inetd.c

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· C语言 代码 · 共 646 行 · 第 1/2 页

void
reapchild()
{
	union wait status;
	int pid;
	register struct servtab *sep;

	for (;;) {
		pid = wait3(&status, WNOHANG, 0);
		if (pid <= 0)
			break;
		if (debug)
			fprintf(stderr, "%d reaped\n", pid);
		for (sep = servtab; sep; sep = sep->se_next)
			if (sep->se_wait == pid) {
				if (status.w_status)
					syslog(LOG_WARNING,
					    "%s: exit status 0x%x",
					    sep->se_server, status);
				if (debug)
					fprintf(stderr, "restored %s, fd %d\n",
					    sep->se_service, sep->se_fd);
				pickbit(allsock, sep->se_fd);
				sep->se_wait = 1;
			}
	}
}

void
config()
{
	register struct servtab *sep, *cp, **sepp;
	struct servtab *getconfigent(), *enter();
	int omask;
	int on = 1;

	if (!setconfig()) {
		syslog(LOG_ERR, "%s: %m", conffile);
		return;
	}
	for (sep = servtab; sep; sep = sep->se_next)
		sep->se_checked = 0;
	while (cp = getconfigent()) {
		for (sep = servtab; sep; sep = sep->se_next)
			if (strcmp(sep->se_service, cp->se_service) == 0 &&
			    strcmp(sep->se_proto, cp->se_proto) == 0)
				break;
		if (sep != 0) {
			int i;

			omask = sigblock(mask(SIGCHLD));
			sep->se_wait = cp->se_wait;
#define SWAP(a, b) { char *c = a; a = b; b = c; }
			if (cp->se_server)
				SWAP(sep->se_server, cp->se_server);
			for (i = 0; i < MAXARGV; i++)
				SWAP(sep->se_argv[i], cp->se_argv[i]);
			(void) sigsetmask(omask);
			freeconfig(cp);
		} else
			sep = enter(cp);
		sep->se_checked = 1;
		if (sep->se_fd != -1)
			continue;
		sp = getservbyname(sep->se_service, sep->se_proto);
		if (sp == 0) {
			syslog(LOG_ERR, "%s/%s: unknown service",
			    sep->se_service, sep->se_proto);
			continue;
		}
		sep->se_ctrladdr.sin_port = sp->s_port;
		if ((sep->se_fd = socket(AF_INET, sep->se_socktype, 0)) < 0) {
			syslog(LOG_ERR, "%s/%s: socket: %m",
			    sep->se_service, sep->se_proto);
			continue;
		}
#define turnon(fd, opt) \
setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof(on))
		if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
		    turnon(sep->se_fd, SO_DEBUG) < 0)
			syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
		if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
			syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %s %m",sep->se_service);
#undef turnon
		if (bind(sep->se_fd, &sep->se_ctrladdr,
		    sizeof (sep->se_ctrladdr), 0) < 0) {
			syslog(LOG_ERR, "%s/%s: bind: %m",
			    sep->se_service, sep->se_proto);
			continue;
		}
		if (sep->se_socktype == SOCK_STREAM)
			(void) listen(sep->se_fd, 10);
		pickbit(allsock, sep->se_fd);
	}
	endconfig();
	/*
	 * Purge anything not looked at above.
	 */
	omask = sigblock(mask(SIGCHLD));
	sepp = &servtab;
	while (sep = *sepp) {
		if (sep->se_checked) {
			sepp = &sep->se_next;
			continue;
		}
		*sepp = sep->se_next;
		if (sep->se_fd != -1) {
			clearbit(allsock, sep->se_fd);
			clearbit(delaysock, sep->se_fd);
			if (anybit(delaysock, FDWORDS) == 0) {
				seltimer = NULL;
			}
			(void) close(sep->se_fd);
		}
		freeconfig(sep);
		free((char *)sep);
	}
	(void) sigsetmask(omask);
}

struct servtab *
enter(cp)
	struct servtab *cp;
{
	register struct servtab *sep;
	int omask;
	char *strdup();

	sep = (struct servtab *)malloc(sizeof (*sep));
	if (sep == (struct servtab *)0) {
		syslog(LOG_ERR, "Out of memory.");
		exit(-1);
	}
	*sep = *cp;
	sep->se_fd = -1;
	omask = sigblock(mask(SIGCHLD));
	sep->se_next = servtab;
	servtab = sep;
	(void) sigsetmask(omask);
	return (sep);
}

