Commit 12fb0ac0 authored May 23, 2018 by Patryk Olszewski Committed by Paolo Bonzini Jun 01, 2018

char: Remove unwanted crlf conversion

This patch fixes a bug in serial that made it almost impossible for guest
to communicate with devices through host's serial.

OPOST flag in c_oflag enables output processing letting other flags in
c_oflag take effect. Usually in c_oflag ONLCR flag is also set, which
causes crlf to be sent in place of lf. This breaks binary transmissions.
Unsetting OPOST flag turns off any output processing which fixes the bug.

Bug reports related:
https://bugs.launchpad.net/qemu/+bug/1772086
https://bugs.launchpad.net/qemu/+bug/1407813
https://bugs.launchpad.net/qemu/+bug/1715296
also
https://lists.nongnu.org/archive/html/qemu-devel/2006-06/msg00196.html



Signed-off-by: Patryk Olszewski <patryk@fala.ehost.pl>
Message-Id: <1527105041-21013-1-git-send-email-patryk@fala.ehost.pl>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent ff46d9d4

chardev/char-serial.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -139,7 +139,7 @@ static void tty_serial_init(int fd, int speed,

		tty.c_iflag &= ~(IGNBRK \| BRKINT \| PARMRK \| ISTRIP
		\| INLCR \| IGNCR \| ICRNL \| IXON);
		tty.c_oflag \|= OPOST;
		tty.c_oflag &= ~OPOST;
		tty.c_lflag &= ~(ECHO \| ECHONL \| ICANON \| IEXTEN \| ISIG);
		tty.c_cflag &= ~(CSIZE \| PARENB \| PARODD \| CRTSCTS \| CSTOPB);
		switch (data_bits) {

chardev/char-stdio.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -59,7 +59,7 @@ static void qemu_chr_set_echo_stdio(Chardev *chr, bool echo)
		if (!echo) {
		tty.c_iflag &= ~(IGNBRK \| BRKINT \| PARMRK \| ISTRIP
		\| INLCR \| IGNCR \| ICRNL \| IXON);
		tty.c_oflag \|= OPOST;
		tty.c_oflag &= ~OPOST;
		tty.c_lflag &= ~(ECHO \| ECHONL \| ICANON \| IEXTEN);
		tty.c_cflag &= ~(CSIZE \| PARENB);
		tty.c_cflag \|= CS8;