am 49159f07: am 74bf59b4: Merge "Add new glue code for writing native apps." into gingerbread
Merge commit '49159f0748c704e53a7bd754f26113d9ab844a97'
* commit '49159f0748c704e53a7bd754f26113d9ab844a97':
Add new glue code for writing native apps.
diff --git a/core/jni/android_os_MessageQueue.cpp b/core/jni/android_os_MessageQueue.cpp
index 961f806..847b5a5 100644
--- a/core/jni/android_os_MessageQueue.cpp
+++ b/core/jni/android_os_MessageQueue.cpp
@@ -53,7 +53,7 @@
NativeMessageQueue::NativeMessageQueue() {
mPollLoop = PollLoop::getForThread();
if (mPollLoop == NULL) {
- mPollLoop = new PollLoop();
+ mPollLoop = new PollLoop(false);
PollLoop::setForThread(mPollLoop);
}
}
@@ -62,7 +62,7 @@
}
bool NativeMessageQueue::pollOnce(int timeoutMillis) {
- return mPollLoop->pollOnce(timeoutMillis);
+ return mPollLoop->pollOnce(timeoutMillis) != PollLoop::POLL_TIMEOUT;
}
void NativeMessageQueue::wake() {
diff --git a/include/utils/PollLoop.h b/include/utils/PollLoop.h
index b3651ca..81230e8 100644
--- a/include/utils/PollLoop.h
+++ b/include/utils/PollLoop.h
@@ -42,7 +42,7 @@
virtual ~PollLoop();
public:
- PollLoop();
+ PollLoop(bool allowNonCallbacks);
/**
* A callback that it to be invoked when an event occurs on a file descriptor.
@@ -54,6 +54,12 @@
*/
typedef bool (*Callback)(int fd, int events, void* data);
+ enum {
+ POLL_CALLBACK = ALOOPER_POLL_CALLBACK,
+ POLL_TIMEOUT = ALOOPER_POLL_TIMEOUT,
+ POLL_ERROR = ALOOPER_POLL_ERROR,
+ };
+
/**
* Performs a single call to poll() with optional timeout in milliseconds.
* Invokes callbacks for all file descriptors on which an event occurred.
@@ -61,16 +67,25 @@
* If the timeout is zero, returns immediately without blocking.
* If the timeout is negative, waits indefinitely until awoken.
*
- * Returns true if a callback was invoked or if the loop was awoken by wake().
- * Returns false if a timeout or error occurred.
+ * Returns ALOOPER_POLL_CALLBACK if a callback was invoked.
*
- * This method must only be called on the main thread.
+ * Returns ALOOPER_POLL_TIMEOUT if there was no data before the given
+ * timeout expired.
+ *
+ * Returns ALOPER_POLL_ERROR if an error occurred.
+ *
+ * Returns a value >= 0 containing a file descriptor if it has data
+ * and it has no callback function (requiring the caller here to handle it).
+ * In this (and only this) case outEvents and outData will contain the poll
+ * events and data associated with the fd.
+ *
+ * This method must only be called on the thread owning the PollLoop.
* This method blocks until either a file descriptor is signalled, a timeout occurs,
* or wake() is called.
* This method does not return until it has finished invoking the appropriate callbacks
* for all file descriptors that were signalled.
*/
- bool pollOnce(int timeoutMillis);
+ int32_t pollOnce(int timeoutMillis, int* outEvents = NULL, void** outData = NULL);
/**
* Wakes the loop asynchronously.
@@ -81,6 +96,12 @@
void wake();
/**
+ * Control whether this PollLoop instance allows using IDs instead
+ * of callbacks.
+ */
+ bool getAllowNonCallbacks() const;
+
+ /**
* Sets the callback for a file descriptor, replacing the existing one, if any.
* It is an error to call this method with events == 0 or callback == NULL.
*
@@ -95,7 +116,8 @@
/**
* Like setCallback(), but for the NDK callback function.
*/
- void setLooperCallback(int fd, int events, ALooper_callbackFunc* callback, void* data);
+ void setLooperCallback(int fd, int events, ALooper_callbackFunc* callback,
+ void* data);
/**
* Removes the callback for a file descriptor, if one exists.
@@ -141,7 +163,9 @@
ALooper_callbackFunc* looperCallback;
void* data;
};
-
+
+ const bool mAllowNonCallbacks;
+
Mutex mLock;
bool mPolling;
uint32_t mWaiters;
@@ -155,7 +179,9 @@
Vector<RequestedCallback> mRequestedCallbacks;
Vector<PendingCallback> mPendingCallbacks; // used privately by pollOnce
-
+ Vector<PendingCallback> mPendingFds; // used privately by pollOnce
+ size_t mPendingFdsPos;
+
void openWakePipe();
void closeWakePipe();
diff --git a/libs/ui/InputDispatcher.cpp b/libs/ui/InputDispatcher.cpp
index 42a7fc6..f809cba 100644
--- a/libs/ui/InputDispatcher.cpp
+++ b/libs/ui/InputDispatcher.cpp
@@ -54,7 +54,7 @@
InputDispatcher::InputDispatcher(const sp<InputDispatcherPolicyInterface>& policy) :
mPolicy(policy) {
- mPollLoop = new PollLoop();
+ mPollLoop = new PollLoop(false);
mInboundQueue.head.refCount = -1;
mInboundQueue.head.type = EventEntry::TYPE_SENTINEL;
diff --git a/libs/utils/PollLoop.cpp b/libs/utils/PollLoop.cpp
index 58fe141..f740fa0 100644
--- a/libs/utils/PollLoop.cpp
+++ b/libs/utils/PollLoop.cpp
@@ -25,8 +25,9 @@
static bool gHaveTLS = false;
static pthread_key_t gTLS = 0;
-PollLoop::PollLoop() :
- mPolling(false), mWaiters(0) {
+PollLoop::PollLoop(bool allowNonCallbacks) :
+ mAllowNonCallbacks(allowNonCallbacks), mPolling(false),
+ mWaiters(0), mPendingFdsPos(0) {
openWakePipe();
}
@@ -106,7 +107,18 @@
// method is currently only called by the destructor.
