Merge commit '7621e2f8dec938cf48181c8b10afc9b01f444e68' into beta

Telegram/Watch/Extension/SSignalKit/SAtomic.m

@@ -0,0 +1,93 @@
+#import "SAtomic.h"
+
+#import <pthread.h>
+
+@interface SAtomic ()
+{
+    pthread_mutex_t _lock;
+    pthread_mutexattr_t _attr;
+    bool _isRecursive;
+    id _value;
+}
+
+@end
+
+@implementation SAtomic
+
+- (instancetype)initWithValue:(id)value
+{
+    self = [super init];
+    if (self != nil)
+    {
+        pthread_mutex_init(&_lock, NULL);
+        _value = value;
+    }
+    return self;
+}
+
+- (instancetype)initWithValue:(id)value recursive:(bool)recursive {
+    self = [super init];
+    if (self != nil)
+    {
+        _isRecursive = recursive;
+        
+        if (recursive) {
+            pthread_mutexattr_init(&_attr);
+            pthread_mutexattr_settype(&_attr, PTHREAD_MUTEX_RECURSIVE);
+            pthread_mutex_init(&_lock, &_attr);
+        } else {
+            pthread_mutex_init(&_lock, NULL);
+        }
+        
+        _value = value;
+    }
+    return self;
+}
+
+- (void)dealloc {
+    if (_isRecursive) {
+        pthread_mutexattr_destroy(&_attr);
+    }
+    pthread_mutex_destroy(&_lock);
+}
+
+- (id)swap:(id)newValue
+{
+    id previousValue = nil;
+    pthread_mutex_lock(&_lock);
+    previousValue = _value;
+    _value = newValue;
+    pthread_mutex_unlock(&_lock);
+    return previousValue;
+}
+
+- (id)value
+{
+    id previousValue = nil;
+    pthread_mutex_lock(&_lock);
+    previousValue = _value;
+    pthread_mutex_unlock(&_lock);
+    
+    return previousValue;
+}
+
+- (id)modify:(id (^)(id))f
+{
+    id newValue = nil;
+    pthread_mutex_lock(&_lock);
+    newValue = f(_value);
+    _value = newValue;
+    pthread_mutex_unlock(&_lock);
+    return newValue;
+}
+
+- (id)with:(id (^)(id))f
+{
+    id result = nil;
+    pthread_mutex_lock(&_lock);
+    result = f(_value);
+    pthread_mutex_unlock(&_lock);
+    return result;
+}
+
+@end