text: /* Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #include "apr_strings.h"
  #define APR_WANT_MEMFUNC
  #include "apr_want.h"
  
  #define APU_WANT_DB
  #include "apu_want.h"
  
  #if APR_HAVE_STDLIB_H
  #include <stdlib.h> /* for abort() */
  #endif
  
  #include "apu.h"
  
  #if APU_HAVE_DB 
  #include "apr_dbm_private.h"
  
  /*
   * We pick up all varieties of Berkeley DB through db.h (included through
   * apu_select_dbm.h). This code has been compiled/tested against DB1,
   * DB_185, DB2, DB3, and DB4.
   */
  
  #if   defined(DB_VERSION_MAJOR) && (DB_VERSION_MAJOR == 4)
  /* We will treat anything greater than 4.1 as DB4.
   * We can treat 4.0 as DB3.
   */
  #if   defined(DB_VERSION_MINOR) && (DB_VERSION_MINOR >= 1)
  #define DB_VER 4
  #else
  #define DB_VER 3
  #endif
  #elif defined(DB_VERSION_MAJOR) && (DB_VERSION_MAJOR == 3)
  #define DB_VER 3
  #elif defined(DB_VERSION_MAJOR) && (DB_VERSION_MAJOR == 2)
  #define DB_VER 2
  #else
  #define DB_VER 1
  #endif
  
  typedef struct {
      DB *bdb;
  #if DB_VER != 1
      DBC *curs;
  #endif
  } real_file_t;
  
  
  #if DB_VER == 1
  #define TXN_ARG
  #else
  #define TXN_ARG NULL,
  #endif
  
  #define GET_BDB(f)      (((real_file_t *)(f))->bdb)
  
  #define do_fetch(bdb, k, v)     ((*(bdb)->get)(bdb, TXN_ARG &(k), &(v), 0))
  
  #if DB_VER == 1
  #include <sys/fcntl.h>
  #define APR_DBM_DBMODE_RO       O_RDONLY
  #define APR_DBM_DBMODE_RW       O_RDWR
  #define APR_DBM_DBMODE_RWCREATE (O_CREAT | O_RDWR)
  #define APR_DBM_DBMODE_RWTRUNC  (O_CREAT | O_RDWR | O_TRUNC)
  #else
  #define APR_DBM_DBMODE_RO       DB_RDONLY
  #define APR_DBM_DBMODE_RW       0
  #define APR_DBM_DBMODE_RWCREATE DB_CREATE
  #define APR_DBM_DBMODE_RWTRUNC  DB_TRUNCATE
  #endif /* DBVER == 1 */
  
  /* --------------------------------------------------------------------------
  **
  ** UTILITY FUNCTIONS
  */
  
  /* map a DB error to an apr_status_t */
  static apr_status_t db2s(int dberr)
  {
      if (dberr != 0) {
          /* ### need to fix this */
          return APR_OS_START_USEERR + dberr;
      }
  
      return APR_SUCCESS;
  }
  
  
  static apr_status_t set_error(apr_dbm_t *dbm, apr_status_t dbm_said)
  {
      apr_status_t rv = APR_SUCCESS;
  
      /* ### ignore whatever the DBM said (dbm_said); ask it explicitly */
  
      if (dbm_said == APR_SUCCESS) {
          dbm->errcode = 0;
          dbm->errmsg = NULL;
      }
      else {
          /* ### need to fix. dberr was tossed in db2s(). */
          /* ### use db_strerror() */
          dbm->errcode = dbm_said;
  #if DB_VER == 1 || DB_VER == 2
          dbm->errmsg = NULL;
  #else
          dbm->errmsg = db_strerror(dbm_said - APR_OS_START_USEERR);
  #endif
          rv = dbm_said;
      }
  
      return rv;
  }
  
  /* --------------------------------------------------------------------------
  **
  ** DEFINE THE VTABLE FUNCTIONS FOR BERKELEY DB
  **
  ** ### we may need three sets of these: db1, db2, db3
  */
  
  static apr_status_t vt_db_open(apr_dbm_t **pdb, const char *pathname,
                                 apr_int32_t mode, apr_fileperms_t perm,
                                 apr_pool_t *pool)
  {
      real_file_t file;
      int dbmode;
  
