Source/DebuggerConnection.m

   1 /*
   2  * MacGDBp
   3  * Copyright (c) 2007 - 2010, 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 <sys/socket.h>
  18 #import <netinet/in.h>
  19
  20 #import "DebuggerConnection.h"
  21
  22 #import "AppDelegate.h"
  23 #import "LoggingController.h"
  24
  25 // GDBpConnection (Private) ////////////////////////////////////////////////////
  26
  27 @interface DebuggerConnection ()
  28 @property (readwrite, copy) NSString* status;
  29 @property (assign) CFSocketRef socket;
  30 @property (assign) CFReadStreamRef readStream;
  31 @property NSUInteger lastReadTransaction;
  32 @property (retain) NSMutableString* currentPacket;
  33 @property (assign) CFWriteStreamRef writeStream;
  34 @property NSUInteger lastWrittenTransaction;
  35 @property (retain) NSMutableArray* queuedWrites;
  36
  37 - (void)connect;
  38 - (void)close;
  39 - (void)socketDidAccept;
  40 - (void)socketDisconnected;
  41 - (void)readStreamHasData;
  42 - (void)send:(NSString*)command;
  43 - (void)performSend:(NSString*)command;
  44 - (void)errorEncountered:(NSString*)error;
  45
  46 - (void)handleResponse:(NSXMLDocument*)response;
  47 - (void)initReceived:(NSXMLDocument*)response;
  48 - (void)updateStatus:(NSXMLDocument*)response;
  49 - (void)debuggerStep:(NSXMLDocument*)response;
  50 - (void)rebuildStack:(NSXMLDocument*)response;
  51 - (void)getStackFrame:(NSXMLDocument*)response;
  52 - (void)setSource:(NSXMLDocument*)response;
  53 - (void)contextsReceived:(NSXMLDocument*)response;
  54 - (void)variablesReceived:(NSXMLDocument*)response;
  55 - (void)propertiesReceived:(NSXMLDocument*)response;
  56
  57 - (NSNumber*)sendCommandWithCallback:(SEL)callback format:(NSString*)format, ...;
  58
  59 - (void)sendQueuedWrites;
  60
  61 - (NSString*)escapedURIPath:(NSString*)path;
  62 - (NSInteger)transactionIDFromResponse:(NSXMLDocument*)response;
  63 @end
  64
  65 // CFNetwork Callbacks /////////////////////////////////////////////////////////
  66
  67 void ReadStreamCallback(CFReadStreamRef stream, CFStreamEventType eventType, void* connectionRaw)
  68 {
  69         DebuggerConnection* connection = (DebuggerConnection*)connectionRaw;
  70         switch (eventType)
  71         {
  72                 case kCFStreamEventHasBytesAvailable:
  73                         [connection readStreamHasData];
  74                         break;
  75
  76                 case kCFStreamEventErrorOccurred:
  77                 {
  78                         CFErrorRef error = CFReadStreamCopyError(stream);
  79                         CFReadStreamUnscheduleFromRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
  80                         CFReadStreamClose(stream);
  81                         CFRelease(stream);
  82                         [connection errorEncountered:[[(NSError*)error autorelease] description]];
  83                         break;
  84                 }
  85
  86                 case kCFStreamEventEndEncountered:
  87                         CFReadStreamUnscheduleFromRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
  88                         CFReadStreamClose(stream);
  89                         CFRelease(stream);
  90                         [connection socketDisconnected];
  91                         break;
  92         };
  93 }
  94
  95 void WriteStreamCallback(CFWriteStreamRef stream, CFStreamEventType eventType, void* connectionRaw)
  96 {
  97         DebuggerConnection* connection = (DebuggerConnection*)connectionRaw;
  98         switch (eventType)
  99         {
 100                 case kCFStreamEventCanAcceptBytes:
 101                         [connection sendQueuedWrites];
 102                         break;
 103
 104                 case kCFStreamEventErrorOccurred:
 105                 {
 106                         CFErrorRef error = CFWriteStreamCopyError(stream);
 107                         CFWriteStreamUnscheduleFromRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
 108                         CFWriteStreamClose(stream);
 109                         CFRelease(stream);
 110                         [connection errorEncountered:[[(NSError*)error autorelease] description]];
 111                         break;
 112                 }
 113
 114                 case kCFStreamEventEndEncountered:
 115                         CFWriteStreamUnscheduleFromRunLoop(stream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
 116                         CFWriteStreamClose(stream);
 117                         CFRelease(stream);
 118                         [connection socketDisconnected];
 119                         break;
 120         }
 121 }
 122
 123 void SocketAcceptCallback(CFSocketRef socket,
 124                                                   CFSocketCallBackType callbackType,
 125                                                   CFDataRef address,
 126                                                   const void* data,
 127                                                   void* connectionRaw)
 128 {
 129         assert(callbackType == kCFSocketAcceptCallBack);
 130         NSLog(@"SocketAcceptCallback()");
 131
 132         DebuggerConnection* connection = (DebuggerConnection*)connectionRaw;
 133
 134         CFReadStreamRef readStream;
 135         CFWriteStreamRef writeStream;
 136
 137         // Create the streams on the socket.
