| 1 | /* |
| 2 | * SPDX-License-Identifier: MIT |
| 3 | * |
| 4 | * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com> |
| 5 | * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 6 | */ |
| 7 | |
| 8 | #ifndef BABELTRACE_LIB_TRACE_IR_EVENT_H |
| 9 | #define BABELTRACE_LIB_TRACE_IR_EVENT_H |
| 10 | |
| 11 | /* Protection: this file uses BT_LIB_LOG*() macros directly */ |
| 12 | #ifndef BT_LIB_LOG_SUPPORTED |
| 13 | # error Please include "lib/logging.h" before including this file. |
| 14 | #endif |
| 15 | |
| 16 | #include "lib/assert-cond.h" |
| 17 | #include <babeltrace2/value.h> |
| 18 | #include <babeltrace2/trace-ir/stream-class.h> |
| 19 | #include <babeltrace2/trace-ir/stream.h> |
| 20 | #include <babeltrace2/trace-ir/packet.h> |
| 21 | #include <babeltrace2/trace-ir/field.h> |
| 22 | #include "lib/object.h" |
| 23 | #include "common/assert.h" |
| 24 | #include <glib.h> |
| 25 | #include <stdbool.h> |
| 26 | |
| 27 | #include "event-class.h" |
| 28 | #include "field.h" |
| 29 | #include "packet.h" |
| 30 | #include "stream.h" |
| 31 | |
| 32 | #define BT_ASSERT_PRE_DEV_EVENT_HOT(_event) \ |
| 33 | BT_ASSERT_PRE_DEV_HOT(((const struct bt_event *) (_event)), \ |
| 34 | "Event", ": %!+e", (_event)) |
| 35 | |
| 36 | struct bt_event { |
| 37 | struct bt_object base; |
| 38 | |
| 39 | /* Owned by this */ |
| 40 | struct bt_event_class *class; |
| 41 | |
| 42 | /* Owned by this (can be `NULL`) */ |
| 43 | struct bt_packet *packet; |
| 44 | |
| 45 | /* Owned by this */ |
| 46 | struct bt_stream *stream; |
| 47 | |
| 48 | struct bt_field *common_context_field; |
| 49 | struct bt_field *specific_context_field; |
| 50 | struct bt_field *payload_field; |
| 51 | bool frozen; |
| 52 | }; |
| 53 | |
| 54 | void bt_event_destroy(struct bt_event *event); |
| 55 | |
| 56 | struct bt_event *bt_event_new(struct bt_event_class *event_class); |
| 57 | |
| 58 | void _bt_event_set_is_frozen(const struct bt_event *event, bool is_frozen); |
| 59 | |
| 60 | #ifdef BT_DEV_MODE |
| 61 | # define bt_event_set_is_frozen _bt_event_set_is_frozen |
| 62 | #else |
| 63 | # define bt_event_set_is_frozen(_event, _is_frozen) |
| 64 | #endif |
| 65 | |
| 66 | __attribute__((unused)) |
| 67 | static inline |
| 68 | void _bt_event_reset_dev_mode(struct bt_event *event) |
| 69 | { |
| 70 | BT_ASSERT_DBG(event); |
| 71 | |
| 72 | if (event->common_context_field) { |
| 73 | bt_field_set_is_frozen( |
| 74 | event->common_context_field, false); |
| 75 | bt_field_reset( |
| 76 | event->common_context_field); |
| 77 | } |
| 78 | |
| 79 | if (event->specific_context_field) { |
| 80 | bt_field_set_is_frozen( |
| 81 | event->specific_context_field, false); |
| 82 | bt_field_reset(event->specific_context_field); |
| 83 | } |
| 84 | |
| 85 | if (event->payload_field) { |
| 86 | bt_field_set_is_frozen( |
| 87 | event->payload_field, false); |
| 88 | bt_field_reset(event->payload_field); |
| 89 | } |
| 90 | } |
| 91 | |
| 92 | #ifdef BT_DEV_MODE |
| 93 | # define bt_event_reset_dev_mode _bt_event_reset_dev_mode |
| 94 | #else |
| 95 | # define bt_event_reset_dev_mode(_x) |
| 96 | #endif |
| 97 | |
| 98 | static inline |
| 99 | void bt_event_reset(struct bt_event *event) |
| 100 | { |
| 101 | BT_ASSERT_DBG(event); |
| 102 | BT_LIB_LOGD("Resetting event: %!+e", event); |
| 103 | bt_event_set_is_frozen(event, false); |
| 104 | bt_object_put_ref_no_null_check(&event->stream->base); |
| 105 | event->stream = NULL; |
| 106 | |
| 107 | if (event->packet) { |
| 108 | bt_object_put_ref_no_null_check(&event->packet->base); |
| 109 | event->packet = NULL; |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | static inline |
| 114 | void bt_event_recycle(struct bt_event *event) |
| 115 | { |
| 116 | struct bt_event_class *event_class; |
| 117 | |
| 118 | BT_ASSERT_DBG(event); |
| 119 | BT_LIB_LOGD("Recycling event: %!+e", event); |
| 120 | |
| 121 | /* |
| 122 | * Those are the important ordered steps: |
| 123 | * |
| 124 | * 1. Reset the event object (put any permanent reference it |
| 125 | * has, unfreeze it and its fields in developer mode, etc.), |
| 126 | * but do NOT put its class's reference. This event class |
| 127 | * contains the pool to which we're about to recycle this |
| 128 | * event object, so we must guarantee its existence thanks |
| 129 | * to this existing reference. |
| 130 | * |
| 131 | * 2. Move the event class reference to our `event_class` |
| 132 | * variable so that we can set the event's class member |
| 133 | * to NULL before recycling it. We CANNOT do this after |
| 134 | * we put the event class reference because this bt_object_put_ref() |
| 135 | * could destroy the event class, also destroying its |
| 136 | * event pool, thus also destroying our event object (this |
| 137 | * would result in an invalid write access). |
| 138 | * |
| 139 | * 3. Recycle the event object. |
| 140 | * |
| 141 | * 4. Put our event class reference. |
| 142 | */ |
| 143 | bt_event_reset(event); |
| 144 | event_class = event->class; |
| 145 | BT_ASSERT_DBG(event_class); |
| 146 | event->class = NULL; |
| 147 | bt_object_pool_recycle_object(&event_class->event_pool, event); |
| 148 | bt_object_put_ref_no_null_check(&event_class->base); |
| 149 | } |
| 150 | |
| 151 | #endif /* BABELTRACE_LIB_TRACE_IR_EVENT_H */ |