env_open.c

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 *	Discard an environment, internal version.
 */
static int
__dbenv_remove_int(dbenv, db_home, flags)
	DB_ENV *dbenv;
	const char *db_home;
	u_int32_t flags;
{
	int ret;

	/* Initialize the DB_ENV structure. */
	if ((ret = __dbenv_config(dbenv, db_home, flags)) != 0)
		return (ret);

	/* Remove the environment. */
	return (__db_e_remove(dbenv, flags));
}

/*
 * __dbenv_config --
 *	Minor initialization of the DB_ENV structure, read the DB_CONFIG file.
 */
static int
__dbenv_config(dbenv, db_home, flags)
	DB_ENV *dbenv;
	const char *db_home;
	u_int32_t flags;
{
	FILE *fp;
	int ret;
	char *p, buf[256];

	/*
	 * Set the database home.  Do this before calling __db_appname,
	 * it uses the home directory.
	 */
	if ((ret = __db_home(dbenv, db_home, flags)) != 0)
		return (ret);

	/* Parse the config file. */
	p = NULL;
	if ((ret =
	    __db_appname(dbenv, DB_APP_NONE, "DB_CONFIG", 0, NULL, &p)) != 0)
		return (ret);
	if (p == NULL)
		fp = NULL;
	else {
		fp = fopen(p, "r");
		__os_free(dbenv, p);
	}

	if (fp != NULL) {
		while (fgets(buf, sizeof(buf), fp) != NULL) {
			if ((p = strchr(buf, '\n')) != NULL)
				*p = '\0';
			else if (strlen(buf) + 1 == sizeof(buf)) {
				__db_err(dbenv, "DB_CONFIG: line too long");
				(void)fclose(fp);
				return (EINVAL);
			}
			if (buf[0] == '\0' ||
			    buf[0] == '#' || isspace((int)buf[0]))
				continue;

			if ((ret = __db_parse(dbenv, buf)) != 0) {
				(void)fclose(fp);
				return (ret);
			}
		}
		(void)fclose(fp);
	}

	/*
	 * If no temporary directory path was specified in the config file,
	 * choose one.
	 */
	if (dbenv->db_tmp_dir == NULL && (ret = __os_tmpdir(dbenv, flags)) != 0)
		return (ret);

	/* Flag that the DB_ENV structure has been initialized. */
	F_SET(dbenv, DB_ENV_OPEN_CALLED);

	return (0);
}

/*
 * __dbenv_close_pp --
 *	DB_ENV->close pre/post processor.
 *
 * PUBLIC: int __dbenv_close_pp __P((DB_ENV *, u_int32_t));
 */
int
__dbenv_close_pp(dbenv, flags)
	DB_ENV *dbenv;
	u_int32_t flags;
{
	int rep_check, ret, t_ret;

	ret = 0;

	PANIC_CHECK(dbenv);

	/*
	 * Validate arguments, but as a DB_ENV handle destructor, we can't
	 * fail.
	 */
	if (flags != 0 &&
	    (t_ret = __db_ferr(dbenv, "DB_ENV->close", 0)) != 0 && ret == 0)
		ret = t_ret;

	rep_check = IS_ENV_REPLICATED(dbenv) ? 1 : 0;
	if (rep_check)
		__env_rep_enter(dbenv);

	if ((t_ret = __dbenv_close(dbenv, rep_check)) != 0 && ret == 0)
		ret = t_ret;

	return (ret);
}

/*
 * __dbenv_close --
 *	DB_ENV->close.
 *
 * PUBLIC: int __dbenv_close __P((DB_ENV *, int));
 */
int
__dbenv_close(dbenv, rep_check)
	DB_ENV *dbenv;
	int rep_check;
{
	int ret, t_ret;
	char **p;

	ret = 0;

	/*
	 * Before checking the reference count, we have to see if we were in
	 * the middle of restoring transactions and need to close the open
	 * files.
	 */
	if (TXN_ON(dbenv) && (t_ret = __txn_preclose(dbenv)) != 0 && ret == 0)
		ret = t_ret;

	if (REP_ON(dbenv) &&
	    (t_ret = __rep_preclose(dbenv, 1)) != 0 && ret == 0)
		ret = t_ret;

	/*
	 * Detach from the regions and undo the allocations done by
	 * DB_ENV->open.
	 */
	if ((t_ret = __dbenv_refresh(dbenv, 0, rep_check)) != 0 && ret == 0)
		ret = t_ret;

	/* Do per-subsystem close. */
	if ((t_ret = __lock_dbenv_close(dbenv)) != 0 && ret == 0)
		ret = t_ret;

	if ((t_ret = __rep_dbenv_close(dbenv)) != 0 && ret == 0)
		ret = t_ret;

#ifdef HAVE_CRYPTO
	/*
	 * Crypto comes last, because higher level close functions need
	 * cryptography.
	 */
	if ((t_ret = __crypto_dbenv_close(dbenv)) != 0 && ret == 0)
		ret = t_ret;
#endif

