debugger_linux

Using debugger

• For using debugger, you simply need to run the compiled debugger by passing the compiled test file as the first parameter which needs to be debugged.
• For eg. if you need to debug the test.cpp file then just pass its compiled file (like test) as shown in the command below.

 ./debugger ./test

Note: As dwarf library is used in the codebase, you need to compile the test.cpp file with following command - gcc -g test.cpp -o test.

• If you need to compile the debugger after making updates to the source code (launch_exec.cpp), use the following command

g++ -gdwarf-2 launch_exec.cpp -o debugger $(pkg-config --cflags --libs libdwarf++)

Features

Command	Feature provided
continue	Continue execution of the program
break 0xaddress	Add breakpoint at particular address
break < filename >:< line >	Add breakpoint at particular line of file
break func_name	Add breakpoint at function
register dump	Dump registers
register read reg_name	Read register values by providing register name
register write reg_name value	Write specified value in the register
memory read addr	Prints the value at the particular address
memory write addr value	Writes the specified value at particular address
stepinst	Steps the current instruction even if there is a breakpoint
step	Steps in - step over instruction till we reach the new line
next	Steps over - sets a breakpoint at every line in the current function
finish	Steps out - sets breakpoint at return address and continue execution from there
symbol sym_name	Lookups the particular symbol
backtrace	Prints all the frames till the main function using stack unwinding
variables	Reads the variables present till the current address

References

This debugger is made following the blogpost - Writing a Linux Debugger (https://blog.tartanllama.xyz/writing-a-linux-debugger-setup/).