      *pdb = NULL;
  
      switch (mode) {
      case APR_DBM_READONLY:
          dbmode = APR_DBM_DBMODE_RO;
          break;
      case APR_DBM_READWRITE:
          dbmode = APR_DBM_DBMODE_RW;
          break;
      case APR_DBM_RWCREATE:
          dbmode = APR_DBM_DBMODE_RWCREATE;
          break;
      case APR_DBM_RWTRUNC:
          dbmode = APR_DBM_DBMODE_RWTRUNC;
          break;
      default:
          return APR_EINVAL;
      }
  
      {
          int dberr;
  
  #if DB_VER >= 3
          if ((dberr = db_create(&file.bdb, NULL, 0)) == 0) {
              if ((dberr = (*file.bdb->open)(file.bdb,
  #if DB_VER == 4
                                             NULL,
  #endif
                                             pathname, NULL, 
                                             DB_HASH, dbmode, 
                                             apr_posix_perms2mode(perm))) != 0) {
                  /* close the DB handler */
                  (void) (*file.bdb->close)(file.bdb, 0);
              }
          }
          file.curs = NULL;
  #elif DB_VER == 2
          dberr = db_open(pathname, DB_HASH, dbmode, apr_posix_perms2mode(perm),
                          NULL, NULL, &file.bdb);
          file.curs = NULL;
  #else
          file.bdb = dbopen(pathname, dbmode, apr_posix_perms2mode(perm),
                            DB_HASH, NULL);
          if (file.bdb == NULL)
              return APR_EGENERAL;      /* ### need a better error */
          dberr = 0;
  #endif
          if (dberr != 0)
              return db2s(dberr);
      }
  
      /* we have an open database... return it */
      *pdb = apr_pcalloc(pool, sizeof(**pdb));
      (*pdb)->pool = pool;
      (*pdb)->type = &apr_dbm_type_db;
      (*pdb)->file = apr_pmemdup(pool, &file, sizeof(file));
  
      /* ### register a cleanup to close the DBM? */
  
      return APR_SUCCESS;
  }
  
  static void vt_db_close(apr_dbm_t *dbm)
  {
      (*GET_BDB(dbm->file)->close)(GET_BDB(dbm->file)
  #if DB_VER != 1
                                   , 0
  #endif
          );
  }
  
  static apr_status_t vt_db_fetch(apr_dbm_t *dbm, apr_datum_t key,
                                  apr_datum_t * pvalue)
  {
      DBT ckey = { 0 };
      DBT rd = { 0 };
      int dberr;
  
      ckey.data = key.dptr;
      ckey.size = key.dsize;
  
      dberr = do_fetch(GET_BDB(dbm->file), ckey, rd);
  
      /* "not found" is not an error. return zero'd value. */
      if (dberr ==
  #if DB_VER == 1
          RET_SPECIAL
  #else
          DB_NOTFOUND
  #endif
          ) {
          memset(&rd, 0, sizeof(rd));
          dberr = 0;
      }
  
      pvalue->dptr = rd.data;
      pvalue->dsize = rd.size;
  
      /* store the error info into DBM, and return a status code. Also, note
         that *pvalue should have been cleared on error. */
      return set_error(dbm, db2s(dberr));
  }
  
  static apr_status_t vt_db_store(apr_dbm_t *dbm, apr_datum_t key,
                                  apr_datum_t value)
  {
      apr_status_t rv;
      DBT ckey = { 0 };
      DBT cvalue = { 0 };
  
      ckey.data = key.dptr;
      ckey.size = key.dsize;
  
      cvalue.data = value.dptr;
      cvalue.size = value.dsize;
  
      rv = db2s((*GET_BDB(dbm->file)->put)(GET_BDB(dbm->file),
                                           TXN_ARG
                                           &ckey,
                                           &cvalue,
                                           0));
  
      /* store any error info into DBM, and return a status code. */
      return set_error(dbm, rv);
  }
  
  static apr_status_t vt_db_del(apr_dbm_t *dbm, apr_datum_t key)
  {
      apr_status_t rv;
      DBT ckey = { 0 };
  
      ckey.data = key.dptr;
      ckey.size = key.dsize;
  
      rv = db2s((*GET_BDB(dbm->file)->del)(GET_BDB(dbm->file),
                                           TXN_ARG
                                           &ckey,
                                           0));
  
