Here's the replacement for a missing mbsrtowcs function.
Quite straightforward, except for a small hole in the specification:
ISO C 99 does not specify how the state is to be updated. glibc updates it
if and only if the dest argument is not NULL; this is what makes most sense.
2008-12-19 Bruno Haible <br...@clisp.org>
New module 'mbsrtowcs'.
* lib/wchar.in.h (mbsrtowcs): New declaration.
* lib/mbsrtowcs.c: New file.
* m4/mbsrtowcs.m4: New file.
* modules/mbsrtowcs: New file.
* m4/wchar.m4 (gl_WCHAR_H_DEFAULTS): Initialize GNULIB_MBSRTOWCS and
HAVE_MBSRTOWCS.
* modules/wchar (Makefile.am): Substitute GNULIB_MBSRTOWCS and
HAVE_MBSRTOWCS.
* doc/posix-functions/mbsrtowcs.texi: Document the new module.
=============================== lib/mbsrtowcs.c ===============================
/* Convert string to wide string.
Copyright (C) 2008 Free Software Foundation, Inc.
Written by Bruno Haible <br...@clisp.org>, 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 <errno.h>
#include <limits.h>
#include <stdlib.h>
#include "strnlen1.h"
static mbstate_t internal_state;
size_t
mbsrtowcs (wchar_t *dest, const char **srcp, size_t len, mbstate_t *ps)
{
if (ps == NULL)
ps = &internal_state;
{
const char *src = *srcp;
if (dest != NULL)
{
wchar_t *destptr = dest;
for (; len > 0; destptr++, len--)
{
size_t src_avail;
size_t ret;
/* An optimized variant of
src_avail = strnlen1 (src, MB_LEN_MAX); */
if (src[0] == '\0')
src_avail = 1;
else if (src[1] == '\0')
src_avail = 2;
else if (src[2] == '\0')
src_avail = 3;
else if (MB_LEN_MAX <= 4 || src[3] == '\0')
src_avail = 4;
else
src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4);
/* Parse the next multibyte character. */
ret = mbrtowc (destptr, src, src_avail, ps);
if (ret == (size_t)(-2))
/* Encountered a multibyte character that extends past a '\0' byte
or that is longer than MB_LEN_MAX bytes. Cannot happen. */
abort ();
if (ret == (size_t)(-1))
goto bad_input;
if (ret == 0)
{
src = NULL;
/* Here mbsinit (ps). */
break;
}
src += ret;
}
*srcp = src;
return destptr - dest;
}
else
{
/* Ignore dest and len, don't store *srcp at the end, and
don't clobber *ps. */
mbstate_t state = *ps;
size_t totalcount = 0;
for (;; totalcount++)
{
size_t src_avail;
size_t ret;
/* An optimized variant of
src_avail = strnlen1 (src, MB_LEN_MAX); */
if (src[0] == '\0')
src_avail = 1;
else if (src[1] == '\0')
src_avail = 2;
else if (src[2] == '\0')
src_avail = 3;
else if (MB_LEN_MAX <= 4 || src[3] == '\0')
src_avail = 4;
else
src_avail = 4 + strnlen1 (src + 4, MB_LEN_MAX - 4);
/* Parse the next multibyte character. */
ret = mbrtowc (NULL, src, src_avail, &state);
if (ret == (size_t)(-2))
/* Encountered a multibyte character that extends past a '\0' byte
or that is longer than MB_LEN_MAX bytes. Cannot happen. */
abort ();
if (ret == (size_t)(-1))
goto bad_input2;
if (ret == 0)
{
/* Here mbsinit (&state). */
break;
}
src += ret;
}
return totalcount;
}
bad_input:
*srcp = src;
bad_input2:
errno = EILSEQ;
return (size_t)(-1);
}
}
=============================== m4/mbsrtowcs.m4 ===============================
# mbsrtowcs.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_MBSRTOWCS],
[
AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
AC_REQUIRE([AC_TYPE_MBSTATE_T])
AC_CHECK_FUNCS_ONCE([mbsrtowcs])
if test $ac_cv_func_mbsrtowcs = no; then
HAVE_MBSRTOWCS=0
gl_REPLACE_WCHAR_H
AC_LIBOBJ([mbsrtowcs])
gl_PREREQ_MBSRTOWCS
fi
])
# Prerequisites of lib/mbsrtowcs.c.
AC_DEFUN([gl_PREREQ_MBSRTOWCS], [
:
])
============================== modules/mbsrtowcs ==============================
Description:
mbsrtowcs() function: convert string to wide string.
