tools: kwboot: Disable non-blocking mode
The kwboot utility does not handle EAGAIN / EBUSY errors, it expects
blocking mode on tty - it uses select() to check if data is available.
Disable non-blocking mode by clearing O_NDELAY flag which was set by
open().
We can't just take O_NDELAY from open(), because it is required there
until the CLOCAL flag is set on the tty.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <marek.behun@nic.cz>
diff --git a/tools/kwboot.c b/tools/kwboot.c
index a527c79..5e491f3 100644
--- a/tools/kwboot.c
+++ b/tools/kwboot.c
@@ -639,7 +639,7 @@
static int
kwboot_open_tty(const char *path, int baudrate)
{
- int rc, fd;
+ int rc, fd, flags;
struct termios tio;
rc = -1;
@@ -661,6 +661,14 @@
if (rc)
goto out;
+ flags = fcntl(fd, F_GETFL);
+ if (flags < 0)
+ goto out;
+
+ rc = fcntl(fd, F_SETFL, flags & ~O_NDELAY);
+ if (rc)
+ goto out;
+
rc = kwboot_tty_change_baudrate(fd, baudrate);
if (rc)
goto out;