+/*
+ * Copyright (c) 1995, the EUROPAGATE consortium (see below).
+ *
+ * The EUROPAGATE consortium members are:
+ *
+ * University College Dublin
+ * Danmarks Teknologiske Videnscenter
+ * An Chomhairle Leabharlanna
+ * Consejo Superior de Investigaciones Cientificas
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and
+ * its documentation, in whole or in part, for any purpose, is hereby granted,
+ * provided that:
+ *
+ * 1. This copyright and permission notice appear in all copies of the
+ * software and its documentation. Notices of copyright or attribution
+ * which appear at the beginning of any file must remain unchanged.
+ *
+ * 2. The names of EUROPAGATE or the project partners may not be used to
+ * endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * 3. Users of this software (implementors and gateway operators) agree to
+ * inform the EUROPAGATE consortium of their use of the software. This
+ * information will be used to evaluate the EUROPAGATE project and the
+ * software, and to plan further developments. The consortium may use
+ * the information in later publications.
+ *
+ * 4. Users of this software agree to make their best efforts, when
+ * documenting their use of the software, to acknowledge the EUROPAGATE
+ * consortium, and the role played by the software in their work.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS, IMPLIED, OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+ * IN NO EVENT SHALL THE EUROPAGATE CONSORTIUM OR ITS MEMBERS BE LIABLE
+ * FOR ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF
+ * ANY KIND, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA
+ * OR PROFITS, WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND
+ * ON ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
+ * USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
/* Gateway utility
* Europagate, 1995
*
* $Log: gw-db.c,v $
- * Revision 1.1 1995/03/27 08:25:01 adam
+ * Revision 1.5 1996/01/24 17:00:12 adam
+ * Bug fix: missing argument to gw_log-call.
+ *
+ * Revision 1.4 1995/12/20 16:28:07 adam
+ * Extra parameter block to gw_db_open. If block is 0 gw_db_open
+ * returns NULL if lock couldn't be satisfied.
+ * Minor changes in iso2709.c.
+ *
+ * Revision 1.3 1995/05/16 09:40:53 adam
+ * LICENSE.
+ *
+ * Revision 1.2 1995/05/01 12:43:57 adam
+ * lgets function moved from kernel to util.
+ *
+ * Revision 1.1 1995/03/27 08:25:01 adam
* New module gip: Gateway IPc module.
* New module gw-db: Gateway hash-db module (user information table).
*
#include <unistd.h>
#include <fcntl.h>
+#include <gw-log.h>
#include <gw-db.h>
#define FILE_HEAD_LEN 128
#define DB_HASH 1997
struct gw_db {
- struct file_head {
- char magic[8];
- int no_of_entries;
- int sequence_no;
+ struct file_head { /* file header info */
+ char magic[8]; /* start info */
+ int no_of_entries; /* no of entries in table */
+ int sequence_no; /* number of next to come */
} head;
- int *hash_array;
- int fd;
- int dirty;
+ int *hash_array; /* hash array pointers (DB_HASH in size) */
+ int fd; /* descriptor of file */
+ int dirty; /* any writes so far? */
};
-struct db_bucket {
- int name_length;
- int info_length;
- int next;
- int prev;
+struct db_bucket { /* information about individual entries */
+ int name_length; /* length of name */
+ int info_length; /* length of information */
+ int next; /* next in hash chain - possibly 0 */
+ int prev; /* prev in hach chain - possibly 0 */
};
