libfreeinit.c

#include <sys/socket.h>
#include <sys/un.h>

#include <errno.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include "libfreeinit.h"

int
freeinit_notify(const char *info)
{
	ssize_t r;
	int fd;
	const char *path;

	if (info == NULL)
		return -EINVAL;

	path = getenv("NOTIFY_SOCKET");
	if (path == NULL)
		return 0;

	fd = socket(AF_UNIX, SOCK_DGRAM, 0);
	if (fd < 0)
		return -errno;

	struct sockaddr_un addr;
	memset(&addr, 0, sizeof(struct sockaddr_un));
	addr.sun_family = AF_UNIX;
	strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);

	r = sendto(fd, info, strlen(info), 0, (struct sockaddr *)&addr,
	    sizeof(struct sockaddr_un));
	if (r < 0) {
		r = errno;
		close(fd);
		return -r;
	}

	close(fd);

	return r;
}

int
freeinit_notifyf(const char *fmt, ...)
{
	char *info;
	va_list args;
	ssize_t r;

	if (fmt == NULL)
		return -EINVAL;

	va_start(args, fmt);
	r = vasprintf(&info, fmt, args);
	va_end(args);
	if (r < 0)
		return -ENOMEM;

	r = freeinit_notify(info);
	free(info);

	return r;
}

void
freeinit_clearenv_notify()
{
	unsetenv("NOTIFY_SOCKET");
}

void
freeinit_clearenv_fdpassing()
{
	unsetenv("LISTEN_FDS");
	unsetenv("LISTEN_FDNAMES");
	unsetenv("LISTEN_PID");
}