在检查内存时，gdb如何显示十六进制和ASCII码？ [英] How can gdb show both hex and ascii when examing memory?

问题描述

0x111111：40'（'40'（'）使用x / 100c时，输出显示ascii和decimal。 / code>

gdb如何同时显示ascii和hex？

0x111111：0x28'C'0x28'C'


这种格式更好：

0x111111：0x28 0x28 ...'CC ...'



  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'\\\

 set $ addr = $ addr + 8 
 end 
 end 
 
文件xac 
用法：xac地址计数
结束
  





  $ 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系统（cmd）; 
 10} 
（gdb）break 9 
断点1在0x400666：文件co2.c，第9行。
（gdb）run 
断点1，main（）在co2.c：9 
 9系统（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'
  




When using x/100c, the output shows the both ascii and decimal.

0x111111: 40 '(' 40 '('

How can gdb show the ascii and hex at the same time ?

like

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

This format is better:

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

解决方案

You can do this with a macro. Iterate through the characters, and call appropriate 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'

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