new module 'mbsnrtowcs'

[Bruno Haible]

After mbsrtowcs comes mbsnrtowcs. I'm committing a module that provides this
function.


2008-12-21  Bruno Haible  <address@hidden>

        New module 'mbsnrtowcs'.
        * lib/wchar.in.h (mbsnrtowcs): New declaration.
        * lib/mbsnrtowcs.c: New file.
        * lib/mbsrtowcs-state.c: New file.
        * lib/mbsrtowcs.c: Refer to _gl_mbsrtowcs_state.
        (internal_state): Remove variable.
        * m4/mbsnrtowcs.m4: New file.
        * m4/mbsrtowcs.m4 (gl_FUNC_MBSRTOWCS): Add mbsrtowcs-state.c to the
        compilation units.
        * m4/wchar.m4 (gl_WCHAR_H_DEFAULTS): Initialize GNULIB_MBSNRTOWCS,
        HAVE_MBSNRTOWCS, REPLACE_MBSNRTOWCS.
        * modules/wchar (Makefile.am): Substitute GNULIB_MBSNRTOWCS,
        HAVE_MBSNRTOWCS, REPLACE_MBSNRTOWCS.
        * modules/mbsnrtowcs: New file.
        * modules/mbsrtowcs (Files): Add lib/mbsrtowcs-state.c.
        * doc/posix-functions/mbsnrtowcs.texi: Mention the new module and a
        portability problem.

============================== lib/mbsnrtowcs.c ==============================
/* Convert string to wide string.
   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 <errno.h>
#include <limits.h>
#include <stdlib.h>

#include "minmax.h"
#include "strnlen1.h"


extern mbstate_t _gl_mbsrtowcs_state;

size_t
mbsnrtowcs (wchar_t *dest, const char **srcp, size_t srclen, size_t len, 
mbstate_t *ps)
{
  if (ps == NULL)
    ps = &_gl_mbsrtowcs_state;
  {
    const char *src = *srcp;

    if (dest != NULL)
      {
        wchar_t *destptr = dest;

        for (; srclen > 0 && len > 0; destptr++, len--)
          {
            size_t src_avail;
            size_t ret;

            /* An optimized variant of
               src_avail = strnlen1 (src, MIN (srclen, MB_LEN_MAX));  */
            if (srclen == 1 || src[0] == '\0')
              src_avail = 1;
            else if (srclen == 2 || src[1] == '\0')
              src_avail = 2;
            else if (srclen == 3 || src[2] == '\0')
              src_avail = 3;
            else if (MB_LEN_MAX <= 4 || srclen == 4 || src[3] == '\0')
              src_avail = 4;
            else
              src_avail = 4 + strnlen1 (src + 4, MIN (srclen, 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;
            srclen -= 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 (; srclen > 0; totalcount++)
          {
            size_t src_avail;
            size_t ret;

            /* An optimized variant of
               src_avail = strnlen1 (src, MIN (srclen, MB_LEN_MAX));  */
            if (srclen == 1 || src[0] == '\0')
              src_avail = 1;
            else if (srclen == 2 || src[1] == '\0')
              src_avail = 2;
            else if (srclen == 3 || src[2] == '\0')
              src_avail = 3;
            else if (MB_LEN_MAX <= 4 || srclen == 4 || src[3] == '\0')
              src_avail = 4;
            else
              src_avail = 4 + strnlen1 (src + 4, MIN (srclen, 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;
            srclen -= ret;
          }

        return totalcount;
      }

   bad_input:
    *srcp = src;
   bad_input2:
    errno = EILSEQ;
    return (size_t)(-1);
  }
}
=========================== lib/mbsrtowcs-state.c ============================
/* Convert string to wide string.
   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>

#include <wchar.h>

/* Internal state used by the functions mbsrtowcs() and mbsnrtowcs().  */
mbstate_t _gl_mbsrtowcs_state;
============================== m4/mbsnrtowcs.m4 ==============================
# mbsnrtowcs.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_MBSNRTOWCS],
[
  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])

  dnl Persuade glibc <wchar.h> to declare mbsnrtowcs().
  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

  AC_REQUIRE([AC_TYPE_MBSTATE_T])
  gl_MBSTATE_T_BROKEN
  if test $REPLACE_MBSTATE_T = 1; then
    REPLACE_MBSNRTOWCS=1
  fi
  AC_CHECK_FUNCS_ONCE([mbsnrtowcs])
  if test $ac_cv_func_mbsnrtowcs = no; then
    HAVE_MBSNRTOWCS=0
  fi
  if test $HAVE_MBSNRTOWCS = 0 || test $REPLACE_MBSNRTOWCS = 1; then
    gl_REPLACE_WCHAR_H
    AC_LIBOBJ([mbsnrtowcs])
    AC_LIBOBJ([mbsrtowcs-state])
    gl_PREREQ_MBSNRTOWCS
  fi
])

# Prerequisites of lib/mbsnrtowcs.c.
AC_DEFUN([gl_PREREQ_MBSNRTOWCS], [
  :
])
============================= modules/mbsnrtowcs =============================
Description:
mbsnrtowcs() function: convert string to wide string.

