Media server death nodification

1 files changed, 111 insertions, 0 deletions

diff --git a/media/libmedia/IMediaDeathNotifier.cpp b/media/libmedia/IMediaDeathNotifier.cpp
new file mode 100644
index 0000000..39ac076
--- /dev/null
+++ b/media/libmedia/IMediaDeathNotifier.cpp
@@ -0,0 +1,111 @@
+/*
+** Copyright 2010, 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.
+*/
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "IMediaDeathNotifier"
+#include <utils/Log.h>
+
+#include <binder/IServiceManager.h>
+#include <binder/IPCThreadState.h>
+#include <media/IMediaDeathNotifier.h>
+
+namespace android {
+
+// client singleton for binder interface to services
+Mutex IMediaDeathNotifier::sServiceLock;
+sp<IMediaPlayerService> IMediaDeathNotifier::sMediaPlayerService;
+sp<IMediaDeathNotifier::DeathNotifier> IMediaDeathNotifier::sDeathNotifier;
+SortedVector< wp<IMediaDeathNotifier> > IMediaDeathNotifier::sObitRecipients;
+
+// establish binder interface to MediaPlayerService
+/*static*/const sp<IMediaPlayerService>&
+IMediaDeathNotifier::getMediaPlayerService()
+{
+    LOGV("getMediaPlayerService");
+    Mutex::Autolock _l(sServiceLock);
+    if (sMediaPlayerService.get() == 0) {
+        sp<IServiceManager> sm = defaultServiceManager();
+        sp<IBinder> binder;
+        do {
+            binder = sm->getService(String16("media.player"));
+            if (binder != 0) {
+                break;
+             }
+             LOGW("Media player service not published, waiting...");
+             usleep(500000); // 0.5 s
+        } while(true);
+
+        if (sDeathNotifier == NULL) {
+        sDeathNotifier = new DeathNotifier();
+    }
+    binder->linkToDeath(sDeathNotifier);
+    sMediaPlayerService = interface_cast<IMediaPlayerService>(binder);
+    }
+    LOGE_IF(sMediaPlayerService == 0, "no media player service!?");
+    return sMediaPlayerService;
+}
+
+/*static*/ void
+IMediaDeathNotifier::addObitRecipient(const wp<IMediaDeathNotifier>& recipient)
+{
+    LOGV("addObitRecipient");
+    Mutex::Autolock _l(sServiceLock);
+    sObitRecipients.add(recipient);
+}
+
+/*static*/ void
+IMediaDeathNotifier::removeObitRecipient(const wp<IMediaDeathNotifier>& recipient)
+{
+    LOGV("removeObitRecipient");
+    Mutex::Autolock _l(sServiceLock);
+    sObitRecipients.remove(recipient);
+}
+
+void
+IMediaDeathNotifier::DeathNotifier::binderDied(const wp<IBinder>& who) {
+    LOGW("media server died");
+
+    // Need to do this with the lock held
+    SortedVector< wp<IMediaDeathNotifier> > list;
+    {
+        Mutex::Autolock _l(sServiceLock);
+        sMediaPlayerService.clear();
+        list = sObitRecipients;
+    }
+
+    // Notify application when media server dies.
+    // Don't hold the static lock during callback in case app
+    // makes a call that needs the lock.
+    size_t count = list.size();
+    for (size_t iter = 0; iter < count; ++iter) {
+        sp<IMediaDeathNotifier> notifier = list[iter].promote();
+        if (notifier != 0) {
+            notifier->died();
+        }
+    }
+}
+
+IMediaDeathNotifier::DeathNotifier::~DeathNotifier()
+{
+    LOGV("DeathNotifier::~DeathNotifier");
+    Mutex::Autolock _l(sServiceLock);
+    sObitRecipients.clear();
+    if (sMediaPlayerService != 0) {
+        sMediaPlayerService->asBinder()->unlinkToDeath(this);
+    }
+}
+
+}; // namespace android