chsh: don't use empty shell field in /etc/passwd

chsh(1) uses empty shell setting (pw->pw_shell="") as a synonym for
/bin/sh. This convention is silly and unnecessary. (The vsftpd server
will not run if the shell assigned to user "ftp" is a null string --
according to bug rh#103004).

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/chsh.c b/login-utils/chsh.c
index add7c4395976d1ca5104decb6b53a41c151b35e6..15733a2c18b940260a5808d77fbff7f934613053 100644 (file)
--- a/login-utils/chsh.c
+++ b/login-utils/chsh.c
@@ -150,7 +150,8 @@ main (int argc, char *argv[]) {
 #endif
 
     oldshell = pw->pw_shell;
-    if (!oldshell[0]) oldshell = _PATH_BSHELL;
+    if (oldshell == NULL || *oldshell == '\0')
+           oldshell = _PATH_BSHELL;                    /* default */
 
     /* reality check */
     if (uid != 0 && uid != pw->pw_uid) {
@@ -219,7 +220,6 @@ main (int argc, char *argv[]) {
        printf (_("Shell not changed.\n"));
        return 0;
     }
-    if (!strcmp(shell, _PATH_BSHELL)) shell = "";
     pw->pw_shell = shell;
     if (setpwnam (pw) < 0) {
        perror ("setpwnam");
@@ -333,6 +333,9 @@ static int
 check_shell (char *shell) {
     int i, c;
 
+    if (!shell)
+       return (-1);
+
     if (*shell != '/') {
        printf (_("%s: shell must be a full path name.\n"), whoami);
        return (-1);