 138         CFStreamCreatePairWithSocket(kCFAllocatorDefault,
 139                                                                  *(CFSocketNativeHandle*)data,  // Socket handle.
 140                                                                  &readStream,  // Read stream in-pointer.
 141                                                                  &writeStream);  // Write stream in-pointer.
 142
 143         // Create struct to register callbacks for the stream.
 144         CFStreamClientContext context;
 145         context.version = 0;
 146         context.info = connection;
 147         context.retain = NULL;
 148         context.release = NULL;
 149         context.copyDescription = NULL;
 150
 151         // Set the client of the read stream.
 152         CFOptionFlags readFlags =
 153                 kCFStreamEventOpenCompleted |
 154                 kCFStreamEventHasBytesAvailable |
 155                 kCFStreamEventErrorOccurred |
 156                 kCFStreamEventEndEncountered;
 157         if (CFReadStreamSetClient(readStream, readFlags, ReadStreamCallback, &context))
 158                 // Schedule in run loop to do asynchronous communication with the engine.
 159                 CFReadStreamScheduleWithRunLoop(readStream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
 160         else
 161                 return;
 162
 163         // Open the stream now that it's scheduled on the run loop.
 164         if (!CFReadStreamOpen(readStream))
 165         {
 166                 CFStreamError error = CFReadStreamGetError(readStream);
 167                 NSLog(@"error! %@", error);
 168                 return;
 169         }
 170
 171         // Set the client of the write stream.
 172         CFOptionFlags writeFlags =
 173                 kCFStreamEventOpenCompleted |
 174                 kCFStreamEventCanAcceptBytes |
 175                 kCFStreamEventErrorOccurred |
 176                 kCFStreamEventEndEncountered;
 177         if (CFWriteStreamSetClient(writeStream, writeFlags, WriteStreamCallback, &context))
 178                 // Schedule it in the run loop to receive error information.
 179                 CFWriteStreamScheduleWithRunLoop(writeStream, CFRunLoopGetCurrent(), kCFRunLoopCommonModes);
 180         else
 181                 return;
 182
 183         // Open the write stream.
 184         if (!CFWriteStreamOpen(writeStream))
 185         {
 186                 CFStreamError error = CFWriteStreamGetError(writeStream);
 187                 NSLog(@"error! %@", error);
 188                 return;
 189         }
 190
 191         connection.readStream = readStream;
 192         connection.writeStream = writeStream;
 193         [connection socketDidAccept];
 194 }
 195
 196 // GDBpConnection //////////////////////////////////////////////////////////////
 197
 198 @implementation DebuggerConnection
 199 @synthesize socket = socket_;
 200 @synthesize readStream = readStream_;
 201 @synthesize lastReadTransaction = lastReadTransaction_;
 202 @synthesize currentPacket = currentPacket_;
 203 @synthesize writeStream = writeStream_;
 204 @synthesize lastWrittenTransaction = lastWrittenTransaction_;
 205 @synthesize queuedWrites = queuedWrites_;
 206 @synthesize status;
 207 @synthesize delegate;
 208
 209 /**
 210  * Creates a new DebuggerConnection and initializes the socket from the given connection
 211  * paramters.
 212  */
 213 - (id)initWithPort:(NSUInteger)aPort
 214 {
 215         if (self = [super init])
 216         {
 217                 port = aPort;
 218                 connected = NO;
 219
 220                 [[BreakpointManager sharedManager] setConnection:self];
 221                 [self connect];
 222         }
 223         return self;
 224 }
 225
 226 /**
 227  * Deallocates the object
 228  */
 229 - (void)dealloc
 230 {
 231         [self close];
 232         self.currentPacket = nil;
 233
 234         [super dealloc];
 235 }
 236
 237
 238 // Getters /////////////////////////////////////////////////////////////////////
 239 #pragma mark Getters
 240
 241 /**
 242  * Gets the port number
 243  */
 244 - (NSUInteger)port
 245 {
 246         return port;
 247 }
 248
 249 /**
 250  * Returns the name of the remote host
 251  */
 252 - (NSString*)remoteHost
 253 {
 254         if (!connected)
 255         {
 256                 return @"(DISCONNECTED)";
 257         }
 258         // TODO: Either impl or remove.
