type</em> of a stream class.
  58 - <strong>Event context</strong> field, described by the
  59   <em>event context field type</em> of a
  60   \link ctfireventclass CTF IR event class\endlink.
  61 - <strong>Event payload</strong>, described by the
  62   <em>event payload field type</em> of an event class.
  63
  64 As a reminder, here's the structure of a CTF packet:
  65
  66 @imgpacketstructure
  67
  68 You can create a CTF IR event \em from a
  69 \link ctfireventclass CTF IR event class\endlink with
  70 bt_ctf_event_create(). The event class you use to create an event
  71 object becomes its parent.
  72
  73 If the \link ctfirtraceclass CTF IR trace class\endlink of an event
  74 object (parent of its \link ctfirstreamclass CTF IR stream class\endlink,
  75 which is the parent of its event class) was created by a
  76 \link ctfirwriter CTF IR writer\endlink object, then the only possible
  77 action you can do with this event object is to append it to a
  78 \link ctfirstream CTF IR stream\endlink with
  79 bt_ctf_stream_append_event(). Otherwise, you can create an event
  80 notification with bt_notification_event_create(). The event you pass
  81 to this function \em must have an attached packet object first.
  82
  83 You can attach a \link ctfirpacket CTF IR packet object\endlink to an
  84 event object with bt_ctf_event_set_packet().
  85
  86 A CTF IR event has a mapping of
  87 \link ctfirclockvalue CTF IR clock values\endlink. A clock value is
  88 an instance of a specific
  89 \link ctfirclockclass CTF IR clock class\endlink when the event is
  90 emitted. You can set an event object's clock value with
  91 bt_ctf_event_set_clock_value().
  92
  93 As with any Babeltrace object, CTF IR event objects have
  94 <a href="https://en.wikipedia.org/wiki/Reference_counting">reference
  95 counts</a>. See \ref refs to learn more about the reference counting
  96 management of Babeltrace objects.
  97
  98 bt_notification_event_create() \em freezes its event parameter on
  99 success. You cannot modify a frozen event object: it is considered
 100 immutable, except for \link refs reference counting\endlink.
 101
 102 @sa ctfireventclass
 103 @sa ctfirpacket
 104
 105 @file
 106 @brief CTF IR event type and functions.
 107 @sa ctfirevent
 108
 109 @addtogroup ctfirevent
 110 @{
 111 */
 112
 113 /**
 114 @struct bt_ctf_event
 115 @brief A CTF IR event.
 116 @sa ctfirevent
 117 */
 118 struct bt_ctf_event;
 119 struct bt_ctf_clock;
 120 struct bt_ctf_clock_value;
 121 struct bt_ctf_event_class;
 122 struct bt_ctf_field;
 123 struct bt_ctf_field_type;
 124 struct bt_ctf_stream_class;
 125 struct bt_ctf_packet;
 126
 127 /**
 128 @name Creation and parent access functions
 129 @{
 130 */
 131
 132 /**
 133 @brief  Creates a default CTF IR event from the CTF IR event class
 134         \p event_class.
 135
 136 \p event_class \em must have a parent
 137 \link ctfirstreamclass CTF IR stream class\endlink.
 138
 139 On success, the four fields of the created event object are not set. You
 140 can set them with bt_ctf_event_set_header(),
 141 bt_ctf_event_set_stream_event_context(),
 142 bt_ctf_event_set_event_context(), and bt_ctf_event_set_payload_field().
 143
 144 @param[in] event_class  CTF IR event class to use to create the
 145                         CTF IR event.
 146 @returns                Created event object, or \c NULL on error.
 147
 148 @prenotnull{event_class}
 149 @pre \p event_class has a parent stream class.
 150 @postsuccessrefcountret1
 151 */
 152 extern struct bt_ctf_event *bt_ctf_event_create(
 153                 struct bt_ctf_event_class *event_class);
 154
 155 /**
 156 @brief  Returns the parent CTF IR event class of the CTF IR event
 157         \p event.
 158
 159 This function returns a reference to the event class which was used to
 160 create the event object in the first place with bt_ctf_event_create().
 161
 162 @param[in] event        Event of which to get the parent event class.
 163 @returns                Parent event class of \p event,
 164                         or \c NULL on error.
 165
 166 @prenotnull{event}
 167 @postrefcountsame{event}
 168 @postsuccessrefcountretinc
 169 */
 170 extern struct bt_ctf_event_class *bt_ctf_event_get_class(
 171                 struct bt_ctf_event *event);
 172
 173 /**
 174 @brief  Returns the CTF IR packet associated to the CTF IR event
 175         \p event.
 176
 177 This function returns a reference to the event class which was set to
 178 \p event in the first place with bt_ctf_event_set_packet().
 179
 180 @param[in] event        Event of which to get the associated packet.
