/*
 * No copyright is claimed.  This code is in the public domain; do with
 * it what you wish.
 *
 * Written by Karel Zak <kzak@redhat.com>
 *            Petr Uzel <petr.uzel@suse.cz>
 */

#include <unistd.h>
#include <time.h>
#include <errno.h>

/*
 * The usleep function was marked obsolete in POSIX.1-2001 and was removed
 * in POSIX.1-2008.  It was replaced with nanosleep() that provides more
 * advantages (like no interaction with signals and other timer functions).
 */
static inline int xusleep(useconds_t usec)
{
	struct timespec waittime = {
		.tv_sec   =  usec / 1000000L,
		.tv_nsec  = (usec % 1000000L) * 1000
	};
	return nanosleep(&waittime, NULL);
}

int write_all(int fd, const void *buf, size_t count)
{
	while (count) {
		ssize_t tmp;

		errno = 0;
		tmp = write(fd, buf, count);
		if (tmp > 0) {
			count -= tmp;
			if (count)
				buf = (const void *) ((const char *) buf + tmp);
		} else if (errno != EINTR && errno != EAGAIN)
			return -1;
		if (errno == EAGAIN)	/* Try later, *sigh* */
			xusleep(250000);
	}
	return 0;
}