}
-bool PollLoop::pollOnce(int timeoutMillis) {
+int32_t PollLoop::pollOnce(int timeoutMillis, int* outEvents, void** outData) {
+ // If there are still pending fds from the last call, dispatch those
+ // first, to avoid an earlier fd from starving later ones.
+ const size_t pendingFdsCount = mPendingFds.size();
+ if (mPendingFdsPos < pendingFdsCount) {
+ const PendingCallback& pending = mPendingFds.itemAt(mPendingFdsPos);
+ mPendingFdsPos++;
+ if (outEvents != NULL) *outEvents = pending.events;
+ if (outData != NULL) *outData = pending.data;
+ return pending.fd;
+ }
+
mLock.lock();
while (mWaiters != 0) {
mResume.wait(mLock);
@@ -114,7 +126,7 @@
mPolling = true;
mLock.unlock();
- bool result;
+ int32_t result;
size_t requestedCount = mRequestedFds.size();
#if DEBUG_POLL_AND_WAKE
@@ -131,7 +143,7 @@
#if DEBUG_POLL_AND_WAKE
LOGD("%p ~ pollOnce - timeout", this);
#endif
- result = false;
+ result = POLL_TIMEOUT;
goto Done;
}
@@ -143,7 +155,7 @@
if (errno != EINTR) {
LOGW("Poll failed with an unexpected error, errno=%d", errno);
}
- result = false;
+ result = POLL_ERROR;
goto Done;
}
@@ -156,38 +168,44 @@
#endif
mPendingCallbacks.clear();
+ mPendingFds.clear();
+ mPendingFdsPos = 0;
+ if (outEvents != NULL) *outEvents = 0;
+ if (outData != NULL) *outData = NULL;
+
+ result = POLL_CALLBACK;
for (size_t i = 0; i < requestedCount; i++) {
const struct pollfd& requestedFd = mRequestedFds.itemAt(i);
short revents = requestedFd.revents;
if (revents) {
const RequestedCallback& requestedCallback = mRequestedCallbacks.itemAt(i);
- Callback callback = requestedCallback.callback;
- ALooper_callbackFunc* looperCallback = requestedCallback.looperCallback;
+ PendingCallback pending;
+ pending.fd = requestedFd.fd;
+ pending.events = revents;
+ pending.callback = requestedCallback.callback;
+ pending.looperCallback = requestedCallback.looperCallback;
+ pending.data = requestedCallback.data;
- if (callback || looperCallback) {
- PendingCallback pendingCallback;
- pendingCallback.fd = requestedFd.fd;
- pendingCallback.events = requestedFd.revents;
- pendingCallback.callback = callback;
- pendingCallback.looperCallback = looperCallback;
- pendingCallback.data = requestedCallback.data;
- mPendingCallbacks.push(pendingCallback);
- } else {
- if (requestedFd.fd == mWakeReadPipeFd) {
-#if DEBUG_POLL_AND_WAKE
- LOGD("%p ~ pollOnce - awoken", this);
-#endif
- char buffer[16];
- ssize_t nRead;
- do {
- nRead = read(mWakeReadPipeFd, buffer, sizeof(buffer));
- } while (nRead == sizeof(buffer));
+ if (pending.callback || pending.looperCallback) {
+ mPendingCallbacks.push(pending);
+ } else if (pending.fd != mWakeReadPipeFd) {
+ if (result == POLL_CALLBACK) {
+ result = pending.fd;
+ if (outEvents != NULL) *outEvents = pending.events;
+ if (outData != NULL) *outData = pending.data;
} else {
-#if DEBUG_POLL_AND_WAKE || DEBUG_CALLBACKS
- LOGD("%p ~ pollOnce - fd %d has no callback!", this, requestedFd.fd);
-#endif
+ mPendingFds.push(pending);
}
+ } else {
+#if DEBUG_POLL_AND_WAKE
+ LOGD("%p ~ pollOnce - awoken", this);
+#endif
+ char buffer[16];
+ ssize_t nRead;
+ do {
+ nRead = read(mWakeReadPipeFd, buffer, sizeof(buffer));
+ } while (nRead == sizeof(buffer));
}
respondedCount -= 1;
@@ -196,7 +214,6 @@
}
}
}
- result = true;
Done:
mLock.lock();
@@ -206,7 +223,7 @@
}
mLock.unlock();
- if (result) {
+ if (result == POLL_CALLBACK || result >= 0) {
size_t pendingCount = mPendingCallbacks.size();
for (size_t i = 0; i < pendingCount; i++) {
const PendingCallback& pendingCallback = mPendingCallbacks.itemAt(i);
@@ -247,6 +264,10 @@
}
}
+bool PollLoop::getAllowNonCallbacks() const {
+ return mAllowNonCallbacks;
+}
+
void PollLoop::setCallback(int fd, int events, Callback callback, void* data) {
setCallbackCommon(fd, events, callback, NULL, data);
}
@@ -263,12 +284,18 @@
LOGD("%p ~ setCallback - fd=%d, events=%d", this, fd, events);
#endif
- if (! events || (! callback && ! looperCallback)) {
- LOGE("Invalid attempt to set a callback with no selected poll events or no callback.");
+ if (! events) {
+ LOGE("Invalid attempt to set a callback with no selected poll events.");
removeCallback(fd);
return;
}
+ if (! callback && ! looperCallback && ! mAllowNonCallbacks) {
+ LOGE("Invalid attempt to set NULL callback but not allowed.");
+ removeCallback(fd);
+ return;
+ }
+
wakeAndLock();
struct pollfd requestedFd;
diff --git a/libs/utils/tests/PollLoop_test.cpp b/libs/utils/tests/PollLoop_test.cpp
index 4848c0f..02f1808 100644
--- a/libs/utils/tests/PollLoop_test.cpp
+++ b/libs/utils/tests/PollLoop_test.cpp
@@ -87,7 +87,7 @@
sp<PollLoop> mPollLoop;
virtual void SetUp() {
- mPollLoop = new PollLoop();
+ mPollLoop = new PollLoop(false);
}
virtual void TearDown() {
@@ -98,26 +98,26 @@
TEST_F(PollLoopTest, PollOnce_WhenNonZeroTimeoutAndNotAwoken_WaitsForTimeoutAndReturnsFalse) {
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(100);
+ int32_t result = mPollLoop->pollOnce(100);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal timeout";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
