qemu: command: escape commas in VNC socket path

This path can be dependent on the VM libdir, which contains its name

src/qemu/qemu_command.c

@@ -7425,7 +7425,8 @@ qemuBuildGraphicsVNCCommandLine(virQEMUDriverConfigPtr cfg,
             graphics->data.vnc.socketAutogenerated = true;
         }
 
-        virBufferAsprintf(&opt, "unix:%s", graphics->data.vnc.socket);
+        virBufferAddLit(&opt, "unix:");
+        qemuBufferEscapeComma(&opt, graphics->data.vnc.socket);
 
     } else {
         if (!graphics->data.vnc.autoport &&

tests/qemuxml2argvdata/qemuxml2argv-name-escape.args

@@ -13,7 +13,6 @@ bar/master-key.aes \
 -m 214 \
 -smp 1 \
 -uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
--nographic \
 -nodefaults \
 -chardev socket,id=charmonitor,path=/tmp/lib/domain--1-foo,bar/monitor.sock,\
 server,nowait \
@@ -21,4 +20,6 @@ server,nowait \
 -no-acpi \
 -boot c \
 -usb \
+-vnc unix:/tmp/bar,,foo.sock \
+-vga cirrus \
 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

tests/qemuxml2argvdata/qemuxml2argv-name-escape.xml

@@ -14,5 +14,6 @@
   <on_crash>destroy</on_crash>
   <devices>
     <emulator>/usr/bin/qemu</emulator>
+    <graphics type='vnc' socket='/tmp/bar,foo.sock'/>
   </devices>
 </domain>

tests/qemuxml2argvtest.c

@@ -1903,7 +1903,7 @@ mymain(void)
                               NONE);
 
     DO_TEST("name-escape", QEMU_CAPS_NAME_DEBUG_THREADS,
-            QEMU_CAPS_OBJECT_SECRET, QEMU_CAPS_CHARDEV);
+            QEMU_CAPS_OBJECT_SECRET, QEMU_CAPS_CHARDEV, QEMU_CAPS_VNC);
     DO_TEST("debug-threads", QEMU_CAPS_NAME_DEBUG_THREADS);
 
     DO_TEST("master-key", QEMU_CAPS_OBJECT_SECRET);