X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=util%2Fgw-db.c;h=6ee26ee84ad679ee1ecaceb8843d305cfb548fb2;hb=25db261b6bbbfcc7bc26f679f195b51d31b9d7d7;hp=5bbe23fc5a3bb6d03154cf8cbdf854727b561d4b;hpb=ad67147ba5d2e4287bacfcbdaac2e5d9058cb400;p=egate.git diff --git a/util/gw-db.c b/util/gw-db.c index 5bbe23f..6ee26ee 100644 --- a/util/gw-db.c +++ b/util/gw-db.c @@ -1,8 +1,65 @@ +/* + * 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). * @@ -15,29 +72,35 @@ #include #include +#include #include #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]; @@ -55,30 +118,40 @@ static int write_head (GW_DB db) 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; @@ -149,13 +222,16 @@ int gw_db_lookup (GW_DB db, const char *name, int name_length, 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; @@ -210,6 +286,9 @@ int gw_db_insert (GW_DB db, const char *name, int name_length, return 0; } +/* + * gw_db_free: release memory associated with table + */ static GW_DB gw_db_free (GW_DB db) { free (db->hash_array); @@ -217,24 +296,55 @@ static GW_DB gw_db_free (GW_DB db) 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); @@ -261,14 +371,16 @@ GW_DB gw_db_open (const char *fname, int write_flag) 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); @@ -278,11 +390,17 @@ int gw_db_close (GW_DB 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;