 181 @returns                Packet associated to \p event,
 182                         or \c NULL if no packet is associated to
 183                         \p event or on error.
 184
 185 @prenotnull{event}
 186 @postrefcountsame{event}
 187 @postsuccessrefcountretinc
 188
 189 @sa bt_ctf_event_set_packet(): Associates a given event to a given
 190         packet.
 191 */
 192 extern struct bt_ctf_packet *bt_ctf_event_get_packet(
 193                 struct bt_ctf_event *event);
 194
 195 /**
 196 @brief  Associates the CTF IR event \p event to the CTF IR packet
 197         \p packet.
 198
 199 The \link ctfirstreamclass CTF IR stream class\endlink of the
 200 parent \link ctfirstream CTF IR stream\endlink of \p packet \em must
 201 be the same as the parent stream class of the
 202 \link ctfireventclass CTF IR event class\endlink returned
 203 by bt_ctf_event_get_class() for \p event.
 204
 205 You \em must call this function to create an event-packet association
 206 before you call bt_notification_event_create() with \p event.
 207
 208 On success, this function also sets the parent stream object of
 209 \p event to the parent stream of \p packet.
 210
 211 @param[in] event        Event to which to associate \p packet.
 212 @param[in] packet       Packet to associate to \p event.
 213 @returns                0 on success, or a negative value on error.
 214
 215 @prenotnull{event}
 216 @prenotnull{packet}
 217 @prehot{event}
 218 @pre The parent stream class of \p packet is the same as the parent
 219         stream class of \p event.
 220 @postsuccessrefcountretinc
 221
 222 @sa bt_ctf_event_get_packet(): Returns the associated packet of a
 223         given event object.
 224 */
 225 extern int bt_ctf_event_set_packet(struct bt_ctf_event *event,
 226                 struct bt_ctf_packet *packet);
 227
 228 /**
 229 @brief  Returns the parent CTF IR stream associated to the CTF IR event
 230         \p event.
 231
 232 @param[in] event        Event of which to get the parent stream.
 233 @returns                Parent stream of \p event, or \c NULL on error.
 234
 235 @prenotnull{event}
 236 @postrefcountsame{event}
 237 @postsuccessrefcountretinc
 238 */
 239 extern struct bt_ctf_stream *bt_ctf_event_get_stream(
 240                 struct bt_ctf_event *event);
 241
 242 /** @} */
 243
 244 /**
 245 @name Contained fields functions
 246 @{
 247 */
 248
 249 /**
 250 @brief  Returns the stream event header field of the CTF IR event
 251         \p event.
 252
 253 @param[in] event        Event of which to get the stream event header
 254                         field.
 255 @returns                Stream event header field of \p event,
 256                         or \c NULL if the stream event header
 257                         field is not set or on error.
 258
 259 @prenotnull{event}
 260 @postrefcountsame{event}
 261 @postsuccessrefcountretinc
 262
 263 @sa bt_ctf_event_get_header(): Sets the stream event header
 264         field of a given event.
 265 */
 266 extern struct bt_ctf_field *bt_ctf_event_get_header(
 267                 struct bt_ctf_event *event);
 268
 269 /**
 270 @brief  Sets the stream event header field of the CTF IR event
 271         \p event to \p header.
 272
 273 The field type of \p header, as returned by bt_ctf_field_get_type(),
 274 \em must be equivalent to the field type returned by
 275 bt_ctf_stream_class_get_event_header_type() for the parent stream class
 276 of \p event.
 277
 278 @param[in] event        Event of which to set the stream event header
 279                         field.
 280 @param[in] header       Stream event header field.
 281 @returns                0 on success, or a negative value on error.
 282
 283 @prenotnull{event}
 284 @prenotnull{header}
 285 @prehot{event}
 286 @pre \p header has a field type equivalent to the field type returned by
 287         bt_ctf_stream_class_get_event_header_type() for the parent
 288         stream class of \p event.
 289 @postrefcountsame{event}
 290 @postsuccessrefcountinc{header}
 291
 292 @sa bt_ctf_event_get_header(): Returns the stream event header field
 293         of a given event.
 294 */
 295 extern int bt_ctf_event_set_header(struct bt_ctf_event *event,
 296                 struct bt_ctf_field *header);
 297
 298 /**
 299 @brief  Returns the stream event context field of the CTF IR event
 300         \p event.
 301
 302 @param[in] event        Event of which to get the stream event context
 303                         field.
 304 @returns                Stream event context field of \p event,
 305                         or \c NULL if the stream event context
 306                         field is not set or on error.
 307
 308 @prenotnull{event}
 309 @postrefcountsame{event}
 310 @postsuccessrefcountretinc
 311
 312 @sa bt_ctf_event_set_stream_event_context(): Sets the stream event
 313         context field of a given event.