}
TEST_F(PollLoopTest, PollOnce_WhenNonZeroTimeoutAndAwokenBeforeWaiting_ImmediatelyReturnsTrue) {
mPollLoop->wake();
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(1000);
+ int32_t result = mPollLoop->pollOnce(1000);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. zero because wake() was called before waiting";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because loop was awoken";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because loop was awoken";
}
TEST_F(PollLoopTest, PollOnce_WhenNonZeroTimeoutAndAwokenWhileWaiting_PromptlyReturnsTrue) {
@@ -125,24 +125,24 @@
delayedWake->run();
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(1000);
+ int32_t result = mPollLoop->pollOnce(1000);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal wake delay";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because loop was awoken";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because loop was awoken";
}
TEST_F(PollLoopTest, PollOnce_WhenZeroTimeoutAndNoRegisteredFDs_ImmediatelyReturnsFalse) {
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(0);
+ int32_t result = mPollLoop->pollOnce(0);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should be approx. zero";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
}
TEST_F(PollLoopTest, PollOnce_WhenZeroTimeoutAndNoSignalledFDs_ImmediatelyReturnsFalse) {
@@ -152,13 +152,13 @@
handler.setCallback(mPollLoop, pipe.receiveFd, POLL_IN);
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(0);
+ int32_t result = mPollLoop->pollOnce(0);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should be approx. zero";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
EXPECT_EQ(0, handler.callbackCount)
<< "callback should not have been invoked because FD was not signalled";
}
@@ -171,13 +171,13 @@
handler.setCallback(mPollLoop, pipe.receiveFd, POLL_IN);
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(0);
+ int32_t result = mPollLoop->pollOnce(0);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should be approx. zero";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because FD was signalled";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because FD was signalled";
EXPECT_EQ(1, handler.callbackCount)
<< "callback should be invoked exactly once";
EXPECT_EQ(pipe.receiveFd, handler.fd)
@@ -193,13 +193,13 @@
handler.setCallback(mPollLoop, pipe.receiveFd, POLL_IN);
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(100);
+ int32_t result = mPollLoop->pollOnce(100);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal timeout";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
EXPECT_EQ(0, handler.callbackCount)
<< "callback should not have been invoked because FD was not signalled";
}
@@ -212,15 +212,15 @@
handler.setCallback(mPollLoop, pipe.receiveFd, POLL_IN);
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(100);
+ int32_t result = mPollLoop->pollOnce(100);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
ASSERT_EQ(OK, pipe.readSignal())
<< "signal should actually have been written";
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should be approx. zero";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because FD was signalled";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because FD was signalled";
EXPECT_EQ(1, handler.callbackCount)
<< "callback should be invoked exactly once";
EXPECT_EQ(pipe.receiveFd, handler.fd)
@@ -238,15 +238,15 @@
delayedWriteSignal->run();
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(1000);
+ int32_t result = mPollLoop->pollOnce(1000);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
ASSERT_EQ(OK, pipe.readSignal())
<< "signal should actually have been written";
EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal signal delay";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because FD was signalled";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because FD was signalled";
EXPECT_EQ(1, handler.callbackCount)
<< "callback should be invoked exactly once";
EXPECT_EQ(pipe.receiveFd, handler.fd)
@@ -264,15 +264,15 @@
mPollLoop->removeCallback(pipe.receiveFd);
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(100);
+ int32_t result = mPollLoop->pollOnce(100);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
ASSERT_EQ(OK, pipe.readSignal())
<< "signal should actually have been written";
EXPECT_NEAR(100, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal timeout because FD was no longer registered";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
EXPECT_EQ(0, handler.callbackCount)
<< "callback should not be invoked";
}
@@ -287,15 +287,15 @@
pipe.writeSignal();
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(0);
+ int32_t result = mPollLoop->pollOnce(0);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
ASSERT_EQ(OK, pipe.readSignal())
<< "signal should actually have been written";
