Session 412 - Debugging with Xcode

Transcript

1. These are confidential sessions—please refrain from streaming, blogging, or taking pictures Session 412 Debugging in Xcode Ken Orr Xcode Debugger UI Manager
4. Control Flow Correctness
5. Breakpoints Variables
6. Breakpoints and Breakpoint Actions
8. NSLog(@"%ld", foo);
10. Creating and Deleting Breakpoints
11. Creating and Deleting Breakpoints
12. Creating and Deleting Breakpoints ⌘\ Add Or Remove Breakpoint At Current Line
13. Creating and Deleting Breakpoints
14. Managing Your Breakpoints
15. Managing Your Breakpoints
16. Managing Your Breakpoints ⌘6 Breakpoint Navigator
17. Managing Your Breakpoints
18. Managing Your Breakpoints Change a Breakpoint Group Control-click a breakpoint to move it to a different group
19. Managing Your Breakpoints
20. Managing Your Breakpoints Project Breakpoint Group Contains breakpoints that belong to the listed project
21. Managing Your Breakpoints Project Breakpoint Group Contains breakpoints that belong to the listed project
22. Managing Your Breakpoints
23. Managing Your Breakpoints Shared Breakpoint Group Shared breakpoints are available to all users who open the project
24. Managing Your Breakpoints
25. Managing Your Breakpoints
26. Managing Your Breakpoints User Breakpoint Group User breakpoints are available from all of your projects and workspaces
27. Exception and Symbolic Breakpoints
28. Exception and Symbolic Breakpoints Add Breakpoint Allows you to add an exception or symbolic breakpoint
29. Exception and Symbolic Breakpoints Add Breakpoint Allows you to add an exception or symbolic breakpoint
30. Exception and Symbolic Breakpoints
31. Exception and Symbolic Breakpoints Type of Exception Breakpoint Allows you to stop on all exceptions, Objective-C exceptions, or C++ exceptions
32. Exception and Symbolic Breakpoints When to Break Allows you to specify whether you want to break on catch or throw
33. Exception and Symbolic Breakpoints
34. Exception and Symbolic Breakpoints Symbol Name Execution will pause when a symbol with this name is called
35. Exception and Symbolic Breakpoints Module Name Lets you restrict what libraries with the specified symbol name should result in a pause
36. Editing Breakpoints
37. Editing Breakpoints Edit Breakpoint ⌥⌘
38. Editing Breakpoints Condition to Evaluate An expression to evaluate in order to determine if the breakpoint should be stopped at
39. Editing Breakpoints Ignore Count The number of times to ignore the breakpoint before stopping
40. Editing Breakpoints Automatically Continue Continues program execution after all of the breakpoint’s actions have completed
41. Breakpoint Actions
42. Breakpoint Actions
43. Breakpoint Actions
44. Breakpoint Actions
45. Breakpoint Actions
46. Debugger Command Breakpoint Action
47. Debugger Command Breakpoint Action po myVariable
48. Debugger Command Breakpoint Action po myVariable expr (void)NSLog(@“%f“, myVariable)
49. Debugger Command Breakpoint Action po myVariable breakpoint set -f SKTWindowController.m -l 100 expr (void)NSLog(@“%f“, myVariable)
50. Log Message Breakpoint Action
51. Log Message Breakpoint Action myVariable = @myVariable@, hit %H times
52. Shell Command Breakpoint Action
53. Shell Command Breakpoint Action screencapture Command: /tmp/screenShot.png Arguments:
54. Sound Breakpoint Action
55. Sound Breakpoint Action ~/Library/Sounds Sounds put in your home directory show up in Xcode
56. AppleScript Breakpoint Action
57. AppleScript Breakpoint Action tell application "Mail" set myMessage to make new outgoing message with properties {visible:false, subject:"Test Failed", content:"The test failed"} tell myMessage make new to recipient at end of to recipients with properties {name:"Ken Orr", address:"orr@apple.com"} myMessage send end tell end tell
58. Demo Breakpoints and breakpoint actions Alex Raftis Xcode Debugger UI Engineer
59. The Variables View
60. Viewing Your Variables
61. Viewing Your Variables
62. Viewing Your Variables Viewing Mode Auto - variables around the line of code you’re paused at Local - all variables in local scope All - all variables including globals and registers
63. Viewing Your Variables Variable Kind Local Variable Argument Static Variable Global Variable Register Instance Variable Expression
64. Viewing Your Variables Variable Name The name of the variable as it appears in your code
65. Viewing Your Variables Dynamic Type Runtime type of the variable
