我使用输入和输出流实现了套接字。外部架构负责一次发送一个请求进行写入。
然而,如果任何请求没有返回no HasBytesAvailable,我需要从队列中删除该请求并通知请求超时。
对于所有其他请求,我能够正确地发送/接收数据,但如果任何一个请求超时,那么在此之后,hasspaceavable将永远不会被调用。
我的代码如下:
@CCCommandSocket的实现
@合成连接TimeoutTimer;@合成请求TimeoutTimer;
/**init**@params*ipAddress:camera socket的ip地址*portNumber:camera socket的端口地址**@return*socket类型的对象,它将向ipAddress发送连接请求,portNumber**/-(id)init{self=[super init];if(self){ip=@“192.168.42.1”;port=7878;
[self performSelectorOnMainThread:@selector(connectToCamera) withObject:nil waitUntilDone:YES];
bytesReceivedCondition = [[NSCondition alloc] init];
requestCompletedCondition = [[NSCondition alloc] init];
requestReadyToProcess = [[NSCondition alloc] init];
isBytesReceived = false;
isRequestCompleted = false;
isRequestReadyToProcess = false;
responseString = [[NSString alloc] init];
openBracesCount = 0;
mutex = [[NSLock alloc] init];
}
return self;
}
/**连接摄像机**/-(void)连接摄像机{NSString*urlStr=ip;
if (![urlStr isEqualToString:@""])
{
NSURL *website = [NSURL URLWithString:urlStr];
if (!website)
{
NSString* messageString = [NSString stringWithFormat:@"%@ is not a valid URL",website];
CCLog(LOG_ERROR, messageString);
return;
}
CFStreamCreatePairWithSocketToHost(NULL, (__bridge CFStringRef)(urlStr), port, &readStream, &writeStream);
//cast the CFStreams to NSStreams
inputStream = (__bridge_transfer NSInputStream *)readStream;
outputStream = (__bridge_transfer NSOutputStream *)writeStream;
//set the delegate
[inputStream setDelegate:self];
[outputStream setDelegate:self];
//schedule the stream on a run loop
[inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
//open the stream
[inputStream open];
[outputStream open];
if(readStream==NULL)
{
CCLog(LOG_INFO, @"readstream NULL");
}
if(writeStream == NULL)
{
CCLog(LOG_INFO, @"writeStream NULL");
}
[self startConnectionTimeoutTimer];
}
}
/**getIP**@返回*连接到套接字的IP地址*/-(NSString*)getIP{返回ip;}
/**getPort**@return*套接字连接的端口号*/-(int)getPort{return Port;}
>
(void)流:(NSStream*)流句柄事件:(NSStreamEvent)事件代码{
NSMutableArray*数组=[[NSMutableArray alloc]init];[数组addObject:stream];[array addObject:[NSNumber numberWithInt:eventCode]];
[self-performSelectorInBackground:@selector(myStream:)withObject:array];}
(void)myStream:(NSMutableArray*)数组{NSNumber*number=[array objectAtIndex:1];int eventCode=[number intValue];
switch(eventCode){case nsstreamventerroccurred:{CCLog(LOG_ERROR,@“In Command Socket nsstreamventerroccurred”);//[自断开];//[[ErrorDetails getInstance]报告错误:nsstreamventerroccurred];中断;}
//Read from stream
case NSStreamEventHasBytesAvailable:
{
CCLog(LOG_INFO, @"In Command Socket NSStreamEventHasBytesAvailable");
[self handleCommandPortDataReceived];
break;
}
//Write to stream
case NSStreamEventHasSpaceAvailable:
{
@synchronized(self)
{
[requestReadyToProcess lock];
while (isRequestReadyToProcess == false)
{
[requestReadyToProcess wait];
}
[requestReadyToProcess unlock];
CCLog(LOG_INFO,@"In Command Socket NSStreamEventHasSpaceAvailable");
@try
{
@synchronized(requestString)
{
if(requestString != nil)
{
if(outputStream != nil)
{
int dataSent;
