From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58413) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eNIoS-0002Go-Lf for qemu-devel@nongnu.org; Fri, 08 Dec 2017 08:35:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eNIoR-0002lW-Gq for qemu-devel@nongnu.org; Fri, 08 Dec 2017 08:35:36 -0500 Date: Fri, 8 Dec 2017 13:35:20 +0000 From: "Daniel P. Berrange" Message-ID: <20171208133520.GF11767@redhat.com> Reply-To: "Daniel P. Berrange" References: <20171206115726.5237-1-berrange@redhat.com> <20171208121521.GA2458@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20171208121521.GA2458@work-vm> Subject: Re: [Qemu-devel] [PATCH] qemu-io: fix EOF Ctrl-D handling in qemu-io readline code List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Dr. David Alan Gilbert" Cc: qemu-devel@nongnu.org, Kevin Wolf , Stefan Hajnoczi , qemu-block@nongnu.org, Max Reitz On Fri, Dec 08, 2017 at 12:15:21PM +0000, Dr. David Alan Gilbert wrote: > * Daniel P. Berrange (berrange@redhat.com) wrote: > > qemu-io puts the TTY into non-canonical mode, which means no EOF processing is > > done and thus getchar() will never return the EOF constant. Instead we have to > > check for an explicit Ctrl-D, aka 0x4, to detect EOF and exit the qemu-io > > shell. This fixes the regression that prevented Ctrl-D from triggering an exit > > of qemu-io that has existed since readline was first added in > > > > commit 0cf17e181798063c3824c8200ba46f25f54faa1a > > Author: Stefan Hajnoczi > > Date: Thu Nov 14 11:54:17 2013 +0100 > > > > qemu-io: use readline.c > > > > Signed-off-by: Daniel P. Berrange > > --- > > qemu-io.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/qemu-io.c b/qemu-io.c > > index c70bde3eb1..2ea0bfbaf8 100644 > > --- a/qemu-io.c > > +++ b/qemu-io.c > > @@ -322,7 +322,9 @@ static char *fetchline_readline(void) > > readline_start(readline_state, get_prompt(), 0, readline_func, &line); > > while (!line) { > > int ch = getchar(); > > - if (ch == EOF) { > > + /* In non-canon tty mode we get 0x4 (Ctrl-D), not the stdio "EOF" > > + * constant */ > > + if (ch == 0x4) { > > Personally I'd have made that EOF or 0x4 - but that's fine I thought about that, but it is impossible to get 'EOF' when the terminal is in raw mode, so there's little point. > (I don't see the point of reading the ioctl to figure out which EOF > char we're using; it seems to turn a trivial check into something much > more complex) I'd already done the work to read termios settings by time I read this comment, so I've sent a v2 anyway :-) > Reviewed-by: Dr. David Alan Gilbert Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|