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