Simplify str_to_multibyte and related code

* src/character.h (str_to_multibyte):
* src/character.c (str_to_multibyte): Remove `nbytes` argument; return
it instead.  Copy forwards.
* src/fns.c (concat_to_string, Fstring_make_multibyte):
Use str_to_multibyte.
(string_make_multibyte): Remove.
(string_to_multibyte):
* src/print.c (print_string):  Adapt calls.

1 files changed, 14 insertions, 36 deletions

diff --git a/src/fns.c b/src/fns.c
index 7d8f957ef98..eb83471649e 100644
--- a/src/fns.c
+++ b/src/fns.c
@@ -856,9 +856,8 @@ concat_to_string (ptrdiff_t nargs, Lisp_Object *args)
 	  else
 	    {
 	      /* Copy a single-byte string to a multibyte string.  */
-	      toindex_byte += copy_text (SDATA (arg),
-					 SDATA (result) + toindex_byte,
-					 nchars, 0, 1);
+	      toindex_byte += str_to_multibyte (SDATA (result) + toindex_byte,
+						SDATA (arg), nchars);
 	    }
 	  toindex += nchars;
 	}
@@ -1205,37 +1204,6 @@ string_byte_to_char (Lisp_Object string, ptrdiff_t byte_index)
   return i;
 }
 
-/* Convert STRING to a multibyte string.  */
-
-static Lisp_Object
-string_make_multibyte (Lisp_Object string)
-{
-  unsigned char *buf;
-  ptrdiff_t nbytes;
-  Lisp_Object ret;
-  USE_SAFE_ALLOCA;
-
-  if (STRING_MULTIBYTE (string))
-    return string;
-
-  nbytes = count_size_as_multibyte (SDATA (string),
-				    SCHARS (string));
-  /* If all the chars are ASCII, they won't need any more bytes
-     once converted.  In that case, we can return STRING itself.  */
-  if (nbytes == SBYTES (string))
-    return string;
-
-  buf = SAFE_ALLOCA (nbytes);
-  copy_text (SDATA (string), buf, SBYTES (string),
-	     0, 1);
-
-  ret = make_multibyte_string ((char *) buf, SCHARS (string), nbytes);
-  SAFE_FREE ();
-
-  return ret;
-}
-
-
 /* Convert STRING (if unibyte) to a multibyte string without changing
    the number of characters.  Characters 0x80..0xff are interpreted as
    raw bytes. */
@@ -1254,7 +1222,7 @@ string_to_multibyte (Lisp_Object string)
     return make_multibyte_string (SSDATA (string), nbytes, nbytes);
 
   Lisp_Object ret = make_uninit_multibyte_string (nchars, nbytes);
-  str_to_multibyte (SDATA (ret), SDATA (string), nchars, nbytes);
+  str_to_multibyte (SDATA (ret), SDATA (string), nchars);
   return ret;
 }
 
@@ -1299,7 +1267,17 @@ string the same way whether it is unibyte or multibyte.)  */)
 {
   CHECK_STRING (string);
 
-  return string_make_multibyte (string);
+  if (STRING_MULTIBYTE (string))
+    return string;
+
+  ptrdiff_t nchars = SCHARS (string);
+  ptrdiff_t nbytes = count_size_as_multibyte (SDATA (string), nchars);
+  if (nbytes == nchars)
+    return string;
+
+  Lisp_Object ret = make_uninit_multibyte_string (nchars, nbytes);
+  str_to_multibyte (SDATA (ret), SDATA (string), nchars);
+  return ret;
 }
 
 DEFUN ("string-make-unibyte", Fstring_make_unibyte, Sstring_make_unibyte,