mirror of
https://github.com/klzgrad/naiveproxy.git
synced 2024-11-28 08:16:09 +03:00
110 lines
3.7 KiB
C++
110 lines
3.7 KiB
C++
// Copyright 2016 The Chromium Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#ifndef BASE_TRACE_EVENT_TRACE_CATEGORY_H_
|
|
#define BASE_TRACE_EVENT_TRACE_CATEGORY_H_
|
|
|
|
#include <stdint.h>
|
|
|
|
namespace base {
|
|
namespace trace_event {
|
|
|
|
// Captures the state of an invidivual trace category. Nothing except tracing
|
|
// internals (e.g., TraceLog) is supposed to have non-const Category pointers.
|
|
struct TraceCategory {
|
|
// The TRACE_EVENT macros should only use this value as a bool.
|
|
// These enum values are effectively a public API and third_party projects
|
|
// depend on their value. Hence, never remove or recycle existing bits, unless
|
|
// you are sure that all the third-party projects that depend on this have
|
|
// been updated.
|
|
enum StateFlags : uint8_t {
|
|
ENABLED_FOR_RECORDING = 1 << 0,
|
|
|
|
// Not used anymore.
|
|
DEPRECATED_ENABLED_FOR_MONITORING = 1 << 1,
|
|
DEPRECATED_ENABLED_FOR_EVENT_CALLBACK = 1 << 2,
|
|
|
|
ENABLED_FOR_ETW_EXPORT = 1 << 3,
|
|
ENABLED_FOR_FILTERING = 1 << 4
|
|
};
|
|
|
|
static const TraceCategory* FromStatePtr(const uint8_t* state_ptr) {
|
|
static_assert(
|
|
offsetof(TraceCategory, state_) == 0,
|
|
"|state_| must be the first field of the TraceCategory class.");
|
|
return reinterpret_cast<const TraceCategory*>(state_ptr);
|
|
}
|
|
|
|
bool is_valid() const { return name_ != nullptr; }
|
|
void set_name(const char* name) { name_ = name; }
|
|
const char* name() const {
|
|
DCHECK(is_valid());
|
|
return name_;
|
|
}
|
|
|
|
// TODO(primiano): This is an intermediate solution to deal with the fact that
|
|
// today TRACE_EVENT* macros cache the state ptr. They should just cache the
|
|
// full TraceCategory ptr, which is immutable, and use these helper function
|
|
// here. This will get rid of the need of this awkward ptr getter completely.
|
|
const uint8_t* state_ptr() const {
|
|
return const_cast<const uint8_t*>(&state_);
|
|
}
|
|
|
|
uint8_t state() const {
|
|
return *const_cast<volatile const uint8_t*>(&state_);
|
|
}
|
|
|
|
bool is_enabled() const { return state() != 0; }
|
|
|
|
void set_state(uint8_t state) {
|
|
*const_cast<volatile uint8_t*>(&state_) = state;
|
|
}
|
|
|
|
void clear_state_flag(StateFlags flag) { set_state(state() & (~flag)); }
|
|
void set_state_flag(StateFlags flag) { set_state(state() | flag); }
|
|
|
|
uint32_t enabled_filters() const {
|
|
return *const_cast<volatile const uint32_t*>(&enabled_filters_);
|
|
}
|
|
|
|
bool is_filter_enabled(size_t index) const {
|
|
DCHECK(index < sizeof(enabled_filters_) * 8);
|
|
return (enabled_filters() & (1 << index)) != 0;
|
|
}
|
|
|
|
void set_enabled_filters(uint32_t enabled_filters) {
|
|
*const_cast<volatile uint32_t*>(&enabled_filters_) = enabled_filters;
|
|
}
|
|
|
|
void reset_for_testing() {
|
|
set_state(0);
|
|
set_enabled_filters(0);
|
|
}
|
|
|
|
// These fields should not be accessed directly, not even by tracing code.
|
|
// The only reason why these are not private is because it makes it impossible
|
|
// to have a global array of TraceCategory in category_registry.cc without
|
|
// creating initializers. See discussion on goo.gl/qhZN94 and
|
|
// crbug.com/{660967,660828}.
|
|
|
|
// The enabled state. TRACE_EVENT* macros will capture events if any of the
|
|
// flags here are set. Since TRACE_EVENTx macros are used in a lot of
|
|
// fast-paths, accesses to this field are non-barriered and racy by design.
|
|
// This field is mutated when starting/stopping tracing and we don't care
|
|
// about missing some events.
|
|
uint8_t state_;
|
|
|
|
// When ENABLED_FOR_FILTERING is set, this contains a bitmap to the
|
|
// corresponding filter (see event_filters.h).
|
|
uint32_t enabled_filters_;
|
|
|
|
// TraceCategory group names are long lived static strings.
|
|
const char* name_;
|
|
};
|
|
|
|
} // namespace trace_event
|
|
} // namespace base
|
|
|
|
#endif // BASE_TRACE_EVENT_TRACE_CATEGORY_H_
|