source3/lib/dbwrap.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Database interface wrapper
   4    Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2006
   5
   6    Major code contributions from Aleksey Fedoseev (fedoseev@ru.ibm.com)
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "dbwrap.h"
  24 #include "util_tdb.h"
  25 #ifdef CLUSTER_SUPPORT
  26 #include "ctdb_private.h"
  27 #endif
  28 /*
  29  * Fall back using fetch_locked if no genuine fetch operation is provided
  30  */
  31
  32 static int dbwrap_fallback_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
  33                                  TDB_DATA key, TDB_DATA *data)
  34 {
  35         struct db_record *rec;
  36
  37         if (!(rec = db->fetch_locked(db, mem_ctx, key))) {
  38                 return -1;
  39         }
  40
  41         data->dsize = rec->value.dsize;
  42         data->dptr = talloc_move(mem_ctx, &rec->value.dptr);
  43         TALLOC_FREE(rec);
  44         return 0;
  45 }
  46
  47 /*
  48  * Fall back using fetch if no genuine parse operation is provided
  49  */
  50
  51 static int dbwrap_fallback_parse_record(struct db_context *db, TDB_DATA key,
  52                                         int (*parser)(TDB_DATA key,
  53                                                       TDB_DATA data,
  54                                                       void *private_data),
  55                                         void *private_data)
  56 {
  57         TDB_DATA data;
  58         int res;
  59
  60         res = db->fetch(db, talloc_tos(), key, &data);
  61         if (res != 0) {
  62                 return res;
  63         }
  64
  65         res = parser(key, data, private_data);
  66         TALLOC_FREE(data.dptr);
  67         return res;
  68 }
  69
  70 bool db_is_local(const char *name)
  71 {
  72 #ifdef CLUSTER_SUPPORT
  73         const char *sockname = lp_ctdbd_socket();
  74
  75         if(!sockname || !*sockname) {
  76                 sockname = CTDB_PATH;
  77         }
  78
  79         if (lp_clustering() && socket_exist(sockname)) {
  80                 const char *partname;
  81                 /* ctdb only wants the file part of the name */
  82                 partname = strrchr(name, '/');
  83                 if (partname) {
  84                         partname++;
  85                 } else {
  86                         partname = name;
  87                 }
  88                 /* allow ctdb for individual databases to be disabled */
  89                 if (lp_parm_bool(-1, "ctdb", partname, True)) {
  90                         return false;
  91                 }
  92         }
  93 #endif
  94         return true;
  95 }
  96
  97 /**
  98  * open a database
  99  */
 100 struct db_context *db_open(TALLOC_CTX *mem_ctx,
 101                            const char *name,
 102                            int hash_size, int tdb_flags,
 103                            int open_flags, mode_t mode)
 104 {
 105         struct db_context *result = NULL;
 106 #ifdef CLUSTER_SUPPORT
 107         const char *sockname = lp_ctdbd_socket();
 108
 109         if(!sockname || !*sockname) {
 110                 sockname = CTDB_PATH;
 111         }
 112
 113         if (lp_clustering()) {
 114                 const char *partname;
 115
 116                 if (!socket_exist(sockname)) {
 117                         DEBUG(1, ("ctdb socket does not exist - is ctdb not "
 118                                   "running?\n"));
 119                         return NULL;
 120                 }
 121
 122                 /* ctdb only wants the file part of the name */
 123                 partname = strrchr(name, '/');
 124                 if (partname) {
 125                         partname++;
 126                 } else {
 127                         partname = name;
 128                 }
 129                 /* allow ctdb for individual databases to be disabled */
 130                 if (lp_parm_bool(-1, "ctdb", partname, True)) {
 131                         result = db_open_ctdb(mem_ctx, partname, hash_size,
 132                                               tdb_flags, open_flags, mode);
 133                         if (result == NULL) {
 134                                 DEBUG(0,("failed to attach to ctdb %s\n",
 135                                          partname));
 136                                 if (errno == 0) {
 137                                         errno = EIO;
 138                                 }
 139                                 return NULL;
 140                         }
 141                 }
 142         }
 143
 144 #endif
 145
 146         if (result == NULL) {
 147                 result = db_open_tdb(mem_ctx, name, hash_size,
 148                                      tdb_flags, open_flags, mode);
 149         }
 150
 151         if ((result != NULL) && (result->fetch == NULL)) {
 152                 result->fetch = dbwrap_fallback_fetch;
 153         }
 154         if ((result != NULL) && (result->parse_record == NULL)) {
 155                 result->parse_record = dbwrap_fallback_parse_record;
 156         }
 157
 158         return result;
 159 }