Source/DebuggerBackEnd.m

   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 "DebuggerBackEnd.h"
  18
  19 #import "AppDelegate.h"
  20 #import "modp_b64.h"
  21 #import "NSXMLElementAdditions.h"
  22
  23 // GDBpConnection (Private) ////////////////////////////////////////////////////
  24
  25 @interface DebuggerBackEnd ()
  26 @property (readwrite, copy) NSString* status;
  27
  28 - (void)recordCallback:(SEL)callback forTransaction:(NSNumber*)txn;
  29
  30 - (void)updateStatus:(NSXMLDocument*)response;
  31 - (void)debuggerStep:(NSXMLDocument*)response;
  32 - (void)rebuildStack:(NSXMLDocument*)response;
  33 - (void)getStackFrame:(NSXMLDocument*)response;
  34 - (void)setSource:(NSXMLDocument*)response;
  35 - (void)contextsReceived:(NSXMLDocument*)response;
  36 - (void)variablesReceived:(NSXMLDocument*)response;
  37 - (void)propertiesReceived:(NSXMLDocument*)response;
  38 - (void)evalScriptReceived:(NSXMLDocument*)response;
  39
  40 @end
  41
  42 // GDBpConnection //////////////////////////////////////////////////////////////
  43
  44 @implementation DebuggerBackEnd
  45
  46 @synthesize status;
  47 @synthesize attached = attached_;
  48 @synthesize delegate;
  49
  50 /**
  51  * Creates a new DebuggerBackEnd and initializes the socket from the given connection
  52  * paramters.
  53  */
  54 - (id)initWithPort:(NSUInteger)aPort
  55 {
  56   if (self = [super init])
  57   {
  58     stackFrames_ = [[NSMutableDictionary alloc] init];
  59     callbackContext_ = [NSMutableDictionary new];
  60     callTable_ = [NSMutableDictionary new];
  61
  62     [[BreakpointManager sharedManager] setConnection:self];
  63     port_ = aPort;
  64     client_ = [[ProtocolClient alloc] initWithDelegate:self];
  65
  66     attached_ = [[NSUserDefaults standardUserDefaults] boolForKey:@"DebuggerAttached"];
  67
  68     if (self.attached)
  69       [client_ connectOnPort:port_];
  70   }
  71   return self;
  72 }
  73
  74 /**
  75  * Deallocates the object
  76  */
  77 - (void)dealloc
  78 {
  79   [client_ release];
  80   [stackFrames_ release];
  81   [callTable_ release];
  82   [callbackContext_ release];
  83   [super dealloc];
  84 }
  85
  86
  87 // Getters /////////////////////////////////////////////////////////////////////
  88 #pragma mark Getters
  89
  90 /**
  91  * Gets the port number
  92  */
  93 - (NSUInteger)port
  94 {
  95   return port_;
  96 }
  97
  98 /**
  99  * Returns whether or not we have an active connection
 100  */
 101 - (BOOL)isConnected
 102 {
 103   return active_;
 104 }
 105
 106 /**
 107  * Sets the attached state of the debugger. This will open and close the
 108  * connection as appropriate.
 109  */
 110 - (void)setAttached:(BOOL)attached {
 111   if (attached != attached_) {
 112     if (!attached)
 113       [client_ connectOnPort:port_];
 114     else
 115       [client_ disconnect];
 116   }
 117   attached_ = attached;
 118 }
 119
 120 // Commands ////////////////////////////////////////////////////////////////////
 121 #pragma mark Commands
 122
 123 /**
 124  * Tells the debugger to continue running the script. Returns the current stack frame.
 125  */
 126 - (void)run
 127 {
 128   NSNumber* tx = [client_ sendCommandWithFormat:@"run"];
 129   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 130 }
 131
 132 /**
 133  * Tells the debugger to step into the current command.
 134  */
 135 - (void)stepIn
 136 {
 137   NSNumber* tx = [client_ sendCommandWithFormat:@"step_into"];
 138   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 139 }
 140
 141 /**
 142  * Tells the debugger to step out of the current context
 143  */
 144 - (void)stepOut
 145 {
 146   NSNumber* tx = [client_ sendCommandWithFormat:@"step_out"];
 147   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 148 }
 149
 150 /**
 151  * Tells the debugger to step over the current function
 152  */
 153 - (void)stepOver
 154 {
 155   NSNumber* tx = [client_ sendCommandWithFormat:@"step_over"];
 156   [self recordCallback:@selector(debuggerStep:) forTransaction:tx];
 157 }
 158
 159 /**
 160  * Halts execution of the script.
