source3/lib/dbwrap/dbwrap_open.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Database interface wrapper
   4
   5    Copyright (C) Volker Lendecke 2005-2007
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "dbwrap/dbwrap.h"
  23 #include "dbwrap/dbwrap_private.h"
  24 #include "dbwrap/dbwrap_open.h"
  25 #include "dbwrap/dbwrap_tdb.h"
  26 #include "dbwrap/dbwrap_ctdb.h"
  27 #include "lib/param/param.h"
  28 #include "lib/cluster_support.h"
  29 #include "lib/messages_ctdb.h"
  30 #include "util_tdb.h"
  31 #include "ctdbd_conn.h"
  32 #include "messages.h"
  33
  34 bool db_is_local(const char *name)
  35 {
  36         const char *sockname = lp_ctdbd_socket();
  37
  38         if (lp_clustering() && socket_exist(sockname)) {
  39                 const char *partname;
  40                 /* ctdb only wants the file part of the name */
  41                 partname = strrchr(name, '/');
  42                 if (partname) {
  43                         partname++;
  44                 } else {
  45                         partname = name;
  46                 }
  47                 /* allow ctdb for individual databases to be disabled */
  48                 if (lp_parm_bool(-1, "ctdb", partname, True)) {
  49                         return false;
  50                 }
  51         }
  52
  53         return true;
  54 }
  55
  56 /**
  57  * open a database
  58  */
  59 struct db_context *db_open(TALLOC_CTX *mem_ctx,
  60                            const char *name,
  61                            int hash_size, int tdb_flags,
  62                            int open_flags, mode_t mode,
  63                            enum dbwrap_lock_order lock_order,
  64                            uint64_t dbwrap_flags)
  65 {
  66         struct db_context *result = NULL;
  67         const char *base;
  68         const char *sockname;
  69
  70         if (!DBWRAP_LOCK_ORDER_VALID(lock_order)) {
  71                 errno = EINVAL;
  72                 return NULL;
  73         }
  74
  75         base = strrchr_m(name, '/');
  76         if (base != NULL) {
  77                 base++;
  78         } else {
  79                 base = name;
  80         }
  81
  82         if (tdb_flags & TDB_CLEAR_IF_FIRST) {
  83                 bool try_readonly = false;
  84
  85                 if (dbwrap_flags & DBWRAP_FLAG_OPTIMIZE_READONLY_ACCESS) {
  86                         try_readonly = true;
  87                 }
  88
  89                 try_readonly = lp_parm_bool(-1, "dbwrap_optimize_readonly", "*", try_readonly);
  90                 try_readonly = lp_parm_bool(-1, "dbwrap_optimize_readonly", base, try_readonly);
  91
  92                 if (try_readonly) {
  93                         dbwrap_flags |= DBWRAP_FLAG_OPTIMIZE_READONLY_ACCESS;
  94                 } else {
  95                         dbwrap_flags &= ~DBWRAP_FLAG_OPTIMIZE_READONLY_ACCESS;
  96                 }
  97         }
  98
  99         if (tdb_flags & TDB_CLEAR_IF_FIRST) {
 100                 bool try_mutex = true;
 101                 bool require_mutex = false;
 102
 103                 try_mutex = lp_parm_bool(-1, "dbwrap_tdb_mutexes", "*", try_mutex);
 104                 try_mutex = lp_parm_bool(-1, "dbwrap_tdb_mutexes", base, try_mutex);
 105
 106                 if (!lp_use_mmap()) {
 107                         /*
 108                          * Mutexes require mmap. "use mmap = no" can
 109                          * be a debugging tool, so let it override the
 110                          * mutex parameters
 111                          */
 112                         try_mutex = false;
 113                 }
 114
 115                 if (try_mutex && tdb_runtime_check_for_robust_mutexes()) {
 116                         tdb_flags |= TDB_MUTEX_LOCKING;
 117                 }
 118
 119                 require_mutex = lp_parm_bool(-1, "dbwrap_tdb_require_mutexes",
 120                                            "*", require_mutex);
 121                 require_mutex = lp_parm_bool(-1, "dbwrap_tdb_require_mutexes",
 122                                            base, require_mutex);
 123
 124                 if (require_mutex) {
 125                         tdb_flags |= TDB_MUTEX_LOCKING;
 126                 }
 127         }
 128
 129         sockname = lp_ctdbd_socket();
 130
 131         if (lp_clustering()) {
 132                 if (!socket_exist(sockname)) {
 133                         DEBUG(1, ("ctdb socket does not exist - is ctdb not "
 134                                   "running?\n"));
 135                         return NULL;
 136                 }
 137
 138                 /* allow ctdb for individual databases to be disabled */
 139                 if (lp_parm_bool(-1, "ctdb", base, true)) {
 140                         struct messaging_context *msg_ctx;
 141                         struct ctdbd_connection *conn;
 142
 143                         conn = messaging_ctdb_connection();
 144                         if (conn == NULL) {
 145                                 DBG_WARNING("No ctdb connection\n");
 146                                 errno = EIO;
 147                                 return NULL;
 148                         }
 149                         msg_ctx = server_messaging_context();
 150
 151                         result = db_open_ctdb(mem_ctx, msg_ctx, base,
 152                                               hash_size,
 153                                               tdb_flags, open_flags, mode,
 154                                               lock_order, dbwrap_flags);
 155                         if (result == NULL) {
 156                                 DBG_ERR("failed to attach to ctdb %s\n", base);
 157                                 if (errno == 0) {
 158                                         errno = EIO;
 159                                 }
 160                                 return NULL;
 161                         }
 162                 }
 163         }
 164
 165         if (result == NULL) {
 166                 struct loadparm_context *lp_ctx = loadparm_init_s3(mem_ctx, loadparm_s3_helpers());
 167
 168                 if (hash_size == 0) {
 169                         hash_size = lpcfg_tdb_hash_size(lp_ctx, name);
 170                 }
 171                 tdb_flags = lpcfg_tdb_flags(lp_ctx, tdb_flags);
 172
 173                 result = dbwrap_local_open(
 174                         mem_ctx,
 175                         name,
 176                         hash_size,
 177                         tdb_flags,
 178                         open_flags,
 179                         mode,
 180                         lock_order,
 181                         dbwrap_flags);
 182                 talloc_unlink(mem_ctx, lp_ctx);
 183         }
 184         return result;
 185 }