Revert "Binder linkage no longer depends on JNI objrefs as persistent tokens" (e2ed9562) · Commits · e / os / android_frameworks_base

core/jni/android_util_Binder.cpp

+51 −145

Original line number	Diff line number	Diff line
		@@ -31,8 +31,6 @@
		#include <binder/IPCThreadState.h>
		#include <utils/Log.h>
		#include <utils/SystemClock.h>
		#include <utils/List.h>
		#include <utils/KeyedVector.h>
		#include <cutils/logger.h>
		#include <binder/Parcel.h>
		#include <binder/ProcessState.h>
		@@ -324,15 +322,25 @@ private:
		class JavaBBinderHolder : public RefBase
		{
		public:
		sp<JavaBBinder> get(JNIEnv* env, jobject obj)
		JavaBBinderHolder(JNIEnv* env, jobject object)
		: mObject(object)
		{
		LOGV("Creating JavaBBinderHolder for Object %p\n", object);
		}
		~JavaBBinderHolder()
		{
		LOGV("Destroying JavaBBinderHolder for Object %p\n", mObject);
		}

		sp<JavaBBinder> get(JNIEnv* env)
		{
		AutoMutex _l(mLock);
		sp<JavaBBinder> b = mBinder.promote();
		if (b == NULL) {
		b = new JavaBBinder(env, obj);
		b = new JavaBBinder(env, mObject);
		mBinder = b;
		LOGV("Creating JavaBinder %p (refs %p) for Object %p, weakCount=%d\n",
		b.get(), b->getWeakRefs(), obj, b->getWeakRefs()->getWeakCount());
		b.get(), b->getWeakRefs(), mObject, b->getWeakRefs()->getWeakCount());
		}

		return b;
		@@ -346,41 +354,20 @@ public:

		private:
		Mutex mLock;
		jobject mObject;
		wp<JavaBBinder> mBinder;
		};

		// ----------------------------------------------------------------------------

		// Per-IBinder death recipient bookkeeping. This is how we reconcile local jobject
		// death recipient references passed in through JNI with the permanent corresponding
		// JavaDeathRecipient objects.

		class JavaDeathRecipient;

		class DeathRecipientList : public RefBase {
		List< sp<JavaDeathRecipient> > mList;
		Mutex mLock;

		public:
		~DeathRecipientList();

		void add(const sp<JavaDeathRecipient>& recipient);
		void remove(const sp<JavaDeathRecipient>& recipient);
		sp<JavaDeathRecipient> find(jobject recipient);
		};

		// ----------------------------------------------------------------------------

		class JavaDeathRecipient : public IBinder::DeathRecipient
		{
		public:
		JavaDeathRecipient(JNIEnv* env, jobject object, sp<DeathRecipientList>& list)
		: mVM(jnienv_to_javavm(env)), mObject(env->NewGlobalRef(object)), mList(list)
		JavaDeathRecipient(JNIEnv* env, jobject object)
		: mVM(jnienv_to_javavm(env)), mObject(env->NewGlobalRef(object)),
		mHoldsRef(true)
		{
		// These objects manage their own lifetimes so are responsible for final bookkeeping.
		// The list holds a strong reference to this object.
		mList->add(this);

		incStrong(this);
		android_atomic_inc(&gNumDeathRefs);
		incRefsCreated(env);
		}
		@@ -404,12 +391,16 @@ public:

		void clearReference()
		{
		mList->remove(this);
		bool release = false;
		mLock.lock();
		if (mHoldsRef) {
		mHoldsRef = false;
		release = true;
		}
		mLock.unlock();
		if (release) {
		decStrong(this);
		}

		bool matches(jobject obj) {
		JNIEnv* env = javavm_to_jnienv(mVM);
		return env->IsSameObject(obj, mObject);
		}

		protected:
		@@ -424,57 +415,12 @@ protected:
		private:
		JavaVM* const mVM;
		jobject const mObject;
		sp<DeathRecipientList> mList;
		Mutex mLock;
		bool mHoldsRef;
		};

		// ----------------------------------------------------------------------------

		DeathRecipientList::~DeathRecipientList() {
		AutoMutex _l(mLock);