 259         return @"";
 260 }
 261
 262 /**
 263  * Returns whether or not we have an active connection
 264  */
 265 - (BOOL)isConnected
 266 {
 267         return connected;
 268 }
 269
 270 // Commands ////////////////////////////////////////////////////////////////////
 271 #pragma mark Commands
 272
 273 /**
 274  * Reestablishes communication with the remote debugger so that a new connection doesn't have to be
 275  * created every time you want to debug a page
 276  */
 277 - (void)reconnect
 278 {
 279         [self close];
 280         self.status = @"Connecting";
 281         [self connect];
 282 }
 283
 284 /**
 285  * Tells the debugger to continue running the script. Returns the current stack frame.
 286  */
 287 - (void)run
 288 {
 289         [self sendCommandWithCallback:@selector(debuggerStep:) format:@"run"];
 290 }
 291
 292 /**
 293  * Tells the debugger to step into the current command.
 294  */
 295 - (void)stepIn
 296 {
 297         [self sendCommandWithCallback:@selector(debuggerStep:) format:@"step_into"];
 298 }
 299
 300 /**
 301  * Tells the debugger to step out of the current context
 302  */
 303 - (void)stepOut
 304 {
 305         [self sendCommandWithCallback:@selector(debuggerStep:) format:@"step_out"];
 306 }
 307
 308 /**
 309  * Tells the debugger to step over the current function
 310  */
 311 - (void)stepOver
 312 {
 313         [self sendCommandWithCallback:@selector(debuggerStep:) format:@"step_over"];
 314 }
 315
 316 /**
 317  * Tells the debugger engine to get a specifc property. This also takes in the NSXMLElement
 318  * that requested it so that the child can be attached.
 319  */
 320 - (NSInteger)getProperty:(NSString*)property
 321 {
 322         [self sendCommandWithCallback:@selector(propertiesReceived:) format:@"property_get -n \"%@\"", property];
 323 }
 324
 325 // Breakpoint Management ///////////////////////////////////////////////////////
 326 #pragma mark Breakpoints
 327
 328 /**
 329  * Send an add breakpoint command
 330  */
 331 - (void)addBreakpoint:(Breakpoint*)bp
 332 {
 333         if (!connected)
 334                 return;
 335
 336         NSString* file = [self escapedURIPath:[bp transformedPath]];
 337         NSNumber* transaction = [self sendCommandWithCallback:@selector(breakpointReceived:)
 338                                                                                                    format:@"breakpoint_set -t line -f %@ -n %i", file, [bp line]];
 339         [callbackContext_ setObject:bp forKey:transaction];
 340 }
 341
 342 /**
 343  * Removes a breakpoint
 344  */
 345 - (void)removeBreakpoint:(Breakpoint*)bp
 346 {
 347         if (!connected)
 348         {
 349                 return;
 350         }
 351
 352         [self sendCommandWithCallback:nil format:@"breakpoint_remove -d %i", [bp debuggerId]];
 353 }
 354
 355
 356 // Socket and Stream Callbacks /////////////////////////////////////////////////
 357 #pragma mark Callbacks
 358
 359 /**
 360  * Called by SocketWrapper after the connection is successful. This immediately calls
 361  * -[SocketWrapper receive] to clear the way for communication, though the information
 362  * could be useful server information that we don't use right now.
 363  */
 364 - (void)socketDidAccept
 365 {
 366         connected = YES;
 367         transactionID = 1;
 368         stackFrames_ = [[NSMutableDictionary alloc] init];
 369         self.queuedWrites = [NSMutableArray array];
 370         writeQueueLock_ = [NSRecursiveLock new];
 371         callTable_ = [NSMutableDictionary new];
 372         callbackContext_ = [NSMutableDictionary new];
 373 }
 374
 375 /**
 376  * Receives errors from the SocketWrapper and updates the display
 377  */
 378 - (void)errorEncountered:(NSString*)error
 379 {
 380         [delegate errorEncountered:error];
 381 }
 382
 383 /**
 384  * Creates, connects to, and schedules a CFSocket.
 385  */
 386 - (void)connect
 387 {
 388         // Pass ourselves to the callback so we don't have to use ugly globals.
 389         CFSocketContext context;
 390         context.version = 0;
 391         context.info = self;
 392         context.retain = NULL;
 393         context.release = NULL;
 394         context.copyDescription = NULL;
 395
 396         // Create the address structure.
 397         struct sockaddr_in address;
 398         memset(&address, 0, sizeof(address));
 399         address.sin_len = sizeof(address);
 400         address.sin_family = AF_INET;
 401         address.sin_port = htons(port);
 402         address.sin_addr.s_addr = htonl(INADDR_ANY);
 403
 404         // Create the socket signature.
