Prepare Open vSwitch 1.1.2 release.

[sliver-openvswitch.git] / lib / ovsdb-idl.h

diff --git a/lib/ovsdb-idl.h b/lib/ovsdb-idl.h
index 31fae98..d11fb0e 100644 (file)
--- a/lib/ovsdb-idl.h
+++ b/lib/ovsdb-idl.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2009, 2010 Nicira Networks.
+/* Copyright (c) 2009, 2010, 2011 Nicira Networks.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,9 +16,24 @@
 #ifndef OVSDB_IDL_H
 #define OVSDB_IDL_H 1
 
+/* Open vSwitch Database Interface Definition Language (OVSDB IDL).
+ *
+ * The OVSDB IDL maintains an in-memory replica of a database.  It issues RPC
+ * requests to an OVSDB database server and parses the responses, converting
+ * raw JSON into data structures that are easier for clients to digest.  Most
+ * notably, references to rows via UUID become C pointers.
+ *
+ * The IDL also assists with issuing database transactions.  The client creates
+ * a transaction, manipulates the IDL data structures, and commits or aborts
+ * the transaction.  The IDL then composes and issues the necessary JSON-RPC
+ * requests and reports to the client whether the transaction completed
+ * successfully.
+ */
+
 #include <stdbool.h>
 #include <stdint.h>
 #include "compiler.h"
+#include "ovsdb-types.h"
 
 struct json;
 struct ovsdb_datum;
@@ -28,15 +43,54 @@ struct ovsdb_idl_table_class;
 struct uuid;
 
 struct ovsdb_idl *ovsdb_idl_create(const char *remote,
-                                   const struct ovsdb_idl_class *);
+                                   const struct ovsdb_idl_class *,
+                                   bool monitor_everything_by_default);
 void ovsdb_idl_destroy(struct ovsdb_idl *);
 
-void ovsdb_idl_run(struct ovsdb_idl *);
+bool ovsdb_idl_run(struct ovsdb_idl *);
 void ovsdb_idl_wait(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_force_reconnect(struct ovsdb_idl *);
+\f
+/* Choosing columns and tables to replicate. */
+
+/* Modes with which the IDL can monitor a column.
+ *
+ * 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 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
+ * ovsdb_idl_run() will return "true", and the value returned by
+ * ovsdb_idl_get_seqno() will change, when the column's value changes.
+ *
+ * The possible mode combinations are:
+ *
+ *   - 0, for a column that a client doesn't care about.
+ *
+ *   - (OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT), for a column that a client wants
+ *     to track and possibly update.
+ *
+ *   - 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.
+ *
+ *   - OVDSB_IDL_ALERT without OVSDB_IDL_MONITOR is not valid.
+ */
+#define OVSDB_IDL_MONITOR (1 << 0) /* Monitor this column? */
+#define OVSDB_IDL_ALERT   (1 << 1) /* Alert client when column updated? */
+
+void ovsdb_idl_add_column(struct ovsdb_idl *, const struct ovsdb_idl_column *);
+void ovsdb_idl_add_table(struct ovsdb_idl *,
+                         const struct ovsdb_idl_table_class *);
+
+void ovsdb_idl_omit(struct ovsdb_idl *, const struct ovsdb_idl_column *);
+void ovsdb_idl_omit_alert(struct ovsdb_idl *, const struct ovsdb_idl_column *);
+\f
+/* Reading the database replica. */
 
 const struct ovsdb_idl_row *ovsdb_idl_get_row_for_uuid(
     const struct ovsdb_idl *, const struct ovsdb_idl_table_class *,
@@ -45,6 +99,17 @@ const struct ovsdb_idl_row *ovsdb_idl_first_row(
     const struct ovsdb_idl *, const struct ovsdb_idl_table_class *);
 const struct ovsdb_idl_row *ovsdb_idl_next_row(const struct ovsdb_idl_row *);
 
+const struct ovsdb_datum *ovsdb_idl_read(const struct ovsdb_idl_row *,
+                                         const struct ovsdb_idl_column *);
+const struct ovsdb_datum *ovsdb_idl_get(const struct ovsdb_idl_row *,
+                                        const struct ovsdb_idl_column *,
+                                        enum ovsdb_atomic_type key_type,
+                                        enum ovsdb_atomic_type value_type);
+
+bool ovsdb_idl_row_is_synthetic(const struct ovsdb_idl_row *);
+\f
+/* Transactions. */
+
 enum ovsdb_idl_txn_status {
     TXN_UNCHANGED,              /* Transaction didn't include any changes. */
     TXN_INCOMPLETE,             /* Commit in progress, please wait. */
@@ -76,9 +141,6 @@ int64_t ovsdb_idl_txn_get_increment_new_value(const struct ovsdb_idl_txn *);
 const struct uuid *ovsdb_idl_txn_get_insert_uuid(const struct ovsdb_idl_txn *,
                                                  const struct uuid *);
 
-void ovsdb_idl_txn_read(const struct ovsdb_idl_row *,
-                        const struct ovsdb_idl_column *,
-                        struct ovsdb_datum *);
 void ovsdb_idl_txn_write(const struct ovsdb_idl_row *,
                          const struct ovsdb_idl_column *,
                          struct ovsdb_datum *);