[libxslt] Fix regression in xsltComputeSortResult

[Nick Wellnhofer <nwellnhof src gnome org>]

commit b9044eaf3a94d33e9087b79f12efb6fe518e8216
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Wed Jun 16 16:59:43 2021 +0200

    Fix regression in xsltComputeSortResult
    
    After implementing locale support, xsltComputeSortResult returned
    strings transformed with strxfrm. This confused external users of this
    function, mainly WebKit derived browsers implementing their own sort
    function, similar to examples/xsltICUSort.c.
    
    Revert to the old behavior for external callers.

 libxslt/xsltutils.c | 34 +++++++++++++++++++++++++++-------
 1 file changed, 27 insertions(+), 7 deletions(-)
---
diff --git a/libxslt/xsltutils.c b/libxslt/xsltutils.c
index bc52c761..fdf7dec2 100644
--- a/libxslt/xsltutils.c
+++ b/libxslt/xsltutils.c
@@ -948,17 +948,19 @@ xsltDocumentSortFunction(xmlNodeSetPtr list) {
 }
 
 /**
- * xsltComputeSortResult:
+ * xsltComputeSortResultiInternal:
  * @ctxt:  a XSLT process context
  * @sort:  node list
+ * @xfrm:  Transform strings according to locale
  *
  * reorder the current node list accordingly to the set of sorting
  * requirement provided by the array of nodes.
  *
  * Returns a ordered XPath nodeset or NULL in case of error.
  */
-xmlXPathObjectPtr *
-xsltComputeSortResult(xsltTransformContextPtr ctxt, xmlNodePtr sort) {
+static xmlXPathObjectPtr *
+xsltComputeSortResultInternal(xsltTransformContextPtr ctxt, xmlNodePtr sort,
+                              int xfrm) {
 #ifdef XSLT_REFACTORED
     xsltStyleItemSortPtr comp;
 #else
@@ -1045,7 +1047,7 @@ xsltComputeSortResult(xsltTransformContextPtr ctxt, xmlNodePtr sort) {
                }
            } else {
                if (res->type == XPATH_STRING) {
-                   if (comp->locale != (xsltLocale)0) {
+                   if ((xfrm) && (comp->locale != (xsltLocale)0)) {
                        xmlChar *str = res->stringval;
                        res->stringval = (xmlChar *) xsltStrxfrm(comp->locale, str);
                        xmlFree(str);
@@ -1075,6 +1077,21 @@ xsltComputeSortResult(xsltTransformContextPtr ctxt, xmlNodePtr sort) {
     return(results);
 }
 
+/**
+ * xsltComputeSortResult:
+ * @ctxt:  a XSLT process context
+ * @sort:  node list
+ *
+ * reorder the current node list accordingly to the set of sorting
+ * requirement provided by the array of nodes.
+ *
+ * Returns a ordered XPath nodeset or NULL in case of error.
+ */
+xmlXPathObjectPtr *
+xsltComputeSortResult(xsltTransformContextPtr ctxt, xmlNodePtr sort) {
+    return xsltComputeSortResultInternal(ctxt, sort, /* xfrm */ 0);
+}
+
 /**
  * xsltDefaultSortFunction:
  * @ctxt:  a XSLT process context
@@ -1175,7 +1192,8 @@ xsltDefaultSortFunction(xsltTransformContextPtr ctxt, xmlNodePtr *sorts,
 
     len = list->nodeNr;
 
-    resultsTab[0] = xsltComputeSortResult(ctxt, sorts[0]);
+    resultsTab[0] = xsltComputeSortResultInternal(ctxt, sorts[0],
+                                                  /* xfrm */ 1);
     for (i = 1;i < XSLT_MAX_SORT;i++)
        resultsTab[i] = NULL;
 
@@ -1246,8 +1264,10 @@ xsltDefaultSortFunction(xsltTransformContextPtr ctxt, xmlNodePtr *sorts,
                         * full set, this might be optimized ... or not
                         */
                        if (resultsTab[depth] == NULL)
-                           resultsTab[depth] = xsltComputeSortResult(ctxt,
-                                                       sorts[depth]);
+                           resultsTab[depth] =
+                                xsltComputeSortResultInternal(ctxt,
+                                                              sorts[depth],
+                                                              /* xfrm */ 1);
                        res = resultsTab[depth];
                        if (res == NULL)
                            break;