Nagram/TMessagesProj/jni/libtgvoip3/webrtc_dsp/rtc_base/trace_event.h

// Copyright (c) 2012 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 under third_party_mods/chromium or at:
// http://src.chromium.org/svn/trunk/src/LICENSE

#ifndef RTC_BASE_TRACE_EVENT_H_
#define RTC_BASE_TRACE_EVENT_H_

#include <string>

#include "rtc_base/event_tracer.h"

#if defined(TRACE_EVENT0)
#error "Another copy of trace_event.h has already been included."
#endif

// Extracted from Chromium's src/base/debug/trace_event.h.

// This header is designed to give you trace_event macros without specifying
// how the events actually get collected and stored. If you need to expose trace
// event to some other universe, you can copy-and-paste this file,
// implement the TRACE_EVENT_API macros, and do any other necessary fixup for
// the target platform. The end result is that multiple libraries can funnel
// events through to a shared trace event collector.

// Trace events are for tracking application performance and resource usage.
// Macros are provided to track:
//    Begin and end of function calls
//    Counters
//
// Events are issued against categories. Whereas RTC_LOG's
// categories are statically defined, TRACE categories are created
// implicitly with a string. For example:
//   TRACE_EVENT_INSTANT0("MY_SUBSYSTEM", "SomeImportantEvent")
//
// Events can be INSTANT, or can be pairs of BEGIN and END in the same scope:
//   TRACE_EVENT_BEGIN0("MY_SUBSYSTEM", "SomethingCostly")
//   doSomethingCostly()
//   TRACE_EVENT_END0("MY_SUBSYSTEM", "SomethingCostly")
// Note: our tools can't always determine the correct BEGIN/END pairs unless
// these are used in the same scope. Use ASYNC_BEGIN/ASYNC_END macros if you
// need them to be in separate scopes.
//
// A common use case is to trace entire function scopes. This
// issues a trace BEGIN and END automatically:
//   void doSomethingCostly() {
//     TRACE_EVENT0("MY_SUBSYSTEM", "doSomethingCostly");
//     ...
//   }
//
// Additional parameters can be associated with an event:
//   void doSomethingCostly2(int howMuch) {
//     TRACE_EVENT1("MY_SUBSYSTEM", "doSomethingCostly",
//         "howMuch", howMuch);
//     ...
//   }
//
// The trace system will automatically add to this information the
// current process id, thread id, and a timestamp in microseconds.
//
// To trace an asynchronous procedure such as an IPC send/receive, use
// ASYNC_BEGIN and ASYNC_END:
//   [single threaded sender code]
//     static int send_count = 0;
//     ++send_count;
//     TRACE_EVENT_ASYNC_BEGIN0("ipc", "message", send_count);
//     Send(new MyMessage(send_count));
//   [receive code]
//     void OnMyMessage(send_count) {
//       TRACE_EVENT_ASYNC_END0("ipc", "message", send_count);
//     }
// The third parameter is a unique ID to match ASYNC_BEGIN/ASYNC_END pairs.
// ASYNC_BEGIN and ASYNC_END can occur on any thread of any traced process.
// Pointers can be used for the ID parameter, and they will be mangled
// internally so that the same pointer on two different processes will not
// match. For example:
//   class MyTracedClass {
//    public:
//     MyTracedClass() {
//       TRACE_EVENT_ASYNC_BEGIN0("category", "MyTracedClass", this);
//     }
//     ~MyTracedClass() {
//       TRACE_EVENT_ASYNC_END0("category", "MyTracedClass", this);
//     }
//   }
//
// Trace event also supports counters, which is a way to track a quantity
// as it varies over time. Counters are created with the following macro:
//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter", g_myCounterValue);
//
// Counters are process-specific. The macro itself can be issued from any
// thread, however.
//
// Sometimes, you want to track two counters at once. You can do this with two
// counter macros:
//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter0", g_myCounterValue[0]);
//   TRACE_COUNTER1("MY_SUBSYSTEM", "myCounter1", g_myCounterValue[1]);
// Or you can do it with a combined macro:
//   TRACE_COUNTER2("MY_SUBSYSTEM", "myCounter",
//       "bytesPinned", g_myCounterValue[0],
//       "bytesAllocated", g_myCounterValue[1]);
// This indicates to the tracing UI that these counters should be displayed
// in a single graph, as a summed area chart.
//
// Since counters are in a global namespace, you may want to disembiguate with a
// unique ID, by using the TRACE_COUNTER_ID* variations.
//
// By default, trace collection is compiled in, but turned off at runtime.
// Collecting trace data is the responsibility of the embedding
// application. In Chrome's case, navigating to about:tracing will turn on
// tracing and display data collected across all active processes.
//
//
// Memory scoping note:
// Tracing copies the pointers, not the string content, of the strings passed
// in for category, name, and arg_names.  Thus, the following code will
// cause problems:
//     char* str = strdup("impprtantName");
//     TRACE_EVENT_INSTANT0("SUBSYSTEM", str);  // BAD!
//     free(str);                   // Trace system now has dangling pointer
//
// To avoid this issue with the |name| and |arg_name| parameters, use the
// TRACE_EVENT_COPY_XXX overloads of the macros at additional runtime overhead.
// Notes: The category must always be in a long-lived char* (i.e. static const).
//        The |arg_values|, when used, are always deep copied with the _COPY
//        macros.
//
// When are string argument values copied:
// const char* arg_values are only referenced by default:
//     TRACE_EVENT1("category", "name",
//                  "arg1", "literal string is only referenced");
// Use TRACE_STR_COPY to force copying of a const char*:
//     TRACE_EVENT1("category", "name",
//                  "arg1", TRACE_STR_COPY("string will be copied"));
// std::string arg_values are always copied:
//     TRACE_EVENT1("category", "name",
//                  "arg1", std::string("string will be copied"));
//
//
// Thread Safety:
// Thread safety is provided by methods defined in event_tracer.h. See the file
// for details.