66. Viewing Your Variables Variable Value Current value of the variable
67. Viewing Your Variables Variable Summary Summary for the variable, if there is one
68. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; }
69. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; }
70. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; } return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]];
71. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; } return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]];
72. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; } [_textField setStringValue:[self currentProcessNameString]];
73. Return Value When Stepping Out - (void)updateLabel { [_textField setStringValue:[self currentProcessNameString]]; } - (NSString *)currentProcessNameString { return [NSString stringWithFormat:@"Current process is %@", [[NSProcessInfo processInfo] processName]]; } [_textField setStringValue:[self currentProcessNameString]];
74. A Bit About Variable Summaries title = (__NSCFString *) 0x1234 @”WWDC12”
75. A Bit About Variable Summaries title = (__NSCFString *) 0x1234 @”WWDC12” [title description] Previously implemented with expressions:
76. A Bit About Variable Summaries NSCFString *) 0x1234 @”WWDC12” [title description] with expressions:
77. A Bit About Variable Summaries
78. A Bit About Variable Summaries Can change the state of your program
79. A Bit About Variable Summaries Can change the state of your program May not always work
80. A Bit About Variable Summaries LLDB Block of memory representing __NSCFString
81. A Bit About Variable Summaries LLDB Block of memory representing __NSCFString Character Data LLDB looks inside the object and reads the memory of the specific data it wants
82. Creating Custom Summaries import lldb LLDB
83. Creating Custom Summaries import lldb LLDB
84. Creating Custom Summaries import lldb LLDB
85. Creating Custom Summaries import lldb def circle_summary(valueObject, dictionary): LLDB
86. Creating Custom Summaries import lldb def circle_summary(valueObject, dictionary): # grab the bounds of the SKTCircle. bounds = valueObject.GetChildMemberWithName('_bounds') size = bounds.GetChildMemberWithName('size') … return 'Major Radius = ' + majorRadiusAsString + ', Minor Radius = ' + minorRadiusAsString + ', Area = ' + areaAsString LLDB
87. Creating Custom Summaries import lldb def circle_summary(valueObject, dictionary): SBValue # grab the bounds of the SKTCircle. bounds = valueObject.GetChildMemberWithName('_bounds') size = bounds.GetChildMemberWithName('size') … return 'Major Radius = ' + majorRadiusAsString + ', Minor Radius = ' + minorRadiusAsString + ', Area = ' + areaAsString LLDB
88. Creating Custom Summaries import lldb def circle_summary(valueObject, dictionary): Don’t use this parameter # grab the bounds of the SKTCircle. bounds = valueObject.GetChildMemberWithName('_bounds') size = bounds.GetChildMemberWithName('size') … return 'Major Radius = ' + majorRadiusAsString + ', Minor Radius = ' + minorRadiusAsString + ', Area = ' + areaAsString LLDB
89. Creating Custom Summaries import lldb def circle_summary(valueObject, dictionary): # grab the bounds of the SKTCircle. bounds = valueObject.GetChildMemberWithName('_bounds') size = bounds.GetChildMemberWithName('size') … return 'Major Radius = ' + majorRadiusAsString + ', Minor Radius = ' + minorRadiusAsString + ', Area = ' + areaAsString LLDB
90. Demo Variables view and custom LLDB summaries Troy Koelling Xcode Debugger UI Engineer
91. Advanced Debugging
92. Debugging as Root
93. Debugging as Root Edit Scheme ⌘<
94. Debugging as Root
95. What Is an XPC Service Privileged Bits Your App Process App Logic Crashy Bits
96. What Is an XPC Service Crashy Bits Privileged Bits Your App Process App Logic XPC Services (separate processes)
97. Demo Advanced debugging Han Ming Ong Xcode Debugger UI Engineer
98. More Information Michael Jurewitz Developer Tools Evangelist jury@apple.com Documentation LLDB Custom Summaries http://lldb.llvm.org/varformats.html Documentation LLDB Scripting http://lldb.llvm.org/scripting.html Apple Developer Forums http://devforums.apple.com
99. Related Sessions Debugging with LLDB Presidio Friday 10:15AM Cocoa Interprocess Communication with XPC Russian Hill Thursday 4:30PM OpenGL ES Tools and Techniques Pacific Heights Wednesday 3:15PM Learning Instruments Presidio Wednesday 4:30PM
100. Labs Xcode Lab Developer Tools Lab B Ongoing LLDB Lab Developer Tools Lab C Friday 11:30AM