Files:
lib/mbsnrtowcs.c
lib/mbsrtowcs-state.c
m4/mbsnrtowcs.m4
m4/mbstate_t.m4

Depends-on:
extensions
wchar
mbrtowc
minmax
strnlen1

configure.ac:
gl_FUNC_MBSNRTOWCS
gl_WCHAR_MODULE_INDICATOR([mbsnrtowcs])

Makefile.am:

Include:
<wchar.h>

License:
LGPL

Maintainer:
Bruno Haible

==============================================================================
--- lib/wchar.in.h.orig 2008-12-21 14:32:12.000000000 +0100
+++ lib/wchar.in.h      2008-12-21 13:37:35.000000000 +0100
@@ -183,6 +183,24 @@
 #endif
 
 
+/* Convert a string to a wide string.  */
+#if @GNULIB_MBSNRTOWCS@
+# if @REPLACE_MBSNRTOWCS@
+#  undef mbsnrtowcs
+#  define mbsnrtowcs rpl_mbsnrtowcs
+# endif
+# if address@hidden@ || @REPLACE_MBSNRTOWCS@
+extern size_t mbsnrtowcs (wchar_t *dest, const char **srcp, size_t srclen, 
size_t len, mbstate_t *ps);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef mbsnrtowcs
+# define mbsnrtowcs(d,s,n,l,p) \
+    (GL_LINK_WARNING ("mbsnrtowcs is unportable - " \
+                      "use gnulib module mbsnrtowcs for portability"), \
+     mbsnrtowcs (d, s, n, l, p))
+#endif
+
+
 /* Return the number of screen columns needed for WC.  */
 #if @GNULIB_WCWIDTH@
 # if @REPLACE_WCWIDTH@
--- lib/mbsrtowcs.c.orig        2008-12-21 14:32:12.000000000 +0100
+++ lib/mbsrtowcs.c     2008-12-21 13:37:35.000000000 +0100
@@ -27,13 +27,13 @@
 #include "strnlen1.h"
 
 
-static mbstate_t internal_state;
+extern mbstate_t _gl_mbsrtowcs_state;
 
 size_t
 mbsrtowcs (wchar_t *dest, const char **srcp, size_t len, mbstate_t *ps)
 {
   if (ps == NULL)
-    ps = &internal_state;
+    ps = &_gl_mbsrtowcs_state;
   {
     const char *src = *srcp;
 
--- m4/mbsrtowcs.m4.orig        2008-12-21 14:32:12.000000000 +0100
+++ m4/mbsrtowcs.m4     2008-12-21 13:38:03.000000000 +0100
@@ -1,4 +1,4 @@
-# mbsrtowcs.m4 serial 3
+# mbsrtowcs.m4 serial 4
 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,
@@ -27,6 +27,7 @@
   if test $HAVE_MBSRTOWCS = 0 || test $REPLACE_MBSRTOWCS = 1; then
     gl_REPLACE_WCHAR_H
     AC_LIBOBJ([mbsrtowcs])
+    AC_LIBOBJ([mbsrtowcs-state])
     gl_PREREQ_MBSRTOWCS
   fi
 ])
--- m4/wchar.m4.orig    2008-12-21 14:32:12.000000000 +0100
+++ m4/wchar.m4 2008-12-21 13:37:35.000000000 +0100
@@ -7,7 +7,7 @@
 
 dnl Written by Eric Blake.
 
