I am working on streaming part of application. I needed to put streaming process on the background thread that it uses NSinputstream and NSOutputstream .
then I send http commands over this streaming channel on the same thread.
I receive the NSStreamEventOpenCompleted and NSStreamEventHasSpaceAvailable and also I receive the http request on the server side , but it doesn't raise the EVENT HAS BYTES AVAILABLE . and I can not receive the responses ... I dont know what is the problem . here is some part of my codes :
Thread that I am using :
- (void)backgroundThread
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
NSLock *threadLock = [[NSLock alloc] init];
while (quitProcess)
{
if (queue.count > 0)
{
[threadLock lock];// Blocks other threads
cmdQueue = [queue copy];
[queue removeAllObjects];
[threadLock unlock];
}
else
{
sleep(1);
}
if (cmdQueue){
for (NSString* cmd in cmdQueue)
{
if ([cmd isEqualToString:#"subscribe"]){
[self openCmdLine];
}else if ([cmd isEqualToString:#"dataConnect"]){
[self dataConnect];
}else if ([cmd isEqualToString:#"openCmdLine"]){
[self openCmdLine];
}else if ([cmd isEqualToString:#"closeCmdLine"]){
[self closeCmdLine];
}else if ([cmd isEqualToString:#"handshake"]){
sleep(5);
[self cmdHandshake];
}else if ([cmd isEqualToString:#"topvol"]){
[self cmdTopVol];
}else{
//subscribe or unsubscribe
}
}
cmdQueue = nil;
}
}
[pool drain];
}
the reason is because of NSRunloop , that is responsible for connection call back, you should place it in your code
Related
I am using AVFoundation framework to Grab Screen.
I'm registered queue like this
*dispatch_sync (mainQueue, ^{
BOOL ret;
if (captureScreen)
ret = [self openScreenInput];
else
ret = [self openDeviceInput];
if (!ret)
return;
output = [[AVCaptureVideoDataOutput alloc] init];
[output setSampleBufferDelegate:self
queue:workerQueue];
output.alwaysDiscardsLateVideoFrames = YES;
output.videoSettings = nil; /* device native format */
session = [[AVCaptureSession alloc] init];
[session addInput:input];
[session addOutput:output];
*successPtr = YES;
});*
As Soon as it grab the buffers those will get delivered to workerQueue.
In CaptureOutput code -
*- (void)captureOutput:(AVCaptureOutput *)captureOutput
didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer
fromConnection:(AVCaptureConnection *)connection
{
GstClockTime timestamp, duration;
[bufQueueLock lock];
if (stopRequest) {
[bufQueueLock unlock];
return;
}
if ([bufQueue count] == BUFFER_QUEUE_SIZE)
{
[bufQueue removeLastObject];
}
[bufQueue insertObject:(__bridge id)sampleBuffer
atIndex:0];
[bufQueueLock unlockWithCondition:HAS_BUFFER_OR_STOP_REQUEST];
}*
But when render the delivered buffers I'm getting about 250-300ms delay.This is too just because of Grabber.
If anyone has solution please post it.
Thanks In advance
I have a PDFDocument where it has some actions on pages like delete,crop,rotate etc.
So when I click on the delete button and click on save(current thread : main thread)
-(void)save
{
// -- process deleted pages first
for( NSString* deletedPageId in self.deletedPageIdList )
{
[self.pdfCoordinator removePageWithId:deletedPageId];
}
// -- wait for all pages to delete before continuing
[self.pdfCoordinator waitUntilAllOperationsAreFinished];
// few lines of code after this should run only when the above code finishes its execution
// code to save the changes in the pdf to managedObject context
}
The code for removePageWithId:
- (void) removePageWithId:(NSString*)pageId
{
NRMPDFOperation *op = [[NRMPDFOperation alloc] initWithNRMPDF:self
pageId:pageId
selector:#selector(removePageOpImpl:)
args:nil];
[self addOperation:op];
[op release];
}
above code creates an operation and adds it to the operation queue for each deletion of the page
code for removePageOpImpl:
- (NSError *)removePageOpImpl:(NRMPDFOperation *)op
{
NSError* error = [self loadDocument];
if( !error )
{
NSUInteger index = [self pageIndexForId:[op pageId]];
if( index < [self pageCount] )
{
[[self pdfDocument] removePageAtIndex:index];
[[self mutablePageIdList] removeObjectAtIndex:index];
[self updatePageLabelsFromIndex:index];
[self updateChangeCount:NSChangeDone];
self.contentsChanged = YES;
}
else
{
// TODO: error
}
}
return error;
}
In the removePageOpImpl: method the line of code
[[self pdfDocument] removePageAtIndex:index]; internally executing some tasks on main thread(but we are making the main thread to wait until this operation finishes).which causes the deadlock.
