include/babeltrace/ctf-ir/packet.h

   1 #ifndef BABELTRACE_CTF_IR_PACKET_H
   2 #define BABELTRACE_CTF_IR_PACKET_H
   3
   4 /*
   5  * BabelTrace - CTF IR: Stream packet
   6  *
   7  * Copyright 2016 Philippe Proulx <pproulx@efficios.com>
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a copy
  10  * of this software and associated documentation files (the "Software"), to deal
  11  * in the Software without restriction, including without limitation the rights
  12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13  * copies of the Software, and to permit persons to whom the Software is
  14  * furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included in
  17  * all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  25  * SOFTWARE.
  26  *
  27  * The Common Trace Format (CTF) Specification is available at
  28  * http://www.efficios.com/ctf
  29  */
  30
  31 #include <stdint.h>
  32
  33 /* For bt_get() */
  34 #include <babeltrace/ref.h>
  35
  36 /* For bt_bool */
  37 #include <babeltrace/types.h>
  38
  39 #ifdef __cplusplus
  40 extern "C" {
  41 #endif
  42
  43 /**
  44 @defgroup ctfirpacket CTF IR packet
  45 @ingroup ctfir
  46 @brief CTF IR packet.
  47
  48 @code
  49 #include <babeltrace/ctf-ir/packet.h>
  50 @endcode
  51
  52 A CTF IR <strong><em>packet</em></strong> is a container of packet
  53 fields, that is, of the <strong>trace packet header</strong> and
  54 <strong>stream packet context</strong> fields.
  55
  56 As a reminder, here's the structure of a CTF packet:
  57
  58 @imgpacketstructure
  59
  60 You can create a CTF IR packet \em from a
  61 \link ctfirstream CTF IR stream\endlink with bt_packet_create(). The
  62 stream you use to create a packet object becomes its parent.
  63
  64 When you set the trace packet header and stream packet context fields of
  65 a packet with resp. bt_packet_set_header() and
  66 bt_packet_set_context(), their field type \em must be equivalent to
  67 the field types returned by resp. bt_trace_get_packet_header_type()
  68 and bt_stream_class_get_packet_context_type() for its parent trace
  69 class and stream class.
  70
  71 You can attach a packet object to a \link ctfirevent CTF IR
  72 event\endlink object with bt_event_set_packet().
  73
  74 As with any Babeltrace object, CTF IR packet objects have
  75 <a href="https://en.wikipedia.org/wiki/Reference_counting">reference
  76 counts</a>. See \ref refs to learn more about the reference counting
  77 management of Babeltrace objects.
  78
  79 bt_notification_event_create() \em freezes its event parameter on
  80 success, which in turns freezes the event's associated packet object.
  81 This is the only way that a CTF IR packet object can be frozen.
  82 You cannot modify a frozen packet: it is considered immutable,
  83 except for \link refs reference counting\endlink.
  84
  85 @sa ctfirstream
  86 @sa ctfirstreamclass
  87 @sa ctfirtraceclass
  88
  89 @file
  90 @brief CTF IR packet type and functions.
  91 @sa ctfirpacket
  92
  93 @addtogroup ctfirpacket
  94 @{
  95 */
  96
  97 /**
  98 @struct bt_packet
  99 @brief A CTF IR packet.
 100 @sa ctfirpacket
 101 */
 102 struct bt_packet;
 103 struct bt_packet_header_field;
 104 struct bt_packet_context_field;
 105 struct bt_stream;
 106 struct bt_clock_value;
 107 struct bt_clock_class;
 108
 109 /**
 110 @name Creation and parent access functions
 111 @{
 112 */
 113
 114 /**
 115 @brief  Creates a default CTF IR packet with \p stream as its parent
 116         CTF IR stream.
 117
 118 On success, the packet object's trace packet header and stream packet
 119 context fields are not set. You can set them with resp.
 120 bt_packet_set_header() and bt_packet_set_context().
 121
 122 @param[in] stream       Parent CTF IR stream of the packet to create.
 123 @returns                Created packet, or \c NULL on error.
 124
 125 @prenotnull{stream}
 126 @postsuccessrefcountret1
 127 */
 128 extern struct bt_packet *bt_packet_create(struct bt_stream *stream);
 129
 130 extern struct bt_stream *bt_packet_borrow_stream(struct bt_packet *packet);
 131
 132 /**
 133 @brief  Returns the parent CTF IR stream of the CTF IR packet \p packet.
 134
 135 This function returns a reference to the stream which was used to create
 136 the packet object in the first place with bt_packet_create().
 137
 138 @param[in] packet       Packet of which to get the parent stream.
 139 @returns                Parent stream of \p packet, or \c NULL on error.
 140
 141 @prenotnull{packet}
 142 @postrefcountsame{packet}
 143 @postsuccessrefcountretinc
 144 */
 145 static inline
 146 struct bt_stream *bt_packet_get_stream(
 147                 struct bt_packet *packet)
 148 {
 149         return bt_get(bt_packet_borrow_stream(packet));
 150 }
 151
 152 /** @} */
 153
 154 /**
 155 @name Contained fields functions
 156 @{
 157 */
 158
 159 extern
 160 struct bt_field *bt_packet_borrow_header(struct bt_packet *packet);
 161
 162 extern
 163 int bt_packet_move_header(struct bt_packet *packet,
 164                 struct bt_packet_header_field *header);
 165
 166 extern
 167 struct bt_field *bt_packet_borrow_context(struct bt_packet *packet);
 168
 169 extern
 170 int bt_packet_move_context(struct bt_packet *packet,
 171                 struct bt_packet_context_field *context);
 172
 173 /** @} */
 174
 175 extern int bt_packet_set_beginning_clock_value(struct bt_packet *packet,
 176                 struct bt_clock_class *clock_class, uint64_t raw_value,
 177                 bt_bool is_default);
 178
 179 extern struct bt_clock_value *bt_packet_borrow_default_beginning_clock_value(
 180                 struct bt_packet *packet);
 181
 182 extern int bt_packet_set_end_clock_value(struct bt_packet *packet,
 183                 struct bt_clock_class *clock_class, uint64_t raw_value,
 184                 bt_bool is_default);
 185
 186 extern struct bt_clock_value *bt_packet_borrow_default_end_clock_value(
 187                 struct bt_packet *packet);
 188
 189 /** @} */
 190
 191 #ifdef __cplusplus
 192 }
 193 #endif
 194
 195 #endif /* BABELTRACE_CTF_IR_PACKET_H */