Estou tentando fazer upload de arquivos grandes usando o AFNetworking e fazer o upload continuar quando o aplicativo estiver em segundo plano.

Posso fazer upload de arquivos, mas quando tento usar uma configuração em segundo plano - o aplicativo falha com o seguinte rastreamento de pilha: Exceção: EXC_BAD_ACCESS (código = 1, endereço = 0x8000001f))

_CFStreamSetDispatchQueue
-[__NSCFBackgroundDataTask captureStream:]
__70-[__NSCFBackgroundDataTask _onqueue_needNewBodyStream:withCompletion:]_block_invoke_2
_dispatch_call_block_and_release
_dispatch_queue_drain
_dispatch_queue_invoke
_dispatch_root_queue_drain
_dispatch_worker_thread3
_pthread_wqthread

Aqui está um exemplo de código:

Nota: Quando eu uso[NSURLSessionConfiguration defaultSessionConfiguration] o upload será bem-sucedido, mas não continuará quando o aplicativo estiver em segundo plano.[NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@"com.company.appname.uploadservice"] faz com que o aplicativo falhe.

NSMutableURLRequest *request = [[AFHTTPRequestSerializer serializer] multipartFormRequestWithMethod:@"POST" URLString:[uploadBundle.uploadUrl absoluteString] parameters:[uploadBundle getParameters] constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileURL:uploadBundle.fileDataUrl name:uploadBundle.fileName fileName:uploadBundle.fileName mimeType:uploadBundle.mimeType error:nil];
} error:nil];

Authentication *authentication = [Authentication getInstance];
[request addValue:authentication.token forHTTPHeaderField:@"token"];
[request addValue:authentication.authorization forHTTPHeaderField:@"Authorization"];

//NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@"com.company.appname.uploadservice"];
AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

NSProgress *progress = nil;
_currentUploadTask = [manager uploadTaskWithStreamedRequest:request progress:&progress completionHandler:^(NSURLResponse *response, id responseObject, NSError *error) {
    if (error) {
        NSLog(@"Error: %@", error);
    } else {
        NSLog(@"%@ %@", response, responseObject);
    }
}];