Source/NetworkConnection.mm

   1 /*
   2  * MacGDBp
   3  * Copyright (c) 2007 - 2011, 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 "NetworkConnection.h"
  18 #import "NetworkConnectionPrivate.h"
  19
  20 #import <sys/socket.h>
  21 #import <netinet/in.h>
  22
  23 #import "AppDelegate.h"
  24 #import "LoggingController.h"
  25 #include "NetworkCallbackController.h"
  26
  27 // Other Run Loop Callbacks ////////////////////////////////////////////////////
  28
  29 void PerformQuitSignal(void* info)
  30 {
  31   NetworkConnection* obj = (NetworkConnection*)info;
  32   [obj performQuitSignal];
  33 }
  34
  35 ////////////////////////////////////////////////////////////////////////////////
  36
  37 @implementation NetworkConnection
  38
  39 @synthesize port = port_;
  40 @synthesize connected = connected_;
  41 @synthesize delegate = delegate_;
  42
  43 @synthesize socket = socket_;
  44 @synthesize readStream = readStream_;
  45 @synthesize lastReadTransaction = lastReadTransaction_;
  46 @synthesize currentPacket = currentPacket_;
  47 @synthesize writeStream = writeStream_;
  48 @synthesize lastWrittenTransaction = lastWrittenTransaction_;
  49 @synthesize queuedWrites = queuedWrites_;
  50
  51 - (id)initWithPort:(NSUInteger)aPort
  52 {
  53   if (self = [super init])
  54   {
  55     port_ = aPort;
  56   }
  57   return self;
  58 }
  59
  60 - (void)dealloc
  61 {
  62   self.currentPacket = nil;
  63   [super dealloc];
  64 }
  65
  66 /**
  67  * Kicks off the socket on another thread.
  68  */
  69 - (void)connect
  70 {
  71   if (thread_ && !connected_) {
  72     // A thread has been detached but the socket has yet to connect. Do not
  73     // spawn a new thread otherwise multiple threads will be blocked on the same
  74     // socket.
  75     return;
  76   }
  77   [NSThread detachNewThreadSelector:@selector(runNetworkThread) toTarget:self withObject:nil];
  78 }
  79
  80 /**
  81  * Creates, connects to, and schedules a CFSocket.
  82  */
  83 - (void)runNetworkThread
  84 {
  85   NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];
  86
  87   thread_ = [NSThread currentThread];
  88   runLoop_ = [NSRunLoop currentRunLoop];
  89   callbackController_ = new NetworkCallbackController(self);
  90
  91   // Pass ourselves to the callback so we don't have to use ugly globals.
  92   CFSocketContext context = { 0 };
  93   context.info = callbackController_;
  94
  95   // Create the address structure.
  96   struct sockaddr_in address;
  97   memset(&address, 0, sizeof(address));
  98   address.sin_len = sizeof(address);
  99   address.sin_family = AF_INET;
 100   address.sin_port = htons(port_);
 101   address.sin_addr.s_addr = htonl(INADDR_ANY);
 102
 103   // Create the socket signature.
 104   CFSocketSignature signature;
 105   signature.protocolFamily = PF_INET;
 106   signature.socketType = SOCK_STREAM;
 107   signature.protocol = IPPROTO_TCP;
 108   signature.address = (CFDataRef)[NSData dataWithBytes:&address length:sizeof(address)];
 109
 110   do {
 111     socket_ = CFSocketCreateWithSocketSignature(kCFAllocatorDefault,
 112                                                 &signature,  // Socket signature.
 113                                                 kCFSocketAcceptCallBack,  // Callback types.
 114                                                 &NetworkCallbackController::SocketAcceptCallback,  // Callout function pointer.
 115                                                 &context);  // Context to pass to callout.
 116     if (!socket_) {
 117       [self errorEncountered:@"Could not open socket."];
 118       sleep(1);
 119     }
 120   } while (!socket_);
 121
 122   // Allow old, yet-to-be recycled sockets to be reused.
 123   BOOL yes = YES;
 124   setsockopt(CFSocketGetNative(socket_), SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(BOOL));
 125   setsockopt(CFSocketGetNative(socket_), SOL_SOCKET, SO_REUSEPORT, &yes, sizeof(BOOL));
 126
 127   // Schedule the socket on the run loop.
