--- a/scpmisc.c	Sat Mar 25 12:57:09 2006 +0000
+++ b/scpmisc.c	Sat Mar 25 12:59:58 2006 +0000
@@ -140,12 +140,15 @@
 addargs(arglist *args, char *fmt, ...)
 {
 	va_list ap;
-	char buf[1024];
-	int nalloc;
+	char *cp;
+	u_int nalloc;
+	int r;
 
 	va_start(ap, fmt);
-	vsnprintf(buf, sizeof(buf), fmt, ap);
+	r = vasprintf(&cp, fmt, ap);
 	va_end(ap);
+	if (r == -1)
+		fatal("addargs: argument too long");
 
 	nalloc = args->nalloc;
 	if (args->list == NULL) {
@@ -156,6 +159,90 @@
 
 	args->list = xrealloc(args->list, nalloc * sizeof(char *));
 	args->nalloc = nalloc;
-	args->list[args->num++] = xstrdup(buf);
+	args->list[args->num++] = cp;
 	args->list[args->num] = NULL;
 }
+
+void
+replacearg(arglist *args, u_int which, char *fmt, ...)
+{
+	va_list ap;
+	char *cp;
+	int r;
+
+	va_start(ap, fmt);
+	r = vasprintf(&cp, fmt, ap);
+	va_end(ap);
+	if (r == -1)
+		fatal("replacearg: argument too long");
+
+	if (which >= args->num)
+		fatal("replacearg: tried to replace invalid arg %d >= %d",
+		    which, args->num);
+	xfree(args->list[which]);
+	args->list[which] = cp;
+}
+
+void
+freeargs(arglist *args)
+{
+	u_int i;
+
+	if (args->list != NULL) {
+		for (i = 0; i < args->num; i++)
+			xfree(args->list[i]);
+		xfree(args->list);
+		args->nalloc = args->num = 0;
+		args->list = NULL;
+	}
+}
+
+/*
+ * NB. duplicate __progname in case it is an alias for argv[0]
+ * Otherwise it may get clobbered by setproctitle()
+ */
+char *ssh_get_progname(char *argv0)
+{
+	char *p;
+
+	if (argv0 == NULL)
+		return ("unknown");	/* XXX */
+	p = strrchr(argv0, '/');
+	if (p == NULL)
+		p = argv0;
+	else
+		p++;
+
+	return (xstrdup(p));
+}
+
+void fatal(char* fmt,...)
+{
+	va_list args;
+	va_start(args, fmt);
+	vfprintf(stderr, fmt, args);
+	va_end(args);
+	exit(255);
+}
+
+void
+sanitise_stdfd(void)
+{
+	int nullfd, dupfd;
+
+	if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
+		fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
+		exit(1);
+	}
+	while (++dupfd <= 2) {
+		/* Only clobber closed fds */
+		if (fcntl(dupfd, F_GETFL, 0) >= 0)
+			continue;
+		if (dup2(nullfd, dupfd) == -1) {
+			fprintf(stderr, "dup2: %s", strerror(errno));
+			exit(1);
+		}
+	}
+	if (nullfd > 2)
+		close(nullfd);
+}