treewide: handle result of qio_channel_set_blocking()

Currently, we just always pass NULL as errp argument. That doesn't
look good.

Some realizations of interface may actually report errors.
Channel-socket realization actually either ignore or crash on
errors, but we are going to straighten it out to always reporting
an errp in further commits.

So, convert all callers to either handle the error (where environment
allows) or explicitly use &error_abort.

Take also a chance to change the return value to more convenient
bool (keeping also in mind, that underlying realizations may
return -1 on failure, not -errno).

Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
[DB: fix return type mismatch in TLS/websocket channel
     impls for qio_channel_set_blocking]
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

1 files changed, 16 insertions, 4 deletions

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 1be078dfc0..cb4ec78ebe 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -530,16 +530,24 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len)
     SocketChardev *s = SOCKET_CHARDEV(chr);
     int size;
     int saved_errno;
+    Error *local_err = NULL;
 
     if (s->state != TCP_CHARDEV_STATE_CONNECTED) {
         return 0;
     }
 
-    qio_channel_set_blocking(s->ioc, true, NULL);
+    if (!qio_channel_set_blocking(s->ioc, true, &local_err)) {
+        error_report_err(local_err);
+        return -1;
+    }
     size = tcp_chr_recv(chr, (void *) buf, len);
     saved_errno = errno;
     if (s->state != TCP_CHARDEV_STATE_DISCONNECTED) {
-        qio_channel_set_blocking(s->ioc, false, NULL);
+        if (!qio_channel_set_blocking(s->ioc, false, &local_err)) {
+            error_report_err(local_err);
+            /* failed to recover non-blocking state */
+            tcp_chr_disconnect(chr);
+        }
     }
     if (size == 0) {
         /* connection closed */
@@ -884,18 +892,22 @@ static void tcp_chr_set_client_ioc_name(Chardev *chr,
 static int tcp_chr_new_client(Chardev *chr, QIOChannelSocket *sioc)
 {
     SocketChardev *s = SOCKET_CHARDEV(chr);
+    Error *local_err = NULL;
 
     if (s->state != TCP_CHARDEV_STATE_CONNECTING) {
         return -1;
     }
 
+    if (!qio_channel_set_blocking(QIO_CHANNEL(sioc), false, &local_err)) {
+        error_report_err(local_err);
+        return -1;
+    }
+
     s->ioc = QIO_CHANNEL(sioc);
     object_ref(OBJECT(sioc));
     s->sioc = sioc;
     object_ref(OBJECT(sioc));
 
-    qio_channel_set_blocking(s->ioc, false, NULL);
-
     if (s->do_nodelay) {
         qio_channel_set_delay(s->ioc, false);
     }