-/* Copyright (c) 2009, 2010 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.
#include "ovsdb-idl.h"
-#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include "bitmap.h"
#include "dynamic-string.h"
+#include "fatal-signal.h"
#include "json.h"
#include "jsonrpc.h"
#include "ovsdb-data.h"
#include "poll-loop.h"
#include "shash.h"
#include "util.h"
-
-#define THIS_MODULE VLM_ovsdb_idl
#include "vlog.h"
+VLOG_DEFINE_THIS_MODULE(ovsdb_idl);
+
/* An arc from one idl_row to another. When row A contains a UUID that
* references row B, this is represented by an arc from A (the source) to B
* (the destination).
const struct ovsdb_idl_class *class;
struct jsonrpc_session *session;
struct shash table_by_name;
- struct ovsdb_idl_table *tables;
+ struct ovsdb_idl_table *tables; /* Contains "struct ovsdb_idl_table *"s.*/
struct json *monitor_request_id;
unsigned int last_monitor_request_seqno;
unsigned int change_seqno;
+ bool verify_write_only;
+
+ /* Database locking. */
+ char *lock_name; /* Name of lock we need, NULL if none. */
+ bool has_lock; /* Has db server told us we have the lock? */
+ bool is_lock_contended; /* Has db server told us we can't get lock? */
+ struct json *lock_request_id; /* JSON-RPC ID of in-flight lock request. */
/* Transaction support. */
struct ovsdb_idl_txn *txn;
struct ovsdb_idl *idl;
struct hmap txn_rows;
enum ovsdb_idl_txn_status status;
+ char *error;
bool dry_run;
struct ds comment;
/* Increments. */
- char *inc_table;
- char *inc_column;
- struct json *inc_where;
+ const char *inc_table;
+ const char *inc_column;
+ struct uuid inc_row;
unsigned int inc_index;
int64_t inc_new_value;
+
+ /* Inserted rows. */
+ struct hmap inserted_rows; /* Contains "struct ovsdb_idl_txn_insert"s. */
+};
+
+struct ovsdb_idl_txn_insert {
+ struct hmap_node hmap_node; /* In struct ovsdb_idl_txn's inserted_rows. */
+ struct uuid dummy; /* Dummy UUID used locally. */
+ int op_index; /* Index into transaction's operation array. */
+ struct uuid real; /* Real UUID used by database server. */
};
static struct vlog_rate_limit syntax_rl = VLOG_RATE_LIMIT_INIT(1, 5);
static void ovsdb_idl_parse_update(struct ovsdb_idl *, const struct json *);
static struct ovsdb_error *ovsdb_idl_parse_update__(struct ovsdb_idl *,
const struct json *);
-static void ovsdb_idl_process_update(struct ovsdb_idl_table *,
+static bool ovsdb_idl_process_update(struct ovsdb_idl_table *,
const struct uuid *,
const struct json *old,
const struct json *new);
static void ovsdb_idl_insert_row(struct ovsdb_idl_row *, const struct json *);
static void ovsdb_idl_delete_row(struct ovsdb_idl_row *);
-static void ovsdb_idl_modify_row(struct ovsdb_idl_row *, const struct json *);
+static bool ovsdb_idl_modify_row(struct ovsdb_idl_row *, const struct json *);
static bool ovsdb_idl_row_is_orphan(const struct ovsdb_idl_row *);
static struct ovsdb_idl_row *ovsdb_idl_row_create__(
const struct uuid *);
static void ovsdb_idl_row_destroy(struct ovsdb_idl_row *);
+static void ovsdb_idl_row_parse(struct ovsdb_idl_row *);
+static void ovsdb_idl_row_unparse(struct ovsdb_idl_row *);
static void ovsdb_idl_row_clear_old(struct ovsdb_idl_row *);
static void ovsdb_idl_row_clear_new(struct ovsdb_idl_row *);
static bool ovsdb_idl_txn_process_reply(struct ovsdb_idl *,
const struct jsonrpc_msg *msg);
+static void ovsdb_idl_send_lock_request(struct ovsdb_idl *);
+static void ovsdb_idl_send_unlock_request(struct ovsdb_idl *);
+static void ovsdb_idl_parse_lock_reply(struct ovsdb_idl *,
+ const struct json *);
+static void ovsdb_idl_parse_lock_notify(struct ovsdb_idl *,
+ const struct json *params,
+ bool new_has_lock);
+
+/* Creates and returns a connection to database 'remote', which should be in a
+ * form acceptable to jsonrpc_session_open(). The connection will maintain an
+ * in-memory replica of the remote database whose schema is described by
+ * 'class'. (Ordinarily 'class' is compiled from an OVSDB schema automatically
+ * by ovsdb-idlc.)
+ *
+ * Passes 'retry' to jsonrpc_session_open(). See that function for
+ * documentation.
+ *
+ * If 'monitor_everything_by_default' is true, then everything in the remote
+ * database will be replicated by default. ovsdb_idl_omit() and
+ * ovsdb_idl_omit_alert() may be used to selectively drop some columns from
+ * monitoring.
+ *
+ * If 'monitor_everything_by_default' is false, then no columns or tables will
+ * be replicated by default. ovsdb_idl_add_column() and ovsdb_idl_add_table()
+ * must be used to choose some columns or tables to replicate.
+ */
struct ovsdb_idl *
-ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class)
+ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class,
+ bool monitor_everything_by_default, bool retry)
{
struct ovsdb_idl *idl;
+ uint8_t default_mode;
size_t i;
+ default_mode = (monitor_everything_by_default
+ ? OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT
+ : 0);
+
idl = xzalloc(sizeof *idl);
idl->class = class;
- idl->session = jsonrpc_session_open(remote);
+ idl->session = jsonrpc_session_open(remote, retry);
shash_init(&idl->table_by_name);
idl->tables = xmalloc(class->n_tables * sizeof *idl->tables);
for (i = 0; i < class->n_tables; i++) {
struct ovsdb_idl_table *table = &idl->tables[i];
size_t j;
- assert(!shash_find(&idl->table_by_name, tc->name));
- shash_add(&idl->table_by_name, tc->name, table);
+ shash_add_assert(&idl->table_by_name, tc->name, table);
table->class = tc;
+ table->modes = xmalloc(tc->n_columns);
+ memset(table->modes, default_mode, tc->n_columns);
+ table->need_table = false;
shash_init(&table->columns);
for (j = 0; j < tc->n_columns; j++) {
const struct ovsdb_idl_column *column = &tc->columns[j];
- assert(!shash_find(&table->columns, column->name));
- shash_add(&table->columns, column->name, column);
+ shash_add_assert(&table->columns, column->name, column);
}
hmap_init(&table->rows);
table->idl = idl;
return idl;
}
+/* Destroys 'idl' and all of the data structures that it manages. */
void
ovsdb_idl_destroy(struct ovsdb_idl *idl)
{
if (idl) {
size_t i;
- assert(!idl->txn);
+ ovs_assert(!idl->txn);
ovsdb_idl_clear(idl);
jsonrpc_session_close(idl->session);
struct ovsdb_idl_table *table = &idl->tables[i];
shash_destroy(&table->columns);
hmap_destroy(&table->rows);
+ free(table->modes);
}
shash_destroy(&idl->table_by_name);
free(idl->tables);
json_destroy(idl->monitor_request_id);
+ free(idl->lock_name);
+ json_destroy(idl->lock_request_id);
+ hmap_destroy(&idl->outstanding_txns);
free(idl);
}
}
}
changed = true;
- HMAP_FOR_EACH_SAFE (row, next_row, struct ovsdb_idl_row, hmap_node,
- &table->rows) {
+ HMAP_FOR_EACH_SAFE (row, next_row, hmap_node, &table->rows) {
struct ovsdb_idl_arc *arc, *next_arc;
if (!ovsdb_idl_row_is_orphan(row)) {
- (row->table->class->unparse)(row);
- ovsdb_idl_row_clear_old(row);
+ ovsdb_idl_row_unparse(row);
}
- hmap_remove(&table->rows, &row->hmap_node);
- LIST_FOR_EACH_SAFE (arc, next_arc, struct ovsdb_idl_arc, src_node,
- &row->src_arcs) {
+ LIST_FOR_EACH_SAFE (arc, next_arc, src_node, &row->src_arcs) {
free(arc);
}
/* No need to do anything with dst_arcs: some node has those arcs
* as forward arcs and will destroy them itself. */
- free(row);
+ ovsdb_idl_row_destroy(row);
}
}
}
}
+/* Processes a batch of messages from the database server on 'idl'. This may
+ * cause the IDL's contents to change. The client may check for that with
+ * ovsdb_idl_get_seqno(). */
void
ovsdb_idl_run(struct ovsdb_idl *idl)
{
int i;
- assert(!idl->txn);
+ ovs_assert(!idl->txn);
jsonrpc_session_run(idl->session);
for (i = 0; jsonrpc_session_is_connected(idl->session) && i < 50; i++) {
- struct jsonrpc_msg *msg, *reply;
+ struct jsonrpc_msg *msg;
unsigned int seqno;
seqno = jsonrpc_session_get_seqno(idl->session);
idl->last_monitor_request_seqno = seqno;
ovsdb_idl_txn_abort_all(idl);
ovsdb_idl_send_monitor_request(idl);
+ if (idl->lock_name) {
+ ovsdb_idl_send_lock_request(idl);
+ }
break;
}
break;
}
- reply = NULL;
if (msg->type == JSONRPC_NOTIFY
- && !strcmp(msg->method, "update")
- && msg->params->type == JSON_ARRAY
- && msg->params->u.array.n == 2
- && msg->params->u.array.elems[0]->type == JSON_NULL) {
+ && !strcmp(msg->method, "update")
+ && msg->params->type == JSON_ARRAY
+ && msg->params->u.array.n == 2
+ && msg->params->u.array.elems[0]->type == JSON_NULL) {
+ /* Database contents changed. */
ovsdb_idl_parse_update(idl, msg->params->u.array.elems[1]);
} else if (msg->type == JSONRPC_REPLY
&& idl->monitor_request_id
&& json_equal(idl->monitor_request_id, msg->id)) {
+ /* Reply to our "monitor" request. */
+ idl->change_seqno++;
json_destroy(idl->monitor_request_id);
idl->monitor_request_id = NULL;
ovsdb_idl_clear(idl);
ovsdb_idl_parse_update(idl, msg->result);
} else if (msg->type == JSONRPC_REPLY
- && msg->id && msg->id->type == JSON_STRING
- && !strcmp(msg->id->u.string, "echo")) {
- /* It's a reply to our echo request. Ignore it. */
+ && idl->lock_request_id
+ && json_equal(idl->lock_request_id, msg->id)) {
+ /* Reply to our "lock" request. */
+ ovsdb_idl_parse_lock_reply(idl, msg->result);
+ } else if (msg->type == JSONRPC_NOTIFY
+ && !strcmp(msg->method, "locked")) {
+ /* We got our lock. */
+ ovsdb_idl_parse_lock_notify(idl, msg->params, true);
+ } else if (msg->type == JSONRPC_NOTIFY
+ && !strcmp(msg->method, "stolen")) {
+ /* Someone else stole our lock. */
+ ovsdb_idl_parse_lock_notify(idl, msg->params, false);
} else if ((msg->type == JSONRPC_ERROR
|| msg->type == JSONRPC_REPLY)
&& ovsdb_idl_txn_process_reply(idl, msg)) {
jsonrpc_session_get_name(idl->session),
jsonrpc_msg_type_to_string(msg->type));
}
- if (reply) {
- jsonrpc_session_send(idl->session, reply);
- }
jsonrpc_msg_destroy(msg);
}
}
+/* Arranges for poll_block() to wake up when ovsdb_idl_run() has something to
+ * do or when activity occurs on a transaction on 'idl'. */
void
ovsdb_idl_wait(struct ovsdb_idl *idl)
{
jsonrpc_session_recv_wait(idl->session);
}
+/* Returns a "sequence number" that represents the state of 'idl'. When
+ * ovsdb_idl_run() changes the database, the sequence number changes. The
+ * initial fetch of the entire contents of the remote database is considered to
+ * be one kind of change. Successfully acquiring a lock, if one has been
+ * configured with ovsdb_idl_set_lock(), is also considered to be a change.
