Merge "Fix cancellation race problem for aysnc DNS API" am: de6217b8e2

am: 829e409827

Change-Id: I633a592c7f46162268a759f84a77211443e9a04e
This commit is contained in:
Luke Huang
2019-03-28 20:45:44 -07:00
committed by android-build-merger
2 changed files with 37 additions and 25 deletions

View File

@@ -205,6 +205,7 @@ public final class DnsResolver {
if (cancellationSignal != null && cancellationSignal.isCanceled()) {
return;
}
final Object lock = new Object();
final FileDescriptor queryfd;
try {
queryfd = resNetworkSend((network != null
@@ -214,8 +215,8 @@ public final class DnsResolver {
return;
}
maybeAddCancellationSignal(cancellationSignal, queryfd);
registerFDListener(executor, queryfd, callback);
maybeAddCancellationSignal(cancellationSignal, queryfd, lock);
registerFDListener(executor, queryfd, callback, cancellationSignal, lock);
}
/**
@@ -242,6 +243,7 @@ public final class DnsResolver {
if (cancellationSignal != null && cancellationSignal.isCanceled()) {
return;
}
final Object lock = new Object();
final FileDescriptor queryfd;
try {
queryfd = resNetworkQuery((network != null
@@ -251,31 +253,37 @@ public final class DnsResolver {
return;
}
maybeAddCancellationSignal(cancellationSignal, queryfd);
registerFDListener(executor, queryfd, callback);
maybeAddCancellationSignal(cancellationSignal, queryfd, lock);
registerFDListener(executor, queryfd, callback, cancellationSignal, lock);
}
private <T> void registerFDListener(@NonNull Executor executor,
@NonNull FileDescriptor queryfd, @NonNull AnswerCallback<T> answerCallback) {
@NonNull FileDescriptor queryfd, @NonNull AnswerCallback<T> answerCallback,
@Nullable CancellationSignal cancellationSignal, @NonNull Object lock) {
Looper.getMainLooper().getQueue().addOnFileDescriptorEventListener(
queryfd,
FD_EVENTS,
(fd, events) -> {
executor.execute(() -> {
byte[] answerbuf = null;
try {
answerbuf = resNetworkResult(fd);
} catch (ErrnoException e) {
Log.e(TAG, "resNetworkResult:" + e.toString());
answerCallback.onQueryException(e);
return;
}
synchronized (lock) {
if (cancellationSignal != null && cancellationSignal.isCanceled()) {
return;
}
byte[] answerbuf = null;
try {
answerbuf = resNetworkResult(fd);
} catch (ErrnoException e) {
Log.e(TAG, "resNetworkResult:" + e.toString());
answerCallback.onQueryException(e);
return;
}
try {
answerCallback.onAnswer(
answerCallback.parser.parse(answerbuf));
} catch (ParseException e) {
answerCallback.onParseException(e);
try {
answerCallback.onAnswer(
answerCallback.parser.parse(answerbuf));
} catch (ParseException e) {
answerCallback.onParseException(e);
}
}
});
// Unregister this fd listener
@@ -284,14 +292,16 @@ public final class DnsResolver {
}
private void maybeAddCancellationSignal(@Nullable CancellationSignal cancellationSignal,
@NonNull FileDescriptor queryfd) {
@NonNull FileDescriptor queryfd, @NonNull Object lock) {
if (cancellationSignal == null) return;
cancellationSignal.setOnCancelListener(
() -> {
Looper.getMainLooper().getQueue()
.removeOnFileDescriptorEventListener(queryfd);
resNetworkCancel(queryfd);
});
cancellationSignal.setOnCancelListener(() -> {
synchronized (lock) {
if (!queryfd.valid()) return;
Looper.getMainLooper().getQueue()
.removeOnFileDescriptorEventListener(queryfd);
resNetworkCancel(queryfd);
}
});
}
private static class DnsAddressAnswer extends DnsPacket {

View File

@@ -470,6 +470,7 @@ static jbyteArray android_net_utils_resNetworkResult(JNIEnv *env, jobject thiz,
std::vector<uint8_t> buf(MAXPACKETSIZE, 0);
int res = resNetworkResult(fd, &rcode, buf.data(), MAXPACKETSIZE);
jniSetFileDescriptorOfFD(env, javaFd, -1);
if (res < 0) {
throwErrnoException(env, "resNetworkResult", -res);
return nullptr;
@@ -490,6 +491,7 @@ static jbyteArray android_net_utils_resNetworkResult(JNIEnv *env, jobject thiz,
static void android_net_utils_resNetworkCancel(JNIEnv *env, jobject thiz, jobject javaFd) {
int fd = jniGetFDFromFileDescriptor(env, javaFd);
resNetworkCancel(fd);
jniSetFileDescriptorOfFD(env, javaFd, -1);
}
static jobject android_net_utils_getTcpRepairWindow(JNIEnv *env, jobject thiz, jobject javaFd) {