source/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 #ifdef CLUSTER_SUPPORT
  24 #include "ctdb_private.h"
  25 #endif
  26 /*
  27  * Fall back using fetch_locked if no genuine fetch operation is provided
  28  */
  29
  30 static int dbwrap_fallback_fetch(struct db_context *db, TALLOC_CTX *mem_ctx,
  31                                  TDB_DATA key, TDB_DATA *data)
  32 {
  33         struct db_record *rec;
  34
  35         if (!(rec = db->fetch_locked(db, mem_ctx, key))) {
  36                 return -1;
  37         }
  38
  39         data->dsize = rec->value.dsize;
  40         data->dptr = talloc_move(mem_ctx, &rec->value.dptr);
  41         TALLOC_FREE(rec);
  42         return 0;
  43 }
  44
  45 /**
  46  * open a database
  47  */
  48 struct db_context *db_open(TALLOC_CTX *mem_ctx,
  49                            const char *name,
  50                            int hash_size, int tdb_flags,
  51                            int open_flags, mode_t mode)
  52 {
  53         struct db_context *result = NULL;
  54 #ifdef CLUSTER_SUPPORT
  55         const char *sockname = lp_ctdbd_socket();
  56 #endif
  57
  58 #ifdef CLUSTER_SUPPORT
  59         if(!sockname || !*sockname) {
  60                 sockname = CTDB_PATH;
  61         }
  62
  63         if (lp_clustering()) {
  64                 const char *partname;
  65
  66                 if (!socket_exist(sockname)) {
  67                         DEBUG(1, ("ctdb socket does not exist - is ctdb not "
  68                                   "running?\n"));
  69                         return NULL;
  70                 }
  71
  72                 /* ctdb only wants the file part of the name */
  73                 partname = strrchr(name, '/');
  74                 if (partname) {
  75                         partname++;
  76                 } else {
  77                         partname = name;
  78                 }
  79                 /* allow ctdb for individual databases to be disabled */
  80                 if (lp_parm_bool(-1, "ctdb", partname, True)) {
  81                         result = db_open_ctdb(mem_ctx, partname, hash_size,
  82                                               tdb_flags, open_flags, mode);
  83                         if (result == NULL) {
  84                                 DEBUG(0,("failed to attach to ctdb %s\n",
  85                                          partname));
  86                                 if (errno == 0) {
  87                                         errno = EIO;
  88                                 }
  89                                 return NULL;
  90                         }
  91                 }
  92         }
  93
  94 #endif
  95
  96         if (result == NULL) {
  97                 result = db_open_tdb(mem_ctx, name, hash_size,
  98                                      tdb_flags, open_flags, mode);
  99         }
 100
 101         if ((result != NULL) && (result->fetch == NULL)) {
 102                 result->fetch = dbwrap_fallback_fetch;
 103         }
 104
 105         return result;
 106 }
 107
 108 NTSTATUS dbwrap_delete_bystring(struct db_context *db, const char *key)
 109 {
 110         struct db_record *rec;
 111         NTSTATUS status;
 112
 113         rec = db->fetch_locked(db, talloc_tos(), string_term_tdb_data(key));
 114         if (rec == NULL) {
 115                 return NT_STATUS_NO_MEMORY;
 116         }
 117         status = rec->delete_rec(rec);
 118         TALLOC_FREE(rec);
 119         return status;
 120 }
 121
 122 NTSTATUS dbwrap_store_bystring(struct db_context *db, const char *key,
 123                                TDB_DATA data, int flags)
 124 {
 125         struct db_record *rec;
 126         NTSTATUS status;
 127
 128         rec = db->fetch_locked(db, talloc_tos(), string_term_tdb_data(key));
 129         if (rec == NULL) {
 130                 return NT_STATUS_NO_MEMORY;
 131         }
 132
 133         status = rec->store(rec, data, flags);
 134         TALLOC_FREE(rec);
 135         return status;
 136 }
 137
 138 TDB_DATA dbwrap_fetch_bystring(struct db_context *db, TALLOC_CTX *mem_ctx,
 139                                const char *key)
 140 {
 141         TDB_DATA result;
 142
 143         if (db->fetch(db, mem_ctx, string_term_tdb_data(key), &result) == -1) {
 144                 return make_tdb_data(NULL, 0);
 145         }
 146
 147         return result;
 148 }