-/* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Nicira, Inc.
+/* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2019 Nicira, Inc.
* Copyright (C) 2016 Hewlett Packard Enterprise Development LP
*
* Licensed under the Apache License, Version 2.0 (the "License");
const struct ovsdb_idl_class *,
bool monitor_everything_by_default,
bool retry);
-void ovsdb_idl_set_remote(struct ovsdb_idl *, const char *, bool);
+struct ovsdb_idl *ovsdb_idl_create_unconnected(
+ const struct ovsdb_idl_class *, bool monitor_everything_by_default);
+void ovsdb_idl_set_remote(struct ovsdb_idl *, const char *remote, bool retry);
+void ovsdb_idl_set_shuffle_remotes(struct ovsdb_idl *, bool shuffle);
+void ovsdb_idl_reset_min_index(struct ovsdb_idl *);
void ovsdb_idl_destroy(struct ovsdb_idl *);
void ovsdb_idl_set_leader_only(struct ovsdb_idl *, bool leader_only);
bool ovsdb_idl_has_lock(const struct ovsdb_idl *);
bool ovsdb_idl_is_lock_contended(const struct ovsdb_idl *);
-const struct uuid * ovsdb_idl_get_monitor_id(const struct ovsdb_idl *);
unsigned int ovsdb_idl_get_seqno(const struct ovsdb_idl *);
bool ovsdb_idl_has_ever_connected(const struct ovsdb_idl *);
void ovsdb_idl_enable_reconnect(struct ovsdb_idl *);
void ovsdb_idl_verify_write_only(struct ovsdb_idl *);
bool ovsdb_idl_is_alive(const struct ovsdb_idl *);
+bool ovsdb_idl_is_connected(const struct ovsdb_idl *idl);
int ovsdb_idl_get_last_error(const struct ovsdb_idl *);
void ovsdb_idl_set_probe_interval(const struct ovsdb_idl *, int probe_interval);
const struct ovsdb_idl_table_class *ovsdb_idl_table_class_from_column(
const struct ovsdb_idl_class *, const struct ovsdb_idl_column *);
\f
-/* Choosing columns and tables to replicate. */
+/* Choosing columns and tables to replicate.
+ *
+ * The client may choose any subset of the columns and tables to replicate,
+ * specifying it one of two ways:
+ *
+ * - As a deny list (adding the columns or tables to replicate). To do so,
+ * the client passes false as 'monitor_everything_by_default' to
+ * ovsdb_idl_create() and then calls ovsdb_idl_add_column() and
+ * ovsdb_idl_add_table() for the desired columns and, if necessary, tables.
+ *
+ * - As an allow list (replicating all columns and tables except those
+ * explicitly removed). To do so, the client passes true as
+ * 'monitor_everything_by_default' to ovsdb_idl_create() and then calls
+ * ovsdb_idl_omit() to remove columns.
+ *
+ * There are multiple modes a column may be replicated:
+ *
+ * - Read-only. This is the default. Whenever the column changes in any
+ * replicated row, the value returned by ovsdb_idl_get_seqno() will change,
+ * letting the client know to look at the replicated data again.
+ *
+ * - Write-only. This is for columns that the client sets and updates but
+ * does not want to be alerted about its own updates (which, at the OVSDB
+ * level, cannot be distinguished from updates made by any other client).
+ * The column will be replicated in the same way as for read-only columns,
+ * but the value returned by ovsdb_idl_get_seqno() will not change when the
+ * column changes, saving wasted CPU time.
+ *
+ * (A "write-only" client probably does read the column so that it can know
+ * whether it needs to update it, but it doesn't expect to react to changes
+ * by other clients.)
+ *
+ * To mark a replicated column as write-only, a client calls
+ * ovsdb_idl_omit_alert(). (The column must already be replicated one of
+ * the ways described in the previous list.)
+ *
+ * This is an optimization only and does not affect behavioral correctness
+ * of an otherwise well-written client.
+ *
+ * - Read/write. In theory, an OVSDB client might both read and write a
+ * column, although OVSDB schemas are usually designed so that any given
+ * client only does one or the other. This is actually the same as
+ * read/write columns; that is, the client need take no special action.
+ */
-/* Modes with which the IDL can monitor a column.
+/* Modes with which the IDL can replicate a column. See above comment for
+ * overview.
*
- * If no bits are set, the column is not monitored at all. Its value will
- * always appear to the client to be the default value for its type.
+ * If no bits are set, the IDL does not replicate the column at all. The
+ * client will always see it with the default value for its type.
*
- * If OVSDB_IDL_MONITOR is set, then the column is replicated. Its value will
- * reflect the value in the database. If OVSDB_IDL_ALERT is also set, then the
- * value returned by ovsdb_idl_get_seqno() will change when the column's value
- * changes.
+ * If OVSDB_IDL_MONITOR is set, then the IDL replicates the column and sets it
+ * to to the value in the database. If OVSDB_IDL_ALERT is also set, then the
+ * IDL will change the value returned by ovsdb_idl_get_seqno() when the
+ * column's value changes in any row.
*
* The possible mode combinations are:
*
- * - 0, for a column that a client doesn't care about.
+ * - 0, for a column that a client doesn't care about. This is the default
+ * for every column in every table, if the client passes false for
+ * 'monitor_everything_by_default' to ovsdb_idl_create().
*
* - (OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT), for a column that a client wants
- * to track and possibly update.
+ * to track and possibly update. This is the default for every column in
+ * every table, if the client passes true for
+ * 'monitor_everything_by_default' to ovsdb_idl_create().
*
* - OVSDB_IDL_MONITOR, for columns that a client treats as "write-only",
* that is, it updates them but doesn't want to get alerted about its own
* updates. It also won't be alerted about other clients' updates, so this
* is suitable only for use by a client that "owns" a particular column.
+ * Use ovsdb_idl_omit_alert() to set a column that is already replicated to
+ * this mode.
*
* - OVDSB_IDL_ALERT without OVSDB_IDL_MONITOR is not valid.
*
* that a client wants to track using the change tracking
* ovsdb_idl_track_get_*() functions.
*/
-#define OVSDB_IDL_MONITOR (1 << 0) /* Monitor this column? */
-#define OVSDB_IDL_ALERT (1 << 1) /* Alert client when column updated? */
+#define OVSDB_IDL_MONITOR (1 << 0) /* Replicate this column? */
+#define OVSDB_IDL_ALERT (1 << 1) /* Alert client when column changes? */
#define OVSDB_IDL_TRACK (1 << 2)
void ovsdb_idl_add_column(struct ovsdb_idl *, const struct ovsdb_idl_column *);
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