Modify native ALooper to take an explicit ident.

The ALooper API now uses an explicit "identifier" for the integer
that is returned rather than implicitly using the fd.  This allows
the APIs that had the fd to be a little more sane.

Change-Id: I8507f535ad484c0bdc4a1bd016d87bb09acd7ff0
diff --git a/libs/gui/SensorEventQueue.cpp b/libs/gui/SensorEventQueue.cpp
index 3396f25..7eb6da5 100644
--- a/libs/gui/SensorEventQueue.cpp
+++ b/libs/gui/SensorEventQueue.cpp
@@ -86,7 +86,7 @@
     Mutex::Autolock _l(mLock);
     if (mPollLoop == 0) {
         mPollLoop = new PollLoop(true);
-        mPollLoop->setCallback(getFd(), POLLIN, NULL, NULL);
+        mPollLoop->setCallback(getFd(), getFd(), POLLIN, NULL, NULL);
     }
     return mPollLoop;
 }
diff --git a/libs/utils/PollLoop.cpp b/libs/utils/PollLoop.cpp
index f740fa0..6d3eeee 100644
--- a/libs/utils/PollLoop.cpp
+++ b/libs/utils/PollLoop.cpp
@@ -95,6 +95,7 @@
     RequestedCallback requestedCallback;
     requestedCallback.callback = NULL;
     requestedCallback.looperCallback = NULL;
+    requestedCallback.ident = 0;
     requestedCallback.data = NULL;
     mRequestedCallbacks.insertAt(requestedCallback, 0);
 }
@@ -116,7 +117,7 @@
         mPendingFdsPos++;
         if (outEvents != NULL) *outEvents = pending.events;
         if (outData != NULL) *outData = pending.data;
-        return pending.fd;
+        return pending.ident;
     }
     
     mLock.lock();
@@ -182,6 +183,7 @@
             const RequestedCallback& requestedCallback = mRequestedCallbacks.itemAt(i);
             PendingCallback pending;
             pending.fd = requestedFd.fd;
+            pending.ident = requestedCallback.ident;
             pending.events = revents;
             pending.callback = requestedCallback.callback;
             pending.looperCallback = requestedCallback.looperCallback;
@@ -191,7 +193,7 @@
                 mPendingCallbacks.push(pending);
             } else if (pending.fd != mWakeReadPipeFd) {
                 if (result == POLL_CALLBACK) {
-                    result = pending.fd;
+                    result = pending.ident;
                     if (outEvents != NULL) *outEvents = pending.events;
                     if (outData != NULL) *outData = pending.data;
                 } else {
@@ -268,16 +270,20 @@
     return mAllowNonCallbacks;
 }
 
+void PollLoop::setCallback(int fd, int ident, int events, Callback callback, void* data) {
+    setCallbackCommon(fd, ident, events, callback, NULL, data);
+}
+
 void PollLoop::setCallback(int fd, int events, Callback callback, void* data) {
-    setCallbackCommon(fd, events, callback, NULL, data);
+    setCallbackCommon(fd, POLL_CALLBACK, events, callback, NULL, data);
 }
 
-void PollLoop::setLooperCallback(int fd, int events, ALooper_callbackFunc* callback,
+void PollLoop::setLooperCallback(int fd, int ident, int events, ALooper_callbackFunc* callback,
         void* data) {
-    setCallbackCommon(fd, events, NULL, callback, data);
+    setCallbackCommon(fd, ident, events, NULL, callback, data);
 }
 
-void PollLoop::setCallbackCommon(int fd, int events, Callback callback,
+void PollLoop::setCallbackCommon(int fd, int ident, int events, Callback callback,
         ALooper_callbackFunc* looperCallback, void* data) {
 
 #if DEBUG_CALLBACKS
@@ -305,6 +311,7 @@
     RequestedCallback requestedCallback;
     requestedCallback.callback = callback;
     requestedCallback.looperCallback = looperCallback;
+    requestedCallback.ident = ident;
     requestedCallback.data = data;
 
     ssize_t index = getRequestIndexLocked(fd);