我使用 NSInputstream
和 NSOutputstream
来建立连接并发送数据。我的流对象具有打开和关闭流的功能。我使用以下代码:
@interface Stream()
{
NSInputStream *inputStream;
NSOutputStream *outputStream;
}
-(id)init
{
self = [super init];
if (self)
{
inputStream = nil;
outputStream = nil;
}
return self;
}
-(int)streamOpenWithIp:(NSString *)ip withPortNumber:(int)portNumber;
{
CFReadStreamRef readStream;
CFWriteStreamRef writeStream;
CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, (__bridge CFStringRef)ip, portNumber, &readStream, &writeStream);
if(readStream && writeStream)
{
//Setup inpustream
inputStream = (__bridge NSInputStream *)readStream;
[inputStream setDelegate:self];
[inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[inputStream open];
//Setup outputstream
outputStream = (__bridge NSOutputStream *)writeStream;
[outputStream setDelegate:self];
[outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream open];
}
}
- (int)streamClose;
{
CFReadStreamSetProperty((__bridge CFReadStreamRef)(inputStream), kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
CFReadStreamSetProperty((__bridge CFReadStreamRef)(outputStream), kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
//Close and reset inputstream
[inputStream setDelegate:nil];
[inputStream close];
[inputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
inputStream = nil;
//Close and reset outputstream
[outputStream setDelegate:nil];
[outputStream close];
[outputStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
outputStream = nil;
}
当我多次打开和关闭流时,此代码工作正常。当我使用 Instruments 检查我的应用程序是否存在内存泄漏时,它说函数 CFStreamCreatePairWithSocketToHost
正在泄漏 72% 的内存。有人知道我做错了什么吗?我想不通。
最佳答案
在streamClose
方法中添加CFRelease((CFStreamRef)inputStream);
和CFRelease((CFStreamRef)outputStream);
。
当 CFStreamCreatePairWithSocketToHost
返回时,readStream
和 writeStream
的所有权将传递给您:
Ownership follows the Create Rule in Memory Management Programming Guide for Core Foundation.
即使使用 ARC,Core Foundation 对象也需要显式释放:
The compiler does not automatically manage the lifetimes of Core Foundation objects; you
must call CFRetain and CFRelease (or the corresponding type-specific variants) as dictated
by the Core Foundation memory management rules (see Memory Management Programming Guide
for Core Foundation).
或者,更改此行(以及 outputStream
的相应行):
inputStream = (__bridge NSInputStream *)readStream;
到:
inputStream = (__bridge_transfer NSInputStream *)readStream;
这是因为 readStream 有一个 ARC 不知道的未完成保留计数。通过授予 ARC 该指针的所有权,您将授予它在适当时间释放指针的权限。进一步阅读:1 , 2
关于ios - CFStreamCreatePairWithSocketToHost iOS 中的内存泄漏,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16320548/