-/* Copyright (c) 2009, 2010 Nicira Networks.
+/* 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");
* 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 always presents a consistent snapshot of the database to its client,
+ * that is, it won't present the effects of some part of a transaction applied
+ * at the database server without presenting all of its effects.
+ *
+ * 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"
+#include "ovsdb-data.h"
+#include "openvswitch/list.h"
+#include "ovsdb-condition.h"
+#include "skiplist.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
struct json;
struct ovsdb_datum;
struct ovsdb_idl_class;
+struct ovsdb_idl_row;
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);
+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);
+
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 *);
+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);
+
+void ovsdb_idl_check_consistency(const struct ovsdb_idl *);
+
+const struct ovsdb_idl_class *ovsdb_idl_get_class(const struct ovsdb_idl *);
+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.
+ *
+ * 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 replicate a column. See above comment for
+ * overview.
+ *
+ * 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 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. 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. 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.
+ *
+ * - (OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT | OVSDB_IDL_TRACK), for a column
+ * that a client wants to track using the change tracking
+ * ovsdb_idl_track_get_*() functions.
+ */
+#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 *);
+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 *);
+
+/* Change tracking.
+ *
+ * In OVSDB, change tracking is applied at each client in the IDL layer. This
+ * means that when a client makes a request to track changes on a particular
+ * table, they are essentially requesting information about the incremental
+ * changes to that table from the point in time that the request is made. Once
+ * the client clears tracked changes, that information will no longer be
+ * available.
+ *
+ * The implication of the above is that if a client requires replaying
+ * untracked history, it faces the choice of either trying to remember changes
+ * itself (which translates into a memory leak) or of being structured with a
+ * path for processing the full untracked table as well as a path that
+ * processes incremental changes. */
+enum ovsdb_idl_change {
+ OVSDB_IDL_CHANGE_INSERT,
+ OVSDB_IDL_CHANGE_MODIFY,
+ OVSDB_IDL_CHANGE_DELETE,
+ OVSDB_IDL_CHANGE_MAX
+};
+
+/* Row, table sequence numbers */
+unsigned int ovsdb_idl_table_get_seqno(
+ const struct ovsdb_idl *idl,
+ const struct ovsdb_idl_table_class *table_class);
+unsigned int ovsdb_idl_row_get_seqno(
+ const struct ovsdb_idl_row *row,
+ enum ovsdb_idl_change change);
+
+void ovsdb_idl_track_add_column(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column);
+void ovsdb_idl_track_add_all(struct ovsdb_idl *idl);
+const struct ovsdb_idl_row *ovsdb_idl_track_get_first(
+ const struct ovsdb_idl *, const struct ovsdb_idl_table_class *);
+const struct ovsdb_idl_row *ovsdb_idl_track_get_next(const struct ovsdb_idl_row *);
+bool ovsdb_idl_track_is_updated(const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column);
+void ovsdb_idl_track_clear(struct ovsdb_idl *);
+
+\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 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_is_mutable(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *);
+
+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 *, ...)
+ OVS_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 char *table,
- const char *column, const struct json *where);
+void ovsdb_idl_txn_increment(struct ovsdb_idl_txn *,
+ const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ bool force);
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 *);
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 *);
+void ovsdb_idl_txn_write_clone(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ const struct ovsdb_datum *);
+void ovsdb_idl_txn_write_partial_map(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ struct ovsdb_datum *);
+void ovsdb_idl_txn_delete_partial_map(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ struct ovsdb_datum *);
+void ovsdb_idl_txn_write_partial_set(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ struct ovsdb_datum *);
+void ovsdb_idl_txn_delete_partial_set(const struct ovsdb_idl_row *,
+ const struct ovsdb_idl_column *,
+ 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 *);
+ 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 *);
+void ovsdb_idl_get_initial_snapshot(struct ovsdb_idl *);
+\f
+
+/* ovsdb_idl_loop provides an easy way to manage the transactions related
+ * to 'idl' and to cope with different status during transaction. */
+struct ovsdb_idl_loop {
+ struct ovsdb_idl *idl;
+ unsigned int skip_seqno;
+
+ struct ovsdb_idl_txn *committing_txn;
+ unsigned int precommit_seqno;
+
+ struct ovsdb_idl_txn *open_txn;
+
+ /* These members allow a client a simple, stateless way to keep track of
+ * transactions that commit: when a transaction commits successfully,
+ * ovsdb_idl_loop_commit_and_wait() copies 'next_cfg' to 'cur_cfg'. Thus,
+ * the client can set 'next_cfg' to a value that indicates a successful
+ * commit and check 'cur_cfg' on each iteration. */
+ int64_t cur_cfg;
+ int64_t next_cfg;
+};
+
+#define OVSDB_IDL_LOOP_INITIALIZER(IDL) { .idl = (IDL) }
+
+void ovsdb_idl_loop_destroy(struct ovsdb_idl_loop *);
+struct ovsdb_idl_txn *ovsdb_idl_loop_run(struct ovsdb_idl_loop *);
+int ovsdb_idl_loop_commit_and_wait(struct ovsdb_idl_loop *);
+\f
+/* Conditional Replication
+ * =======================
+ *
+ * By default, when the IDL replicates a particular table in the database, it
+ * replicates every row in the table. These functions allow the client to
+ * specify that only selected rows should be replicated, by constructing a
+ * per-table condition that specifies the rows to replicate.