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal zero because FD was already signalled";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because FD was signalled";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because FD was signalled";
EXPECT_EQ(1, handler.callbackCount)
<< "callback should be invoked";
@@ -310,8 +310,8 @@
<< "signal should actually have been written";
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. equal zero because timeout was zero";
- EXPECT_FALSE(result)
- << "pollOnce result should be false because timeout occurred";
+ EXPECT_EQ(result, PollLoop::POLL_TIMEOUT)
+ << "pollOnce result should be POLL_TIMEOUT";
EXPECT_EQ(1, handler.callbackCount)
<< "callback should not be invoked this time";
}
@@ -351,15 +351,15 @@
pipe.writeSignal(); // would cause FD to be considered signalled
StopWatch stopWatch("pollOnce");
- bool result = mPollLoop->pollOnce(100);
+ int32_t result = mPollLoop->pollOnce(100);
int32_t elapsedMillis = ns2ms(stopWatch.elapsedTime());
ASSERT_EQ(OK, pipe.readSignal())
<< "signal should actually have been written";
EXPECT_NEAR(0, elapsedMillis, TIMING_TOLERANCE_MS)
<< "elapsed time should approx. zero because FD was already signalled";
- EXPECT_TRUE(result)
- << "pollOnce result should be true because FD was signalled";
+ EXPECT_EQ(result, PollLoop::POLL_CALLBACK)
+ << "pollOnce result should be POLL_CALLBACK because FD was signalled";
EXPECT_EQ(0, handler1.callbackCount)
<< "original handler callback should not be invoked because it was replaced";
EXPECT_EQ(1, handler2.callbackCount)
diff --git a/native/android/input.cpp b/native/android/input.cpp
index 015a1ce..89d53e2 100644
--- a/native/android/input.cpp
+++ b/native/android/input.cpp
@@ -186,9 +186,9 @@
}
void AInputQueue_attachLooper(AInputQueue* queue, ALooper* looper,
- ALooper_callbackFunc callback, void* data) {
+ ALooper_callbackFunc* callback, void* data) {
queue->setPollLoop(static_cast<android::PollLoop*>(looper));
- ALooper_setCallback(looper, queue->getConsumer().getChannel()->getReceivePipeFd(),
+ ALooper_addFd(looper, queue->getConsumer().getChannel()->getReceivePipeFd(),
POLLIN, callback, data);
}
diff --git a/native/android/looper.cpp b/native/android/looper.cpp
index 6e78bbd..1564c47 100644
--- a/native/android/looper.cpp
+++ b/native/android/looper.cpp
@@ -27,22 +27,41 @@
return PollLoop::getForThread().get();
}
-ALooper* ALooper_prepare() {
+ALooper* ALooper_prepare(int32_t opts) {
+ bool allowFds = (opts&ALOOPER_PREPARE_ALLOW_NON_CALLBACKS) != 0;
sp<PollLoop> loop = PollLoop::getForThread();
if (loop == NULL) {
- loop = new PollLoop();
+ loop = new PollLoop(allowFds);
PollLoop::setForThread(loop);
}
+ if (loop->getAllowNonCallbacks() != allowFds) {
+ LOGW("ALooper_prepare again with different ALOOPER_PREPARE_ALLOW_NON_CALLBACKS");
+ }
return loop.get();
}
-int32_t ALooper_pollOnce(int timeoutMillis) {
+int32_t ALooper_pollOnce(int timeoutMillis, int* outEvents, void** outData) {
sp<PollLoop> loop = PollLoop::getForThread();
if (loop == NULL) {
LOGW("ALooper_pollOnce: No looper for this thread!");
return -1;
}
- return loop->pollOnce(timeoutMillis) ? 1 : 0;
+ return loop->pollOnce(timeoutMillis, outEvents, outData);
+}
+
+int32_t ALooper_pollAll(int timeoutMillis, int* outEvents, void** outData) {
+ sp<PollLoop> loop = PollLoop::getForThread();
+ if (loop == NULL) {
+ LOGW("ALooper_pollOnce: No looper for this thread!");
+ return -1;
+ }
+
+ int32_t result;
+ while ((result = loop->pollOnce(timeoutMillis, outEvents, outData)) == ALOOPER_POLL_CALLBACK) {
+ ;
+ }
+
+ return result;
}
void ALooper_acquire(ALooper* looper) {
@@ -53,11 +72,11 @@
static_cast<PollLoop*>(looper)->decStrong((void*)ALooper_acquire);
}
-void ALooper_setCallback(ALooper* looper, int fd, int events,
+void ALooper_addFd(ALooper* looper, int fd, int events,
ALooper_callbackFunc* callback, void* data) {
static_cast<PollLoop*>(looper)->setLooperCallback(fd, events, callback, data);
}
-int32_t ALooper_removeCallback(ALooper* looper, int fd) {
+int32_t ALooper_removeFd(ALooper* looper, int fd) {
return static_cast<PollLoop*>(looper)->removeCallback(fd) ? 1 : 0;
}
diff --git a/native/glue/threaded_app/Android.mk b/native/glue/threaded_app/Android.mk
new file mode 100644
index 0000000..cfc9b2a
--- /dev/null
+++ b/native/glue/threaded_app/Android.mk
@@ -0,0 +1,18 @@
+BASE_PATH := $(call my-dir)
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+
+# our source files
+#
+LOCAL_SRC_FILES:= \
+ threaded_app.c
+
+LOCAL_C_INCLUDES += \
+ frameworks/base/native/include \
+ frameworks/base/core/jni/android \
+ dalvik/libnativehelper/include/nativehelper
+
+LOCAL_MODULE:= libthreaded_app
+
+include $(BUILD_STATIC_LIBRARY)
diff --git a/native/glue/threaded_app/threaded_app.c b/native/glue/threaded_app/threaded_app.c
new file mode 100644
index 0000000..c9cae8b
--- /dev/null
+++ b/native/glue/threaded_app/threaded_app.c
@@ -0,0 +1,275 @@
+/*
+ * Copyright (C) 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.
