glibc/wcsmbs/mbsrtowcs_l.c

161 lines
4.6 KiB
C

/* Copyright (C) 2002-2024 Free Software Foundation, Inc.
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 <ctype.h>
#include <string.h>
#include "wcsmbsload.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
size_t
attribute_hidden
__mbsrtowcs_l (wchar_t *dst, const char **src, size_t len, mbstate_t *ps,
locale_t l)
{
struct __gconv_step_data data;
size_t result;
int status;
struct __gconv_step *towc;
size_t non_reversible;
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;
/* Get the conversion functions. */
fcts = get_gconv_fcts (l->__locales[LC_CTYPE]);
/* Get the structure with the function pointers. */
towc = fcts->towc;
__gconv_fct fct = towc->__fct;
if (towc->__shlib_handle != NULL)
PTR_DEMANGLE (fct);
/* We have to handle DST == NULL special. */
if (dst == NULL)
{
mbstate_t temp_state;
wchar_t buf[64]; /* Just an arbitrary size. */
const unsigned char *inbuf = (const unsigned char *) *src;
const unsigned char *srcend = inbuf + strlen (*src) + 1;
temp_state = *data.__statep;
data.__statep = &temp_state;
result = 0;
data.__outbufend = (unsigned char *) buf + sizeof (buf);
do
{
data.__outbuf = (unsigned char *) buf;
status = DL_CALL_FCT (fct, (towc, &data, &inbuf, srcend, NULL,
&non_reversible, 0, 1));
result += (wchar_t *) data.__outbuf - buf;
}
while (status == __GCONV_FULL_OUTPUT);
if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
{
/* There better should be a NUL wide char at the end. */
assert (((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. */
const unsigned char *srcp = (const unsigned char *) *src;
const unsigned char *srcend;
data.__outbuf = (unsigned char *) dst;
data.__outbufend = data.__outbuf + len * sizeof (wchar_t);
status = __GCONV_FULL_OUTPUT;
while (len > 0)
{
/* Pessimistic guess as to how much input we can use. In the
worst case we need one input byte for one output wchar_t. */
srcend = srcp + __strnlen ((const char *) srcp, len) + 1;
status = DL_CALL_FCT (fct, (towc, &data, &srcp, srcend, NULL,
&non_reversible, 0, 1));
if ((status != __GCONV_EMPTY_INPUT
&& status != __GCONV_INCOMPLETE_INPUT)
/* Not all input read. */
|| srcp != srcend
/* Reached the end of the input. */
|| srcend[-1] == '\0')
break;
len = (wchar_t *) data.__outbufend - (wchar_t *) data.__outbuf;
}
/* Make the end if the input known to the caller. */
*src = (const char *) srcp;
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)
&& ((wchar_t *) dst)[result - 1] == L'\0')
{
assert (result > 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;
}