+ *
+ * As long as the sequence number does not change, the client may continue to
+ * use any data structures it obtains from 'idl'. But when it changes, the
+ * client must not access any of these data structures again, because they
+ * could have freed or reused for other purposes.
+ *
+ * The sequence number can occasionally change even if the database does not.
+ * This happens if the connection to the database drops and reconnects, which
+ * causes the database contents to be reloaded even if they didn't change. (It
+ * could also happen if the database server sends out a "change" that reflects
+ * what the IDL already thought was in the database. The database server is
+ * not supposed to do that, but bugs could in theory cause it to do so.) */
unsigned int
ovsdb_idl_get_seqno(const struct ovsdb_idl *idl)
{
return idl->change_seqno;
}
+/* Returns true if 'idl' successfully connected to the remote database and
+ * retrieved its contents (even if the connection subsequently dropped and is
+ * in the process of reconnecting). If so, then 'idl' contains an atomic
+ * snapshot of the database's contents (but it might be arbitrarily old if the
+ * connection dropped).
+ *
+ * Returns false if 'idl' has never connected or retrieved the database's
+ * contents. If so, 'idl' is empty. */
bool
ovsdb_idl_has_ever_connected(const struct ovsdb_idl *idl)
{
return ovsdb_idl_get_seqno(idl) != 0;
}
+/* Reconfigures 'idl' so that it would reconnect to the database, if
+ * connection was dropped. */
+void
+ovsdb_idl_enable_reconnect(struct ovsdb_idl *idl)
+{
+ jsonrpc_session_enable_reconnect(idl->session);
+}
+
+/* Forces 'idl' to drop its connection to the database and reconnect. In the
+ * meantime, the contents of 'idl' will not change. */
void
ovsdb_idl_force_reconnect(struct ovsdb_idl *idl)
{
jsonrpc_session_force_reconnect(idl->session);
}
+
+/* Some IDL users should only write to write-only columns. Furthermore,
+ * writing to a column which is not write-only can cause serious performance
+ * degradations for these users. This function causes 'idl' to reject writes
+ * to columns which are not marked write only using ovsdb_idl_omit_alert(). */
+void
+ovsdb_idl_verify_write_only(struct ovsdb_idl *idl)
+{
+ idl->verify_write_only = true;
+}
+
+bool
+ovsdb_idl_is_alive(const struct ovsdb_idl *idl)
+{
+ return jsonrpc_session_is_alive(idl->session);
+}
+
+int
+ovsdb_idl_get_last_error(const struct ovsdb_idl *idl)
+{
+ return jsonrpc_session_get_last_error(idl->session);
+}
+\f
+static unsigned char *
+ovsdb_idl_get_mode(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column)
+{
+ size_t i;
+
+ ovs_assert(!idl->change_seqno);
+
+ for (i = 0; i < idl->class->n_tables; i++) {
+ const struct ovsdb_idl_table *table = &idl->tables[i];
+ const struct ovsdb_idl_table_class *tc = table->class;
+
+ if (column >= tc->columns && column < &tc->columns[tc->n_columns]) {
+ return &table->modes[column - tc->columns];
+ }
+ }
+
+ OVS_NOT_REACHED();
+}
+
+static void
+add_ref_table(struct ovsdb_idl *idl, const struct ovsdb_base_type *base)
+{
+ if (base->type == OVSDB_TYPE_UUID && base->u.uuid.refTableName) {
+ struct ovsdb_idl_table *table;
+
+ table = shash_find_data(&idl->table_by_name,
+ base->u.uuid.refTableName);
+ if (table) {
+ table->need_table = true;
+ } else {
+ VLOG_WARN("%s IDL class missing referenced table %s",
+ idl->class->database, base->u.uuid.refTableName);
+ }
+ }
+}
+
+/* Turns on OVSDB_IDL_MONITOR and OVSDB_IDL_ALERT for 'column' in 'idl'. Also
+ * ensures that any tables referenced by 'column' will be replicated, even if
+ * no columns in that table are selected for replication (see
+ * ovsdb_idl_add_table() for more information).
+ *
+ * This function is only useful if 'monitor_everything_by_default' was false in
+ * the call to ovsdb_idl_create(). This function should be called between
+ * ovsdb_idl_create() and the first call to ovsdb_idl_run().
+ */
+void
+ovsdb_idl_add_column(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column)
+{
+ *ovsdb_idl_get_mode(idl, column) = OVSDB_IDL_MONITOR | OVSDB_IDL_ALERT;
+ add_ref_table(idl, &column->type.key);
+ add_ref_table(idl, &column->type.value);
+}
+
+/* Ensures that the table with class 'tc' will be replicated on 'idl' even if
+ * no columns are selected for replication. This can be useful because it
+ * allows 'idl' to keep track of what rows in the table actually exist, which
+ * in turn allows columns that reference the table to have accurate contents.
+ * (The IDL presents the database with references to rows that do not exist
+ * removed.)
+ *
+ * This function is only useful if 'monitor_everything_by_default' was false in
+ * the call to ovsdb_idl_create(). This function should be called between
+ * ovsdb_idl_create() and the first call to ovsdb_idl_run().
+ */
+void
+ovsdb_idl_add_table(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_table_class *tc)
+{
+ size_t i;
+
+ for (i = 0; i < idl->class->n_tables; i++) {
+ struct ovsdb_idl_table *table = &idl->tables[i];
+
+ if (table->class == tc) {
+ table->need_table = true;
+ return;
+ }
+ }
+
+ OVS_NOT_REACHED();
+}
+
+/* Turns off OVSDB_IDL_ALERT for 'column' in 'idl'.
+ *
+ * This function should be called between ovsdb_idl_create() and the first call
+ * to ovsdb_idl_run().
+ */
+void
+ovsdb_idl_omit_alert(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column)
+{
+ *ovsdb_idl_get_mode(idl, column) &= ~OVSDB_IDL_ALERT;
+}
+
+/* Sets the mode for 'column' in 'idl' to 0. See the big comment above
+ * OVSDB_IDL_MONITOR for details.
+ *
+ * This function should be called between ovsdb_idl_create() and the first call
+ * to ovsdb_idl_run().
