src/lib/trace-ir/event.h

   1 #ifndef BABELTRACE_TRACE_IR_EVENT_INTERNAL_H
   2 #define BABELTRACE_TRACE_IR_EVENT_INTERNAL_H
   3
   4 /*
   5  * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
   6  * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a copy
   9  * of this software and associated documentation files (the "Software"), to deal
  10  * in the Software without restriction, including without limitation the rights
  11  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  12  * copies of the Software, and to permit persons to whom the Software is
  13  * furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  21  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  23  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  24  * SOFTWARE.
  25  */
  26
  27 /* Protection: this file uses BT_LIB_LOG*() macros directly */
  28 #ifndef BT_LIB_LOG_SUPPORTED
  29 # error Please include "lib/logging.h" before including this file.
  30 #endif
  31
  32 #include "lib/assert-pre.h"
  33 #include "common/macros.h"
  34 #include <babeltrace2/value.h>
  35 #include <babeltrace2/trace-ir/stream-class.h>
  36 #include <babeltrace2/trace-ir/stream.h>
  37 #include <babeltrace2/trace-ir/packet.h>
  38 #include <babeltrace2/trace-ir/field.h>
  39 #include "lib/object.h"
  40 #include "common/assert.h"
  41 #include <glib.h>
  42 #include <stdbool.h>
  43
  44 #include "event-class.h"
  45 #include "field.h"
  46 #include "field-wrapper.h"
  47 #include "packet.h"
  48 #include "stream.h"
  49
  50 #define BT_ASSERT_PRE_DEV_EVENT_HOT(_event)                             \
  51         BT_ASSERT_PRE_DEV_HOT(((const struct bt_event *) (_event)),     \
  52                 "Event", ": %!+e", (_event))
  53
  54 struct bt_event {
  55         struct bt_object base;
  56
  57         /* Owned by this */
  58         struct bt_event_class *class;
  59
  60         /* Owned by this (can be `NULL`) */
  61         struct bt_packet *packet;
  62
  63         /* Owned by this */
  64         struct bt_stream *stream;
  65
  66         struct bt_field *common_context_field;
  67         struct bt_field *specific_context_field;
  68         struct bt_field *payload_field;
  69         bool frozen;
  70 };
  71
  72 BT_HIDDEN
  73 void bt_event_destroy(struct bt_event *event);
  74
  75 BT_HIDDEN
  76 struct bt_event *bt_event_new(struct bt_event_class *event_class);
  77
  78 BT_HIDDEN
  79 void _bt_event_set_is_frozen(const struct bt_event *event, bool is_frozen);
  80
  81 #ifdef BT_DEV_MODE
  82 # define bt_event_set_is_frozen         _bt_event_set_is_frozen
  83 #else
  84 # define bt_event_set_is_frozen(_event, _is_frozen)
  85 #endif
  86
  87 __attribute__((unused))
  88 static inline
  89 void _bt_event_reset_dev_mode(struct bt_event *event)
  90 {
  91         BT_ASSERT_DBG(event);
  92
  93         if (event->common_context_field) {
  94                 bt_field_set_is_frozen(
  95                         event->common_context_field, false);
  96                 bt_field_reset(
  97                         event->common_context_field);
  98         }
  99
 100         if (event->specific_context_field) {
 101                 bt_field_set_is_frozen(
 102                         event->specific_context_field, false);
 103                 bt_field_reset(event->specific_context_field);
 104         }
 105
 106         if (event->payload_field) {
 107                 bt_field_set_is_frozen(
 108                         event->payload_field, false);
 109                 bt_field_reset(event->payload_field);
 110         }
 111 }
 112
 113 #ifdef BT_DEV_MODE
 114 # define bt_event_reset_dev_mode        _bt_event_reset_dev_mode
 115 #else
 116 # define bt_event_reset_dev_mode(_x)
 117 #endif
 118
 119 static inline
 120 void bt_event_reset(struct bt_event *event)
 121 {
 122         BT_ASSERT_DBG(event);
 123         BT_LIB_LOGD("Resetting event: %!+e", event);
 124         bt_event_set_is_frozen(event, false);
 125         bt_object_put_ref_no_null_check(&event->stream->base);
 126         event->stream = NULL;
 127
 128         if (event->packet) {
 129                 bt_object_put_ref_no_null_check(&event->packet->base);
 130                 event->packet = NULL;
 131         }
 132 }
 133
 134 static inline
 135 void bt_event_recycle(struct bt_event *event)
 136 {
 137         struct bt_event_class *event_class;
 138
 139         BT_ASSERT_DBG(event);
 140         BT_LIB_LOGD("Recycling event: %!+e", event);
 141
 142         /*
 143          * Those are the important ordered steps:
 144          *
 145          * 1. Reset the event object (put any permanent reference it
 146          *    has, unfreeze it and its fields in developer mode, etc.),
 147          *    but do NOT put its class's reference. This event class
 148          *    contains the pool to which we're about to recycle this
 149          *    event object, so we must guarantee its existence thanks
 150          *    to this existing reference.
