glibc/wcsmbs/mbsnrtowcs.c

141 lines
4.0 KiB
C

/* Copyright (C) 1996,1997,1998,1999,2000,2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gnu.org>, 1996.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <dlfcn.h>
#include <errno.h>
#include <gconv.h>
#include <string.h>
#include <wchar.h>
#include <wcsmbsload.h>
#include <assert.h>
#ifndef EILSEQ
# define EILSEQ EINVAL
#endif
/* This is the private state used if PS is NULL. */
static mbstate_t state;
/* This is a non-standard function but it is very useful in the
implementation of stdio because we have to deal with unterminated
buffers. At most NMC bytes will be converted. */
size_t
__mbsnrtowcs (dst, src, nmc, len, ps)
wchar_t *dst;
const char **src;
size_t nmc;
size_t len;
mbstate_t *ps;
{
const unsigned char *srcend;
struct __gconv_step_data data;
size_t result;
int status;
struct __gconv_step *towc;
size_t dummy;
const struct gconv_fcts *fcts;
/* Tell where we want the result. */
data.__invocation_counter = 0;
data.__internal_use = 1;
data.__flags = __GCONV_IS_LAST;
data.__statep = ps ?: &state;
data.__trans = NULL;
if (nmc == 0)
return 0;
srcend = *src + __strnlen (*src, nmc - 1) + 1;
/* Get the conversion functions. */
fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
/* Get the structure with the function pointers. */
towc = fcts->towc;
/* We have to handle DST == NULL special. */
if (dst == NULL)
{
wchar_t buf[64]; /* Just an arbitrary size. */
const unsigned char *inbuf = *src;
result = 0;
data.__outbufend = (unsigned char *) buf + sizeof (buf);
do
{
data.__outbuf = (unsigned char *) buf;
status = DL_CALL_FCT (towc->__fct,
(towc, &data, &inbuf, srcend, NULL,
&dummy, 0, 1));
result += (wchar_t *) data.__outbuf - buf;
}
while (status == __GCONV_FULL_OUTPUT);
if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
&& ((wchar_t *) data.__outbuf)[-1] == L'\0')
/* Don't count the NUL character in. */
--result;
}
else
{
/* This code is based on the safe assumption that all internal
multi-byte encodings use the NUL byte only to mark the end
of the string. */
data.__outbuf = (unsigned char *) dst;
data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
status = DL_CALL_FCT (towc->__fct,
(towc, &data, (const unsigned char **) src, srcend,
NULL, &dummy, 0, 1));
result = (wchar_t *) data.__outbuf - dst;
/* We have to determine whether the last character converted
is the NUL character. */
if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
&& (assert (result > 0),
((wchar_t *) dst)[result - 1] == L'\0'))
{
assert (__mbsinit (data.__statep));
*src = NULL;
--result;
}
}
/* There must not be any problems with the conversion but illegal input
characters. */
assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
|| status == __GCONV_ILLEGAL_INPUT
|| status == __GCONV_INCOMPLETE_INPUT
|| status == __GCONV_FULL_OUTPUT);
if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
&& status != __GCONV_EMPTY_INPUT && status != __GCONV_INCOMPLETE_INPUT)
{
result = (size_t) -1;
__set_errno (EILSEQ);
}
return result;
}
weak_alias (__mbsnrtowcs, mbsnrtowcs)