Upintegrate the common_time service from ics-aah.

Move the common_time service developed in the ics-aah branch back into
master.

The common_time service is a small service build to synchronize an
arbitrary timeline amongst peers on a local sub-net.  While running
and configured, the service will elect a master from the set of
available devices within the subnet, define a relationship between the
common_time timeline the local time timeline (provided by the local
time HAL), and then attempt to maintain synchronization between common
and local time by controlling the frequency of the local time clock
via the HAL, or by disciplining local time in the digital domain if
the local time HAL implementation does not support HW slewing.

On its own, the native common time service will do nothing until it is
configured.  The CommonTimeManagementService (running out of the
system server process) is responsible for implementing policy
regarding configuration and operation of the common_time service and
will be added in a subsequent CL.

Change-Id: I71292f9b9b1797665865689c4572c9d3a0552f64
Signed-off-by: John Grossman <johngro@google.com>

1 files changed, 129 insertions, 0 deletions

diff --git a/media/common_time/cc_helper.cpp b/media/common_time/cc_helper.cpp
new file mode 100644
index 0000000..8d8556c
--- /dev/null
+++ b/media/common_time/cc_helper.cpp
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2011 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.
+ */
+
+#include <stdint.h>
+
+#include <common_time/cc_helper.h>
+#include <common_time/ICommonClock.h>
+#include <utils/threads.h>
+
+namespace android {
+
+Mutex CCHelper::lock_;
+sp<ICommonClock> CCHelper::common_clock_;
+sp<ICommonClockListener> CCHelper::common_clock_listener_;
+uint32_t CCHelper::ref_count_ = 0;
+
+bool CCHelper::verifyClock_l() {
+    bool ret = false;
+
+    if (common_clock_ == NULL) {
+        common_clock_ = ICommonClock::getInstance();
+        if (common_clock_ == NULL)
+            goto bailout;
+    }
+
+    if (ref_count_ > 0) {
+        if (common_clock_listener_ == NULL) {
+            common_clock_listener_ = new CommonClockListener();
+            if (common_clock_listener_ == NULL)
+                goto bailout;
+
+            if (OK != common_clock_->registerListener(common_clock_listener_))
+                goto bailout;
+        }
+    }
+
+    ret = true;
+
+bailout:
+    if (!ret) {
+        common_clock_listener_ = NULL;
+        common_clock_ = NULL;
+    }
+    return ret;
+}
+
+CCHelper::CCHelper() {
+    Mutex::Autolock lock(&lock_);
+    ref_count_++;
+    verifyClock_l();
+}
+
+CCHelper::~CCHelper() {
+    Mutex::Autolock lock(&lock_);
+
+    assert(ref_count_ > 0);
+    ref_count_--;
+
+    // If we were the last CCHelper instance in the system, and we had
+    // previously register a listener, unregister it now so that the common time
+    // service has the chance to go into auto-disabled mode.
+    if (!ref_count_ &&
+       (common_clock_ != NULL) &&
+       (common_clock_listener_ != NULL)) {
+        common_clock_->unregisterListener(common_clock_listener_);
+        common_clock_listener_ = NULL;
+    }
+}
+
+void CCHelper::CommonClockListener::onTimelineChanged(uint64_t timelineID) {
+    // do nothing; listener is only really used as a token so the server can
+    // find out when clients die.
+}
+
+// Helper methods which attempts to make calls to the common time binder
+// service.  If the first attempt fails with DEAD_OBJECT, the helpers will
+// attempt to make a connection to the service again (assuming that the process
+// hosting the service had crashed and the client proxy we are holding is dead)
+// If the second attempt fails, or no connection can be made, the we let the
+// error propagate up the stack and let the caller deal with the situation as
+// best they can.
+#define CCHELPER_METHOD(decl, call)                 \
+    status_t CCHelper::decl {                       \
+        Mutex::Autolock lock(&lock_);               \
+                                                    \
+        if (!verifyClock_l())                       \
+            return DEAD_OBJECT;                     \
+                                                    \
+        status_t status = common_clock_->call;      \
+        if (DEAD_OBJECT == status) {                \
+            if (!verifyClock_l())                   \
+                return DEAD_OBJECT;                 \
+            status = common_clock_->call;           \
+        }                                           \
+                                                    \
+        return status;                              \
+    }
+
+#define VERIFY_CLOCK()
+
+CCHELPER_METHOD(isCommonTimeValid(bool* valid, uint32_t* timelineID),
+                isCommonTimeValid(valid, timelineID))
+CCHELPER_METHOD(commonTimeToLocalTime(int64_t commonTime, int64_t* localTime),
+                commonTimeToLocalTime(commonTime, localTime))
+CCHELPER_METHOD(localTimeToCommonTime(int64_t localTime, int64_t* commonTime),
+                localTimeToCommonTime(localTime, commonTime))
+CCHELPER_METHOD(getCommonTime(int64_t* commonTime),
+                getCommonTime(commonTime))
+CCHELPER_METHOD(getCommonFreq(uint64_t* freq),
+                getCommonFreq(freq))
+CCHELPER_METHOD(getLocalTime(int64_t* localTime),
+                getLocalTime(localTime))
+CCHELPER_METHOD(getLocalFreq(uint64_t* freq),
+                getLocalFreq(freq))
+
+}  // namespace android