From 4bf1cb03fbc43b0055af60d4ff093d6894aa4338 Mon Sep 17 00:00:00 2001 From: Nils Carlson Date: Sun, 19 Jul 2015 20:39:56 +0000 Subject: [PATCH] qemu-char: Fix missed data on unix socket Commit 812c1057 introduced HUP detection on unix and tcp sockets prior to a read in tcp_chr_read. This unfortunately broke CloudStack 4.2 which relied on the old behaviour where data on a socket was readable even if a HUP was present. A working solution is to properly check the return values from recv, handling a closed socket once there is no more data to read. Also enable polling for G_IO_NVAL to ensure the callback is called for all possible events as these should now be possible to handle with the improved error detection. Signed-off-by: Nils Carlson Message-Id: <1437338396-22336-1-git-send-email-pyssling@ludd.ltu.se> [Do not handle EINTR; use socket_error(). - Paolo] Signed-off-by: Paolo Bonzini --- qemu-char.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index 3200200f0f..d956f8db6c 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -807,7 +807,8 @@ static gboolean io_watch_poll_prepare(GSource *source, gint *timeout_) } if (now_active) { - iwp->src = g_io_create_watch(iwp->channel, G_IO_IN | G_IO_ERR | G_IO_HUP); + iwp->src = g_io_create_watch(iwp->channel, + G_IO_IN | G_IO_ERR | G_IO_HUP | G_IO_NVAL); g_source_set_callback(iwp->src, iwp->fd_read, iwp->opaque, NULL); g_source_attach(iwp->src, NULL); } else { @@ -2856,12 +2857,6 @@ static gboolean tcp_chr_read(GIOChannel *chan, GIOCondition cond, void *opaque) uint8_t buf[READ_BUF_LEN]; int len, size; - if (cond & G_IO_HUP) { - /* connection closed */ - tcp_chr_disconnect(chr); - return TRUE; - } - if (!s->connected || s->max_size <= 0) { return TRUE; } @@ -2869,7 +2864,9 @@ static gboolean tcp_chr_read(GIOChannel *chan, GIOCondition cond, void *opaque) if (len > s->max_size) len = s->max_size; size = tcp_chr_recv(chr, (void *)buf, len); - if (size == 0) { + if (size == 0 || + (size < 0 && + socket_error() != EAGAIN && socket_error() != EWOULDBLOCK)) { /* connection closed */ tcp_chr_disconnect(chr); } else if (size > 0) {