1 files changed, 17 insertions, 5 deletions

diff --git a/xmlstring.c b/xmlstring.c
index af4e5c8..db94432 100644
--- a/xmlstring.c
+++ b/xmlstring.c
@@ -92,8 +92,10 @@ xmlCharStrndup(const char *cur, int len) {
         xmlErrMemory(NULL, NULL);
         return(NULL);
     }
-    for (i = 0;i < len;i++)
+    for (i = 0;i < len;i++) {
         ret[i] = (xmlChar) cur[i];
+        if (ret[i] == 0) return(ret);
+    }
     ret[len] = 0;
     return(ret);
 }
@@ -478,6 +480,8 @@ xmlStrncatNew(const xmlChar *str1, const xmlChar *str2, int len) {
     int size;
     xmlChar *ret;
 
+    if (len < 0)
+        len = xmlStrlen(str2);
     if ((str2 == NULL) || (len == 0))
         return(xmlStrdup(str1));
     if (str1 == NULL)
@@ -743,7 +747,8 @@ xmlGetUTF8Char(const unsigned char *utf, int *len) {
     return(c);
 
 error:
-    *len = 0;
+    if (len != NULL)
+	*len = 0;
     return(-1);
 }
 
@@ -766,6 +771,8 @@ xmlCheckUTF8(const unsigned char *utf)
     int ix;
     unsigned char c;
 
+    if (utf == NULL)
+        return(0);
     /*
      * utf is a string of 1, 2, 3 or 4 bytes.  The valid strings
      * are as follows (in "bit format"):
@@ -804,10 +811,10 @@ xmlCheckUTF8(const unsigned char *utf)
  * @len:  the number of characters in the array
  *
  * storage size of an UTF8 string
+ * the behaviour is not garanteed if the input string is not UTF-8
  *
  * Returns the storage size of
  * the first 'len' characters of ARRAY
- *
  */
 
 int
@@ -815,6 +822,9 @@ xmlUTF8Strsize(const xmlChar *utf, int len) {
     const xmlChar   *ptr=utf;
     xmlChar         ch;
 
+    if (utf == NULL)
+        return(0);
+
     if (len <= 0)
         return(0);
 
@@ -822,8 +832,10 @@ xmlUTF8Strsize(const xmlChar *utf, int len) {
         if ( !*ptr )
             break;
         if ( (ch = *ptr++) & 0x80)
-            while ( (ch<<=1) & 0x80 )
+            while ((ch<<=1) & 0x80 ) {
                 ptr++;
+		if (*ptr == 0) break;
+	    }
     }
     return (ptr - utf);
 }
@@ -867,7 +879,7 @@ xmlUTF8Strndup(const xmlChar *utf, int len) {
  *
  * Returns a pointer to the UTF8 character or NULL
  */
-xmlChar *
+const xmlChar *
 xmlUTF8Strpos(const xmlChar *utf, int pos) {
     xmlChar ch;