+ */
+void
+ovsdb_idl_omit(struct ovsdb_idl *idl, const struct ovsdb_idl_column *column)
+{
+ *ovsdb_idl_get_mode(idl, column) = 0;
+}
\f
static void
ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl)
const struct ovsdb_idl_table *table = &idl->tables[i];
const struct ovsdb_idl_table_class *tc = table->class;
struct json *monitor_request, *columns;
- size_t i;
+ size_t j;
+
+ columns = table->need_table ? json_array_create_empty() : NULL;
+ for (j = 0; j < tc->n_columns; j++) {
+ const struct ovsdb_idl_column *column = &tc->columns[j];
+ if (table->modes[j] & OVSDB_IDL_MONITOR) {
+ if (!columns) {
+ columns = json_array_create_empty();
+ }
+ json_array_add(columns, json_string_create(column->name));
+ }
+ }
- monitor_request = json_object_create();
- columns = json_array_create_empty();
- for (i = 0; i < tc->n_columns; i++) {
- const struct ovsdb_idl_column *column = &tc->columns[i];
- json_array_add(columns, json_string_create(column->name));
+ if (columns) {
+ monitor_request = json_object_create();
+ json_object_put(monitor_request, "columns", columns);
+ json_object_put(monitor_requests, tc->name, monitor_request);
}
- json_object_put(monitor_request, "columns", columns);
- json_object_put(monitor_requests, tc->name, monitor_request);
}
json_destroy(idl->monitor_request_id);
msg = jsonrpc_create_request(
- "monitor", json_array_create_2(json_null_create(), monitor_requests),
+ "monitor",
+ json_array_create_3(json_string_create(idl->class->database),
+ json_null_create(), monitor_requests),
&idl->monitor_request_id);
jsonrpc_session_send(idl->session, msg);
}
static void
ovsdb_idl_parse_update(struct ovsdb_idl *idl, const struct json *table_updates)
{
- struct ovsdb_error *error;
-
- idl->change_seqno++;
-
- error = ovsdb_idl_parse_update__(idl, table_updates);
+ struct ovsdb_error *error = ovsdb_idl_parse_update__(idl, table_updates);
if (error) {
if (!VLOG_DROP_WARN(&syntax_rl)) {
char *s = ovsdb_error_to_string(error);
"and \"new\" members");
}
- ovsdb_idl_process_update(table, &uuid, old_json, new_json);
+ if (ovsdb_idl_process_update(table, &uuid, old_json, new_json)) {
+ idl->change_seqno++;
+ }
}
}
{
struct ovsdb_idl_row *row;
- HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, hmap_node,
- uuid_hash(uuid), &table->rows) {
+ HMAP_FOR_EACH_WITH_HASH (row, hmap_node, uuid_hash(uuid), &table->rows) {
if (uuid_equals(&row->uuid, uuid)) {
return row;
}
return NULL;
}
-static void
+/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false
+ * otherwise. */
+static bool
ovsdb_idl_process_update(struct ovsdb_idl_table *table,
const struct uuid *uuid, const struct json *old,
const struct json *new)
VLOG_WARN_RL(&semantic_rl, "cannot delete missing row "UUID_FMT" "
"from table %s",
UUID_ARGS(uuid), table->class->name);
+ return false;
}
} else if (!old) {
/* Insert row. */
} else {
VLOG_WARN_RL(&semantic_rl, "cannot add existing row "UUID_FMT" to "
"table %s", UUID_ARGS(uuid), table->class->name);
- ovsdb_idl_modify_row(row, new);
+ return ovsdb_idl_modify_row(row, new);
}
} else {
/* Modify row. */
if (row) {
/* XXX perhaps we should check the 'old' values? */
if (!ovsdb_idl_row_is_orphan(row)) {
- ovsdb_idl_modify_row(row, new);
+ return ovsdb_idl_modify_row(row, new);
} else {
VLOG_WARN_RL(&semantic_rl, "cannot modify missing but "
"referenced row "UUID_FMT" in table %s",
ovsdb_idl_insert_row(ovsdb_idl_row_create(table, uuid), new);
}
}
+
+ return true;
}
-static void
+/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false
+ * otherwise. */
+static bool
ovsdb_idl_row_update(struct ovsdb_idl_row *row, const struct json *row_json)
{
struct ovsdb_idl_table *table = row->table;
struct shash_node *node;
+ bool changed = false;
SHASH_FOR_EACH (node, json_object(row_json)) {
const char *column_name = node->name;
error = ovsdb_datum_from_json(&datum, &column->type, node->data, NULL);
if (!error) {
- ovsdb_datum_swap(&row->old[column - table->class->columns],
- &datum);
+ unsigned int column_idx = column - table->class->columns;
+ struct ovsdb_datum *old = &row->old[column_idx];
+
+ if (!ovsdb_datum_equals(old, &datum, &column->type)) {
+ ovsdb_datum_swap(old, &datum);
+ if (table->modes[column_idx] & OVSDB_IDL_ALERT) {
+ changed = true;
+ }
+ } else {
+ /* Didn't really change but the OVSDB monitor protocol always
+ * includes every value in a row. */
+ }
+
ovsdb_datum_destroy(&datum, &column->type);
} else {
char *s = ovsdb_error_to_string(error);
ovsdb_error_destroy(error);
}
}
+ return changed;
}
+/* When a row A refers to row B through a column with a "refTable" constraint,
+ * but row B does not exist, row B is called an "orphan row". Orphan rows
+ * should not persist, because the database enforces referential integrity, but
+ * they can appear transiently as changes from the database are received (the
+ * database doesn't try to topologically sort them and circular references mean
+ * it isn't always possible anyhow).
+ *
+ * This function returns true if 'row' is an orphan row, otherwise false.
+ */
static bool
ovsdb_idl_row_is_orphan(const struct ovsdb_idl_row *row)
{
- return !row->old;
+ return !row->old && !row->new;
+}
+
+/* Returns true if 'row' is conceptually part of the database as modified by
+ * the current transaction (if any), false otherwise.
+ *
+ * This function will return true if 'row' is not an orphan (see the comment on
+ * ovsdb_idl_row_is_orphan()) and:
+ *
+ * - 'row' exists in the database and has not been deleted within the
+ * current transaction (if any).
+ *
+ * - 'row' was inserted within the current transaction and has not been
+ * deleted. (In the latter case you should not have passed 'row' in at
+ * all, because ovsdb_idl_txn_delete() freed it.)
+ *
+ * This function will return false if 'row' is an orphan or if 'row' was
+ * deleted within the current transaction.
+ */
+static bool
+ovsdb_idl_row_exists(const struct ovsdb_idl_row *row)
+{
+ return row->new != NULL;
+}
+
+static void
+ovsdb_idl_row_parse(struct ovsdb_idl_row *row)
+{
+ const struct ovsdb_idl_table_class *class = row->table->class;
+ size_t i;
+
+ for (i = 0; i < class->n_columns; i++) {
+ const struct ovsdb_idl_column *c = &class->columns[i];
+ (c->parse)(row, &row->old[i]);
+ }
+}
+
+static void
+ovsdb_idl_row_unparse(struct ovsdb_idl_row *row)
+{
+ const struct ovsdb_idl_table_class *class = row->table->class;
+ size_t i;
+
+ for (i = 0; i < class->n_columns; i++) {
+ const struct ovsdb_idl_column *c = &class->columns[i];
+ (c->unparse)(row);
+ }
}
static void
ovsdb_idl_row_clear_old(struct ovsdb_idl_row *row)
{
- assert(row->old == row->new);
+ ovs_assert(row->old == row->new);
if (!ovsdb_idl_row_is_orphan(row)) {
const struct ovsdb_idl_table_class *class = row->table->class;
size_t i;
const struct ovsdb_idl_table_class *class = row->table->class;
size_t i;
- BITMAP_FOR_EACH_1 (i, class->n_columns, row->written) {
- ovsdb_datum_destroy(&row->new[i], &class->columns[i].type);
+ if (row->written) {
+ BITMAP_FOR_EACH_1 (i, class->n_columns, row->written) {
+ ovsdb_datum_destroy(&row->new[i], &class->columns[i].type);
+ }
}
free(row->new);
free(row->written);
/* Delete all forward arcs. If 'destroy_dsts', destroy any orphaned rows
* that this causes to be unreferenced. */
- LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, src_node,
- &row->src_arcs) {
+ LIST_FOR_EACH_SAFE (arc, next, src_node, &row->src_arcs) {
list_remove(&arc->dst_node);
if (destroy_dsts
&& ovsdb_idl_row_is_orphan(arc->dst)
/* Force nodes that reference 'row' to reparse. */
static void
-ovsdb_idl_row_reparse_backrefs(struct ovsdb_idl_row *row, bool destroy_dsts)
+ovsdb_idl_row_reparse_backrefs(struct ovsdb_idl_row *row)
{
struct ovsdb_idl_arc *arc, *next;
/* This is trickier than it looks. ovsdb_idl_row_clear_arcs() will destroy
* 'arc', so we need to use the "safe" variant of list traversal. However,
- * calling ref->table->class->parse will add an arc equivalent to 'arc' to
- * row->arcs. That could be a problem for traversal, but it adds it at the
- * beginning of the list to prevent us from stumbling upon it again.
+ * calling an ovsdb_idl_column's 'parse' function will add an arc
+ * equivalent to 'arc' to row->arcs. That could be a problem for
+ * traversal, but it adds it at the beginning of the list to prevent us
+ * from stumbling upon it again.
