【跟我一起学gdb】(9)自动化gdb脚本之 给指定断点 挂载将每次bt堆栈信息都保存到日志文件的命令

main.c

tom@ubuntu:~/dvp$ cat -n main.c
     1	typedef struct
     2	{
     3		int iW;
     4		int iH;
     5		int iX;
     6		int iY;
     7	}BOX_ST;
     8	
     9	BOX_ST stBox;
    10	static int s = 0;
    11	
    12	int sum(const int a, const int b)
    13	{
    14		int c = a + b;
    15		
    16		return c;
    17	}
    18	
    19	int main()
    20	{
    21		for (int i = 0; i < 18; ++i)
    22		{
    23			stBox.iW = i;
    24			stBox.iH = i;
    25			stBox.iX = i;
    26			stBox.iY = i;
    27			
    28			s = sum(i,i+2);
    29		}
    30		
    31		return 0;
    32	}
tom@ubuntu:~/dvp$ 

gdb自动化脚本

功能：断点处的每次堆栈都写到本地日志文件

示例：

sum函数的入参a模5等于0时给sum处设置断点

每次运行到sum断点处时，都把堆栈信息写到本地日志文件gdb.log中。

tom@ubuntu:~/dvp$ cat ./gdbcmd_break-btlog.txt 
set pagination off
set logging file gdb.log
set logging overwrite
set logging on

break sum if 0 == (a % 5)
commands
	silent
	printf "\n"
	bt
	continue
end
tom@ubuntu:~/dvp$ 

gdb自动化脚本使用

tom@ubuntu:~/dvp$ gdb ./a.out -x ./gdbcmd_break-btlog.txt
Reading symbols from ./a.out...done.
Breakpoint 1 at 0x4004e0: file main.c, line 14.
(gdb) info b
Num     Type           Disp Enb Address            What
1       breakpoint     keep y   0x00000000004004e0 in sum at main.c:14
	stop only if 0 == (a % 5)
        silent
        printf "\n"
        bt
        continue
(gdb) run
Starting program: /home/tom/dvp/a.out 

#0  sum (a=0, b=2) at main.c:14
#1  0x0000000000400537 in main () at main.c:28

#0  sum (a=5, b=7) at main.c:14
#1  0x0000000000400537 in main () at main.c:28

#0  sum (a=10, b=12) at main.c:14
#1  0x0000000000400537 in main () at main.c:28

#0  sum (a=15, b=17) at main.c:14
#1  0x0000000000400537 in main () at main.c:28
[Inferior 1 (process 54637) exited normally]
(gdb) 

查看本地堆栈日志文件

(gdb) quit
tom@ubuntu:~/dvp$ cat -n ./gdb.log 
     1	Breakpoint 1 at 0x4004e0: file main.c, line 14.
     2	Num     Type           Disp Enb Address            What
     3	1       breakpoint     keep y   0x00000000004004e0 in sum at main.c:14
     4		stop only if 0 == (a % 5)
     5	        silent
     6	        printf "\n"
     7	        bt
     8	        continue
     9	Starting program: /home/tom/dvp/a.out 
    10	
    11	#0  sum (a=0, b=2) at main.c:14
    12	#1  0x0000000000400537 in main () at main.c:28
    13	
    14	#0  sum (a=5, b=7) at main.c:14
    15	#1  0x0000000000400537 in main () at main.c:28
    16	
    17	#0  sum (a=10, b=12) at main.c:14
    18	#1  0x0000000000400537 in main () at main.c:28
    19	
    20	#0  sum (a=15, b=17) at main.c:14
    21	#1  0x0000000000400537 in main () at main.c:28
    22	[Inferior 1 (process 54637) exited normally]
tom@ubuntu:~/dvp$ 

《完》