OSCopyOnWriteSet.m

/**
 * Modified MIT License
 *
 * Copyright 2025 OneSignal
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * 1. The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * 2. All copies of substantial portions of the Software may only be used in connection
 * with services provided by OneSignal.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#import "OSCopyOnWriteSet.h"

@implementation OSCopyOnWriteSet

- (instancetype)init {
    if (self = [super init]) {
        _set = [[NSMutableSet alloc] init];
        _lock = [[NSLock alloc] init];
    }
    return self;
}

- (void)addObject:(id)object {
    [_lock lock];
    
    // Create a new copy and modify it
    NSMutableSet *newSet = [_set mutableCopy];
    [newSet addObject:object];
    
    // Update the internal set
    _set = newSet;
    
    [_lock unlock];
}

- (void)removeObject:(id)object {
    [_lock lock];

    // Create a new copy and modify it
    NSMutableSet *newSet = [_set mutableCopy];
    [newSet removeObject:object];
    
    // Update the internal set
    _set = newSet;
    
    [_lock unlock];
}

- (NSSet *)allObjects {
    // Read operation - no lock needed
    return _set;
}

@end