Import BSDDB 4.7.25 (as of svn r89086)

lock/lock_timer.c

@@ -0,0 +1,174 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996,2008 Oracle.  All rights reserved.
+ *
+ * $Id: lock_timer.c 63573 2008-05-23 21:43:21Z trent.nelson $
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+#include "dbinc/lock.h"
+
+/*
+ * __lock_set_timeout --
+ *	Set timeout values in shared memory.
+ *
+ * This is called from the transaction system.  We either set the time that
+ * this transaction expires or the amount of time a lock for this transaction
+ * is permitted to wait.
+ *
+ * PUBLIC: int __lock_set_timeout __P((ENV *,
+ * PUBLIC:      DB_LOCKER *, db_timeout_t, u_int32_t));
+ */
+int
+__lock_set_timeout(env, locker, timeout, op)
+	ENV *env;
+	DB_LOCKER *locker;
+	db_timeout_t timeout;
+	u_int32_t op;
+{
+	int ret;
+
+	if (locker == NULL)
+		return (0);
+	LOCK_REGION_LOCK(env);
+	ret = __lock_set_timeout_internal(env, locker, timeout, op);
+	LOCK_REGION_UNLOCK(env);
+	return (ret);
+}
+
+/*
+ * __lock_set_timeout_internal
+ *		-- set timeout values in shared memory.
+ *
+ * This is the internal version called from the lock system.  We either set
+ * the time that this transaction expires or the amount of time that a lock
+ * for this transaction is permitted to wait.
+ *
+ * PUBLIC: int __lock_set_timeout_internal
+ * PUBLIC:     __P((ENV *, DB_LOCKER *, db_timeout_t, u_int32_t));
+ */
+int
+__lock_set_timeout_internal(env, sh_locker, timeout, op)
+	ENV *env;
+	DB_LOCKER *sh_locker;
+	db_timeout_t timeout;
+	u_int32_t op;
+{
+	DB_LOCKREGION *region;
+	region = env->lk_handle->reginfo.primary;
+
+	if (op == DB_SET_TXN_TIMEOUT) {
+		if (timeout == 0)
+			timespecclear(&sh_locker->tx_expire);
+		else
+			__lock_expires(env, &sh_locker->tx_expire, timeout);
+	} else if (op == DB_SET_LOCK_TIMEOUT) {
+		sh_locker->lk_timeout = timeout;
+		F_SET(sh_locker, DB_LOCKER_TIMEOUT);
+	} else if (op == DB_SET_TXN_NOW) {
+		timespecclear(&sh_locker->tx_expire);
+		__lock_expires(env, &sh_locker->tx_expire, 0);
+		sh_locker->lk_expire = sh_locker->tx_expire;
+		if (!timespecisset(&region->next_timeout) ||
+		    timespeccmp(
+			&region->next_timeout, &sh_locker->lk_expire, >))
+			region->next_timeout = sh_locker->lk_expire;
+	} else
+		return (EINVAL);
+
+	return (0);
+}
+
+/*
+ * __lock_inherit_timeout
+ *		-- inherit timeout values from parent locker.
+ * This is called from the transaction system.  This will
+ * return EINVAL if the parent does not exist or did not
+ * have a current txn timeout set.
+ *
+ * PUBLIC: int __lock_inherit_timeout __P((ENV *, DB_LOCKER *, DB_LOCKER *));
+ */
+int
+__lock_inherit_timeout(env, parent, locker)
+	ENV *env;
+	DB_LOCKER *parent, *locker;
+{
+	int ret;
+
+	ret = 0;
+	LOCK_REGION_LOCK(env);
+
+	/*
+	 * If the parent is not there yet, thats ok.  If it
+	 * does not have any timouts set, then avoid creating
+	 * the child locker at this point.
+	 */
+	if (parent == NULL ||
+	    (timespecisset(&parent->tx_expire) &&
+	    !F_ISSET(parent, DB_LOCKER_TIMEOUT))) {
+		ret = EINVAL;
+		goto err;
+	}
+
+	locker->tx_expire = parent->tx_expire;
+
+	if (F_ISSET(parent, DB_LOCKER_TIMEOUT)) {
+		locker->lk_timeout = parent->lk_timeout;
+		F_SET(locker, DB_LOCKER_TIMEOUT);
+		if (!timespecisset(&parent->tx_expire))
+			ret = EINVAL;
+	}
+
+err:	LOCK_REGION_UNLOCK(env);
+	return (ret);
+}
+
+/*
+ * __lock_expires --
+ *	Set the expire time given the time to live.
+ *
+ * PUBLIC: void __lock_expires __P((ENV *, db_timespec *, db_timeout_t));
+ */
+void
+__lock_expires(env, timespecp, timeout)
+	ENV *env;
+	db_timespec *timespecp;
+	db_timeout_t timeout;
+{
+	db_timespec v;
+
+	/*
+	 * If timespecp is set then it contains "now".  This avoids repeated
+	 * system calls to get the time.
+	 */
+	if (!timespecisset(timespecp))
+		__os_gettime(env, timespecp, 1);
+
+	/* Convert the microsecond timeout argument to a timespec. */
+	DB_TIMEOUT_TO_TIMESPEC(timeout, &v);
+
+	/* Add the timeout to "now". */
+	timespecadd(timespecp, &v);
+}
+
+/*
+ * __lock_expired -- determine if a lock has expired.
+ *
+ * PUBLIC: int __lock_expired __P((ENV *, db_timespec *, db_timespec *));
+ */
+int
+__lock_expired(env, now, timespecp)
+	ENV *env;
+	db_timespec *now, *timespecp;
+{
+	if (!timespecisset(timespecp))
+		return (0);
+
+	if (!timespecisset(now))
+		__os_gettime(env, now, 1);
+
+	return (timespeccmp(now, timespecp, >=));
+}