		// Should never happen -- the JavaDeathRecipient objects that have added themselves
		// to the list are holding references on the list object. Only when they are torn
		// down can the list header be destroyed.
		if (mList.size() > 0) {
		LOGE("Retiring binder %p with extant death recipients\n", this);
		}
		}

		void DeathRecipientList::add(const sp<JavaDeathRecipient>& recipient) {
		AutoMutex _l(mLock);

		mList.push_back(recipient);
		}

		void DeathRecipientList::remove(const sp<JavaDeathRecipient>& recipient) {
		AutoMutex _l(mLock);

		List< sp<JavaDeathRecipient> >::iterator iter;
		for (iter = mList.begin(); iter != mList.end(); iter++) {
		if (*iter == recipient) {
		mList.erase(iter);
		return;
		}
		}
		}

		sp<JavaDeathRecipient> DeathRecipientList::find(jobject recipient) {
		AutoMutex _l(mLock);

		List< sp<JavaDeathRecipient> >::iterator iter;
		for (iter = mList.begin(); iter != mList.end(); iter++) {
		if ((*iter)->matches(recipient)) {
		return *iter;
		}
		}
		return NULL;
		}

		static KeyedVector<IBinder*, sp<DeathRecipientList> > gDeathRecipientsByIBinder;
		static Mutex gDeathRecipientMapLock;

		// ----------------------------------------------------------------------------

		namespace android {

		static void proxy_cleanup(const void* id, void* obj, void* cleanupCookie)
		@@ -544,7 +490,7 @@ sp<IBinder> ibinderForJavaObject(JNIEnv* env, jobject obj)
		if (env->IsInstanceOf(obj, gBinderOffsets.mClass)) {
		JavaBBinderHolder* jbh = (JavaBBinderHolder*)
		env->GetIntField(obj, gBinderOffsets.mObject);
		return jbh != NULL ? jbh->get(env, obj) : NULL;
		return jbh != NULL ? jbh->get(env) : NULL;
		}

		if (env->IsInstanceOf(obj, gBinderProxyOffsets.mClass)) {
		@@ -675,26 +621,26 @@ static void android_os_Binder_flushPendingCommands(JNIEnv* env, jobject clazz)
		IPCThreadState::self()->flushCommands();
		}

		static void android_os_Binder_init(JNIEnv* env, jobject obj)
		static void android_os_Binder_init(JNIEnv* env, jobject clazz)
		{
		JavaBBinderHolder* jbh = new JavaBBinderHolder();
		JavaBBinderHolder* jbh = new JavaBBinderHolder(env, clazz);
		if (jbh == NULL) {
		jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
		return;
		}
		LOGV("Java Binder %p: acquiring first ref on holder %p", obj, jbh);
		jbh->incStrong((void*)android_os_Binder_init);
		env->SetIntField(obj, gBinderOffsets.mObject, (int)jbh);
		LOGV("Java Binder %p: acquiring first ref on holder %p", clazz, jbh);
		jbh->incStrong(clazz);
		env->SetIntField(clazz, gBinderOffsets.mObject, (int)jbh);
		}

		static void android_os_Binder_destroy(JNIEnv* env, jobject obj)
		static void android_os_Binder_destroy(JNIEnv* env, jobject clazz)
		{
		JavaBBinderHolder* jbh = (JavaBBinderHolder*)
		env->GetIntField(obj, gBinderOffsets.mObject);
		env->GetIntField(clazz, gBinderOffsets.mObject);
		if (jbh != NULL) {
		env->SetIntField(obj, gBinderOffsets.mObject, 0);
		LOGV("Java Binder %p: removing ref on holder %p", obj, jbh);
		jbh->decStrong((void*)android_os_Binder_init);
		env->SetIntField(clazz, gBinderOffsets.mObject, 0);
		LOGV("Java Binder %p: removing ref on holder %p", clazz, jbh);
		jbh->decStrong(clazz);
		} else {
		// Encountering an uninitialized binder is harmless. All it means is that
		// the Binder was only partially initialized when its finalizer ran and called
		@@ -702,7 +648,7 @@ static void android_os_Binder_destroy(JNIEnv* env, jobject obj)
		// For example, a Binder subclass constructor might have thrown an exception before
		// it could delegate to its superclass's constructor. Consequently init() would
		// not have been called and the holder pointer would remain NULL.
		LOGV("Java Binder %p: ignoring uninitialized binder", obj);
		LOGV("Java Binder %p: ignoring uninitialized binder", clazz);
		}
		}

