XCode的调试工具

LLDB

常用命令

• 列出和某个命令相关的命令：apropos thread
• 列出所有break points: (lldb) br l
• 删掉break: br delete 1
• 开关break: br e 1,br di 1
• 设置break point: b MyViewController.m :30
• 继续:c
• 断点后但不执行n,
• 进入某个函数:s
• 结束:finish
• 执行表达式expr

#隐藏view
expr self.view.hidden = yes
#variable:
expr int $a = 100 定义一个a变量值为100

增加符号断点

• 给所有viewdidload打断点:br set -n viewDidLoad
• 根据condition打断点：br mod -c "totalValue > 1000" 3
• 进入命令行模式：

(lldb) br com add 2
Enter your debugger command(s).  Type 'DONE' to end.
> bt
> continue
> DONE

函数堆栈,线程相关

• bt = thread backtrace
• br all
• thread list
• frame info
• frame select <num>
• frame variable

(lldb) frame variable
(TBCityStoreMenuViewController *const) self = 0x09646820
(SEL) _cmd = "onCoverFlowLayoutClicked:"
(UIButton *) btn = 0x09665d40
(lldb) frame variable self
(TBCityStoreMenuViewController *const) self = 0x09646820

• frame variable -F self
• watchpoint list
• watchpoint delete 1

#监控变量_x是否发生变化
watchpoint set variable _x

(lldb) watchpoint set variable _type
Watchpoint created: Watchpoint 1: addr = 0x0955c8d0 size = 4 state = enabled type = w
    watchpoint spec = '_type'
    new value: kGrid

如果x发生变化：

Watchpoint 1 hit:
old value: kGrid
new value: kCover

添加Python script

• LLDB contains an embedded python interperter，The entire API is exposed through python scripting bindings:

(lldb) script print(sys.version)
2.7.5 (default, Aug 25 2013, 00:04:04) 
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)]

• The script command parses raw Python commands:

(lldb) script
Python Interactive Interpreter. To exit, type 'quit()', 'exit()' or Ctrl-D.
>>> a = 3
>>> print a
3

• Run python scripts from a breakpoint
  • LLDB creates a Python function to encapsulate the scripts
  • if yout want to access the script variables outside the breakpoint,you must declare thhem as global variables
• 通过打断点来调用python函数：

(lldb) breakpoint command add -s python 1(break point的id)
(lldb) breakpoint command add -s python
Enter your Python command(s). Type 'DONE' to end.
def function(frame,bp_loc,internal_dict):
    """frame: the SBFrame for the location at which you stopped
       bp_loc: an SBBreakpointLocation for the breakpoint location information
       internal_dict: an LLDB support object not to be used"""

	//填写python函数体：
	variables = frame.GetVariables(False,True,False,True)
	for i in range(0,variables.GetSize()):
		variable = variables.GetValueAtIndex(i)
		print variable
		DONE

• 将方法定义在python脚本中：

def breakpoint_func(frame,bp_loc,dict):

frame : current stack frame of the breakpoint
bp_loc : the current breakpoint location
dict : the python session dictionary

#函数返回false，则lldb继续执行
#函数返回true，则lldb暂停执行

• import exsting scripts to be used during your debugging session
  • 将python文件引入进来(lldb) command script import ~/my_script.py
  • 将breakpoint和python函数关联起来：(lldb) breakpoint command add -F my.breakpoint_func
  • command script import "/Users/moxinxt/Desktop/tbcity-ipad/iCoupon4Ipad/iCoupon4Ipad/breakpoint.py"
• 使用Facebook Chisel

Attach到某个进程

我们也可以使用LLDB来debug某个进程：process attach --name WWDCDemo --waitfor //等待WWDCDemo启动，并将lldb挂到WWDCDemo上

debug二进制

Clang

• clang -c test.c
  • -E Preprocess,but don’t compile
  • -S Compile, but don’t assemble
  • -c Asseble, but don’t link
• clang -o test test.c 编译test.c，生成test
• clang -o test test.m -framework foundation 带上link的framework

Lipo

• lipo -info 二进制包
• lipo xx.a -thin arm64

otool

otool用来查看Mach-O文件格式

• otool -h:查看头部信息
• otool -l:查看LOAD CMD
• otool -t:Dump binary information
• otool -t -V: Disassmble the binary

dSYM & DWARF

XCode自带了导出二进制符号表的工具:dsymutil

• 提取.dSYM:dsymutil xx.app/xx -o xx.dSYM
• 查看dSYM中的UUID: dwarfdump --uuid VZMachOTools.dSYM/Contents/Resources/DWARF
• 查看dSYM中的info信息: dwarfdump -e --debug-info VZMachOTools.dSYM/Contents/Resources/DWARF > info.txt
• 查看dSYM中的line信息: dwarfdump -e --debug-line VZMachOTools.dSYM/Contents/Resources/DWARF > line.txt

Security & CodeSign

Security用来执行与证书签名相关的命令：

• 显示出所有可以用于签名的证书：$ security find-identity -v -p codesigning

lldb

optool

• 官方文档
• 作用：
  • appstore 二进制 去壳：./optool [-w] -t 二进制
  • 向二进制中注入dylib