Add base to the repository.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@8 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 105 insertions, 0 deletions

diff --git a/base/perftimer.h b/base/perftimer.h
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+// Copyright 2008, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef BASE_PERFTTIMER_H__
+#define BASE_PERFTTIMER_H__
+
+#include <string>
+#include "base/basictypes.h"
+#include "base/time.h"
+
+// ----------------------------------------------------------------------
+// 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 char* log_file);
+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_ = TimeTicks::Now();
+  }
+
+  // Returns the time elapsed since object construction
+  TimeDelta Elapsed() const {
+    return TimeTicks::Now() - begin_;
+  }
+
+ private:
+  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_PERFTTIMER_H__