replace usleep() for systems that don't have them

This function is marked obsolete in POSIX.1-2001 and removed in
POSIX.1-2008.

Conditionally replaced with nanosleep().

Signed-off-by: Daniel Mierswa <impulze@impulze.org>

configure.ac

@@ -140,6 +140,7 @@ AC_CHECK_FUNCS(
 	fsync \
 	getdomainname \
 	get_current_dir_name \
+	usleep \
 	nanosleep \
 	personality \
 	updwtmp \

hwclock/kd.c

@@ -17,6 +17,7 @@ probe_for_kd_clock() {
 #include <sys/ioctl.h>
 
 #include "nls.h"
+#include "usleep.h"
 
 static int con_fd = -1;		/* opened by probe_for_kd_clock() */
 				/* never closed */

include/Makefile.am

@@ -16,6 +16,7 @@ dist_noinst_HEADERS = \
 	pttype.h \
 	setproctitle.h \
 	swapheader.h \
+	usleep.h \
 	wholedisk.h \
 	widechar.h \
 	xstrncpy.h

include/usleep.h

@@ -0,0 +1,18 @@
+#ifndef UTIL_LINUX_USLEEP_H
+#define UTIL_LINUX_USLEEP_H
+
+#ifndef HAVE_USLEEP
+/*
+ * This function is marked obsolete in POSIX.1-2001 and removed in
+ * POSIX.1-2008. It is replaced with nanosleep().
+ */
+# define usleep(x) \
+	do { \
+		struct timespec xsleep; \
+		xsleep.tv_sec = x / 1000 / 1000; \
+		xsleep.tv_nsec = (x - xsleep.tv_sec * 1000 * 1000) * 1000; \
+		nanosleep(&xsleep, NULL); \
+	} while (0)
+#endif
+
+#endif /* UTIL_LINUX_USLEEP_H */

login-utils/shutdown.c

@@ -76,6 +76,7 @@
 #include "pathnames.h"
 #include "xstrncpy.h"
 #include "nls.h"
+#include "usleep.h"
 
 static void usage(void), int_handler(int), write_user(struct utmp *);
 static void wall(void), write_wtmp(void), unmount_disks(void);

mount/fstab.c

@@ -19,6 +19,7 @@
 #include "fsprobe.h"
 #include "pathnames.h"
 #include "nls.h"
+#include "usleep.h"
 
 #define streq(s, t)	(strcmp ((s), (t)) == 0)
 

sys-utils/rtcwake.c

@@ -36,6 +36,7 @@
 #include <linux/rtc.h>
 
 #include "nls.h"
+#include "usleep.h"
 
 /* constants from legacy PC/AT hardware */
 #define	RTC_PF	0x40

text-utils/tailf.c

@@ -41,6 +41,7 @@
 #include <sys/inotify.h>
 #endif
 #include "nls.h"
+#include "usleep.h"
 
 #define DEFAULT_LINES  10