| 1 | #ifndef BABELTRACE2_TRACE_IR_PACKET_H |
| 2 | #define BABELTRACE2_TRACE_IR_PACKET_H |
| 3 | |
| 4 | /* |
| 5 | * Copyright (c) 2010-2019 EfficiOS Inc. and Linux Foundation |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 8 | * of this software and associated documentation files (the "Software"), to deal |
| 9 | * in the Software without restriction, including without limitation the rights |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 11 | * copies of the Software, and to permit persons to whom the Software is |
| 12 | * furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 20 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 23 | * SOFTWARE. |
| 24 | */ |
| 25 | |
| 26 | #ifndef __BT_IN_BABELTRACE_H |
| 27 | # error "Please include <babeltrace2/babeltrace.h> instead." |
| 28 | #endif |
| 29 | |
| 30 | #include <stdint.h> |
| 31 | |
| 32 | #include <babeltrace2/types.h> |
| 33 | |
| 34 | #ifdef __cplusplus |
| 35 | extern "C" { |
| 36 | #endif |
| 37 | |
| 38 | /*! |
| 39 | @defgroup api-tir-pkt Packet |
| 40 | @ingroup api-tir |
| 41 | |
| 42 | @brief |
| 43 | Trace packet. |
| 44 | |
| 45 | A <strong><em>packet</em></strong> is a conceptual container of |
| 46 | \bt_p_ev within a \bt_stream. |
| 47 | |
| 48 | Some trace formats group events together within packets. This is the |
| 49 | case, for example, of the |
| 50 | <a href="https://diamon.org/ctf/">Common Trace Format</a>. |
| 51 | |
| 52 | Because a packet could contain millions of events, there are no actual |
| 53 | links from a packet to its events. However, there are links from a |
| 54 | packet's events to it (see bt_event_borrow_packet() and |
| 55 | bt_event_borrow_packet_const()). |
| 56 | |
| 57 | A packet can contain a context \bt_field which is data associated to |
| 58 | all the events of the packet. |
| 59 | |
| 60 | A packet is a \ref api-tir "trace IR" data object. |
| 61 | |
| 62 | A packet conceptually belongs to a \bt_stream. Borrow the stream of a |
| 63 | packet with bt_packet_borrow_stream() and |
| 64 | bt_packet_borrow_stream_const(). |
| 65 | |
| 66 | Before you create a packet for a given stream, the stream's class must |
| 67 | \ref api-tir-stream-cls-prop-supports-pkt "support packets". |
| 68 | |
| 69 | Create a packet with bt_packet_create(). You can then use this packet to |
| 70 | create a \bt_pb_msg and a \bt_pe_msg. |
| 71 | |
| 72 | A packet is a \ref api-fund-shared-object "shared object": get a |
| 73 | new reference with bt_packet_get_ref() and put an existing |
| 74 | reference with bt_packet_put_ref(). |
| 75 | |
| 76 | Some library functions \ref api-fund-freezing "freeze" packets on |
| 77 | success. The documentation of those functions indicate this |
| 78 | postcondition. |
| 79 | |
| 80 | The type of a packet is #bt_packet. |
| 81 | |
| 82 | <h1>Property</h1> |
| 83 | |
| 84 | A packet has the following property: |
| 85 | |
| 86 | <dl> |
| 87 | <dt>\anchor api-tir-pkt-prop-ctx Context field</dt> |
| 88 | <dd> |
| 89 | Packet's context \bt_field. |
| 90 | |
| 91 | The context of a packet contains data associated to all its |
| 92 | events. |
| 93 | |
| 94 | The \ref api-tir-fc "class" of a packet's context field is set |
| 95 | at the packet's \bt_stream_cls level. See |
| 96 | bt_stream_class_set_packet_context_field_class() |
| 97 | bt_stream_class_borrow_packet_context_field_class(), |
