(strwidth): Make it work for invalid bytes sequence.

(Fstring_width): Give byte length of STR to strwidth.

1 files changed, 6 insertions, 7 deletions

diff --git a/src/charset.c b/src/charset.c
index 6134f040663..7e9d1eab821 100644
--- a/src/charset.c
+++ b/src/charset.c
@@ -997,8 +997,8 @@ strwidth (str, len)
       else
         {
           Lisp_Object disp;
-          int thiswidth;
-          int c = STRING_CHAR (str, endp - str);
+          int thislen;
+          int c = STRING_CHAR_AND_LENGTH (str, endp - str, thislen);
 
           /* Get the way the display table would display it.  */
           if (dp)
@@ -1007,12 +1007,11 @@ strwidth (str, len)
             disp = Qnil;
 
           if (VECTORP (disp))
-            thiswidth = XVECTOR (disp)->size;
+            width += XVECTOR (disp)->size;
           else
-            thiswidth = ONE_BYTE_CHAR_WIDTH (*str);
+            width += ONE_BYTE_CHAR_WIDTH (*str);
 
-          width += thiswidth;
-          str += BYTES_BY_CHAR_HEAD (*str);
+          str += thislen;
         }
     }
   return width;
@@ -1030,7 +1029,7 @@ the following bytes is not checked.")
   Lisp_Object val;
 
   CHECK_STRING (str, 0);
-  XSETFASTINT (val, strwidth (XSTRING (str)->data, XSTRING (str)->size));
+  XSETFASTINT (val, strwidth (XSTRING (str)->data, XSTRING (str)->size_byte));
   return val;
 }