gdb在检查内存时如何同时显示hex和ascii？

使用 x/100c 时，输出显示 ascii 和十进制。

0x111111: 40 '(' 40 '('

gdb如何同时显示ascii和hex？

like

0x111111: 0x28 'C' 0x28 'C'

这种格式更好：

0x111111: 0x28 0x28 ... 'CC...'

您可以使用宏来完成此操作。遍历字符，并调用适当的 printfs。

define xac
    dont-repeat
    set $addr = (char *)($arg0)
    set $endaddr = $addr + $arg1
    while $addr < $endaddr
        printf "%p: ", $addr
        set $lineendaddr = $addr + 8
        if $lineendaddr > $endaddr
            set $lineendaddr = $endaddr
        end
        set $a = $addr
        while $a < $lineendaddr
            printf "0x%02x ", *(unsigned char *)$a
            set $a++
        end
        printf "'"
        set $a = $addr
        while $a < $lineendaddr
            printf "%c", *(char *)$a
            set $a++
        end
        printf "'\n"
        set $addr = $addr + 8
    end
end

document xac
usage: xac address count
end

$ gdb co2
(gdb) list
1       #include <stdlib.h>
2       #include <stdio.h>
3
4       main()
5       {
6               char cmd[50];
7
8               sprintf(cmd, "cat /proc/%d/maps", getpid());
9               system(cmd);
10      }
(gdb) break 9
Breakpoint 1 at 0x400666: file co2.c, line 9.
(gdb) run
Breakpoint 1, main () at co2.c:9
9               system(cmd);
(gdb) xac cmd 20
0x7fffffffe110: 0x63 0x61 0x74 0x20 0x2f 0x70 0x72 0x6f 'cat /pro'
0x7fffffffe118: 0x63 0x2f 0x32 0x30 0x37 0x37 0x38 0x2f 'c/20778/'
0x7fffffffe120: 0x6d 0x61 0x70 0x73 'maps'