I tried to execute the code inside removePageOpImpl: in an asynchronous dispatch queue to avoid the deadlock.below is the code for that
- (NSError *)removePageOpImpl:(NRMPDFOperation *)op
{
NSError* error = [self loadDocument];
if( !error )
{
NSUInteger index = [self pageIndexForId:[op pageId]];
if( index < [self pageCount] )
{
dispatch_async(dispatch_get_main_queue(), ^{
[[self pdfDocument] removePageAtIndex:index];
[[self mutablePageIdList] removeObjectAtIndex:index];
[self updatePageLabelsFromIndex:index];
[self updateChangeCount:NSChangeDone];
self.contentsChanged = YES;
});
}
else
{
// TODO: error
}
}
return error;
}
Now I am out from the deadlock. But another issue is by putting the above code into asynchronous block the code which should run after this tasks is executing before this, because of that my app is not behaving as expected.
Code inside waitUntilAllOperationsAreFinished method
- (void) addOperation:(NRMPDFOperation*)operation
{
[_operationSet addObject:operation];
[[self operationQueue] addOperation:operation];
}
- (void) waitUntilAllOperationsAreFinished
{
[[self operationQueue] waitUntilAllOperationsAreFinished];
}
- (NSOperationQueue *)operationQueue
{
if( !_operationQueue )
{
NSOperationQueue *queue = [[NSOperationQueue alloc] init];
[queue setMaxConcurrentOperationCount:1];
_operationQueue = queue;
}
return _operationQueue;
}
This is how the original Save method looks like :
- (void)saveDocumentWithDelegate:(id)delegate didSaveSelector:(SEL)didSaveSelector contextInfo:(void *)contextInfo
{
// TODO: don't just ignore saveOperation
__block BOOL success = YES;
__block NSError *error = nil;
/* write back field changes */
if ([item hasChangesInEditFieldsetFor:#"values"] )
{
//Some code
}
if( self.isPDFEdited )
{
// -- process deleted pages first
for( NSString* deletedPageId in self.deletedPageIdList )
{
[self.itemPDFCoordinator removePageWithId:deletedPageId];
}
// -- wait for all pages to delete before continuing
[self.itemPDFCoordinator waitUntilAllOperationsAreFinished];
// -- replace the search text any pages we deleted
if( [self.deletedPageIdList count] )
{
[self.item setValue:[self.editPDF string] forKeyPath:#"dict.values._searchText"];
}
NSMutableDictionary* originalRotations = [NSMutableDictionary dictionaryWithCapacity:
[self.itemPDFCoordinator pageCount]];
for( NSString* pageId in self.itemPDFCoordinator.pageIdList )
{
NSInteger rotation = [[self.itemPDFCoordinator pageForId:pageId] rotation];
[originalRotations setObject:[NSNumber numberWithInteger:rotation] forKey:pageId];
}
// -- now process actions on remaining pages (crop, rotate, and convert to b&w)
BOOL didCropAnyPages = NO;
NSMutableArray* convertToBwJobs = [NSMutableArray array];
for( NSString* pageId in [self.pageActionDict allKeys] )
{
NSArray* actions = [self.pageActionDict objectForKey:pageId];
for( NSDictionary* action in actions )
{
NSNumber* rotationNumber = [action objectForKey:#"rotation"];
NSValue* cropRectVal = [action objectForKey:#"cropRect"];
NSNumber* convertToBlackAndWhite = [action objectForKey:#"convertToBlackAndWhite"];
