Mutex: add timedLock() method
This is not available for host builds because OSX doesn't have
pthread_mutex_timedlock() or equivalent.
Bug: 18842510
Change-Id: I072e74ab1a6f770fd245828b39c5f954dda1113b
diff --git a/include/utils/Mutex.h b/include/utils/Mutex.h
index dd201c8..4fdd27f 100644
--- a/include/utils/Mutex.h
+++ b/include/utils/Mutex.h
@@ -26,6 +26,7 @@
#endif
#include <utils/Errors.h>
+#include <utils/Timers.h>
// ---------------------------------------------------------------------------
namespace android {
@@ -45,7 +46,7 @@
PRIVATE = 0,
SHARED = 1
};
-
+
Mutex();
Mutex(const char* name);
Mutex(int type, const char* name = NULL);
@@ -58,6 +59,16 @@
// lock if possible; returns 0 on success, error otherwise
status_t tryLock();
+#if HAVE_ANDROID_OS
+ // lock the mutex, but don't wait longer than timeoutMilliseconds.
+ // Returns 0 on success, TIMED_OUT for failure due to timeout expiration.
+ //
+ // OSX doesn't have pthread_mutex_timedlock() or equivalent. To keep
+ // capabilities consistent across host OSes, this method is only available
+ // when building Android binaries.
+ status_t timedLock(nsecs_t timeoutMilliseconds);
+#endif
+
// Manages the mutex automatically. It'll be locked when Autolock is
// constructed and released when Autolock goes out of scope.
class Autolock {
@@ -71,11 +82,11 @@
private:
friend class Condition;
-
+
// A mutex cannot be copied
Mutex(const Mutex&);
Mutex& operator = (const Mutex&);
-
+
#if defined(HAVE_PTHREADS)
pthread_mutex_t mMutex;
#else
@@ -117,6 +128,15 @@
inline status_t Mutex::tryLock() {
return -pthread_mutex_trylock(&mMutex);
}
+#if HAVE_ANDROID_OS
+inline status_t Mutex::timedLock(nsecs_t timeoutNs) {
+ const struct timespec ts = {
+ /* .tv_sec = */ timeoutNs / 1000000000,
+ /* .tv_nsec = */ timeoutNs % 1000000000,
+ };
+ return -pthread_mutex_timedlock(&mMutex, &ts);
+}
+#endif
#endif // HAVE_PTHREADS
@@ -127,7 +147,7 @@
* When the function returns, it will go out of scope, and release the
* mutex.
*/
-
+
typedef Mutex::Autolock AutoMutex;
// ---------------------------------------------------------------------------