libstdc++
cstring
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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 cstring
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 string.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_CSTRING
40 #define _GLIBCXX_CSTRING 1
41 
42 #ifdef _GLIBCXX_SYSHDR
43 #pragma GCC system_header
44 #endif
45 
46 #define __glibcxx_want_freestanding_cstring
47 #include <bits/version.h>
48 #include <string.h>
49 
50 // Get rid of those macros defined in <string.h> in lieu of real functions.
51 #undef memchr
52 #undef memcmp
53 #undef memcpy
54 #undef memmove
55 #undef memset
56 #undef strcat
57 #undef strchr
58 #undef strcmp
59 #undef strcoll
60 #undef strcpy
61 #undef strcspn
62 #undef strerror
63 #undef strlen
64 #undef strncat
65 #undef strncmp
66 #undef strncpy
67 #undef strpbrk
68 #undef strrchr
69 #undef strspn
70 #undef strstr
71 #undef strtok
72 #undef strxfrm
73 
74 extern "C++"
75 {
76 namespace std _GLIBCXX_VISIBILITY(default)
77 {
78 _GLIBCXX_BEGIN_NAMESPACE_VERSION
79 
80  using ::memchr;
81  using ::memcmp;
82  using ::memcpy;
83  using ::memmove;
84  using ::memset;
85  using ::strcat;
86  using ::strcmp;
87  using ::strcoll;
88  using ::strcpy;
89  using ::strcspn;
90  using ::strerror;
91  using ::strlen;
92  using ::strncat;
93  using ::strncmp;
94  using ::strncpy;
95  using ::strspn;
96 #if _GLIBCXX_HOSTED || __cplusplus <= 202302L
97  using ::strtok;
98 #endif
99  using ::strxfrm;
100  using ::strchr;
101  using ::strpbrk;
102  using ::strrchr;
103  using ::strstr;
104 
105 #ifndef __CORRECT_ISO_CPP_STRING_H_PROTO
106  inline void*
107  memchr(void* __s, int __c, size_t __n)
108  { return __builtin_memchr(__s, __c, __n); }
109 
110  inline char*
111  strchr(char* __s, int __n)
112  { return __builtin_strchr(__s, __n); }
113 
114  inline char*
115  strpbrk(char* __s1, const char* __s2)
116  { return __builtin_strpbrk(__s1, __s2); }
117 
118  inline char*
119  strrchr(char* __s, int __n)
120  { return __builtin_strrchr(__s, __n); }
121 
122  inline char*
123  strstr(char* __s1, const char* __s2)
124  { return __builtin_strstr(__s1, __s2); }
125 #endif
126 
127 _GLIBCXX_END_NAMESPACE_VERSION
128 } // namespace
129 } // extern "C++"
130 
131 #endif
std
ISO C++ entities toplevel namespace is std.