More documentation.
5 // Created by Jens Alfke on 5/18/08.
6 // Copyright 2008 Jens Alfke. All rights reserved.
10 #import "BLIPWriter.h"
11 #import "BLIP_Internal.h"
17 #define kDefaultFrameSize 4096
20 @implementation BLIPWriter
31 [_outBox makeObjectsPerformSelector: @selector(_connectionClosed) withObject: nil];
36 @synthesize numQueriesSent=_numQueriesSent;
41 return _outBox.count>0 || [super isBusy];
45 - (void) _queueMessage: (BLIPMessage*)msg isNew: (BOOL)isNew
47 int n = _outBox.count, index;
48 if( msg.urgent && n > 1 ) {
49 // High-priority gets queued after the last existing high-priority message,
50 // leaving one regular-priority message in between if possible.
51 for( index=n-1; index>0; index-- ) {
52 BLIPMessage *otherMsg = [_outBox objectAtIndex: index];
53 if( [otherMsg urgent] ) {
54 index = MIN(index+2, n);
56 } else if( isNew && otherMsg._bytesWritten==0 ) {
57 // But have to keep message starts in order
65 // Regular priority goes at the end of the queue:
69 _outBox = [[NSMutableArray alloc] init];
70 [_outBox insertObject: msg atIndex: index];
73 LogTo(BLIP,@"%@ queuing outgoing %@ at index %i",self,msg,index);
80 - (BOOL) sendMessage: (BLIPMessage*)message
83 Warn(@"%@: Attempt to send a message after the connection has started closing",self);
86 Assert(!message.sent,@"message has already been sent");
87 [self _queueMessage: message isNew: YES];
92 - (BOOL) sendRequest: (BLIPRequest*)q response: (BLIPResponse*)response
95 [q _assignedNumber: ++_numQueriesSent];
97 [response _assignedNumber: _numQueriesSent];
98 [(BLIPReader*)self.reader _addPendingResponse: response];
101 return [self sendMessage: q];
105 - (void) queueIsEmpty
107 if( _outBox.count > 0 ) {
108 // Pop first message in queue:
109 BLIPMessage *msg = [[_outBox objectAtIndex: 0] retain];
110 [_outBox removeObjectAtIndex: 0];
112 // As an optimization, allow message to send a big frame unless there's a higher-priority
113 // message right behind it:
114 size_t frameSize = kDefaultFrameSize;
115 if( msg.urgent || _outBox.count==0 || ! [[_outBox objectAtIndex: 0] urgent] )
118 if( [msg _writeFrameTo: self maxSize: frameSize] ) {
119 // add it back so it can send its next frame later:
120 [self _queueMessage: msg isNew: NO];
124 LogTo(BLIPVerbose,@"%@: no more work for writer",self);
134 Copyright (c) 2008, Jens Alfke <jens@mooseyard.com>. All rights reserved.
136 Redistribution and use in source and binary forms, with or without modification, are permitted
137 provided that the following conditions are met:
139 * Redistributions of source code must retain the above copyright notice, this list of conditions
140 and the following disclaimer.
141 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions
142 and the following disclaimer in the documentation and/or other materials provided with the
145 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
146 IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
147 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
148 BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
149 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
150 PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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