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 This function tries to resolve the needed
 145 \link ctfirfieldtypes CTF IR field type\endlink of the dynamic field
 146 types that are found anywhere in the context or payload field
 147 types of \p event_class and in the root field types of the
 148 parent stream class of \p event_class. If any automatic resolving fails,
 149 this function fails. This means that, if any dynamic field type need
 150 a field type which should be found in the trace packet header root
 151 field type, and if the parent stream class of \p event_class was not
 152 added to a \link ctfirtraceclass CTF IR trace class\endlink yet
 153 with bt_ctf_trace_add_stream_class(), then this function fails.
 154
 155 @param[in] event_class  CTF IR event class to use to create the
 156                         CTF IR event.
 157 @returns                Created event object, or \c NULL on error.
 158
 159 @prenotnull{event_class}
 160 @pre \p event_class has a parent stream class.
 161 @postsuccessrefcountret1
 162 */
 163 extern struct bt_ctf_event *bt_ctf_event_create(
 164                 struct bt_ctf_event_class *event_class);
 165
 166 /**
 167 @brief  Returns the parent CTF IR event class of the CTF IR event
 168         \p event.
 169
 170 This function returns a reference to the event class which was used to
 171 create the event object in the first place with bt_ctf_event_create().
 172
 173 @param[in] event        Event of which to get the parent event class.
 174 @returns                Parent event class of \p event,
 175                         or \c NULL on error.
 176
 177 @prenotnull{event}
 178 @postrefcountsame{event}
 179 @postsuccessrefcountretinc
 180 */
 181 extern struct bt_ctf_event_class *bt_ctf_event_get_class(
 182                 struct bt_ctf_event *event);
 183
 184 /**
 185 @brief  Returns the CTF IR packet associated to the CTF IR event
 186         \p event.
 187
 188 This function returns a reference to the event class which was set to
 189 \p event in the first place with bt_ctf_event_set_packet().
 190
 191 @param[in] event        Event of which to get the associated packet.
 192 @returns                Packet associated to \p event,
 193                         or \c NULL if no packet is associated to
 194                         \p event or on error.
 195
 196 @prenotnull{event}
 197 @postrefcountsame{event}
 198 @postsuccessrefcountretinc
 199
 200 @sa bt_ctf_event_set_packet(): Associates a given event to a given
 201         packet.
 202 */
 203 extern struct bt_ctf_packet *bt_ctf_event_get_packet(
 204                 struct bt_ctf_event *event);
 205
 206 /**
 207 @brief  Associates the CTF IR event \p event to the CTF IR packet
 208         \p packet.
 209
 210 The \link ctfirstreamclass CTF IR stream class\endlink of the
 211 parent \link ctfirstream CTF IR stream\endlink of \p packet \em must
 212 be the same as the parent stream class of the
 213 \link ctfireventclass CTF IR event class\endlink returned
 214 by bt_ctf_event_get_class() for \p event.
 215
 216 You \em must call this function to create an event-packet association
 217 before you call bt_notification_event_create() with \p event.
 218
 219 On success, this function also sets the parent stream object of
 220 \p event to the parent stream of \p packet.
 221
 222 @param[in] event        Event to which to associate \p packet.
 223 @param[in] packet       Packet to associate to \p event.
 224 @returns                0 on success, or a negative value on error.
 225
 226 @prenotnull{event}
 227 @prenotnull{packet}
 228 @prehot{event}
 229 @pre The parent stream class of \p packet is the same as the parent
 230         stream class of \p event.
 231 @postsuccessrefcountretinc
 232
 233 @sa bt_ctf_event_get_packet(): Returns the associated packet of a
 234         given event object.
 235 */
 236 extern int bt_ctf_event_set_packet(struct bt_ctf_event *event,
 237                 struct bt_ctf_packet *packet);
 238
 239 /**
 240 @brief  Returns the parent CTF IR stream associated to the CTF IR event
 241         \p event.
 242
 243 @param[in] event        Event of which to get the parent stream.
 244 @returns                Parent stream of \p event, or \c NULL on error.
