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POAllocated data of NSMutableRequest object's body not being released
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copied!<p>In my app I have to perform a multipart POST request. In the request I have to send a file that is stored in the device's photo Library. After it is finished uploading and received the returned data, I send the request a release message, but Instruments shows me the data persists in the device's memory. </p> <p>This is how I create the request object:</p> <pre><code>NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init]; [request setCachePolicy:NSURLRequestReloadIgnoringLocalCacheData]; [request setHTTPShouldHandleCookies:YES]; [request setTimeoutInterval:30]; [request setHTTPMethod:@"POST"]; NSString *boundary = @"---------------------------14737809831466499882746641449"; // set Content-Type in HTTP header NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@", boundary]; [request setValue:contentType forHTTPHeaderField: @"Content-Type"]; // post body NSMutableData *body = [[NSMutableData alloc] init]; // add parts (all parts are strings) `parts` is a NSDictionary object for(id key in parts) { [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n", key] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[[NSString stringWithFormat:@"%@\r\n", [parts objectForKey:key]] dataUsingEncoding:NSUTF8StringEncoding]]; } // add files data - `file` is a ALAssetRepresentation object NSData *fileData; NSString *filename = [file filename]; Byte *buffer = (Byte*)malloc(file.size); NSUInteger buffered = [file getBytes:buffer fromOffset:0.0 length:file.size error:nil]; fileData = [[NSData alloc] initWithBytesNoCopy:buffer length:buffered freeWhenDone:YES]; if (fileData) { [body appendData:[[NSString stringWithFormat:@"--%@\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; if ([requestType isEqualToString:PUBLISH_TYPE_VC_MANDA]) { [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"attachment\"; filename=\"%@\"\r\n", filename] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[@"Content-Type: image/jpeg\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]]; } else { [body appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"file\"; filename=\"%@\"\r\n", filename] dataUsingEncoding:NSUTF8StringEncoding]]; [body appendData:[@"Content-Type: application/octet-stream\r\n\r\n" dataUsingEncoding:NSUTF8StringEncoding]]; } [body appendData:fileData]; [body appendData:[[NSString stringWithFormat:@"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]]; } [fileData release]; [body appendData:[[NSString stringWithFormat:@"--%@--\r\n", boundary] dataUsingEncoding:NSUTF8StringEncoding]]; // setting the body of the post to the reqeust [request setHTTPBody:body]; [body release]; // set the content-length NSString *postLength = [NSString stringWithFormat:@"%d", [body length]]; [request setValue:postLength forHTTPHeaderField:@"Content-Length"]; [request setValue:@"Keep-Alive" forHTTPHeaderField:@"Connection"]; // set URL `adress` is a NSURL object [request setURL:address]; //set cookie if (storedCookie) { NSDictionary *properties = [NSDictionary dictionaryWithObjectsAndKeys:[storedCookie name], NSHTTPCookieName, myDomain, NSHTTPCookieDomain,@"/",NSHTTPCookiePath, [storedCookie value], NSHTTPCookieValue, nil]; NSHTTPCookie *cookie = [NSHTTPCookie cookieWithProperties:properties]; NSArray* cookies = [NSArray arrayWithObjects: cookie, nil]; NSDictionary * headers = [NSHTTPCookie requestHeaderFieldsWithCookies:cookies]; [request setAllHTTPHeaderFields:headers]; } </code></pre> <p>After this, and after I received the response, i perform <code>[request release]</code> but the allocated bytes stay in memory.</p> <p>I ran <code>Instruments</code> in the Allocations mode, and it is claiming that there is an object of category <code>Malloc 91MB</code> (the size of the ALAsset I'm uploading). By looking at the Call tree, the Symbol that's taking up all the memory is <code>[NSConcreteMutableData appendBytes:length:]</code> inside the method described above.</p> <p>Why isn't it freeing the bytes ? And more importantly, why does it have to move the data to the device's memory ? I've seen apps like Facebook upload very large videos from the gallery without any memory problems.</p> <p>Thank you very much for your attention, any help or directions would be greatly appreciated</p> <p><strong>EDIT:</strong> Further investigation showed me that when I use <code>[request release]</code> the request object is released, but it's body isn't. Pretty weird behaviour...</p> <p><strong>EDIT2:</strong> I explicitly used <code>[request.HTTPBody release];</code> and the bytes were released. I still cannot believe that <code>[request release]</code> wasn't freeing it's body. Could this be a bug ?</p>

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