From 060ed82ec24d942c5f519e3dae45e9e2bfb227d8 Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Sun, 13 Feb 2011 17:09:29 +0100 Subject: systemctl: don't unnecessarily close stdin/stdout/stderr for tty agent so that locking by tty works --- src/systemctl.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) (limited to 'src') diff --git a/src/systemctl.c b/src/systemctl.c index c09b31d1df..94a12ddeb2 100644 --- a/src/systemctl.c +++ b/src/systemctl.c @@ -121,7 +121,7 @@ static bool on_tty(void) { /* Note that this is invoked relatively early, before we start * the pager. That means the value we return reflects whether * we originally were started on a tty, not if we currently - * are. But this is intended, since we want color, and so on + * are. But this is intended, since we want colour and so on * when run in our own pager. */ if (_unlikely_(t < 0)) @@ -174,27 +174,32 @@ static void spawn_ask_password_agent(void) { /* Don't leak fds to the agent */ close_all_fds(NULL, 0); - /* Detach from stdin/stdout/stderr. and reopen - * /dev/tty for them. This is important to ensure that - * when systemctl is started via popen() or a similar - * call that expects to read EOF we actually do - * generate EOF and not delay this indefinitely by - * because we keep an unused copy of stdin around. */ - if ((fd = open("/dev/tty", O_RDWR)) < 0) { - log_error("Failed to open /dev/tty: %m"); - _exit(EXIT_FAILURE); - } + if (!isatty(STDOUT_FILENO) || !isatty(STDERR_FILENO)) { + /* Detach from stdout/stderr. and reopen + * /dev/tty for them. This is important to + * ensure that when systemctl is started via + * popen() or a similar call that expects to + * read EOF we actually do generate EOF and + * not delay this indefinitely by because we + * keep an unused copy of stdin around. */ + if ((fd = open("/dev/tty", O_WRONLY)) < 0) { + log_error("Failed to open /dev/tty: %m"); + _exit(EXIT_FAILURE); + } - close(STDIN_FILENO); - close(STDOUT_FILENO); - close(STDERR_FILENO); + if (!isatty(STDOUT_FILENO)) { + close(STDOUT_FILENO); + dup2(fd, STDOUT_FILENO); + } - dup2(fd, STDIN_FILENO); - dup2(fd, STDOUT_FILENO); - dup2(fd, STDERR_FILENO); + if (!isatty(STDERR_FILENO)) { + close(STDERR_FILENO); + dup2(fd, STDERR_FILENO); + } - if (fd > 2) - close(fd); + if (fd > 2) + close(fd); + } execv(args[0], (char **) args); _exit(EXIT_FAILURE); -- cgit v1.2.3-54-g00ecf