blob: da2fb7689ca726a8e6869c1e9bc966b9a7852be6 [file] [log] [blame]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/test/trace_to_file.h"
#include "base/base_switches.h"
#include "base/command_line.h"
#include "base/files/file_util.h"
#include "base/functional/bind.h"
#include "base/memory/ref_counted_memory.h"
#include "base/run_loop.h"
#include "base/task/single_thread_task_runner.h"
#include "base/test/task_environment.h"
#include "base/trace_event/trace_buffer.h"
#include "base/trace_event/trace_log.h"
namespace base {
namespace test {
TraceToFile::TraceToFile() : started_(false) {
}
TraceToFile::~TraceToFile() {
EndTracingIfNeeded();
}
void TraceToFile::BeginTracingFromCommandLineOptions() {
DCHECK(CommandLine::InitializedForCurrentProcess());
DCHECK(!started_);
if (!CommandLine::ForCurrentProcess()->HasSwitch(switches::kTraceToFile))
return;
// Empty filter (i.e. just --trace-to-file) turns into default categories in
// TraceEventImpl
std::string filter = CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
switches::kTraceToFile);
FilePath path;
if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kTraceToFileName)) {
path = FilePath(CommandLine::ForCurrentProcess()
->GetSwitchValuePath(switches::kTraceToFileName));
} else {
path = FilePath(FILE_PATH_LITERAL("trace.json"));
}
BeginTracing(path, filter);
}
void TraceToFile::BeginTracing(const FilePath& path,
const std::string& categories) {
DCHECK(!started_);
started_ = true;
path_ = path;
WriteFileHeader();
trace_event::TraceLog::GetInstance()->SetEnabled(
trace_event::TraceConfig(categories, trace_event::RECORD_UNTIL_FULL),
trace_event::TraceLog::RECORDING_MODE);
}
void TraceToFile::WriteFileHeader() {
WriteFile(path_, "{\"traceEvents\": [");
}
void TraceToFile::AppendFileFooter() {
const char str[] = "]}";
AppendToFile(path_, str);
}
void TraceToFile::TraceOutputCallback(const std::string& data) {
bool ret = AppendToFile(path_, data);
DCHECK(ret);
}
static void OnTraceDataCollected(
OnceClosure quit_closure,
trace_event::TraceResultBuffer* buffer,
const scoped_refptr<RefCountedString>& json_events_str,
bool has_more_events) {
buffer->AddFragment(json_events_str->data());
if (!has_more_events)
std::move(quit_closure).Run();
}
void TraceToFile::EndTracingIfNeeded() {
if (!started_)
return;
started_ = false;
trace_event::TraceLog::GetInstance()->SetDisabled();
trace_event::TraceResultBuffer buffer;
buffer.SetOutputCallback(
BindRepeating(&TraceToFile::TraceOutputCallback, Unretained(this)));
// In tests we might not have a TaskEnvironment, create one if needed.
std::unique_ptr<SingleThreadTaskEnvironment> task_environment;
if (!SingleThreadTaskRunner::HasCurrentDefault())
task_environment = std::make_unique<SingleThreadTaskEnvironment>();
RunLoop run_loop;
trace_event::TraceLog::GetInstance()->Flush(BindRepeating(
&OnTraceDataCollected, run_loop.QuitClosure(), Unretained(&buffer)));
run_loop.Run();
AppendFileFooter();
}
} // namespace test
} // namespace base