// By default, const char* argument values are assumed to have long-lived scope
// and will not be copied. Use this macro to force a const char* to be copied.
#define TRACE_STR_COPY(str) \
    webrtc::trace_event_internal::TraceStringWithCopy(str)

// This will mark the trace event as disabled by default. The user will need
// to explicitly enable the event.
#define TRACE_DISABLED_BY_DEFAULT(name) "disabled-by-default-" name

// By default, uint64 ID argument values are not mangled with the Process ID in
// TRACE_EVENT_ASYNC macros. Use this macro to force Process ID mangling.
#define TRACE_ID_MANGLE(id) \
    webrtc::trace_event_internal::TraceID::ForceMangle(id)

// Records a pair of begin and end events called "name" for the current
// scope, with 0, 1 or 2 associated arguments. If the category is not
// enabled, then this does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_EVENT0(category, name) \
    INTERNAL_TRACE_EVENT_ADD_SCOPED(category, name)
#define TRACE_EVENT1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_SCOPED(category, name, arg1_name, arg1_val)
#define TRACE_EVENT2(category, name, arg1_name, arg1_val, arg2_name, arg2_val) \
    INTERNAL_TRACE_EVENT_ADD_SCOPED(category, name, arg1_name, arg1_val,       \
        arg2_name, arg2_val)

// Records a single event called "name" immediately, with 0, 1 or 2
// associated arguments. If the category is not enabled, then this
// does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_EVENT_INSTANT0(category, name)            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, \
        category, name, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_INSTANT1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT,           \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_INSTANT2(category, name, arg1_name, arg1_val,   \
    arg2_name, arg2_val)                                            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT,             \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, \
        arg2_name, arg2_val)
#define TRACE_EVENT_COPY_INSTANT0(category, name)       \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT, \
        category, name, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_INSTANT1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT,                \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
#define TRACE_EVENT_COPY_INSTANT2(category, name, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                               \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_INSTANT,                \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,    \
        arg2_name, arg2_val)

// Records a single BEGIN event called "name" immediately, with 0, 1 or 2
// associated arguments. If the category is not enabled, then this
// does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_EVENT_BEGIN0(category, name)            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, \
        category, name, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_BEGIN1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN,           \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_BEGIN2(category, name, arg1_name, arg1_val,     \
    arg2_name, arg2_val)                                            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN,               \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, \
        arg2_name, arg2_val)
#define TRACE_EVENT_COPY_BEGIN0(category, name)       \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN, \
        category, name, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_BEGIN1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN,                \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
#define TRACE_EVENT_COPY_BEGIN2(category, name, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                             \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_BEGIN,                \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val,  \
        arg2_name, arg2_val)

// Records a single END event for "name" immediately. If the category
// is not enabled, then this does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_EVENT_END0(category, name)            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, \
        category, name, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_END1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END,           \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_END2(category, name, arg1_name, arg1_val,       \
    arg2_name, arg2_val)                                            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END,                 \
        category, name, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val, \
        arg2_name, arg2_val)
#define TRACE_EVENT_COPY_END0(category, name)       \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END, \
        category, name, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_END1(category, name, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END,                \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val)
#define TRACE_EVENT_COPY_END2(category, name, arg1_name, arg1_val,  \
    arg2_name, arg2_val)                                            \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_END,                 \
        category, name, TRACE_EVENT_FLAG_COPY, arg1_name, arg1_val, \
        arg2_name, arg2_val)

