| /* |
| * |
| * Copyright 2015 gRPC authors. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| |
| #import "GRXForwardingWriter.h" |
| |
| @interface GRXForwardingWriter () <GRXWriteable> |
| @end |
| |
| @implementation GRXForwardingWriter { |
| GRXWriter *_writer; |
| id<GRXWriteable> _writeable; |
| } |
| |
| - (instancetype)init { |
| return [self initWithWriter:nil]; |
| } |
| |
| // Designated initializer |
| - (instancetype)initWithWriter:(GRXWriter *)writer { |
| if (!writer) { |
| return nil; |
| } |
| if (writer.state != GRXWriterStateNotStarted) { |
| [NSException raise:NSInvalidArgumentException |
| format:@"The writer argument must not have already started."]; |
| } |
| if ((self = [super init])) { |
| _writer = writer; |
| } |
| return self; |
| } |
| |
| // This is used to send a completion or an error to the writeable. It nillifies |
| // our reference to it in order to guarantee no more messages are sent to it, |
| // and to release it. |
| - (void)finishOutputWithError:(NSError *)errorOrNil { |
| id<GRXWriteable> writeable = _writeable; |
| _writeable = nil; |
| [writeable writesFinishedWithError:errorOrNil]; |
| } |
| |
| // This is used to stop the input writer. It nillifies our reference to it |
| // to release it. |
| - (void)finishInput { |
| GRXWriter *writer = _writer; |
| _writer = nil; |
| writer.state = GRXWriterStateFinished; |
| } |
| |
| #pragma mark GRXWriteable implementation |
| |
| - (void)writeValue:(id)value { |
| [_writeable writeValue:value]; |
| } |
| |
| - (void)writesFinishedWithError:(NSError *)errorOrNil { |
| _writer = nil; |
| [self finishOutputWithError:errorOrNil]; |
| } |
| |
| #pragma mark GRXWriter implementation |
| |
| - (GRXWriterState)state { |
| return _writer ? _writer.state : GRXWriterStateFinished; |
| } |
| |
| - (void)setState:(GRXWriterState)state { |
| if (state == GRXWriterStateFinished) { |
| _writeable = nil; |
| [self finishInput]; |
| } else { |
| _writer.state = state; |
| } |
| } |
| |
| - (void)startWithWriteable:(id<GRXWriteable>)writeable { |
| _writeable = writeable; |
| [_writer startWithWriteable:self]; |
| } |
| |
| - (void)finishWithError:(NSError *)errorOrNil { |
| [self finishOutputWithError:errorOrNil]; |
| [self finishInput]; |
| } |
| |
| @end |