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diff --git a/include/utils/Condition.h b/include/utils/Condition.h
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--- /dev/null
+++ b/include/utils/Condition.h
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+/*
+ * Copyright (C) 2007 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.
+ */
+
+#ifndef _LIBS_UTILS_CONDITION_H
+#define _LIBS_UTILS_CONDITION_H
+
+#include <stdint.h>
+#include <sys/types.h>
+#include <time.h>
+
+#if defined(HAVE_PTHREADS)
+# include <pthread.h>
+#endif
+
+#include <utils/Errors.h>
+#include <utils/Mutex.h>
+#include <utils/Timers.h>
+
+// ---------------------------------------------------------------------------
+namespace android {
+// ---------------------------------------------------------------------------
+
+/*
+ * Condition variable class.  The implementation is system-dependent.
+ *
+ * Condition variables are paired up with mutexes.  Lock the mutex,
+ * call wait(), then either re-wait() if things aren't quite what you want,
+ * or unlock the mutex and continue.  All threads calling wait() must
+ * use the same mutex for a given Condition.
+ */
+class Condition {
+public:
+    enum {
+        PRIVATE = 0,
+        SHARED = 1
+    };
+
+    Condition();
+    Condition(int type);
+    ~Condition();
+    // Wait on the condition variable.  Lock the mutex before calling.
+    status_t wait(Mutex& mutex);
+    // same with relative timeout
+    status_t waitRelative(Mutex& mutex, nsecs_t reltime);
+    // Signal the condition variable, allowing one thread to continue.
+    void signal();
+    // Signal the condition variable, allowing all threads to continue.
+    void broadcast();
+
+private:
+#if defined(HAVE_PTHREADS)
+    pthread_cond_t mCond;
+#else
+    void*   mState;
+#endif
+};
+
+// ---------------------------------------------------------------------------
+
+#if defined(HAVE_PTHREADS)
+
+inline Condition::Condition() {
+    pthread_cond_init(&mCond, NULL);
+}
+inline Condition::Condition(int type) {
+    if (type == SHARED) {
+        pthread_condattr_t attr;
+        pthread_condattr_init(&attr);
+        pthread_condattr_setpshared(&attr, PTHREAD_PROCESS_SHARED);
+        pthread_cond_init(&mCond, &attr);
+        pthread_condattr_destroy(&attr);
+    } else {
+        pthread_cond_init(&mCond, NULL);
+    }
+}
+inline Condition::~Condition() {
+    pthread_cond_destroy(&mCond);
+}
+inline status_t Condition::wait(Mutex& mutex) {
+    return -pthread_cond_wait(&mCond, &mutex.mMutex);
+}
+inline status_t Condition::waitRelative(Mutex& mutex, nsecs_t reltime) {
+#if defined(HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE)
+    struct timespec ts;
+    ts.tv_sec  = reltime/1000000000;
+    ts.tv_nsec = reltime%1000000000;
+    return -pthread_cond_timedwait_relative_np(&mCond, &mutex.mMutex, &ts);
+#else // HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE
+    struct timespec ts;
+#if defined(HAVE_POSIX_CLOCKS)
+    clock_gettime(CLOCK_REALTIME, &ts);
+#else // HAVE_POSIX_CLOCKS
+    // we don't support the clocks here.
+    struct timeval t;
+    gettimeofday(&t, NULL);
+    ts.tv_sec = t.tv_sec;
+    ts.tv_nsec= t.tv_usec*1000;
+#endif // HAVE_POSIX_CLOCKS
+    ts.tv_sec += reltime/1000000000;
+    ts.tv_nsec+= reltime%1000000000;
+    if (ts.tv_nsec >= 1000000000) {
+        ts.tv_nsec -= 1000000000;
+        ts.tv_sec  += 1;
+    }
+    return -pthread_cond_timedwait(&mCond, &mutex.mMutex, &ts);
+#endif // HAVE_PTHREAD_COND_TIMEDWAIT_RELATIVE
+}
+inline void Condition::signal() {
+    pthread_cond_signal(&mCond);
+}
+inline void Condition::broadcast() {
+    pthread_cond_broadcast(&mCond);
+}
+
+#endif // HAVE_PTHREADS
+
+// ---------------------------------------------------------------------------
+}; // namespace android
+// ---------------------------------------------------------------------------
+
+#endif // _LIBS_UTILS_CONDITON_H