An upcoming patch needs to pass more than just sioc as the opaque
pointer to an AioContext; but since our AioContext code in general
(and its QIO Channel wrapper code) lacks a notify callback present
with GSource, we do not have the trivial option of just g_malloc'ing a
small struct to hold all that data coupled with a notify of g_free.
Instead, the data pointer must outlive the registered handler; in
fact, having the data pointer have the same lifetime as QIONetListener
is adequate.
But the cleanest way to stick such a helper struct in QIONetListener
will be to rearrange internal struct members. And that in turn means
that all existing code that currently directly accesses
listener->nsioc and listener->sioc[] should instead go through
accessor functions, to be immune to the upcoming struct layout
changes. So this patch adds accessor methods qio_net_listener_nsioc()
and qio_net_listener_sioc(), and puts them to use.
Signed-off-by: Eric Blake <eblake@redhat.com>
---
v2: new patch
---
include/io/net-listener.h | 24 ++++++++++++++++++++++++
chardev/char-socket.c | 3 ++-
io/net-listener.c | 12 ++++++++++++
migration/socket.c | 5 +++--
ui/vnc.c | 36 +++++++++++++++++++++++-------------
5 files changed, 64 insertions(+), 16 deletions(-)
diff --git a/include/io/net-listener.h b/include/io/net-listener.h
index 42fbfab5467..2605d6aae1e 100644
--- a/include/io/net-listener.h
+++ b/include/io/net-listener.h
@@ -184,4 +184,28 @@ void qio_net_listener_disconnect(QIONetListener *listener);
*/
bool qio_net_listener_is_connected(QIONetListener *listener);
+
+/**
+ * qio_net_listener_nsioc:
+ * @listener: the network listener object
+ *
+ * Determine the number of listener channels currently owned by the
+ * given listener.
+ *
+ * Returns: number of channels, or 0 if not listening
+ */
+size_t qio_net_listener_nsioc(QIONetListener *listener);
+
+
+/**
+ * qio_net_listener_sioc:
+ * @listener: the network listener object
+ * @n: index of the sioc to grab
+ *
+ * Accessor for the nth sioc owned by the listener.
+ *
+ * Returns: the requested listener, or #NULL if not in bounds
+ */
+QIOChannelSocket *qio_net_listener_sioc(QIONetListener *listener, size_t n);
+
#endif /* QIO_NET_LISTENER_H */
diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 62852e3caf5..022ae47d726 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -1255,7 +1255,8 @@ static int qmp_chardev_open_socket_server(Chardev *chr,
}
qapi_free_SocketAddress(s->addr);
- s->addr = socket_local_address(s->listener->sioc[0]->fd, errp);
+ s->addr = socket_local_address(qio_net_listener_sioc(s->listener, 0)->fd,
+ errp);
skip_listen:
update_disconnected_filename(s);
diff --git a/io/net-listener.c b/io/net-listener.c
index dd3522c9b3c..83c977ecca2 100644
--- a/io/net-listener.c
+++ b/io/net-listener.c
@@ -298,6 +298,18 @@ bool qio_net_listener_is_connected(QIONetListener *listener)
return listener->connected;
}
+size_t qio_net_listener_nsioc(QIONetListener *listener)
+{
+ return listener->nsioc;
+}
+
+QIOChannelSocket *qio_net_listener_sioc(QIONetListener *listener, size_t n)
+{
+ if (n > listener->nsioc) {
+ return NULL;
+ }
+ return listener->sioc[n];
+}
static void qio_net_listener_finalize(Object *obj)
{
QIONetListener *listener = QIO_NET_LISTENER(obj);
diff --git a/migration/socket.c b/migration/socket.c
index 5ec65b8c039..297de3ee156 100644
--- a/migration/socket.c
+++ b/migration/socket.c
@@ -170,9 +170,10 @@ void socket_start_incoming_migration(SocketAddress *saddr,
NULL, NULL,
g_main_context_get_thread_default());
- for (i = 0; i < listener->nsioc; i++) {
+ for (i = 0; i < qio_net_listener_nsioc(listener); i++) {
SocketAddress *address =
- qio_channel_socket_get_local_address(listener->sioc[i], errp);
+ qio_channel_socket_get_local_address(
+ qio_net_listener_sioc(listener, i), errp);
if (!address) {
return;
}
diff --git a/ui/vnc.c b/ui/vnc.c
