new module 'wctob'

[Bruno Haible]

The next module for ISO C 99 multibyte functions: wctob.

2008-12-18  Bruno Haible  <address@hidden>

        New module 'wctob'.
        * lib/wchar.in.h (wctob): New declaration.
        * lib/wctob.c: New file.
        * m4/wctob.m4: New file.
        * modules/wctob: New file.
        * m4/wchar.m4 (gl_WCHAR_H_DEFAULTS): Initialize GNULIB_WCTOB and
        HAVE_WCTOB.
        * modules/wchar (Makefile.am): Substitute GNULIB_WCTOB and HAVE_WCTOB.
        * doc/posix-functions/wctob.texi: Document the new module.

================================= lib/wctob.c =================================
/* Convert wide character to unibyte character.
   Copyright (C) 2008 Free Software Foundation, Inc.
   Written by Bruno Haible <address@hidden>, 2008.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <wchar.h>

#include <stdio.h>
#include <stdlib.h>

int
wctob (wint_t wc)
{
  char buf[64];

  if (!(MB_CUR_MAX <= sizeof (buf)))
    abort ();
  if (wctomb (buf, wc) == 1)
    return (unsigned char) buf[0];
  else
    return EOF;
}
================================= m4/wctob.m4 =================================
# wctob.m4 serial 1
dnl Copyright (C) 2008 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_WCTOB],
[
  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])

  AC_CHECK_FUNCS_ONCE([wctob])
  if test $ac_cv_func_wctob = no; then
    HAVE_WCTOB=0
    gl_REPLACE_WCHAR_H
    AC_LIBOBJ([wctob])
    gl_PREREQ_WCTOB
  fi
])

# Prerequisites of lib/wctob.c.
AC_DEFUN([gl_PREREQ_WCTOB], [
  :
])
================================ modules/wctob ================================
Description:
wctob() function: convert wide character to unibyte character.

Files:
lib/wctob.c
m4/wctob.m4

Depends-on:
wchar

configure.ac:
gl_FUNC_WCTOB
gl_WCHAR_MODULE_INDICATOR([wctob])

Makefile.am:

Include:
<wchar.h>

License:
LGPL

Maintainer:
Bruno Haible

===============================================================================
--- lib/wchar.in.h.orig 2008-12-19 03:06:19.000000000 +0100
+++ lib/wchar.in.h      2008-12-19 03:06:05.000000000 +0100
@@ -85,6 +85,20 @@
 #endif
 
 
+/* Convert a wide character to a single-byte character.  */
+#if @GNULIB_WCTOB@
+# if address@hidden@
+extern int wctob (wint_t wc);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef wctob
+# define wctob(w) \
+    (GL_LINK_WARNING ("wctob is unportable - " \
+                      "use gnulib module wctob for portability"), \
+     wctob (w))
+#endif
+
+
 /* Test whether *PS is in the initial state.  */
 #if @GNULIB_MBSINIT@
 # if address@hidden@
--- m4/wchar.m4.orig    2008-12-19 03:06:19.000000000 +0100
+++ m4/wchar.m4 2008-12-19 03:06:05.000000000 +0100
@@ -7,7 +7,7 @@
 
 dnl Written by Eric Blake.
 
-# wchar.m4 serial 8
+# wchar.m4 serial 9
 
 AC_DEFUN([gl_WCHAR_H],
 [
@@ -62,10 +62,12 @@
 AC_DEFUN([gl_WCHAR_H_DEFAULTS],
 [
   GNULIB_BTOWC=0;   AC_SUBST([GNULIB_BTOWC])
+  GNULIB_WCTOB=0;   AC_SUBST([GNULIB_WCTOB])
   GNULIB_MBSINIT=0; AC_SUBST([GNULIB_MBSINIT])
   GNULIB_WCWIDTH=0; AC_SUBST([GNULIB_WCWIDTH])
   dnl Assume proper GNU behavior unless another module says otherwise.
   HAVE_BTOWC=1;        AC_SUBST([HAVE_BTOWC])
+  HAVE_WCTOB=1;        AC_SUBST([HAVE_WCTOB])
   HAVE_MBSINIT=1;      AC_SUBST([HAVE_MBSINIT])
   HAVE_DECL_WCWIDTH=1; AC_SUBST([HAVE_DECL_WCWIDTH])
   REPLACE_WCWIDTH=0;   AC_SUBST([REPLACE_WCWIDTH])
--- modules/wchar.orig  2008-12-19 03:06:19.000000000 +0100
+++ modules/wchar       2008-12-19 03:06:05.000000000 +0100
@@ -24,12 +24,14 @@
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
              -e 's|@''PRAGMA_SYSTEM_HEADER''@|@PRAGMA_SYSTEM_HEADER@|g' \
              -e 's|@''NEXT_WCHAR_H''@|$(NEXT_WCHAR_H)|g' \
-             -e 's/@''HAVE_WCHAR_H''@/$(HAVE_WCHAR_H)/g' \
+             -e 's|@''HAVE_WCHAR_H''@|$(HAVE_WCHAR_H)|g' \
              -e 's|@''GNULIB_BTOWC''@|$(GNULIB_BTOWC)|g' \
+             -e 's|@''GNULIB_WCTOB''@|$(GNULIB_WCTOB)|g' \
              -e 's|@''GNULIB_MBSINIT''@|$(GNULIB_MBSINIT)|g' \
              -e 's|@''GNULIB_WCWIDTH''@|$(GNULIB_WCWIDTH)|g' \
-             -e 's/@''HAVE_WINT_T''@/$(HAVE_WINT_T)/g' \
+             -e 's|@''HAVE_WINT_T''@|$(HAVE_WINT_T)|g' \
              -e 's|@''HAVE_BTOWC''@|$(HAVE_BTOWC)|g' \
+             -e 's|@''HAVE_WCTOB''@|$(HAVE_WCTOB)|g' \
              -e 's|@''HAVE_MBSINIT''@|$(HAVE_MBSINIT)|g' \
              -e 's|@''HAVE_DECL_WCWIDTH''@|$(HAVE_DECL_WCWIDTH)|g' \
              -e 's|@''REPLACE_WCWIDTH''@|$(REPLACE_WCWIDTH)|g' \
--- doc/posix-functions/wctob.texi.orig 2008-12-19 03:06:19.000000000 +0100
+++ doc/posix-functions/wctob.texi      2008-12-19 03:06:05.000000000 +0100
@@ -4,18 +4,18 @@
 
 POSIX specification: 
@url{http://www.opengroup.org/onlinepubs/9699919799/functions/wctob.html}
 
-Gnulib module: ---
+Gnulib module: wctob
 
 Portability problems fixed by Gnulib:
 @itemize
address@hidden
+This function is missing on some platforms:
+HP-UX 11, IRIX 5.3, Solaris 2.6, mingw, Interix 3.5.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
 @item
-This function is missing on some platforms:
-HP-UX 11, IRIX 5.3, Solaris 2.6, mingw, Interix 3.5.
address@hidden
 On Windows platforms, @code{wchar_t} is a 16-bit type and therefore cannot
 accommodate all Unicode characters.
 @end itemize