FILE	*fconfig = NULL;
struct	servtab serv;
char	line[256];
char	*skip(), *nextline();

setconfig()
{

	if (fconfig != NULL) {
		(void) fseek(fconfig, 0, L_SET);
		return (1);
	}
	fconfig = fopen(conffile, "r");
	return (fconfig != NULL);
}

endconfig()
{

	if (fconfig == NULL)
		return;
	(void) fclose(fconfig);
	fconfig = NULL;
}

struct servtab *
getconfigent()
{
	register struct servtab *sep = &serv;
	char *cp, *arg;
	int argc;

	while ((cp = nextline(fconfig)) && ((*cp == '#') || (strlen(cp) == 0)))
		;
	if (cp == NULL)
		return ((struct servtab *)0);
	sep->se_service = strdup(skip(&cp));
	arg = skip(&cp);
	if (strcmp(arg, "stream") == 0)
		sep->se_socktype = SOCK_STREAM;
	else if (strcmp(arg, "dgram") == 0)
		sep->se_socktype = SOCK_DGRAM;
	else if (strcmp(arg, "rdm") == 0)
		sep->se_socktype = SOCK_RDM;
	else if (strcmp(arg, "seqpacket") == 0)
		sep->se_socktype = SOCK_SEQPACKET;
	else if (strcmp(arg, "raw") == 0)
		sep->se_socktype = SOCK_RAW;
	else
		sep->se_socktype = -1;
	sep->se_proto = strdup(skip(&cp));
	arg = skip(&cp);
	sep->se_wait = strcmp(arg, "wait") == 0;
	/*
	 * Check next arg to see if its a path. If it is not it must
	 * be a user name and we're in 4.3bsd compatibility mode.
	 */
	arg = skip(&cp);

	if(*arg != '/') {
		sep->se_user = strdup(arg);
		arg = skip(&cp);
	} else
		sep->se_user = NULL;

	sep->se_server = strdup(arg);
	argc = 0;
	for (arg = skip(&cp); cp; arg = skip(&cp))
		if (argc < MAXARGV)
			sep->se_argv[argc++] = strdup(arg);
	while (argc <= MAXARGV)
		sep->se_argv[argc++] = NULL;
	return (sep);
}

freeconfig(cp)
	register struct servtab *cp;
{
	int i;

	if (cp->se_service)
		free(cp->se_service);
	if (cp->se_proto)
		free(cp->se_proto);
	if (cp->se_server)
		free(cp->se_server);
	for (i = 0; i < MAXARGV; i++)
		if (cp->se_argv[i])
			free(cp->se_argv[i]);
}

char *
skip(cpp)
	char **cpp;
{
	register char *cp = *cpp;
	char *start;

again:
	while (*cp == ' ' || *cp == '\t')
		cp++;
	if (*cp == '\0') {
		char c;

		c = getc(fconfig);
		(void) ungetc(c, fconfig);
		if (c == ' ' || c == '\t')
			if (cp = nextline(fconfig))
				goto again;
		*cpp = (char *)0;
		return ((char *)0);
	}
	start = cp;
	while (*cp && *cp != ' ' && *cp != '\t')
		cp++;
	if (*cp != '\0')
		*cp++ = '\0';
	*cpp = cp;
	return (start);
}

char *
nextline(fd)
	FILE *fd;
{
	char *cp;

	if (fgets(line, sizeof (line), fd) == NULL)
		return ((char *)0);
	cp = index(line, '\n');
	if (cp)
		*cp = '\0';
	return (line);
}

char *
strdup(cp)
	char *cp;
{
	char *new;

	if (cp == NULL)
		cp = "";
	new = malloc(strlen(cp) + 1);
	if (new == (char *)0) {
		syslog(LOG_ERR, "Out of memory.");
		exit(-1);
	}
	(void) strcpy(new, cp);
	return (new);
}

anybit(field, count)
int *field;
int count;
{
	int index;

	for (index = 0; index < count; index++) {
		if (field[index] != 0) {
			return(-1);
		}
	}
	return(0);
}

pickbit(field, sbit)
int *field;
int sbit;
{
	field[sbit / (NBBY * NBPW)] |= 1 << (sbit % (NBBY * NBPW));
}

clearbit(field, cbit)
int *field;
int cbit;
{
	field[cbit / (NBBY * NBPW)] &= ~(1 << (cbit % (NBBY * NBPW)));
}