glibc/wcsmbs/wcrtomb.c

128 lines
3.5 KiB
C

/* Copyright (C) 1996-2024 Free Software Foundation, Inc.
Copyright The GNU Toolchain Authors.
This file is part of the GNU C Library.
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, see
<https://www.gnu.org/licenses/>. */
#include <assert.h>
#include <dlfcn.h>
#include <errno.h>
#include <gconv.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <wcsmbsload.h>
#include <pointer_guard.h>
#ifndef EILSEQ
# define EILSEQ EINVAL
#endif
/* This is the private state used if PS is NULL. */
static mbstate_t state;
size_t
__wcrtomb_internal (char *s, wchar_t wc, mbstate_t *ps, size_t s_size)
{
char buf[MB_LEN_MAX];
struct __gconv_step_data data;
int status;
size_t result;
size_t dummy;
const struct gconv_fcts *fcts;
/* Set information for this step. */
data.__invocation_counter = 0;
data.__internal_use = 1;
data.__flags = __GCONV_IS_LAST;
data.__statep = ps ?: &state;
/* A first special case is if S is NULL. This means put PS in the
initial state. */
if (s == NULL)
wc = L'\0';
/* Tell where we want to have the result. */
data.__outbuf = (unsigned char *) buf;
data.__outbufend = (unsigned char *) buf + sizeof buf;
/* Get the conversion functions. */
fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
__gconv_fct fct = fcts->tomb->__fct;
if (fcts->tomb->__shlib_handle != NULL)
PTR_DEMANGLE (fct);
/* If WC is the NUL character we write into the output buffer the byte
sequence necessary for PS to get into the initial state, followed
by a NUL byte. */
if (wc == L'\0')
{
status = DL_CALL_FCT (fct, (fcts->tomb, &data, NULL, NULL,
NULL, &dummy, 1, 1));
if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
*data.__outbuf++ = '\0';
}
else
{
/* Do a normal conversion. */
const unsigned char *inbuf = (const unsigned char *) &wc;
status = DL_CALL_FCT (fct,
(fcts->tomb, &data, &inbuf,
inbuf + sizeof (wchar_t), NULL, &dummy, 0, 1));
}
/* There must not be any problems with the conversion but illegal input
characters. The output buffer must be large enough, otherwise the
definition of MB_CUR_MAX is not correct. All the other possible
errors also must not happen. */
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_EMPTY_INPUT
|| status == __GCONV_FULL_OUTPUT)
{
result = data.__outbuf - (unsigned char *) buf;
if (s != NULL)
{
if (result > s_size)
__chk_fail ();
memcpy (s, buf, result);
}
}
else
{
result = (size_t) -1;
__set_errno (EILSEQ);
}
return result;
}
size_t
__wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
{
return __wcrtomb_internal (s, wc, ps, (size_t) -1);
}
weak_alias (__wcrtomb, wcrtomb)
libc_hidden_weak (wcrtomb)