src/lookups/lmdb.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 2016 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 #include "../exim.h"
   9
  10 #ifdef EXPERIMENTAL_LMDB
  11
  12 #include <lmdb.h>
  13
  14 typedef struct lmdbstrct
  15 {
  16 MDB_txn *txn;
  17 MDB_dbi db_dbi;
  18 } Lmdbstrct;
  19
  20
  21 /*************************************************
  22 *              Open entry point                  *
  23 *************************************************/
  24
  25 static void *
  26 lmdb_open(uschar * filename, uschar ** errmsg)
  27 {
  28 MDB_env * db_env = NULL;
  29 Lmdbstrct * lmdb_p;
  30 int ret, save_errno;
  31 const uschar * errstr;
  32
  33 lmdb_p = store_get(sizeof(Lmdbstrct));
  34 lmdb_p->txn = NULL;
  35
  36 if ((ret = mdb_env_create(&db_env)))
  37   {
  38   errstr = US"create environment";
  39   goto bad;
  40   }
  41
  42 if ((ret = mdb_env_open(db_env, CS filename, MDB_NOSUBDIR|MDB_RDONLY, 0660)))
  43   {
  44   errstr = string_sprintf("open environment with %s", filename);
  45   goto bad;
  46   }
  47
  48 if ((ret = mdb_txn_begin(db_env, NULL, MDB_RDONLY, &lmdb_p->txn)))
  49   {
  50   errstr = US"start transaction";
  51   goto bad;
  52   }
  53
  54 if ((ret = mdb_open(lmdb_p->txn, NULL, 0, &lmdb_p->db_dbi)))
  55   {
  56   errstr = US"open database";
  57   goto bad;
  58   }
  59
  60 return lmdb_p;
  61
  62 bad:
  63   save_errno = errno;
  64   if (lmdb_p->txn) mdb_txn_abort(lmdb_p->txn);
  65   if (db_env) mdb_env_close(db_env);
  66   *errmsg = string_sprintf("LMDB: Unable to %s: %s", errstr,  mdb_strerror(ret));
  67   errno = save_errno;
  68   return NULL;
  69 }
  70
  71
  72 /*************************************************
  73 *              Find entry point                  *
  74 *************************************************/
  75
  76 static int
  77 lmdb_find(void * handle, uschar * filename,
  78     const uschar * keystring, int length, uschar ** result, uschar ** errmsg,
  79     uint * do_cache)
  80 {
  81 int ret;
  82 MDB_val dbkey, data;
  83 Lmdbstrct * lmdb_p = handle;
  84
  85 dbkey.mv_data = CS keystring;
  86 dbkey.mv_size = length;
  87
  88 DEBUG(D_lookup) debug_printf("LMDB: lookup key: %s\n", (char *)keystring);
  89
  90 if ((ret = mdb_get(lmdb_p->txn, lmdb_p->db_dbi, &dbkey, &data)) == 0)
  91   {
  92   *result = string_copyn(US data.mv_data, data.mv_size);
  93   DEBUG(D_lookup) debug_printf("LMDB: lookup result: %s\n", *result);
  94   return OK;
  95   }
  96 else if (ret == MDB_NOTFOUND)
  97   {
  98   *errmsg = US"LMDB: lookup, no data found";
  99   DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
 100   return FAIL;
 101   }
 102 else
 103   {
 104   *errmsg = string_sprintf("LMDB: lookup error: %s", mdb_strerror(ret));
 105   DEBUG(D_lookup) debug_printf("%s\n", *errmsg);
 106   return DEFER;
 107   }
 108 }
 109
 110
 111 /*************************************************
 112 *              Close entry point                 *
 113 *************************************************/
 114
 115 static void
 116 lmdb_close(void * handle)
 117 {
 118 Lmdbstrct * lmdb_p = handle;
 119 MDB_env * db_env = mdb_txn_env(lmdb_p->txn);
 120 mdb_txn_abort(lmdb_p->txn);
 121 mdb_env_close(db_env);
 122 }
 123
 124
 125 /*************************************************
 126 *         Version reporting entry point          *
 127 *************************************************/
 128
 129 #include "../version.h"
 130
 131 void
 132 lmdb_version_report(FILE * f)
 133 {
 134 fprintf(f, "Library version: LMDB: Compile: %d.%d.%d\n",
 135     MDB_VERSION_MAJOR, MDB_VERSION_MINOR, MDB_VERSION_PATCH);
 136 #ifdef DYNLOOKUP
 137 fprintf(f, "                        Exim version %s\n", EXIM_VERSION_STR);
 138 #endif
 139 }
 140
 141 static lookup_info lmdb_lookup_info = {
 142   US"lmdb",                     /* lookup name */
 143   lookup_absfile,               /* query-style lookup */
 144   lmdb_open,                    /* open function */
 145   NULL,                         /* no check function */
 146   lmdb_find,                    /* find function */
 147   lmdb_close,                   /* close function */
 148   NULL,                         /* tidy function */
 149   NULL,                         /* quoting function */
 150   lmdb_version_report           /* version reporting */
 151 };
 152
 153 #ifdef DYNLOOKUP
 154 # define lmdb_lookup_module_info _lookup_module_info
 155 #endif /* DYNLOOKUP */
 156
 157 static lookup_info *_lookup_list[] = { &lmdb_lookup_info };
 158 lookup_module_info lmdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
 159
 160 #endif /* EXPERIMENTAL_LMDB */