-# wchar.m4 serial 15
+# wchar.m4 serial 16
 
 AC_DEFUN([gl_WCHAR_H],
 [
@@ -67,6 +67,7 @@
   GNULIB_MBRTOWC=0;    AC_SUBST([GNULIB_MBRTOWC])
   GNULIB_MBRLEN=0;     AC_SUBST([GNULIB_MBRLEN])
   GNULIB_MBSRTOWCS=0;  AC_SUBST([GNULIB_MBSRTOWCS])
+  GNULIB_MBSNRTOWCS=0; AC_SUBST([GNULIB_MBSNRTOWCS])
   GNULIB_WCWIDTH=0;    AC_SUBST([GNULIB_WCWIDTH])
   dnl Assume proper GNU behavior unless another module says otherwise.
   HAVE_BTOWC=1;        AC_SUBST([HAVE_BTOWC])
@@ -74,6 +75,7 @@
   HAVE_MBRTOWC=1;      AC_SUBST([HAVE_MBRTOWC])
   HAVE_MBRLEN=1;       AC_SUBST([HAVE_MBRLEN])
   HAVE_MBSRTOWCS=1;    AC_SUBST([HAVE_MBSRTOWCS])
+  HAVE_MBSNRTOWCS=1;   AC_SUBST([HAVE_MBSNRTOWCS])
   HAVE_DECL_WCTOB=1;   AC_SUBST([HAVE_DECL_WCTOB])
   HAVE_DECL_WCWIDTH=1; AC_SUBST([HAVE_DECL_WCWIDTH])
   REPLACE_MBSTATE_T=0; AC_SUBST([REPLACE_MBSTATE_T])
@@ -81,6 +83,7 @@
   REPLACE_MBSINIT=0;   AC_SUBST([REPLACE_MBSINIT])
   REPLACE_MBRTOWC=0;   AC_SUBST([REPLACE_MBRTOWC])
   REPLACE_MBSRTOWCS=0; AC_SUBST([REPLACE_MBSRTOWCS])
+  REPLACE_MBSNRTOWCS=0;AC_SUBST([REPLACE_MBSNRTOWCS])
   REPLACE_WCWIDTH=0;   AC_SUBST([REPLACE_WCWIDTH])
   WCHAR_H='';          AC_SUBST([WCHAR_H])
 ])
--- modules/wchar.orig  2008-12-21 14:32:12.000000000 +0100
+++ modules/wchar       2008-12-21 13:37:35.000000000 +0100
@@ -31,6 +31,7 @@
              -e 's|@''GNULIB_MBRTOWC''@|$(GNULIB_MBRTOWC)|g' \
              -e 's|@''GNULIB_MBRLEN''@|$(GNULIB_MBRLEN)|g' \
              -e 's|@''GNULIB_MBSRTOWCS''@|$(GNULIB_MBSRTOWCS)|g' \
+             -e 's|@''GNULIB_MBSNRTOWCS''@|$(GNULIB_MBSNRTOWCS)|g' \
              -e 's|@''GNULIB_WCWIDTH''@|$(GNULIB_WCWIDTH)|g' \
              -e 's|@''HAVE_WINT_T''@|$(HAVE_WINT_T)|g' \
              -e 's|@''HAVE_BTOWC''@|$(HAVE_BTOWC)|g' \
@@ -38,6 +39,7 @@
              -e 's|@''HAVE_MBRTOWC''@|$(HAVE_MBRTOWC)|g' \
              -e 's|@''HAVE_MBRLEN''@|$(HAVE_MBRLEN)|g' \
              -e 's|@''HAVE_MBSRTOWCS''@|$(HAVE_MBSRTOWCS)|g' \
+             -e 's|@''HAVE_MBSNRTOWCS''@|$(HAVE_MBSNRTOWCS)|g' \
              -e 's|@''HAVE_DECL_WCTOB''@|$(HAVE_DECL_WCTOB)|g' \
              -e 's|@''HAVE_DECL_WCWIDTH''@|$(HAVE_DECL_WCWIDTH)|g' \
              -e 's|@''REPLACE_MBSTATE_T''@|$(REPLACE_MBSTATE_T)|g' \
@@ -45,6 +47,7 @@
              -e 's|@''REPLACE_MBSINIT''@|$(REPLACE_MBSINIT)|g' \
              -e 's|@''REPLACE_MBRTOWC''@|$(REPLACE_MBRTOWC)|g' \
              -e 's|@''REPLACE_MBSRTOWCS''@|$(REPLACE_MBSRTOWCS)|g' \
+             -e 's|@''REPLACE_MBSNRTOWCS''@|$(REPLACE_MBSNRTOWCS)|g' \
              -e 's|@''REPLACE_WCWIDTH''@|$(REPLACE_WCWIDTH)|g' \
              -e '/definition of GL_LINK_WARNING/r $(LINK_WARNING_H)' \
            < $(srcdir)/wchar.in.h; \
--- modules/mbsrtowcs.orig      2008-12-21 14:32:12.000000000 +0100
+++ modules/mbsrtowcs   2008-12-21 13:37:35.000000000 +0100
@@ -3,6 +3,7 @@
 
 Files:
 lib/mbsrtowcs.c
+lib/mbsrtowcs-state.c
 m4/mbsrtowcs.m4
 m4/mbstate_t.m4
 m4/locale-fr.m4
--- doc/posix-functions/mbsnrtowcs.texi.orig    2008-12-21 14:32:12.000000000 
+0100
+++ doc/posix-functions/mbsnrtowcs.texi 2008-12-21 13:37:35.000000000 +0100
@@ -4,15 +4,21 @@
 
 POSIX specification: 
@url{http://www.opengroup.org/onlinepubs/9699919799/functions/mbsnrtowcs.html}
 
-Gnulib module: ---
+Gnulib module: mbsnrtowcs
 
 Portability problems fixed by Gnulib:
 @itemize
address@hidden
+This function is missing on some platforms:
+MacOS X 10.3, FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, AIX 4.3.2, HP-UX 11, 
IRIX 6.5, OSF/1 5.1, Solaris 10, Cygwin, mingw, Interix 3.5, BeOS.
 @end itemize
 
 Portability problems not fixed by Gnulib:
 @itemize
 @item
-This function is missing on some platforms:
-MacOS X 10.3, FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, AIX 4.3.2, HP-UX 11, 
IRIX 6.5, OSF/1 5.1, Solaris 10, Cygwin, mingw, Interix 3.5, BeOS.
+The specification is not clear about whether this function should update the
+conversion state when the first argument (the destination pointer) is NULL.
+The glibc, MacOS X, FreeBSD implementations do update the state in this case.
+For portability, when passing a NULL destination argument, it is best to pass
+a pointer to a temporary copy of the conversion state.
 @end itemize