 151          *
 152          * 2. Move the event class reference to our `event_class`
 153          *    variable so that we can set the event's class member
 154          *    to NULL before recycling it. We CANNOT do this after
 155          *    we put the event class reference because this bt_object_put_ref()
 156          *    could destroy the event class, also destroying its
 157          *    event pool, thus also destroying our event object (this
 158          *    would result in an invalid write access).
 159          *
 160          * 3. Recycle the event object.
 161          *
 162          * 4. Put our event class reference.
 163          */
 164         bt_event_reset(event);
 165         event_class = event->class;
 166         BT_ASSERT_DBG(event_class);
 167         event->class = NULL;
 168         bt_object_pool_recycle_object(&event_class->event_pool, event);
 169         bt_object_put_ref_no_null_check(&event_class->base);
 170 }
 171
 172 static inline
 173 void bt_event_set_packet(struct bt_event *event, struct bt_packet *packet)
 174 {
 175         BT_ASSERT_PRE_DEV_NON_NULL(event, "Event");
 176         BT_ASSERT_PRE_DEV_NON_NULL(packet, "Packet");
 177         BT_ASSERT_PRE_DEV_EVENT_HOT(event);
 178         BT_ASSERT_PRE_DEV(bt_event_class_borrow_stream_class(
 179                 event->class) == packet->stream->class,
 180                 "Packet's stream class and event's stream class differ: "
 181                 "%![event-]+e, %![packet-]+a", event, packet);
 182         BT_ASSERT_DBG(event->stream->class->supports_packets);
 183         BT_ASSERT_DBG(!event->packet);
 184         event->packet = packet;
 185         bt_object_get_ref_no_null_check_no_parent_check(&event->packet->base);
 186         BT_LIB_LOGD("Set event's packet: %![event-]+e, %![packet-]+a",
 187                 event, packet);
 188 }
 189
 190 static inline
 191 void bt_event_set_stream(struct bt_event *event, struct bt_stream *stream)
 192 {
 193         BT_ASSERT_PRE_DEV_NON_NULL(event, "Event");
 194         BT_ASSERT_PRE_DEV_NON_NULL(stream, "Stream");
 195         BT_ASSERT_PRE_DEV_EVENT_HOT(event);
 196         BT_ASSERT_PRE_DEV(bt_event_class_borrow_stream_class(
 197                 event->class) == stream->class,
 198                 "Stream's class and event's stream class differ: "
 199                 "%![event-]+e, %![stream-]+s", event, stream);
 200         BT_ASSERT_DBG(!event->stream);
 201         event->stream = stream;
 202         bt_object_get_ref_no_null_check_no_parent_check(&event->stream->base);
 203         BT_LIB_LOGD("Set event's stream: %![event-]+e, %![stream-]+s",
 204                 event, stream);
 205 }
 206
 207 static inline
 208 struct bt_event *bt_event_create(struct bt_event_class *event_class,
 209                 struct bt_packet *packet, struct bt_stream *stream)
 210 {
 211         struct bt_event *event = NULL;
 212
 213         BT_ASSERT_DBG(event_class);
 214         BT_ASSERT_DBG(stream);
 215         event = bt_object_pool_create_object(&event_class->event_pool);
 216         if (G_UNLIKELY(!event)) {
 217                 BT_LIB_LOGE_APPEND_CAUSE(
 218                         "Cannot allocate one event from event class's event pool: "
 219                         "%![ec-]+E", event_class);
 220                 goto end;
 221         }
 222
 223         if (G_LIKELY(!event->class)) {
 224                 event->class = event_class;
 225                 bt_object_get_ref_no_null_check(&event_class->base);
 226         }
 227
 228         bt_event_set_stream(event, stream);
 229
 230         if (packet) {
 231                 BT_ASSERT_DBG(packet);
 232                 bt_event_set_packet(event, packet);
 233         }
 234
 235         goto end;
 236
 237 end:
 238         return event;
 239 }
 240
 241 #endif /* BABELTRACE_TRACE_IR_EVENT_INTERNAL_H */