Merge "Exporting C++ headers from system/core" am: 812b7d5d52 am: f484dd3401

am: a252f11da3

Change-Id: If2dc2da283db7a60f478c6e61a9e9b32edb42ce7

1 files changed, 72 insertions, 0 deletions

diff --git a/libutils/include/utils/Log.h b/libutils/include/utils/Log.h
new file mode 100644
index 000000000..5276a498d
--- /dev/null
+++ b/libutils/include/utils/Log.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2005 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//
+// C/C++ logging functions.  See the logging documentation for API details.
+//
+// We'd like these to be available from C code (in case we import some from
+// somewhere), so this has a C interface.
+//
+// The output will be correct when the log file is shared between multiple
+// threads and/or multiple processes so long as the operating system
+// supports O_APPEND.  These calls have mutex-protected data structures
+// and so are NOT reentrant.  Do not use LOG in a signal handler.
+//
+#ifndef _LIBS_UTILS_LOG_H
+#define _LIBS_UTILS_LOG_H
+
+#include <sys/types.h>
+
+#include <log/log.h>
+
+#ifdef __cplusplus
+
+namespace android {
+
+/*
+ * A very simple utility that yells in the log when an operation takes too long.
+ */
+class LogIfSlow {
+public:
+    LogIfSlow(const char* tag, android_LogPriority priority,
+            int timeoutMillis, const char* message);
+    ~LogIfSlow();
+
+private:
+    const char* const mTag;
+    const android_LogPriority mPriority;
+    const int mTimeoutMillis;
+    const char* const mMessage;
+    const int64_t mStart;
+};
+
+/*
+ * Writes the specified debug log message if this block takes longer than the
+ * specified number of milliseconds to run.  Includes the time actually taken.
+ *
+ * {
+ *     ALOGD_IF_SLOW(50, "Excessive delay doing something.");
+ *     doSomething();
+ * }
+ */
+#define ALOGD_IF_SLOW(timeoutMillis, message) \
+    android::LogIfSlow _logIfSlow(LOG_TAG, ANDROID_LOG_DEBUG, timeoutMillis, message);
+
+} // namespace android
+
+#endif // __cplusplus
+
+#endif // _LIBS_UTILS_LOG_H