// Copyright (c) 2006-2008 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_PERFTIMER_H_
#define BASE_PERFTIMER_H_
#include <string>
#include "base/basictypes.h"
#include "base/time.h"
class FilePath;
// ----------------------------------------------------------------------
// Initializes and finalizes the perf log. These functions should be
// called at the beginning and end (respectively) of running all the
// performance tests. The init function returns true on success.
// ----------------------------------------------------------------------
bool InitPerfLog(const FilePath& log_path);
void FinalizePerfLog();
// ----------------------------------------------------------------------
// LogPerfResult
// Writes to the perf result log the given 'value' resulting from the
// named 'test'. The units are to aid in reading the log by people.
// ----------------------------------------------------------------------
void LogPerfResult(const char* test_name, double value, const char* units);
// ----------------------------------------------------------------------
// PerfTimer
// A simple wrapper around Now()
// ----------------------------------------------------------------------
class PerfTimer {
public:
PerfTimer() {
begin_ = base::TimeTicks::Now();
}
// Returns the time elapsed since object construction
base::TimeDelta Elapsed() const {
return base::TimeTicks::Now() - begin_;
}
private:
base::TimeTicks begin_;
};
// ----------------------------------------------------------------------
// PerfTimeLogger
// Automates calling LogPerfResult for the common case where you want
// to measure the time that something took. Call Done() when the test
// is complete if you do extra work after the test or there are stack
// objects with potentially expensive constructors. Otherwise, this
// class with automatically log on destruction.
// ----------------------------------------------------------------------
class PerfTimeLogger {
public:
explicit PerfTimeLogger(const char* test_name)
: logged_(false),
test_name_(test_name) {
}
~PerfTimeLogger() {
if (!logged_)
Done();
}
void Done() {
// we use a floating-point millisecond value because it is more
// intuitive than microseconds and we want more precision than
// integer milliseconds
LogPerfResult(test_name_.c_str(), timer_.Elapsed().InMillisecondsF(), "ms");
logged_ = true;
}
private:
bool logged_;
std::string test_name_;
PerfTimer timer_;
};
#endif // BASE_PERFTIMER_H_