[b2816a3afe] Fix counting of malformed sequences at end of string.

2 files changed, 13 insertions, 9 deletions

diff --git a/generic/tclUtf.c b/generic/tclUtf.c
index 4147bbc..80f3be8 100644
--- a/generic/tclUtf.c
+++ b/generic/tclUtf.c
@@ -548,17 +548,18 @@ Tcl_NumUtfChars(
 	    i++;
 	}
 	/* Loop over the remaining string where call must happen */
-	while ((src < endPtr) && Tcl_UtfCharComplete(src, endPtr - src)) {
-	    src += TclUtfToUniChar(src, &ch);
+	while (src < endPtr) {
+	    if (Tcl_UtfCharComplete(src, endPtr - src)) {
+		src += TclUtfToUniChar(src, &ch);
+	    } else {
+		/*
+		 * src points to incomplete UTF-8 sequence 
+		 * Treat first byte as character and count it
+		 */
+		src++;
+	    }
 	    i++;
 	}
-	if (src < endPtr) {
-	    /*
-	     * String ends in an incomplete UTF-8 sequence.
-	     * Count every byte in it.
-	     */
-	    i += endPtr - src;
-	}
     }
     return i;
 }
diff --git a/tests/utf.test b/tests/utf.test
index 8aa3757..f48299d 100644
--- a/tests/utf.test
+++ b/tests/utf.test
@@ -175,6 +175,9 @@ test utf-4.12.1 {Tcl_NumUtfChars: #4-byte UTF-8 character} {testnumutfchars test
 test utf-4.12.2 {Tcl_NumUtfChars: #4-byte UTF-8 character} {testnumutfchars testbytestring utf16} {
     testnumutfchars [testbytestring \xF0\x9F\x92\xA9] end
 } 2
+test utf-4.13 {Tcl_NumUtfChars: end of string} {testnumutfchars testbytestring} { 
+    testnumutfchars foobar[testbytestring \xF2\xC2\xA0] end
+} 8
 
 test utf-5.1 {Tcl_UtfFindFirst} {testfindfirst testbytestring} {
     testfindfirst [testbytestring abcbc] 98