am 41c10433: Fix MulticastLock API to match WifiLock API. (0cbdb399) · Commits · e / os / android_frameworks_base

api/current.xml

+13 −0

Original line number	Diff line number	Diff line
		@@ -84317,6 +84317,19 @@
		visibility="public"
		>
		</method>
		<method name="setReferenceCounted"
		return="void"
		abstract="false"
		native="false"
		synchronized="false"
		static="false"
		final="false"
		deprecated="not deprecated"
		visibility="public"
		>
		<parameter name="refCounted" type="boolean">
		</parameter>
		</method>
		</class>
		<class name="WifiManager.WifiLock"
		extends="java.lang.Object"

wifi/java/android/net/wifi/WifiManager.java

+66 −12

Original line number	Diff line number	Diff line
		@@ -871,7 +871,10 @@ public class WifiManager {
		* Create a new MulticastLock
		*
		* @param tag a tag for the MulticastLock to identify it in debugging
		* messages.
		* messages. This string is never shown to the user under
		* normal conditions, but should be descriptive enough to
		* identify your application and the specific MulticastLock
		* within it, if it holds multiple MulticastLocks.
		*
		* @return a new, unacquired MulticastLock with the given tag.
		*
		@@ -887,26 +890,36 @@ public class WifiManager {
		* addressed to this device. Acquring a MulticastLock will
		* cause the stack to receive packets addressed to multicast
		* addresses. Processing these extra packets can cause a noticable
		* battery drain and should be disabled when not needed
		* battery drain and should be disabled when not needed.
		*/
		public class MulticastLock {
		private String mTag;
		private final IBinder mBinder;
		private int mRefCount;
		private boolean mRefCounted;
		private boolean mHeld;

		private MulticastLock(String tag) {
		mTag = tag;
		mBinder = new Binder();
		mRefCount = 0;
		mRefCounted = true;
		mHeld = false;
		}

		/**
		* Locks Wifi Multicast on until {@link #release} is called.
		*
		* The first call to {@code acquire} will lock the Multicast on
		* but subsequent calls will be ignored. Only one call to
		* {@link #release} will be required, regardless of the number of
		* times that {@code acquire} is called.
		* If this MulticastLock is reference-counted each call to
		* {@code acquire} will increment the reference count, and the
		* wifi interface will receive multicast packets as long as the
		* reference count is above zero.
		*
		* If this MulticastLock is not reference-counted, the first call to
		* {@code acquire} will turn on the multicast packets, but subsequent
		* calls will be ignored. Only one call to {@link #release} will
		* be required, regardless of the number of times that {@code acquire}
		* is called.
		*
		* Note that other applications may also lock Wifi Multicast on.
		* Only they can relinquish their lock.
		@@ -916,7 +929,7 @@ public class WifiManager {
		*/
		public void acquire() {
		synchronized (mBinder) {
		if (!mHeld) {
		if (mRefCounted ? (++mRefCount > 0) : (!mHeld)) {
		try {
		mService.acquireMulticastLock(mBinder, mTag);
		synchronized (WifiManager.this) {
		@@ -927,9 +940,9 @@ public class WifiManager {
		}
		mActiveLockCount++;
		}
		mHeld = true;
		} catch (RemoteException ignore) {
		}
		mHeld = true;
		}
		}
		}
		@@ -938,6 +951,18 @@ public class WifiManager {
		* Unlocks Wifi Multicast, restoring the filter of packets
		* not addressed specifically to this device and saving power.
		*
		* If this MulticastLock is reference-counted, each call to
		* {@code release} will decrement the reference count, and the
		* multicast packets will only stop being received when the reference
		* count reaches zero. If the reference count goes below zero (that
		* is, if {@code release} is called a greater number of times than
		* {@link #acquire}), an exception is thrown.
		*
		* If this MulticastLock is not reference-counted, the first call to
		* {@code release} (after the radio was multicast locked using
		* {@linke #acquire}) will unlock the multicast, and subsequent calls
		* will be ignored.
		*
		* Note that if any other Wifi Multicast Locks are still outstanding
		* this {@code release} call will not have an immediate effect. Only
		* when all applications have released all their Multicast Locks will
		@@ -948,19 +973,42 @@ public class WifiManager {
		*/
		public void release() {
		synchronized (mBinder) {
		if (mHeld) {
		if (mRefCounted ? (--mRefCount == 0) : (mHeld)) {
		try {
		mService.releaseMulticastLock();
		synchronized (WifiManager.this) {
		mActiveLockCount--;
		}
		mHeld = false;
		} catch (RemoteException ignore) {
		}
		mHeld = false;
		}
		if (mRefCount < 0) {
		throw new RuntimeException("MulticastLock under-locked "
		+ mTag);
		}
		}
		}

		/**
		* Controls whether this is a reference-counted or non-reference-
		* counted MulticastLock.
		*
		* Reference-counted MulticastLocks keep track of the number of calls
		* to {@link #acquire} and {@link #release}, and only stop the
		* reception of multicast packets when every call to {@link #acquire}
		* has been balanced with a call to {@link #release}. Non-reference-
		* counted MulticastLocks allow the reception of multicast packets
		* whenever {@link #acquire} is called and stop accepting multicast
		* packets whenever {@link #release} is called.
		*
		* @param refCounted true if this MulticastLock should keep a reference
		* count
		*/
		public void setReferenceCounted(boolean refCounted) {
		mRefCounted = refCounted;
		}

		/**
		* Checks whether this MulticastLock is currently held.
		*
		@@ -973,17 +1021,23 @@ public class WifiManager {
		}

		public String toString() {
		String s1, s2;
		String s1, s2, s3;
		synchronized (mBinder) {
		s1 = Integer.toHexString(System.identityHashCode(this));
		s2 = mHeld ? "held; " : "";
		return "MulticastLock{ " + s1 + "; " + s2 + " }";
		if (mRefCounted) {
		s3 = "refcounted: refcount = " + mRefCount;
		} else {
		s3 = "not refcounted";
		}
		return "MulticastLock{ " + s1 + "; " + s2 + s3 + " }";
		}
		}

		@Override
		protected void finalize() throws Throwable {
		super.finalize();
		setReferenceCounted(false);
		release();
		}
		}