Polish comments and correct concurrent writeable behavior
diff --git a/src/objective-c/RxLibrary/GRXBufferedPipe.h b/src/objective-c/RxLibrary/GRXBufferedPipe.h
index a871ea8..ae08cc3 100644
--- a/src/objective-c/RxLibrary/GRXBufferedPipe.h
+++ b/src/objective-c/RxLibrary/GRXBufferedPipe.h
@@ -36,8 +36,7 @@
* crash. If you want to react to flow control signals to prevent that, instead of using this class
* you can implement an object that conforms to GRXWriter.
*
- * Thread-safety:
- * The methods of an object of this class should not be called concurrently from different threads.
+ * Thread-safety: the methods of this class are thread-safe.
*/
@interface GRXBufferedPipe : GRXWriter<GRXWriteable>
diff --git a/src/objective-c/RxLibrary/GRXConcurrentWriteable.h b/src/objective-c/RxLibrary/GRXConcurrentWriteable.h
index 606f5de..55468b3 100644
--- a/src/objective-c/RxLibrary/GRXConcurrentWriteable.h
+++ b/src/objective-c/RxLibrary/GRXConcurrentWriteable.h
@@ -43,21 +43,22 @@
- (instancetype)initWithWriteable:(id<GRXWriteable>)writeable;
/**
- * Enqueues writeValue: to be sent to the writeable in the main thread.
- * The passed handler is invoked from the main thread after writeValue: returns.
+ * Enqueues writeValue: to be sent to the writeable from the designated dispatch queue.
+ * The passed handler is invoked from designated dispatch queue after writeValue: returns.
*/
- (void)enqueueValue:(id)value completionHandler:(void (^)(void))handler;
/**
- * Enqueues writesFinishedWithError:nil to be sent to the writeable in the main thread. After that
- * message is sent to the writeable, all other methods of this object are effectively noops.
+ * Enqueues writesFinishedWithError:nil to be sent to the writeable in the designated dispatch
+ * queue. After that message is sent to the writeable, all other methods of this object are
+ * effectively noops.
*/
- (void)enqueueSuccessfulCompletion;
/**
* If the writeable has not yet received a writesFinishedWithError: message, this will enqueue one
- * to be sent to it in the main thread, and cancel all other pending messages to the writeable
- * enqueued by this object (both past and future).
+ * to be sent to it in the designated dispatch queue, and cancel all other pending messages to the
+ * writeable enqueued by this object (both past and future).
* The error argument cannot be nil.
*/
- (void)cancelWithError:(NSError *)error;
diff --git a/src/objective-c/RxLibrary/GRXConcurrentWriteable.m b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
index 229d592..d9d0e8c 100644
--- a/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
+++ b/src/objective-c/RxLibrary/GRXConcurrentWriteable.m
@@ -63,8 +63,10 @@
- (void)enqueueSuccessfulCompletion {
dispatch_async(_writeableQueue, ^{
- if (self->_alreadyFinished) {
- return;
+ @synchronized (self) {
+ if (self->_alreadyFinished) {
+ return;
+ }
}
[self.writeable writesFinishedWithError:nil];
// Skip any possible message to the wrapped writeable enqueued after this one.
@@ -74,10 +76,14 @@
- (void)cancelWithError:(NSError *)error {
NSAssert(error != nil, @"For a successful completion, use enqueueSuccessfulCompletion.");
- dispatch_async(_writeableQueue, ^{
+ @synchronized (self) {
if (self->_alreadyFinished) {
return;
}
+ }
+ dispatch_async(_writeableQueue, ^{
+ // If enqueueSuccessfulCompletion is already issued, self.writeable is nil and the following
+ // line is no-op.
[self.writeable writesFinishedWithError:error];
self.writeable = nil;
});
@@ -85,8 +91,10 @@
- (void)cancelSilently {
dispatch_async(_writeableQueue, ^{
- if (self->_alreadyFinished) {
- return;
+ @synchronized (self) {
+ if (self->_alreadyFinished) {
+ return;
+ }
}
self.writeable = nil;
});
diff --git a/src/objective-c/RxLibrary/GRXForwardingWriter.h b/src/objective-c/RxLibrary/GRXForwardingWriter.h
index 3814ff8..00366b6 100644
--- a/src/objective-c/RxLibrary/GRXForwardingWriter.h
+++ b/src/objective-c/RxLibrary/GRXForwardingWriter.h
@@ -25,11 +25,7 @@
* input writer, and for classes that represent objects with input and
* output sequences of values, like an RPC.
*
- * Thread-safety:
- * All messages sent to this object need to be serialized. When it is started, the writer it wraps
- * is started in the same thread. Manual state changes are propagated to the wrapped writer in the
- * same thread too. Importantly, all messages the wrapped writer sends to its writeable need to be
- * serialized with any message sent to this object.
+ * Thread-safety: the methods of this class are thread safe.
*/
@interface GRXForwardingWriter : GRXWriter
- (instancetype)initWithWriter:(GRXWriter *)writer NS_DESIGNATED_INITIALIZER;
diff --git a/src/objective-c/RxLibrary/GRXImmediateSingleWriter.h b/src/objective-c/RxLibrary/GRXImmediateSingleWriter.h
index 601abdc..2fa38b3 100644
--- a/src/objective-c/RxLibrary/GRXImmediateSingleWriter.h
+++ b/src/objective-c/RxLibrary/GRXImmediateSingleWriter.h
@@ -23,6 +23,8 @@
/**
* Utility to construct GRXWriter instances from values that are immediately available when
* required.
+ *
+ * Thread safety: the methods of this class are thread safe.
*/
@interface GRXImmediateSingleWriter : GRXImmediateWriter