 314 */
 315 extern struct bt_ctf_field *bt_ctf_event_get_stream_event_context(
 316                 struct bt_ctf_event *event);
 317
 318 /**
 319 @brief  Sets the stream event context field of the CTF IR event
 320         \p event to \p context.
 321
 322 The field type of \p context, as returned by bt_ctf_field_get_type(),
 323 \em must be equivalent to the field type returned by
 324 bt_ctf_stream_class_get_event_context_type() for the parent stream class
 325 of \p event.
 326
 327 @param[in] event        Event of which to set the stream event context
 328                         field.
 329 @param[in] context      Stream event context field.
 330 @returns                0 on success, or a negative value on error.
 331
 332 @prenotnull{event}
 333 @prenotnull{context}
 334 @prehot{event}
 335 @pre \p context has a field type equivalent to the field type returned
 336         by bt_ctf_stream_class_get_event_context_type() for the parent
 337         stream class of \p event.
 338 @postrefcountsame{event}
 339 @postsuccessrefcountinc{context}
 340
 341 @sa bt_ctf_event_get_stream_event_context(): Returns the stream event
 342         context field of a given event.
 343 */
 344 extern int bt_ctf_event_set_stream_event_context(struct bt_ctf_event *event,
 345                 struct bt_ctf_field *context);
 346
 347 /**
 348 @brief  Returns the event context field of the CTF IR event
 349         \p event.
 350
 351 @param[in] event        Event of which to get the event context
 352                         field.
 353 @returns                Event context field of \p event, or \c NULL if
 354                         the event context field is not set or on error.
 355
 356 @prenotnull{event}
 357 @postrefcountsame{event}
 358 @postsuccessrefcountretinc
 359
 360 @sa bt_ctf_event_set_event_context(): Sets the event context field of a
 361         given event.
 362 */
 363 extern struct bt_ctf_field *bt_ctf_event_get_event_context(
 364                 struct bt_ctf_event *event);
 365
 366 /**
 367 @brief  Sets the event context field of the CTF IR event
 368         \p event to \p context.
 369
 370 The field type of \p context, as returned by bt_ctf_field_get_type(),
 371 \em must be equivalent to the field type returned by
 372 bt_ctf_event_class_get_context_type() for the parent event class
 373 of \p event.
 374
 375 @param[in] event        Event of which to set the event context field.
 376 @param[in] context      Event context field.
 377 @returns                0 on success, or a negative value on error.
 378
 379 @prenotnull{event}
 380 @prenotnull{context}
 381 @prehot{event}
 382 @pre \p context has a field type equivalent to the field type returned
 383         by bt_ctf_event_class_get_context_type() for the parent
 384         event class of \p event.
 385 @postrefcountsame{event}
 386 @postsuccessrefcountinc{context}
 387
 388 @sa bt_ctf_event_get_event_context(): Returns the event context field of
 389         a given event.
 390 */
 391 extern int bt_ctf_event_set_event_context(struct bt_ctf_event *event,
 392                 struct bt_ctf_field *context);
 393
 394 /**
 395 @brief  Returns the event payload field of the CTF IR event
 396         \p event.
 397
 398 @param[in] event        Event of which to get the event payload
 399                         field.
 400 @returns                Event payload field of \p event, or \c NULL if
 401                         the event payload field is not set or on error.
 402
 403 @prenotnull{event}
 404 @postrefcountsame{event}
 405 @postsuccessrefcountretinc
 406
 407 @sa bt_ctf_event_set_payload_field(): Sets the event payload field of a
 408         given event.
 409 */
 410 extern struct bt_ctf_field *bt_ctf_event_get_payload_field(
 411                 struct bt_ctf_event *event);
 412
 413 /**
 414 @brief  Sets the event payload field of the CTF IR event
 415         \p event to \p payload.
 416
 417 The field type of \p payload, as returned by bt_ctf_field_get_type(),
 418 \em must be equivalent to the field type returned by
 419 bt_ctf_event_class_get_payload_type() for the parent event class
 420 of \p event.
 421
 422 @param[in] event        Event of which to set the event payload field.
 423 @param[in] payload      Event payload field.
 424 @returns                0 on success, or a negative value on error.
 425
 426 @prenotnull{event}
 427 @prenotnull{payload}
 428 @prehot{event}
 429 @pre \p payload has a field type equivalent to the field type returned
 430         by bt_ctf_event_class_get_payload_type() for the parent
 431         event class of \p event.
 432 @postrefcountsame{event}
 433 @postsuccessrefcountinc{payload}
 434
 435 @sa bt_ctf_event_get_payload_field(): Returns the event payload field of
 436         a given event.
 437 */
 438 extern int bt_ctf_event_set_payload_field(struct bt_ctf_event *event,
 439                 struct bt_ctf_field *payload);
 440
 441 /**
 442 @cond DOCUMENT
 443 */
 444
 445 /*
 446  * TODO: Doxygenize.