uint8_t* data = (uint8_t *)[requestString cStringUsingEncoding:NSUTF8StringEncoding];
responseString = @"";
//[requestReadyToProcess lock];
isRequestReadyToProcess = false;
//[requestReadyToProcess signal];
dataSent = [outputStream write:data maxLength:strlen((char*)data)];
if(dataSent != -1)
{
NSString* message = [NSString stringWithFormat:@"Bytes written %d for request\n %@",dataSent, requestString];
CCLog(LOG_REQUEST, message);
requestString = nil;
isBytesReceived = false;
[bytesReceivedCondition lock];
while (isBytesReceived ==false)
{
[bytesReceivedCondition wait];
}
[requestCompletedCondition lock];
isRequestCompleted = true;
[requestCompletedCondition signal];
[requestCompletedCondition unlock];
[bytesReceivedCondition unlock];
}
else
{
CCLog(LOG_INFO, @"Command Socket : Request not sent (dataSent == -1)");
responseString = @"{ \"rval\": -104}";
CCLog(LOG_RESPONSE, responseString);
[self removeRequestFromQueue];
}
}
else
{
CCLog(LOG_INFO, @"in else :(outputStream != nil)");
}
}
}
}
@catch (NSException *e)
{
CCLog(LOG_WARNING, e.description);
}
}
break;
}
case NSStreamEventNone:
{
CCLog(LOG_INFO, @"In Command Socket NSStreamEventNone");
break;
}
case NSStreamEventOpenCompleted:
{
CCLog(LOG_INFO, @"In Command Socket NSStreamEventOpenCompleted");
[self stopConnectionTimeoutTimer];
break;
}
case NSStreamEventEndEncountered:
{
CCLog(LOG_INFO, @"Command Socket NSStreamEventEndEncountered");
[self disconnectWithNotification:YES];
break;
}
}}
/**执行**@参数*请求:通过套接字发送到摄像机的命令**@返回*响应:从摄像机收到的响应 * */ -(NSString*)执行请求:(NSString*)请求{CCLog(LOG_INFO,@"命令套接字执行请求");
[self performSelectorOnMainThread:@selector(startRequestTimeoutTimer) withObject:nil waitUntilDone:NO];
isRequestCompleted = false;
requestString = request;
responseString = @"";
[requestReadyToProcess lock];
isRequestReadyToProcess = true;
[requestReadyToProcess signal];
[requestReadyToProcess unlock];
[requestCompletedCondition lock];
while (isRequestCompleted ==false)
{
[requestCompletedCondition wait];
}
CCLog(LOG_INFO, @"Command Socket Execute request : request completed");
[requestCompletedCondition unlock];
CCLog(LOG_RESPONSE, responseString);
return responseString;
}
//当您启动连接时调用它-(void)startConnectionTimeoutTimer{[self-stopConnectionTimeoutTimer];//或者确保在调用此方法之前停止任何现有计时器
NSTimeInterval interval = 10.0; // Measured in seconds, is a double
self.connectionTimeoutTimer = [NSTimer scheduledTimerWithTimeInterval:interval
target:self
selector:@selector(handleConnectionTimeout)
userInfo:nil
repeats:NO];
}
>
(void)handleConnectionTimeout{responseString=@“{”rval\“:-103}”;CCLog(LOG_响应,responseString);
[自删除队列中的请求];
[自断开与通知:是];[自停止连接超时];}
//在启动连接时调用它—(void)startRequestTimeoutTimer{[self stopRequestTimeoutTimer];//或者确保在调用此方法之前停止任何现有计时器
NSTimeInterval interval = 20.0; // Measured in seconds, is a double
self.requestTimeoutTimer = [NSTimer scheduledTimerWithTimeInterval:interval
target:self
selector:@selector(handleRequestTimeout)
userInfo:nil
repeats:NO];
}
>
[自连接摄像机];[自停止请求超时器];[self-removequestfromqueue];}