 245
 246 @prenotnull{event}
 247 @postrefcountsame{event}
 248 @postsuccessrefcountretinc
 249 */
 250 extern struct bt_ctf_stream *bt_ctf_event_get_stream(
 251                 struct bt_ctf_event *event);
 252
 253 /** @} */
 254
 255 /**
 256 @name Contained fields functions
 257 @{
 258 */
 259
 260 /**
 261 @brief  Returns the stream event header field of the CTF IR event
 262         \p event.
 263
 264 @param[in] event        Event of which to get the stream event header
 265                         field.
 266 @returns                Stream event header field of \p event,
 267                         or \c NULL if the stream event header
 268                         field is not set or on error.
 269
 270 @prenotnull{event}
 271 @postrefcountsame{event}
 272 @postsuccessrefcountretinc
 273
 274 @sa bt_ctf_event_get_header(): Sets the stream event header
 275         field of a given event.
 276 */
 277 extern struct bt_ctf_field *bt_ctf_event_get_header(
 278                 struct bt_ctf_event *event);
 279
 280 /**
 281 @brief  Sets the stream event header field of the CTF IR event
 282         \p event to \p header.
 283
 284 The field type of \p header, as returned by bt_ctf_field_get_type(),
 285 \em must be equivalent to the field type returned by
 286 bt_ctf_stream_class_get_event_header_type() for the parent stream class
 287 of \p event.
 288
 289 @param[in] event        Event of which to set the stream event header
 290                         field.
 291 @param[in] header       Stream event header field.
 292 @returns                0 on success, or a negative value on error.
 293
 294 @prenotnull{event}
 295 @prenotnull{header}
 296 @prehot{event}
 297 @pre \p header has a field type equivalent to the field type returned by
 298         bt_ctf_stream_class_get_event_header_type() for the parent
 299         stream class of \p event.
 300 @postrefcountsame{event}
 301 @postsuccessrefcountinc{header}
 302
 303 @sa bt_ctf_event_get_header(): Returns the stream event header field
 304         of a given event.
 305 */
 306 extern int bt_ctf_event_set_header(struct bt_ctf_event *event,
 307                 struct bt_ctf_field *header);
 308
 309 /**
 310 @brief  Returns the stream event context field of the CTF IR event
 311         \p event.
 312
 313 @param[in] event        Event of which to get the stream event context
 314                         field.
 315 @returns                Stream event context field of \p event,
 316                         or \c NULL if the stream event context
 317                         field is not set or on error.
 318
 319 @prenotnull{event}
 320 @postrefcountsame{event}
 321 @postsuccessrefcountretinc
 322
 323 @sa bt_ctf_event_set_stream_event_context(): Sets the stream event
 324         context field of a given event.
 325 */
 326 extern struct bt_ctf_field *bt_ctf_event_get_stream_event_context(
 327                 struct bt_ctf_event *event);
 328
 329 /**
 330 @brief  Sets the stream event context field of the CTF IR event
 331         \p event to \p context.
 332
 333 The field type of \p context, as returned by bt_ctf_field_get_type(),
 334 \em must be equivalent to the field type returned by
 335 bt_ctf_stream_class_get_event_context_type() for the parent stream class
 336 of \p event.
 337
 338 @param[in] event        Event of which to set the stream event context
 339                         field.
 340 @param[in] context      Stream event context field.
 341 @returns                0 on success, or a negative value on error.
 342
 343 @prenotnull{event}
 344 @prenotnull{context}
 345 @prehot{event}
 346 @pre \p context has a field type equivalent to the field type returned
 347         by bt_ctf_stream_class_get_event_context_type() for the parent
 348         stream class of \p event.
 349 @postrefcountsame{event}
 350 @postsuccessrefcountinc{context}
 351
 352 @sa bt_ctf_event_get_stream_event_context(): Returns the stream event
 353         context field of a given event.
 354 */
 355 extern int bt_ctf_event_set_stream_event_context(struct bt_ctf_event *event,
 356                 struct bt_ctf_field *context);
 357
 358 /**
 359 @brief  Returns the event context field of the CTF IR event
 360         \p event.