 128   CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, socket_, 0);
 129   CFRunLoopAddSource([runLoop_ getCFRunLoop], source, kCFRunLoopCommonModes);
 130   CFRelease(source);
 131
 132   // Create a source that is used to quit.
 133   CFRunLoopSourceContext quitContext = { 0 };
 134   quitContext.info = self;
 135   quitContext.perform = PerformQuitSignal;
 136   quitSource_ = CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &quitContext);
 137   CFRunLoopAddSource([runLoop_ getCFRunLoop], quitSource_, kCFRunLoopCommonModes);
 138
 139   CFRunLoopRun();
 140
 141   thread_ = nil;
 142   runLoop_ = nil;
 143   delete callbackController_;
 144   callbackController_ = NULL;
 145
 146   CFRunLoopSourceInvalidate(quitSource_);
 147   CFRelease(quitSource_);
 148   quitSource_ = NULL;
 149
 150   [pool release];
 151 }
 152
 153 /**
 154  * Called by SocketWrapper after the connection is successful. This immediately calls
 155  * -[SocketWrapper receive] to clear the way for communication, though the information
 156  * could be useful server information that we don't use right now.
 157  */
 158 - (void)socketDidAccept
 159 {
 160   connected_ = YES;
 161   transactionID = 1;
 162   lastReadTransaction_ = 0;
 163   lastWrittenTransaction_ = 0;
 164   self.queuedWrites = [NSMutableArray array];
 165   writeQueueLock_ = [NSRecursiveLock new];
 166   if ([delegate_ respondsToSelector:@selector(connectionDidAccept:)])
 167     [delegate_ performSelectorOnMainThread:@selector(connectionDidAccept:)
 168                                 withObject:self
 169                              waitUntilDone:NO];
 170 }
 171
 172 /**
 173  * Closes a socket and releases the ref.
 174  */
 175 - (void)close
 176 {
 177   if (thread_) {
 178     [thread_ cancel];
 179   }
 180   if (runLoop_ && quitSource_) {
 181     CFRunLoopSourceSignal(quitSource_);
 182     CFRunLoopWakeUp([runLoop_ getCFRunLoop]);
 183   }
 184 }
 185
 186 /**
 187  * Quits the run loop and stops the thread.
 188  */
 189 - (void)performQuitSignal
 190 {
 191   self.queuedWrites = nil;
 192   connected_ = NO;
 193   [writeQueueLock_ release];
 194
 195   if (runLoop_) {
 196     CFRunLoopStop([runLoop_ getCFRunLoop]);
 197   }
 198
 199   // The socket goes down, so do the streams, which clean themselves up.
 200   if (socket_) {
 201     NSLog(@"invalidating socket");
 202     CFSocketInvalidate(socket_);
 203     CFRelease(socket_);
 204     socket_ = NULL;
 205   }
 206 }
 207
 208 /**
 209  * Notification that the socket disconnected.
 210  */
 211 - (void)socketDisconnected
 212 {
 213   if ([delegate_ respondsToSelector:@selector(connectionDidClose:)])
 214     [delegate_ connectionDidClose:self];
 215 }
 216
 217 /**
 218  * Writes a command into the write stream. If the stream is ready for writing,
 219  * we do so immediately. If not, the command is queued and will be written
 220  * when the stream is ready.
 221  */
 222 - (void)send:(NSString*)command
 223 {
 224   if (lastReadTransaction_ >= lastWrittenTransaction_ && CFWriteStreamCanAcceptBytes(writeStream_)) {
 225     [self performSend:command];
 226   } else {
 227     [writeQueueLock_ lock];
 228     [queuedWrites_ addObject:command];
 229     [writeQueueLock_ unlock];
 230   }
 231   [self sendQueuedWrites];
 232 }
 233
 234 /**
 235  * This will send a command to the debugger engine. It will append the
 236  * transaction ID automatically. It accepts a NSString command along with a
 237  * a variable number of arguments to substitute into the command, a la
 238  * +[NSString stringWithFormat:]. Returns the transaction ID as a NSNumber.
 239  */
 240 - (NSNumber*)sendCommandWithFormat:(NSString*)format, ...
 241 {
 242   // Collect varargs and format command.
