1/* Copyright (C) 1991-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#if defined _AIX && !defined __GNUC__
19 #pragma alloca
20#endif
21
22#if HAVE_CONFIG_H
23# include <config.h>
24#endif
25
26#if _LIBC || HAVE_STDLIB_H
27# include <stdlib.h>
28#endif
29#if _LIBC || HAVE_STRING_H
30# include <string.h>
31#endif
32
33#if !__GNU_LIBRARY__ && !HAVE_STRCHR
34# define strchr index
35#endif
36
37#ifndef _LIBC
38# ifdef HAVE_ALLOCA_H
39# include <alloca.h>
40# else
41# ifdef __GNUC__
42# define alloca __builtin_alloca
43# else
44extern char *alloca ();
45# endif /* __GNUC__ */
46# endif /* HAVE_ALLOCA_H */
47#endif /* _LIBC */
48
49
50/* Put STRING, which is of the form "NAME=VALUE", in the environment. */
51int
52putenv (char *string)
53{
54 const char *const name_end = strchr (string, '=');
55
56 if (name_end != NULL)
57 {
58 char *name;
59#ifdef _LIBC
60 int use_malloc = !__libc_use_alloca (name_end - string + 1);
61 if (__builtin_expect (use_malloc, 0))
62 {
63 name = __strndup (string, name_end - string);
64 if (name == NULL)
65 return -1;
66 }
67 else
68 name = strndupa (string, name_end - string);
69#else
70# define use_malloc 1
71 name = malloc (name_end - string + 1);
72 if (name == NULL)
73 return -1;
74 memcpy (name, string, name_end - string);
75 name[name_end - string] = '\0';
76#endif
77 int result = __add_to_environ (name, NULL, string, 1);
78
79 if (__glibc_unlikely (use_malloc))
80 free (name);
81
82 return result;
83 }
84
85 __unsetenv (string);
86 return 0;
87}
88