      /* store any error info into DBM, and return a status code. */
      return set_error(dbm, rv);
  }
  
  static int vt_db_exists(apr_dbm_t *dbm, apr_datum_t key)
  {
      DBT ckey = { 0 };   /* converted key */
      DBT data = { 0 };
      int dberr;
  
      ckey.data = key.dptr;
      ckey.size = key.dsize;
  
      dberr = do_fetch(GET_BDB(dbm->file), ckey, data);
  
      /* note: the result data is "loaned" to us; we don't need to free it */
  
      /* DB returns DB_NOTFOUND if it doesn't exist. but we want to say
         that *any* error means it doesn't exist. */
      return dberr == 0;
  }
  
  static apr_status_t vt_db_firstkey(apr_dbm_t *dbm, apr_datum_t * pkey)
  {
      real_file_t *f = dbm->file;
      DBT first = { 0 };
      DBT data = { 0 };
      int dberr;
  
  #if DB_VER == 1
      dberr = (*f->bdb->seq)(f->bdb, &first, &data, R_FIRST);
  #else
      if ((dberr = (*f->bdb->cursor)(f->bdb, NULL, &f->curs
  #if DB_VER >= 3 || ((DB_VERSION_MAJOR == 2) && (DB_VERSION_MINOR > 5))
                                     , 0
  #endif
               )) == 0) {
          dberr = (*f->curs->c_get)(f->curs, &first, &data, DB_FIRST);
          if (dberr == DB_NOTFOUND) {
              memset(&first, 0, sizeof(first));
              (*f->curs->c_close)(f->curs);
              f->curs = NULL;
              dberr = 0;
          }
      }
  #endif
  
      pkey->dptr = first.data;
      pkey->dsize = first.size;
  
      /* store any error info into DBM, and return a status code. */
      return set_error(dbm, db2s(dberr));
  }
  
  static apr_status_t vt_db_nextkey(apr_dbm_t *dbm, apr_datum_t * pkey)
  {
      real_file_t *f = dbm->file;
      DBT ckey = { 0 };
      DBT data = { 0 };
      int dberr;
  
      ckey.data = pkey->dptr;
      ckey.size = pkey->dsize;
  
  #if DB_VER == 1
      dberr = (*f->bdb->seq)(f->bdb, &ckey, &data, R_NEXT);
      if (dberr == RET_SPECIAL) {
          dberr = 0;
          ckey.data = NULL;
          ckey.size = 0;
      }
  #else
      if (f->curs == NULL)
          return APR_EINVAL;
  
      dberr = (*f->curs->c_get)(f->curs, &ckey, &data, DB_NEXT);
      if (dberr == DB_NOTFOUND) {
          (*f->curs->c_close)(f->curs);
          f->curs = NULL;
          dberr = 0;
          ckey.data = NULL;
          ckey.size = 0;
      }
  #endif
  
      pkey->dptr = ckey.data;
      pkey->dsize = ckey.size;
  
      /* store any error info into DBM, and return a status code. */
      /* ### or use db2s(dberr) instead of APR_SUCCESS? */
      return set_error(dbm, APR_SUCCESS);
  }
  
  static void vt_db_freedatum(apr_dbm_t *dbm, apr_datum_t data)
  {
      /* nothing to do */
  }
  
  static void vt_db_usednames(apr_pool_t *pool, const char *pathname,
                              const char **used1, const char **used2)
  {
      *used1 = apr_pstrdup(pool, pathname);
      *used2 = NULL;
  }
  
  
  APU_DECLARE_DATA const apr_dbm_type_t apr_dbm_type_db = {
      "db",
  
      vt_db_open,
      vt_db_close,
      vt_db_fetch,
      vt_db_store,
      vt_db_del,
      vt_db_exists,
      vt_db_firstkey,
      vt_db_nextkey,
      vt_db_freedatum,
      vt_db_usednames
  };
  
  #endif /* APU_HAVE_DB */
  