 161  */
 162 - (void)stop
 163 {
 164   [client_ disconnect];
 165   active_ = NO;
 166   self.status = @"Stopped";
 167 }
 168
 169 /**
 170  * Ends the current debugging session.
 171  */
 172 - (void)detach
 173 {
 174   [client_ sendCommandWithFormat:@"detach"];
 175   active_ = NO;
 176   self.status = @"Stopped";
 177 }
 178
 179 /**
 180  * Tells the debugger engine to get a specifc property. This also takes in the NSXMLElement
 181  * that requested it so that the child can be attached.
 182  */
 183 - (NSInteger)getChildrenOfProperty:(VariableNode*)property atDepth:(NSInteger)depth;
 184 {
 185   NSNumber* tx = [client_ sendCommandWithFormat:@"property_get -d %d -n %@", depth, [property fullName]];
 186   [self recordCallback:@selector(propertiesReceived:) forTransaction:tx];
 187   return [tx intValue];
 188 }
 189
 190 - (void)loadStackFrame:(StackFrame*)frame
 191 {
 192   if (frame.loaded)
 193     return;
 194
 195   NSNumber* routingNumber = [NSNumber numberWithInt:frame.routingID];
 196   NSNumber* transaction = nil;
 197
 198   // Get the source code of the file. Escape % in URL chars.
 199   if ([frame.filename length]) {
 200     NSString* escapedFilename = [frame.filename stringByReplacingOccurrencesOfString:@"%" withString:@"%%"];
 201     transaction = [client_ sendCommandWithFormat:@"source -f %@", escapedFilename];
 202     [self recordCallback:@selector(setSource:) forTransaction:transaction];
 203     [callbackContext_ setObject:routingNumber forKey:transaction];
 204   }
 205
 206   // Get the names of all the contexts.
 207   transaction = [client_ sendCommandWithFormat:@"context_names -d %d", frame.index];
 208   [self recordCallback:@selector(contextsReceived:) forTransaction:transaction];
 209   [callbackContext_ setObject:routingNumber forKey:transaction];
 210
 211   // This frame will be fully loaded.
 212   frame.loaded = YES;
 213 }
 214
 215 // Breakpoint Management ///////////////////////////////////////////////////////
 216 #pragma mark Breakpoints
 217
 218 /**
 219  * Send an add breakpoint command
 220  */
 221 - (void)addBreakpoint:(Breakpoint*)bp
 222 {
 223   if (!active_)
 224     return;
 225
 226   NSString* file = [ProtocolClient escapedFilePathURI:[bp transformedPath]];
 227   NSNumber* tx = [client_ sendCommandWithFormat:@"breakpoint_set -t line -f %@ -n %i", file, [bp line]];
 228   [self recordCallback:@selector(breakpointReceived:) forTransaction:tx];
 229   [callbackContext_ setObject:bp forKey:tx];
 230 }
 231
 232 /**
 233  * Removes a breakpoint
 234  */
 235 - (void)removeBreakpoint:(Breakpoint*)bp
 236 {
 237   if (!active_)
 238     return;
 239
 240   [client_ sendCommandWithFormat:@"breakpoint_remove -d %i", [bp debuggerId]];
 241 }
 242
 243 /**
 244  * Sends a string to be evaluated by the engine.
 245  */
 246 - (void)evalScript:(NSString*)str
 247 {
 248   if (!active_)
 249     return;
 250
 251   char* encodedString = malloc(modp_b64_encode_len([str length]));
 252   modp_b64_encode(encodedString, [str UTF8String], [str length]);
 253   NSNumber* tx = [client_ sendCustomCommandWithFormat:@"eval -i {txn} -- %s", encodedString];
 254   free(encodedString);
 255
 256   [self recordCallback:@selector(evalScriptReceived:) forTransaction:tx];
 257 }
 258
 259 // Protocol Client Delegate ////////////////////////////////////////////////////
 260 #pragma mark Protocol Client Delegate
 261
 262 - (void)debuggerEngineConnected:(ProtocolClient*)client
 263 {
 264   active_ = YES;
 265 }
 266
 267 /**
 268  * Called when the connection is finally closed. This will reopen the listening
 269  * socket if the debugger remains attached.