// Records the value of a counter called "name" immediately. Value
// must be representable as a 32 bit integer.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_COUNTER1(category, name, value)           \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, \
        category, name, TRACE_EVENT_FLAG_NONE,          \
        "value", static_cast<int>(value))
#define TRACE_COPY_COUNTER1(category, name, value)      \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER, \
        category, name, TRACE_EVENT_FLAG_COPY,          \
        "value", static_cast<int>(value))

// Records the values of a multi-parted counter called "name" immediately.
// The UI will treat value1 and value2 as parts of a whole, displaying their
// values as a stacked-bar chart.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
#define TRACE_COUNTER2(category, name, value1_name, value1_val, \
    value2_name, value2_val)                                    \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER,         \
        category, name, TRACE_EVENT_FLAG_NONE,                  \
        value1_name, static_cast<int>(value1_val),              \
        value2_name, static_cast<int>(value2_val))
#define TRACE_COPY_COUNTER2(category, name, value1_name, value1_val, \
    value2_name, value2_val)                                         \
    INTERNAL_TRACE_EVENT_ADD(TRACE_EVENT_PHASE_COUNTER,              \
        category, name, TRACE_EVENT_FLAG_COPY,                       \
        value1_name, static_cast<int>(value1_val),                   \
        value2_name, static_cast<int>(value2_val))

// Records the value of a counter called "name" immediately. Value
// must be representable as a 32 bit integer.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
// - |id| is used to disambiguate counters with the same name. It must either
//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
//   will be xored with a hash of the process ID so that the same pointer on
//   two different processes will not collide.
#define TRACE_COUNTER_ID1(category, name, id, value)            \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, \
        category, name, id, TRACE_EVENT_FLAG_NONE,              \
        "value", static_cast<int>(value))
#define TRACE_COPY_COUNTER_ID1(category, name, id, value)       \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER, \
        category, name, id, TRACE_EVENT_FLAG_COPY,              \
        "value", static_cast<int>(value))

// Records the values of a multi-parted counter called "name" immediately.
// The UI will treat value1 and value2 as parts of a whole, displaying their
// values as a stacked-bar chart.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
// - |id| is used to disambiguate counters with the same name. It must either
//   be a pointer or an integer value up to 64 bits. If it's a pointer, the bits
//   will be xored with a hash of the process ID so that the same pointer on
//   two different processes will not collide.
#define TRACE_COUNTER_ID2(category, name, id, value1_name, value1_val, \
    value2_name, value2_val)                                           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER,        \
        category, name, id, TRACE_EVENT_FLAG_NONE,                     \
        value1_name, static_cast<int>(value1_val),                     \
        value2_name, static_cast<int>(value2_val))
#define TRACE_COPY_COUNTER_ID2(category, name, id, value1_name, value1_val, \
    value2_name, value2_val)                                                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_COUNTER,             \
        category, name, id, TRACE_EVENT_FLAG_COPY,                          \
        value1_name, static_cast<int>(value1_val),                          \
        value2_name, static_cast<int>(value2_val))

// Records a single ASYNC_BEGIN event called "name" immediately, with 0, 1 or 2
// associated arguments. If the category is not enabled, then this
// does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
// - |id| is used to match the ASYNC_BEGIN event with the ASYNC_END event. ASYNC
//   events are considered to match if their category, name and id values all
//   match. |id| must either be a pointer or an integer value up to 64 bits. If
//   it's a pointer, the bits will be xored with a hash of the process ID so
//   that the same pointer on two different processes will not collide.
// An asynchronous operation can consist of multiple phases. The first phase is
// defined by the ASYNC_BEGIN calls. Additional phases can be defined using the
// ASYNC_STEP macros. When the operation completes, call ASYNC_END.
// An ASYNC trace typically occur on a single thread (if not, they will only be
// drawn on the thread defined in the ASYNC_BEGIN event), but all events in that
// operation must use the same |name| and |id|. Each event can have its own
// args.
#define TRACE_EVENT_ASYNC_BEGIN0(category, name, id)                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
        category, name, id, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_ASYNC_BEGIN1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,       \
        category, name, id, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_ASYNC_BEGIN2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                  \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,       \
        category, name, id, TRACE_EVENT_FLAG_NONE,                        \
        arg1_name, arg1_val, arg2_name, arg2_val)
#define TRACE_EVENT_COPY_ASYNC_BEGIN0(category, name, id)           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN, \
        category, name, id, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_ASYNC_BEGIN1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                             \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_ASYNC_BEGIN2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                       \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_BEGIN,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                             \
        arg1_name, arg1_val, arg2_name, arg2_val)