*
* (If duplicate arcs were possible then we would need to make sure that
* 'next' didn't also point into 'arc''s destination, but we forbid
* duplicate arcs.) */
- LIST_FOR_EACH_SAFE (arc, next, struct ovsdb_idl_arc, dst_node,
- &row->dst_arcs) {
+ LIST_FOR_EACH_SAFE (arc, next, dst_node, &row->dst_arcs) {
struct ovsdb_idl_row *ref = arc->src;
- (ref->table->class->unparse)(ref);
- ovsdb_idl_row_clear_arcs(ref, destroy_dsts);
- (ref->table->class->parse)(ref);
+ ovsdb_idl_row_unparse(ref);
+ ovsdb_idl_row_clear_arcs(ref, false);
+ ovsdb_idl_row_parse(ref);
}
}
ovsdb_idl_row_create__(const struct ovsdb_idl_table_class *class)
{
struct ovsdb_idl_row *row = xzalloc(class->allocation_size);
+ class->row_init(row);
list_init(&row->src_arcs);
list_init(&row->dst_arcs);
hmap_node_nullify(&row->txn_node);
const struct ovsdb_idl_table_class *class = row->table->class;
size_t i;
- assert(!row->old && !row->new);
+ ovs_assert(!row->old && !row->new);
row->old = row->new = xmalloc(class->n_columns * sizeof *row->old);
for (i = 0; i < class->n_columns; i++) {
ovsdb_datum_init_default(&row->old[i], &class->columns[i].type);
}
ovsdb_idl_row_update(row, row_json);
- (class->parse)(row);
+ ovsdb_idl_row_parse(row);
- ovsdb_idl_row_reparse_backrefs(row, false);
+ ovsdb_idl_row_reparse_backrefs(row);
}
static void
ovsdb_idl_delete_row(struct ovsdb_idl_row *row)
{
- (row->table->class->unparse)(row);
+ ovsdb_idl_row_unparse(row);
ovsdb_idl_row_clear_arcs(row, true);
ovsdb_idl_row_clear_old(row);
if (list_is_empty(&row->dst_arcs)) {
ovsdb_idl_row_destroy(row);
} else {
- ovsdb_idl_row_reparse_backrefs(row, true);
+ ovsdb_idl_row_reparse_backrefs(row);
}
}
-static void
+/* Returns true if a column with mode OVSDB_IDL_MODE_RW changed, false
+ * otherwise. */
+static bool
ovsdb_idl_modify_row(struct ovsdb_idl_row *row, const struct json *row_json)
{
- (row->table->class->unparse)(row);
+ bool changed;
+
+ ovsdb_idl_row_unparse(row);
ovsdb_idl_row_clear_arcs(row, true);
- ovsdb_idl_row_update(row, row_json);
- (row->table->class->parse)(row);
+ changed = ovsdb_idl_row_update(row, row_json);
+ ovsdb_idl_row_parse(row);
+
+ return changed;
}
static bool
*
* We only need to test whether the first arc in dst->dst_arcs originates
* at 'src', since we add all of the arcs from a given source in a clump
- * (in a single call to a row's ->parse function) and new arcs are always
+ * (in a single call to ovsdb_idl_row_parse()) and new arcs are always
* added at the front of the dst_arcs list. */
if (list_is_empty(&dst->dst_arcs)) {
return true;
return &idl->tables[table_class - idl->class->tables];
}
+/* Called by ovsdb-idlc generated code. */
struct ovsdb_idl_row *
ovsdb_idl_get_row_arc(struct ovsdb_idl_row *src,
struct ovsdb_idl_table_class *dst_table_class,
dst_table = ovsdb_idl_table_from_class(idl, dst_table_class);
dst = ovsdb_idl_get_row(dst_table, dst_uuid);
- if (!dst) {
- dst = ovsdb_idl_row_create(dst_table, dst_uuid);
- }
+ if (idl->txn) {
+ /* We're being called from ovsdb_idl_txn_write(). We must not update
+ * any arcs, because the transaction will be backed out at commit or
+ * abort time and we don't want our graph screwed up.
+ *
+ * Just return the destination row, if there is one and it has not been
+ * deleted. */
+ if (dst && (hmap_node_is_null(&dst->txn_node) || dst->new)) {
+ return dst;
+ }
+ return NULL;
+ } else {
+ /* We're being called from some other context. Update the graph. */
+ if (!dst) {
+ dst = ovsdb_idl_row_create(dst_table, dst_uuid);
+ }
- /* Add a new arc, if it wouldn't be a self-arc or a duplicate arc. */
- if (may_add_arc(src, dst)) {
- /* The arc *must* be added at the front of the dst_arcs list. See
- * ovsdb_idl_row_reparse_backrefs() for details. */
- arc = xmalloc(sizeof *arc);
- list_push_front(&src->src_arcs, &arc->src_node);
- list_push_front(&dst->dst_arcs, &arc->dst_node);
- arc->src = src;
- arc->dst = dst;
+ /* Add a new arc, if it wouldn't be a self-arc or a duplicate arc. */
+ if (may_add_arc(src, dst)) {
+ /* The arc *must* be added at the front of the dst_arcs list. See
+ * ovsdb_idl_row_reparse_backrefs() for details. */
+ arc = xmalloc(sizeof *arc);
+ list_push_front(&src->src_arcs, &arc->src_node);
+ list_push_front(&dst->dst_arcs, &arc->dst_node);
+ arc->src = src;
+ arc->dst = dst;
+ }
+
+ return !ovsdb_idl_row_is_orphan(dst) ? dst : NULL;
}
+}
- return !ovsdb_idl_row_is_orphan(dst) ? dst : NULL;
+/* Searches 'tc''s table in 'idl' for a row with UUID 'uuid'. Returns a
+ * pointer to the row if there is one, otherwise a null pointer. */
+const struct ovsdb_idl_row *
+ovsdb_idl_get_row_for_uuid(const struct ovsdb_idl *idl,
+ const struct ovsdb_idl_table_class *tc,
+ const struct uuid *uuid)
+{
+ return ovsdb_idl_get_row(ovsdb_idl_table_from_class(idl, tc), uuid);
}
static struct ovsdb_idl_row *
struct ovsdb_idl_row *row;
row = CONTAINER_OF(node, struct ovsdb_idl_row, hmap_node);
- if (!ovsdb_idl_row_is_orphan(row)) {
+ if (ovsdb_idl_row_exists(row)) {
return row;
}
}
return NULL;
}
-struct ovsdb_idl_row *
+/* Returns a row in 'table_class''s table in 'idl', or a null pointer if that
+ * table is empty.
+ *
+ * Database tables are internally maintained as hash tables, so adding or
+ * removing rows while traversing the same table can cause some rows to be
+ * visited twice or not at apply. */
+const struct ovsdb_idl_row *
ovsdb_idl_first_row(const struct ovsdb_idl *idl,
const struct ovsdb_idl_table_class *table_class)
{
return next_real_row(table, hmap_first(&table->rows));
}
-struct ovsdb_idl_row *
+/* Returns a row following 'row' within its table, or a null pointer if 'row'
+ * is the last row in its table. */
+const struct ovsdb_idl_row *
ovsdb_idl_next_row(const struct ovsdb_idl_row *row)
{
struct ovsdb_idl_table *table = row->table;
return next_real_row(table, hmap_next(&table->rows, &row->hmap_node));
}
+
+/* Reads and returns the value of 'column' within 'row'. If an ongoing
+ * transaction has changed 'column''s value, the modified value is returned.
+ *
+ * The caller must not modify or free the returned value.
+ *
+ * Various kinds of changes can invalidate the returned value: writing to the
+ * same 'column' in 'row' (e.g. with ovsdb_idl_txn_write()), deleting 'row'
+ * (e.g. with ovsdb_idl_txn_delete()), or completing an ongoing transaction
+ * (e.g. with ovsdb_idl_txn_commit() or ovsdb_idl_txn_abort()). If the
+ * returned value is needed for a long time, it is best to make a copy of it
+ * with ovsdb_datum_clone(). */
+const struct ovsdb_datum *
+ovsdb_idl_read(const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column)
+{
+ const struct ovsdb_idl_table_class *class;
+ size_t column_idx;
+
+ ovs_assert(!ovsdb_idl_row_is_synthetic(row));
+
+ class = row->table->class;
+ column_idx = column - class->columns;
+
+ ovs_assert(row->new != NULL);
+ ovs_assert(column_idx < class->n_columns);
+
+ if (row->written && bitmap_is_set(row->written, column_idx)) {
+ return &row->new[column_idx];
+ } else if (row->old) {
+ return &row->old[column_idx];
+ } else {
+ return ovsdb_datum_default(&column->type);
+ }
+}
+
+/* Same as ovsdb_idl_read(), except that it also asserts that 'column' has key
+ * type 'key_type' and value type 'value_type'. (Scalar and set types will
+ * have a value type of OVSDB_TYPE_VOID.)
+ *
+ * This is useful in code that "knows" that a particular column has a given
+ * type, so that it will abort if someone changes the column's type without
+ * updating the code that uses it. */
+const struct ovsdb_datum *
+ovsdb_idl_get(const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column,
+ enum ovsdb_atomic_type key_type OVS_UNUSED,
+ enum ovsdb_atomic_type value_type OVS_UNUSED)
+{
+ ovs_assert(column->type.key.type == key_type);
+ ovs_assert(column->type.value.type == value_type);
+
+ return ovsdb_idl_read(row, column);
+}
+
+/* Returns false if 'row' was obtained from the IDL, true if it was initialized
+ * to all-zero-bits by some other entity. If 'row' was set up some other way
+ * then the return value is indeterminate. */
+bool
+ovsdb_idl_row_is_synthetic(const struct ovsdb_idl_row *row)
+{
+ return row->table == NULL;
+}
\f
/* Transactions. */
static void ovsdb_idl_txn_complete(struct ovsdb_idl_txn *txn,
enum ovsdb_idl_txn_status);
+/* Returns a string representation of 'status'. The caller must not modify or
+ * free the returned string.
+ *
+ * The return value is probably useful only for debug log messages and unit
+ * tests. */
const char *
ovsdb_idl_txn_status_to_string(enum ovsdb_idl_txn_status status)
{
switch (status) {
+ case TXN_UNCOMMITTED:
+ return "uncommitted";
case TXN_UNCHANGED:
return "unchanged";
case TXN_INCOMPLETE:
return "success";
case TXN_TRY_AGAIN:
return "try again";
+ case TXN_NOT_LOCKED:
+ return "not locked";
case TXN_ERROR:
return "error";
}
return "<unknown>";
}
+/* Starts a new transaction on 'idl'. A given ovsdb_idl may only have a single
+ * active transaction at a time. See the large comment in ovsdb-idl.h for
+ * general information on transactions. */
struct ovsdb_idl_txn *
ovsdb_idl_txn_create(struct ovsdb_idl *idl)
{
struct ovsdb_idl_txn *txn;
- assert(!idl->txn);
+ ovs_assert(!idl->txn);
idl->txn = txn = xmalloc(sizeof *txn);
+ txn->request_id = NULL;
txn->idl = idl;
- txn->status = TXN_INCOMPLETE;
hmap_init(&txn->txn_rows);
+ txn->status = TXN_UNCOMMITTED;
+ txn->error = NULL;
txn->dry_run = false;
ds_init(&txn->comment);
+
txn->inc_table = NULL;
txn->inc_column = NULL;
- txn->inc_where = NULL;
+
+ hmap_init(&txn->inserted_rows);
+
return txn;
}
+/* Appends 's', which is treated as a printf()-type format string, to the
+ * comments that will be passed to the OVSDB server when 'txn' is committed.