if( rotationNumber )
{
[self.itemPDFCoordinator rotateByDegrees:[rotationNumber integerValue]
forPageWithID:pageId];
}
else if( cropRectVal )
{
[self.itemPDFCoordinator setNormalizedBounds:[cropRectVal rectValue]
forBox:kPDFDisplayBoxCropBox
forPageWithID:pageId];
// -- set a flag so we know to recrop the entire document
didCropAnyPages = YES;
}
else if( [convertToBlackAndWhite boolValue] )
{
NSUInteger pageIndex = [self.itemPDFCoordinator pageIndexForId:pageId];
NRMJob* job = [NRMAppJobFactory convertToBlackAndWhiteJobForItem:self.item
pageIndex:pageIndex];
[convertToBwJobs addObject:job];
}
}
}
// -- reapply crop box to any cropped pages
if( didCropAnyPages )
{
[self.itemPDFCoordinator applyCropBoxToAllPages];
}
[self.itemPDFCoordinator waitUntilAllOperationsAreFinished];
for( NRMJob* job in convertToBwJobs )
{
if( ![[self.masterDocument docjob] addJob:job forItem:self.item error:&error] )
[NSApp presentError:error];
else
[job waitUntilDone];
}
// -- make sure document attributes are updated
NSDictionary *docDict = [self.itemPDFCoordinator documentAttributes];
NSDictionary *newDict = [(NRMItem *)item updateDocumentAttributes:docDict];
if (![newDict isEqualToDictionary:docDict])
[self.itemPDFCoordinator setDocumentAttributes:newDict];
[self.itemPDFCoordinator waitUntilAllOperationsAreFinished];
// -- check if we need to reprocess any pages
for( NSString* pageId in self.itemPDFCoordinator.pageIdList )
{
NSInteger oldRotation = [[originalRotations objectForKey:pageId] integerValue];
NSInteger newRotation = [[self.itemPDFCoordinator pageForId:pageId] rotation];
if( oldRotation != newRotation )
{
// -- if it's an image page and we already have OCR data for it, we should reanalyze
NSUInteger pageIndex = [self.itemPDFCoordinator pageIndexForId:pageId];
BOOL isPageImage = [self.itemPDFCoordinator isImagePageAtIndex:pageIndex DPI:NULL];
if( isPageImage && [item OCRDataForPageIndex:pageIndex] )
{
NRMJob* job = [NRMAppJobFactory reprocessPageJobForItem:self.item
pageIndex:pageIndex];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(reanalyzeJobFinished:)
name:kNRMJobFinishedNotification
object:job];
success = [[self.masterDocument docjob] addJob:job forItem:self.item error:&error];
if( !success )
{
if( error )
[self presentError:error];
}
//goto bail;
}
}
}
//Force Save of PDF to Disk
[self.itemPDFCoordinator setManagedObjectContext:[item managedObjectContext]];
[self.itemPDFCoordinator saveChanges];
}
if( success )
{
[self updateChangeCount:NSChangeCleared];
if( self.isPDFEdited )
{
// !CLEARSPLIT! please do not remove this comment
[self.item setValue:nil forKeyPath:#"dict.values._splitId"];
if( ![self loadPDFForItem:item error:&error] )
goto bail;
}
}
bail:
if( error )
[self presentError:error];
if( delegate )
{
/* signature:
- (void)document:(NSDocument *)document didSave:(BOOL)didSaveSuccessfully contextInfo:(void *)contextInfo;
*/
objc_msgSend( delegate, didSaveSelector, self, (error ? NO : YES), contextInfo );
}
}
can anyone suggest me how can I get out of this issue.