 405         CFSocketSignature signature;
 406         signature.protocolFamily = PF_INET;
 407         signature.socketType = SOCK_STREAM;
 408         signature.protocol = IPPROTO_TCP;
 409         signature.address = (CFDataRef)[NSData dataWithBytes:&address length:sizeof(address)];
 410
 411         socket_ = CFSocketCreateWithSocketSignature(kCFAllocatorDefault,
 412                                                                                                 &signature,  // Socket signature.
 413                                                                                                 kCFSocketAcceptCallBack,  // Callback types.
 414                                                                                                 SocketAcceptCallback,  // Callout function pointer.
 415                                                                                                 &context);  // Context to pass to callout.
 416         if (!socket_)
 417         {
 418                 [self errorEncountered:@"Could not open socket."];
 419                 return;
 420         }
 421
 422         // Allow old, yet-to-be recycled sockets to be reused.
 423         BOOL yes = YES;
 424         setsockopt(CFSocketGetNative(socket_), SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(BOOL));
 425
 426         // Schedule the socket on the run loop.
 427         CFRunLoopSourceRef source = CFSocketCreateRunLoopSource(kCFAllocatorDefault, socket_, 0);
 428         CFRunLoopAddSource(CFRunLoopGetCurrent(), source, kCFRunLoopCommonModes);
 429         CFRelease(source);
 430
 431         self.status = @"Connecting";
 432 }
 433
 434 /**
 435  * Closes a socket and releases the ref.
 436  */
 437 - (void)close
 438 {
 439         // The socket goes down, so do the streams, which clean themselves up.
 440         CFSocketInvalidate(socket_);
 441         CFRelease(socket_);
 442         [stackFrames_ release];
 443         self.queuedWrites = nil;
 444         [writeQueueLock_ release];
 445         [callTable_ release];
 446         [callbackContext_ release];
 447 }
 448
 449 /**
 450  * Notification that the socket disconnected.
 451  */
 452 - (void)socketDisconnected
 453 {
 454         [self close];
 455         [delegate debuggerDisconnected];
 456 }
 457
 458 /**
 459  * Callback from the CFReadStream that there is data waiting to be read.
 460  */
 461 - (void)readStreamHasData
 462 {
 463         UInt8 buffer[1024];
 464         CFIndex bytesRead = CFReadStreamRead(readStream_, buffer, 1024);
 465         const char* charBuffer = (const char*)buffer;
 466
 467         // We haven't finished reading a packet, so just read more data in.
 468         if (currentPacketIndex_ < packetSize_)
 469         {
 470                 currentPacketIndex_ += bytesRead;
 471                 CFStringRef bufferString = CFStringCreateWithBytes(kCFAllocatorDefault,
 472                                                                                                                    buffer,
 473                                                                                                                    bytesRead,
 474                                                                                                                    kCFStringEncodingUTF8,
 475                                                                                                                    true);
 476                 [self.currentPacket appendString:(NSString*)bufferString];
 477                 CFRelease(bufferString);
 478         }
 479         // Time to read a new packet.
 480         else
 481         {
 482                 // Read the message header: the size.
 483                 packetSize_ = atoi(charBuffer);
 484                 currentPacketIndex_ = bytesRead - strlen(charBuffer);
 485                 CFStringRef bufferString = CFStringCreateWithBytes(kCFAllocatorDefault,
 486                                                                                                                    buffer + strlen(charBuffer) + 1,
 487                                                                                                                    bytesRead - strlen(charBuffer) - 1,
 488                                                                                                                    kCFStringEncodingUTF8,
 489                                                                                                                    true);
 490                 self.currentPacket = [NSMutableString stringWithString:(NSString*)bufferString];
 491                 CFRelease(bufferString);
 492         }
 493
 494         // We have finished reading the packet.
 495         if (currentPacketIndex_ >= packetSize_)
 496         {
 497                 packetSize_ = 0;
 498                 currentPacketIndex_ = 0;
 499
 500                 // Test if we can convert it into an NSXMLDocument.
 501                 NSError* error = nil;
 502                 NSXMLDocument* xmlTest = [[NSXMLDocument alloc] initWithXMLString:currentPacket_ options:NSXMLDocumentTidyXML error:&error];
 503
 504                 // Log this receive event.
 505                 LoggingController* logger = [(AppDelegate*)[NSApp delegate] loggingController];
 506                 LogEntry* log = [logger recordReceive:currentPacket_];
 507                 log.error = error;
 508                 log.lastWrittenTransactionID = lastWrittenTransaction_;
 509                 log.lastReadTransactionID = lastReadTransaction_;
 510
 511                 // Try to recover if we encountered an error.
 512                 if (error)
 513                 {
 514                         NSLog(@"Could not parse XML? --- %@", error);
 515                         NSLog(@"Error UserInfo: %@", [error userInfo]);
 516                         NSLog(@"This is the XML Document: %@", currentPacket_);
 517
 518                         // We do not want to starve the write queue, so manually parse out the
 519                         // transaction ID.
