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