Rather than calling waitUntilAllOperationsAreFinished (which blocks a thread), I'd suggest specifying an additional completion operation, which you can make dependent upon the other operations finishing:
-(void)save {
NSOperation *completionOperation = [NSBlockOperation blockOperationWithBlock:^{
// whatever you want to do when it's done
}];
for (NSString* deletedPageId in self.deletedPageIdList) {
NSOperation *operation = [self.pdfCoordinator removePageWithId:deletedPageId];
[completionOperation addDependency:operation];
}
// add this completionOperation to a queue, but it won't actually start until the other operations finish
[queue addOperation:completionOperation];
}
Clearly this assumes that you change removePageWithId to return the operation it added to the queue:
- (NSOperation *)removePageWithId:(NSString*)pageId {
NRMPDFOperation *operation = [[NRMPDFOperation alloc] initWithNRMPDF:self
pageId:pageId
selector:#selector(removePageOpImpl:)
args:nil];
[self addOperation:operation];
[operation release];
return operation;
}
This way, you're not blocking any thread waiting for the operations to finish, but simply specify what to do when they do finish.
How can a connection be closed when the NSOutputStream has finished sending data?
After searching around i have found that the event NSStreamEventEndEncountered is only called if the server drops the connection. not if the OutputStream has finished the data to send.
StreamStatus is Always returning 0 (connection closed) or 2 (connection open) but never 4 (writing data).
since both methods mentioned above are not telling me enough about the write process i am not able to find a way do determine if the Stream is still writing or if it has finished and i can close the connection now.
After 5 days of googleling and trying i am totally out of ideas... Any help appreciated. Thanks
EDIT ADDED CODE AS REQUESTED:
- (void)startSend:(NSString *)filePath
{
BOOL success;
NSURL * url;
assert(filePath != nil);
assert([[NSFileManager defaultManager] fileExistsAtPath:filePath]);
assert( [filePath.pathExtension isEqual:#"png"] || [filePath.pathExtension isEqual:#"jpg"] );
assert(self.networkStream == nil); // don't tap send twice in a row!
assert(self.fileStream == nil); // ditto
// First get and check the URL.
...
....
.....
// If the URL is bogus, let the user know. Otherwise kick off the connection.
...
....
.....
if ( ! success) {
self.statusLabel.text = #"Invalid URL";
} else {
// Open a stream for the file we're going to send. We do not open this stream;
// NSURLConnection will do it for us.
self.fileStream = [NSInputStream inputStreamWithFileAtPath:filePath];
assert(self.fileStream != nil);
[self.fileStream open];
// Open a CFFTPStream for the URL.
self.networkStream = CFBridgingRelease(
CFWriteStreamCreateWithFTPURL(NULL, (__bridge CFURLRef) url)
);
assert(self.networkStream != nil);
if ([self.usernameText.text length] != 0) {
success = [self.networkStream setProperty:self.usernameText.text forKey:(id)kCFStreamPropertyFTPUserName];
assert(success);
success = [self.networkStream setProperty:self.passwordText.text forKey:(id)kCFStreamPropertyFTPPassword];
assert(success);
}
self.networkStream.delegate = self;
[self.networkStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
///////******** LINE ADDED BY ME TO DISONNECT FROM FTP AFTER CLOSING CONNECTION *********////////////
[self.networkStream setProperty:(id)kCFBooleanFalse forKey:(id)kCFStreamPropertyFTPAttemptPersistentConnection];
///////******** END LINE ADDED BY ME *********////////////
[self.networkStream open];
// Tell the UI we're sending.
[self sendDidStart];
}
}
- (void)stopSendWithStatus:(NSString *)statusString
{
if (self.networkStream != nil) {
[self.networkStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
self.networkStream.delegate = nil;
[self.networkStream close];
self.networkStream = nil;
}
if (self.fileStream != nil) {
[self.fileStream close];
self.fileStream = nil;
}
[self sendDidStopWithStatus:statusString];
}
- (void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode
// An NSStream delegate callback that's called when events happen on our
// network stream.
