qemu: Do fake auto-allocation of ports when generating native command

When attempting to generate the native command line from an XML file
that uses graphics port auto allocation, the generated commandline
wouldn't be valid.

This patch adds fake autoallocation of ports as done when starting the
actual machine.

src/qemu/qemu_driver.c

@@ -5274,6 +5274,58 @@ static char *qemuConnectDomainXMLToNative(virConnectPtr conn,
     if (qemuDomainAssignAddresses(def, qemuCaps, NULL) < 0)
         goto cleanup;
 
+    /* do fake auto-alloc of graphics ports, if such config is used */
+    for (i = 0 ; i < def->ngraphics; ++i) {
+        virDomainGraphicsDefPtr graphics = def->graphics[i];
+        if (graphics->type == VIR_DOMAIN_GRAPHICS_TYPE_VNC &&
+            !graphics->data.vnc.socket && graphics->data.vnc.autoport) {
+            graphics->data.vnc.port = 5900;
+        } else if (graphics->type == VIR_DOMAIN_GRAPHICS_TYPE_SPICE) {
+            int j;
+            bool needTLSPort = false;
+            bool needPort = false;
+            int defaultMode = graphics->data.spice.defaultMode;
+
+            if (graphics->data.spice.autoport) {
+                /* check if tlsPort or port need allocation */
+                for (j = 0 ; j < VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_LAST ; j++) {
+                    switch (graphics->data.spice.channels[j]) {
+                    case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_SECURE:
+                        needTLSPort = true;
+                        break;
+
+                    case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_INSECURE:
+                        needPort = true;
+                        break;
+
+                    case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_ANY:
+                        switch (defaultMode) {
+                        case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_SECURE:
+                            needTLSPort = true;
+                            break;
+
+                        case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_INSECURE:
+                            needPort = true;
+                            break;
+
+                        case VIR_DOMAIN_GRAPHICS_SPICE_CHANNEL_MODE_ANY:
+                            needTLSPort = true;
+                            needPort = true;
+                            break;
+                        }
+                        break;
+                    }
+                }
+            }
+
+            if (needPort || graphics->data.spice.port == -1)
+                graphics->data.spice.port = 5901;
+
+            if (needTLSPort || graphics->data.spice.tlsPort == -1)
+                graphics->data.spice.tlsPort = 5902;
+        }
+    }
+
     if (!(cmd = qemuBuildCommandLine(conn, driver, def,
                                      &monConfig, monitor_json, qemuCaps,
                                      NULL, -1, NULL, VIR_NETDEV_VPORT_PROFILE_OP_NO_OP)))