diff options
Diffstat (limited to 'nss/nss_db/db-alias.c')
| -rw-r--r-- | nss/nss_db/db-alias.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/nss/nss_db/db-alias.c b/nss/nss_db/db-alias.c new file mode 100644 index 0000000000..2c44f4df79 --- /dev/null +++ b/nss/nss_db/db-alias.c @@ -0,0 +1,235 @@ +/* Mail alias file parser in nss_db module. + Copyright (C) 1996 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <aliases.h> +#include <alloca.h> +#include <ctype.h> +#include <db.h> +#include <errno.h> +#include <fcntl.h> +#include <libc-lock.h> +#include <paths.h> +#include <string.h> + +#include "nsswitch.h" + +/* Locks the static variables in this file. */ +__libc_lock_define_initialized (static, lock) + +/* Maintenance of the shared handle open on the database. */ + +static DB *db; +static int keep_db; +static unsigned int entidx; /* Index for `getaliasent_r'. */ + +/* Open database file if not already opened. */ +static enum nss_status +internal_setent (int stayopen) +{ + enum nss_status status = NSS_STATUS_SUCCESS; + + if (db == NULL) + { + db = dbopen (_PATH_VARDB "aliases.db", O_RDONLY, 0, DB_BTREE, NULL); + + if (db == NULL) + status = NSS_STATUS_UNAVAIL; + } + + /* Remember STAYOPEN flag. */ + if (db != NULL) + keep_db |= stayopen; + + return status; +} + + +/* Thread-safe, exported version of that. */ +enum nss_status +_nss_db_setaliasent (int stayopen) +{ + enum nss_status status; + + __libc_lock_lock (lock); + + status = internal_setent (stayopen); + + /* Reset the sequential index. */ + entidx = 0; + + __libc_lock_unlock (lock); + + return status; +} + + +/* Close the database file. */ +static void +internal_endent (void) +{ + if (db != NULL) + { + (*db->close) (db); + db = NULL; + } +} + + +/* Thread-safe, exported version of that. */ +enum nss_status +_nss_db_endaliasent (void) +{ + __libc_lock_lock (lock); + + internal_endent (); + + /* Reset STAYOPEN flag. */ + keep_db = 0; + + __libc_lock_unlock (lock); + + return NSS_STATUS_SUCCESS; +} + +/* We provide the parse function here. The parser in libnss_files + cannot be used. The generation of the db file already resolved all + :include: statements so we simply have to parse the list and store + the result. */ +static enum nss_status +lookup (const DBT *key, struct aliasent *result, char *buffer, + size_t buflen) +{ + enum nss_status status; + DBT value; + + /* Open the database. */ + status = internal_setent (keep_db); + if (status != NSS_STATUS_SUCCESS) + return status; + + if ((*db->get) (db, key, &value, 0) == 0) + { + const char *src = value.data; + + result->alias_members_len = 0; + + /* We now have to fill the BUFFER with all the information. */ + if (buflen < key->size + 1) + { + no_more_room: + __set_errno (ERANGE); + return NSS_STATUS_TRYAGAIN; + } + + if (status == NSS_STATUS_SUCCESS) + { + char *cp; + size_t cnt; + + buffer = stpncpy (buffer, key->data, key->size) + 1; + buflen -= key->size + 1; + + while (*src != '\0') + { + const char *end, *upto; + while (isspace (*src)) + ++src; + + end = strchr (src, ','); + if (end == NULL) + end = strchr (src, '\0'); + for (upto = end; upto > src && isspace (upto[-1]); --upto); + + if (upto != src) + { + if ((upto - src) + __alignof__ (char *) > buflen) + goto no_more_room; + buffer = stpncpy (buffer, src, upto - src) + 1; + buflen -= (upto - src) + __alignof (char *); + ++result->alias_members_len; + } + src = end + (*end != '\0'); + } + + /* Now prepare the return. Provide string pointers for the + currently selected aliases. */ + + /* Adjust the pointer so it is aligned for storing pointers. */ + buffer += __alignof__ (char *) - 1; + buffer -= ((buffer - (char *) 0) % __alignof__ (char *)); + result->alias_members = (char **) buffer; + + /* Compute addresses of alias entry strings. */ + cp = result->alias_name; + for (cnt = 0; cnt < result->alias_members_len; ++cnt) + { + cp = strchr (cp, '\0') + 1; + result->alias_members[cnt] = cp; + } + + status = (result->alias_members_len == 0 + ? NSS_STATUS_RETURN : NSS_STATUS_SUCCESS); + } + } + else + status = NSS_STATUS_NOTFOUND; + + if (! keep_db) + internal_endent (); + + return status; +} + +enum nss_status +_nss_db_getaliasent_r (struct aliasent *result, char *buffer, size_t buflen) +{ + /* Return next entry in host file. */ + enum nss_status status; + char buf[20]; + DBT key; + + __libc_lock_lock (lock); + key.size = 1 + snprintf (key.data = buf, sizeof buf, "0%u", entidx++); + status = lookup (&key, result, buffer, buflen); + __libc_lock_unlock (lock); + + return status; +} + + +enum nss_status +_nss_db_getaliasbyname_r (const char *name, struct aliasent *result, + char *buffer, size_t buflen) +{ + DBT key; + enum nss_status status; + + key.size = 1 + strlen (name); + + key.data = __alloca (key.size); + ((char *) key.data)[0] = '.'; + memcpy (&((char *) key.data)[1], name, key.size - 1); + + __libc_lock_lock (lock); + status = lookup (&key, result, buffer, buflen); + __libc_lock_unlock (lock); + + return status; +} |