		@@ -1027,25 +973,8 @@ static void android_os_BinderProxy_linkToDeath(JNIEnv* env, jobject obj,
		LOGV("linkToDeath: binder=%p recipient=%p\n", target, recipient);

		if (!target->localBinder()) {
		sp<JavaDeathRecipient> jdr;

		{
		sp<DeathRecipientList> list;
		AutoMutex _maplocker(gDeathRecipientMapLock);

		ssize_t listIndex = gDeathRecipientsByIBinder.indexOfKey(target);
		if (listIndex < 0) {
		// Set up the death notice bookkeeping for this binder lazily
		list = new DeathRecipientList;
		gDeathRecipientsByIBinder.add(target, list);
		} else {
		list = gDeathRecipientsByIBinder.valueAt(listIndex);
		}

		jdr = new JavaDeathRecipient(env, recipient, list);
		}

		status_t err = target->linkToDeath(jdr, NULL, flags);
		sp<JavaDeathRecipient> jdr = new JavaDeathRecipient(env, recipient);
		status_t err = target->linkToDeath(jdr, recipient, flags);
		if (err != NO_ERROR) {
		// Failure adding the death recipient, so clear its reference
		// now.
		@@ -1074,20 +1003,8 @@ static jboolean android_os_BinderProxy_unlinkToDeath(JNIEnv* env, jobject obj,
		LOGV("unlinkToDeath: binder=%p recipient=%p\n", target, recipient);

		if (!target->localBinder()) {
		status_t err = NAME_NOT_FOUND;
		sp<JavaDeathRecipient> origJDR;
		{
		AutoMutex _maplocker(gDeathRecipientMapLock);
		ssize_t listIndex = gDeathRecipientsByIBinder.indexOfKey(target);
		if (listIndex >= 0) {
		sp<DeathRecipientList> list = gDeathRecipientsByIBinder.valueAt(listIndex);
		origJDR = list->find(recipient);
		}
		}
		// If we found the matching recipient, proceed to unlink using that
		if (origJDR != NULL) {
		wp<IBinder::DeathRecipient> dr;
		err = target->unlinkToDeath(origJDR, NULL, flags, &dr);
		status_t err = target->unlinkToDeath(NULL, recipient, flags, &dr);
		if (err == NO_ERROR && dr != NULL) {
		sp<IBinder::DeathRecipient> sdr = dr.promote();
		JavaDeathRecipient* jdr = static_cast<JavaDeathRecipient*>(sdr.get());
		@@ -1095,8 +1012,6 @@ static jboolean android_os_BinderProxy_unlinkToDeath(JNIEnv* env, jobject obj,
		jdr->clearReference();
		}
		}
		}

		if (err == NO_ERROR \|\| err == DEAD_OBJECT) {
		res = JNI_TRUE;
		} else {
		@@ -1116,15 +1031,6 @@ static void android_os_BinderProxy_destroy(JNIEnv* env, jobject obj)
		env->SetIntField(obj, gBinderProxyOffsets.mObject, 0);
		b->decStrong(obj);
		IPCThreadState::self()->flushCommands();

		// tear down the death recipient bookkeeping
		{
		AutoMutex _maplocker(gDeathRecipientMapLock);
		ssize_t listIndex = gDeathRecipientsByIBinder.indexOfKey(b);
		if (listIndex >= 0) {
		gDeathRecipientsByIBinder.removeItemsAt((size_t)listIndex);
		}
		}
		}

		// ----------------------------------------------------------------------------

include/binder/IBinder.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -98,7 +98,7 @@ public:
		* Register the @a recipient for a notification if this binder
		* goes away. If this binder object unexpectedly goes away
		* (typically because its hosting process has been killed),
		* then DeathRecipient::binderDied() will be called with a reference
		* then DeathRecipient::binderDied() will be called with a referene
		* to this.
		*
		* The @a cookie is optional -- if non-NULL, it should be a