index 50016ff7ab4..b5b6f5cd06f 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -235,12 +235,12 @@ static VncServerInfo *vnc_server_info_get(VncDisplay *vd)
VncServerInfo *info;
Error *err = NULL;
- if (!vd->listener || !vd->listener->nsioc) {
+ if (!vd->listener || !qio_net_listener_nsioc(vd->listener)) {
return NULL;
}
info = g_malloc0(sizeof(*info));
- vnc_init_basic_info_from_server_addr(vd->listener->sioc[0],
+ vnc_init_basic_info_from_server_addr(qio_net_listener_sioc(vd->listener, 0),
qapi_VncServerInfo_base(info), &err);
info->auth = g_strdup(vnc_auth_name(vd));
if (err) {
@@ -377,7 +377,7 @@ VncInfo *qmp_query_vnc(Error **errp)
VncDisplay *vd = vnc_display_find(NULL);
SocketAddress *addr = NULL;
- if (vd == NULL || !vd->listener || !vd->listener->nsioc) {
+ if (vd == NULL || !vd->listener || !qio_net_listener_nsioc(vd->listener)) {
info->enabled = false;
} else {
info->enabled = true;
@@ -386,8 +386,8 @@ VncInfo *qmp_query_vnc(Error **errp)
info->has_clients = true;
info->clients = qmp_query_client_list(vd);
- addr = qio_channel_socket_get_local_address(vd->listener->sioc[0],
- errp);
+ addr = qio_channel_socket_get_local_address(
+ qio_net_listener_sioc(vd->listener, 0), errp);
if (!addr) {
goto out_error;
}
@@ -549,6 +549,8 @@ VncInfo2List *qmp_query_vnc_servers(Error **errp)
size_t i;
QTAILQ_FOREACH(vd, &vnc_displays, next) {
+ size_t nsioc = 0;
+
info = g_new0(VncInfo2, 1);
info->id = g_strdup(vd->id);
info->clients = qmp_query_client_list(vd);
@@ -559,14 +561,21 @@ VncInfo2List *qmp_query_vnc_servers(Error **errp)
"device", &error_abort));
info->display = g_strdup(dev->id);
}
- for (i = 0; vd->listener != NULL && i < vd->listener->nsioc; i++) {
- info->server = qmp_query_server_entry(
- vd->listener->sioc[i], false, vd->auth, vd->subauth,
- info->server);
+ if (vd->listener != NULL) {
+ nsioc = qio_net_listener_nsioc(vd->listener);
}
- for (i = 0; vd->wslistener != NULL && i < vd->wslistener->nsioc; i++) {
+ for (i = 0; i < nsioc; i++) {
info->server = qmp_query_server_entry(
- vd->wslistener->sioc[i], true, vd->ws_auth,
+ qio_net_listener_sioc(vd->listener, i), false, vd->auth,
+ vd->subauth, info->server);
+ }
+ nsioc = 0;
+ if (vd->wslistener) {
+ nsioc = qio_net_listener_nsioc(vd->wslistener);
+ }
+ for (i = 0; i < nsioc; i++) {
+ info->server = qmp_query_server_entry(
+ qio_net_listener_sioc(vd->wslistener, i), true, vd->ws_auth,
vd->ws_subauth, info->server);
}
@@ -3550,11 +3559,12 @@ static void vnc_display_print_local_addr(VncDisplay *vd)
{
SocketAddress *addr;
- if (!vd->listener || !vd->listener->nsioc) {
+ if (!vd->listener || !qio_net_listener_nsioc(vd->listener)) {
return;
}
- addr = qio_channel_socket_get_local_address(vd->listener->sioc[0], NULL);
+ addr = qio_channel_socket_get_local_address(
+ qio_net_listener_sioc(vd->listener, 0), NULL);
if (!addr) {
return;
}
--
2.51.1On Sat, Nov 08, 2025 at 04:59:29PM -0600, Eric Blake wrote:
> An upcoming patch needs to pass more than just sioc as the opaque
> pointer to an AioContext; but since our AioContext code in general
> (and its QIO Channel wrapper code) lacks a notify callback present
> with GSource, we do not have the trivial option of just g_malloc'ing a
> small struct to hold all that data coupled with a notify of g_free.
> Instead, the data pointer must outlive the registered handler; in
> fact, having the data pointer have the same lifetime as QIONetListener
> is adequate.
>
> But the cleanest way to stick such a helper struct in QIONetListener
> will be to rearrange internal struct members. And that in turn means
> that all existing code that currently directly accesses
> listener->nsioc and listener->sioc[] should instead go through
> accessor functions, to be immune to the upcoming struct layout
> changes. So this patch adds accessor methods qio_net_listener_nsioc()
> and qio_net_listener_sioc(), and puts them to use.
