src/src/lookups/lmdb.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 2016 - 2018 */
   6 /* Copyright (c) The Exim Maintainers 2020 */
   7 /* See the file NOTICE for conditions of use and distribution. */
   8
   9 #include "../exim.h"
  10
  11 #ifdef EXPERIMENTAL_LMDB
  12
  13 #include <lmdb.h>
  14
  15 typedef struct lmdbstrct
  16 {
  17 MDB_txn *txn;
  18 MDB_dbi db_dbi;
  19 } Lmdbstrct;
  20
  21
  22 /*************************************************
  23 *              Open entry point                  *
  24 *************************************************/
  25
  26 static void *
  27 lmdb_open(const uschar * filename, uschar ** errmsg)
  28 {
  29 MDB_env * db_env = NULL;
  30 Lmdbstrct * lmdb_p;
  31 int ret, save_errno;
  32 const uschar * errstr;
  33
  34 lmdb_p = store_get(sizeof(Lmdbstrct), FALSE);
  35 lmdb_p->txn = NULL;
  36
  37 if ((ret = mdb_env_create(&db_env)))
  38   {
  39   errstr = US"create environment";
  40   goto bad;
  41   }
  42
  43 if ((ret = mdb_env_open(db_env, CS filename, MDB_NOSUBDIR|MDB_RDONLY, 0660)))
  44   {
  45   errstr = string_sprintf("open environment with %s", filename);
  46   goto bad;
  47   }
  48
  49 if ((ret = mdb_txn_begin(db_env, NULL, MDB_RDONLY, &lmdb_p->txn)))
  50   {
  51   errstr = US"start transaction";
  52   goto bad;
  53   }
  54
  55 if ((ret = mdb_open(lmdb_p->txn, NULL, 0, &lmdb_p->db_dbi)))
  56   {
  57   errstr = US"open database";
  58   goto bad;
  59   }
  60
  61 return lmdb_p;
  62
  63 bad:
  64   save_errno = errno;
  65   if (lmdb_p->txn) mdb_txn_abort(lmdb_p->txn);
  66   if (db_env) mdb_env_close(db_env);
  67   *errmsg = string_sprintf("LMDB: Unable to %s: %s", errstr,  mdb_strerror(ret));
  68   errno = save_errno;
  69   return NULL;
  70 }
  71
  72
  73 /*************************************************
  74 *              Find entry point                  *
  75 *************************************************/
  76
  77 static int
  78 lmdb_find(void * handle, const uschar * filename,
  79     const uschar * keystring, int length, uschar ** result, uschar ** errmsg,
  80     uint * do_cache, const uschar * opts)
  81 {
  82 int ret;
  83 MDB_val dbkey, data;
  84 Lmdbstrct * lmdb_p = handle;
  85
  86 dbkey.mv_data = CS keystring;
  87 dbkey.mv_size = length;
  88
  89 DEBUG(D_lookup) debug_printf_indent("LMDB: lookup key: %s\n", CS keystring);
  90
  91 if ((ret = mdb_get(lmdb_p->txn, lmdb_p->db_dbi, &dbkey, &data)) == 0)
  92   {
  93   *result = string_copyn(US data.mv_data, data.mv_size);
  94   DEBUG(D_lookup) debug_printf_indent("LMDB: lookup result: %s\n", *result);
  95   return OK;
  96   }
  97 else if (ret == MDB_NOTFOUND)
  98   {
  99   *errmsg = US"LMDB: lookup, no data found";
 100   DEBUG(D_lookup) debug_printf_indent("%s\n", *errmsg);
 101   return FAIL;
 102   }
 103 else
 104   {
 105   *errmsg = string_sprintf("LMDB: lookup error: %s", mdb_strerror(ret));
 106   DEBUG(D_lookup) debug_printf_indent("%s\n", *errmsg);
 107   return DEFER;
 108   }
 109 }
 110
 111
 112 /*************************************************
 113 *              Close entry point                 *
 114 *************************************************/
 115
 116 static void
 117 lmdb_close(void * handle)
 118 {
 119 Lmdbstrct * lmdb_p = handle;
 120 MDB_env * db_env = mdb_txn_env(lmdb_p->txn);
 121 mdb_txn_abort(lmdb_p->txn);
 122 mdb_env_close(db_env);
 123 }
 124
 125
 126 /*************************************************
 127 *         Version reporting entry point          *
 128 *************************************************/
 129
 130 #include "../version.h"
 131
 132 void
 133 lmdb_version_report(FILE * f)
 134 {
 135 fprintf(f, "Library version: LMDB: Compile: %d.%d.%d\n",
 136     MDB_VERSION_MAJOR, MDB_VERSION_MINOR, MDB_VERSION_PATCH);
 137 #ifdef DYNLOOKUP
 138 fprintf(f, "                        Exim version %s\n", EXIM_VERSION_STR);
 139 #endif
 140 }
 141
 142 static lookup_info lmdb_lookup_info = {
 143   .name = US"lmdb",                     /* lookup name */
 144   .type = lookup_absfile,               /* query-style lookup */
 145   .open = lmdb_open,                    /* open function */
 146   .check = NULL,                        /* no check function */
 147   .find = lmdb_find,                    /* find function */
 148   .close = lmdb_close,                  /* close function */
 149   .tidy = NULL,                         /* tidy function */
 150   .quote = NULL,                        /* quoting function */
 151   .version_report = lmdb_version_report           /* version reporting */
 152 };
 153
 154 #ifdef DYNLOOKUP
 155 # define lmdb_lookup_module_info _lookup_module_info
 156 #endif /* DYNLOOKUP */
 157
 158 static lookup_info *_lookup_list[] = { &lmdb_lookup_info };
 159 lookup_module_info lmdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
 160
 161 #endif /* EXPERIMENTAL_LMDB */