graphics: Cleanup port policy

Even though we say in documentation setting (tls-)port to -1 is legacy
compat style for enabling autoport, we're roughly doing this for VNC.
However, in case of SPICE auto enable autoport iff both port & tlsPort
are equal -1 as documentation says autoport plays with both.

src/conf/domain_conf.c

@@ -5929,6 +5929,10 @@ virDomainGraphicsDefParseXML(xmlNodePtr node,
                 VIR_FREE(port);
                 goto error;
             }
+            /* Legacy compat syntax, used -1 for auto-port */
+            if (def->data.rdp.port == -1)
+                def->data.rdp.autoport = 1;
+
             VIR_FREE(port);
         } else {
             def->data.rdp.port = 0;
@@ -5936,14 +5940,15 @@ virDomainGraphicsDefParseXML(xmlNodePtr node,
         }
 
         if ((autoport = virXMLPropString(node, "autoport")) != NULL) {
-            if (STREQ(autoport, "yes")) {
-                if (flags & VIR_DOMAIN_XML_INACTIVE)
-                    def->data.rdp.port = 0;
+            if (STREQ(autoport, "yes"))
                 def->data.rdp.autoport = 1;
-            }
+
             VIR_FREE(autoport);
         }
 
+        if (def->data.rdp.autoport && (flags & VIR_DOMAIN_XML_INACTIVE))
+            def->data.rdp.port = 0;
+
         if ((replaceUser = virXMLPropString(node, "replaceUser")) != NULL) {
             if (STREQ(replaceUser, "yes")) {
                 def->data.rdp.replaceUser = 1;
@@ -6009,14 +6014,19 @@ virDomainGraphicsDefParseXML(xmlNodePtr node,
         }
 
         if ((autoport = virXMLPropString(node, "autoport")) != NULL) {
-            if (STREQ(autoport, "yes")) {
-                if (flags & VIR_DOMAIN_XML_INACTIVE) {
-                    def->data.spice.port = 0;
-                    def->data.spice.tlsPort = 0;
+            if (STREQ(autoport, "yes"))
+                def->data.spice.autoport = 1;
+            VIR_FREE(autoport);
         }
+
+        if (def->data.spice.port == -1 && def->data.spice.tlsPort == -1) {
+            /* Legacy compat syntax, used -1 for auto-port */
             def->data.spice.autoport = 1;
         }
-            VIR_FREE(autoport);
+
+        if (def->data.spice.autoport && (flags & VIR_DOMAIN_XML_INACTIVE)) {
+            def->data.spice.port = 0;
+            def->data.spice.tlsPort = 0;
         }
 
         def->data.spice.keymap = virXMLPropString(node, "keymap");

src/conf/domain_conf.h

@@ -1183,6 +1183,11 @@ struct _virDomainGraphicsListenDef {
 };
 
 struct _virDomainGraphicsDef {
+    /* Port value discipline:
+     * Value -1 is legacy syntax indicating that it should be auto-allocated.
+     * Value 0 means port wasn't specified in XML at all.
+     * Positive value is actual port number given in XML.
+     */
     int type;
     union {
         struct {

src/qemu/qemu_command.c

@@ -5379,7 +5379,7 @@ qemuBuildCommandLine(virConnectPtr conn,
 
         virBufferAsprintf(&opt, "port=%u", def->graphics[0]->data.spice.port);
 
-        if (def->graphics[0]->data.spice.tlsPort) {
+        if (def->graphics[0]->data.spice.tlsPort > 0) {
             if (!driver->spiceTLS) {
                 qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                                 _("spice TLS port set in XML configuration,"

src/qemu/qemu_process.c

@@ -3169,30 +3169,37 @@ int qemuProcessStart(virConnectPtr conn,
                 goto cleanup;
             }
             vm->def->graphics[0]->data.vnc.port = port;
-        } else if (vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SPICE &&
-                   vm->def->graphics[0]->data.spice.autoport) {
-            int port = qemuProcessNextFreePort(driver, QEMU_VNC_PORT_MIN);
-            int tlsPort = -1;
+        } else if (vm->def->graphics[0]->type == VIR_DOMAIN_GRAPHICS_TYPE_SPICE) {
+            int port = -1;
+            if (vm->def->graphics[0]->data.spice.autoport ||
+                vm->def->graphics[0]->data.spice.port == -1) {
+                port = qemuProcessNextFreePort(driver, QEMU_VNC_PORT_MIN);
+
                 if (port < 0) {
                     qemuReportError(VIR_ERR_INTERNAL_ERROR,
                                     "%s", _("Unable to find an unused SPICE port"));
                     goto cleanup;
                 }
 
-            if (driver->spiceTLS) {
-                tlsPort = qemuProcessNextFreePort(driver, port + 1);
+                vm->def->graphics[0]->data.spice.port = port;
+            }
+
+            if (driver->spiceTLS &&
+                (vm->def->graphics[0]->data.spice.autoport ||
+                 vm->def->graphics[0]->data.spice.tlsPort == -1)) {
+                int tlsPort = qemuProcessNextFreePort(driver,
+                                                      vm->def->graphics[0]->data.spice.port + 1);
                 if (tlsPort < 0) {
                     qemuReportError(VIR_ERR_INTERNAL_ERROR,
                                     "%s", _("Unable to find an unused SPICE TLS port"));
                     qemuProcessReturnPort(driver, port);
                     goto cleanup;
                 }
-            }
 
-            vm->def->graphics[0]->data.spice.port = port;
                 vm->def->graphics[0]->data.spice.tlsPort = tlsPort;
             }
         }
+    }
 
     if (virFileMakePath(driver->logDir) < 0) {
         virReportSystemError(errno,