+ * (The comment will be committed to the OVSDB log, which "ovsdb-tool
+ * show-log" can print in a relatively human-readable form.) */
void
-ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *txn, const char *s)
+ovsdb_idl_txn_add_comment(struct ovsdb_idl_txn *txn, const char *s, ...)
{
+ va_list args;
+
if (txn->comment.length) {
ds_put_char(&txn->comment, '\n');
}
- ds_put_cstr(&txn->comment, s);
+
+ va_start(args, s);
+ ds_put_format_valist(&txn->comment, s, args);
+ va_end(args);
}
+/* Marks 'txn' as a transaction that will not actually modify the database. In
+ * almost every way, the transaction is treated like other transactions. It
+ * must be committed or aborted like other transactions, it will be sent to the
+ * database server like other transactions, and so on. The only difference is
+ * that the operations sent to the database server will include, as the last
+ * step, an "abort" operation, so that any changes made by the transaction will
+ * not actually take effect. */
void
ovsdb_idl_txn_set_dry_run(struct ovsdb_idl_txn *txn)
{
txn->dry_run = true;
}
+/* Causes 'txn', when committed, to increment the value of 'column' within
+ * 'row' by 1. 'column' must have an integer type. After 'txn' commits
+ * successfully, the client may retrieve the final (incremented) value of
+ * 'column' with ovsdb_idl_txn_get_increment_new_value().
+ *
+ * The client could accomplish something similar with ovsdb_idl_read(),
+ * ovsdb_idl_txn_verify() and ovsdb_idl_txn_write(), or with ovsdb-idlc
+ * generated wrappers for these functions. However, ovsdb_idl_txn_increment()
+ * will never (by itself) fail because of a verify error.
+ *
+ * The intended use is for incrementing the "next_cfg" column in the
+ * Open_vSwitch table. */
void
-ovsdb_idl_txn_increment(struct ovsdb_idl_txn *txn, const char *table,
- const char *column, const struct json *where)
+ovsdb_idl_txn_increment(struct ovsdb_idl_txn *txn,
+ const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column)
{
- assert(!txn->inc_table);
- txn->inc_table = xstrdup(table);
- txn->inc_column = xstrdup(column);
- txn->inc_where = where ? json_clone(where) : json_array_create_empty();
+ ovs_assert(!txn->inc_table);
+ ovs_assert(column->type.key.type == OVSDB_TYPE_INTEGER);
+ ovs_assert(column->type.value.type == OVSDB_TYPE_VOID);
+
+ txn->inc_table = row->table->class->name;
+ txn->inc_column = column->name;
+ txn->inc_row = row->uuid;
}
+/* Destroys 'txn' and frees all associated memory. If ovsdb_idl_txn_commit()
+ * has been called for 'txn' but the commit is still incomplete (that is, the
+ * last call returned TXN_INCOMPLETE) then the transaction may or may not still
+ * end up committing at the database server, but the client will not be able to
+ * get any further status information back. */
void
ovsdb_idl_txn_destroy(struct ovsdb_idl_txn *txn)
{
+ struct ovsdb_idl_txn_insert *insert, *next;
+
+ json_destroy(txn->request_id);
if (txn->status == TXN_INCOMPLETE) {
hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node);
}
ovsdb_idl_txn_abort(txn);
ds_destroy(&txn->comment);
- free(txn->inc_table);
- free(txn->inc_column);
- json_destroy(txn->inc_where);
+ free(txn->error);
+ HMAP_FOR_EACH_SAFE (insert, next, hmap_node, &txn->inserted_rows) {
+ free(insert);
+ }
+ hmap_destroy(&txn->inserted_rows);
free(txn);
}
+/* Causes poll_block() to wake up if 'txn' has completed committing. */
void
ovsdb_idl_txn_wait(const struct ovsdb_idl_txn *txn)
{
- if (txn->status != TXN_INCOMPLETE) {
+ if (txn->status != TXN_UNCOMMITTED && txn->status != TXN_INCOMPLETE) {
poll_immediate_wake();
}
}
{
const struct ovsdb_idl_row *row;
- HMAP_FOR_EACH_WITH_HASH (row, struct ovsdb_idl_row, txn_node,
- uuid_hash(uuid), &txn->txn_rows) {
+ HMAP_FOR_EACH_WITH_HASH (row, txn_node, uuid_hash(uuid), &txn->txn_rows) {
if (uuid_equals(&row->uuid, uuid)) {
return row;
}
{
struct ovsdb_idl_row *row, *next;
- HMAP_FOR_EACH_SAFE (row, next, struct ovsdb_idl_row, txn_node,
- &txn->txn_rows) {
- if (row->old && row->written) {
- (row->table->class->unparse)(row);
- ovsdb_idl_row_clear_arcs(row, false);
- (row->table->class->parse)(row);
+ /* This must happen early. Otherwise, ovsdb_idl_row_parse() will call an
+ * ovsdb_idl_column's 'parse' function, which will call
+ * ovsdb_idl_get_row_arc(), which will seen that the IDL is in a
+ * transaction and fail to update the graph. */
+ txn->idl->txn = NULL;
+
+ HMAP_FOR_EACH_SAFE (row, next, txn_node, &txn->txn_rows) {
+ if (row->old) {
+ if (row->written) {
+ ovsdb_idl_row_unparse(row);
+ ovsdb_idl_row_clear_arcs(row, false);
+ ovsdb_idl_row_parse(row);
+ }
+ } else {
+ ovsdb_idl_row_unparse(row);
}
ovsdb_idl_row_clear_new(row);
hmap_remove(&txn->txn_rows, &row->txn_node);
hmap_node_nullify(&row->txn_node);
+ if (!row->old) {
+ hmap_remove(&row->table->rows, &row->hmap_node);
+ free(row);
+ }
}
hmap_destroy(&txn->txn_rows);
hmap_init(&txn->txn_rows);
}
+/* Attempts to commit 'txn'. Returns the status of the commit operation, one
+ * of the following TXN_* constants:
+ *
+ * TXN_INCOMPLETE:
+ *
+ * The transaction is in progress, but not yet complete. The caller
+ * should call again later, after calling ovsdb_idl_run() to let the IDL
+ * do OVSDB protocol processing.
+ *
+ * TXN_UNCHANGED:
+ *
+ * The transaction is complete. (It didn't actually change the database,
+ * so the IDL didn't send any request to the database server.)
+ *
+ * TXN_ABORTED:
+ *
+ * The caller previously called ovsdb_idl_txn_abort().
+ *
+ * TXN_SUCCESS:
+ *
+ * The transaction was successful. The update made by the transaction
+ * (and possibly other changes made by other database clients) should
+ * already be visible in the IDL.
+ *
+ * TXN_TRY_AGAIN:
+ *
+ * The transaction failed for some transient reason, e.g. because a
+ * "verify" operation reported an inconsistency or due to a network
+ * problem. The caller should wait for a change to the database, then
+ * compose a new transaction, and commit the new transaction.
+ *
+ * Use the return value of ovsdb_idl_get_seqno() to wait for a change in
+ * the database. It is important to use its return value *before* the
+ * initial call to ovsdb_idl_txn_commit() as the baseline for this
+ * purpose, because the change that one should wait for can happen after
+ * the initial call but before the call that returns TXN_TRY_AGAIN, and
+ * using some other baseline value in that situation could cause an
+ * indefinite wait if the database rarely changes.
+ *
+ * TXN_NOT_LOCKED:
+ *
+ * The transaction failed because the IDL has been configured to require
+ * a database lock (with ovsdb_idl_set_lock()) but didn't get it yet or
+ * has already lost it.