 270  */
 271 - (void)debuggerEngineDisconnected:(ProtocolClient*)client
 272 {
 273   active_ = NO;
 274
 275   if ([delegate respondsToSelector:@selector(debuggerDisconnected)])
 276     [delegate debuggerDisconnected];
 277
 278   if (self.attached)
 279     [client_ connectOnPort:port_];
 280 }
 281
 282 - (void)debuggerEngine:(ProtocolClient*)client receivedMessage:(NSXMLDocument*)message
 283 {
 284   // Check and see if there's an error.
 285   NSArray* error = [[message rootElement] elementsForName:@"error"];
 286   if ([error count] > 0) {
 287     NSLog(@"Xdebug error: %@", error);
 288     NSString* errorMessage = [[[[error objectAtIndex:0] children] objectAtIndex:0] stringValue];
 289     [self errorEncountered:errorMessage];
 290   }
 291
 292   if ([[[message rootElement] name] isEqualToString:@"init"]) {
 293     [self handleInitialResponse:message];
 294     return;
 295   }
 296
 297   [self handleResponse:message];
 298 }
 299
 300 // Specific Response Handlers //////////////////////////////////////////////////
 301 #pragma mark Response Handlers
 302
 303 - (void)errorEncountered:(NSString*)error
 304 {
 305   [delegate errorEncountered:error];
 306 }
 307
 308 /**
 309  * Initial packet received. We've started a brand-new connection to the engine.
 310  */
 311 - (void)handleInitialResponse:(NSXMLDocument*)response
 312 {
 313   if (!self.attached) {
 314     [client_ sendCommandWithFormat:@"detach"];
 315     return;
 316   }
 317
 318   active_ = YES;
 319
 320   // Register any breakpoints that exist offline.
 321   for (Breakpoint* bp in [[BreakpointManager sharedManager] breakpoints])
 322     [self addBreakpoint:bp];
 323
 324   // Load the debugger to make it look active.
 325   [delegate debuggerConnected];
 326
 327   // TODO: update the status.
 328 }
 329
 330 - (void)handleResponse:(NSXMLDocument*)response
 331 {
 332   NSInteger transactionID = [client_ transactionIDFromResponse:response];
 333   NSNumber* key = [NSNumber numberWithInt:transactionID];
 334   NSString* callbackStr = [callTable_ objectForKey:key];
 335   if (callbackStr)
 336   {
 337     SEL callback = NSSelectorFromString(callbackStr);
 338     [self performSelector:callback withObject:response];
 339   }
 340   [callTable_ removeObjectForKey:key];
 341 }
 342
 343 /**
 344  * Receiver for status updates. This just freshens up the UI.
 345  */
 346 - (void)updateStatus:(NSXMLDocument*)response
 347 {
 348   self.status = [[[[response rootElement] attributeForName:@"status"] stringValue] capitalizedString];
 349   active_ = YES;
 350   if (!status || [status isEqualToString:@"Stopped"]) {
 351     [delegate debuggerDisconnected];
 352     active_ = NO;
 353   } else if ([status isEqualToString:@"Stopping"]) {
 354     [client_ sendCommandWithFormat:@"stop"];
 355     active_ = NO;
 356   }
 357 }
 358
 359 /**
 360  * Step in/out/over and run all take this path. We first get the status of the
 361  * debugger and then request fresh stack information.
 362  */
 363 - (void)debuggerStep:(NSXMLDocument*)response
 364 {
 365   [self updateStatus:response];
 366   if (![self isConnected])
 367     return;
 368
 369   // If this is the run command, tell the delegate that a bunch of updates
 370   // are coming. Also remove all existing stack routes and request a new stack.