Files:
lib/mbsrtowcs.c
m4/mbsrtowcs.m4
m4/mbstate_t.m4
Depends-on:
wchar
mbrtowc
strnlen1
configure.ac:
gl_FUNC_MBSRTOWCS
gl_WCHAR_MODULE_INDICATOR([mbsrtowcs])
Makefile.am:
Include:
<wchar.h>
License:
LGPL
Maintainer:
Bruno Haible
===============================================================================
--- lib/wchar.in.h.orig 2008-12-20 01:55:20.000000000 +0100
+++ lib/wchar.in.h 2008-12-19 23:48:14.000000000 +0100
@@ -151,6 +151,20 @@
#endif
+/* Convert a string to a wide string. */
+#if @GNULIB_MBSRTOWCS@
+# if !...@have_mbsrtowcs@
+extern size_t mbsrtowcs (wchar_t *dest, const char **srcp, size_t len,
mbstate_t *ps);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef mbsrtowcs
+# define mbsrtowcs(d,s,l,p) \
+ (GL_LINK_WARNING ("mbsrtowcs is unportable - " \
+ "use gnulib module mbsrtowcs for portability"), \
+ mbsrtowcs (d, s, l, p))
+#endif
+
+
/* Return the number of screen columns needed for WC. */
#if @GNULIB_WCWIDTH@
# if @REPLACE_WCWIDTH@
--- m4/wchar.m4.orig 2008-12-20 01:55:20.000000000 +0100
+++ m4/wchar.m4 2008-12-19 23:50:50.000000000 +0100
@@ -7,7 +7,7 @@
dnl Written by Eric Blake.
-# wchar.m4 serial 10
+# wchar.m4 serial 11
AC_DEFUN([gl_WCHAR_H],
[
@@ -61,18 +61,20 @@
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_MBRTOWC=0; AC_SUBST([GNULIB_MBRTOWC])
- GNULIB_MBRLEN=0; AC_SUBST([GNULIB_MBRLEN])
- GNULIB_WCWIDTH=0; AC_SUBST([GNULIB_WCWIDTH])
+ GNULIB_BTOWC=0; AC_SUBST([GNULIB_BTOWC])
+ GNULIB_WCTOB=0; AC_SUBST([GNULIB_WCTOB])
+ GNULIB_MBSINIT=0; AC_SUBST([GNULIB_MBSINIT])
+ GNULIB_MBRTOWC=0; AC_SUBST([GNULIB_MBRTOWC])
+ GNULIB_MBRLEN=0; AC_SUBST([GNULIB_MBRLEN])
+ GNULIB_MBSRTOWCS=0; AC_SUBST([GNULIB_MBSRTOWCS])
+ 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_MBRTOWC=1; AC_SUBST([HAVE_MBRTOWC])
HAVE_MBRLEN=1; AC_SUBST([HAVE_MBRLEN])
+ HAVE_MBSRTOWCS=1; AC_SUBST([HAVE_MBSRTOWCS])
HAVE_DECL_WCWIDTH=1; AC_SUBST([HAVE_DECL_WCWIDTH])
REPLACE_WCWIDTH=0; AC_SUBST([REPLACE_WCWIDTH])
WCHAR_H=''; AC_SUBST([WCHAR_H])
--- modules/wchar.orig 2008-12-20 01:55:20.000000000 +0100
+++ modules/wchar 2008-12-19 23:49:38.000000000 +0100
@@ -30,6 +30,7 @@
-e 's|@''GNULIB_MBSINIT''@|$(GNULIB_MBSINIT)|g' \
-e 's|@''GNULIB_MBRTOWC''@|$(GNULIB_MBRTOWC)|g' \
-e 's|@''GNULIB_MBRLEN''@|$(GNULIB_MBRLEN)|g' \
+ -e 's|@''GNULIB_MBSRTOWCS''@|$(GNULIB_MBSRTOWCS)|g' \
-e 's|@''GNULIB_WCWIDTH''@|$(GNULIB_WCWIDTH)|g' \
-e 's|@''HAVE_WINT_T''@|$(HAVE_WINT_T)|g' \
-e 's|@''HAVE_BTOWC''@|$(HAVE_BTOWC)|g' \
@@ -37,6 +38,7 @@
-e 's|@''HAVE_MBSINIT''@|$(HAVE_MBSINIT)|g' \
-e 's|@''HAVE_MBRTOWC''@|$(HAVE_MBRTOWC)|g' \
-e 's|@''HAVE_MBRLEN''@|$(HAVE_MBRLEN)|g' \
+ -e 's|@''HAVE_MBSRTOWCS''@|$(HAVE_MBSRTOWCS)|g' \
-e 's|@''HAVE_DECL_WCWIDTH''@|$(HAVE_DECL_WCWIDTH)|g' \
-e 's|@''REPLACE_WCWIDTH''@|$(REPLACE_WCWIDTH)|g' \
-e '/definition of GL_LINK_WARNING/r $(LINK_WARNING_H)' \
--- doc/posix-functions/mbsrtowcs.texi.orig 2008-12-20 01:55:20.000000000
+0100
+++ doc/posix-functions/mbsrtowcs.texi 2008-12-19 23:55:41.000000000 +0100
@@ -4,18 +4,18 @@
POSIX specification:
@url{http://www.opengroup.org/onlinepubs/9699919799/functions/mbsrtowcs.html}
-Gnulib module: ---
+Gnulib module: mbsrtowcs
Portability problems fixed by Gnulib:
@itemize
+...@item
+This function is missing on some platforms:
+HP-UX 11, IRIX 6.5, 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 6.5, Solaris 2.6, mingw, Interix 3.5.
-...@item
On Windows platforms, @code{wchar_t} is a 16-bit type and therefore cannot
accommodate all Unicode characters.
@end itemize