+ *
+ * Committing a transaction rolls back all of the changes that it made to the
+ * IDL's copy of the database. If the transaction commits successfully, then
+ * the database server will send an update and, thus, the IDL will be updated
+ * with the committed changes. */
enum ovsdb_idl_txn_status
ovsdb_idl_txn_commit(struct ovsdb_idl_txn *txn)
{
return txn->status;
}
- operations = json_array_create_empty();
+ /* If we need a lock but don't have it, give up quickly. */
+ if (txn->idl->lock_name && !ovsdb_idl_has_lock(txn->idl)) {
+ txn->status = TXN_NOT_LOCKED;
+ ovsdb_idl_txn_disassemble(txn);
+ return txn->status;
+ }
+
+ operations = json_array_create_1(
+ json_string_create(txn->idl->class->database));
+
+ /* Assert that we have the required lock (avoiding a race). */
+ if (txn->idl->lock_name) {
+ struct json *op = json_object_create();
+ json_array_add(operations, op);
+ json_object_put_string(op, "op", "assert");
+ json_object_put_string(op, "lock", txn->idl->lock_name);
+ }
/* Add prerequisites and declarations of new rows. */
- HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) {
+ HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) {
/* XXX check that deleted rows exist even if no prereqs? */
if (row->prereqs) {
const struct ovsdb_idl_table_class *class = row->table->class;
&column->type));
}
}
- if (row->new && !row->old) {
- struct json *op;
-
- op = json_object_create();
- json_array_add(operations, op);
- json_object_put_string(op, "op", "declare");
- json_object_put(op, "uuid-name",
- json_string_create_nocopy(
- uuid_name_from_uuid(&row->uuid)));
- }
}
/* Add updates. */
any_updates = false;
- HMAP_FOR_EACH (row, struct ovsdb_idl_row, txn_node, &txn->txn_rows) {
+ HMAP_FOR_EACH (row, txn_node, &txn->txn_rows) {
const struct ovsdb_idl_table_class *class = row->table->class;
- if (row->old == row->new) {
- continue;
- } else if (!row->new) {
- struct json *op = json_object_create();
- json_object_put_string(op, "op", "delete");
- json_object_put_string(op, "table", class->name);
- json_object_put(op, "where", where_uuid_equals(&row->uuid));
- json_array_add(operations, op);
- any_updates = true;
- } else {
+ if (!row->new) {
+ if (class->is_root) {
+ struct json *op = json_object_create();
+ json_object_put_string(op, "op", "delete");
+ json_object_put_string(op, "table", class->name);
+ json_object_put(op, "where", where_uuid_equals(&row->uuid));
+ json_array_add(operations, op);
+ any_updates = true;
+ } else {
+ /* Let ovsdb-server decide whether to really delete it. */
+ }
+ } else if (row->old != row->new) {
struct json *row_json;
struct json *op;
size_t idx;
if (row->old) {
json_object_put(op, "where", where_uuid_equals(&row->uuid));
} else {
+ struct ovsdb_idl_txn_insert *insert;
+
+ any_updates = true;
+
json_object_put(op, "uuid-name",
json_string_create_nocopy(
uuid_name_from_uuid(&row->uuid)));
+
+ insert = xmalloc(sizeof *insert);
+ insert->dummy = row->uuid;
+ insert->op_index = operations->u.array.n - 1;
+ uuid_zero(&insert->real);
+ hmap_insert(&txn->inserted_rows, &insert->hmap_node,
+ uuid_hash(&insert->dummy));
}
row_json = json_object_create();
json_object_put(op, "row", row_json);
- BITMAP_FOR_EACH_1 (idx, class->n_columns, row->written) {
- const struct ovsdb_idl_column *column = &class->columns[idx];
-
- if (!row->old || !ovsdb_datum_equals(&row->old[idx],
- &row->new[idx],
- &column->type)) {
- json_object_put(row_json, column->name,
- substitute_uuids(
- ovsdb_datum_to_json(&row->new[idx],
- &column->type),
- txn));
+ if (row->written) {
+ BITMAP_FOR_EACH_1 (idx, class->n_columns, row->written) {
+ const struct ovsdb_idl_column *column =
+ &class->columns[idx];
+
+ if (row->old
+ || !ovsdb_datum_is_default(&row->new[idx],
+ &column->type)) {
+ json_object_put(row_json, column->name,
+ substitute_uuids(
+ ovsdb_datum_to_json(&row->new[idx],
+ &column->type),
+ txn));
+
+ /* If anything really changed, consider it an update.
+ * We can't suppress not-really-changed values earlier
+ * or transactions would become nonatomic (see the big
+ * comment inside ovsdb_idl_txn_write()). */
+ if (!any_updates && row->old &&
+ !ovsdb_datum_equals(&row->old[idx], &row->new[idx],
+ &column->type)) {
+ any_updates = true;
+ }
+ }
}
}
if (!row->old || !shash_is_empty(json_object(row_json))) {
json_array_add(operations, op);
- any_updates = true;
} else {
json_destroy(op);
}
if (txn->inc_table && any_updates) {
struct json *op;
- txn->inc_index = operations->u.array.n;
+ txn->inc_index = operations->u.array.n - 1;
op = json_object_create();
json_object_put_string(op, "op", "mutate");
json_object_put_string(op, "table", txn->inc_table);
json_object_put(op, "where",
- substitute_uuids(json_clone(txn->inc_where), txn));
+ substitute_uuids(where_uuid_equals(&txn->inc_row),
+ txn));
json_object_put(op, "mutations",
json_array_create_1(
json_array_create_3(
json_object_put_string(op, "op", "select");
json_object_put_string(op, "table", txn->inc_table);
json_object_put(op, "where",
- substitute_uuids(json_clone(txn->inc_where), txn));
+ substitute_uuids(where_uuid_equals(&txn->inc_row),
+ txn));
json_object_put(op, "columns",
json_array_create_1(json_string_create(
txn->inc_column)));
"transact", operations, &txn->request_id))) {
hmap_insert(&txn->idl->outstanding_txns, &txn->hmap_node,
json_hash(txn->request_id, 0));
- } else {
txn->status = TXN_INCOMPLETE;
+ } else {
+ txn->status = TXN_TRY_AGAIN;
}
- txn->idl->txn = NULL;
ovsdb_idl_txn_disassemble(txn);
return txn->status;
}
+/* Attempts to commit 'txn', blocking until the commit either succeeds or
+ * fails. Returns the final commit status, which may be any TXN_* value other
+ * than TXN_INCOMPLETE.
+ *
+ * This function calls ovsdb_idl_run() on 'txn''s IDL, so it may cause the
+ * return value of ovsdb_idl_get_seqno() to change. */
+enum ovsdb_idl_txn_status
+ovsdb_idl_txn_commit_block(struct ovsdb_idl_txn *txn)
+{
+ enum ovsdb_idl_txn_status status;
+
+ fatal_signal_run();
+ while ((status = ovsdb_idl_txn_commit(txn)) == TXN_INCOMPLETE) {
+ ovsdb_idl_run(txn->idl);
+ ovsdb_idl_wait(txn->idl);
+ ovsdb_idl_txn_wait(txn);
+ poll_block();
+ }
+ return status;
+}
+
+/* Returns the final (incremented) value of the column in 'txn' that was set to
+ * be incremented by ovsdb_idl_txn_increment(). 'txn' must have committed
+ * successfully. */
int64_t
ovsdb_idl_txn_get_increment_new_value(const struct ovsdb_idl_txn *txn)
{
- assert(txn->status == TXN_SUCCESS);
+ ovs_assert(txn->status == TXN_SUCCESS);
return txn->inc_new_value;
}
+/* Aborts 'txn' without sending it to the database server. This is effective
+ * only if ovsdb_idl_txn_commit() has not yet been called for 'txn'.
+ * Otherwise, it has no effect.
+ *
+ * Aborting a transaction doesn't free its memory. Use
+ * ovsdb_idl_txn_destroy() to do that. */
void
ovsdb_idl_txn_abort(struct ovsdb_idl_txn *txn)
{
ovsdb_idl_txn_disassemble(txn);
- if (txn->status == TXN_INCOMPLETE) {
+ if (txn->status == TXN_UNCOMMITTED || txn->status == TXN_INCOMPLETE) {
txn->status = TXN_ABORTED;
}
}
+/* Returns a string that reports the error status for 'txn'. The caller must
+ * not modify or free the returned string. A call to ovsdb_idl_txn_destroy()
+ * for 'txn' may free the returned string.
+ *
+ * The return value is ordinarily one of the strings that
+ * ovsdb_idl_txn_status_to_string() would return, but if the transaction failed
+ * due to an error reported by the database server, the return value is that
+ * error. */
+const char *
+ovsdb_idl_txn_get_error(const struct ovsdb_idl_txn *txn)
+{
+ if (txn->status != TXN_ERROR) {
+ return ovsdb_idl_txn_status_to_string(txn->status);
+ } else if (txn->error) {
+ return txn->error;
+ } else {
+ return "no error details available";
+ }
+}
+
+static void
+ovsdb_idl_txn_set_error_json(struct ovsdb_idl_txn *txn,
+ const struct json *json)
+{
+ if (txn->error == NULL) {
+ txn->error = json_to_string(json, JSSF_SORT);
+ }
+}
+
+/* For transaction 'txn' that completed successfully, finds and returns the
+ * permanent UUID that the database assigned to a newly inserted row, given the
+ * 'uuid' that ovsdb_idl_txn_insert() assigned locally to that row.
+ *
+ * Returns NULL if 'uuid' is not a UUID assigned by ovsdb_idl_txn_insert() or
+ * if it was assigned by that function and then deleted by
+ * ovsdb_idl_txn_delete() within the same transaction. (Rows that are inserted
+ * and then deleted within a single transaction are never sent to the database
+ * server, so it never assigns them a permanent UUID.) */
+const struct uuid *
+ovsdb_idl_txn_get_insert_uuid(const struct ovsdb_idl_txn *txn,
+ const struct uuid *uuid)
+{
+ const struct ovsdb_idl_txn_insert *insert;
+
+ ovs_assert(txn->status == TXN_SUCCESS || txn->status == TXN_UNCHANGED);
+ HMAP_FOR_EACH_IN_BUCKET (insert, hmap_node,
+ uuid_hash(uuid), &txn->inserted_rows) {
+ if (uuid_equals(uuid, &insert->dummy)) {
+ return &insert->real;
+ }
+ }
+ return NULL;
+}
+
static void
ovsdb_idl_txn_complete(struct ovsdb_idl_txn *txn,
enum ovsdb_idl_txn_status status)
hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node);
}
-void
-ovsdb_idl_txn_write(struct ovsdb_idl_row *row,
- const struct ovsdb_idl_column *column,
- struct ovsdb_datum *datum)
+/* Writes 'datum' to the specified 'column' in 'row_'. Updates both 'row_'
+ * itself and the structs derived from it (e.g. the "struct ovsrec_*", for
+ * ovs-vswitchd).
+ *
+ * 'datum' must have the correct type for its column. The IDL does not check
+ * that it meets schema constraints, but ovsdb-server will do so at commit time
+ * so it had better be correct.
+ *
+ * A transaction must be in progress. Replication of 'column' must not have
+ * been disabled (by calling ovsdb_idl_omit()).
+ *
+ * Usually this function is used indirectly through one of the "set" functions
+ * generated by ovsdb-idlc.
