blob: 5116cfe19d60bfdfff46e76f18fade05e644880f [file] [log] [blame]
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#import "ios/chrome/browser/snapshots/lru_cache.h"
#include <stddef.h>
#include <memory>
#include <unordered_map>
#include "base/containers/mru_cache.h"
#include "base/macros.h"
#include "base/memory/ptr_util.h"
#if !defined(__has_feature) || !__has_feature(objc_arc)
#error "This file requires ARC support."
#endif
namespace {
struct NSObjectEqualTo {
bool operator()(id<NSObject> obj1, id<NSObject> obj2) const {
return [obj1 isEqual:obj2];
}
};
struct NSObjectHash {
std::size_t operator()(id<NSObject> obj) const { return [obj hash]; }
};
template <class KeyType, class ValueType, class HashType>
struct MRUCacheNSObjectHashMap {
using Type =
std::unordered_map<KeyType, ValueType, HashType, NSObjectEqualTo>;
};
using NSObjectMRUCache = base::MRUCacheBase<id<NSObject>,
id<NSObject>,
NSObjectHash,
MRUCacheNSObjectHashMap>;
} // namespace
@implementation LRUCache {
std::unique_ptr<NSObjectMRUCache> _cache;
}
- (instancetype)initWithCacheSize:(NSUInteger)maxCacheSize {
if ((self = [super init])) {
_cache = base::MakeUnique<NSObjectMRUCache>(maxCacheSize);
}
return self;
}
- (NSUInteger)maxCacheSize {
return _cache->max_size();
}
- (id)objectForKey:(id<NSObject>)key {
auto it = _cache->Get(key);
if (it == _cache->end())
return nil;
return it->second;
}
- (void)setObject:(id<NSObject>)value forKey:(NSObject*)key {
_cache->Put([key copy], value);
}
- (void)removeObjectForKey:(id<NSObject>)key {
auto it = _cache->Peek(key);
if (it != _cache->end())
_cache->Erase(it);
}
- (void)removeAllObjects {
_cache->Clear();
}
- (NSUInteger)count {
return _cache->size();
}
- (BOOL)isEmpty {
return _cache->empty();
}
@end