{
#pragma unused(aStream)
assert(aStream == self.networkStream);
switch (eventCode) {
case NSStreamEventOpenCompleted: {
[self updateStatus:#"Opened connection"];
} break;
case NSStreamEventHasBytesAvailable: {
assert(NO); // should never happen for the output stream
} break;
case NSStreamEventHasSpaceAvailable: {
[self updateStatus:#"Sending"];
// If we don't have any data buffered, go read the next chunk of data.
if (self.bufferOffset == self.bufferLimit) {
NSInteger bytesRead;
bytesRead = [self.fileStream read:self.buffer maxLength:kSendBufferSize];
if (bytesRead == -1) {
[self stopSendWithStatus:#"File read error"];
} else if (bytesRead == 0) {
[self stopSendWithStatus:nil];
} else {
self.bufferOffset = 0;
self.bufferLimit = bytesRead;
}
}
// If we're not out of data completely, send the next chunk.
if (self.bufferOffset != self.bufferLimit) {
NSInteger bytesWritten;
bytesWritten = [self.networkStream write:&self.buffer[self.bufferOffset] maxLength:self.bufferLimit - self.bufferOffset];
assert(bytesWritten != 0);
if (bytesWritten == -1) {
[self stopSendWithStatus:#"Network write error"];
} else {
self.bufferOffset += bytesWritten;
}
}
} break;
case NSStreamEventErrorOccurred: {
[self stopSendWithStatus:#"Stream open error"];
} break;
case NSStreamEventEndEncountered: {
// FOR WHATEVER REASON THIS IS NEVER CALLED!!!!
} break;
default: {
assert(NO);
} break;
}
}
There can be two interpretations to your question. If what you are asking is "I have a NSOutputStream and I'm finished writing to it how do I signal this?" then the answer is as simple as call the close method on it.
Alternately, If what you are really saying is "I have a NSInputStream and I want to know when I've reached the end-of-stream" then you can look at hasBytesAvailable or streamStatus == NSStreamStatusAtEnd.
For your information, to actually get the status NSStreamStatusWriting you would need to be calling the streamStatus method from another thread while this thread is calling write:maxLength:.
--- Edit: Code Suggestion
The reason you would never get notified is that an output stream is never finished (unless it's a fixed size stream, which an FTP stream is not). It's the input stream that gets "finished" at which point you can close your output stream. That's the answer to your original question.
As a further suggestion, I would skip run loop scheduling and the "event processing" except for handling errors on the output stream. Then I would put the read/write code into a NSOperation subclass and send it off into a NSOperationQueue. By keeping a reference to the NSOperations in that queue you would be able to cancel them easily and even show a progress bar by adding a percentComplete property. I've tested the code below and it works. Replace my memory output stream with your FTP output stream. You will notice that I have skipped the validations, which you should keep of course. They should probably be done outside the NSOperation to make it easier to query the user.
#interface NSSendFileOperation : NSOperation<NSStreamDelegate> {
NSInputStream *_inputStream;
NSOutputStream *_outputStream;
uint8_t *_buffer;
}
#property (copy) NSString* sourceFilePath;
#property (copy) NSString* targetFilePath;
#property (copy) NSString* username;
#property (copy) NSString* password;
#end
#implementation NSSendFileOperation
- (void) main
{
static int kBufferSize = 4096;
_inputStream = [NSInputStream inputStreamWithFileAtPath:self.sourceFilePath];
_outputStream = [NSOutputStream outputStreamToMemory];
_outputStream.delegate = self;
[_inputStream open];
[_outputStream open];
_buffer = calloc(1, kBufferSize);
while (_inputStream.hasBytesAvailable) {
NSInteger bytesRead = [_inputStream read:_buffer maxLength:kBufferSize];
if (bytesRead > 0) {
[_outputStream write:_buffer maxLength:bytesRead];
NSLog(#"Wrote %ld bytes to output stream",bytesRead);
}
}
NSData *outputData = [_outputStream propertyForKey:NSStreamDataWrittenToMemoryStreamKey];
NSLog(#"Wrote a total of %lu bytes to output stream.", outputData.length);
free(_buffer);
_buffer = NULL;
[_outputStream close];
[_inputStream close];
}
- (void) stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode
{
// Handle output stream errors such as disconnections here
}
#end
int main (int argc, const char * argv[])
{
#autoreleasepool {
NSOperationQueue *sendQueue = [[NSOperationQueue alloc] init];
NSSendFileOperation *sendOp = [[NSSendFileOperation alloc] init];
sendOp.username = #"test";
sendOp.password = #"test";
sendOp.sourceFilePath = #"/Users/eric/bin/data/english-words.txt";
sendOp.targetFilePath = #"/Users/eric/Desktop/english-words.txt";
[sendQueue addOperation:sendOp];
[sendQueue waitUntilAllOperationsAreFinished];
}
return 0;
}
I am trying to create a method that will return me a ALAsset for a given asset url. (I need upload the asset later and want to do it outside the result block with the result.)
