内存泄漏解一波

1，AFNetWorking 内存泄漏

原理：

https://www.jianshu.com/p/4584ace111b2

解决方法：

网上很多文章都说AFNetWorking有内存泄漏问题，其实是使用者自己的问题，他们的解决方法是将AFHTTPSessionManager写成单例，用该单例进行网络请求。

其实不然。AFHTTPSessionManager继承于AFURLSessionManager，AFURLSessionManager有个属性session，session类型是NSURLSession，调用NSURLSession进行请求后，等请求完毕后调用session的finishTasksAndInvalidate方法，或者调用取消session的invalidateAndCancel方法，再或者将session属性置成nil，这样AFURLSessionManager就能正常释放，这样就不需要将AFHTTPSessionManager写成单例来使用了。NSURLSession将代理属性delegate强引用了，所以NSURLSession影响了其delegate的释放，调用其中的一个invalidate方法时，就会将其delegate引用计数减一，这样其delegate就能正常释放了，这里的delegate就是AFURLSessionManager。

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service.task = [self.sessionManager POST:service.urlString parameters:service.dataDictionary progress:nil success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject)                     {                         if (service.isShowLoadingView) [MBProgressHUD hideHUD];                         //网络请求成功(包含过滤服务器定义的错误码操作，实现在子类)                         [self responseHandler:responseObject service:service];                                               } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {                         //网络请求错误处理操作                         [service requestFail:ERROR_CODE_FAILURE errorMessage:REQUEST_FAILURE];                         if (service.isShowLoadingView) [MBProgressHUD hideHUD];                         //错误提示                         NSInteger statusCode = ((NSHTTPURLResponse *)task.response).statusCode;                         if (statusCode == 0)                         {                             statusCode = error.code;                         }                         [self requestFailWithService:service statusCode:statusCode]; //                        NSLog(@"URL==>%@\nErrorCode==>%d===ErrorMessage==>%@",service.urlString,ERROR_CODE_FAILURE,REQUEST_FAILURE);                     }];    [self.sessionManager.session finishTasksAndInvalidate];  //释放

　　

2,

GSKeyChain

将 原代码：

+ (NSMutableDictionary *)getKeychainQuery:(NSString *)service {
    return [NSMutableDictionary dictionaryWithObjectsAndKeys:
                   (__bridge_transfer id)kSecClassGenericPassword,(__bridge_transfer id)kSecClass,
                   service, (__bridge_transfer id)kSecAttrService,
                   service, (__bridge_transfer id)kSecAttrAccount,
                   (__bridge_transfer id)kSecAttrAccessibleAfterFirstUnlock,(__bridge_transfer id)kSecAttrAccessible,
                   nil];
}

换成：

static NSMutableDictionary * queryDIC;
+ (NSMutableDictionary *)getKeychainQuery:(NSString *)service {
   
    if (!queryDIC) {
        queryDIC =[NSMutableDictionary dictionaryWithObjectsAndKeys:
                   (__bridge_transfer id)kSecClassGenericPassword,(__bridge_transfer id)kSecClass,
                   service, (__bridge_transfer id)kSecAttrService,
                   service, (__bridge_transfer id)kSecAttrAccount,
                   (__bridge_transfer id)kSecAttrAccessibleAfterFirstUnlock,(__bridge_transfer id)kSecAttrAccessible,
                   nil];
    }
    return queryDIC;
}

 

+ (NSMutableDictionary *)getKeychainQuery:(NSString *)service KeychainHelper内存泄露

https://www.jianshu.com/p/4c1618c97410

 

 

3，

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///获取ssid + (NSString *)getWifiName {     NSArray* ifs = (__bridge_transfer id)CNCopySupportedInterfaces();     id info = nil;     for (NSString *ifnam in ifs){         info = (__bridge id)CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam);                   if (info && [info count])             break;     }     NSString *wifiname = info[@"SSID"];     return UNNULL_STRING(wifiname); }

　　

id bridge  换成   CFBridgingRelease

如：

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///获取ssid + (NSString *)getWifiName {     NSArray *ifs = CFBridgingRelease(CNCopySupportedInterfaces());     id info = nil;     for (NSString *ifnam in ifs){         info = CFBridgingRelease(CNCopyCurrentNetworkInfo((__bridge CFStringRef)ifnam));         if (info && [info count])             break;     }     NSString *wifiname = info[@"SSID"];     return UNNULL_STRING(wifiname); }

　　4 

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- (void)setModels {     //获取当前类     id infoClass = [self class];     unsigned int count = 0;     Ivar *members = class_copyIvarList([infoClass class], &count); //获取属性列表     for (int i = 0 ; i < count; i++) {  //遍历属性列表         Ivar var = members[i];         const char *memberType = ivar_getTypeEncoding(var); //获取变量类型         NSString *typeStr = [NSString stringWithCString:memberType encoding:NSUTF8StringEncoding];         //判断类型是否为字典——只处理物的模型中的属性         if ([typeStr isEqualToString:@"@\"NSDictionary\""]) {             const char *memberName = ivar_getName(var); //获取变量名称             [self setModelWithDicName:[NSString stringWithCString:memberName encoding:NSUTF8StringEncoding] channel:IOTBaseModelValueChangedChannel_Get];         }     }     free(members); //添加 }

　　

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1	Ivar *members = class_copyIvarList([infoClass class], &count); //获取属性列表 这句报了leak，加 free(members);  来释放掉。

原理：Runtime方法中的class_copyIvarList，class_copyMethodList这些方法返回的对象没有被手动释放导致的内存泄漏。因为这些是C实现的函数，是需要手动对函数返回值进行free的，不然则会导致内存泄露。= =。这里也顺便提醒平时需要注意对于C/C++的实现，当见到malloc/new分配的对象，就应该检查该对象有没有对应的free/delete操作，这些地方往往也是内存泄漏产生的地方。