conf: Introduce virStoragePoolXMLNamespace

Introduce the infrastructure necessary to manage a Storage Pool XML
Namespace. The general concept is similar to virDomainXMLNamespace,
except that for Storage Pools the storage backend specific details
can be stored within the _virStoragePoolOptions unlike the domain
processing code which manages its xmlopt's via the virDomainXMLOption
which is allocated/passed around for each domain.

This patch defines the add the parse, format, free, and href methods
required to process the XML and callout from the Storage Pool Def
parse, format, and free API's to perform the action on the XML data
for/from the backend.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

src/conf/storage_conf.c

@@ -124,6 +124,9 @@ typedef virStoragePoolOptions *virStoragePoolOptionsPtr;
 struct _virStoragePoolOptions {
     unsigned int flags;
     int defaultFormat;
+
+    virStoragePoolXMLNamespace ns;
+
     virStoragePoolFormatToString formatToString;
     virStoragePoolFormatFromString formatFromString;
 };
@@ -318,6 +321,34 @@ virStoragePoolOptionsForPoolType(int type)
 }
 
 
+/* virStoragePoolOptionsPoolTypeSetXMLNamespace:
+ * @type: virStoragePoolType
+ * @ns: xmlopt namespace pointer
+ *
+ * Store the @ns in the pool options for the particular backend.
+ * This allows the parse/format code to then directly call the Namespace
+ * method space (parse, format, href, free) as needed during processing.
+ *
+ * Returns: 0 on success, -1 on failure.
+ */
+int
+virStoragePoolOptionsPoolTypeSetXMLNamespace(int type,
+                                             virStoragePoolXMLNamespacePtr ns)
+{
+    int ret = -1;
+    virStoragePoolTypeInfoPtr backend = virStoragePoolTypeInfoLookup(type);
+
+    if (!backend)
+        goto cleanup;
+
+    backend->poolOptions.ns = *ns;
+    ret = 0;
+
+ cleanup:
+    return ret;
+}
+
+
 static virStorageVolOptionsPtr
 virStorageVolOptionsForPoolType(int type)
 {
@@ -401,6 +432,8 @@ virStoragePoolDefFree(virStoragePoolDefPtr def)
 
     VIR_FREE(def->target.path);
     VIR_FREE(def->target.perms.label);
+    if (def->namespaceData && def->ns.free)
+        (def->ns.free)(def->namespaceData);
     VIR_FREE(def);
 }
 
@@ -834,6 +867,13 @@ virStoragePoolDefParseXML(xmlXPathContextPtr ctxt)
         goto error;
     }
 
+    /* Make a copy of all the callback pointers here for easier use,
+     * especially during the virStoragePoolSourceClear method */
+    ret->ns = options->ns;
+    if (ret->ns.parse &&
+        (ret->ns.parse)(ctxt, &ret->namespaceData) < 0)
+        goto error;
+
  cleanup:
     VIR_FREE(uuid);
     VIR_FREE(type);
@@ -1010,7 +1050,10 @@ virStoragePoolDefFormatBuf(virBufferPtr buf,
                        _("unexpected pool type"));
         return -1;
     }
-    virBufferAsprintf(buf, "<pool type='%s'>\n", type);
+    virBufferAsprintf(buf, "<pool type='%s'", type);
+    if (def->namespaceData && def->ns.href)
+        virBufferAsprintf(buf, " %s", (def->ns.href)());
+    virBufferAddLit(buf, ">\n");
     virBufferAdjustIndent(buf, 2);
     virBufferEscapeString(buf, "<name>%s</name>\n", def->name);
 
@@ -1063,6 +1106,12 @@ virStoragePoolDefFormatBuf(virBufferPtr buf,
         virBufferAdjustIndent(buf, -2);
         virBufferAddLit(buf, "</target>\n");
     }
+
+    if (def->namespaceData && def->ns.format) {
+        if ((def->ns.format)(buf, def->namespaceData) < 0)
+            return -1;
+    }
+
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</pool>\n");
 

src/conf/storage_conf.h

@@ -33,6 +33,26 @@
 
 # include <libxml/tree.h>
 
+/* Various callbacks needed to parse/create Storage Pool XML's using
+ * a private namespace */
+typedef int (*virStoragePoolDefNamespaceParse)(xmlXPathContextPtr, void **);
+typedef void (*virStoragePoolDefNamespaceFree)(void *);
+typedef int (*virStoragePoolDefNamespaceXMLFormat)(virBufferPtr, void *);
+typedef const char *(*virStoragePoolDefNamespaceHref)(void);
+
+typedef struct _virStoragePoolXMLNamespace virStoragePoolXMLNamespace;
+typedef virStoragePoolXMLNamespace *virStoragePoolXMLNamespacePtr;
+struct _virStoragePoolXMLNamespace {
+    virStoragePoolDefNamespaceParse parse;
+    virStoragePoolDefNamespaceFree free;
+    virStoragePoolDefNamespaceXMLFormat format;
+    virStoragePoolDefNamespaceHref href;
+};
+
+int
+virStoragePoolOptionsPoolTypeSetXMLNamespace(int type,
+                                             virStoragePoolXMLNamespacePtr ns);
+
 /*
  * How the volume's data is stored on underlying
  * physical devices - can potentially span many
@@ -222,6 +242,10 @@ struct _virStoragePoolDef {
 
     virStoragePoolSource source;
     virStoragePoolTarget target;
+
+    /* Pool backend specific XML namespace data */
+    void *namespaceData;
+    virStoragePoolXMLNamespace ns;
 };
 
 typedef struct _virStoragePoolSourceList virStoragePoolSourceList;

src/libvirt_private.syms

@@ -921,6 +921,7 @@ virStoragePoolFormatDiskTypeToString;
 virStoragePoolFormatFileSystemNetTypeToString;
 virStoragePoolFormatFileSystemTypeToString;
 virStoragePoolFormatLogicalTypeToString;
+virStoragePoolOptionsPoolTypeSetXMLNamespace;
 virStoragePoolSaveConfig;
 virStoragePoolSaveState;
 virStoragePoolSourceClear;