/* Provide a replacement for the POSIX nanosleep function.
- Copyright (C) 1999, 2000 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ Copyright (C) 1999, 2000, 2002, 2004, 2005, 2006, 2007, 2008 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 2, or (at your option)
- any later version.
+ 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
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, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* written by Jim Meyering */
#include <config.h>
+
+#include <time.h>
+
+#include "sig-handler.h"
+#include "timespec.h"
+
+#include <stdbool.h>
#include <stdio.h>
#include <sys/types.h>
+#include <sys/select.h>
#include <signal.h>
+#include <sys/time.h>
#include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
+#include <unistd.h>
+
+#undef nanosleep
+
+enum { BILLION = 1000 * 1000 * 1000 };
+
+#if HAVE_BUG_BIG_NANOSLEEP
+
+void
+getnow (struct timespec *t)
+{
+# if defined CLOCK_MONOTONIC && HAVE_CLOCK_GETTIME
+ if (clock_gettime (CLOCK_MONOTONIC, t) == 0)
+ return;
+# endif
+ gettime (t);
+}
+
+int
+rpl_nanosleep (const struct timespec *requested_delay,
+ struct timespec *remaining_delay)
+{
+ /* nanosleep mishandles large sleeps due to internal overflow
+ problems, so check that the proper amount of time has actually
+ elapsed. */
+
+ struct timespec delay = *requested_delay;
+ struct timespec t0;
+ getnow (&t0);
-#include "nanosleep.h"
+ for (;;)
+ {
+ int r = nanosleep (&delay, remaining_delay);
+ if (r == 0)
+ {
+ time_t secs_sofar;
+ struct timespec now;
+ getnow (&now);
+
+ secs_sofar = now.tv_sec - t0.tv_sec;
+ if (requested_delay->tv_sec < secs_sofar)
+ return 0;
+ delay.tv_sec = requested_delay->tv_sec - secs_sofar;
+ delay.tv_nsec = requested_delay->tv_nsec - (now.tv_nsec - t0.tv_nsec);
+ if (delay.tv_nsec < 0)
+ {
+ if (delay.tv_sec == 0)
+ return 0;
+ delay.tv_nsec += BILLION;
+ delay.tv_sec--;
+ }
+ else if (BILLION <= delay.tv_nsec)
+ {
+ delay.tv_nsec -= BILLION;
+ delay.tv_sec++;
+ }
+ }
+ }
+}
+
+#else
+
+/* Some systems (MSDOS) don't have SIGCONT.
+ Using SIGTERM here turns the signal-handling code below
+ into a no-op on such systems. */
+# ifndef SIGCONT
+# define SIGCONT SIGTERM
+# endif
-static int suspended;
-int first_call = 1;
+static sig_atomic_t volatile suspended;
/* Handle SIGCONT. */
suspended = 1;
}
-/* FIXME: comment */
+/* Suspend execution for at least *TS_DELAY seconds. */
static void
my_usleep (const struct timespec *ts_delay)
{
struct timeval tv_delay;
tv_delay.tv_sec = ts_delay->tv_sec;
- tv_delay.tv_usec = ts_delay->tv_nsec / 1000;
- select (0, (void *) 0, (void *) 0, (void *) 0, &tv_delay);
+ tv_delay.tv_usec = (ts_delay->tv_nsec + 999) / 1000;
+ if (tv_delay.tv_usec == 1000000)
+ {
+ time_t t1 = tv_delay.tv_sec + 1;
+ if (t1 < tv_delay.tv_sec)
+ tv_delay.tv_usec = 1000000 - 1; /* close enough */
+ else
+ {
+ tv_delay.tv_sec = t1;
+ tv_delay.tv_usec = 0;
+ }
+ }
+ select (0, NULL, NULL, NULL, &tv_delay);
}
-/* FIXME: comment */
+/* Suspend execution for at least *REQUESTED_DELAY seconds. The
+ *REMAINING_DELAY part isn't implemented yet. */
int
-nanosleep (const struct timespec *requested_delay,
- struct timespec *remaining_delay)
+rpl_nanosleep (const struct timespec *requested_delay,
+ struct timespec *remaining_delay)
{
-#ifdef SA_INTERRUPT
- struct sigaction oldact, newact;
-#endif
-
- suspended = 0;
+ static bool initialized;
/* set up sig handler */
- if (first_call)
+ if (! initialized)
{
-#ifdef SA_INTERRUPT
- newact.sa_handler = sighandler;
- sigemptyset (&newact.sa_mask);
- newact.sa_flags = 0;
+ struct sigaction oldact;
sigaction (SIGCONT, NULL, &oldact);
- if (oldact.sa_handler != SIG_IGN)
- sigaction (SIGCONT, &newact, NULL);
-#else
- if (signal (SIGCONT, SIG_IGN) != SIG_IGN)
- signal (SIGCONT, sighandler);
-#endif
- first_call = 0;
+ if (get_handler (&oldact) != SIG_IGN)
+ {
+ struct sigaction newact;
+
+ newact.sa_handler = sighandler;
+ sigemptyset (&newact.sa_mask);
+ newact.sa_flags = 0;
+ sigaction (SIGCONT, &newact, NULL);
+ }
+ initialized = true;
}
+ suspended = 0;
+
my_usleep (requested_delay);
if (suspended)
return suspended;
}
+#endif
projects / gnulib.git / blobdiff