 520                         NSRange location = [currentPacket_ rangeOfString:@"transaction_id"];
 521                         if (location.location != NSNotFound)
 522                         {
 523                                 NSUInteger start = location.location + location.length;
 524                                 NSUInteger end = start;
 525
 526                                 NSCharacterSet* numericSet = [NSCharacterSet decimalDigitCharacterSet];
 527
 528                                 // Loop over the characters after the attribute name to extract the ID.
 529                                 while (end < [currentPacket_ length])
 530                                 {
 531                                         unichar c = [currentPacket_ characterAtIndex:end];
 532                                         if ([numericSet characterIsMember:c])
 533                                         {
 534                                                 // If this character is numeric, extend the range to substring.
 535                                                 ++end;
 536                                         }
 537                                         else
 538                                         {
 539                                                 if (start == end)
 540                                                 {
 541                                                         // If this character is nonnumeric and we have nothing in the
 542                                                         // range, skip this character.
 543                                                         ++start;
 544                                                         ++end;
 545                                                 }
 546                                                 else
 547                                                 {
 548                                                         // We've moved past the numeric ID so we should stop searching.
 549                                                         break;
 550                                                 }
 551                                         }
 552                                 }
 553
 554                                 // If we were able to extract the transaction ID, update the last read.
 555                                 NSRange substringRange = NSMakeRange(start, end - start);
 556                                 NSString* transaction = [currentPacket_ substringWithRange:substringRange];
 557                                 if ([transaction length])
 558                                 {
 559                                         lastReadTransaction_ = [transaction intValue];
 560                                         return;
 561                                 }
 562                         }
 563
 564                         // Otherwise, assume +1 and hope it works.
 565                         ++lastReadTransaction_;
 566                         return;
 567                 }
 568                 [self handleResponse:[xmlTest autorelease]];
 569         }
 570 }
 571
 572 /**
 573  * Writes a command into the write stream. If the stream is ready for writing,
 574  * we do so immediately. If not, the command is queued and will be written
 575  * when the stream is ready.
 576  */
 577 - (void)send:(NSString*)command
 578 {
 579         if (lastReadTransaction_ >= lastWrittenTransaction_ && CFWriteStreamCanAcceptBytes(writeStream_))
 580                 [self performSend:command];
 581         else
 582                 [queuedWrites_ addObject:command];
 583 }
 584
 585 /**
 586  * This performs a blocking send. This should ONLY be called when we know we
 587  * have write access to the stream. We will busy wait in case we don't do a full
 588  * send.
 589  */
 590 - (void)performSend:(NSString*)command
 591 {
 592         BOOL done = NO;
 593
 594         char* string = (char*)[command UTF8String];
 595         int stringLength = strlen(string);
 596
 597         // Log this trancation.
 598         LoggingController* logger = [(AppDelegate*)[NSApp delegate] loggingController];
 599         LogEntry* log = [logger recordSend:command];
 600         log.lastWrittenTransactionID = lastWrittenTransaction_;
 601         log.lastReadTransactionID = lastReadTransaction_;
 602
 603         // Busy wait while writing. BAADD. Should background this operation.
 604         while (!done)
 605         {
 606                 if (CFWriteStreamCanAcceptBytes(writeStream_))
 607                 {
 608                         // Include the NULL byte in the string when we write.
 609                         int bytesWritten = CFWriteStreamWrite(writeStream_, (UInt8*)string, stringLength + 1);
 610                         if (bytesWritten < 0)
 611                         {
 612                                 NSLog(@"write error");
 613                         }
 614                         // Incomplete write.
 615                         else if (bytesWritten < strlen(string))
 616                         {
 617                                 // Adjust the buffer and wait for another chance to write.
 618                                 stringLength -= bytesWritten;
 619                                 memmove(string, string + bytesWritten, stringLength);
 620                         }
 621                         else
 622                         {
 623                                 done = YES;
 624
 625                                 // We need to scan the string to find the transactionID.
 626                                 NSRange occurrence = [command rangeOfString:@"-i "];
 627                                 if (occurrence.location == NSNotFound)
 628                                 {
 629                                         NSLog(@"sent %@ without a transaction ID", command);
 630                                         continue;
 631                                 }
 632                                 NSString* transaction = [command substringFromIndex:occurrence.location + occurrence.length];
 633                                 lastWrittenTransaction_ = [transaction intValue];
 634                         }
 635                 }
 636         }
 637 }
 638
 639 - (void)handleResponse:(NSXMLDocument*)response
 640 {
 641         // Check and see if there's an error.