//成功连接时调用此函数-(void)stopRequestTimeoutTimer{if(requestTimeoutTimer){[requestTimeoutTimer invalidate];requestTimeoutTimer=nil;}}}
-(void)disconnectWithNotification:(BOOL)shownnotification{CCLog(LOG_INFO,@“Socket Disconnected”);[inputStream close];[inputStream setDelegate:nil];[inputStream removeFromRunLoop:[nsrunlop currentRunLoop]forMode:NSDefaultRunLoopMode];inputStream=nil;
[outputStream close];
[outputStream setDelegate:nil];
[outputStream removeFromRunLoop:[NSRunLoop currentRunLoop]
forMode:NSDefaultRunLoopMode];
outputStream = nil;
[[CCCore getInstance] disconnectWithNotification:showNotification];
}
//成功连接时调用此函数-(void)stopConnectionTimeoutTimer{if(connectionTimeoutTimer){[connectionTimeoutTimer invalidate];connectionTimeoutTimer=nil;}如果(requestTimeoutTimer){[requestTimeoutTimer invalidate];requestTimeoutTimer=nil;}}}
-(void)handleCommandPortDataReceived{[mutex lock];[self-stopRequestTimeoutTimer];@try{long size=1024;uint8\u t buf[size];unsigned int len=0;
do
{
// read input stream into buffer
strcpy((char *)buf, "\0");
len = [inputStream read:buf maxLength:size];
//NSLog(@"Size = %ld Len = %d, Buf = %s",size, len, (char *)buf);
// Following code checks if we have received complete response by matching "{" and "}"
// from input stream. We continue to form response string unless braces are matched.
if (len > 0)
{
// Create nsdata from buffer
NSMutableData *_data = [[NSMutableData alloc] init];
[_data appendBytes:(const void *)buf length:len];
// create temporary string form nsdata
NSString* currentString = [[NSString alloc] initWithData:_data encoding:NSUTF8StringEncoding];
// check the occurances of { and } in current string
int currentOpeningBraceCount = [[currentString componentsSeparatedByString:@"{"] count] - 1;
int currentClosingBraceCount = [[currentString componentsSeparatedByString:@"}"] count] - 1;
openBracesCount = (openBracesCount + currentOpeningBraceCount) - currentClosingBraceCount;
responseString = [responseString stringByAppendingString:currentString];
// NSLog(@"Total:%d currentOpen:%d currentClose:%d\n\n",openBracesCount, currentOpeningBraceCount, currentClosingBraceCount);
// NSLog(@"Current String : %@\n\n",currentString);
// NSLog(@"Final String : %@",finalString);
// NSLog(@"+++++++++++++++++++++++++++++");
}
else
break;
} while (openBracesCount != 0);
NSRange range = [responseString rangeOfString:@"get_file_complete"];
if(range.location == NSNotFound)
{
//remove it from queue
[bytesReceivedCondition lock];
isBytesReceived = true;
[bytesReceivedCondition signal];
[bytesReceivedCondition unlock];
}
//responseString = @"";
}
@catch (NSException* e)
{
[self connectToCamera];
}
[mutex unlock];
}
-(void)removeRequestFromQueue{//将其从队列requestString=nil中删除;
[requestReadyToProcess lock];
isRequestReadyToProcess = false;
[requestReadyToProcess unlock];
[requestCompletedCondition lock];
isRequestCompleted = true;
[requestCompletedCondition signal];
[requestCompletedCondition unlock];
}
@结束
你在哪个操作系统版本上尝试这个??我遇到了类似的问题,在10.7及更高版本中一切都很好,但在10.6及以下版本中,我遇到了与您相同的问题我正在进行一些调试,但到目前为止还没有拿出一个好的解决方案。
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