+ *
+ */
+
+#include <jni.h>
+
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/resource.h>
+
+#include <android_glue/threaded_app.h>
+
+#include <android/log.h>
+
+#define LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO, "threaded_app", __VA_ARGS__))
+#define LOGW(...) ((void)__android_log_print(ANDROID_LOG_WARN, "threaded_app", __VA_ARGS__))
+
+void android_app_destroy(struct android_app* android_app) {
+ LOGI("android_app_destroy!");
+ pthread_mutex_lock(&android_app->mutex);
+ if (android_app->inputQueue != NULL) {
+ AInputQueue_detachLooper(android_app->inputQueue);
+ }
+ android_app->destroyed = 1;
+ pthread_cond_broadcast(&android_app->cond);
+ pthread_mutex_unlock(&android_app->mutex);
+ // Can't touch android_app object after this.
+}
+
+int8_t android_app_read_cmd(struct android_app* android_app) {
+ int8_t cmd;
+ if (read(android_app->msgread, &cmd, sizeof(cmd)) == sizeof(cmd)) {
+ return cmd;
+ } else {
+ LOGW("No data on command pipe!");
+ }
+ return -1;
+}
+
+void android_app_exec_cmd(struct android_app* android_app, int8_t cmd) {
+ switch (cmd) {
+ case APP_CMD_INPUT_CHANGED:
+ LOGI("APP_CMD_INPUT_CHANGED\n");
+ pthread_mutex_lock(&android_app->mutex);
+ if (android_app->inputQueue != NULL) {
+ AInputQueue_detachLooper(android_app->inputQueue);
+ }
+ android_app->inputQueue = android_app->pendingInputQueue;
+ if (android_app->inputQueue != NULL) {
+ LOGI("Attaching input queue to looper");
+ AInputQueue_attachLooper(android_app->inputQueue,
+ android_app->looper, NULL, (void*)LOOPER_ID_EVENT);
+ }
+ pthread_cond_broadcast(&android_app->cond);
+ pthread_mutex_unlock(&android_app->mutex);
+ break;
+
+ case APP_CMD_WINDOW_CHANGED:
+ LOGI("APP_CMD_WINDOW_CHANGED\n");
+ pthread_mutex_lock(&android_app->mutex);
+ android_app->window = android_app->pendingWindow;
+ pthread_cond_broadcast(&android_app->cond);
+ pthread_mutex_unlock(&android_app->mutex);
+ break;
+
+ case APP_CMD_START:
+ case APP_CMD_RESUME:
+ case APP_CMD_PAUSE:
+ case APP_CMD_STOP:
+ LOGI("activityState=%d\n", cmd);
+ pthread_mutex_lock(&android_app->mutex);
+ android_app->activityState = cmd;
+ pthread_cond_broadcast(&android_app->cond);
+ pthread_mutex_unlock(&android_app->mutex);
+ break;
+
+ case APP_CMD_DESTROY:
+ LOGI("APP_CMD_DESTROY\n");
+ android_app->destroyRequested = 1;
+ break;
+ }
+}
+
+static void* android_app_entry(void* param) {
+ struct android_app* android_app = (struct android_app*)param;
+
+ ALooper* looper = ALooper_prepare(ALOOPER_PREPARE_ALLOW_NON_CALLBACKS);
+ ALooper_addFd(looper, android_app->msgread, POLLIN, NULL, (void*)LOOPER_ID_MAIN);
+ android_app->looper = looper;
+
+ pthread_mutex_lock(&android_app->mutex);
+ android_app->running = 1;
+ pthread_cond_broadcast(&android_app->cond);
+ pthread_mutex_unlock(&android_app->mutex);
+
+ android_main(android_app);
+ return NULL;
+}
+
+// --------------------------------------------------------------------
+// Native activity interaction (called from main thread)
+// --------------------------------------------------------------------
+
+static struct android_app* android_app_create(ANativeActivity* activity) {
+ struct android_app* android_app = (struct android_app*)malloc(sizeof(struct android_app));
+ memset(android_app, 0, sizeof(struct android_app));
+ android_app->activity = activity;
+
+ pthread_mutex_init(&android_app->mutex, NULL);
+ pthread_cond_init(&android_app->cond, NULL);
+
+ int msgpipe[2];
+ if (pipe(msgpipe)) {
+ LOGI("could not create pipe: %s", strerror(errno));
+ }
+ android_app->msgread = msgpipe[0];
+ android_app->msgwrite = msgpipe[1];
+
+ pthread_attr_t attr;
+ pthread_attr_init(&attr);
+ pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
+ pthread_create(&android_app->thread, &attr, android_app_entry, android_app);
+
+ // Wait for thread to start.