 447  *
 448  * bt_ctf_event_get_payload: get an event's field.
 449  *
 450  * Returns the field matching "name". bt_put() must be called on the
 451  * returned value.
 452  *
 453  * @param event Event instance.
 454  * @param name Event field name, see notes.
 455  *
 456  * Returns a field instance on success, NULL on error.
 457  *
 458  * Note: Passing a name will cause the function to perform a look-up by
 459  *      name assuming the event's payload is a structure. This will return
 460  *      the raw payload instance if name is NULL.
 461  */
 462 extern struct bt_ctf_field *bt_ctf_event_get_payload(struct bt_ctf_event *event,
 463                 const char *name);
 464
 465 /*
 466  * TODO: Doxygenize.
 467  *
 468  * bt_ctf_event_get_payload_by_index: Get event's field by index.
 469  *
 470  * Returns the field associated with the provided index. bt_put()
 471  * must be called on the returned value. The indexes to be provided are
 472  * the same as can be retrieved from the event class.
 473  *
 474  * @param event Event.
 475  * @param index Index of field.
 476  *
 477  * Returns the event's field, NULL on error.
 478  *
 479  * Note: Will return an error if the payload's type is not a structure.
 480  */
 481 extern struct bt_ctf_field *bt_ctf_event_get_payload_by_index(
 482                 struct bt_ctf_event *event, int index);
 483
 484 /*
 485  * TODO: Doxygenize.
 486  *
 487  * bt_ctf_event_set_payload: set an event's field.
 488  *
 489  * Set a manually allocated field as an event's payload. The event will share
 490  * the field's ownership by using its reference count.
 491  * bt_put() must be called on the returned value.
 492  *
 493  * @param event Event instance.
 494  * @param name Event field name, see notes.
 495  * @param value Instance of a field whose type corresponds to the event's field.
 496  *
 497  * Returns 0 on success, a negative value on error.
 498  *
 499  * Note: The function will return an error if a name is provided and the payload
 500  *      type is not a structure. If name is NULL, the payload field will be set
 501  *      directly and must match the event class' payload's type.
 502  */
 503 extern int bt_ctf_event_set_payload(struct bt_ctf_event *event,
 504                 const char *name,
 505                 struct bt_ctf_field *value);
 506
 507 /**
 508 @endcond
 509 */
 510
 511 /** @} */
 512
 513 /**
 514 @name Clock value functions
 515 @{
 516 */
 517
 518 /**
 519 @brief  Returns the value, as of the CTF IR event \p event, of the
 520         clock described by the
 521         \link ctfirclockclass CTF IR clock class\endlink \p clock_class.
 522
 523 @param[in] event        Event of which to get the value of the clock
 524                         described by \p clock_class.
 525 @param[in] clock_class  Class of the clock of which to get the value.
 526 @returns                Value of the clock described by \p clock_class
 527                         as of \p event.
 528
 529 @prenotnull{event}
 530 @prenotnull{clock_class}
 531 @postrefcountsame{event}
 532 @postrefcountsame{clock_class}
 533 @postsuccessrefcountretinc
 534
 535 @sa bt_ctf_event_set_clock_value(): Sets the clock value of a given event.
 536 */
 537 extern struct bt_ctf_clock_value *bt_ctf_event_get_clock_value(
 538                 struct bt_ctf_event *event, struct bt_ctf_clock *clock_class);
 539
 540 /**
 541 @brief  Sets the value, as of the CTF IR event \p event, of the
 542         clock described by the
 543         \link ctfirclockclass CTF IR clock class\endlink \p clock_class.
 544
 545 @param[in] event        Event of which to set the value of the clock
 546                         described by \p clock_class.
 547 @param[in] clock_class  Class of the clock of which to set the value
 548                         for \p event.
 549 @param[in] clock_value  Value of the clock described by \p clock_class
 550                         as of \p event.
 551 @returns                0 on success, or a negative value on error.
 552
 553 @prenotnull{event}
 554 @prenotnull{clock_class}
 555 @prenotnull{clock_value}
 556 @prehot{event}
 557 @postrefcountsame{event}
 558 @postrefcountsame{clock_class}
 559
 560 @sa bt_ctf_event_get_clock_value(): Returns the clock value of
 561         a given event.
 562 */
 563 extern int bt_ctf_event_set_clock_value(
 564                 struct bt_ctf_event *event, struct bt_ctf_clock *clock_class,
 565                 struct bt_ctf_clock_value *clock_value);
 566
 567 /** @} */
 568
 569 /** @} */
 570
 571 #ifdef __cplusplus
 572 }
 573 #endif
 574
 575 #endif /* BABELTRACE_CTF_IR_EVENT_H */