Fix header comment to match module title.

[gnulib.git] / lib / nanosleep.c

diff --git a/lib/nanosleep.c b/lib/nanosleep.c
index 126a026..2f91c31 100644 (file)
--- a/lib/nanosleep.c
+++ b/lib/nanosleep.c
@@ -1,5 +1,5 @@
 /* Provide a replacement for the POSIX nanosleep function.
-   Copyright (C) 1999 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2000, 2002, 2004 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
@@ -18,79 +18,88 @@
 /* written by Jim Meyering */
 
 #include <config.h>
+
+/* Undefine nanosleep here so any prototype is not redefined to be a
+   prototype for rpl_nanosleep. (they'd conflict e.g., on alpha-dec-osf3.2)  */
+#undef nanosleep
+
+#include <stdbool.h>
 #include <stdio.h>
 #include <sys/types.h>
 #include <signal.h>
 
 #include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
 
 #if HAVE_UNISTD_H
 # include <unistd.h>
 #endif
 
-#include <time.h>
-/* FIXME: is including both like this kosher?  */
-#include <sys/time.h>
+/* 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
+
+#include "timespec.h"
 
-static int suspended;
+static sig_atomic_t volatile suspended;
 
 /* Handle SIGCONT. */
 
 static void
 sighandler (int sig)
 {
-#ifdef SA_INTERRUPT
-  struct sigaction sigact;
-
-  sigact.sa_handler = SIG_DFL;
-  sigemptyset (&sigact.sa_mask);
-  sigact.sa_flags = 0;
-  sigaction (sig, &sigact, NULL);
-#else
-  signal (sig, SIG_DFL);
-#endif
-
   suspended = 1;
-  kill (getpid (), sig);
 }
 
-/* Sleep for USEC microseconds. */
+/* FIXME: comment */
 
 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 = 1000 * ts_delay->tv_nsec;
+  tv_delay.tv_usec = (ts_delay->tv_nsec + 999) / 1000;
+  if (tv_delay.tv_usec == 1000000)
+    {
+      tv_delay.tv_sec++;
+      tv_delay.tv_usec = 0;
+    }
   select (0, (void *) 0, (void *) 0, (void *) 0, &tv_delay);
 }
 
+/* FIXME: comment */
+
 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
+  static bool initialized;
+
+#ifdef SA_NOCLDSTOP
   struct sigaction oldact, newact;
 #endif
 
   suspended = 0;
 
-  /* set up sig handler -- but maybe only do this the first time?  */
-#ifdef SA_INTERRUPT
-  newact.sa_handler = sighandler;
-  sigemptyset (&newact.sa_mask);
-  newact.sa_flags = 0;
-
-  sigaction (SIGCONT, NULL, &oldact);
-  if (oldact.sa_handler != SIG_IGN)
-    sigaction (SIGCONT, &newact, NULL);
+  /* set up sig handler */
+  if (! initialized)
+    {
+#ifdef SA_NOCLDSTOP
+      newact.sa_handler = sighandler;
+      sigemptyset (&newact.sa_mask);
+      newact.sa_flags = 0;
+
+      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);
+      if (signal (SIGCONT, SIG_IGN) != SIG_IGN)
+       signal (SIGCONT, sighandler);
 #endif
+      initialized = true;
+    }
 
   my_usleep (requested_delay);
 
@@ -99,11 +108,11 @@ nanosleep (const struct timespec *requested_delay,
       /* Calculate time remaining.  */
       /* FIXME: the code in sleep doesn't use this, so there's no
         rush to implement it.  */
+
+      errno = EINTR;
     }
 
   /* FIXME: Restore sig handler?  */
 
-  errno = EINTR;
-
   return suspended;
 }