master
  1/* Checking macros for stdlib functions.
  2   Copyright (C) 2005-2025 Free Software Foundation, Inc.
  3   This file is part of the GNU C Library.
  4
  5   The GNU C Library is free software; you can redistribute it and/or
  6   modify it under the terms of the GNU Lesser General Public
  7   License as published by the Free Software Foundation; either
  8   version 2.1 of the License, or (at your option) any later version.
  9
 10   The GNU C Library is distributed in the hope that it will be useful,
 11   but WITHOUT ANY WARRANTY; without even the implied warranty of
 12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 13   Lesser General Public License for more details.
 14
 15   You should have received a copy of the GNU Lesser General Public
 16   License along with the GNU C Library; if not, see
 17   <https://www.gnu.org/licenses/>.  */
 18
 19#ifndef _STDLIB_H
 20# error "Never include <bits/stdlib.h> directly; use <stdlib.h> instead."
 21#endif
 22
 23extern char *__realpath_chk (const char *__restrict __name,
 24			     char *__restrict __resolved,
 25			     size_t __resolvedlen) __THROW __wur;
 26extern char *__REDIRECT_NTH (__realpath_alias,
 27			     (const char *__restrict __name,
 28			      char *__restrict __resolved), realpath) __wur;
 29extern char *__REDIRECT_NTH (__realpath_chk_warn,
 30			     (const char *__restrict __name,
 31			      char *__restrict __resolved,
 32			      size_t __resolvedlen), __realpath_chk) __wur
 33     __warnattr ("second argument of realpath must be either NULL or at "
 34		 "least PATH_MAX bytes long buffer");
 35
 36__fortify_function __attribute_overloadable__ __wur char *
 37__NTH (realpath (const char *__restrict __name,
 38		 __fortify_clang_overload_arg (char *, __restrict, __resolved)))
 39#if defined _LIBC_LIMITS_H_ && defined PATH_MAX
 40     __fortify_clang_warning_only_if_bos_lt (PATH_MAX, __resolved,
 41					     "second argument of realpath must be "
 42					     "either NULL or at least PATH_MAX "
 43					     "bytes long buffer")
 44#endif
 45{
 46  size_t __sz = __glibc_objsize (__resolved);
 47
 48  if (__sz == (size_t) -1)
 49    return __realpath_alias (__name, __resolved);
 50
 51#if !__fortify_use_clang && defined _LIBC_LIMITS_H_ && defined PATH_MAX
 52  if (__glibc_unsafe_len (PATH_MAX, sizeof (char), __sz))
 53    return __realpath_chk_warn (__name, __resolved, __sz);
 54#endif
 55  return __realpath_chk (__name, __resolved, __sz);
 56}
 57
 58
 59extern int __ptsname_r_chk (int __fd, char *__buf, size_t __buflen,
 60			    size_t __nreal) __THROW __nonnull ((2))
 61    __attr_access ((__write_only__, 2, 3));
 62extern int __REDIRECT_NTH (__ptsname_r_alias, (int __fd, char *__buf,
 63					       size_t __buflen), ptsname_r)
 64     __nonnull ((2)) __attr_access ((__write_only__, 2, 3));
 65extern int __REDIRECT_NTH (__ptsname_r_chk_warn,
 66			   (int __fd, char *__buf, size_t __buflen,
 67			    size_t __nreal), __ptsname_r_chk)
 68     __nonnull ((2)) __warnattr ("ptsname_r called with buflen bigger than "
 69				 "size of buf");
 70
 71__fortify_function __attribute_overloadable__ int
 72__NTH (ptsname_r (int __fd,
 73		 __fortify_clang_overload_arg (char *, ,__buf),
 74		 size_t __buflen))
 75     __fortify_clang_warning_only_if_bos_lt (__buflen, __buf,
 76					     "ptsname_r called with buflen "
 77					     "bigger than size of buf")
 78{
 79  return __glibc_fortify (ptsname_r, __buflen, sizeof (char),
 80			  __glibc_objsize (__buf),
 81			  __fd, __buf, __buflen);
 82}
 83
 84
 85extern int __wctomb_chk (char *__s, wchar_t __wchar, size_t __buflen)
 86  __THROW __wur;
 87extern int __REDIRECT_NTH (__wctomb_alias, (char *__s, wchar_t __wchar),
 88			   wctomb) __wur;
 89
 90__fortify_function __attribute_overloadable__ __wur int
 91__NTH (wctomb (__fortify_clang_overload_arg (char *, ,__s), wchar_t __wchar))
 92{
 93  /* We would have to include <limits.h> to get a definition of MB_LEN_MAX.