 371   if ([delegate respondsToSelector:@selector(clobberStack)])
 372     [delegate clobberStack];
 373   [stackFrames_ removeAllObjects];
 374   NSNumber* tx = [client_ sendCommandWithFormat:@"stack_depth"];
 375   [self recordCallback:@selector(rebuildStack:) forTransaction:tx];
 376   stackFirstTransactionID_ = [tx intValue];
 377 }
 378
 379 /**
 380  * We ask for the stack_depth and now we clobber the stack and start rebuilding
 381  * it.
 382  */
 383 - (void)rebuildStack:(NSXMLDocument*)response
 384 {
 385   NSInteger depth = [[[[response rootElement] attributeForName:@"depth"] stringValue] intValue];
 386
 387   if (stackFirstTransactionID_ == [client_ transactionIDFromResponse:response])
 388     stackDepth_ = depth;
 389
 390   // We now need to alloc a bunch of stack frames and get the basic information
 391   // for them.
 392   for (NSInteger i = 0; i < depth; i++)
 393   {
 394     // Use the transaction ID to create a routing path.
 395     NSNumber* routingID = [client_ sendCommandWithFormat:@"stack_get -d %d", i];
 396     [self recordCallback:@selector(getStackFrame:) forTransaction:routingID];
 397     [stackFrames_ setObject:[[StackFrame new] autorelease] forKey:routingID];
 398   }
 399 }
 400
 401 /**
 402  * The initial rebuild of the stack frame. We now have enough to initialize
 403  * a StackFrame object.
 404  */
 405 - (void)getStackFrame:(NSXMLDocument*)response
 406 {
 407   // Get the routing information.
 408   NSInteger routingID = [client_ transactionIDFromResponse:response];
 409   if (routingID < stackFirstTransactionID_)
 410     return;
 411   NSNumber* routingNumber = [NSNumber numberWithInt:routingID];
 412
 413   // Make sure we initialized this frame in our last |-rebuildStack:|.
 414   StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 415   if (!frame)
 416     return;
 417
 418   NSXMLElement* xmlframe = [[[response rootElement] children] objectAtIndex:0];
 419
 420   // Initialize the stack frame.
 421   frame.index = [[[xmlframe attributeForName:@"level"] stringValue] intValue];
 422   frame.filename = [[xmlframe attributeForName:@"filename"] stringValue];
 423   frame.lineNumber = [[[xmlframe attributeForName:@"lineno"] stringValue] intValue];
 424   frame.function = [[xmlframe attributeForName:@"where"] stringValue];
 425   frame.routingID = routingID;
 426
 427   // Only get the complete frame for the first level. The other frames will get
 428   // information loaded lazily when the user clicks on one.
 429   if (frame.index == 0) {
 430     [self loadStackFrame:frame];
 431   }
 432
 433   if ([delegate respondsToSelector:@selector(newStackFrame:)])
 434     [delegate newStackFrame:frame];
 435 }
 436
 437 /**
 438  * Callback for setting the source of a file while rebuilding a specific stack
 439  * frame.
 440  */
 441 - (void)setSource:(NSXMLDocument*)response
 442 {
 443   NSNumber* transaction = [NSNumber numberWithInt:[client_ transactionIDFromResponse:response]];
 444   if ([transaction intValue] < stackFirstTransactionID_)
 445     return;
 446   NSNumber* routingNumber = [callbackContext_ objectForKey:transaction];
 447   if (!routingNumber)
 448     return;
 449
 450   [callbackContext_ removeObjectForKey:transaction];
 451   StackFrame* frame = [stackFrames_ objectForKey:routingNumber];
 452   if (!frame)
 453     return;
 454
 455   frame.source = [[response rootElement] base64DecodedValue];
 456
 457   if ([delegate respondsToSelector:@selector(sourceUpdated:)])
 458     [delegate sourceUpdated:frame];
 459 }
 460
 461 /**
 462  * Enumerates all the contexts of a given stack frame. We then in turn get the
 463  * contents of each one of these contexts.
 464  */
 465 - (void)contextsReceived:(NSXMLDocument*)response
 466 {
 467   // Get the stack frame's routing ID and use it again.
 468   NSNumber* receivedTransaction = [NSNumber numberWithInt:[client_ transactionIDFromResponse:response]];
 469   if ([receivedTransaction intValue] < stackFirstTransactionID_)
 470     return;
 471   NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 472   if (!routingID)
 473     return;
 474
 475   // Get the stack frame by the |routingID|.
