[libxml2] Patch for xinclude of text using multibyte characters

[Daniel Veillard <veillard src gnome org>]

commit dce1c8baaeaa4f23874c59da91d9ecc0e31a787c
Author: Vitaly Ostanin <vitaly ostanin gmail com>
Date:   Fri Aug 17 20:42:52 2012 +0800

    Patch for xinclude of text using multibyte characters
    
    for bug https://bugzilla.gnome.org/show_bug.cgi?id=633166
    
    When you xinclude a text file, reading portions (by 4000 bytes) of the
    buffer incorrectly handled the situation when the end comes across
    portions of the bytes in a multibyte character.

 xinclude.c |   22 ++++++++++++++++------
 1 files changed, 16 insertions(+), 6 deletions(-)
---
diff --git a/xinclude.c b/xinclude.c
index a42793e..a836958 100644
--- a/xinclude.c
+++ b/xinclude.c
@@ -1801,6 +1801,7 @@ xmlXIncludeLoadTxt(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
     xmlCharEncoding enc = (xmlCharEncoding) 0;
     xmlParserCtxtPtr pctxt;
     xmlParserInputPtr inputStream;
+    int xinclude_multibyte_fallback_used = 0;
 
     /*
      * Check the URL and remove any fragment identifier
@@ -1897,6 +1898,7 @@ xmlXIncludeLoadTxt(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
     /*
      * Scan all chars from the resource and add the to the node
      */
+xinclude_multibyte_fallback:
     while (xmlParserInputBufferRead(buf, 128) > 0) {
 	int len;
 	const xmlChar *content;
@@ -1909,13 +1911,21 @@ xmlXIncludeLoadTxt(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
 
 	    cur = xmlStringCurrentChar(NULL, &content[i], &l);
 	    if (!IS_CHAR(cur)) {
-		xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
-		               XML_XINCLUDE_INVALID_CHAR,
-			       "%s contains invalid char\n", URL);
-		xmlFreeParserInputBuffer(buf);
-		xmlFree(URL);
-		return(-1);
+		/* Handle splitted multibyte char at buffer boundary */
+		if (((len - i) < 4) && (!xinclude_multibyte_fallback_used)) {
+		    xinclude_multibyte_fallback_used = 1;
+		    xmlBufShrink(buf->buffer, i);
+		    goto xinclude_multibyte_fallback;
+		} else {
+		    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
+				   XML_XINCLUDE_INVALID_CHAR,
+				   "%s contains invalid char\n", URL);
+		    xmlFreeParserInputBuffer(buf);
+		    xmlFree(URL);
+		    return(-1);
+		}
 	    } else {
+		xinclude_multibyte_fallback_used = 0;
 		xmlNodeAddContentLen(node, &content[i], l);
 	    }
 	    i += l;