-/* Copyright (c) 2009 Nicira Networks.
+/* Copyright (c) 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#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;
struct ovsdb_idl_class;
+struct ovsdb_idl_column;
+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,
+ bool retry);
void ovsdb_idl_destroy(struct ovsdb_idl *);
void ovsdb_idl_run(struct ovsdb_idl *);
void ovsdb_idl_wait(struct ovsdb_idl *);
+void ovsdb_idl_set_lock(struct ovsdb_idl *, const char *lock_name);
+bool ovsdb_idl_has_lock(const struct ovsdb_idl *);
+bool ovsdb_idl_is_lock_contended(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_force_reconnect(struct ovsdb_idl *);
+void ovsdb_idl_verify_write_only(struct ovsdb_idl *);
+
+bool ovsdb_idl_is_alive(const struct ovsdb_idl *);
+int ovsdb_idl_get_last_error(const 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 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 *,
+ const struct uuid *);
+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.
+ *
+ * A transaction may modify the contents of a database by modifying the values
+ * of columns, deleting rows, inserting rows, or adding checks that columns in
+ * the database have not changed ("verify" operations), through
+ * ovsdb_idl_txn_*() functions. (The OVSDB IDL code generator produces helper
+ * functions that internally call the ovsdb_idl_txn_*() functions. These are
+ * likely to be more convenient.)
+ *
+ * Reading and writing columns and inserting and deleting rows are all
+ * straightforward. The reasons to verify columns are less obvious.
+ * Verification is the key to maintaining transactional integrity. Because
+ * OVSDB handles multiple clients, it can happen that between the time that
+ * OVSDB client A reads a column and writes a new value, OVSDB client B has
+ * written that column. Client A's write should not ordinarily overwrite
+ * client B's, especially if the column in question is a "map" column that
+ * contains several more or less independent data items. If client A adds a
+ * "verify" operation before it writes the column, then the transaction fails
+ * in case client B modifies it first. Client A will then see the new value of
+ * the column and compose a new transaction based on the new contents written
+ * by client B.
+ *
+ * When a transaction is complete, which must be before the next call to
+ * ovsdb_idl_run() on 'idl', call ovsdb_idl_txn_commit() or
+ * ovsdb_idl_txn_abort().
+ *
+ * The life-cycle of a transaction looks like this:
+ *
+ * 1. Create the transaction and record the initial sequence number:
+ *
+ * seqno = ovsdb_idl_get_seqno(idl);
+ * txn = ovsdb_idl_txn_create(idl);
+ *
+ * 2. Modify the database with ovsdb_idl_txn_*() functions directly or
+ * indirectly.
+ *
+ * 3. Commit the transaction by calling ovsdb_idl_txn_commit(). The first call
+ * to this function probably returns TXN_INCOMPLETE. The client must keep
+ * calling again along as this remains true, calling ovsdb_idl_run() in
+ * between to let the IDL do protocol processing. (If the client doesn't
+ * have anything else to do in the meantime, it can use
+ * ovsdb_idl_txn_commit_block() to avoid having to loop itself.)
+ *
+ * 4. If the final status is TXN_TRY_AGAIN, wait for ovsdb_idl_get_seqno() to
+ * change from the saved 'seqno' (it's possible that it's already changed,
+ * in which case the client should not wait at all), then start over from
+ * step 1. Only a call to ovsdb_idl_run() will change the return value of
+ * ovsdb_idl_get_seqno(). (ovsdb_idl_txn_commit_block() calls
+ * ovsdb_idl_run().)
+ */
enum ovsdb_idl_txn_status {
+ TXN_UNCOMMITTED, /* Not yet committed or aborted. */
+ TXN_UNCHANGED, /* Transaction didn't include any changes. */
TXN_INCOMPLETE, /* Commit in progress, please wait. */
TXN_ABORTED, /* ovsdb_idl_txn_abort() called. */
TXN_SUCCESS, /* Commit successful. */
TXN_TRY_AGAIN, /* Commit failed because a "verify" operation
* reported an inconsistency, due to a network
- * problem, or other transient failure. */
+ * problem, or other transient failure. Wait
+ * for a change, then try again. */
+ TXN_NOT_LOCKED, /* Server hasn't given us the lock yet. */
TXN_ERROR /* Commit failed due to a hard error. */
};
const char *ovsdb_idl_txn_status_to_string(enum ovsdb_idl_txn_status);
struct ovsdb_idl_txn *ovsdb_idl_txn_create(struct ovsdb_idl *);
-void ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *, const char *);
+void ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *, const char *, ...)
+ PRINTF_FORMAT (2, 3);
void ovsdb_idl_txn_set_dry_run(struct ovsdb_idl_txn *);
+void ovsdb_idl_txn_increment(struct ovsdb_idl_txn *,
+ const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *);
void ovsdb_idl_txn_destroy(struct ovsdb_idl_txn *);
void ovsdb_idl_txn_wait(const struct ovsdb_idl_txn *);
enum ovsdb_idl_txn_status ovsdb_idl_txn_commit(struct ovsdb_idl_txn *);
+enum ovsdb_idl_txn_status ovsdb_idl_txn_commit_block(struct ovsdb_idl_txn *);
void ovsdb_idl_txn_abort(struct ovsdb_idl_txn *);
+const char *ovsdb_idl_txn_get_error(const struct ovsdb_idl_txn *);
+
+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_write(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ struct ovsdb_datum *);
+void ovsdb_idl_txn_write_clone(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ const struct ovsdb_datum *);
+void ovsdb_idl_txn_delete(const struct ovsdb_idl_row *);
+const struct ovsdb_idl_row *ovsdb_idl_txn_insert(
+ struct ovsdb_idl_txn *, const struct ovsdb_idl_table_class *,
+ const struct uuid *);
+
+struct ovsdb_idl *ovsdb_idl_txn_get_idl (struct ovsdb_idl_txn *);
+
#endif /* ovsdb-idl.h */
git://git.onelab.eu / sliver-openvswitch.git / blobdiff