Source/ProtocolClient.m

   1 /*
   2  * MacGDBp
   3  * Copyright (c) 2013, Blue Static <http://www.bluestatic.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it under the terms of the GNU
   6  * General Public License as published by the Free Software Foundation; either version 2 of the
   7  * License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
  10  * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with this program; if not,
  14  * write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
  15  */
  16
  17 #import "ProtocolClient.h"
  18
  19 #import "AppDelegate.h"
  20 #import "LoggingController.h"
  21
  22 @implementation ProtocolClient
  23
  24 - (id)initWithDelegate:(NSObject<ProtocolClientDelegate>*)delegate {
  25   if ((self = [super init])) {
  26     _delegate = delegate;
  27     _delegateThread = [NSThread currentThread];
  28     _lock = [[NSRecursiveLock alloc] init];
  29   }
  30   return self;
  31 }
  32
  33 - (void)dealloc {
  34   [_lock release];
  35   [super dealloc];
  36 }
  37
  38 - (BOOL)isConnected {
  39   return [_messageQueue isConnected];
  40 }
  41
  42 - (void)connectOnPort:(NSUInteger)port {
  43   assert(!_messageQueue);
  44   _messageQueue = [[MessageQueue alloc] initWithPort:port delegate:self];
  45   [_messageQueue connect];
  46 }
  47
  48 - (void)disconnect {
  49   [_messageQueue disconnect];
  50 }
  51
  52 - (NSNumber*)sendCommandWithFormat:(NSString*)format, ... {
  53   // Collect varargs and format command.
  54   va_list args;
  55   va_start(args, format);
  56   NSString* command = [[NSString alloc] initWithFormat:format arguments:args];
  57   va_end(args);
  58
  59   NSNumber* callbackKey = [NSNumber numberWithInt:_nextID++];
  60   NSString* taggedCommand = [NSString stringWithFormat:@"%@ -i %@", [command autorelease], callbackKey];
  61
  62   assert(_messageQueue);
  63   [_messageQueue sendMessage:taggedCommand];
  64   return callbackKey;
  65 }
  66
  67 - (NSNumber*)sendCustomCommandWithFormat:(NSString*)format, ... {
  68   // Collect varargs and format command.
  69   va_list args;
  70   va_start(args, format);
  71   NSString* command = [[[NSString alloc] initWithFormat:format arguments:args] autorelease];
  72   va_end(args);
  73
  74   NSNumber* callbackKey = [NSNumber numberWithInt:_nextID++];
  75   NSString* taggedCommand = [command stringByReplacingOccurrencesOfString:@"{txn}"
  76                                                                withString:[callbackKey stringValue]];
  77
  78   [_messageQueue sendMessage:taggedCommand];
  79   return callbackKey;
  80 }
  81
  82 - (NSInteger)transactionIDFromResponse:(NSXMLDocument*)response {
  83   return [[[[response rootElement] attributeForName:@"transaction_id"] stringValue] intValue];
  84 }
  85
  86 - (NSInteger)transactionIDFromCommand:(NSString*)command {
  87   NSRange occurrence = [command rangeOfString:@"-i "];
  88   if (occurrence.location == NSNotFound)
  89     return NSNotFound;
  90   NSString* transaction = [command substringFromIndex:occurrence.location + occurrence.length];
  91   return [transaction intValue];
  92 }
  93
  94 // MessageQueueDelegate ////////////////////////////////////////////////////////
  95
  96 - (void)messageQueue:(MessageQueue*)queue error:(NSError*)error {
  97   NSLog(@"error = %@", error);
  98 }
  99
 100 - (void)messageQueueDidConnect:(MessageQueue*)queue {
 101   [_lock lock];
 102   _nextID = 0;
 103   _lastReadID = 0;
 104   _lastWrittenID = 0;
 105   [_lock unlock];
 106
 107   [_delegate debuggerEngineConnected:self];
 108 }
 109
 110 - (void)messageQueueDidDisconnect:(MessageQueue*)queue {
 111   [_messageQueue release];
 112   _messageQueue = nil;
 113   [_delegate debuggerEngineDisconnected:self];
 114 }
 115
 116 // If the write stream is ready, the delegate controls whether or not the next
 117 // pending message should be sent via the result of this method.
 118 - (BOOL)shouldSendMessage {
 119   [_lock lock];
 120   BOOL r = _lastReadID >= _lastWrittenID;
 121   [_lock unlock];
 122   return r;
 123 }
 124
 125 // Callback for when a message has been sent.
 126 - (void)messageQueue:(MessageQueue*)queue didSendMessage:(NSString*)message
 127 {
 128   NSInteger tag = [self transactionIDFromCommand:message];
 129   [_lock lock];
 130   _lastWrittenID = tag;
 131   [_lock unlock];
 132
 133   LoggingController* logger = [[AppDelegate instance] loggingController];
 134   LogEntry* entry = [LogEntry newSendEntry:message];
 135   entry.lastReadTransactionID = _lastReadID;
 136   entry.lastWrittenTransactionID = _lastWrittenID;
 137   [logger recordEntry:entry];
 138 }
 139
 140 // Callback with the message content when one has been receieved.
 141 - (void)messageQueue:(MessageQueue*)queue didReceiveMessage:(NSString*)message
 142 {
 143   LoggingController* logger = [[AppDelegate instance] loggingController];
 144   LogEntry* entry = [LogEntry newReceiveEntry:message];
 145   entry.lastReadTransactionID = _lastReadID;
 146   entry.lastWrittenTransactionID = _lastWrittenID;
 147   [logger recordEntry:entry];
 148
 149   // Test if we can convert it into an NSXMLDocument.
 150   NSError* error = nil;
 151   NSXMLDocument* xml = [[NSXMLDocument alloc] initWithXMLString:message
 152                                                         options:NSXMLDocumentTidyXML
 153                                                           error:&error];
 154   if (error) {
 155     [self messageQueue:queue error:error];
 156     return;
 157   }
 158
 159   // Validate the transaction.
 160   NSInteger transaction = [self transactionIDFromResponse:xml];
 161   if (transaction < _lastReadID) {
 162     NSLog(@"Transaction #%d is out of date (lastRead = %d). Dropping packet: %@",
 163           transaction, _lastReadID, message);
 164     return;
 165   }
 166   if (transaction != _lastWrittenID) {
 167     NSLog(@"Transaction #%d received out of order. lastRead = %d, lastWritten = %d. Continuing.",
 168           transaction, _lastReadID, _lastWrittenID);
 169   }
 170
 171   _lastReadID = transaction;
 172   entry.lastReadTransactionID = _lastReadID;
 173
 174   [_delegate debuggerEngine:self receivedMessage:xml];
 175 }
 176
 177 @end