+static char *mod = "gwdb";
+
+/*
+ * write_head: write header of table
+ */
static int write_head (GW_DB db)
{
char file_head_buf[FILE_HEAD_LEN];
return 0;
}
-static unsigned hash (const char *name)
+/*
+ * hash: calculate hash value
+ */
+static unsigned hash (const char *name, int length)
{
unsigned l = 0;
- while (*name)
+ while (--length >= 0)
l = l*65599 + *name++;
return l % DB_HASH;
}
-static void lock_file (int fd, int type)
+/*
+ * lock_file: lock entire file
+ */
+static int lock_file (int fd, int block, int type)
{
struct flock area;
area.l_type = type;
area.l_whence = SEEK_SET;
area.l_start = 0L;
area.l_len = 0L;
- fcntl (fd, F_SETLKW, &area);
+ return fcntl (fd, block ? F_SETLKW : F_SETLK, &area);
}
+
+/*
+ * gw_db_lookup: table lookup
+ */
int gw_db_lookup (GW_DB db, const char *name, int name_length,
void **buf, size_t *count)
{
struct db_bucket bucket;
- unsigned l = hash (name);
+ unsigned l = hash (name, name_length);
char *dbuf = NULL;
int dsize = 0;
int pos;
return 0;
}
+/*
+ * gw_db_insert: table insertion
+ */
int gw_db_insert (GW_DB db, const char *name, int name_length,
const void *buf, size_t count)
{
struct db_bucket n_bucket;
struct db_bucket bucket;
off_t n_pos, r_pos;
- unsigned l = hash (name);
+ unsigned l = hash (name, name_length);
int pos = db->hash_array[l];
int r;
return 0;
}
+/*
+ * gw_db_free: release memory associated with table
+ */
static GW_DB gw_db_free (GW_DB db)
{
free (db->hash_array);
return NULL;
}
-GW_DB gw_db_open (const char *fname, int write_flag)
+/*
+ * gw_db_open: open and lock table for reading (and writing)
+ */
+GW_DB gw_db_open (const char *fname, int write_flag, int block)
{
char file_head_buf[FILE_HEAD_LEN];
GW_DB db;
int r;
- if (!(db = malloc (sizeof(*db))))
- return NULL;
+ db = malloc (sizeof(*db));
+ if (!db)
+ {
+ gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "malloc");
+ exit (1);
+ }
db->dirty = 0;
if (!(db->hash_array = malloc (DB_HASH * sizeof(*db->hash_array))))
- return gw_db_free (db);
+ {
+ gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "malloc");
+ exit (1);
+ }
if (write_flag)
- db->fd = open (fname, O_RDWR|O_CREAT, 0666);
+ {
+ if ((db->fd = open (fname, O_RDWR|O_CREAT, 0666)) == -1)
+ {
+ gw_log (GW_LOG_FATAL|GW_LOG_ERRNO, mod, "open %s", fname);
+ exit (1);
+ }
+ }
else
- db->fd = open (fname, O_RDONLY);
- if (db->fd == -1)
- return gw_db_free (db);
- lock_file (db->fd, write_flag ? F_WRLCK : F_RDLCK);
+ {
+ if ((db->fd = open (fname, O_RDONLY)) == -1)
+ {
+ gw_log (GW_LOG_WARN|GW_LOG_ERRNO, mod, " open %s", fname);
+ return gw_db_free (db);
+ }
+ }
+ if (block)
+ lock_file (db->fd, 1, write_flag ? F_WRLCK : F_RDLCK);
+ else
+ {
+ r = lock_file (db->fd, 0, write_flag ? F_WRLCK : F_RDLCK);
+ if (r == -1)
+ {
+ gw_log (GW_LOG_WARN|GW_LOG_ERRNO, mod, "flock %s", fname);
+ close (db->fd);
+ return gw_db_free (db);
+ }
+ }
r = read (db->fd, file_head_buf, FILE_HEAD_LEN);
if (r == -1)
return gw_db_free (db);
return db;
}
-
+/*
+ * gw_db_close: close table and flush
+ */
int gw_db_close (GW_DB db)
{
int r = 0;
if (db->dirty)
r = write_head (db);
- lock_file (db->fd, F_UNLCK);
+ lock_file (db->fd, 1, F_UNLCK);
if (close (db->fd) == -1)
{
gw_db_free (db);
return r;
}
+/*
+ * gw_db_no_ent: return number of entries in table
+ */
int gw_db_no_ent (GW_DB db)
{
return db->head.no_of_entries;
}
+/*
+ * gw_db_seq_no: return sequence number
+ */
int gw_db_seq_no (GW_DB db)
{
return db->head.sequence_no;
projects / egate.git / blobdiff