CKKSListenerCollection.m   [plain text]

#if OCTAGON

#import "keychain/ckks/CKKSListenerCollection.h"
#import "keychain/ot/ObjCImprovements.h"

@interface CKKSListenerCollection ()
@property NSString* name;
@property NSMapTable<dispatch_queue_t, id>* listeners;
@end

@implementation CKKSListenerCollection

- (instancetype)initWithName:(NSString*)name
{
if((self = [super init])) {
_name = name;
// Backwards from how we'd like, but it's the best way to have weak pointers to ListenerTypes.
_listeners = [NSMapTable strongToWeakObjectsMapTable];
}
return self;
}

- (NSString*)description
{
@synchronized(self.listeners) {
return [NSString stringWithFormat:@"<CKKSListenerCollection(%@): %@>", self.name, [[self.listeners objectEnumerator] allObjects]];
}
}

- (void)registerListener:(id)listener
{
@synchronized(self.listeners) {
bool alreadyRegisteredListener = false;
NSEnumerator *enumerator = [self.listeners objectEnumerator];
id value;

while ((value = [enumerator nextObject])) {
// actually use pointer comparison
alreadyRegisteredListener |= (value == listener);
}

if(listener && !alreadyRegisteredListener) {
NSString* queueName = [NSString stringWithFormat: @"%@-%@", self.name, listener];

dispatch_queue_t objQueue = dispatch_queue_create([queueName UTF8String], DISPATCH_QUEUE_SERIAL_WITH_AUTORELEASE_POOL);
[self.listeners setObject: listener forKey: objQueue];
}
}
}

- (void)iterateListeners:(void (^)(id))block
{
@synchronized(self.listeners) {
NSEnumerator *enumerator = [self.listeners keyEnumerator];
dispatch_queue_t dq;

// Queue up the changes for each listener.
while ((dq = [enumerator nextObject])) {
id listener = [self.listeners objectForKey: dq];
WEAKIFY(listener);

if(listener) {
dispatch_async(dq, ^{
STRONGIFY(listener);
block(listener);
});
}
}
}
}

@end

#endif // OCTAGON