 361
 362 @param[in] event        Event of which to get the event context
 363                         field.
 364 @returns                Event context field of \p event, or \c NULL if
 365                         the event context field is not set or on error.
 366
 367 @prenotnull{event}
 368 @postrefcountsame{event}
 369 @postsuccessrefcountretinc
 370
 371 @sa bt_ctf_event_set_event_context(): Sets the event context field of a
 372         given event.
 373 */
 374 extern struct bt_ctf_field *bt_ctf_event_get_event_context(
 375                 struct bt_ctf_event *event);
 376
 377 /**
 378 @brief  Sets the event context field of the CTF IR event
 379         \p event to \p context.
 380
 381 The field type of \p context, as returned by bt_ctf_field_get_type(),
 382 \em must be equivalent to the field type returned by
 383 bt_ctf_event_class_get_context_type() for the parent event class
 384 of \p event.
 385
 386 @param[in] event        Event of which to set the event context field.
 387 @param[in] context      Event context field.
 388 @returns                0 on success, or a negative value on error.
 389
 390 @prenotnull{event}
 391 @prenotnull{context}
 392 @prehot{event}
 393 @pre \p context has a field type equivalent to the field type returned
 394         by bt_ctf_event_class_get_context_type() for the parent
 395         event class of \p event.
 396 @postrefcountsame{event}
 397 @postsuccessrefcountinc{context}
 398
 399 @sa bt_ctf_event_get_event_context(): Returns the event context field of
 400         a given event.
 401 */
 402 extern int bt_ctf_event_set_event_context(struct bt_ctf_event *event,
 403                 struct bt_ctf_field *context);
 404
 405 /**
 406 @brief  Returns the event payload field of the CTF IR event
 407         \p event.
 408
 409 @param[in] event        Event of which to get the event payload
 410                         field.
 411 @returns                Event payload field of \p event, or \c NULL if
 412                         the event payload field is not set or on error.
 413
 414 @prenotnull{event}
 415 @postrefcountsame{event}
 416 @postsuccessrefcountretinc
 417
 418 @sa bt_ctf_event_set_payload_field(): Sets the event payload field of a
 419         given event.
 420 */
 421 extern struct bt_ctf_field *bt_ctf_event_get_payload_field(
 422                 struct bt_ctf_event *event);
 423
 424 /**
 425 @brief  Sets the event payload field of the CTF IR event
 426         \p event to \p payload.
 427
 428 The field type of \p payload, as returned by bt_ctf_field_get_type(),
 429 \em must be equivalent to the field type returned by
 430 bt_ctf_event_class_get_payload_type() for the parent event class
 431 of \p event.
 432
 433 @param[in] event        Event of which to set the event payload field.
 434 @param[in] payload      Event payload field.
 435 @returns                0 on success, or a negative value on error.
 436
 437 @prenotnull{event}
 438 @prenotnull{payload}
 439 @prehot{event}
 440 @pre \p payload has a field type equivalent to the field type returned
 441         by bt_ctf_event_class_get_payload_type() for the parent
 442         event class of \p event.
 443 @postrefcountsame{event}
 444 @postsuccessrefcountinc{payload}
 445
 446 @sa bt_ctf_event_get_payload_field(): Returns the event payload field of
 447         a given event.
 448 */
 449 extern int bt_ctf_event_set_payload_field(struct bt_ctf_event *event,
 450                 struct bt_ctf_field *payload);
 451
 452 /** @cond DOCUMENT */
 453
 454 /*
 455  * TODO: Doxygenize.
 456  *
 457  * bt_ctf_event_get_payload: get an event's field.
 458  *
 459  * Returns the field matching "name". bt_put() must be called on the
 460  * returned value.
 461  *
 462  * @param event Event instance.
 463  * @param name Event field name, see notes.
 464  *
 465  * Returns a field instance on success, NULL on error.
 466  *
 467  * Note: Passing a name will cause the function to perform a look-up by
 468  *      name assuming the event's payload is a structure. This will return
 469  *      the raw payload instance if name is NULL.
