1 /* Common code for DB-based databases in nss_db module.
2 Copyright (C) 1996 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
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 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
22 #include <libc-lock.h>
25 /* These symbols are defined by the including source file:
27 ENTNAME -- database name of the structure and functions (hostent, pwent).
28 STRUCTURE -- struct name, define only if not ENTNAME (passwd, group).
29 DATABASE -- database file name, ("hosts", "passwd")
31 NEED_H_ERRNO - defined iff an arg `int *herrnop' is used.
34 #define ENTNAME_r CONCAT(ENTNAME,_r)
37 #define DBFILE _PATH_VARDB DATABASE ".db"
40 #define H_ERRNO_PROTO , int *herrnop
41 #define H_ERRNO_ARG , herrnop
42 #define H_ERRNO_SET(val) (*herrnop = (val))
46 #define H_ERRNO_SET(val) ((void) 0)
49 /* Locks the static variables in this file. */
50 __libc_lock_define_initialized (static, lock
)
52 /* Maintenance of the shared handle open on the database. */
56 static unsigned int entidx
; /* Index for `getENTNAME'. */
58 /* Open database file if not already opened. */
59 static enum nss_status
60 internal_setent (int stayopen
)
62 enum nss_status status
= NSS_STATUS_SUCCESS
;
66 db
= dbopen (DBFILE
, O_RDONLY
, 0, DB_BTREE
, NULL
);
69 status
= NSS_STATUS_UNAVAIL
;
72 /* Remember STAYOPEN flag. */
80 /* Thread-safe, exported version of that. */
82 CONCAT(_nss_db_set
,ENTNAME
) (int stayopen
)
84 enum nss_status status
;
86 __libc_lock_lock (lock
);
88 status
= internal_setent (stayopen
);
90 /* Reset the sequential index. */
93 __libc_lock_unlock (lock
);
99 /* Close the database file. */
101 internal_endent (void)
111 /* Thread-safe, exported version of that. */
113 CONCAT(_nss_db_end
,ENTNAME
) (void)
115 __libc_lock_lock (lock
);
119 /* Reset STAYOPEN flag. */
122 __libc_lock_unlock (lock
);
124 return NSS_STATUS_SUCCESS
;
127 /* Do a database lookup for KEY. */
128 static enum nss_status
129 lookup (const DBT
*key
, struct STRUCTURE
*result
,
130 void *buffer
, int buflen H_ERRNO_PROTO
)
132 enum nss_status status
;
135 /* Open the database. */
136 status
= internal_setent (keep_db
);
137 if (status
!= NSS_STATUS_SUCCESS
)
140 /* Succeed iff it matches a value that parses correctly. */
141 status
= (((*db
->get
) (db
, key
, &value
, 0) == 0 &&
142 parse_line (value
.data
, result
, buffer
, buflen
))
143 ? NSS_STATUS_SUCCESS
: NSS_STATUS_NOTFOUND
);
152 /* Macro for defining lookup functions for this DB-based database.
154 NAME is the name of the lookup; e.g. `pwnam'.
156 KEYPATTERN gives `printf' args to construct a key string;
157 e.g. `(".%s", name)'.
159 KEYSIZE gives the allocation size of a buffer to construct it in;
160 e.g. `1 + strlen (name)'.
162 PROTO describes the arguments for the lookup key;
163 e.g. `const char *name'.
165 BREAK_IF_MATCH is ignored, but used by ../nss_files/files-XXX.c. */
167 #define DB_LOOKUP(name, keysize, keypattern, break_if_match, proto...) \
169 _nss_db_get##name##_r (proto, \
170 struct STRUCTURE *result, \
171 char *buffer, size_t buflen H_ERRNO_PROTO) \
174 enum nss_status status; \
175 const size_t size = (keysize); \
176 key.data = __alloca (size); \
177 key.size = KEYPRINTF keypattern; \
178 __libc_lock_lock (lock); \
179 status = lookup (&key, result, buffer, buflen H_ERRNO_ARG); \
180 __libc_lock_unlock (lock); \
184 #define KEYPRINTF(pattern, args...) snprintf (key.data, size, pattern ,##args)
189 /* Return the next entry from the database file, doing locking. */
191 CONCAT(_nss_db_get
,ENTNAME_r
) (struct STRUCTURE
*result
,
192 char *buffer
, size_t buflen H_ERRNO_PROTO
)
194 /* Return next entry in host file. */
195 enum nss_status status
;
199 __libc_lock_lock (lock
);
200 key
.size
= 1 + snprintf (key
.data
= buf
, sizeof buf
, "0%u", entidx
++);
201 status
= lookup (&key
, result
, buffer
, buflen H_ERRNO_ARG
);
202 __libc_lock_unlock (lock
);