+ (ALAsset*) assetForPhoto:(Photo*)photo
{
ALAssetsLibrary* library = [[[ALAssetsLibrary alloc] init] autorelease];
__block ALAsset* assetToReturn = nil;
NSURL* url = [NSURL URLWithString:photo.assetUrl];
NSLog(#"assetForPhoto: %#[", url);
[library assetForURL:url resultBlock:^(ALAsset *asset)
{
NSLog(#"asset: %#", asset);
assetToReturn = asset;
NSLog(#"asset: %# %d", assetToReturn, [assetToReturn retainCount]);
} failureBlock:^(NSError *error)
{
assetToReturn = nil;
}];
NSLog(#"assetForPhoto: %#]", url);
NSLog(#"assetToReturn: %#", assetToReturn); // Invalid access exception coming here.
return assetToReturn;
}
The problem is assetToReturn gives an EXC_BAD_ACCESS.
Is there some problem if I try to assign pointers from inside the block? I saw some examples of blocks but they are always with simple types like integers etc.
A few things:
You must keep the ALAssetsLibrary instance around that created the ALAsset for as long as you use the asset.
You must register an observer for the ALAssetsLibraryChangedNotification, when that is received any ALAssets you have and any other AssetsLibrary objects will need to be refetched as they will no longer be valid. This can happen at any time.
You shouldn't expect the -assetForURL:resultBlock:failureBlock:, or any of the AssetsLibrary methods with a failureBlock: to be synchronous. They may need to prompt the user for access to the library and will not always have their blocks executed immediately. It's better to put actions that need to happen on success in the success block itself.
Only if you absolutely must make this method synchronous in your app (which I'd advise you to not do), you'll need to wait on a semaphore after calling assetForURL:resultBlock:failureBlock: and optionally spin the runloop if you end up blocking the main thread.
The following implementation should satisfy as a synchronous call under all situations, but really, you should try very hard to make your code asynchronous instead.
- (ALAsset *)assetForURL:(NSURL *)url {
__block ALAsset *result = nil;
__block NSError *assetError = nil;
dispatch_semaphore_t sema = dispatch_semaphore_create(0);
[[self assetsLibrary] assetForURL:url resultBlock:^(ALAsset *asset) {
result = [asset retain];
dispatch_semaphore_signal(sema);
} failureBlock:^(NSError *error) {
assetError = [error retain];
dispatch_semaphore_signal(sema);
}];
if ([NSThread isMainThread]) {
while (!result && !assetError) {
[[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantFuture]];
}
}
else {
dispatch_semaphore_wait(sema, DISPATCH_TIME_FOREVER);
}
dispatch_release(sema);
[assetError release];
return [result autorelease];
}
You should retain and autorelease the asset:
// ...
assetToReturn = [asset retain];
// ...
return [assetToReturn autorelease];
I'm trying to learn how to use the NSInputStream class on the iPhone using a unit test. I can get the NSStream to read data from a file using the polling method but for some reason the delegate/event method is not working.
I've posted the relevant code below. Please ignore memory leak errors and such since I'm just trying to ensure I know how to use the NSStream class in a sandboxed environment before rolling it into my larger project.
I'm wondering if maybe I'm missing something with regards to how the run loops work?
This is the logic test that creates a streamer class to read from a file.
