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content / public / browser / global_request_id.cc [blame]
// Copyright 2021 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/public/browser/global_request_id.h"
#include <atomic>
#include "base/check_op.h"
#include "base/compiler_specific.h"
#include "third_party/perfetto/include/perfetto/tracing/traced_value.h"
namespace content {
void GlobalRequestID::WriteIntoTrace(perfetto::TracedValue context) const {
auto dict = std::move(context).WriteDictionary();
dict.Add("child_id", child_id);
dict.Add("request_id", request_id);
}
// This method must not be inlined, or it might reuse `request_id` values.
//
// static
NOINLINE GlobalRequestID GlobalRequestID::MakeBrowserInitiated() {
static constinit std::atomic<int32_t> s_next_request_id{-2};
// Note that atomic decrement for signed integral types is defined in terms of
// two's complement. Decrementing the min `int32_t` (0x80000000) will wrap
// around to the max (0x7fffffff). There are no undefined results.
const int32_t request_id = s_next_request_id--;
CHECK_LT(request_id, 0);
return GlobalRequestID(-1, request_id);
}
} // namespace content