Set default emulator in domain_conf.*, rather than the driver.

Rather than numerous instances of:

emulator = vm->def->emulator;
if (!emulator)
    emulator = virDomainDefDefaultEmulator(conn, vm->def, driver->caps);
if (!emulator)
    return -1;

Set this value at XML parse time in the domain config, so we can depend on
it for all future emulator accesses. There were unchecked accesses in the
qemu driver that were tripping up on this if no emulator was specified in
the XML, see:

http://www.redhat.com/archives/libvir-list/2008-October/msg00602.html

ChangeLog

@@ -1,3 +1,9 @@
+Tue Jun 16 11:33:54 EDT 2009 Cole Robinson <crobinso@redhat.com>
+
+	* src/domain_conf.c src/domain_conf.h src/libvirt_private.syms
+	src/lxc_driver.c src/qemu_conf.c src/qemu_driver.c:
+	Set default emulator in domain_conf.*, rather than the driver.
+
 Tue Jun 16 11:18:00 EDT 2009 Cole Robinson <crobinso@redhat.com>
 
 	* src/capabilities.c src/capabilities.h src/libvirt_private.syms

src/domain_conf.c

@@ -2109,6 +2109,39 @@ int virDomainDiskQSort(const void *a, const void *b)
 }
 
 #ifndef PROXY
+static char *virDomainDefDefaultEmulator(virConnectPtr conn,
+                                         virDomainDefPtr def,
+                                         virCapsPtr caps) {
+    const char *type;
+    const char *emulator;
+    char *retemu;
+
+    type = virDomainVirtTypeToString(def->virtType);
+    if (!type) {
+        virDomainReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                             "%s", _("unknown virt type"));
+        return NULL;
+    }
+
+    emulator = virCapabilitiesDefaultGuestEmulator(caps,
+                                                   def->os.type,
+                                                   def->os.arch,
+                                                   type);
+
+    if (!emulator) {
+        virDomainReportError(conn, VIR_ERR_INTERNAL_ERROR,
+                             _("no emulator for domain %s os type %s on architecture %s"),
+                             type, def->os.type, def->os.arch);
+        return NULL;
+    }
+
+    retemu = strdup(emulator);
+    if (!retemu)
+        virReportOOMError(conn);
+
+    return retemu;
+}
+
 static virDomainDefPtr virDomainDefParseXML(virConnectPtr conn,
                                             virCapsPtr caps,
                                             xmlXPathContextPtr ctxt, int flags)
@@ -2358,6 +2391,11 @@ static virDomainDefPtr virDomainDefParseXML(virConnectPtr conn,
     }
 
     def->emulator = virXPathString(conn, "string(./devices/emulator[1])", ctxt);
+    if (!def->emulator && virCapabilitiesIsEmulatorRequired(caps)) {
+        def->emulator = virDomainDefDefaultEmulator(conn, def, caps);
+        if (!def->emulator)
+            goto error;
+    }
 
     /* analysis of the disk devices */
     if ((n = virXPathNodeSet(conn, "./devices/disk", ctxt, &nodes)) < 0) {
@@ -4230,34 +4268,6 @@ int virDiskNameToBusDeviceIndex(const virDomainDiskDefPtr disk,
     return 0;
 }
 
-const char *virDomainDefDefaultEmulator(virConnectPtr conn,
-                                        virDomainDefPtr def,
-                                        virCapsPtr caps) {
-    const char *type;
-    const char *emulator;
-
-    type = virDomainVirtTypeToString(def->virtType);
-    if (!type) {
-        virDomainReportError(conn, VIR_ERR_INTERNAL_ERROR,
-                             "%s", _("unknown virt type"));
-        return NULL;
-    }
-
-    emulator = virCapabilitiesDefaultGuestEmulator(caps,
-                                                   def->os.type,
-                                                   def->os.arch,
-                                                   type);
-
-    if (!emulator) {
-        virDomainReportError(conn, VIR_ERR_INTERNAL_ERROR,
-                             _("no emulator for domain %s os type %s on architecture %s"),
-                             type, def->os.type, def->os.arch);
-        return NULL;
-    }
-
-    return emulator;
-}
-
 virDomainFSDefPtr virDomainGetRootFilesystem(virDomainDefPtr def)
 {
     int i;

src/domain_conf.h

@@ -665,10 +665,6 @@ int virDiskNameToBusDeviceIndex(virDomainDiskDefPtr disk,
                                 int *busIdx,
                                 int *devIdx);
 
-const char *virDomainDefDefaultEmulator(virConnectPtr conn,
-                                        virDomainDefPtr def,
-                                        virCapsPtr caps);
-
 virDomainFSDefPtr virDomainGetRootFilesystem(virDomainDefPtr def);
 
 void virDomainObjLock(virDomainObjPtr obj);

src/libvirt_private.syms

@@ -65,7 +65,6 @@ virDomainCpuSetParse;
 virDomainChrDefFree;
 virDomainChrTypeFromString;
 virDomainChrTypeToString;
-virDomainDefDefaultEmulator;
 virDomainDefFormat;
 virDomainDefFree;
 virDomainDefParseFile;

src/lxc_driver.c

@@ -758,7 +758,6 @@ static int lxcControllerStart(virConnectPtr conn,
     fd_set keepfd;
     char appPtyStr[30];
     const char *emulator;
-    lxc_driver_t *driver = conn->privateData;
 
     FD_ZERO(&keepfd);
 
@@ -787,10 +786,6 @@ static int lxcControllerStart(virConnectPtr conn,
     snprintf(appPtyStr, sizeof(appPtyStr), "%d", appPty);
 
     emulator = vm->def->emulator;
-    if (!emulator)
-        emulator = virDomainDefDefaultEmulator(conn, vm->def, driver->caps);
-    if (!emulator)
-        return -1;
 
     ADD_ARG_LIT(emulator);
     ADD_ARG_LIT("--name");

src/qemu_conf.c

@@ -920,11 +920,6 @@ int qemudBuildCommandLine(virConnectPtr conn,
     }
 
     emulator = def->emulator;
-    if (!emulator)
-        emulator = virDomainDefDefaultEmulator(conn, def, driver->caps);
-    if (!emulator)
-        return -1;
-
 
     /* Need to explicitly disable KQEMU if
      * 1. Arch matches host arch

src/qemu_driver.c

@@ -1377,10 +1377,6 @@ static int qemudStartVMDaemon(virConnectPtr conn,
         goto cleanup;
 
     emulator = vm->def->emulator;
-    if (!emulator)
-        emulator = virDomainDefDefaultEmulator(conn, vm->def, driver->caps);
-    if (!emulator)
-        goto cleanup;
 
     /* Make sure the binary we are about to try exec'ing exists.
      * Technically we could catch the exec() failure, but that's
@@ -3425,10 +3421,6 @@ static char *qemuDomainXMLToNative(virConnectPtr conn,
             def->graphics[i]->data.vnc.port = 5900;
     }
     emulator = def->emulator;
-    if (!emulator)
-        emulator = virDomainDefDefaultEmulator(conn, def, driver->caps);
-    if (!emulator)
-        goto cleanup;
 
     /* Make sure the binary we are about to try exec'ing exists.
      * Technically we could catch the exec() failure, but that's