 243   va_list args;
 244   va_start(args, format);
 245   NSString* command = [[NSString alloc] initWithFormat:format arguments:args];
 246   va_end(args);
 247
 248   NSNumber* callbackKey = [NSNumber numberWithInt:transactionID++];
 249   NSString* taggedCommand = [NSString stringWithFormat:@"%@ -i %@", [command autorelease], callbackKey];
 250   [self performSelector:@selector(send:)
 251                onThread:thread_
 252              withObject:taggedCommand
 253           waitUntilDone:connected_];
 254
 255   return callbackKey;
 256 }
 257
 258 /**
 259  * Given a file path, this returns a file:// URI and escapes any spaces for the
 260  * debugger engine.
 261  */
 262 - (NSString*)escapedURIPath:(NSString*)path
 263 {
 264   // Custon GDBp paths are fine.
 265   if ([[path substringToIndex:4] isEqualToString:@"gdbp"])
 266     return path;
 267
 268   // Create a temporary URL that will escape all the nasty characters.
 269   NSURL* url = [NSURL fileURLWithPath:path];
 270   NSString* urlString = [url absoluteString];
 271
 272   // Remove the host because this is a file:// URL;
 273   urlString = [urlString stringByReplacingOccurrencesOfString:[url host] withString:@""];
 274
 275   // Escape % for use in printf-style NSString formatters.
 276   urlString = [urlString stringByReplacingOccurrencesOfString:@"%" withString:@"%%"];
 277   return urlString;
 278 }
 279
 280 /**
 281  * Returns the transaction_id from an NSXMLDocument.
 282  */
 283 - (NSInteger)transactionIDFromResponse:(NSXMLDocument*)response
 284 {
 285   return [[[[response rootElement] attributeForName:@"transaction_id"] stringValue] intValue];
 286 }
 287
 288 /**
 289  * Scans a command string for the transaction ID component. If it is not found,
 290  * returns NSNotFound.
 291  */
 292 - (NSInteger)transactionIDFromCommand:(NSString*)command
 293 {
 294   NSRange occurrence = [command rangeOfString:@"-i "];
 295   if (occurrence.location == NSNotFound)
 296     return NSNotFound;
 297   NSString* transaction = [command substringFromIndex:occurrence.location + occurrence.length];
 298   return [transaction intValue];
 299 }
 300
 301 // Private /////////////////////////////////////////////////////////////////////
 302 #pragma mark Private
 303
 304 // Delegate Thread-Safe Wrappers ///////////////////////////////////////////////
 305
 306 /**
 307  * Receives errors from the SocketWrapper and updates the display
 308  */
 309 - (void)errorEncountered:(NSString*)error
 310 {
 311   if (![delegate_ respondsToSelector:@selector(errorEncountered:)])
 312     return;
 313   [delegate_ performSelectorOnMainThread:@selector(errorEncountered:)
 314                               withObject:error
 315                            waitUntilDone:NO];
 316 }
 317
 318 - (LogEntry*)recordSend:(NSString*)command
 319 {
 320   LoggingController* logger = [[AppDelegate instance] loggingController];
 321   LogEntry* entry = [LogEntry newSendEntry:command];
 322   entry.lastReadTransactionID = lastReadTransaction_;
 323   entry.lastWrittenTransactionID = lastWrittenTransaction_;
 324   [logger performSelectorOnMainThread:@selector(recordEntry:)
 325                            withObject:entry
 326                         waitUntilDone:NO];
 327   return [entry autorelease];
 328 }
 329
 330 - (LogEntry*)recordReceive:(NSString*)command
 331 {
 332   LoggingController* logger = [[AppDelegate instance] loggingController];
 333   LogEntry* entry = [LogEntry newReceiveEntry:command];
 334   entry.lastReadTransactionID = lastReadTransaction_;
 335   entry.lastWrittenTransactionID = lastWrittenTransaction_;
 336   [logger performSelectorOnMainThread:@selector(recordEntry:)
 337                            withObject:entry
 338                         waitUntilDone:NO];
 339   return [entry autorelease];
 340 }
 341
 342 // Stream Managers /////////////////////////////////////////////////////////////
 343
 344 /**
 345  * Callback from the CFReadStream that there is data waiting to be read.
 346  */
 347 - (void)readStreamHasData
 348 {
 349   const NSUInteger kBufferSize = 1024;
 350   UInt8 buffer[kBufferSize];
 351   CFIndex bufferOffset = 0;  // Starting point in |buffer| to work with.
 352   CFIndex bytesRead = CFReadStreamRead(readStream_, buffer, kBufferSize);
 353   const char* charBuffer = (const char*)buffer;
 354
 355   // The read loop works by going through the buffer until all the bytes have
 356   // been processed.