| 98 | and bt_stream_class_borrow_packet_context_field_class_const() |
| 99 | |
| 100 | Use bt_packet_borrow_context_field() and |
| 101 | bt_packet_borrow_context_field_const(). |
| 102 | </dd> |
| 103 | </dl> |
| 104 | */ |
| 105 | |
| 106 | /*! @{ */ |
| 107 | |
| 108 | /*! |
| 109 | @name Type |
| 110 | @{ |
| 111 | |
| 112 | @typedef struct bt_packet bt_packet; |
| 113 | |
| 114 | @brief |
| 115 | Packet. |
| 116 | |
| 117 | @} |
| 118 | */ |
| 119 | |
| 120 | /*! |
| 121 | @name Creation |
| 122 | @{ |
| 123 | */ |
| 124 | |
| 125 | /*! |
| 126 | @brief |
| 127 | Creates a packet for the \bt_stream \bt_p{stream}. |
| 128 | |
| 129 | @attention |
| 130 | @parblock |
| 131 | Only use this function if |
| 132 | |
| 133 | @code |
| 134 | bt_stream_class_supports_packets(bt_stream_borrow_class_const(stream)) |
| 135 | @endcode |
| 136 | |
| 137 | returns #BT_TRUE. |
| 138 | @endparblock |
| 139 | |
| 140 | On success, the returned packet has the following property value: |
| 141 | |
| 142 | <table> |
| 143 | <tr> |
| 144 | <th>Property |
| 145 | <th>Value |
| 146 | <tr> |
| 147 | <td>\ref api-tir-pkt-prop-ctx "Context field" |
| 148 | <td> |
| 149 | Unset instance of the |
| 150 | \ref api-tir-stream-cls-prop-pc-fc "packet context field class" of |
| 151 | the \ref api-tir-stream-cls "class" of \bt_p{stream}. |
| 152 | </table> |
| 153 | |
| 154 | @param[in] stream |
| 155 | Stream for which to create the packet. |
| 156 | |
| 157 | @returns |
| 158 | New packet reference, or \c NULL on memory error. |
| 159 | |
| 160 | @pre |
| 161 | <code>bt_stream_class_supports_packets(bt_stream_borrow_class_const(stream))</code> |
| 162 | returns #BT_TRUE. |
| 163 | */ |
| 164 | extern bt_packet *bt_packet_create(const bt_stream *stream); |
| 165 | |
| 166 | /*! @} */ |
| 167 | |
| 168 | /*! |
| 169 | @name Stream access |
| 170 | @{ |
| 171 | */ |
| 172 | |
| 173 | /*! |
| 174 | @brief |
| 175 | Borrows the \bt_stream conceptually containing the packet |
| 176 | \bt_p{packet}. |
| 177 | |
| 178 | @param[in] packet |
| 179 | Packet of which to borrow the stream conceptually containing it. |
| 180 | |
| 181 | @returns |
| 182 | \em Borrowed reference of the stream conceptually containing |
| 183 | \bt_p{packet}. |
| 184 | |
| 185 | @bt_pre_not_null{packet} |
| 186 | |
| 187 | @sa bt_packet_borrow_stream_const() — |
| 188 | \c const version of this function. |
| 189 | */ |
| 190 | extern bt_stream *bt_packet_borrow_stream(bt_packet *packet); |
| 191 | |
| 192 | /*! |
| 193 | @brief |
| 194 | Borrows the \bt_stream conceptually containing the packet |
| 195 | \bt_p{packet} (\c const version). |
| 196 | |
| 197 | See bt_packet_borrow_stream(). |
| 198 | */ |
| 199 | extern const bt_stream *bt_packet_borrow_stream_const( |
| 200 | const bt_packet *packet); |
| 201 | |
| 202 | /*! @} */ |
| 203 | |
| 204 | /*! |
| 205 | @name Property |
| 206 | @{ |
| 207 | */ |
| 208 | |
| 209 | /*! |
| 210 | @brief |
| 211 | Borrows the context \bt_field of the packet \bt_p{packet}. |
| 212 | |
| 213 | See the \ref api-tir-pkt-prop-ctx "context field" property. |
| 214 | |
| 215 | @param[in] packet |
| 216 | Packet of which to borrow the context field. |
| 217 | |
| 218 | @returns |
| 219 | \em Borrowed reference of the context field of |
| 220 | \bt_p{packet}, or \c NULL if none. |
| 221 | |
| 222 | @bt_pre_not_null{packet} |