// Records a single ASYNC_STEP event for |step| immediately. If the category
// is not enabled, then this does nothing. The |name| and |id| must match the
// ASYNC_BEGIN event above. The |step| param identifies this step within the
// async event. This should be called at the beginning of the next phase of an
// asynchronous operation.
#define TRACE_EVENT_ASYNC_STEP0(category, name, id, step)          \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP, \
        category, name, id, TRACE_EVENT_FLAG_NONE, "step", step)
#define TRACE_EVENT_ASYNC_STEP1(category, name, id, step,          \
    arg1_name, arg1_val)                                           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP, \
        category, name, id, TRACE_EVENT_FLAG_NONE, "step", step,   \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_ASYNC_STEP0(category, name, id, step)     \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP, \
        category, name, id, TRACE_EVENT_FLAG_COPY, "step", step)
#define TRACE_EVENT_COPY_ASYNC_STEP1(category, name, id, step,     \
    arg1_name, arg1_val)                                           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_STEP, \
        category, name, id, TRACE_EVENT_FLAG_COPY, "step", step,   \
        arg1_name, arg1_val)

// Records a single ASYNC_END event for "name" immediately. If the category
// is not enabled, then this does nothing.
#define TRACE_EVENT_ASYNC_END0(category, name, id)                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
        category, name, id, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_ASYNC_END1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,       \
        category, name, id, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_ASYNC_END2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,       \
        category, name, id, TRACE_EVENT_FLAG_NONE,                      \
        arg1_name, arg1_val, arg2_name, arg2_val)
#define TRACE_EVENT_COPY_ASYNC_END0(category, name, id)           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END, \
        category, name, id, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_ASYNC_END1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                           \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_ASYNC_END2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                     \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_ASYNC_END,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                           \
        arg1_name, arg1_val, arg2_name, arg2_val)

// Records a single FLOW_BEGIN event called "name" immediately, with 0, 1 or 2
// associated arguments. If the category is not enabled, then this
// does nothing.
// - category and name strings must have application lifetime (statics or
//   literals). They may not include " chars.
// - |id| is used to match the FLOW_BEGIN event with the FLOW_END event. FLOW
//   events are considered to match if their category, name and id values all
//   match. |id| must either be a pointer or an integer value up to 64 bits. If
//   it's a pointer, the bits will be xored with a hash of the process ID so
//   that the same pointer on two different processes will not collide.
// FLOW events are different from ASYNC events in how they are drawn by the
// tracing UI. A FLOW defines asynchronous data flow, such as posting a task
// (FLOW_BEGIN) and later executing that task (FLOW_END). Expect FLOWs to be
// drawn as lines or arrows from FLOW_BEGIN scopes to FLOW_END scopes. Similar
// to ASYNC, a FLOW can consist of multiple phases. The first phase is defined
// by the FLOW_BEGIN calls. Additional phases can be defined using the FLOW_STEP
// macros. When the operation completes, call FLOW_END. An async operation can
// span threads and processes, but all events in that operation must use the
// same |name| and |id|. Each event can have its own args.
#define TRACE_EVENT_FLOW_BEGIN0(category, name, id)                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
        category, name, id, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,       \
        category, name, id, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                 \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,       \
        category, name, id, TRACE_EVENT_FLAG_NONE,                       \
        arg1_name, arg1_val, arg2_name, arg2_val)
#define TRACE_EVENT_COPY_FLOW_BEGIN0(category, name, id)           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN, \
        category, name, id, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_FLOW_BEGIN1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                            \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_FLOW_BEGIN2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                      \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_BEGIN,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                            \
        arg1_name, arg1_val, arg2_name, arg2_val)

// Records a single FLOW_STEP event for |step| immediately. If the category
// is not enabled, then this does nothing. The |name| and |id| must match the
// FLOW_BEGIN event above. The |step| param identifies this step within the
// async event. This should be called at the beginning of the next phase of an
// asynchronous operation.
#define TRACE_EVENT_FLOW_STEP0(category, name, id, step)          \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
        category, name, id, TRACE_EVENT_FLAG_NONE, "step", step)
#define TRACE_EVENT_FLOW_STEP1(category, name, id, step,          \
    arg1_name, arg1_val)                                          \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
        category, name, id, TRACE_EVENT_FLAG_NONE, "step", step,  \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_FLOW_STEP0(category, name, id, step)     \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
        category, name, id, TRACE_EVENT_FLAG_COPY, "step", step)
#define TRACE_EVENT_COPY_FLOW_STEP1(category, name, id, step,     \
    arg1_name, arg1_val)                                          \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_STEP, \
        category, name, id, TRACE_EVENT_FLAG_COPY, "step", step,  \
        arg1_name, arg1_val)