 470  */
 471 extern struct bt_ctf_field *bt_ctf_event_get_payload(struct bt_ctf_event *event,
 472                 const char *name);
 473
 474 /*
 475  * TODO: Doxygenize.
 476  *
 477  * bt_ctf_event_get_payload_by_index: Get event's field by index.
 478  *
 479  * Returns the field associated with the provided index. bt_put()
 480  * must be called on the returned value. The indexes to be provided are
 481  * the same as can be retrieved from the event class.
 482  *
 483  * @param event Event.
 484  * @param index Index of field.
 485  *
 486  * Returns the event's field, NULL on error.
 487  *
 488  * Note: Will return an error if the payload's type is not a structure.
 489  */
 490 extern struct bt_ctf_field *bt_ctf_event_get_payload_by_index(
 491                 struct bt_ctf_event *event, int index);
 492
 493 /*
 494  * TODO: Doxygenize.
 495  *
 496  * bt_ctf_event_set_payload: set an event's field.
 497  *
 498  * Set a manually allocated field as an event's payload. The event will share
 499  * the field's ownership by using its reference count.
 500  * bt_put() must be called on the returned value.
 501  *
 502  * @param event Event instance.
 503  * @param name Event field name, see notes.
 504  * @param value Instance of a field whose type corresponds to the event's field.
 505  *
 506  * Returns 0 on success, a negative value on error.
 507  *
 508  * Note: The function will return an error if a name is provided and the payload
 509  *      type is not a structure. If name is NULL, the payload field will be set
 510  *      directly and must match the event class' payload's type.
 511  */
 512 extern int bt_ctf_event_set_payload(struct bt_ctf_event *event,
 513                 const char *name,
 514                 struct bt_ctf_field *value);
 515
 516 /** @endcond */
 517
 518 /** @} */
 519
 520 /**
 521 @name Clock value functions
 522 @{
 523 */
 524
 525 /**
 526 @brief  Returns the value, as of the CTF IR event \p event, of the
 527         clock described by the
 528         \link ctfirclockclass CTF IR clock class\endlink \p clock_class.
 529
 530 @param[in] event        Event of which to get the value of the clock
 531                         described by \p clock_class.
 532 @param[in] clock_class  Class of the clock of which to get the value.
 533 @returns                Value of the clock described by \p clock_class
 534                         as of \p event.
 535
 536 @prenotnull{event}
 537 @prenotnull{clock_class}
 538 @postrefcountsame{event}
 539 @postrefcountsame{clock_class}
 540 @postsuccessrefcountretinc
 541
 542 @sa bt_ctf_event_set_clock_value(): Sets the clock value of a given event.
 543 */
 544 extern struct bt_ctf_clock_value *bt_ctf_event_get_clock_value(
 545                 struct bt_ctf_event *event, struct bt_ctf_clock *clock_class);
 546
 547 /**
 548 @brief  Sets the value, as of the CTF IR event \p event, of the
 549         clock described by the
 550         \link ctfirclockclass CTF IR clock class\endlink \p clock_class.
 551
 552 @param[in] event        Event of which to set the value of the clock
 553                         described by \p clock_class.
 554 @param[in] clock_class  Class of the clock of which to set the value
 555                         for \p event.
 556 @param[in] clock_value  Value of the clock described by \p clock_class
 557                         as of \p event.
 558 @returns                0 on success, or a negative value on error.
 559
 560 @prenotnull{event}
 561 @prenotnull{clock_class}
 562 @prenotnull{clock_value}
 563 @prehot{event}
 564 @postrefcountsame{event}
 565 @postrefcountsame{clock_class}
 566
 567 @sa bt_ctf_event_get_clock_value(): Returns the clock value of
 568         a given event.
 569 */
 570 extern int bt_ctf_event_set_clock_value(
 571                 struct bt_ctf_event *event, struct bt_ctf_clock *clock_class,
 572                 struct bt_ctf_clock_value *clock_value);
 573
 574 /** @} */
 575
 576 /** @} */
 577
 578 #ifdef __cplusplus
 579 }
 580 #endif
 581
 582 #endif /* BABELTRACE_CTF_IR_EVENT_H */