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/* This testcase is part of GDB, the GNU debugger.
Copyright 2004-2021 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <sys/time.h>
#include <errno.h>
static volatile int done;
static volatile int dummy;
static volatile int no_handler;
static void
handler (int sig)
{
/* This is more than one write so that the breakpoint location below
is more than one instruction away. */
done = 1;
done = 1;
done = 1;
done = 1; /* other handler location */
} /* handler */
struct itimerval itime;
struct sigaction action;
/* The enum is so that GDB can easily see these macro values. */
enum {
itimer_real = ITIMER_REAL,
itimer_virtual = ITIMER_VIRTUAL
} itimer = ITIMER_VIRTUAL;
int
main ()
{
int res;
/* Set up the signal handler. */
memset (&action, 0, sizeof (action));
action.sa_handler = no_handler ? SIG_IGN : handler;
sigaction (SIGVTALRM, &action, NULL);
sigaction (SIGALRM, &action, NULL);
/* The values needed for the itimer. This needs to be at least long
enough for the setitimer() call to return. */
memset (&itime, 0, sizeof (itime));
itime.it_value.tv_usec = 250 * 1000;
/* Loop for ever, constantly taking an interrupt. */
while (1)
{
/* Set up a one-off timer. A timer, rather than SIGSEGV, is
used as after a timer handler finishes the interrupted code
can safely resume. */
res = setitimer (itimer, &itime, NULL);
if (res == -1)
{
printf ("First call to setitimer failed, errno = %d\r\n",errno);
itimer = ITIMER_REAL;
res = setitimer (itimer, &itime, NULL);
if (res == -1)
{
printf ("Second call to setitimer failed, errno = %d\r\n",errno);
return 1;
}
}
/* Wait. Issue a couple writes to a dummy volatile var to be
reasonably sure our simple "get-next-pc" logic doesn't
stumble on branches. */
dummy = 0; dummy = 0; while (!done);
done = 0;
}
return 0;
}
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