+ pthread_mutex_lock(&android_app->mutex);
+ while (!android_app->running) {
+ pthread_cond_wait(&android_app->cond, &android_app->mutex);
+ }
+ pthread_mutex_unlock(&android_app->mutex);
+
+ return android_app;
+}
+
+static void android_app_write_cmd(struct android_app* android_app, int8_t cmd) {
+ if (write(android_app->msgwrite, &cmd, sizeof(cmd)) != sizeof(cmd)) {
+ LOGI("Failure writing android_app cmd: %s\n", strerror(errno));
+ }
+}
+
+static void android_app_set_input(struct android_app* android_app, AInputQueue* inputQueue) {
+ pthread_mutex_lock(&android_app->mutex);
+ android_app->pendingInputQueue = inputQueue;
+ android_app_write_cmd(android_app, APP_CMD_INPUT_CHANGED);
+ while (android_app->inputQueue != android_app->pendingInputQueue) {
+ pthread_cond_wait(&android_app->cond, &android_app->mutex);
+ }
+ pthread_mutex_unlock(&android_app->mutex);
+}
+
+static void android_app_set_window(struct android_app* android_app, ANativeWindow* window) {
+ pthread_mutex_lock(&android_app->mutex);
+ android_app->pendingWindow = window;
+ android_app_write_cmd(android_app, APP_CMD_WINDOW_CHANGED);
+ while (android_app->window != android_app->pendingWindow) {
+ pthread_cond_wait(&android_app->cond, &android_app->mutex);
+ }
+ pthread_mutex_unlock(&android_app->mutex);
+}
+
+static void android_app_set_activity_state(struct android_app* android_app, int8_t cmd) {
+ pthread_mutex_lock(&android_app->mutex);
+ android_app_write_cmd(android_app, cmd);
+ while (android_app->activityState != cmd) {
+ pthread_cond_wait(&android_app->cond, &android_app->mutex);
+ }
+ pthread_mutex_unlock(&android_app->mutex);
+}
+
+static void android_app_free(struct android_app* android_app) {
+ pthread_mutex_lock(&android_app->mutex);
+ android_app_write_cmd(android_app, APP_CMD_DESTROY);
+ while (!android_app->destroyed) {
+ pthread_cond_wait(&android_app->cond, &android_app->mutex);
+ }
+ pthread_mutex_unlock(&android_app->mutex);
+
+ close(android_app->msgread);
+ close(android_app->msgwrite);
+ pthread_cond_destroy(&android_app->cond);
+ pthread_mutex_destroy(&android_app->mutex);
+ free(android_app);
+}
+
+static void onDestroy(ANativeActivity* activity) {
+ LOGI("Destroy: %p\n", activity);
+ android_app_free((struct android_app*)activity->instance);
+}
+
+static void onStart(ANativeActivity* activity) {
+ LOGI("Start: %p\n", activity);
+ android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_START);
+}
+
+static void onResume(ANativeActivity* activity) {
+ LOGI("Resume: %p\n", activity);
+ android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_RESUME);
+}
+
+static void* onSaveInstanceState(ANativeActivity* activity, size_t* outLen) {
+ LOGI("SaveInstanceState: %p\n", activity);
+ return NULL;
+}
+
+static void onPause(ANativeActivity* activity) {
+ LOGI("Pause: %p\n", activity);
+ android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_PAUSE);
+}
+
+static void onStop(ANativeActivity* activity) {
+ LOGI("Stop: %p\n", activity);
+ android_app_set_activity_state((struct android_app*)activity->instance, APP_CMD_STOP);
+}
+
+static void onLowMemory(ANativeActivity* activity) {
+ LOGI("LowMemory: %p\n", activity);
+}
+
+static void onWindowFocusChanged(ANativeActivity* activity, int focused) {
+ LOGI("WindowFocusChanged: %p -- %d\n", activity, focused);
+ android_app_write_cmd((struct android_app*)activity->instance,
+ focused ? APP_CMD_GAINED_FOCUS : APP_CMD_LOST_FOCUS);
+}
+
+static void onNativeWindowCreated(ANativeActivity* activity, ANativeWindow* window) {
+ LOGI("NativeWindowCreated: %p -- %p\n", activity, window);
+ android_app_set_window((struct android_app*)activity->instance, window);
+}
+
+static void onNativeWindowDestroyed(ANativeActivity* activity, ANativeWindow* window) {
+ LOGI("NativeWindowDestroyed: %p -- %p\n", activity, window);
+ android_app_set_window((struct android_app*)activity->instance, NULL);
+}
+
+static void onInputQueueCreated(ANativeActivity* activity, AInputQueue* queue) {
+ LOGI("InputQueueCreated: %p -- %p\n", activity, queue);
+ android_app_set_input((struct android_app*)activity->instance, queue);
+}
+
+static void onInputQueueDestroyed(ANativeActivity* activity, AInputQueue* queue) {
+ LOGI("InputQueueDestroyed: %p -- %p\n", activity, queue);
+ android_app_set_input((struct android_app*)activity->instance, NULL);
+}
+
+void ANativeActivity_onCreate(ANativeActivity* activity,
+ void* savedState, size_t savedStateSize) {
+ LOGI("Creating: %p\n", activity);
+ activity->callbacks->onDestroy = onDestroy;
+ activity->callbacks->onStart = onStart;
+ activity->callbacks->onResume = onResume;
+ activity->callbacks->onSaveInstanceState = onSaveInstanceState;
+ activity->callbacks->onPause = onPause;
+ activity->callbacks->onStop = onStop;
+ activity->callbacks->onLowMemory = onLowMemory;
+ activity->callbacks->onWindowFocusChanged = onWindowFocusChanged;
+ activity->callbacks->onNativeWindowCreated = onNativeWindowCreated;
+ activity->callbacks->onNativeWindowDestroyed = onNativeWindowDestroyed;
+ activity->callbacks->onInputQueueCreated = onInputQueueCreated;
+ activity->callbacks->onInputQueueDestroyed = onInputQueueDestroyed;
+
+ activity->instance = android_app_create(activity);
+}
diff --git a/native/include/android/input.h b/native/include/android/input.h
index 75be85a..014b6a3 100644
--- a/native/include/android/input.h
+++ b/native/include/android/input.h
@@ -534,10 +534,11 @@
typedef struct AInputQueue AInputQueue;
/*
- * Add this input queue to a looper for processing.