+ *
+ * A condition is a disjunction of clauses. The condition is true, and thus a
+ * row is replicated, if any of the clauses evaluates to true for a given row.
+ * (Thus, a condition with no clauses is always false.)
+ */
+
+struct ovsdb_idl_condition {
+ struct hmap clauses; /* Contains "struct ovsdb_idl_clause"s. */
+ bool is_true; /* Is the condition unconditionally true? */
+};
+#define OVSDB_IDL_CONDITION_INIT(CONDITION) \
+ { HMAP_INITIALIZER(&(CONDITION)->clauses), false }
+
+void ovsdb_idl_condition_init(struct ovsdb_idl_condition *);
+void ovsdb_idl_condition_clear(struct ovsdb_idl_condition *);
+void ovsdb_idl_condition_destroy(struct ovsdb_idl_condition *);
+void ovsdb_idl_condition_add_clause(struct ovsdb_idl_condition *,
+ enum ovsdb_function function,
+ const struct ovsdb_idl_column *column,
+ const struct ovsdb_datum *arg);
+void ovsdb_idl_condition_add_clause_true(struct ovsdb_idl_condition *);
+bool ovsdb_idl_condition_is_true(const struct ovsdb_idl_condition *);
+
+unsigned int ovsdb_idl_set_condition(struct ovsdb_idl *,
+ const struct ovsdb_idl_table_class *,
+ const struct ovsdb_idl_condition *);
+
+unsigned int ovsdb_idl_get_condition_seqno(const struct ovsdb_idl *);
+\f
+/* Indexes over one or more columns in the IDL, to retrieve rows matching
+ * particular search criteria and to iterate over a subset of rows in a defined
+ * order. */
+
+enum ovsdb_index_order {
+ OVSDB_INDEX_ASC, /* 0, 1, 2, ... */
+ OVSDB_INDEX_DESC /* 2, 1, 0, ... */
+};
+
+typedef int column_comparator_func(const void *a, const void *b);
+
+struct ovsdb_idl_index_column {
+ const struct ovsdb_idl_column *column;
+ column_comparator_func *comparer;
+ enum ovsdb_index_order order;
+};
+
+/* Creating an index. */
+struct ovsdb_idl_index *ovsdb_idl_index_create(
+ struct ovsdb_idl *, const struct ovsdb_idl_index_column *, size_t n);
+struct ovsdb_idl_index *ovsdb_idl_index_create1(
+ struct ovsdb_idl *, const struct ovsdb_idl_column *);
+struct ovsdb_idl_index *ovsdb_idl_index_create2(
+ struct ovsdb_idl *, const struct ovsdb_idl_column *,
+ const struct ovsdb_idl_column *);
+
+/* Searching an index. */
+struct ovsdb_idl_row *ovsdb_idl_index_find(struct ovsdb_idl_index *,
+ const struct ovsdb_idl_row *);
+\f
+/* Iteration over an index.
+ *
+ * Usually these would be invoked through table-specific wrappers generated
+ * by the IDL. */
+
+struct ovsdb_idl_cursor {
+ struct ovsdb_idl_index *index; /* Index being iterated. */
+ struct skiplist_node *position; /* Current position in 'index'. */
+};
+
+struct ovsdb_idl_cursor ovsdb_idl_cursor_first(struct ovsdb_idl_index *);
+struct ovsdb_idl_cursor ovsdb_idl_cursor_first_eq(
+ struct ovsdb_idl_index *, const struct ovsdb_idl_row *);
+struct ovsdb_idl_cursor ovsdb_idl_cursor_first_ge(
+ struct ovsdb_idl_index *, const struct ovsdb_idl_row *);
+
+void ovsdb_idl_cursor_next(struct ovsdb_idl_cursor *);
+void ovsdb_idl_cursor_next_eq(struct ovsdb_idl_cursor *);
+
+struct ovsdb_idl_row *ovsdb_idl_cursor_data(struct ovsdb_idl_cursor *);
+
+#ifdef __cplusplus
+}
+#endif
#endif /* ovsdb-idl.h */
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