Ignore default-shell (and use /bin/sh) if it invalid not just if it is

tmux itself, also refuse to set the option to something invalid in the
first place. GitHub issue 2120.

1 files changed, 3 insertions, 3 deletions

diff --git a/tmux.c b/tmux.c
index 572e705c..60b35e5d 100644
--- a/tmux.c
+++ b/tmux.c
@@ -49,8 +49,8 @@ const char	*shell_command;
 static __dead void	 usage(void);
 static char		*make_label(const char *, char **);
 
+static int		 areshell(const char *);
 static const char	*getshell(void);
-static int		 checkshell(const char *);
 
 static __dead void
 usage(void)
@@ -79,7 +79,7 @@ getshell(void)
 	return (_PATH_BSHELL);
 }
 
-static int
+int
 checkshell(const char *shell)
 {
 	if (shell == NULL || *shell != '/')
@@ -91,7 +91,7 @@ checkshell(const char *shell)
 	return (1);
 }
 
-int
+static int
 areshell(const char *shell)
 {
 	const char	*progname, *ptr;