+ * Add this input queue to a looper for processing. See
+ * ALooper_addFd() for information on the callback and data params.
*/
void AInputQueue_attachLooper(AInputQueue* queue, ALooper* looper,
- ALooper_callbackFunc callback, void* data);
+ ALooper_callbackFunc* callback, void* data);
/*
* Remove the input queue from the looper it is currently attached to.
diff --git a/native/include/android/looper.h b/native/include/android/looper.h
index 90a8983..2917216 100644
--- a/native/include/android/looper.h
+++ b/native/include/android/looper.h
@@ -24,25 +24,151 @@
extern "C" {
#endif
+/**
+ * ALooper
+ *
+ * A looper is the state tracking an event loop for a thread.
+ * Loopers do not define event structures or other such things; rather
+ * they are a lower-level facility to attach one or more discrete objects
+ * listening for an event. An "event" here is simply data available on
+ * a file descriptor: each attached object has an associated file descriptor,
+ * and waiting for "events" means (internally) polling on all of these file
+ * descriptors until one or more of them have data available.
+ *
+ * A thread can have only one ALooper associated with it.
+ */
struct ALooper;
typedef struct ALooper ALooper;
+/**
+ * For callback-based event loops, this is the prototype of the function
+ * that is called. It is given the file descriptor it is associated with,
+ * a bitmask of the poll events that were triggered (typically POLLIN), and
+ * the data pointer that was originally supplied.
+ *
+ * Implementations should return 1 to continue receiving callbacks, or 0
+ * to have this file descriptor and callback unregistered from the looper.
+ */
typedef int ALooper_callbackFunc(int fd, int events, void* data);
+/**
+ * Return the ALooper associated with the calling thread, or NULL if
+ * there is not one.
+ */
ALooper* ALooper_forThread();
-ALooper* ALooper_prepare();
+enum {
+ /**
+ * Option for ALooper_prepare: this ALooper will accept calls to
+ * ALooper_addFd() that do not have a callback (that is provide NULL
+ * for the callback). In this case the caller of ALooper_pollOnce()
+ * or ALooper_pollAll() MUST check the return from these functions to
+ * discover when data is available on such fds and process it.
+ */
+ ALOOPER_PREPARE_ALLOW_NON_CALLBACKS = 1<<0
+};
-int32_t ALooper_pollOnce(int timeoutMillis);
+/**
+ * Prepare an ALooper associated with the calling thread, and return it.
+ * If the thread already has an ALooper, it is returned. Otherwise, a new
+ * one is created, associated with the thread, and returned.
+ *
+ * The opts may be ALOOPER_PREPARE_ALLOW_NON_CALLBACKS or 0.
+ */
+ALooper* ALooper_prepare(int32_t opts);
+enum {
+ /**
+ * Result from ALooper_pollOnce() and ALooper_pollAll(): one or
+ * more callbacks were executed.
+ */
+ ALOOPER_POLL_CALLBACK = -1,
+
+ /**
+ * Result from ALooper_pollOnce() and ALooper_pollAll(): the
+ * timeout expired.
+ */
+ ALOOPER_POLL_TIMEOUT = -2,
+
+ /**
+ * Result from ALooper_pollOnce() and ALooper_pollAll(): an error
+ * occurred.
+ */
+ ALOOPER_POLL_ERROR = -3,
+};
+
+/**
+ * Wait for events to be available, with optional timeout in milliseconds.
+ * Invokes callbacks for all file descriptors on which an event occurred.
+ *
+ * If the timeout is zero, returns immediately without blocking.
+ * If the timeout is negative, waits indefinitely until an event appears.
+ *
+ * Returns ALOOPER_POLL_CALLBACK if a callback was invoked.
+ *
+ * Returns ALOOPER_POLL_TIMEOUT if there was no data before the given
+ * timeout expired.
+ *
+ * Returns ALOPER_POLL_ERROR if an error occurred.
+ *
+ * Returns a value >= 0 containing a file descriptor if it has data
+ * and it has no callback function (requiring the caller here to handle it).
+ * In this (and only this) case outEvents and outData will contain the poll
+ * events and data associated with the fd.
+ *
+ * This method does not return until it has finished invoking the appropriate callbacks
+ * for all file descriptors that were signalled.
+ */
+int32_t ALooper_pollOnce(int timeoutMillis, int* outEvents, void** outData);
+
+/**
+ * Like ALooper_pollOnce(), but performs all pending callbacks until all
+ * data has been consumed or a file descriptor is available with no callback.
+ * This function will never return ALOOPER_POLL_CALLBACK.
+ */
+int32_t ALooper_pollAll(int timeoutMillis, int* outEvents, void** outData);
+
+/**
+ * Acquire a reference on the given ALooper object. This prevents the object
+ * from being deleted until the reference is removed. This is only needed
+ * to safely hand an ALooper from one thread to another.
+ */
void ALooper_acquire(ALooper* looper);
+/**
+ * Remove a reference that was previously acquired with ALooper_acquire().
+ */
void ALooper_release(ALooper* looper);
-void ALooper_setCallback(ALooper* looper, int fd, int events,
+/**
+ * Add a new file descriptor to be polled by the looper. If the same file
+ * descriptor was previously added, it is replaced.
+ *
+ * "fd" is the file descriptor to be added.
+ * "events" are the poll events to wake up on. Typically this is POLLIN.