 357   while (bufferOffset < bytesRead)
 358   {
 359     // Find the NULL separator, or the end of the string.
 360     NSUInteger partLength = 0;
 361     for (NSUInteger i = bufferOffset; i < bytesRead && charBuffer[i] != '\0'; ++i, ++partLength) ;
 362
 363     // If there is not a current packet, set some state.
 364     if (!self.currentPacket)
 365     {
 366       // Read the message header: the size.  This will be |partLength| bytes.
 367       packetSize_ = atoi(charBuffer + bufferOffset);
 368       currentPacketIndex_ = 0;
 369       self.currentPacket = [NSMutableString stringWithCapacity:packetSize_];
 370       bufferOffset += partLength + 1;  // Pass over the NULL byte.
 371       continue;  // Spin the loop to begin reading actual data.
 372     }
 373
 374     // Substring the byte stream and append it to the packet string.
 375     CFStringRef bufferString = CFStringCreateWithBytes(kCFAllocatorDefault,
 376                                                        buffer + bufferOffset,  // Byte pointer, offset by start index.
 377                                                        partLength,  // Length.
 378                                                        kCFStringEncodingUTF8,
 379                                                        true);
 380     [self.currentPacket appendString:(NSString*)bufferString];
 381     CFRelease(bufferString);
 382
 383     // Advance counters.
 384     currentPacketIndex_ += partLength;
 385     bufferOffset += partLength + 1;
 386
 387     // If this read finished the packet, handle it and reset.
 388     if (currentPacketIndex_ >= packetSize_)
 389     {
 390       [self handlePacket:[[currentPacket_ retain] autorelease]];
 391       self.currentPacket = nil;
 392       packetSize_ = 0;
 393       currentPacketIndex_ = 0;
 394     }
 395   }
 396 }
 397
 398 /**
 399  * Performs the packet handling of a raw string XML packet. From this point on,
 400  * the packets are associated with a transaction and are then dispatched.
 401  */
 402 - (void)handlePacket:(NSString*)packet
 403 {
 404   // Test if we can convert it into an NSXMLDocument.
 405   NSError* error = nil;
 406   NSXMLDocument* xmlTest = [[NSXMLDocument alloc] initWithXMLString:currentPacket_ options:NSXMLDocumentTidyXML error:&error];
 407
 408   // Try to recover if we encountered an error.
 409   if (!xmlTest)
 410   {
 411     // We do not want to starve the write queue, so manually parse out the
 412     // transaction ID.
 413     NSRange location = [currentPacket_ rangeOfString:@"transaction_id"];
 414     if (location.location != NSNotFound)
 415     {
 416       NSUInteger start = location.location + location.length;
 417       NSUInteger end = start;
 418
 419       NSCharacterSet* numericSet = [NSCharacterSet decimalDigitCharacterSet];
 420
 421       // Loop over the characters after the attribute name to extract the ID.
 422       while (end < [currentPacket_ length])
 423       {
 424         unichar c = [currentPacket_ characterAtIndex:end];
 425         if ([numericSet characterIsMember:c])
 426         {
 427           // If this character is numeric, extend the range to substring.
 428           ++end;
 429         }
 430         else
 431         {
 432           if (start == end)
 433           {
 434             // If this character is nonnumeric and we have nothing in the
 435             // range, skip this character.
 436             ++start;
 437             ++end;
 438           }
 439           else
 440           {
 441             // We've moved past the numeric ID so we should stop searching.
 442             break;
 443           }
 444         }
 445       }
 446
 447       // If we were able to extract the transaction ID, update the last read.
 448       NSRange substringRange = NSMakeRange(start, end - start);
 449       NSString* transactionStr = [currentPacket_ substringWithRange:substringRange];
 450       if ([transactionStr length])
 451         lastReadTransaction_ = [transactionStr intValue];
 452     }
 453
 454     // Otherwise, assume +1 and hope it works.
 455     ++lastReadTransaction_;
 456   } else /*if (!reconnect_)*/ {
 457     // See if the transaction can be parsed out.
 458     NSInteger transaction = [self transactionIDFromResponse:xmlTest];
 459     if (transaction < lastReadTransaction_) {
 460       NSLog(@"tx = %d vs %d", transaction, lastReadTransaction_);
 461       NSLog(@"out of date transaction %@", packet);
 462       return;
 463     }
 464
 465     if (transaction != lastWrittenTransaction_)
 466       NSLog(@"txn %d <> %d last written, %d last read", transaction, lastWrittenTransaction_, lastReadTransaction_);
 467
 468     lastReadTransaction_ = transaction;
 469   }
 470
 471   // Log this receive event.
