.gdbinit.py

import hexdump
import gdb

class HexdumpCmd(gdb.Command):
    """Hexdump memory: hd [addr [size]]
    Exaples:
        hd 0x409130 0x20
        hd &main_arena
        hd $5
    """
    def __init__(self):
        super(HexdumpCmd, self).__init__("hd", gdb.COMMAND_DATA, gdb.COMPLETE_SYMBOL)
        self._ptr = None
        self._size = 256

    def invoke(self, argument, from_tty):
        args = list(map(gdb.parse_and_eval, gdb.string_to_argv(argument)))
        args = list(map(int, args))
        if not args:
            args.append(self._ptr)

        if len(args) < 2:
            args.append(256)

        self._ptr = args[0]
        self._size = args[1]
        hexdump.hexdump(gdb.selected_inferior().read_memory(self._ptr, self._size))

        self._ptr += self._size

HexdumpCmd()