 94     But this would only disturb the namespace.  So we define our own
 95     version here.  */
 96#define __STDLIB_MB_LEN_MAX	16
 97#if defined MB_LEN_MAX && MB_LEN_MAX != __STDLIB_MB_LEN_MAX
 98# error "Assumed value of MB_LEN_MAX wrong"
 99#endif
100  if (__glibc_objsize (__s) != (size_t) -1
101      && __STDLIB_MB_LEN_MAX > __glibc_objsize (__s))
102    return __wctomb_chk (__s, __wchar, __glibc_objsize (__s));
103  return __wctomb_alias (__s, __wchar);
104}
105
106
107extern size_t __mbstowcs_chk (wchar_t *__restrict __dst,
108			      const char *__restrict __src,
109			      size_t __len, size_t __dstlen) __THROW
110    __attr_access ((__write_only__, 1, 3)) __attr_access ((__read_only__, 2));
111extern size_t __REDIRECT_NTH (__mbstowcs_nulldst,
112			      (wchar_t *__restrict __dst,
113			       const char *__restrict __src,
114			       size_t __len), mbstowcs)
115    __attr_access ((__read_only__, 2));
116extern size_t __REDIRECT_NTH (__mbstowcs_alias,
117			      (wchar_t *__restrict __dst,
118			       const char *__restrict __src,
119			       size_t __len), mbstowcs)
120    __attr_access ((__write_only__, 1, 3)) __attr_access ((__read_only__, 2));
121extern size_t __REDIRECT_NTH (__mbstowcs_chk_warn,
122			      (wchar_t *__restrict __dst,
123			       const char *__restrict __src,
124			       size_t __len, size_t __dstlen), __mbstowcs_chk)
125     __warnattr ("mbstowcs called with dst buffer smaller than len "
126		 "* sizeof (wchar_t)");
127
128__fortify_function __attribute_overloadable__ size_t
129__NTH (mbstowcs (__fortify_clang_overload_arg (wchar_t *, __restrict, __dst),
130		 const char *__restrict __src,
131		 size_t __len))
132     __fortify_clang_warning_only_if_bos0_lt2 (__len, __dst, sizeof (wchar_t),
133					       "mbstowcs called with dst buffer "
134					       "smaller than len * sizeof (wchar_t)")
135{
136  if (__builtin_constant_p (__dst == NULL) && __dst == NULL)
137    return __mbstowcs_nulldst (__dst, __src, __len);
138  else
139    return __glibc_fortify_n (mbstowcs, __len, sizeof (wchar_t),
140			      __glibc_objsize (__dst), __dst, __src, __len);
141}
142
143extern size_t __wcstombs_chk (char *__restrict __dst,
144			      const wchar_t *__restrict __src,
145			      size_t __len, size_t __dstlen) __THROW
146  __attr_access ((__write_only__, 1, 3)) __attr_access ((__read_only__, 2));
147extern size_t __REDIRECT_NTH (__wcstombs_alias,
148			      (char *__restrict __dst,
149			       const wchar_t *__restrict __src,
150			       size_t __len), wcstombs)
151  __attr_access ((__write_only__, 1, 3)) __attr_access ((__read_only__, 2));
152extern size_t __REDIRECT_NTH (__wcstombs_chk_warn,
153			      (char *__restrict __dst,
154			       const wchar_t *__restrict __src,
155			       size_t __len, size_t __dstlen), __wcstombs_chk)
156     __warnattr ("wcstombs called with dst buffer smaller than len");
157
158__fortify_function __attribute_overloadable__ size_t
159__NTH (wcstombs (__fortify_clang_overload_arg (char *, __restrict, __dst),
160		 const wchar_t *__restrict __src,
161		 size_t __len))
162{
163  return __glibc_fortify (wcstombs, __len, sizeof (char),
164			  __glibc_objsize (__dst),
165			  __dst, __src, __len);
166}