Merge from trunk.

1 files changed, 40 insertions, 39 deletions

diff --git a/src/character.c b/src/character.c
index f15a20f6999..b85cedad937 100644
--- a/src/character.c
+++ b/src/character.c
@@ -308,6 +308,36 @@ If the multibyte character does not represent a byte, return -1.  */)
     }
 }
 
+
+/* Return width (columns) of C considering the buffer display table DP. */
+
+static ptrdiff_t
+char_width (int c, struct Lisp_Char_Table *dp)
+{
+  ptrdiff_t width = CHAR_WIDTH (c);
+
+  if (dp)
+    {
+      Lisp_Object disp = DISP_CHAR_VECTOR (dp, c), ch;
+      int i;
+
+      if (VECTORP (disp))
+        for (i = 0, width = 0; i < ASIZE (disp); i++)
+          {
+            ch = AREF (disp, i);
+            if (CHARACTERP (ch))
+              {
+                int w = CHAR_WIDTH (XFASTINT (ch));
+                if (INT_ADD_OVERFLOW (width, w))
+                  string_overflow ();
+                width += w;
+              }
+          }
+    }
+  return width;
+}
+
+
 DEFUN ("char-width", Fchar_width, Schar_width, 1, 1, 0,
        doc: /* Return width of CHAR when displayed in the current buffer.
 The width is measured by how many columns it occupies on the screen.
@@ -315,21 +345,12 @@ Tab is taken to occupy `tab-width' columns.
 usage: (char-width CHAR)  */)
   (Lisp_Object ch)
 {
-  Lisp_Object disp;
-  int c, width;
-  struct Lisp_Char_Table *dp = buffer_display_table ();
+  int c;
+  ptrdiff_t width;
 
   CHECK_CHARACTER (ch);
   c = XINT (ch);
-
-  /* Get the way the display table would display it.  */
-  disp = dp ? DISP_CHAR_VECTOR (dp, c) : Qnil;
-
-  if (VECTORP (disp))
-    width = sanitize_char_width (ASIZE (disp));
-  else
-    width = CHAR_WIDTH (c);
-
+  width = char_width (c, buffer_display_table ());
   return make_number (width);
 }
 
@@ -350,25 +371,16 @@ c_string_width (const unsigned char *str, ptrdiff_t len, int precision,
 
   while (i_byte < len)
     {
-      int bytes, thiswidth;
-      Lisp_Object val;
+      int bytes;
       int c = STRING_CHAR_AND_LENGTH (str + i_byte, bytes);
+      ptrdiff_t thiswidth = char_width (c, dp);
 
-      if (dp)
-        {
-          val = DISP_CHAR_VECTOR (dp, c);
-          if (VECTORP (val))
-            thiswidth = sanitize_char_width (ASIZE (val));
-          else
-            thiswidth = CHAR_WIDTH (c);
-        }
-      else
+      if (precision <= 0)
         {
-          thiswidth = CHAR_WIDTH (c);
+          if (INT_ADD_OVERFLOW (width, thiswidth))
+            string_overflow ();
         }
-
-      if (precision > 0
-          && (width + thiswidth > precision))
+      else if (precision - width < thiswidth)
         {
           *nchars = i;
           *nbytes = i_byte;
@@ -447,18 +459,7 @@ lisp_string_width (Lisp_Object string, ptrdiff_t precision,
           else
             c = str[i_byte], bytes = 1;
           chars = 1;
-          if (dp)
-            {
-              val = DISP_CHAR_VECTOR (dp, c);
-              if (VECTORP (val))
-                thiswidth = sanitize_char_width (ASIZE (val));
-              else
-                thiswidth = CHAR_WIDTH (c);
-            }
-          else
-            {
-              thiswidth = CHAR_WIDTH (c);
-            }
+          thiswidth = char_width (c, dp);
         }
 
       if (precision <= 0)