/* $Cambridge: exim/src/src/lookups/dbmdb.c,v 1.6 2009/11/16 19:50:38 nm4 Exp $ */

/*************************************************
*     Exim - an Internet mail transport agent    *
*************************************************/

/* Copyright (c) University of Cambridge 1995 - 2009 */
/* See the file NOTICE for conditions of use and distribution. */

#include "../exim.h"
#include "lf_functions.h"


/*************************************************
*              Open entry point                  *
*************************************************/

/* See local README for interface description */

static void *
dbmdb_open(uschar *filename, uschar **errmsg)
{
EXIM_DB *yield;
EXIM_DBOPEN(filename, O_RDONLY, 0, &yield);
if (yield == NULL)
  {
  int save_errno = errno;
  *errmsg = string_open_failed(errno, "%s as a %s file", filename, EXIM_DBTYPE);
  errno = save_errno;
  }
return yield;
}



/*************************************************
*             Check entry point                  *
*************************************************/

/* This needs to know more about the underlying files than is good for it!
We need to know what the real file names are in order to check the owners and
modes. If USE_DB is set, we know it is Berkeley DB, which uses an unmodified
file name. If USE_TDB or USE_GDBM is set, we know it is tdb or gdbm, which do
the same. Otherwise, for safety, we have to check for x.db or x.dir and x.pag.
*/

static BOOL
dbmdb_check(void *handle, uschar *filename, int modemask, uid_t *owners,
  gid_t *owngroups, uschar **errmsg)
{
int rc;
handle = handle;    /* Keep picky compilers happy */

#if defined(USE_DB) || defined(USE_TDB) || defined(USE_GDBM)
rc = lf_check_file(-1, filename, S_IFREG, modemask, owners, owngroups,
  "dbm", errmsg);
#else
  {
  uschar filebuffer[256];
  (void)sprintf(CS filebuffer, "%.250s.db", filename);
  rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
    "dbm", errmsg);
  if (rc < 0)        /* stat() failed */
    {
    (void)sprintf(CS filebuffer, "%.250s.dir", filename);
    rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
      "dbm", errmsg);
    if (rc == 0)     /* x.dir was OK */
      {
      (void)sprintf(CS filebuffer, "%.250s.pag", filename);
      rc = lf_check_file(-1, filebuffer, S_IFREG, modemask, owners, owngroups,
        "dbm", errmsg);
      }
    }
  }
#endif

return rc == 0;
}



/*************************************************
*              Find entry point                  *
*************************************************/

/* See local README for interface description. This function adds 1 to
the keylength in order to include the terminating zero. */

static int
dbmdb_find(void *handle, uschar *filename, uschar *keystring, int length,
  uschar **result, uschar **errmsg, BOOL *do_cache)
{
EXIM_DB *d = (EXIM_DB *)handle;
EXIM_DATUM key, data;

filename = filename;    /* Keep picky compilers happy */
errmsg = errmsg;
do_cache = do_cache;

EXIM_DATUM_INIT(key);               /* Some DBM libraries require datums to */
EXIM_DATUM_INIT(data);              /* be cleared before use. */
EXIM_DATUM_DATA(key) = CS keystring;
EXIM_DATUM_SIZE(key) = length + 1;

if (EXIM_DBGET(d, key, data))
  {
  *result = string_copyn(US EXIM_DATUM_DATA(data), EXIM_DATUM_SIZE(data));
  EXIM_DATUM_FREE(data);            /* Some DBM libraries need a free() call */
  return OK;
  }
return FAIL;
}



/*************************************************
*      Find entry point - no zero on key         *
*************************************************/

/* See local README for interface description */

int
static dbmnz_find(void *handle, uschar *filename, uschar *keystring, int length,
  uschar **result, uschar **errmsg, BOOL *do_cache)
{
return dbmdb_find(handle, filename, keystring, length-1, result, errmsg,
  do_cache);
}



/*************************************************
*              Close entry point                 *
*************************************************/

/* See local README for interface description */

void
static dbmdb_close(void *handle)
{
EXIM_DBCLOSE((EXIM_DB *)handle);
}



/*************************************************
*         Version reporting entry point          *
*************************************************/

/* See local README for interface description. */

#include "../version.h"

void
dbm_version_report(FILE *f)
{
#ifdef DYNLOOKUP
fprintf(f, "Library version: DBM: Exim version %s\n", EXIM_VERSION_STR);
#endif
}


lookup_info dbm_lookup_info = {
  US"dbm",                       /* lookup name */
  lookup_absfile,                /* uses absolute file name */
  dbmdb_open,                    /* open function */
  dbmdb_check,                   /* check function */
  dbmdb_find,                    /* find function */
  dbmdb_close,                   /* close function */
  NULL,                          /* no tidy function */
  NULL,                          /* no quoting function */
  dbm_version_report             /* version reporting */
};

lookup_info dbmz_lookup_info = {
  US"dbmnz",                     /* lookup name */
  lookup_absfile,                /* uses absolute file name */
  dbmdb_open,      /* sic */     /* open function */
  dbmdb_check,     /* sic */     /* check function */
  dbmnz_find,                    /* find function */
  dbmdb_close,     /* sic */     /* close function */
  NULL,                          /* no tidy function */
  NULL,                          /* no quoting function */
  NULL                           /* no version reporting (redundant) */
};

#ifdef DYNLOOKUP
#define dbmdb_lookup_module_info _lookup_module_info
#endif

static lookup_info *_lookup_list[] = { &dbm_lookup_info, &dbmz_lookup_info };
lookup_module_info dbmdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 2 };

/* End of lookups/dbmdb.c */
