[libxml2] xmlNodeSetName: Allow setting the name to a substring of the currently set name

[Daniel Veillard <veillard src gnome org>]

commit f0dd6e11aa56addced3de33fab30529a51efaed5
Author: Tristan Van Berkom <tristan upstairslabs com>
Date:   Tue Apr 22 21:15:05 2014 -0400

    xmlNodeSetName: Allow setting the name to a substring of the currently set name
    
    Avoid freeing the currently set name until after having assigned the new name,
    this allows one to call xmlNodeSetName (node, node->name + 1) to set the new
    name of the node to a substring of the current name without introducing any
    crash and without requiring an extra strdup().

 tree.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/tree.c b/tree.c
index df6206d..7853e35 100644
--- a/tree.c
+++ b/tree.c
@@ -5096,6 +5096,7 @@ void
 xmlNodeSetName(xmlNodePtr cur, const xmlChar *name) {
     xmlDocPtr doc;
     xmlDictPtr dict;
+    const xmlChar *freeme = NULL;
 
     if (cur == NULL) return;
     if (name == NULL) return;
@@ -5133,12 +5134,16 @@ xmlNodeSetName(xmlNodePtr cur, const xmlChar *name) {
         dict = NULL;
     if (dict != NULL) {
         if ((cur->name != NULL) && (!xmlDictOwns(dict, cur->name)))
-           xmlFree((xmlChar *) cur->name);
+           freeme = cur->name;
        cur->name = xmlDictLookup(dict, name, -1);
     } else {
-       if (cur->name != NULL) xmlFree((xmlChar *) cur->name);
+       if (cur->name != NULL)
+           freeme = cur->name;
        cur->name = xmlStrdup(name);
     }
+
+    if (freeme)
+        xmlFree((xmlChar *) freeme);
 }
 #endif