From 25d339a412b1a3d3436d3ff3c9ed63139c8f2428 Mon Sep 17 00:00:00 2001

Message-Id: <25d339a412b1a3d3436d3ff3c9ed63139c8f2428@dist-git>

From: Peter Krempa <pkrempa@redhat.com>

Date: Thu, 22 Jan 2015 15:53:45 +0100

Subject: [PATCH] conf: Add support for requesting of XML metadata via the API

https://bugzilla.redhat.com/show_bug.cgi?id=1184929

The virDomainGetMetadata function was designed to support also retrieval

of app specific metadata from the <metadata> element. This functionality

was never implemented originally.

(cherry picked from commit ac38bff077642daa17f9a82480062ebef4c11a7b)

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/conf/domain_conf.c   |  19 ++++----

 src/libvirt_private.syms |   1 +

 src/util/virxml.c        | 122 +++++++++++++++++++++++++++++++++++++++++++++++

 src/util/virxml.h        |   7 +++

 4 files changed, 140 insertions(+), 9 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c

index 6817e0e..c104218 100644

--- a/src/conf/domain_conf.c

+++ b/src/conf/domain_conf.c

@@ -18987,7 +18987,6 @@ virDomainObjGetMetadata(virDomainObjPtr vm,

                         unsigned int flags)

 {

     virDomainDefPtr def;

-    char *field = NULL;

     char *ret = NULL;

     virCheckFlags(VIR_DOMAIN_AFFECT_LIVE |

@@ -19002,17 +19001,21 @@ virDomainObjGetMetadata(virDomainObjPtr vm,

     switch ((virDomainMetadataType) type) {

     case VIR_DOMAIN_METADATA_DESCRIPTION:

-        field = def->description;

+        if (VIR_STRDUP(ret, def->description) < 0)

+            goto cleanup;

         break;

     case VIR_DOMAIN_METADATA_TITLE:

-        field = def->title;

+        if (VIR_STRDUP(ret, def->title) < 0)

+            goto cleanup;

         break;

     case VIR_DOMAIN_METADATA_ELEMENT:

-        virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",

-                       _("<metadata> element is not yet supported"));

-        goto cleanup;

+        if (!def->metadata)

+            break;

+

+        if (virXMLExtractNamespaceXML(def->metadata, uri, &ret) < 0)

+            goto cleanup;

         break;

     default:

@@ -19022,12 +19025,10 @@ virDomainObjGetMetadata(virDomainObjPtr vm,

         break;

     }

-    if (!field)

+    if (!ret)

         virReportError(VIR_ERR_NO_DOMAIN_METADATA, "%s",

                        _("Requested metadata element is not present"));

-    ignore_value(VIR_STRDUP(ret, field));

-

 cleanup:

     return ret;

 }

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index 3df4379..1fbee18 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -2140,6 +2140,7 @@ virUUIDParse;

 # util/virxml.h

 virXMLChildElementCount;

+virXMLExtractNamespaceXML;

 virXMLNodeToString;

 virXMLParseHelper;

 virXMLPickShellSafeComment;

diff --git a/src/util/virxml.c b/src/util/virxml.c

index 9bb8bf0..9048d78 100644

--- a/src/util/virxml.c

+++ b/src/util/virxml.c

@@ -928,3 +928,125 @@ cleanup:

      return ret;

 }

+

+typedef int (*virXMLForeachCallback)(xmlNodePtr node,

+                                     void *opaque);

+

+static int

+virXMLForeachNode(xmlNodePtr root,

+                  virXMLForeachCallback cb,

+                  void *opaque);

+

+static int

+virXMLForeachNode(xmlNodePtr root,

+                  virXMLForeachCallback cb,

+                  void *opaque)

+{

+    xmlNodePtr next;

+    int ret;

+

+    for (next = root; next; next = next->next) {

+        if ((ret = cb(next, opaque)) != 0)

+            return ret;

+

+        /* recurse into children */

+        if (next->children) {

+            if ((ret = virXMLForeachNode(next->children, cb, opaque)) != 0)

+                return ret;

+        }

+    }

+

+    return 0;

+}

+

+

+static int

+virXMLRemoveElementNamespace(xmlNodePtr node,

+                             void *opaque)

+{

+    const char *uri = opaque;

+

+    if (node->ns &&

+        STREQ_NULLABLE((const char *)node->ns->href, uri))

+        xmlSetNs(node, NULL);

+    return 0;

+}

+

+

+xmlNodePtr

+virXMLFindChildNodeByNs(xmlNodePtr root,

+                        const char *uri)

+{

+    xmlNodePtr next;

+

+    for (next = root->children; next; next = next->next) {

+        if (next->ns &&

+            STREQ_NULLABLE((const char *) next->ns->href, uri))

+            return next;

+    }

+

+    return NULL;

+}

+

+

+/**

+ * virXMLExtractNamespaceXML: extract a sub-namespace of XML as string

+ */

+int

+virXMLExtractNamespaceXML(xmlNodePtr root,

+                          const char *uri,

+                          char **doc)

+{

+    xmlNodePtr node;

+    xmlNodePtr nodeCopy = NULL;

+    xmlNsPtr actualNs;

+    xmlNsPtr prevNs = NULL;

+    char *xmlstr = NULL;

+    int ret = -1;

+

+    if (!(node = virXMLFindChildNodeByNs(root, uri))) {

+        /* node not found */

+        ret = 1;

+        goto cleanup;

+    }

+

+    /* copy the node so that we can modify the namespace */

+    if (!(nodeCopy = xmlCopyNode(node, 1))) {

+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",

+                       _("Failed to copy XML node"));

+        goto cleanup;

+    }

+

+    virXMLForeachNode(nodeCopy, virXMLRemoveElementNamespace,

+                      (void *)uri);

+

+    /* remove the namespace declaration

+     *  - it's only a single linked list ... doh */

+    for (actualNs = nodeCopy->nsDef; actualNs; actualNs = actualNs->next) {

+        if (STREQ_NULLABLE((const char *)actualNs->href, uri)) {

+

+            /* unlink */

+            if (prevNs)

+                prevNs->next = actualNs->next;

+            else

+                nodeCopy->nsDef = actualNs->next;

+

+            /* discard */

+            xmlFreeNs(actualNs);

+            break;

+        }

+

+        prevNs = actualNs;

+    }

+

+    if (!(xmlstr = virXMLNodeToString(nodeCopy->doc, nodeCopy)))

+        goto cleanup;

+

+    ret = 0;

+

+cleanup:

+    if (doc)

+        *doc = xmlstr;

+    xmlFreeNode(nodeCopy);

+    return ret;

+}

diff --git a/src/util/virxml.h b/src/util/virxml.h

index bb34069..7dc6c9d 100644

--- a/src/util/virxml.h

+++ b/src/util/virxml.h

@@ -165,4 +165,11 @@ int virXMLSaveFile(const char *path,

 char *virXMLNodeToString(xmlDocPtr doc, xmlNodePtr node);

+xmlNodePtr virXMLFindChildNodeByNs(xmlNodePtr root,

+                                   const char *uri);

+

+int virXMLExtractNamespaceXML(xmlNodePtr root,

+                              const char *uri,

+                              char **doc);

+

 #endif                          /* __VIR_XML_H__ */

-- 

2.2.1