// Records a single FLOW_END event for "name" immediately. If the category
// is not enabled, then this does nothing.
#define TRACE_EVENT_FLOW_END0(category, name, id)                \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, \
        category, name, id, TRACE_EVENT_FLAG_NONE)
#define TRACE_EVENT_FLOW_END1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END,       \
        category, name, id, TRACE_EVENT_FLAG_NONE, arg1_name, arg1_val)
#define TRACE_EVENT_FLOW_END2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                               \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END,       \
        category, name, id, TRACE_EVENT_FLAG_NONE,                     \
        arg1_name, arg1_val, arg2_name, arg2_val)
#define TRACE_EVENT_COPY_FLOW_END0(category, name, id)           \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END, \
        category, name, id, TRACE_EVENT_FLAG_COPY)
#define TRACE_EVENT_COPY_FLOW_END1(category, name, id, arg1_name, arg1_val) \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                          \
        arg1_name, arg1_val)
#define TRACE_EVENT_COPY_FLOW_END2(category, name, id, arg1_name, arg1_val, \
    arg2_name, arg2_val)                                                    \
    INTERNAL_TRACE_EVENT_ADD_WITH_ID(TRACE_EVENT_PHASE_FLOW_END,            \
        category, name, id, TRACE_EVENT_FLAG_COPY,                          \
        arg1_name, arg1_val, arg2_name, arg2_val)

////////////////////////////////////////////////////////////////////////////////
// Implementation specific tracing API definitions.

// Get a pointer to the enabled state of the given trace category. Only
// long-lived literal strings should be given as the category name. The returned
// pointer can be held permanently in a local static for example. If the
// unsigned char is non-zero, tracing is enabled. If tracing is enabled,
// TRACE_EVENT_API_ADD_TRACE_EVENT can be called. It's OK if tracing is disabled
// between the load of the tracing state and the call to
// TRACE_EVENT_API_ADD_TRACE_EVENT, because this flag only provides an early out
// for best performance when tracing is disabled.
// const unsigned char*
//     TRACE_EVENT_API_GET_CATEGORY_ENABLED(const char* category_name)
#define TRACE_EVENT_API_GET_CATEGORY_ENABLED \
    webrtc::EventTracer::GetCategoryEnabled

// Add a trace event to the platform tracing system.
// void TRACE_EVENT_API_ADD_TRACE_EVENT(
//                    char phase,
//                    const unsigned char* category_enabled,
//                    const char* name,
//                    unsigned long long id,
//                    int num_args,
//                    const char** arg_names,
//                    const unsigned char* arg_types,
//                    const unsigned long long* arg_values,
//                    unsigned char flags)
#define TRACE_EVENT_API_ADD_TRACE_EVENT webrtc::EventTracer::AddTraceEvent

////////////////////////////////////////////////////////////////////////////////

// Implementation detail: trace event macros create temporary variables
// to keep instrumentation overhead low. These macros give each temporary
// variable a unique name based on the line number to prevent name collissions.
#define INTERNAL_TRACE_EVENT_UID3(a, b) \
    trace_event_unique_##a##b
#define INTERNAL_TRACE_EVENT_UID2(a, b) \
    INTERNAL_TRACE_EVENT_UID3(a, b)
#define INTERNAL_TRACE_EVENT_UID(name_prefix) \
    INTERNAL_TRACE_EVENT_UID2(name_prefix, __LINE__)

#if WEBRTC_NON_STATIC_TRACE_EVENT_HANDLERS
#define INTERNAL_TRACE_EVENT_INFO_TYPE const unsigned char*
#else
#define INTERNAL_TRACE_EVENT_INFO_TYPE static const unsigned char*
#endif // WEBRTC_NON_STATIC_TRACE_EVENT_HANDLERS

// Implementation detail: internal macro to create static category.
#define INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category) \
    INTERNAL_TRACE_EVENT_INFO_TYPE INTERNAL_TRACE_EVENT_UID(catstatic) = TRACE_EVENT_API_GET_CATEGORY_ENABLED(category);

// Implementation detail: internal macro to create static category and add
// event if the category is enabled.
#define INTERNAL_TRACE_EVENT_ADD(phase, category, name, flags, ...)              \
    do                                                                           \
    {                                                                            \
        INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category);                        \
        if (*INTERNAL_TRACE_EVENT_UID(catstatic))                                \
        {                                                                        \
            webrtc::trace_event_internal::AddTraceEvent(                         \
                phase, INTERNAL_TRACE_EVENT_UID(catstatic), name,                \
                webrtc::trace_event_internal::kNoEventId, flags, ##__VA_ARGS__); \
        }                                                                        \
    } while (0)

