blob: 03b0359278a24fbf7b3578166240fb4796102477 [file] [log] [blame]
/*
*
* Copyright 2015, Google Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Google Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#import <Foundation/Foundation.h>
#import "GRXWriteable.h"
#import "GRXWriter.h"
/**
* A buffered pipe is a Writer that also acts as a Writeable.
* Once it is started, whatever values are written into it (via -writeValue:) will be propagated
* immediately, unless flow control prevents it.
* If it is throttled and keeps receiving values, as well as if it receives values before being
* started, it will buffer them and propagate them in order as soon as its state becomes Started.
* If it receives an error (via -writesFinishedWithError:), it will drop any buffered values and
* propagate the error immediately.
*
* Beware that a pipe of this type can't prevent receiving more values when it is paused (for
* example if used to write data to a congested network connection). Because in such situations the
* pipe will keep buffering all data written to it, your application could run out of memory and
* crash. If you want to react to flow control signals to prevent that, instead of using this class
* you can implement an object that conforms to GRXWriter.
*
* Thread-safety:
* The methods of an object of this class should not be called concurrently from different threads.
*/
@interface GRXBufferedPipe : GRXWriter<GRXWriteable>
/** Convenience constructor. */
+ (instancetype)pipe;
@end