From 5328d8e7e8dbb968ba2aa83f98cf132a14266483 Mon Sep 17 00:00:00 2001 From: Karel Zak Date: Thu, 7 Sep 2017 11:23:50 +0200 Subject: su: (pty) simplify stdin usage in poll() Not sure why I have problem with this years ago for script(1), but it seems .fd=-1 is really enough to the ignore the FD. Reported-by: Vaclav Dolezal Signed-off-by: Karel Zak --- login-utils/su-common.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'login-utils') diff --git a/login-utils/su-common.c b/login-utils/su-common.c index f873c23bc..bc96967be 100644 --- a/login-utils/su-common.c +++ b/login-utils/su-common.c @@ -442,11 +442,11 @@ static int pty_handle_signal(struct su_context *su, int fd) static void pty_proxy_master(struct su_context *su) { sigset_t ourset; - int rc = 0, ret, ignore_stdin = 0, eof = 0; + int rc = 0, ret, eof = 0; enum { POLLFD_SIGNAL = 0, POLLFD_MASTER, - POLLFD_STDIN /* optional; keep it last, see ignore_stdin */ + POLLFD_STDIN }; struct pollfd pfd[] = { @@ -490,7 +490,7 @@ static void pty_proxy_master(struct su_context *su) DBG(PTY, ul_debug("calling poll()")); /* wait for input or signal */ - ret = poll(pfd, ARRAY_SIZE(pfd) - ignore_stdin, su->poll_timeout); + ret = poll(pfd, ARRAY_SIZE(pfd), su->poll_timeout); errsv = errno; DBG(PTY, ul_debug("poll() rc=%d", ret)); @@ -505,7 +505,7 @@ static void pty_proxy_master(struct su_context *su) break; } - for (i = 0; i < ARRAY_SIZE(pfd) - ignore_stdin; i++) { + for (i = 0; i < ARRAY_SIZE(pfd); i++) { rc = 0; if (pfd[i].revents == 0) @@ -531,10 +531,7 @@ static void pty_proxy_master(struct su_context *su) if ((pfd[i].revents & POLLHUP) || eof) { DBG(PTY, ul_debug(" ignore FD")); pfd[i].fd = -1; - /* according to man poll() set FD to -1 can't be used to ignore - * STDIN, so let's remove the FD from pool at all */ if (i == POLLFD_STDIN) { - ignore_stdin = 1; write_eof_to_child(su); DBG(PTY, ul_debug(" ignore STDIN")); } -- cgit v1.2.3-55-g7522