// Implementation detail: internal macro to create static category and add begin
// event if the category is enabled. Also adds the end event when the scope
// ends.
#define INTERNAL_TRACE_EVENT_ADD_SCOPED(category, name, ...)                                          \
    INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category);                                                 \
    webrtc::trace_event_internal::TraceEndOnScopeClose                                                \
        INTERNAL_TRACE_EVENT_UID(profileScope);                                                       \
    if (*INTERNAL_TRACE_EVENT_UID(catstatic))                                                         \
    {                                                                                                 \
        webrtc::trace_event_internal::AddTraceEvent(                                                  \
            TRACE_EVENT_PHASE_BEGIN,                                                                  \
            INTERNAL_TRACE_EVENT_UID(catstatic),                                                      \
            name, webrtc::trace_event_internal::kNoEventId,                                           \
            TRACE_EVENT_FLAG_NONE, ##__VA_ARGS__);                                                    \
        INTERNAL_TRACE_EVENT_UID(profileScope).Initialize(INTERNAL_TRACE_EVENT_UID(catstatic), name); \
    }

// Implementation detail: internal macro to create static category and add
// event if the category is enabled.
#define INTERNAL_TRACE_EVENT_ADD_WITH_ID(phase, category, name, id, flags,     \
    ...)                                                                       \
    do                                                                         \
    {                                                                          \
        INTERNAL_TRACE_EVENT_GET_CATEGORY_INFO(category);                      \
        if (*INTERNAL_TRACE_EVENT_UID(catstatic))                              \
        {                                                                      \
            unsigned char trace_event_flags = flags | TRACE_EVENT_FLAG_HAS_ID; \
            webrtc::trace_event_internal::TraceID trace_event_trace_id(        \
                id, &trace_event_flags);                                       \
            webrtc::trace_event_internal::AddTraceEvent(                       \
                phase, INTERNAL_TRACE_EVENT_UID(catstatic),                    \
                name, trace_event_trace_id.data(), trace_event_flags,          \
                ##__VA_ARGS__);                                                \
        }                                                                      \
    } while (0)

// Notes regarding the following definitions:
// New values can be added and propagated to third party libraries, but existing
// definitions must never be changed, because third party libraries may use old
// definitions.

// Phase indicates the nature of an event entry. E.g. part of a begin/end pair.
#define TRACE_EVENT_PHASE_BEGIN ('B')
#define TRACE_EVENT_PHASE_END ('E')
#define TRACE_EVENT_PHASE_INSTANT ('I')
#define TRACE_EVENT_PHASE_ASYNC_BEGIN ('S')
#define TRACE_EVENT_PHASE_ASYNC_STEP ('T')
#define TRACE_EVENT_PHASE_ASYNC_END ('F')
#define TRACE_EVENT_PHASE_FLOW_BEGIN ('s')
#define TRACE_EVENT_PHASE_FLOW_STEP ('t')
#define TRACE_EVENT_PHASE_FLOW_END ('f')
#define TRACE_EVENT_PHASE_METADATA ('M')
#define TRACE_EVENT_PHASE_COUNTER ('C')

// Flags for changing the behavior of TRACE_EVENT_API_ADD_TRACE_EVENT.
#define TRACE_EVENT_FLAG_NONE (static_cast<unsigned char>(0))
#define TRACE_EVENT_FLAG_COPY (static_cast<unsigned char>(1 << 0))
#define TRACE_EVENT_FLAG_HAS_ID (static_cast<unsigned char>(1 << 1))
#define TRACE_EVENT_FLAG_MANGLE_ID (static_cast<unsigned char>(1 << 2))

// Type values for identifying types in the TraceValue union.
#define TRACE_VALUE_TYPE_BOOL (static_cast<unsigned char>(1))
#define TRACE_VALUE_TYPE_UINT (static_cast<unsigned char>(2))
#define TRACE_VALUE_TYPE_INT (static_cast<unsigned char>(3))
#define TRACE_VALUE_TYPE_DOUBLE (static_cast<unsigned char>(4))
#define TRACE_VALUE_TYPE_POINTER (static_cast<unsigned char>(5))
#define TRACE_VALUE_TYPE_STRING (static_cast<unsigned char>(6))
#define TRACE_VALUE_TYPE_COPY_STRING (static_cast<unsigned char>(7))

namespace webrtc
{
namespace trace_event_internal
{

    // Specify these values when the corresponding argument of AddTraceEvent is not
    // used.
    const int kZeroNumArgs = 0;
    const unsigned long long kNoEventId = 0;

