From: Marc-André Lureau <marcandre.lureau@redhat.com>
Date: Fri, 11 Mar 2016 17:55:24 +0000 (+0100)
Subject: char: translate from QIOChannel error to errno
X-Git-Tag: v2.6.0-rc0~9^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b6572b4f97a7b126c7b24e165893ed9fe3d72e1f;p=thirdparty%2Fqemu.git

char: translate from QIOChannel error to errno

Caller of CharDriverState.chr* callback assume errno error conventions.
Translate QIOChannel error to errno (this fixes potential EAGAIN
regression, for ex if a vhost-user backend block, qemu_chr_fe_read_all()
could get error -2 and not wait)

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1457718924-19338-1-git-send-email-marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---

diff --git a/qemu-char.c b/qemu-char.c
index 97aaaae4390..270819aec35 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -2799,6 +2799,13 @@ static ssize_t tcp_chr_recv(CharDriverState *chr, char *buf, size_t len)
                                      NULL);
     }
 
+    if (ret == QIO_CHANNEL_ERR_BLOCK) {
+        errno = EAGAIN;
+        ret = -1;
+    } else if (ret == -1) {
+        errno = EIO;
+    }
+
     if (msgfds_num) {
         /* close and clean read_msgfds */
         for (i = 0; i < s->read_msgfds_num; i++) {