信号 调试 段错误 X86

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#define __USE_GNU
#include <ucontext.h>

static void sigsegv_handler(int signum, struct siginfo * info, void * ptr)
{
    static const char *si_codes[3] = {"", "SEGV_MAPERR", "SEGV_ACCERR"};
    int i;
    struct ucontext *ucontext = (struct ucontext *)ptr;

    printf("Segmentation Fault Trace:\n");
    printf("info.si_signo     %d\n",      signum);
    printf("info.si_errno     %d\n",      info->si_errno);
    printf("info.si_code      %d (%s)\n", info->si_code, si_codes[info->si_code]);
    printf("info.si_addr      %p\n",      info->si_addr);
    /*for x86*/
    printf("the eip           0x%x\n",    ucontext->uc_mcontext.gregs[REG_EIP]);
    exit (-1);
}

static void catch_sigsegv ()
{
    struct sigaction action;
    memset (&action, 0, sizeof(action));
    action.sa_sigaction = sigsegv_handler;
    action.sa_flags     = SA_SIGINFO;
    if (sigaction(SIGSEGV, &action, NULL) < 0)
    {
        perror("sigaction");
    }
    return;
}

void dummy_function (void)
{
    unsigned char *ptr = 0x00;
    *ptr = 0x00;
}

int main (void)
{
    catch_sigsegv();
    dummy_function ();
    return 0;
}

       #include <execinfo.h>
       #include <stdio.h>
       #include <stdlib.h>
       #include <unistd.h>

       void
       myfunc3(void)
       {
           int j, nptrs;
       #define SIZE 100
           void *buffer[100];
           char **strings;

           nptrs = backtrace(buffer, SIZE);
           printf("backtrace() returned %d addresses\n", nptrs);

           /* The call backtrace_symbols_fd(buffer, nptrs, STDOUT_FILENO)
              would produce similar output to the following: */

           strings = backtrace_symbols(buffer, nptrs);
           if (strings == NULL) {
               perror("backtrace_symbols");
               exit(EXIT_FAILURE);
           }

           for (j = 0; j < nptrs; j++)
               printf("%s\n", strings[j]);

           free(strings);
       }

       static void   /* "static" means don't export the symbol... */
       myfunc2(void)
       {
           myfunc3();
       }

       void
       myfunc(int ncalls)
       {
           if (ncalls > 1)
               myfunc(ncalls - 1);
           else
               myfunc2();
       }

       int
       main(int argc, char *argv[])
       {
           if (argc != 2) {
               fprintf(stderr, "%s num-calls\n", argv[0]);
               exit(EXIT_FAILURE);
           }

           myfunc(atoi(argv[1]));
           exit(EXIT_SUCCESS);
       }