	/* Release any string-based configuration parameters we've copied. */
	if (dbenv->db_log_dir != NULL)
		__os_free(dbenv, dbenv->db_log_dir);
	if (dbenv->db_tmp_dir != NULL)
		__os_free(dbenv, dbenv->db_tmp_dir);
	if (dbenv->db_data_dir != NULL) {
		for (p = dbenv->db_data_dir; *p != NULL; ++p)
			__os_free(dbenv, *p);
		__os_free(dbenv, dbenv->db_data_dir);
	}

	/* Discard the structure. */
	memset(dbenv, CLEAR_BYTE, sizeof(DB_ENV));
	__os_free(NULL, dbenv);

	return (ret);
}

/*
 * __dbenv_refresh --
 *	Refresh the DB_ENV structure, releasing resources allocated by
 * DB_ENV->open, and returning it to the state it was in just before
 * open was called.  (Note that this means that any state set by
 * pre-open configuration functions must be preserved.)
 */
static int
__dbenv_refresh(dbenv, orig_flags, rep_check)
	DB_ENV *dbenv;
	u_int32_t orig_flags;
	int rep_check;
{
	DB *ldbp;
	DB_MPOOL *dbmp;
	int ret, t_ret;

	dbmp = dbenv->mp_handle;
	ret = 0;

	/*
	 * Refresh subsystems, in the reverse order they were opened (txn
	 * must be first, it may want to discard locks and flush the log).
	 *
	 * !!!
	 * Note that these functions, like all of __dbenv_refresh, only undo
	 * the effects of __dbenv_open.  Functions that undo work done by
	 * db_env_create or by a configuration function should go in
	 * __dbenv_close.
	 */
	if (TXN_ON(dbenv) &&
	    (t_ret = __txn_dbenv_refresh(dbenv)) != 0 && ret == 0)
		ret = t_ret;

	if (LOGGING_ON(dbenv) &&
	    (t_ret = __log_dbenv_refresh(dbenv)) != 0 && ret == 0)
		ret = t_ret;

	/*
	 * Locking should come after logging, because closing log results
	 * in files closing which may require locks being released.
	 */
	if (LOCKING_ON(dbenv)) {
		if (!F_ISSET(dbenv, DB_ENV_THREAD) &&
		    dbenv->env_lid != DB_LOCK_INVALIDID &&
		    (t_ret = __lock_id_free(dbenv, dbenv->env_lid)) != 0 &&
		    ret == 0)
			ret = t_ret;
		dbenv->env_lid = DB_LOCK_INVALIDID;

		if ((t_ret = __lock_dbenv_refresh(dbenv)) != 0 && ret == 0)
			ret = t_ret;
	}

	/*
	 * Discard DB list and its mutex.
	 * Discard the MT mutex.
	 *
	 * !!!
	 * This must be done before we close the mpool region because we
	 * may have allocated the DB handle mutex in the mpool region.
	 * It must be done *after* we close the log region, though, because
	 * we close databases and try to acquire the mutex when we close
	 * log file handles.  Ick.
	 */
	if (dbenv->db_ref != 0) {
		__db_err(dbenv, "Database handles remain at environment close");
		for (ldbp = LIST_FIRST(&dbenv->dblist);
		    ldbp != NULL; ldbp = LIST_NEXT(ldbp, dblistlinks))
			__db_err(dbenv, "Open database handle: %s%s%s",
			    ldbp->fname, ldbp->dname == NULL ? "" : "/",
			    ldbp->dname == NULL ? "" : ldbp->dname);
		if (ret == 0)
			ret = EINVAL;
	}
	LIST_INIT(&dbenv->dblist);
	if (dbenv->dblist_mutexp != NULL)
		__db_mutex_free(dbenv, dbmp->reginfo, dbenv->dblist_mutexp);
	if (dbenv->mt_mutexp != NULL)
		__db_mutex_free(dbenv, dbmp->reginfo, dbenv->mt_mutexp);
	if (dbenv->mt != NULL) {
		__os_free(dbenv, dbenv->mt);
		dbenv->mt = NULL;
	}

	if (MPOOL_ON(dbenv)) {
		/*
		 * If it's a private environment, flush the contents to disk.
		 * Recovery would have put everything back together, but it's
		 * faster and cleaner to flush instead.
		 */
		if (F_ISSET(dbenv, DB_ENV_PRIVATE) &&
		    (t_ret = __memp_sync(dbenv, NULL)) != 0 && ret == 0)
			ret = t_ret;
		if ((t_ret = __memp_dbenv_refresh(dbenv)) != 0 && ret == 0)
			ret = t_ret;
	}