+ *
+ * Takes ownership of what 'datum' points to (and in some cases destroys that
+ * data before returning) but makes a copy of 'datum' itself. (Commonly
+ * 'datum' is on the caller's stack.) */
+static void
+ovsdb_idl_txn_write__(const struct ovsdb_idl_row *row_,
+ const struct ovsdb_idl_column *column,
+ struct ovsdb_datum *datum, bool owns_datum)
{
- const struct ovsdb_idl_table_class *class = row->table->class;
- size_t column_idx = column - class->columns;
+ struct ovsdb_idl_row *row = CONST_CAST(struct ovsdb_idl_row *, row_);
+ const struct ovsdb_idl_table_class *class;
+ size_t column_idx;
+ bool write_only;
+
+ if (ovsdb_idl_row_is_synthetic(row)) {
+ goto discard_datum;
+ }
+
+ class = row->table->class;
+ column_idx = column - class->columns;
+ write_only = row->table->modes[column_idx] == OVSDB_IDL_MONITOR;
+
+ ovs_assert(row->new != NULL);
+ ovs_assert(column_idx < class->n_columns);
+ ovs_assert(row->old == NULL ||
+ row->table->modes[column_idx] & OVSDB_IDL_MONITOR);
+
+ if (row->table->idl->verify_write_only && !write_only) {
+ VLOG_ERR("Bug: Attempt to write to a read/write column (%s:%s) when"
+ " explicitly configured not to.", class->name, column->name);
+ goto discard_datum;
+ }
+
+ /* If this is a write-only column and the datum being written is the same
+ * as the one already there, just skip the update entirely. This is worth
+ * optimizing because we have a lot of columns that get periodically
+ * refreshed into the database but don't actually change that often.
+ *
+ * We don't do this for read/write columns because that would break
+ * atomicity of transactions--some other client might have written a
+ * different value in that column since we read it. (But if a whole
+ * transaction only does writes of existing values, without making any real
+ * changes, we will drop the whole transaction later in
+ * ovsdb_idl_txn_commit().) */
+ if (write_only && ovsdb_datum_equals(ovsdb_idl_read(row, column),
+ datum, &column->type)) {
+ goto discard_datum;
+ }
- assert(row->new);
if (hmap_node_is_null(&row->txn_node)) {
hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node,
uuid_hash(&row->uuid));
} else {
bitmap_set1(row->written, column_idx);
}
- row->new[column_idx] = *datum;
+ if (owns_datum) {
+ row->new[column_idx] = *datum;
+ } else {
+ ovsdb_datum_clone(&row->new[column_idx], datum, &column->type);
+ }
+ (column->unparse)(row);
+ (column->parse)(row, &row->new[column_idx]);
+ return;
+
+discard_datum:
+ if (owns_datum) {
+ ovsdb_datum_destroy(datum, &column->type);
+ }
+}
+
+void
+ovsdb_idl_txn_write(const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column,
+ struct ovsdb_datum *datum)
+{
+ ovsdb_idl_txn_write__(row, column, datum, true);
}
+void
+ovsdb_idl_txn_write_clone(const struct ovsdb_idl_row *row,
+ const struct ovsdb_idl_column *column,
+ const struct ovsdb_datum *datum)
+{
+ ovsdb_idl_txn_write__(row, column,
+ CONST_CAST(struct ovsdb_datum *, datum), false);
+}
+
+/* Causes the original contents of 'column' in 'row_' to be verified as a
+ * prerequisite to completing the transaction. That is, if 'column' in 'row_'
+ * changed (or if 'row_' was deleted) between the time that the IDL originally
+ * read its contents and the time that the transaction commits, then the
+ * transaction aborts and ovsdb_idl_txn_commit() returns TXN_AGAIN_WAIT or
+ * TXN_AGAIN_NOW (depending on whether the database change has already been
+ * received).
+ *
+ * The intention is that, to ensure that no transaction commits based on dirty
+ * reads, an application should call ovsdb_idl_txn_verify() on each data item
+ * read as part of a read-modify-write operation.
+ *
+ * In some cases ovsdb_idl_txn_verify() reduces to a no-op, because the current
+ * value of 'column' is already known:
+ *
+ * - If 'row_' is a row created by the current transaction (returned by
+ * ovsdb_idl_txn_insert()).
+ *
+ * - If 'column' has already been modified (with ovsdb_idl_txn_write())
+ * within the current transaction.
+ *
+ * Because of the latter property, always call ovsdb_idl_txn_verify() *before*
+ * ovsdb_idl_txn_write() for a given read-modify-write.
+ *
+ * A transaction must be in progress.
+ *
+ * Usually this function is used indirectly through one of the "verify"
+ * functions generated by ovsdb-idlc. */
void
ovsdb_idl_txn_verify(const struct ovsdb_idl_row *row_,
const struct ovsdb_idl_column *column)
{
- struct ovsdb_idl_row *row = (struct ovsdb_idl_row *) row_;
- const struct ovsdb_idl_table_class *class = row->table->class;
- size_t column_idx = column - class->columns;
+ struct ovsdb_idl_row *row = CONST_CAST(struct ovsdb_idl_row *, row_);
+ const struct ovsdb_idl_table_class *class;
+ size_t column_idx;
+
+ if (ovsdb_idl_row_is_synthetic(row)) {
+ return;
+ }
- assert(row->new);
+ class = row->table->class;
+ column_idx = column - class->columns;
+
+ ovs_assert(row->new != NULL);
+ ovs_assert(row->old == NULL ||
+ row->table->modes[column_idx] & OVSDB_IDL_MONITOR);
if (!row->old
|| (row->written && bitmap_is_set(row->written, column_idx))) {
return;
bitmap_set1(row->prereqs, column_idx);
}
+/* Deletes 'row_' from its table. May free 'row_', so it must not be
+ * accessed afterward.
+ *
+ * A transaction must be in progress.
+ *
+ * Usually this function is used indirectly through one of the "delete"
+ * functions generated by ovsdb-idlc. */
void
-ovsdb_idl_txn_delete(struct ovsdb_idl_row *row)
+ovsdb_idl_txn_delete(const struct ovsdb_idl_row *row_)
{
- assert(row->new);
+ struct ovsdb_idl_row *row = CONST_CAST(struct ovsdb_idl_row *, row_);
+
+ if (ovsdb_idl_row_is_synthetic(row)) {
+ return;
+ }
+
+ ovs_assert(row->new != NULL);
if (!row->old) {
+ ovsdb_idl_row_unparse(row);
ovsdb_idl_row_clear_new(row);
- assert(!row->prereqs);
+ ovs_assert(!row->prereqs);
+ hmap_remove(&row->table->rows, &row->hmap_node);
hmap_remove(&row->table->idl->txn->txn_rows, &row->txn_node);
free(row);
return;
row->new = NULL;
}
-struct ovsdb_idl_row *
+/* Inserts and returns a new row in the table with the specified 'class' in the
+ * database with open transaction 'txn'.
+ *
+ * The new row is assigned a provisional UUID. If 'uuid' is null then one is
+ * randomly generated; otherwise 'uuid' should specify a randomly generated
+ * UUID not otherwise in use. ovsdb-server will assign a different UUID when
+ * 'txn' is committed, but the IDL will replace any uses of the provisional
+ * UUID in the data to be to be committed by the UUID assigned by
+ * ovsdb-server.