 472   LogEntry* log = [self recordReceive:currentPacket_];
 473   log.error = error;
 474
 475   // Finally, dispatch the handler for this response.
 476   [self handleResponse:[xmlTest autorelease]];
 477 }
 478
 479 - (void)handleResponse:(NSXMLDocument*)response
 480 {
 481   // Check and see if there's an error.
 482   NSArray* error = [[response rootElement] elementsForName:@"error"];
 483   if ([error count] > 0)
 484   {
 485     NSLog(@"Xdebug error: %@", error);
 486     NSString* errorMessage = [[[[error objectAtIndex:0] children] objectAtIndex:0] stringValue];
 487     [self errorEncountered:errorMessage];
 488   }
 489
 490   if ([[[response rootElement] name] isEqualToString:@"init"]) {
 491     connected_ = YES;
 492     [delegate_ performSelectorOnMainThread:@selector(handleInitialResponse:)
 493                                 withObject:response
 494                              waitUntilDone:NO];
 495     return;
 496   }
 497
 498   if ([delegate_ respondsToSelector:@selector(handleResponse:)])
 499     [delegate_ performSelectorOnMainThread:@selector(handleResponse:)
 500                                 withObject:response
 501                              waitUntilDone:NO];
 502
 503   [self sendQueuedWrites];
 504 }
 505
 506 /**
 507  * This performs a blocking send. This should ONLY be called when we know we
 508  * have write access to the stream. We will busy wait in case we don't do a full
 509  * send.
 510  */
 511 - (void)performSend:(NSString*)command
 512 {
 513   // If this is an out-of-date transaction, do not bother sending it.
 514   NSInteger transaction = [self transactionIDFromCommand:command];
 515   if (transaction != NSNotFound && transaction < lastWrittenTransaction_)
 516     return;
 517
 518   BOOL done = NO;
 519
 520   char* string = (char*)[command UTF8String];
 521   int stringLength = strlen(string);
 522
 523   // Busy wait while writing. BAADD. Should background this operation.
 524   while (!done)
 525   {
 526     if (CFWriteStreamCanAcceptBytes(writeStream_))
 527     {
 528       // Include the NULL byte in the string when we write.
 529       int bytesWritten = CFWriteStreamWrite(writeStream_, (UInt8*)string, stringLength + 1);
 530       if (bytesWritten < 0)
 531       {
 532         NSLog(@"write error");
 533       }
 534       // Incomplete write.
 535       else if (bytesWritten < strlen(string))
 536       {
 537         // Adjust the buffer and wait for another chance to write.
 538         stringLength -= bytesWritten;
 539         memmove(string, string + bytesWritten, stringLength);
 540       }
 541       else
 542       {
 543         done = YES;
 544
 545         // We need to scan the string to find the transactionID.
 546         if (transaction == NSNotFound)
 547         {
 548           NSLog(@"sent %@ without a transaction ID", command);
 549           continue;
 550         }
 551         lastWrittenTransaction_ = transaction;
 552       }
 553     }
 554   }
 555
 556   // Log this trancation.
 557   [self recordSend:command];
 558 }
 559
 560 /**
 561  * Checks if there are unsent commands in the |queuedWrites_| queue and sends
 562  * them if it's OK to do so. This will not block.
 563  */
 564 - (void)sendQueuedWrites
 565 {
 566   if (!connected_)
 567     return;
 568
 569   [writeQueueLock_ lock];
 570   if (lastReadTransaction_ >= lastWrittenTransaction_ && [queuedWrites_ count] > 0)
 571   {
 572     NSString* command = [queuedWrites_ objectAtIndex:0];
 573
 574     // We don't want to block because this is called from the main thread.
 575     // |-performSend:| busy waits when the stream is not ready. Bail out
 576     // before we do that becuase busy waiting is BAD.
 577     if (CFWriteStreamCanAcceptBytes(writeStream_))
 578     {
 579       [self performSend:command];
 580       [queuedWrites_ removeObjectAtIndex:0];
 581     }
 582   }
 583   [writeQueueLock_ unlock];
 584 }
 585
 586 @end