Avoid calls to strlen in miscellaneous functions.

* buffer.c (init_buffer): Use precalculated len, adjust if needed.
* font.c (Ffont_xlfd_name): Likewise.  Change to call make_string.
* lread.c (openp): Likewise.

1 files changed, 12 insertions, 10 deletions

diff --git a/src/lread.c b/src/lread.c
index c69190c37b6..900a25372d8 100644
--- a/src/lread.c
+++ b/src/lread.c
@@ -1489,7 +1489,7 @@ openp (Lisp_Object path, Lisp_Object str, Lisp_Object suffixes, Lisp_Object *sto
       for (tail = NILP (suffixes) ? Fcons (empty_unibyte_string, Qnil) : suffixes;
            CONSP (tail); tail = XCDR (tail))
         {
-          ptrdiff_t lsuffix = SBYTES (XCAR (tail));
+          ptrdiff_t fnlen, lsuffix = SBYTES (XCAR (tail));
           Lisp_Object handler;
           int exists;
 
@@ -1499,20 +1499,22 @@ openp (Lisp_Object path, Lisp_Object str, Lisp_Object suffixes, Lisp_Object *sto
               && SREF (filename, 0) == '/'
               && SREF (filename, 1) == ':')
             {
-              strncpy (fn, SSDATA (filename) + 2,
-                       SBYTES (filename) - 2);
-              fn[SBYTES (filename) - 2] = 0;
+              fnlen = SBYTES (filename) - 2;
+              strncpy (fn, SSDATA (filename) + 2, fnlen);
+              fn[fnlen] = '\0';
             }
           else
             {
-              strncpy (fn, SSDATA (filename),
-                       SBYTES (filename));
-              fn[SBYTES (filename)] = 0;
+              fnlen = SBYTES (filename);
+              strncpy (fn, SSDATA (filename), fnlen);
+              fn[fnlen] = '\0';
             }
 
           if (lsuffix != 0)  /* Bug happens on CCI if lsuffix is 0.  */
-            strncat (fn, SSDATA (XCAR (tail)), lsuffix);
-
+            {
+              strncat (fn, SSDATA (XCAR (tail)), lsuffix);
+              fnlen += lsuffix;
+            }
           /* Check that the file exists and is not a directory.  */
           /* We used to only check for handlers on non-absolute file names:
                 if (absolute)
@@ -1521,7 +1523,7 @@ openp (Lisp_Object path, Lisp_Object str, Lisp_Object suffixes, Lisp_Object *sto
                   handler = Ffind_file_name_handler (filename, Qfile_exists_p);
              It's not clear why that was the case and it breaks things like
              (load "/bar.el") where the file is actually "/bar.el.gz".  */
-          string = build_string (fn);
+          string = make_string (fn, fnlen);
           handler = Ffind_file_name_handler (string, Qfile_exists_p);
           if ((!NILP (handler) || !NILP (predicate)) && !NATNUMP (predicate))
             {