+ *
+ * Usually this function is used indirectly through one of the "insert"
+ * functions generated by ovsdb-idlc. */
+const struct ovsdb_idl_row *
ovsdb_idl_txn_insert(struct ovsdb_idl_txn *txn,
- const struct ovsdb_idl_table_class *class)
+ const struct ovsdb_idl_table_class *class,
+ const struct uuid *uuid)
{
struct ovsdb_idl_row *row = ovsdb_idl_row_create__(class);
- uuid_generate(&row->uuid);
+
+ if (uuid) {
+ ovs_assert(!ovsdb_idl_txn_get_row(txn, uuid));
+ row->uuid = *uuid;
+ } else {
+ uuid_generate(&row->uuid);
+ }
+
row->table = ovsdb_idl_table_from_class(txn->idl, class);
row->new = xmalloc(class->n_columns * sizeof *row->new);
- row->written = bitmap_allocate(class->n_columns);
+ hmap_insert(&row->table->rows, &row->hmap_node, uuid_hash(&row->uuid));
hmap_insert(&txn->txn_rows, &row->txn_node, uuid_hash(&row->uuid));
return row;
}
{
struct ovsdb_idl_txn *txn;
- HMAP_FOR_EACH (txn, struct ovsdb_idl_txn, hmap_node,
- &idl->outstanding_txns) {
+ HMAP_FOR_EACH (txn, hmap_node, &idl->outstanding_txns) {
ovsdb_idl_txn_complete(txn, TXN_TRY_AGAIN);
}
}
{
struct ovsdb_idl_txn *txn;
- HMAP_FOR_EACH_WITH_HASH (txn, struct ovsdb_idl_txn, hmap_node,
+ HMAP_FOR_EACH_WITH_HASH (txn, hmap_node,
json_hash(id, 0), &idl->outstanding_txns) {
if (json_equal(id, txn->request_id)) {
return txn;
if (txn->inc_index + 2 > results->n) {
VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations "
- "for increment (has %u, needs %u)",
+ "for increment (has %"PRIuSIZE", needs %u)",
results->n, txn->inc_index + 2);
return false;
}
- /* We know that this is a JSON objects because the loop in
+ /* We know that this is a JSON object because the loop in
* ovsdb_idl_txn_process_reply() checked. */
mutate = json_object(results->elems[txn->inc_index]);
count = shash_find_data(mutate, "count");
}
if (count->u.integer != 1) {
VLOG_WARN_RL(&syntax_rl,
- "\"mutate\" reply \"count\" is %"PRId64" instead of 1",
+ "\"mutate\" reply \"count\" is %lld instead of 1",
count->u.integer);
return false;
}
return false;
}
if (rows->u.array.n != 1) {
- VLOG_WARN_RL(&syntax_rl, "\"select\" reply \"rows\" has %u elements "
+ VLOG_WARN_RL(&syntax_rl, "\"select\" reply \"rows\" has %"PRIuSIZE" elements "
"instead of 1",
rows->u.array.n);
return false;
return true;
}
+static bool
+ovsdb_idl_txn_process_insert_reply(struct ovsdb_idl_txn_insert *insert,
+ const struct json_array *results)
+{
+ static const struct ovsdb_base_type uuid_type = OVSDB_BASE_UUID_INIT;
+ struct ovsdb_error *error;
+ struct json *json_uuid;
+ union ovsdb_atom uuid;
+ struct shash *reply;
+
+ if (insert->op_index >= results->n) {
+ VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations "
+ "for insert (has %"PRIuSIZE", needs %u)",
+ results->n, insert->op_index);
+ return false;
+ }
+
+ /* We know that this is a JSON object because the loop in
+ * ovsdb_idl_txn_process_reply() checked. */
+ reply = json_object(results->elems[insert->op_index]);
+ json_uuid = shash_find_data(reply, "uuid");
+ if (!check_json_type(json_uuid, JSON_ARRAY, "\"insert\" reply \"uuid\"")) {
+ return false;
+ }
+
+ error = ovsdb_atom_from_json(&uuid, &uuid_type, json_uuid, NULL);
+ if (error) {
+ char *s = ovsdb_error_to_string(error);
+ VLOG_WARN_RL(&syntax_rl, "\"insert\" reply \"uuid\" is not a JSON "
+ "UUID: %s", s);
+ free(s);
+ ovsdb_error_destroy(error);
+ return false;
+ }
+
+ insert->real = uuid.uuid;
+
+ return true;
+}
static bool
ovsdb_idl_txn_process_reply(struct ovsdb_idl *idl,
VLOG_WARN_RL(&syntax_rl, "reply to \"transact\" is not JSON array");
status = TXN_ERROR;
} else {
+ struct json_array *ops = &msg->result->u.array;
int hard_errors = 0;
int soft_errors = 0;
+ int lock_errors = 0;
size_t i;
- for (i = 0; i < msg->result->u.array.n; i++) {
- struct json *json = msg->result->u.array.elems[i];
+ for (i = 0; i < ops->n; i++) {
+ struct json *op = ops->elems[i];
- if (json->type == JSON_NULL) {
+ if (op->type == JSON_NULL) {
/* This isn't an error in itself but indicates that some prior
* operation failed, so make sure that we know about it. */
soft_errors++;
- } else if (json->type == JSON_OBJECT) {
+ } else if (op->type == JSON_OBJECT) {
struct json *error;
- error = shash_find_data(json_object(json), "error");
+ error = shash_find_data(json_object(op), "error");
if (error) {
if (error->type == JSON_STRING) {
if (!strcmp(error->u.string, "timed out")) {
soft_errors++;
+ } else if (!strcmp(error->u.string, "not owner")) {
+ lock_errors++;
} else if (strcmp(error->u.string, "aborted")) {
hard_errors++;
+ ovsdb_idl_txn_set_error_json(txn, op);
}
} else {
hard_errors++;
+ ovsdb_idl_txn_set_error_json(txn, op);
VLOG_WARN_RL(&syntax_rl,
"\"error\" in reply is not JSON string");
}
}
} else {
hard_errors++;
+ ovsdb_idl_txn_set_error_json(txn, op);
VLOG_WARN_RL(&syntax_rl,
"operation reply is not JSON null or object");
}
}
- if (txn->inc_table
- && !soft_errors
- && !hard_errors
- && !ovsdb_idl_txn_process_inc_reply(txn,
- json_array(msg->result))) {
- hard_errors++;
+ if (!soft_errors && !hard_errors && !lock_errors) {
+ struct ovsdb_idl_txn_insert *insert;
+
+ if (txn->inc_table && !ovsdb_idl_txn_process_inc_reply(txn, ops)) {
+ hard_errors++;
+ }
+
+ HMAP_FOR_EACH (insert, hmap_node, &txn->inserted_rows) {
+ if (!ovsdb_idl_txn_process_insert_reply(insert, ops)) {
+ hard_errors++;
+ }
+ }
}
status = (hard_errors ? TXN_ERROR
+ : lock_errors ? TXN_NOT_LOCKED
: soft_errors ? TXN_TRY_AGAIN
: TXN_SUCCESS);
}
return true;
}
+/* Returns the transaction currently active for 'row''s IDL. A transaction
+ * must currently be active. */
struct ovsdb_idl_txn *
ovsdb_idl_txn_get(const struct ovsdb_idl_row *row)
{
struct ovsdb_idl_txn *txn = row->table->idl->txn;
- assert(txn != NULL);
+ ovs_assert(txn != NULL);
return txn;
}
+
+/* Returns the IDL on which 'txn' acts. */
+struct ovsdb_idl *
+ovsdb_idl_txn_get_idl (struct ovsdb_idl_txn *txn)
+{
+ return txn->idl;
+}
+\f
+/* If 'lock_name' is nonnull, configures 'idl' to obtain the named lock from
+ * the database server and to avoid modifying the database when the lock cannot
+ * be acquired (that is, when another client has the same lock).
+ *
+ * If 'lock_name' is NULL, drops the locking requirement and releases the
+ * lock. */
+void
+ovsdb_idl_set_lock(struct ovsdb_idl *idl, const char *lock_name)
+{
+ ovs_assert(!idl->txn);
+ ovs_assert(hmap_is_empty(&idl->outstanding_txns));
+
+ if (idl->lock_name && (!lock_name || strcmp(lock_name, idl->lock_name))) {
+ /* Release previous lock. */
+ ovsdb_idl_send_unlock_request(idl);
+ free(idl->lock_name);
+ idl->lock_name = NULL;
+ idl->is_lock_contended = false;
+ }
+
+ if (lock_name && !idl->lock_name) {
+ /* Acquire new lock. */
+ idl->lock_name = xstrdup(lock_name);
+ ovsdb_idl_send_lock_request(idl);
+ }
+}
+
+/* Returns true if 'idl' is configured to obtain a lock and owns that lock.
+ *
+ * Locking and unlocking happens asynchronously from the database client's
+ * point of view, so the information is only useful for optimization (e.g. if
+ * the client doesn't have the lock then there's no point in trying to write to
+ * the database). */
+bool
+ovsdb_idl_has_lock(const struct ovsdb_idl *idl)
+{
+ return idl->has_lock;
+}
+
+/* Returns true if 'idl' is configured to obtain a lock but the database server
+ * has indicated that some other client already owns the requested lock. */
+bool
+ovsdb_idl_is_lock_contended(const struct ovsdb_idl *idl)
+{
+ return idl->is_lock_contended;
+}
+
+static void
+ovsdb_idl_update_has_lock(struct ovsdb_idl *idl, bool new_has_lock)
+{
+ if (new_has_lock && !idl->has_lock) {
+ if (!idl->monitor_request_id) {
+ idl->change_seqno++;
+ } else {
+ /* We're waiting for a monitor reply, so don't signal that the
+ * database changed. The monitor reply will increment change_seqno
+ * anyhow. */
+ }
+ idl->is_lock_contended = false;
+ }
+ idl->has_lock = new_has_lock;
+}
+
+static void
+ovsdb_idl_send_lock_request__(struct ovsdb_idl *idl, const char *method,
+ struct json **idp)
+{
+ ovsdb_idl_update_has_lock(idl, false);
+
+ json_destroy(idl->lock_request_id);
+ idl->lock_request_id = NULL;
+
+ if (jsonrpc_session_is_connected(idl->session)) {
+ struct json *params;
+
+ params = json_array_create_1(json_string_create(idl->lock_name));
+ jsonrpc_session_send(idl->session,
+ jsonrpc_create_request(method, params, idp));
+ }
+}
+
+static void
+ovsdb_idl_send_lock_request(struct ovsdb_idl *idl)
+{
+ ovsdb_idl_send_lock_request__(idl, "lock", &idl->lock_request_id);
+}
+
+static void
+ovsdb_idl_send_unlock_request(struct ovsdb_idl *idl)
+{
+ ovsdb_idl_send_lock_request__(idl, "unlock", NULL);
+}
+
+static void
+ovsdb_idl_parse_lock_reply(struct ovsdb_idl *idl, const struct json *result)
+{
+ bool got_lock;
+
+ json_destroy(idl->lock_request_id);
+ idl->lock_request_id = NULL;
+
+ if (result->type == JSON_OBJECT) {
+ const struct json *locked;
+
+ locked = shash_find_data(json_object(result), "locked");
+ got_lock = locked && locked->type == JSON_TRUE;
+ } else {
+ got_lock = false;
+ }
+
+ ovsdb_idl_update_has_lock(idl, got_lock);
+ if (!got_lock) {
+ idl->is_lock_contended = true;
+ }
+}
+
+static void
+ovsdb_idl_parse_lock_notify(struct ovsdb_idl *idl,
+ const struct json *params,
+ bool new_has_lock)
+{
+ if (idl->lock_name
+ && params->type == JSON_ARRAY
+ && json_array(params)->n > 0
+ && json_array(params)->elems[0]->type == JSON_STRING) {
+ const char *lock_name = json_string(json_array(params)->elems[0]);
+
+ if (!strcmp(idl->lock_name, lock_name)) {
+ ovsdb_idl_update_has_lock(idl, new_has_lock);
+ if (!new_has_lock) {
+ idl->is_lock_contended = true;
+ }
+ }
+ }
+}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff