[PULL 3/7] chardev/char-socket.c: Add yank feature

[Markus Armbruster <armbru@redhat.com>]

From: Lukas Straub <lukasstraub2@web.de>

Register a yank function to shutdown the socket on yank.

Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1f4eeed1d066c6cbb8d05ffa9585f6e87b34aac6.1609167865.git.lukasstraub2@web.de>
Acked-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 chardev/char-socket.c | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 213a4c8dd0..8a707d766c 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -34,6 +34,7 @@
 #include "qapi/error.h"
 #include "qapi/clone-visitor.h"
 #include "qapi/qapi-visit-sockets.h"
+#include "qemu/yank.h"
 
 #include "chardev/char-io.h"
 #include "qom/object.h"
@@ -70,6 +71,7 @@ struct SocketChardev {
     size_t read_msgfds_num;
     int *write_msgfds;
     size_t write_msgfds_num;
+    bool registered_yank;
 
     SocketAddress *addr;
     bool is_listen;
@@ -415,6 +417,12 @@ static void tcp_chr_free_connection(Chardev *chr)
 
     tcp_set_msgfds(chr, NULL, 0);
     remove_fd_in_watch(chr);
+    if (s->state == TCP_CHARDEV_STATE_CONNECTING
+        || s->state == TCP_CHARDEV_STATE_CONNECTED) {
+        yank_unregister_function(CHARDEV_YANK_INSTANCE(chr->label),
+                                 yank_generic_iochannel,
+                                 QIO_CHANNEL(s->sioc));
+    }
     object_unref(OBJECT(s->sioc));
     s->sioc = NULL;
     object_unref(OBJECT(s->ioc));
@@ -932,6 +940,9 @@ static int tcp_chr_add_client(Chardev *chr, int fd)
     }
     tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
     tcp_chr_set_client_ioc_name(chr, sioc);
+    yank_register_function(CHARDEV_YANK_INSTANCE(chr->label),
+                           yank_generic_iochannel,
+                           QIO_CHANNEL(sioc));
     ret = tcp_chr_new_client(chr, sioc);
     object_unref(OBJECT(sioc));
     return ret;
@@ -946,6 +957,9 @@ static void tcp_chr_accept(QIONetListener *listener,
 
     tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
     tcp_chr_set_client_ioc_name(chr, cioc);
+    yank_register_function(CHARDEV_YANK_INSTANCE(chr->label),
+                           yank_generic_iochannel,
+                           QIO_CHANNEL(cioc));
     tcp_chr_new_client(chr, cioc);
 }
 
@@ -961,6 +975,9 @@ static int tcp_chr_connect_client_sync(Chardev *chr, Error **errp)
         object_unref(OBJECT(sioc));
         return -1;
     }
+    yank_register_function(CHARDEV_YANK_INSTANCE(chr->label),
+                           yank_generic_iochannel,
+                           QIO_CHANNEL(sioc));
     tcp_chr_new_client(chr, sioc);
     object_unref(OBJECT(sioc));
     return 0;
@@ -976,6 +993,9 @@ static void tcp_chr_accept_server_sync(Chardev *chr)
     tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
     sioc = qio_net_listener_wait_client(s->listener);
     tcp_chr_set_client_ioc_name(chr, sioc);
+    yank_register_function(CHARDEV_YANK_INSTANCE(chr->label),
+                           yank_generic_iochannel,
+                           QIO_CHANNEL(sioc));
     tcp_chr_new_client(chr, sioc);
     object_unref(OBJECT(sioc));
 }
@@ -1086,6 +1106,9 @@ static void char_socket_finalize(Object *obj)
         object_unref(OBJECT(s->tls_creds));
     }
     g_free(s->tls_authz);
+    if (s->registered_yank) {
+        yank_unregister_instance(CHARDEV_YANK_INSTANCE(chr->label));
+    }
 
     qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
 }
@@ -1101,6 +1124,9 @@ static void qemu_chr_socket_connected(QIOTask *task, void *opaque)
 
     if (qio_task_propagate_error(task, &err)) {
         tcp_chr_change_state(s, TCP_CHARDEV_STATE_DISCONNECTED);
+        yank_unregister_function(CHARDEV_YANK_INSTANCE(chr->label),
+                                 yank_generic_iochannel,
+                                 QIO_CHANNEL(sioc));
         check_report_connect_error(chr, err);
         goto cleanup;
     }
@@ -1134,6 +1160,9 @@ static void tcp_chr_connect_client_async(Chardev *chr)
     tcp_chr_change_state(s, TCP_CHARDEV_STATE_CONNECTING);
     sioc = qio_channel_socket_new();
     tcp_chr_set_client_ioc_name(chr, sioc);
+    yank_register_function(CHARDEV_YANK_INSTANCE(chr->label),
+                           yank_generic_iochannel,
+                           QIO_CHANNEL(sioc));
     /*
      * Normally code would use the qio_channel_socket_connect_async
      * method which uses a QIOTask + qio_task_set_error internally
@@ -1376,6 +1405,11 @@ static void qmp_chardev_open_socket(Chardev *chr,
         qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_FD_PASS);
     }
 
+    if (!yank_register_instance(CHARDEV_YANK_INSTANCE(chr->label), errp)) {
+        return;
+    }
+    s->registered_yank = true;
+
     /* be isn't opened until we get a connection */
     *be_opened = false;
 
-- 
2.26.2