>
> Signed-off-by: Eric Blake <eblake@redhat.com>
>
> ---
> v2: new patch
> ---
> include/io/net-listener.h | 24 ++++++++++++++++++++++++
> chardev/char-socket.c | 3 ++-
> io/net-listener.c | 12 ++++++++++++
> migration/socket.c | 5 +++--
> ui/vnc.c | 36 +++++++++++++++++++++++-------------
> 5 files changed, 64 insertions(+), 16 deletions(-)
>
> diff --git a/include/io/net-listener.h b/include/io/net-listener.h
> index 42fbfab5467..2605d6aae1e 100644
> --- a/include/io/net-listener.h
> +++ b/include/io/net-listener.h
> @@ -184,4 +184,28 @@ void qio_net_listener_disconnect(QIONetListener *listener);
> */
> bool qio_net_listener_is_connected(QIONetListener *listener);
>
> +
> +/**
> + * qio_net_listener_nsioc:
> + * @listener: the network listener object
> + *
> + * Determine the number of listener channels currently owned by the
> + * given listener.
> + *
> + * Returns: number of channels, or 0 if not listening
> + */
> +size_t qio_net_listener_nsioc(QIONetListener *listener);
> +
> +
> +/**
> + * qio_net_listener_sioc:
> + * @listener: the network listener object
> + * @n: index of the sioc to grab
> + *
> + * Accessor for the nth sioc owned by the listener.
> + *
> + * Returns: the requested listener, or #NULL if not in bounds
> + */
> +QIOChannelSocket *qio_net_listener_sioc(QIONetListener *listener, size_t n);
> +
> #endif /* QIO_NET_LISTENER_H */
> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> index 62852e3caf5..022ae47d726 100644
> --- a/chardev/char-socket.c
> +++ b/chardev/char-socket.c
> @@ -1255,7 +1255,8 @@ static int qmp_chardev_open_socket_server(Chardev *chr,
> }
>
> qapi_free_SocketAddress(s->addr);
> - s->addr = socket_local_address(s->listener->sioc[0]->fd, errp);
> + s->addr = socket_local_address(qio_net_listener_sioc(s->listener, 0)->fd,
> + errp);
Oh pre-existing bug / undesirable code pattern. This should be calling
qio_channel_socket_get_local_address, which avoids the needs to re-call
getsockname() as QIOChanelSocket has cached the local address.
Once we do that, then we would have 4 cases in this patch doing
qio_channel_socket_get_local_address(
qio_net_listener_sioc(listener, i), errp);
which would suggest adding a helper we could call as
qio_net_listener_get_local_address(listener, i, errp)
With regards,
Daniel
--
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|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On Sat, Nov 08, 2025 at 04:59:29PM -0600, Eric Blake wrote:
> An upcoming patch needs to pass more than just sioc as the opaque
> pointer to an AioContext; but since our AioContext code in general
> (and its QIO Channel wrapper code) lacks a notify callback present
> with GSource, we do not have the trivial option of just g_malloc'ing a
> small struct to hold all that data coupled with a notify of g_free.
> Instead, the data pointer must outlive the registered handler; in
> fact, having the data pointer have the same lifetime as QIONetListener
> is adequate.
>
> But the cleanest way to stick such a helper struct in QIONetListener
> will be to rearrange internal struct members. And that in turn means
> that all existing code that currently directly accesses
> listener->nsioc and listener->sioc[] should instead go through
> accessor functions, to be immune to the upcoming struct layout
> changes. So this patch adds accessor methods qio_net_listener_nsioc()
> and qio_net_listener_sioc(), and puts them to use.
>
> Signed-off-by: Eric Blake <eblake@redhat.com>
>
> ---
> +++ b/io/net-listener.c
> @@ -298,6 +298,18 @@ bool qio_net_listener_is_connected(QIONetListener *listener)
> return listener->connected;
> }
>
> +size_t qio_net_listener_nsioc(QIONetListener *listener)
> +{
> + return listener->nsioc;
> +}
> +
> +QIOChannelSocket *qio_net_listener_sioc(QIONetListener *listener, size_t n)
> +{
> + if (n > listener->nsioc) {
> + return NULL;
Off-by-1; this should be 'n >= listener->nsioc'.
> + }
> + return listener->sioc[n];
> +}
--
Eric Blake, Principal Software Engineer
Red Hat, Inc.
Virtualization: qemu.org | libguestfs.org
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