libstdc++: cstdlib Source File

libstdc++

cstdlib
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1// -*- C++ -*- forwarding header.
2
3// Copyright (C) 1997-2026 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library. This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23// <http://www.gnu.org/licenses/>.
24
25/** @file include/cstdlib
26 * This is a Standard C++ Library file. You should @c \#include this file
27 * in your programs, rather than any of the @a *.h implementation files.
28 *
29 * This is the C++ version of the Standard C Library header @c stdlib.h,
30 * and its contents are (mostly) the same as that header, but are all
31 * contained in the namespace @c std (except for names which are defined
32 * as macros in C).
33 */
34
35//
36// ISO C++ 14882: 20.4.6 C library
37//
38
39#ifndef _GLIBCXX_CSTDLIB
40#define _GLIBCXX_CSTDLIB 1
41
42#ifdef _GLIBCXX_SYSHDR
43#pragma GCC system_header
44#endif
45
46#include <bits/c++config.h>
47
48#if !_GLIBCXX_HOSTED
49// The C standard does not require a freestanding implementation to
50// provide <stdlib.h>. However, the C++ standard does still require
51// <cstdlib> -- but only the functionality mentioned in
52// [lib.support.start.term].
53
54#define EXIT_SUCCESS 0
55#define EXIT_FAILURE 1
56#define NULL __null
57
58namespace std
59{
60 extern "C" void abort(void) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
61 extern "C" int atexit(void (*)(void)) _GLIBCXX_NOTHROW;
62 extern "C" void exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
63#if __cplusplus >= 201103L
64# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
65 extern "C" int at_quick_exit(void (*)(void)) _GLIBCXX_NOTHROW;
66# endif
67# ifdef _GLIBCXX_HAVE_QUICK_EXIT
68 extern "C" void quick_exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
69# endif
70#if _GLIBCXX_USE_C99_STDLIB
71 extern "C" void _Exit(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
72#endif
73#endif
74} // namespace std
75
76#else
77
78// Need to ensure this finds the C library's <stdlib.h> not a libstdc++
79// wrapper that might already be installed later in the include search path.
80#pragma GCC diagnostic push
81#pragma GCC diagnostic ignored "-Wpedantic" // include_next
82#define _GLIBCXX_INCLUDE_NEXT_C_HEADERS
83#include_next <stdlib.h>
84#undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS
85#pragma GCC diagnostic pop
86
87#include <bits/std_abs.h>
88
89// Get rid of those macros defined in <stdlib.h> in lieu of real functions.
90#undef abort
91#if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC)
92# undef aligned_alloc
93#endif
94#undef atexit
95#if __cplusplus >= 201103L
96# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
97# undef at_quick_exit
98# endif
99#endif
100#undef atof
101#undef atoi
102#undef atol
103#undef bsearch
104#undef calloc
105#undef div
106#undef exit
107#undef free
108#undef getenv
109#undef labs
110#undef ldiv
111#undef malloc
112#undef mblen
113#undef mbstowcs
114#undef mbtowc
115#undef qsort
116#if __cplusplus >= 201103L
117# ifdef _GLIBCXX_HAVE_QUICK_EXIT
118# undef quick_exit
119# endif
120#endif
121#undef rand
122#undef realloc
123#undef srand
124#undef strtod
125#undef strtol
126#undef strtoul
127#undef system
128#undef wcstombs
129#undef wctomb
130
131extern "C++"
132{
133namespace std _GLIBCXX_VISIBILITY(default)
134{
135_GLIBCXX_BEGIN_NAMESPACE_VERSION
136
137 using ::div_t;
138 using ::ldiv_t;
139
140 using ::abort;
141#if __cplusplus >= 201703L && defined(_GLIBCXX_HAVE_ALIGNED_ALLOC)
142 using ::aligned_alloc;
143#endif
144 using ::atexit;
145#if __cplusplus >= 201103L