	/*
	 * If we're included in a shared replication handle count, this
	 * is our last chance to decrement that count.
	 *
	 * !!!
	 * We can't afford to do anything dangerous after we decrement the
	 * handle count, of course, as replication may be proceeding with
	 * client recovery.  However, since we're discarding the regions
	 * as soon as we drop the handle count, there's little opportunity
	 * to do harm.
	 */
	if (rep_check)
		__env_db_rep_exit(dbenv);

	/*
	 * Detach from the region.
	 *
	 * Must come after we call __env_db_rep_exit above.
	 */
	__rep_dbenv_refresh(dbenv);

	if (dbenv->reginfo != NULL) {
		if ((t_ret = __db_e_detach(dbenv, 0)) != 0 && ret == 0)
			ret = t_ret;
		/*
		 * !!!
		 * Don't free dbenv->reginfo or set the reference to NULL,
		 * that was done by __db_e_detach().
		 */
	}

	/* Undo changes and allocations done by __dbenv_open. */
	if (dbenv->db_home != NULL) {
		__os_free(dbenv, dbenv->db_home);
		dbenv->db_home = NULL;
	}

	dbenv->open_flags = 0;
	dbenv->db_mode = 0;

	if (dbenv->recover_dtab != NULL) {
		__os_free(dbenv, dbenv->recover_dtab);
		dbenv->recover_dtab = NULL;
		dbenv->recover_dtab_size = 0;
	}

	dbenv->flags = orig_flags;

	return (ret);
}

#define	DB_ADDSTR(add) {						\
	/*								\
	 * The string might be NULL or zero-length, and the p[-1]	\
	 * might indirect to before the beginning of our buffer.	\
	 */								\
	if ((add) != NULL && (add)[0] != '\0') {			\
		/* If leading slash, start over. */			\
		if (__os_abspath(add)) {				\
			p = str;					\
			slash = 0;					\
		}							\
		/* Append to the current string. */			\
		len = strlen(add);					\
		if (slash)						\
			*p++ = PATH_SEPARATOR[0];			\
		memcpy(p, add, len);					\
		p += len;						\
		slash = strchr(PATH_SEPARATOR, p[-1]) == NULL;		\
	}								\
}

/*
 * __dbenv_get_open_flags
 *	Retrieve the flags passed to DB_ENV->open.
 *
 * PUBLIC: int __dbenv_get_open_flags __P((DB_ENV *, u_int32_t *));
 */
int
__dbenv_get_open_flags(dbenv, flagsp)
	DB_ENV *dbenv;
	u_int32_t *flagsp;
{
	ENV_ILLEGAL_BEFORE_OPEN(dbenv, "DB_ENV->get_open_flags");

	*flagsp = dbenv->open_flags;
	return (0);
}

/*
 * __db_appname --
 *	Given an optional DB environment, directory and file name and type
 *	of call, build a path based on the DB_ENV->open rules, and return
 *	it in allocated space.
 *
 * PUBLIC: int __db_appname __P((DB_ENV *, APPNAME,
 * PUBLIC:    const char *, u_int32_t, DB_FH **, char **));
 */
int
__db_appname(dbenv, appname, file, tmp_oflags, fhpp, namep)
	DB_ENV *dbenv;
	APPNAME appname;
	const char *file;
	u_int32_t tmp_oflags;
	DB_FH **fhpp;
	char **namep;
{
	size_t len, str_len;
	int data_entry, ret, slash, tmp_create;
	const char *a, *b;
	char *p, *str;

	a = b = NULL;
	data_entry = -1;
	tmp_create = 0;

	/*
	 * We don't return a name when creating temporary files, just a file
	 * handle.  Default to an error now.
	 */
	if (fhpp != NULL)
		*fhpp = NULL;
	if (namep != NULL)
		*namep = NULL;

	/*
	 * Absolute path names are never modified.  If the file is an absolute
	 * path, we're done.
	 */
	if (file != NULL && __os_abspath(file))
		return (__os_strdup(dbenv, file, namep));

	/* Everything else is relative to the environment home. */
	if (dbenv != NULL)
		a = dbenv->db_home;

retry:	/*
	 * DB_APP_NONE:
	 *      DB_HOME/file
	 * DB_APP_DATA:
	 *      DB_HOME/DB_DATA_DIR/file
	 * DB_APP_LOG:
	 *      DB_HOME/DB_LOG_DIR/file
	 * DB_APP_TMP:
	 *      DB_HOME/DB_TMP_DIR/<create>
	 */
	switch (appname) {
	case DB_APP_NONE:
		break;
	case DB_APP_DATA:
		if (dbenv != NULL && dbenv->db_data_dir != NULL &&
		    (b = dbenv->db_data_dir[++data_entry]) == NULL) {
			data_entry = -1;
			b = dbenv->db_data_dir[0];
		}
		break;
	case DB_APP_LOG:
		if (dbenv != NULL)
			b = dbenv->db_log_dir;
		break;
	case DB_APP_TMP:
		if (dbenv != NULL)
			b = dbenv->db_tmp_dir;
		tmp_create = 1;
		break;
	}

	len =