* font.c (Ffont_get_glyphs): Use validate_subarray and fix

the case where an optional string is used.  Adjust docstring.

2 files changed, 35 insertions, 24 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index c03b6dad06f..b57c76d5e3f 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2014-10-07  Dmitry Antipov  <dmantipov@yandex.ru>
+
+        * font.c (Ffont_get_glyphs): Use validate_subarray and fix
+        the case where an optional string is used.  Adjust docstring.
+
 2014-10-06  Stefan Monnier  <monnier@iro.umontreal.ca>
 
         * lisp.mk (lisp): Remove w32-common-fns.elc.
diff --git a/src/font.c b/src/font.c
index 8405065a0d0..d73aed76d40 100644
--- a/src/font.c
+++ b/src/font.c
@@ -4687,9 +4687,10 @@ DEFUN ("font-get-glyphs", Ffont_get_glyphs, Sfont_get_glyphs, 3, 4, 0,
        doc:
        /* Return a vector of FONT-OBJECT's glyphs for the specified characters.
 FROM and TO are positions (integers or markers) specifying a region
-of the current buffer.
-If the optional fourth arg OBJECT is not nil, it is a string or a
-vector containing the target characters.
+of the current buffer, and can be in either order.  If the optional
+fourth arg OBJECT is not nil, it is a string or a vector containing
+the target characters between indices FROM and TO, which are treated
+as in `substring'.
 
 Each element is a vector containing information of a glyph in this format:
   [FROM-IDX TO-IDX C CODE WIDTH LBEARING RBEARING ASCENT DESCENT ADJUSTMENT]
@@ -4732,45 +4733,50 @@ the corresponding element is nil.  */)
   else if (STRINGP (object))
     {
       const unsigned char *p;
+      ptrdiff_t ifrom, ito;
 
-      CHECK_NUMBER (from);
-      CHECK_NUMBER (to);
-      if (XINT (from) < 0 || XINT (from) > XINT (to)
-          || XINT (to) > SCHARS (object))
-        args_out_of_range_3 (object, from, to);
-      if (EQ (from, to))
+      validate_subarray (object, from, to, SCHARS (object), &ifrom, &ito);
+      if (ifrom == ito)
         return Qnil;
-      len = XFASTINT (to) - XFASTINT (from);
+      len = ito - ifrom;
       SAFE_ALLOCA_LISP (chars, len);
       p = SDATA (object);
       if (STRING_MULTIBYTE (object))
-        for (i = 0; i < len; i++)
+        {
+          int c;
+
+          /* Skip IFROM characters from the beginning.  */
+          for (i = 0; i < ifrom; i++)
+            c = STRING_CHAR_ADVANCE (p);
+
+          /* Now fetch an interesting characters.  */
+          for (i = 0; i < len; i++)
           {
-            int c = STRING_CHAR_ADVANCE (p);
+            c = STRING_CHAR_ADVANCE (p);
             chars[i] = make_number (c);
           }
+        }
       else
         for (i = 0; i < len; i++)
-          chars[i] = make_number (p[i]);
+          chars[i] = make_number (p[ifrom + i]);
     }
-  else
+  else if (VECTORP (object))
     {
-      CHECK_VECTOR (object);
-      CHECK_NUMBER (from);
-      CHECK_NUMBER (to);
-      if (XINT (from) < 0 || XINT (from) > XINT (to)
-          || XINT (to) > ASIZE (object))
-        args_out_of_range_3 (object, from, to);
-      if (EQ (from, to))
+      ptrdiff_t ifrom, ito;
+
+      validate_subarray (object, from, to, ASIZE (object), &ifrom, &ito);
+      if (ifrom == ito)
         return Qnil;
-      len = XFASTINT (to) - XFASTINT (from);
+      len = ito - ifrom;
       for (i = 0; i < len; i++)
         {
-          Lisp_Object elt = AREF (object, XFASTINT (from) + i);
+          Lisp_Object elt = AREF (object, ifrom + i);
           CHECK_CHARACTER (elt);
         }
-      chars = aref_addr (object, XFASTINT (from));
+      chars = aref_addr (object, ifrom);
     }
+  else
+    wrong_type_argument (Qarrayp, object);
 
   vec = make_uninit_vector (len);
   for (i = 0; i < len; i++)