 642         NSArray* error = [[response rootElement] elementsForName:@"error"];
 643         if ([error count] > 0)
 644         {
 645                 NSLog(@"Xdebug error: %@", error);
 646                 [delegate errorEncountered:[[[[error objectAtIndex:0] children] objectAtIndex:0] stringValue]];
 647         }
 648
 649         // Get the name of the command from the engine's response.
 650         NSInteger transaction = [self transactionIDFromResponse:response];
 651         if (transaction < lastReadTransaction_)
 652                 NSLog(@"out of date transaction %@", response);
 653
 654         if (transaction != lastWrittenTransaction_)
 655                 NSLog(@"txn doesn't match last written %@", response);
 656
 657         lastReadTransaction_ = transaction;
 658
 659         if ([[[response rootElement] name] isEqualToString:@"init"])
 660         {
 661                 [self initReceived:response];
 662                 return;
 663         }
 664
 665         NSString* callbackStr = [callTable_ objectForKey:[NSNumber numberWithInt:lastReadTransaction_]];
 666         if (callbackStr)
 667         {
 668                 SEL callback = NSSelectorFromString(callbackStr);
 669                 [self performSelector:callback withObject:response];
 670         }
 671
 672         [self sendQueuedWrites];
 673 }
 674
 675 // Specific Response Handlers //////////////////////////////////////////////////
 676 #pragma mark Response Handlers
 677
 678 /**
 679  * Initial packet received. We've started a brand-new connection to the engine.
 680  */
 681 - (void)initReceived:(NSXMLDocument*)response
 682 {
 683         // Register any breakpoints that exist offline.
 684         for (Breakpoint* bp in [[BreakpointManager sharedManager] breakpoints])
 685                 [self addBreakpoint:bp];
 686
 687         // Load the debugger to make it look active.
 688         [delegate debuggerConnected];
 689
 690         // TODO: update the status.
 691 }
 692
 693 /**
 694  * Receiver for status updates. This just freshens up the UI.
 695  */
 696 - (void)updateStatus:(NSXMLDocument*)response
 697 {
 698         self.status = [[[[response rootElement] attributeForName:@"status"] stringValue] capitalizedString];
 699         if (status == nil || [status isEqualToString:@"Stopped"] || [status isEqualToString:@"Stopping"])
 700         {
 701                 connected = NO;
 702                 [self close];
 703                 [delegate debuggerDisconnected];
 704
 705                 self.status = @"Stopped";
 706         }
 707 }
 708
 709 /**
 710  * Step in/out/over and run all take this path. We first get the status of the
 711  * debugger and then request fresh stack information.
 712  */
 713 - (void)debuggerStep:(NSXMLDocument*)response
 714 {
 715         [self updateStatus:response];
 716         if (!connected)
 717                 return;
 718
 719         // If this is the run command, tell the delegate that a bunch of updates
 720         // are coming. Also remove all existing stack routes and request a new stack.
 721         // TODO: figure out if we can not clobber the stack every time.
 722         NSString* command = [[[response rootElement] attributeForName:@"command"] stringValue];
 723         if (YES || [command isEqualToString:@"run"])
 724         {
 725                 if ([delegate respondsToSelector:@selector(clobberStack)])
 726                         [delegate clobberStack];
 727                 [stackFrames_ removeAllObjects];
 728                 stackFirstTransactionID_ = [[self sendCommandWithCallback:@selector(rebuildStack:) format:@"stack_depth"] intValue];
 729         }
 730 }
 731
 732 /**
 733  * We ask for the stack_depth and now we clobber the stack and start rebuilding
 734  * it.
 735  */
 736 - (void)rebuildStack:(NSXMLDocument*)response
 737 {
 738         NSInteger depth = [[[[response rootElement] attributeForName:@"depth"] stringValue] intValue];
 739
 740         if (stackFirstTransactionID_ == [self transactionIDFromResponse:response])
 741                 stackDepth_ = depth;
 742
 743         // We now need to alloc a bunch of stack frames and get the basic information
 744         // for them.
 745         for (NSInteger i = 0; i < depth; i++)
 746         {
 747                 // Use the transaction ID to create a routing path.
 748                 NSNumber* routingID = [self sendCommandWithCallback:@selector(getStackFrame:) format:@"stack_get -d %d", i];
 749                 [stackFrames_ setObject:[StackFrame alloc] forKey:routingID];
 750         }
 751 }
 752
 753 /**
 754  * The initial rebuild of the stack frame. We now have enough to initialize
 755  * a StackFrame object.
 756  */
 757 - (void)getStackFrame:(NSXMLDocument*)response
 758 {
 759         // Get the routing information.
