1/* Routines for dealing with '\0' separated environment vectors
 2   Copyright (C) 1995-2025 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 _ENVZ_H
20#define _ENVZ_H	1
21
22#include <features.h>
23
24#include <errno.h>
25
26/* Envz's are argz's too, and should be created etc., using the same
27   routines.  */
28#include <argz.h>
29
30__BEGIN_DECLS
31
32/* Returns a pointer to the entry in ENVZ for NAME, or 0 if there is none.  */
33extern char *envz_entry (const char *__restrict __envz, size_t __envz_len,
34			 const char *__restrict __name)
35     __THROW __attribute_pure__;
36
37/* Returns a pointer to the value portion of the entry in ENVZ for NAME, or 0
38   if there is none.  */
39extern char *envz_get (const char *__restrict __envz, size_t __envz_len,
40		       const char *__restrict __name)
41     __THROW __attribute_pure__;
42
43/* Adds an entry for NAME with value VALUE to ENVZ & ENVZ_LEN.  If an entry
44   with the same name already exists in ENVZ, it is removed.  If VALUE is
45   NULL, then the new entry will a special null one, for which envz_get will
46   return NULL, although envz_entry will still return an entry; this is handy
47   because when merging with another envz, the null entry can override an
48   entry in the other one.  Null entries can be removed with envz_strip ().  */
49extern error_t envz_add (char **__restrict __envz,
50			 size_t *__restrict __envz_len,
51			 const char *__restrict __name,
52			 const char *__restrict __value) __THROW;
53
54/* Adds each entry in ENVZ2 to ENVZ & ENVZ_LEN, as if with envz_add().  If
55   OVERRIDE is true, then values in ENVZ2 will supersede those with the same
56   name in ENV, otherwise not.  */
57extern error_t envz_merge (char **__restrict __envz,
58			   size_t *__restrict __envz_len,
59			   const char *__restrict __envz2,
60			   size_t __envz2_len, int __override) __THROW;
61
62/* Remove the entry for NAME from ENVZ & ENVZ_LEN, if any.  */
63extern void envz_remove (char **__restrict __envz,
64			 size_t *__restrict __envz_len,
65			 const char *__restrict __name) __THROW;
66
67/* Remove null entries.  */
68extern void envz_strip (char **__restrict __envz,
69			size_t *__restrict __envz_len) __THROW;
70
71__END_DECLS
72
73#endif /* envz.h */