util: xml: Introduce virXMLPropLongLong

Add a helper for parsing long long values from XML properties with
semantics like virXMLPropInt.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/libvirt_private.syms

@@ -3682,6 +3682,7 @@ virXMLPickShellSafeComment;
 virXMLPropEnum;
 virXMLPropEnumDefault;
 virXMLPropInt;
+virXMLPropLongLong;
 virXMLPropString;
 virXMLPropStringRequired;
 virXMLPropTristateBool;

src/util/virxml.c

@@ -750,6 +750,70 @@ virXMLPropUInt(xmlNodePtr node,
 }
 
 
+/**
+ * virXMLPropLongLong:
+ * @node: XML dom node pointer
+ * @name: Name of the property (attribute) to get
+ * @base: Number base, see strtol
+ * @flags: Bitwise-OR of virXMLPropFlags
+ * @result: The returned value
+ * @defaultResult: Default value of @result in case the property is not found
+ *
+ * Convenience function to return value of a long long 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
+virXMLPropLongLong(xmlNodePtr node,
+                   const char *name,
+                   int base,
+                   virXMLPropFlags flags,
+                   long long *result,
+                   long long defaultResult)
+{
+    g_autofree char *tmp = NULL;
+    long long val;
+
+    *result = defaultResult;
+
+    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;
+    }
+
+    if (virStrToLong_ll(tmp, NULL, base, &val) < 0) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Invalid value for attribute '%s' in element '%s': '%s'. Expected long long integer value"),
+                       name, node->name, tmp);
+        return -1;
+    }
+
+    if ((flags & VIR_XML_PROP_NONNEGATIVE) && (val < 0)) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Invalid value for attribute '%s' in element '%s': '%s'. Expected non-negative value"),
+                       name, node->name, tmp);
+        return -1;
+    }
+
+    if ((flags & VIR_XML_PROP_NONZERO) && (val == 0)) {
+        virReportError(VIR_ERR_XML_ERROR,
+                       _("Invalid value for attribute '%s' in element '%s': Zero is not permitted"),
+                       name, node->name);
+        return -1;
+    }
+
+    *result = val;
+    return 1;
+}
+
+
 /**
  * virXMLPropULongLong:
  * @node: XML dom node pointer

src/util/virxml.h

@@ -141,6 +141,15 @@ virXMLPropUInt(xmlNodePtr node,
                unsigned int *result)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(5);
 
+int
+virXMLPropLongLong(xmlNodePtr node,
+                   const char *name,
+                   int base,
+                   virXMLPropFlags flags,
+                   long long *result,
+                   long long defaultResult)
+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(5);
+
 int
 virXMLPropULongLong(xmlNodePtr node,
                     const char* name,