 476   StackFrame* frame = [stackFrames_ objectForKey:routingID];
 477
 478   NSXMLElement* contextNames = [response rootElement];
 479   for (NSXMLElement* context in [contextNames children])
 480   {
 481     NSInteger cid = [[[context attributeForName:@"id"] stringValue] intValue];
 482
 483     // Fetch each context's variables.
 484     NSNumber* tx = [client_ sendCommandWithFormat:@"context_get -d %d -c %d", frame.index, cid];
 485     [self recordCallback:@selector(variablesReceived:) forTransaction:tx];
 486     [callbackContext_ setObject:routingID forKey:tx];
 487   }
 488 }
 489
 490 /**
 491  * Receives the variables from the context and attaches them to the stack frame.
 492  */
 493 - (void)variablesReceived:(NSXMLDocument*)response
 494 {
 495   // Get the stack frame's routing ID and use it again.
 496   NSInteger transaction = [client_ transactionIDFromResponse:response];
 497   if (transaction < stackFirstTransactionID_)
 498     return;
 499   NSNumber* receivedTransaction = [NSNumber numberWithInt:transaction];
 500   NSNumber* routingID = [callbackContext_ objectForKey:receivedTransaction];
 501   if (!routingID)
 502     return;
 503
 504   // Get the stack frame by the |routingID|.
 505   StackFrame* frame = [stackFrames_ objectForKey:routingID];
 506
 507   NSMutableArray* variables = [NSMutableArray array];
 508
 509   // Merge the frame's existing variables.
 510   if (frame.variables)
 511     [variables addObjectsFromArray:frame.variables];
 512
 513   // Add these new variables.
 514   NSArray* addVariables = [[response rootElement] children];
 515   if (addVariables) {
 516     for (NSXMLElement* elm in addVariables) {
 517       VariableNode* node = [[VariableNode alloc] initWithXMLNode:elm];
 518       [variables addObject:[node autorelease]];
 519     }
 520   }
 521
 522   frame.variables = variables;
 523 }
 524
 525 /**
 526  * Callback from a |-getProperty:| request.
 527  */
 528 - (void)propertiesReceived:(NSXMLDocument*)response
 529 {
 530   NSInteger transaction = [client_ transactionIDFromResponse:response];
 531
 532   /*
 533    <response>
 534      <property> <!-- this is the one we requested -->
 535        <property ... /> <!-- these are what we want -->
 536      </property>
 537    </repsonse>
 538    */
 539
 540   // Detach all the children so we can insert them into another document.
 541   NSXMLElement* parent = (NSXMLElement*)[[response rootElement] childAtIndex:0];
 542   NSArray* children = [parent children];
 543   [parent setChildren:nil];
 544
 545   [delegate receivedProperties:children forTransaction:transaction];
 546 }
 547
 548 /**
 549  * Callback from a |-evalScript:| request.
 550  */
 551 - (void)evalScriptReceived:(NSXMLDocument*)response
 552 {
 553   NSXMLElement* parent = (NSXMLElement*)[[response rootElement] childAtIndex:0];
 554   NSString* value = [parent base64DecodedValue];
 555   [delegate scriptWasEvaluatedWithResult:value];
 556 }
 557
 558 /**
 559  * Callback for setting a breakpoint.
 560  */
 561 - (void)breakpointReceived:(NSXMLDocument*)response
 562 {
 563   NSNumber* transaction = [NSNumber numberWithInt:[client_ transactionIDFromResponse:response]];
 564   Breakpoint* bp = [callbackContext_ objectForKey:transaction];
 565   if (!bp)
 566     return;
 567
 568   [callbackContext_ removeObjectForKey:callbackContext_];
 569   [bp setDebuggerId:[[[[response rootElement] attributeForName:@"id"] stringValue] intValue]];
 570 }
 571
 572 // Private /////////////////////////////////////////////////////////////////////
 573
 574 - (void)recordCallback:(SEL)callback forTransaction:(NSNumber*)txn
 575 {
 576   [callTable_ setObject:NSStringFromSelector(callback) forKey:txn];
 577 }
 578
 579 @end