+ * "callback" is the function to call when there is an event on the file
+ * descriptor.
+ * "id" is an identifier to associated with this file descriptor, or 0.
+ * "data" is a private data pointer to supply to the callback.
+ *
+ * There are two main uses of this function:
+ *
+ * (1) If "callback" is non-NULL, then
+ * this function will be called when there is data on the file descriptor. It
+ * should execute any events it has pending, appropriately reading from the
+ * file descriptor.
+ *
+ * (2) If "callback" is NULL, the fd will be returned by ALooper_pollOnce
+ * when it has data available, requiring the caller to take care of processing
+ * it.
+ */
+void ALooper_addFd(ALooper* looper, int fd, int events,
ALooper_callbackFunc* callback, void* data);
-int32_t ALooper_removeCallback(ALooper* looper, int fd);
+/**
+ * Remove a previously added file descriptor from the looper.
+ */
+int32_t ALooper_removeFd(ALooper* looper, int fd);
#ifdef __cplusplus
};
diff --git a/native/include/android_glue/threaded_app.h b/native/include/android_glue/threaded_app.h
new file mode 100644
index 0000000..80de3bf
--- /dev/null
+++ b/native/include/android_glue/threaded_app.h
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 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.
+ *
+ */
+
+#include <poll.h>
+#include <pthread.h>
+#include <sched.h>
+
+#include <android/native_activity.h>
+#include <android/looper.h>
+
+/**
+ * This is the interface for the standard glue code of a threaded
+ * application. In this model, the application's code is running
+ * in its own thread separate from the main thread of the process.
+ * It is not required that this thread be associated with the Java
+ * VM, although it will need to be in order to make JNI calls any
+ * Java objects.
+ */
+struct android_app {
+ // The application can place a pointer to its own state object
+ // here if it likes.
+ void* userData;
+
+ // The ANativeActivity object instance that this app is running in.
+ ANativeActivity* activity;
+
+ // The ALooper associated with the app's thread.
+ ALooper* looper;
+
+ // When non-NULL, this is the input queue from which the app will
+ // receive user input events.
+ AInputQueue* inputQueue;
+
+ // When non-NULL, this is the window surface that the app can draw in.
+ ANativeWindow* window;
+
+ // Current state of the app's activity. May be either APP_CMD_START,
+ // APP_CMD_RESUME, APP_CMD_PAUSE, or APP_CMD_STOP; see below.
+ int activityState;
+
+ // This is non-zero when the application's NativeActivity is being
+ // destroyed and waiting for the app thread to complete.
+ int destroyRequested;
+
+ // -------------------------------------------------
+ // Below are "private" implementation of the glue code.
+
+ pthread_mutex_t mutex;
+ pthread_cond_t cond;
+
+ int msgread;
+ int msgwrite;
+
+ pthread_t thread;
+
+ int running;
+ int destroyed;
+ AInputQueue* pendingInputQueue;
+ ANativeWindow* pendingWindow;
+};
+
+enum {
+ /**
+ * Looper data ID of commands coming from the app's main thread.
+ * These can be retrieved and processed with android_app_read_cmd()
+ * and android_app_exec_cmd().
+ */
+ LOOPER_ID_MAIN = 1,
+
+ /**
+ * Looper data ID of events coming from the AInputQueue of the
+ * application's window. These can be read via the inputQueue
+ * object of android_app.
+ */
+ LOOPER_ID_EVENT = 2
+};
+
+enum {
+ /**
+ * Command from main thread: the AInputQueue has changed. Upon processing
+ * this command, android_app->inputQueue will be updated to the new queue
+ * (or NULL).
+ */
+ APP_CMD_INPUT_CHANGED,
+
+ /**
+ * Command from main thread: the ANativeWindow has changed. Upon processing
+ * this command, android_app->window will be updated to the new window surface
+ * (or NULL).
+ */
+ APP_CMD_WINDOW_CHANGED,
+
+ /**
+ * Command from main thread: the app's activity window has gained
+ * input focus.
+ */
+ APP_CMD_GAINED_FOCUS,
+
+ /**
+ * Command from main thread: the app's activity window has lost
+ * input focus.
+ */
+ APP_CMD_LOST_FOCUS,
+
+ /**
+ * Command from main thread: the app's activity has been started.
+ */
+ APP_CMD_START,
+
+ /**
+ * Command from main thread: the app's activity has been resumed.
+ */
+ APP_CMD_RESUME,
+
+ /**
+ * Command from main thread: the app's activity has been paused.
+ */
+ APP_CMD_PAUSE,
+
+ /**
+ * Command from main thread: the app's activity has been stopped.
+ */
+ APP_CMD_STOP,
+
+ /**
+ * Command from main thread: the app's activity is being destroyed,
+ * and waiting for the app thread to clean up and exit before proceeding.
+ */
+ APP_CMD_DESTROY,
+};
+
+/**
+ * Call if android_app->destroyRequested is non-zero. Upon return, the
+ * android_app structure is no longer valid and must not be touched.
+ */
+void android_app_destroy(struct android_app* android_app);
+
+/**
+ * Call when ALooper_pollAll() returns LOOPER_ID_MAIN, reading the next
+ * app command message.
+ */
+int8_t android_app_read_cmd(struct android_app* android_app);
+
+/**
+ * Call with the command returned by android_app_read_cmd() to do the
+ * default processing of the given command.
+ */
+void android_app_exec_cmd(struct android_app* android_app, int8_t cmd);
+
+/**
+ * This is the function that application code must implement, representing
+ * the main entry to the app.
+ */
+extern void android_main(struct android_app* app);