C++程序  |  75行  |  1.79 KB

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

static void breakme(int line)
{
   fprintf(stderr, "breakme function called from line %d\n", line);
   fflush(stderr);
}
static char undefined[10] = "undefined";
int main (int argc, char *argv[])
{

   /* we will test 
      read watchpoint at 0,
      read/write watchpoints at 4
      write watchpoints at 8 */

   breakme(__LINE__); //break1

   /* We verify read watchpoints are triggered at 0 and 4, not at 8 */
   fprintf(stderr, "before reading 0/4/8\n");
   if (undefined[0] == 'u')
      fprintf(stderr, "u: Expected value at 0\n");
   else
      fprintf(stderr, "u: Unexpected value at 0\n");
   
   if (undefined[4] == 'f')
      fprintf(stderr, "f: Expected value at 4\n");
   else
      fprintf(stderr, "f: Unexpected value at 4\n");
   
   if (undefined[8] == 'd')
      fprintf(stderr, "d: Expected value at 8\n");
   else
      fprintf(stderr, "d: Unexpected value at 8\n");


   /* We verify write watchpoints are triggered at 4 and 8, not at 0 */
   fprintf(stderr, "before writing 0\n");
   undefined[0] = 'U';

   fprintf(stderr, "before writing 4\n");
   undefined[4] = 'F';

   fprintf(stderr, "before writing 8\n");
   undefined[8] = 'D';

   fprintf(stderr, "after writing 8\n");

   /* after having remove the watchpoints, check we can read and write
      without break. */
   fprintf(stderr, "value %s\n", undefined);

   fprintf(stderr, "before rewriting 0\n");
   undefined[0] = '0';

   fprintf(stderr, "before rewriting 4\n");
   undefined[4] = '4';

   fprintf(stderr, "before rewriting 8\n");
   undefined[8] = '8';
   
   fprintf(stderr, "value %s\n", undefined);

   {
      char *k50 = malloc(50000);
      memset (k50, 'p', 50000);
      fprintf(stderr, "value of k50[1000] %c\n", k50[1000]);
      free(k50); //break2
   }

   exit(0);
}