 760         NSInteger routingID = [self transactionIDFromResponse:response];
 761         if (routingID < stackFirstTransactionID_)
 762                 return;
 763         NSNumber* routingNumber = [NSNumber numberWithInt:routingID];
 764
 765         // Make sure we initialized this frame in our last |-rebuildStack:|.
 766         StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 767         if (!frame)
 768                 return;
 769
 770         NSXMLElement* xmlframe = [[[response rootElement] children] objectAtIndex:0];
 771
 772         // Initialize the stack frame.
 773         [frame initWithIndex:[[[xmlframe attributeForName:@"level"] stringValue] intValue]
 774                         withFilename:[[xmlframe attributeForName:@"filename"] stringValue]
 775                           withSource:nil
 776                                   atLine:[[[xmlframe attributeForName:@"lineno"] stringValue] intValue]
 777                           inFunction:[[xmlframe attributeForName:@"where"] stringValue]
 778                    withVariables:nil];
 779
 780         // Get the source code of the file. Escape % in URL chars.
 781         NSString* escapedFilename = [frame.filename stringByReplacingOccurrencesOfString:@"%" withString:@"%%"];
 782         NSNumber* transaction = [self sendCommandWithCallback:@selector(setSource:) format:@"source -f %@", escapedFilename];
 783         [callbackContext_ setObject:routingNumber forKey:transaction];
 784
 785         // Get the names of all the contexts.
 786         transaction = [self sendCommandWithCallback:@selector(contextsReceived:) format:@"context_names -d %d", frame.index];
 787         [callbackContext_ setObject:routingNumber forKey:transaction];
 788
 789         if ([delegate respondsToSelector:@selector(newStackFrame:)])
 790                 [delegate newStackFrame:frame];
 791 }
 792
 793 /**
 794  * Callback for setting the source of a file while rebuilding a specific stack
 795  * frame.
 796  */
 797 - (void)setSource:(NSXMLDocument*)response
 798 {
 799         NSNumber* transaction = [NSNumber numberWithInt:[self transactionIDFromResponse:response]];
 800         if ([transaction intValue] < stackFirstTransactionID_)
 801                 return;
 802         NSNumber* routingNumber = [callbackContext_ objectForKey:transaction];
 803         if (!routingNumber)
 804                 return;
 805
 806         [callbackContext_ removeObjectForKey:transaction];
 807         StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 808         if (!frame)
 809                 return;
 810
 811         frame.source = [[response rootElement] value];
 812
 813         if ([delegate respondsToSelector:@selector(sourceUpdated:)])
 814                 [delegate sourceUpdated:frame];
 815 }
 816
 817 /**
 818  * Enumerates all the contexts of a given stack frame. We then in turn get the
 819  * contents of each one of these contexts.
 820  */
 821 - (void)contextsReceived:(NSXMLDocument*)response
 822 {
 823         // Get the stack frame's routing ID and use it again.
 824         NSNumber* receivedTransaction = [NSNumber numberWithInt:[self transactionIDFromResponse:response]];
 825         if ([receivedTransaction intValue] < stackFirstTransactionID_)
 826                 return;
 827         NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 828         if (!routingID)
 829                 return;
 830
 831         // Get the stack frame by the |routingID|.
 832         StackFrame* frame = [stackFrames_ objectForKey:routingID];
 833
 834         NSXMLElement* contextNames = [response rootElement];
 835         for (NSXMLElement* context in [contextNames children])
 836         {
 837                 NSInteger cid = [[[context attributeForName:@"id"] stringValue] intValue];
 838
 839                 // Fetch each context's variables.
 840                 NSNumber* transaction = [self sendCommandWithCallback:@selector(variablesReceived:)
 841                                                                                                            format:@"context_get -d %d -c %d", frame.index, cid];
 842                 [callbackContext_ setObject:routingID forKey:transaction];
 843         }
 844 }
 845
 846 /**
 847  * Receives the variables from the context and attaches them to the stack frame.
 848  */
 849 - (void)variablesReceived:(NSXMLDocument*)response
 850 {
 851         // Get the stack frame's routing ID and use it again.
 852         NSInteger transaction = [self transactionIDFromResponse:response];
 853         if (transaction < stackFirstTransactionID_)
 854                 return;
 855         NSNumber* receivedTransaction = [NSNumber numberWithInt:transaction];
 856         NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 857         if (!routingID)
 858                 return;
 859
 860         // Get the stack frame by the |routingID|.
 861         StackFrame* frame = [stackFrames_ objectForKey:routingID];
 862
 863         NSMutableArray* variables = [NSMutableArray array];
 864
 865         // Merge the frame's existing variables.
 866         if (frame.variables)
 867                 [variables addObjectsFromArray:frame.variables];
 868
 869         // Add these new variables.