    // TraceID encapsulates an ID that can either be an integer or pointer. Pointers
    // are mangled with the Process ID so that they are unlikely to collide when the
    // same pointer is used on different processes.
    class TraceID
    {
    public:
        class ForceMangle
        {
        public:
            explicit ForceMangle(unsigned long long id)
                : data_(id)
            {
            }
            explicit ForceMangle(unsigned long id)
                : data_(id)
            {
            }
            explicit ForceMangle(unsigned int id)
                : data_(id)
            {
            }
            explicit ForceMangle(unsigned short id)
                : data_(id)
            {
            }
            explicit ForceMangle(unsigned char id)
                : data_(id)
            {
            }
            explicit ForceMangle(long long id)
                : data_(static_cast<unsigned long long>(id))
            {
            }
            explicit ForceMangle(long id)
                : data_(static_cast<unsigned long long>(id))
            {
            }
            explicit ForceMangle(int id)
                : data_(static_cast<unsigned long long>(id))
            {
            }
            explicit ForceMangle(short id)
                : data_(static_cast<unsigned long long>(id))
            {
            }
            explicit ForceMangle(signed char id)
                : data_(static_cast<unsigned long long>(id))
            {
            }

            unsigned long long data() const { return data_; }

        private:
            unsigned long long data_;
        };

        explicit TraceID(const void* id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(
                reinterpret_cast<uintptr_t>(id)))
        {
            *flags |= TRACE_EVENT_FLAG_MANGLE_ID;
        }
        explicit TraceID(ForceMangle id, unsigned char* flags)
            : data_(id.data())
        {
            *flags |= TRACE_EVENT_FLAG_MANGLE_ID;
        }
        explicit TraceID(unsigned long long id, unsigned char* flags)
            : data_(id)
        {
            (void)flags;
        }
        explicit TraceID(unsigned long id, unsigned char* flags)
            : data_(id)
        {
            (void)flags;
        }
        explicit TraceID(unsigned int id, unsigned char* flags)
            : data_(id)
        {
            (void)flags;
        }
        explicit TraceID(unsigned short id, unsigned char* flags)
            : data_(id)
        {
            (void)flags;
        }
        explicit TraceID(unsigned char id, unsigned char* flags)
            : data_(id)
        {
            (void)flags;
        }
        explicit TraceID(long long id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(id))
        {
            (void)flags;
        }
        explicit TraceID(long id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(id))
        {
            (void)flags;
        }
        explicit TraceID(int id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(id))
        {
            (void)flags;
        }
        explicit TraceID(short id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(id))
        {
            (void)flags;
        }
        explicit TraceID(signed char id, unsigned char* flags)
            : data_(static_cast<unsigned long long>(id))
        {
            (void)flags;
        }

        unsigned long long data() const { return data_; }

    private:
        unsigned long long data_;
    };

    // Simple union to store various types as unsigned long long.
    union TraceValueUnion {
        bool as_bool;
        unsigned long long as_uint;
        long long as_int;
        double as_double;
        const void* as_pointer;
        const char* as_string;
    };

    // Simple container for const char* that should be copied instead of retained.
    class TraceStringWithCopy
    {
    public:
        explicit TraceStringWithCopy(const char* str)
            : str_(str)
        {
        }
        operator const char*() const { return str_; }

    private:
        const char* str_;
    };

// Define SetTraceValue for each allowed type. It stores the type and
// value in the return arguments. This allows this API to avoid declaring any
// structures so that it is portable to third_party libraries.
#define INTERNAL_DECLARE_SET_TRACE_VALUE(actual_type, \
    union_member,                                     \
    value_type_id)                                    \
    static inline void SetTraceValue(actual_type arg, \
        unsigned char* type,                          \
        unsigned long long* value)                    \
    {                                                 \
        TraceValueUnion type_value;                   \
        type_value.union_member = arg;                \
        *type = value_type_id;                        \
        *value = type_value.as_uint;                  \
    }
// Simpler form for int types that can be safely casted.
#define INTERNAL_DECLARE_SET_TRACE_VALUE_INT(actual_type, \
    value_type_id)                                        \
    static inline void SetTraceValue(actual_type arg,     \
        unsigned char* type,                              \
        unsigned long long* value)                        \
    {                                                     \
        *type = value_type_id;                            \
        *value = static_cast<unsigned long long>(arg);    \
    }

    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned long long, TRACE_VALUE_TYPE_UINT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned long, TRACE_VALUE_TYPE_UINT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned int, TRACE_VALUE_TYPE_UINT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned short, TRACE_VALUE_TYPE_UINT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(unsigned char, TRACE_VALUE_TYPE_UINT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(long long, TRACE_VALUE_TYPE_INT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(long, TRACE_VALUE_TYPE_INT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(int, TRACE_VALUE_TYPE_INT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(short, TRACE_VALUE_TYPE_INT)
    INTERNAL_DECLARE_SET_TRACE_VALUE_INT(signed char, TRACE_VALUE_TYPE_INT)
    INTERNAL_DECLARE_SET_TRACE_VALUE(bool, as_bool, TRACE_VALUE_TYPE_BOOL)
    INTERNAL_DECLARE_SET_TRACE_VALUE(double, as_double, TRACE_VALUE_TYPE_DOUBLE)
    INTERNAL_DECLARE_SET_TRACE_VALUE(const void*, as_pointer,
        TRACE_VALUE_TYPE_POINTER)
    INTERNAL_DECLARE_SET_TRACE_VALUE(const char*, as_string,
        TRACE_VALUE_TYPE_STRING)
    INTERNAL_DECLARE_SET_TRACE_VALUE(const TraceStringWithCopy&, as_string,
        TRACE_VALUE_TYPE_COPY_STRING)