| 223 | |
| 224 | @sa bt_packet_borrow_context_field_const() — |
| 225 | \c const version of this function. |
| 226 | */ |
| 227 | extern |
| 228 | bt_field *bt_packet_borrow_context_field(bt_packet *packet); |
| 229 | |
| 230 | /*! |
| 231 | @brief |
| 232 | Borrows the context \bt_field of the packet \bt_p{packet} |
| 233 | (\c const version). |
| 234 | |
| 235 | See bt_packet_borrow_context_field(). |
| 236 | */ |
| 237 | extern |
| 238 | const bt_field *bt_packet_borrow_context_field_const( |
| 239 | const bt_packet *packet); |
| 240 | |
| 241 | /*! @} */ |
| 242 | |
| 243 | /*! |
| 244 | @name Reference count |
| 245 | @{ |
| 246 | */ |
| 247 | |
| 248 | /*! |
| 249 | @brief |
| 250 | Increments the \ref api-fund-shared-object "reference count" of |
| 251 | the packet \bt_p{packet}. |
| 252 | |
| 253 | @param[in] packet |
| 254 | @parblock |
| 255 | Packet of which to increment the reference count. |
| 256 | |
| 257 | Can be \c NULL. |
| 258 | @endparblock |
| 259 | |
| 260 | @sa bt_packet_put_ref() — |
| 261 | Decrements the reference count of a packet. |
| 262 | */ |
| 263 | extern void bt_packet_get_ref(const bt_packet *packet); |
| 264 | |
| 265 | /*! |
| 266 | @brief |
| 267 | Decrements the \ref api-fund-shared-object "reference count" of |
| 268 | the packet \bt_p{packet}. |
| 269 | |
| 270 | @param[in] packet |
| 271 | @parblock |
| 272 | Packet of which to decrement the reference count. |
| 273 | |
| 274 | Can be \c NULL. |
| 275 | @endparblock |
| 276 | |
| 277 | @sa bt_packet_get_ref() — |
| 278 | Increments the reference count of a packet. |
| 279 | */ |
| 280 | extern void bt_packet_put_ref(const bt_packet *packet); |
| 281 | |
| 282 | /*! |
| 283 | @brief |
| 284 | Decrements the reference count of the packet |
| 285 | \bt_p{_packet}, and then sets \bt_p{_packet} to \c NULL. |
| 286 | |
| 287 | @param _packet |
| 288 | @parblock |
| 289 | Packet of which to decrement the reference count. |
| 290 | |
| 291 | Can contain \c NULL. |
| 292 | @endparblock |
| 293 | |
| 294 | @bt_pre_assign_expr{_packet} |
| 295 | */ |
| 296 | #define BT_PACKET_PUT_REF_AND_RESET(_packet) \ |
| 297 | do { \ |
| 298 | bt_packet_put_ref(_packet); \ |
| 299 | (_packet) = NULL; \ |
| 300 | } while (0) |
| 301 | |
| 302 | /*! |
| 303 | @brief |
| 304 | Decrements the reference count of the packet \bt_p{_dst}, sets |
| 305 | \bt_p{_dst} to \bt_p{_src}, and then sets \bt_p{_src} to \c NULL. |
| 306 | |
| 307 | This macro effectively moves a packet reference from the expression |
| 308 | \bt_p{_src} to the expression \bt_p{_dst}, putting the existing |
| 309 | \bt_p{_dst} reference. |
| 310 | |
| 311 | @param _dst |
| 312 | @parblock |
| 313 | Destination expression. |
| 314 | |
| 315 | Can contain \c NULL. |
| 316 | @endparblock |
| 317 | @param _src |
| 318 | @parblock |
| 319 | Source expression. |
| 320 | |
| 321 | Can contain \c NULL. |
| 322 | @endparblock |
| 323 | |
| 324 | @bt_pre_assign_expr{_dst} |
| 325 | @bt_pre_assign_expr{_src} |
| 326 | */ |
| 327 | #define BT_PACKET_MOVE_REF(_dst, _src) \ |
| 328 | do { \ |
| 329 | bt_packet_put_ref(_dst); \ |
| 330 | (_dst) = (_src); \ |
| 331 | (_src) = NULL; \ |
| 332 | } while (0) |
| 333 | |
| 334 | /*! @} */ |
| 335 | |
| 336 | /*! @} */ |
| 337 | |
| 338 | #ifdef __cplusplus |
| 339 | } |
| 340 | #endif |
| 341 | |
| 342 | #endif /* BABELTRACE2_TRACE_IR_PACKET_H */ |