1/* Copyright (C) 1996-2024 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#include <errno.h>
19#include <libc-lock.h>
20#include <stdlib.h>
21#include <set-freeres.h>
22
23#include "nsswitch.h"
24
25/*******************************************************************\
26|* Here we assume several symbols to be defined: *|
27|* *|
28|* LOOKUP_TYPE - the return type of the function *|
29|* *|
30|* GETFUNC_NAME - name of the non-reentrant getXXXent function *|
31|* *|
32|* BUFLEN - size of static buffer *|
33|* *|
34|* Optionally the following vars can be defined: *|
35|* *|
36|* NEED_H_ERRNO - an extra parameter will be passed to point to *|
37|* the global `h_errno' variable. *|
38|* *|
39\*******************************************************************/
40
41/* To make the real sources a bit prettier. */
42#define REENTRANT_GETNAME APPEND_R (GETFUNC_NAME)
43#define APPEND_R(name) APPEND_R1 (name)
44#define APPEND_R1(name) name##_r
45#define INTERNAL(name) INTERNAL1 (name)
46#define INTERNAL1(name) __##name
47#define APPEND_FREEMEM_NAME1(name) __libc_##name##_freemem_ptr
48#define APPEND_FREEMEM_NAME(name) APPEND_FREEMEM_NAME1(name)
49#define FREEMEM_NAME APPEND_FREEMEM_NAME (GETFUNC_NAME)
50
51/* Sometimes we need to store error codes in the `h_errno' variable. */
52#ifdef NEED_H_ERRNO
53# define H_ERRNO_PARM , int *h_errnop
54# define H_ERRNO_VAR &h_errno
55#else
56# define H_ERRNO_PARM
57# define H_ERRNO_VAR NULL
58#endif
59
60/* Prototype of the reentrant version. */
61extern int INTERNAL (REENTRANT_GETNAME) (LOOKUP_TYPE *resbuf, char *buffer,
62 size_t buflen, LOOKUP_TYPE **result
63 H_ERRNO_PARM) attribute_hidden;
64
65/* We need to protect the dynamic buffer handling. */
66__libc_lock_define_initialized (static, lock);
67
68/* This points to the static buffer used. */
69static char *buffer;
70
71weak_alias (buffer, FREEMEM_NAME)
72
73LOOKUP_TYPE *
74GETFUNC_NAME (void)
75{
76 static size_t buffer_size;
77 static union
78 {
79 LOOKUP_TYPE l;
80 void *ptr;
81 } resbuf;
82 LOOKUP_TYPE *result;
83 int save;
84
85 /* Get lock. */
86 __libc_lock_lock (lock);
87
88 result = (LOOKUP_TYPE *)
89 __nss_getent (func: (getent_r_function) INTERNAL (REENTRANT_GETNAME),
90 resbuf: &resbuf.ptr, buffer: &buffer, BUFLEN, buffer_size: &buffer_size,
91 H_ERRNO_VAR);
92
93 save = errno;
94 __libc_lock_unlock (lock);
95 __set_errno (save);
96 return result;
97}
98
99nss_interface_function (GETFUNC_NAME)
100

source code of glibc/nss/getXXent.c