Custom breakpoint

gistfile1.txt

import gdb
open_files = {}
class PrintArgsBreakpoint(gdb.Breakpoint):

    def __init__(self, fn_name, filename):
        super(PrintArgsBreakpoint, self).__init__(fn_name)
        self.filename = filename
        self.fn_name = fn_name
        self.file_opened = False

    def stop(self):
        global open_files
        file = open_files.get(self.filename)
        if file is None:
            file = open(self.filename, 'a')
            open_files[self.filename] = file
            self.file_opened = True

        s = gdb.execute("info args", to_string=True)
        res = "arguments for '{}'\n--------------\n{}--------------\n\n".format(self.fn_name, s)
        file.write(res)
        file.flush()
        # we return false to not stop; making GDB just carry on merrily (as if it was executing "continue"
        return False


class FnBreakpointPrintArgs(gdb.Command):

    def __init__(self):
        super(FnBreakpointPrintArgs, self).__init__("bpargs", gdb.COMMAND_USER)
        self.name = "bpargs"

    def invoke(self, args, from_tty):
        [expr, filename] = gdb.string_to_argv(args)
        print("logging args of function {} > {}".format(expr, filename))
        bp = PrintArgsBreakpoint(expr, filename)


cmd = FnBreakpointPrintArgs()