If multiple arguments are given to new-session, new-window,

split-window, respawn-window or respawn-pane, pass them directly to
execvp() to help avoid quoting problems. One argument still goes to "sh
-c" like before. Requested by many over the years. Patch from J Raynor.

cmd.c

@@ -187,7 +187,7 @@ cmd_copy_argv(int argc, char **argv)
 
 	if (argc == 0)
 		return (NULL);
-	new_argv = xcalloc(argc, sizeof *new_argv);
+	new_argv = xcalloc(argc + 1, sizeof *new_argv);
 	for (i = 0; i < argc; i++) {
 		if (argv[i] != NULL)
 			new_argv[i] = xstrdup(argv[i]);
@@ -207,6 +207,32 @@ cmd_free_argv(int argc, char **argv)
 	free(argv);
 }
 
+char *
+cmd_stringify_argv(int argc, char **argv)
+{
+	char	*buf;
+	int	 i;
+	size_t	 len;
+
+	if (argc == 0)
+		return (xstrdup(""));
+
+	len = 0;
+	buf = NULL;
+
+	for (i = 0; i < argc; i++) {
+		len += strlen(argv[i]) + 1;
+		buf = xrealloc(buf, 1, len);
+
+		if (i == 0)
+			*buf = '\0';
+		else
+			strlcat(buf, " ", len);
+		strlcat(buf, argv[i], len);
+	}
+	return (buf);
+}
+
 struct cmd *
 cmd_parse(int argc, char **argv, const char *file, u_int line, char **cause)
 {