x86架构调用栈分析

以一个简单求阶乘的代码为例：

 1 #include <stdio.h>
 2
 3 unsigned int fact(unsigned int n)
 4 {
 5     if (n == 0)
 6         return 1;
 7     return n * fact(n - 1);
 8 }
 9
10 int main(void)
11 {
12     int c = 0;
13
14     c = fact(5);
15
16     return c;
17 }

 1 void mbacktrace(int fps[], int n)
 2 {
 3     int *reg_fp = 0, *reg_fp_next = 0;
 4     int cnt = 0, i;
 5
 6     __asm__ __volatile__(
 7         "mov %%ebp, %0\t\n"
 8         : "=m"(reg_fp)
 9     );
10
11     reg_fp_next = reg_fp;
12     for (i = 0; i < n && reg_fp_next != 0; i++)
13     {
14         reg_fp_next = (int *)((int)*reg_fp); // get ebp
15         fps[i] = (int)(*(reg_fp + 1)); // get eip, or ret_addr
16         reg_fp = reg_fp_next;
17         printf("stack_fp[%d] = 0x%08x.\n", i, stack_fp[i]);
18     }
19 }