#import "StreamingTests.h"
#import "Streamer.h"
#implementation StreamingTests
- (void) testStream {
NSLog(#"Starting stream test.");
Streamer * streamer = [[Streamer alloc] init];
streamer.usePolling = NO;
streamer.readingStream = YES;
NSThread * readThread = [[NSThread alloc] initWithTarget:streamer selector:#selector(startStreamRead:) object:nil];
[readThread start];
while(streamer.readingStream) {
[NSThread sleepForTimeInterval:0.5];
}
[readThread cancel];
}
#end
This is a simple test helper object that reads from an NSStream. When usePolling == YES it read data and outputs the appropriate NSLog messages. However, if usePolling == NO the delegate stream event function is never called.
#implementation Streamer
#synthesize readingStream, usePolling;
- (void) startStreamRead:(NSObject*) context {
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
NSLog(#"starting stream read.");
readingStream = YES;
/*
NSURL * url = [NSURL URLWithString:#"http://www.google.com"];
NSLog(#"Loading: %#",[url description]);
NSInputStream * inStream = [[NSInputStream alloc] initWithURL:url];
*/
NSInputStream * inStream = [[NSInputStream alloc] initWithFileAtPath:#"sample.ttc"];
if(!usePolling) {
[inStream setDelegate: self];
[inStream scheduleInRunLoop: [NSRunLoop currentRunLoop]
forMode: NSDefaultRunLoopMode];
}
[inStream open];
if(usePolling) {
while(1) {
if([inStream hasBytesAvailable]) {
uint8_t buf[1024];
unsigned int len = 0;
len = [(NSInputStream *)inStream read:buf maxLength:1024];
NSLog(#"Read: %d",len);
}
NSStreamStatus status = [inStream streamStatus];
if(status != NSStreamStatusOpen && status != NSStreamStatusOpening) {
NSLog(#"Stream not open.");
break;
}
}
readingStream = NO;
NSStreamStatus status = [inStream streamStatus];
NSError * error = [inStream streamError];
NSLog(#"Status: %d Error Desc: %# Reason: %#",(int)status,[error localizedDescription], [error localizedFailureReason]);
[pool release];
}
}
- (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)eventCode {
NSMutableData * _data = nil;
NSNumber * bytesRead = nil;
NSLog(#"Event fired.");
switch(eventCode) {
case NSStreamEventHasBytesAvailable:
{
if(!_data) {
_data = [[NSMutableData data] retain];
}
uint8_t buf[1024];
unsigned int len = 0;
len = [(NSInputStream *)stream read:buf maxLength:1024];
if(len) {
[_data appendBytes:(const void *)buf length:len];
// bytesRead is an instance variable of type NSNumber.
//[bytesRead setIntValue:[bytesRead intValue]+len];
NSLog(#"Read %d bytes",len);
} else {
NSLog(#"no buffer!");
}
break;
}
case NSStreamEventEndEncountered:
{
[stream close];
[stream removeFromRunLoop:[NSRunLoop currentRunLoop]
forMode:NSDefaultRunLoopMode];
[stream release];
stream = nil; // stream is ivar, so reinit it
readingStream = NO;
break;
}
default:
{
NSLog(#"Another event occurred.");
break;
}
// continued ...
}
}
#end
Thanks in advance,
b
The reason for it should be that the run loop is blocked since the unit test is executing. You could refer to the NSRunLoop documentation where the method
runUntilDate:
might help you to run the main run loop in the thread of execution of the unit test like this:
[[NSRunLoop mainRunLoop] runUntilDate:[NSDate dateWithTimeIntervalSinceNow:1]];
This lets the run loop run for 1 second giving it time to process part of your file. It should be noted that this does not provide a reliable way for unit testing (since the time interval might differ depending on run loop size) and may then be unsuitable. By giving your unit an interface that could be used to check the status of the input stream read operation (with a reading finished state) such as
-(BOOL)hasFinishedReadingFile
the unit test could repeatedly execute the run loop until the above method returns TRUE and the file is read completely.
Addition: This question on stackoverflow also deals with the problem in a different way.