 870         NSArray* addVariables = [[response rootElement] children];
 871         if (addVariables)
 872                 [variables addObjectsFromArray:addVariables];
 873
 874         frame.variables = variables;
 875 }
 876
 877 /**
 878  * Callback from a |-getProperty:| request.
 879  */
 880 - (void)propertiesReceived:(NSXMLDocument*)response
 881 {
 882         NSInteger transaction = [self transactionIDFromResponse:response];
 883
 884         /*
 885          <response>
 886                  <property> <!-- this is the one we requested -->
 887                          <property ... /> <!-- these are what we want -->
 888                  </property>
 889          </repsonse>
 890          */
 891
 892         // Detach all the children so we can insert them into another document.
 893         NSXMLElement* parent = (NSXMLElement*)[[response rootElement] childAtIndex:0];
 894         NSArray* children = [parent children];
 895         [parent setChildren:nil];
 896
 897         [delegate receivedProperties:children forTransaction:transaction];
 898 }
 899
 900 /**
 901  * Callback for setting a breakpoint.
 902  */
 903 - (void)breakpointReceived:(NSXMLDocument*)response
 904 {
 905         NSNumber* transaction = [NSNumber numberWithInt:[self transactionIDFromResponse:response]];
 906         Breakpoint* bp = [callbackContext_ objectForKey:transaction];
 907         if (!bp)
 908                 return;
 909
 910         [callbackContext_ removeObjectForKey:callbackContext_];
 911         [bp setDebuggerId:[[[[response rootElement] attributeForName:@"id"] stringValue] intValue]];
 912 }
 913
 914 #pragma mark Private
 915
 916 /**
 917  * This will send a command to the debugger engine. It will append the
 918  * transaction ID automatically. It accepts a NSString command along with a
 919  * a variable number of arguments to substitute into the command, a la
 920  * +[NSString stringWithFormat:]. Returns the transaction ID as a NSNumber.
 921  */
 922 - (NSNumber*)sendCommandWithCallback:(SEL)callback format:(NSString*)format, ...
 923 {
 924         // Collect varargs and format command.
 925         va_list args;
 926         va_start(args, format);
 927         NSString* command = [[NSString alloc] initWithFormat:format arguments:args];
 928         va_end(args);
 929
 930         NSNumber* callbackKey = [NSNumber numberWithInt:transactionID++];
 931         if (callback)
 932                 [callTable_ setObject:NSStringFromSelector(callback) forKey:callbackKey];
 933
 934         [self send:[NSString stringWithFormat:@"%@ -i %@", [command autorelease], callbackKey]];
 935
 936         return callbackKey;
 937 }
 938
 939 /**
 940  * Checks if there are unsent commands in the |queuedWrites_| queue and sends
 941  * them if it's OK to do so. This will not block.
 942  */
 943 - (void)sendQueuedWrites
 944 {
 945         if (!connected)
 946                 return;
 947
 948         [writeQueueLock_ lock];
 949         if (lastReadTransaction_ >= lastWrittenTransaction_ && [queuedWrites_ count] > 0)
 950         {
 951                 NSString* command = [queuedWrites_ objectAtIndex:0];
 952
 953                 // We don't want to block because this is called from the main thread.
 954                 // |-performSend:| busy waits when the stream is not ready. Bail out
 955                 // before we do that becuase busy waiting is BAD.
 956                 if (CFWriteStreamCanAcceptBytes(writeStream_))
 957                 {
 958                         [self performSend:command];
 959                         [queuedWrites_ removeObjectAtIndex:0];
 960                 }
 961         }
 962         [writeQueueLock_ unlock];
 963 }
 964
 965 /**
 966  * Given a file path, this returns a file:// URI and escapes any spaces for the
 967  * debugger engine.
 968  */
 969 - (NSString*)escapedURIPath:(NSString*)path
 970 {
 971         // Custon GDBp paths are fine.
 972         if ([[path substringToIndex:4] isEqualToString:@"gdbp"])
 973                 return path;
 974
 975         // Create a temporary URL that will escape all the nasty characters.
 976         NSURL* url = [NSURL fileURLWithPath:path];
 977         NSString* urlString = [url absoluteString];
 978
 979         // Remove the host because this is a file:// URL;
 980         urlString = [urlString stringByReplacingOccurrencesOfString:[url host] withString:@""];
 981
 982         // Escape % for use in printf-style NSString formatters.
 983         urlString = [urlString stringByReplacingOccurrencesOfString:@"%" withString:@"%%"];
 984         return urlString;
 985 }
 986
 987 /**
 988  * Returns the transaction_id from an NSXMLDocument.
 989  */
 990 - (NSInteger)transactionIDFromResponse:(NSXMLDocument*)response
 991 {
 992         return [[[[response rootElement] attributeForName:@"transaction_id"] stringValue] intValue];
 993 }
 994
 995 @end