146# ifdef _GLIBCXX_HAVE_AT_QUICK_EXIT
147 using ::at_quick_exit;
148# endif
149#endif
150 using ::atof;
151 using ::atoi;
152 using ::atol;
153 using ::bsearch;
154 using ::calloc;
155 using ::div;
156 using ::exit;
157 using ::free;
158 using ::getenv;
159 using ::labs;
160 using ::ldiv;
161 using ::malloc;
162#ifdef _GLIBCXX_HAVE_MBSTATE_T
163 using ::mblen;
164 using ::mbstowcs;
165 using ::mbtowc;
166#endif // _GLIBCXX_HAVE_MBSTATE_T
167 using ::qsort;
168#if __cplusplus >= 201103L
169# ifdef _GLIBCXX_HAVE_QUICK_EXIT
170 using ::quick_exit;
171# endif
172#endif
173 using ::rand;
174 using ::realloc;
175 using ::srand;
176 using ::strtod;
177 using ::strtol;
178 using ::strtoul;
179 using ::system;
180#ifdef _GLIBCXX_USE_WCHAR_T
181 using ::wcstombs;
182 using ::wctomb;
183#endif // _GLIBCXX_USE_WCHAR_T
184
185#ifndef __CORRECT_ISO_CPP_STDLIB_H_PROTO
186 inline ldiv_t
187 div(long __i, long __j) _GLIBCXX_NOTHROW { return ldiv(__i, __j); }
188#endif
189
190
191_GLIBCXX_END_NAMESPACE_VERSION
192} // namespace
193
194#if _GLIBCXX_USE_C99_STDLIB
195
196#undef _Exit
197#undef llabs
198#undef lldiv
199#undef atoll
200#undef strtoll
201#undef strtoull
202#undef strtof
203#undef strtold
204
205namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
206{
207_GLIBCXX_BEGIN_NAMESPACE_VERSION
208
209#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
210 using ::lldiv_t;
211#endif
212#if _GLIBCXX_USE_C99_CHECK || _GLIBCXX_USE_C99_DYNAMIC
213 extern "C" void (_Exit)(int) _GLIBCXX_NOTHROW _GLIBCXX_NORETURN;
214#endif
215#if !_GLIBCXX_USE_C99_DYNAMIC
216 using ::_Exit;
217#endif
218
219#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
220#pragma GCC diagnostic push
221#pragma GCC diagnostic ignored "-Wlong-long"
222 using ::llabs;
223
224 inline lldiv_t
225 div(long long __n, long long __d)
226 { lldiv_t __q; __q.quot = __n / __d; __q.rem = __n % __d; return __q; }
227
228 using ::lldiv;
229#pragma GCC diagnostic pop
230#endif
231
232#if _GLIBCXX_USE_C99_LONG_LONG_CHECK || _GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
233 extern "C" long long int (atoll)(const char *) _GLIBCXX_NOTHROW;
234 extern "C" long long int
235 (strtoll)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW;
236 extern "C" unsigned long long int
237 (strtoull)(const char * __restrict, char ** __restrict, int) _GLIBCXX_NOTHROW;
238#endif
239#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
240 using ::atoll;
241 using ::strtoll;
242 using ::strtoull;
243#endif
244 using ::strtof;
245 using ::strtold;
246
247_GLIBCXX_END_NAMESPACE_VERSION
248} // namespace __gnu_cxx
249
250namespace std
251{
252#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
253 using ::__gnu_cxx::lldiv_t;
254#endif
255 using ::__gnu_cxx::_Exit;
256#if !_GLIBCXX_USE_C99_LONG_LONG_DYNAMIC
257 using ::__gnu_cxx::llabs;
258 using ::__gnu_cxx::div;
259 using ::__gnu_cxx::lldiv;
260#endif
261 using ::__gnu_cxx::atoll;
262 using ::__gnu_cxx::strtof;
263 using ::__gnu_cxx::strtoll;
264 using ::__gnu_cxx::strtoull;
265 using ::__gnu_cxx::strtold;
266} // namespace std
267
268#else // ! _GLIBCXX_USE_C99_STDLIB
269
270// We also check for strtof and strtold separately from _GLIBCXX_USE_C99_STDLIB
271
272#if _GLIBCXX_HAVE_STRTOF
273#undef strtof
274namespace std { using ::strtof; }
275#endif
276
277#if _GLIBCXX_HAVE_STRTOLD
278#undef strtold
279namespace std { using ::strtold; }
280#endif
281
282#endif // _GLIBCXX_USE_C99_STDLIB
283
284} // extern "C++"
285
286#endif // !_GLIBCXX_HOSTED
287
288#endif
std_abs.h
c++config.h
std
ISO C++ entities toplevel namespace is std.
__gnu_cxx
GNU extensions for public use.