[libvirt PATCH v6 5/8] virxml: Add virXMLPropEnum

[Tim Wiederhake]

Convenience function to return the value of an enum XML attribute.

Signed-off-by: Tim Wiederhake <twiederh at redhat.com>
Reviewed-by: Peter Krempa <pkrempa at redhat.com>
---
 src/libvirt_private.syms |  1 +
 src/util/virxml.c        | 48 ++++++++++++++++++++++++++++++++++++++++
 src/util/virxml.h        |  8 +++++++
 3 files changed, 57 insertions(+)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 9c94edb523..0fcbf546a6 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -3548,6 +3548,7 @@ virXMLNodeSanitizeNamespaces;
 virXMLNodeToString;
 virXMLParseHelper;
 virXMLPickShellSafeComment;
+virXMLPropEnum;
 virXMLPropInt;
 virXMLPropString;
 virXMLPropStringLimit;
diff --git a/src/util/virxml.c b/src/util/virxml.c
index 662a700262..94948ca021 100644
--- a/src/util/virxml.c
+++ b/src/util/virxml.c
@@ -759,6 +759,54 @@ virXMLPropUInt(xmlNodePtr node,
 }
 
 
+/**
+ * virXMLPropEnum:
+ * @node: XML dom node pointer
+ * @name: Name of the property (attribute) to get
+ * @strToInt: Conversion function to turn enum name to value. Expected to
+ *            return negative value on failure.
+ * @flags: Bitwise or of virXMLPropFlags
+ * @result: The returned value
+ *
+ * Convenience function to return value of an enum attribute.
+ *
+ * Returns 1 in case of success in which case @result is set,
+ *         or 0 if the attribute is not present,
+ *         or -1 and reports an error on failure.
+ */
+int
+virXMLPropEnum(xmlNodePtr node,
+               const char* name,
+               int (*strToInt)(const char*),
+               virXMLPropFlags flags,
+               unsigned int *result)
+{
+    g_autofree char *tmp = NULL;
+    int ret;
+
+    if (!(tmp = virXMLPropString(node, name))) {
+        if (!(flags & VIR_XML_PROP_REQUIRED))
+            return 0;
+
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Missing required attribute '%s' in element '%s'"),
+                       name, node->name);
+        return -1;
+    }
+
+    ret = strToInt(tmp);
+    if (ret < 0 ||
+        ((flags & VIR_XML_PROP_NONZERO) && (ret == 0))) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Invalid value for attribute '%s' in element '%s': '%s'."),
+                       name, node->name, NULLSTR(tmp));
+        return -1;
+    }
+
+    *result = ret;
+    return 0;
+}
+
 /**
  * virXPathBoolean:
  * @xpath: the XPath string to evaluate
diff --git a/src/util/virxml.h b/src/util/virxml.h
index aed4715123..d362cfb794 100644
--- a/src/util/virxml.h
+++ b/src/util/virxml.h
@@ -112,6 +112,14 @@ int virXMLPropUInt(xmlNodePtr node,
                    unsigned int *result)
     ATTRIBUTE_NONNULL(0) ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(4);
 
+int virXMLPropEnum(xmlNodePtr node,
+                   const char* name,
+                   int (*strToInt)(const char*),
+                   virXMLPropFlags flags,
+                   unsigned int *result)
+    ATTRIBUTE_NONNULL(0) ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2)
+    ATTRIBUTE_NONNULL(4);
+
 /* Internal function; prefer the macros below.  */
 xmlDocPtr      virXMLParseHelper(int domcode,
                                  const char *filename,
-- 
2.26.2