#undef INTERNAL_DECLARE_SET_TRACE_VALUE
#undef INTERNAL_DECLARE_SET_TRACE_VALUE_INT

    // std::string version of SetTraceValue so that trace arguments can be strings.
    static inline void SetTraceValue(const std::string& arg,
        unsigned char* type,
        unsigned long long* value)
    {
        TraceValueUnion type_value;
        type_value.as_string = arg.c_str();
        *type = TRACE_VALUE_TYPE_COPY_STRING;
        *value = type_value.as_uint;
    }

    // These AddTraceEvent template functions are defined here instead of in the
    // macro, because the arg_values could be temporary objects, such as
    // std::string. In order to store pointers to the internal c_str and pass
    // through to the tracing API, the arg_values must live throughout
    // these procedures.

    static inline void AddTraceEvent(char phase,
        const unsigned char* category_enabled,
        const char* name,
        unsigned long long id,
        unsigned char flags)
    {
        TRACE_EVENT_API_ADD_TRACE_EVENT(phase, category_enabled, name, id,
            kZeroNumArgs, nullptr, nullptr, nullptr,
            flags);
    }

    template <class ARG1_TYPE>
    static inline void AddTraceEvent(char phase,
        const unsigned char* category_enabled,
        const char* name,
        unsigned long long id,
        unsigned char flags,
        const char* arg1_name,
        const ARG1_TYPE& arg1_val)
    {
        const int num_args = 1;
        unsigned char arg_types[1];
        unsigned long long arg_values[1];
        SetTraceValue(arg1_val, &arg_types[0], &arg_values[0]);
        TRACE_EVENT_API_ADD_TRACE_EVENT(
            phase, category_enabled, name, id,
            num_args, &arg1_name, arg_types, arg_values,
            flags);
    }

    template <class ARG1_TYPE, class ARG2_TYPE>
    static inline void AddTraceEvent(char phase,
        const unsigned char* category_enabled,
        const char* name,
        unsigned long long id,
        unsigned char flags,
        const char* arg1_name,
        const ARG1_TYPE& arg1_val,
        const char* arg2_name,
        const ARG2_TYPE& arg2_val)
    {
        const int num_args = 2;
        const char* arg_names[2] = {arg1_name, arg2_name};
        unsigned char arg_types[2];
        unsigned long long arg_values[2];
        SetTraceValue(arg1_val, &arg_types[0], &arg_values[0]);
        SetTraceValue(arg2_val, &arg_types[1], &arg_values[1]);
        TRACE_EVENT_API_ADD_TRACE_EVENT(
            phase, category_enabled, name, id,
            num_args, arg_names, arg_types, arg_values,
            flags);
    }

    // Used by TRACE_EVENTx macro. Do not use directly.
    class TraceEndOnScopeClose
    {
    public:
        // Note: members of data_ intentionally left uninitialized. See Initialize.
        TraceEndOnScopeClose()
            : p_data_(nullptr)
        {
        }
        ~TraceEndOnScopeClose()
        {
            if (p_data_)
                AddEventIfEnabled();
        }

        void Initialize(const unsigned char* category_enabled,
            const char* name)
        {
            data_.category_enabled = category_enabled;
            data_.name = name;
            p_data_ = &data_;
        }

    private:
        // Add the end event if the category is still enabled.
        void AddEventIfEnabled()
        {
            // Only called when p_data_ is non-null.
            if (*p_data_->category_enabled)
            {
                TRACE_EVENT_API_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_END,
                    p_data_->category_enabled, p_data_->name,
                    kNoEventId, kZeroNumArgs, nullptr,
                    nullptr, nullptr, TRACE_EVENT_FLAG_NONE);
            }
        }

        // This Data struct workaround is to avoid initializing all the members
        // in Data during construction of this object, since this object is always
        // constructed, even when tracing is disabled. If the members of Data were
        // members of this class instead, compiler warnings occur about potential
        // uninitialized accesses.
        struct Data
        {
            const unsigned char* category_enabled;
            const char* name;
        };
        Data* p_data_;
        Data data_;
    };

} // namespace trace_event_internal
} // namespace webrtc

#endif // RTC_BASE_TRACE_EVENT_H_