#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).
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__(
static bool ovsdb_idl_txn_process_reply(struct ovsdb_idl *,
const struct jsonrpc_msg *msg);
+/* 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.) */
struct ovsdb_idl *
ovsdb_idl_create(const char *remote, const struct ovsdb_idl_class *class)
{
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, OVSDB_IDL_MODE_RW, tc->n_columns);
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)
{
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);
}
}
-void
+/* Processes a batch of messages from the database server on 'idl'. Returns
+ * true if the database as seen through 'idl' changed, false if it did not
+ * change. The initial fetch of the entire contents of the remote database is
+ * considered to be one kind of change.
+ *
+ * When this function returns false, the client may continue to use any data
+ * structures it obtained from 'idl' in the past. But when it returns true,
+ * the client must not access any of these data structures again, because they
+ * could have freed or reused for other purposes.
+ *
+ * This function can return occasional false positives, that is, report that
+ * the database changed even though it didn't. 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 we already thought
+ * was in the database, but the database server is not supposed to do that.)
+ *
+ * As an alternative to checking the return value, the client may check for
+ * changes in the value returned by ovsdb_idl_get_seqno().
+ */
+bool
ovsdb_idl_run(struct ovsdb_idl *idl)
{
+ unsigned int initial_change_seqno = idl->change_seqno;
int i;
assert(!idl->txn);
} else if (msg->type == JSONRPC_REPLY
&& idl->monitor_request_id
&& json_equal(idl->monitor_request_id, msg->id)) {
+ idl->change_seqno++;
json_destroy(idl->monitor_request_id);
idl->monitor_request_id = NULL;
ovsdb_idl_clear(idl);
}
jsonrpc_msg_destroy(msg);
}
+
+ return initial_change_seqno != idl->change_seqno;
}
+/* 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 number that represents the state of 'idl'. When 'idl' is updated
+ * (by ovsdb_idl_run()), the return value changes. */
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;
}
+/* 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);
}
+
+static void
+ovsdb_idl_set_mode(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column,
+ enum ovsdb_idl_mode mode)
+{
+ size_t i;
+
+ 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]) {
+ unsigned char *modep = &table->modes[column - tc->columns];
+ assert(*modep == OVSDB_IDL_MODE_RW || *modep == mode);
+ *modep = mode;
+ return;
+ }
+ }
+
+ NOT_REACHED();
+}
+
+/* By default, 'idl' replicates all of the columns in the remote database, and
+ * ovsdb_idl_run() returns true upon a change to any column in the database.
+ * Call this function to avoid alerting ovsdb_idl_run()'s caller upon changes
+ * to 'column'.
+ *
+ * This is useful 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.
+ *
+ * The client must be careful not to retain pointers to data in 'column' across
+ * calls to ovsdb_idl_run(), even when that function returns false, because
+ * the client is not alerted to changes.
+ *
+ * This function should be called after ovsdb_idl_create(), but before the
+ * first call to ovsdb_idl_run(). For any given column, this function may be
+ * called or ovsdb_idl_omit() may be called, but not both. */
+void
+ovsdb_idl_set_write_only(struct ovsdb_idl *idl,
+ const struct ovsdb_idl_column *column)
+{
+ ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_WO);
+}
+
+/* By default, 'idl' replicates all of the columns in the remote database.
+ * Call this function to omit replicating 'column'. This saves CPU time and
+ * bandwidth to the database.
+ *
+ * This function should be called after ovsdb_idl_create(), but before the
+ * first call to ovsdb_idl_run(). For any given column, this function may be
+ * called or ovsdb_idl_set_write_only() may be called, but not both. */
+void
+ovsdb_idl_omit(struct ovsdb_idl *idl, const struct ovsdb_idl_column *column)
+{
+ ovsdb_idl_set_mode(idl, column, OVSDB_IDL_MODE_NONE);
+}
\f
static void
ovsdb_idl_send_monitor_request(struct ovsdb_idl *idl)
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 (table->modes[i] != OVSDB_IDL_MODE_NONE) {
+ json_array_add(columns, json_string_create(column->name));
+ }
}
json_object_put(monitor_request, "columns", columns);
json_object_put(monitor_requests, tc->name, monitor_request);
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++;
+ }
}
}
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_MODE_RW) {
+ 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,
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);
}
}
-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)
{
+ bool changed;
+
ovsdb_idl_row_unparse(row);
ovsdb_idl_row_clear_arcs(row, true);
- ovsdb_idl_row_update(row, row_json);
+ changed = ovsdb_idl_row_update(row, row_json);
ovsdb_idl_row_parse(row);
+
+ return changed;
}
static bool
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 = row->table->class;
+ size_t column_idx = column - class->columns;
+
+ assert(row->new != NULL);
+ 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)
+{
+ assert(column->type.key.type == key_type);
+ assert(column->type.value.type == value_type);
+
+ return ovsdb_idl_read(row, column);
+}
\f
/* Transactions. */
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);
}
void
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)
- : !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 (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_equals(&row->old[idx], &row->new[idx],
+ &column->type)
+ : !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));
+ }
}
}
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. */
+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;
+}
+
int64_t
ovsdb_idl_txn_get_increment_new_value(const struct ovsdb_idl_txn *txn)
{
hmap_remove(&txn->idl->outstanding_txns, &txn->hmap_node);
}
-void
-ovsdb_idl_txn_read(const struct ovsdb_idl_row *row,
- const struct ovsdb_idl_column *column,
- struct ovsdb_datum *datum)
-{
- const struct ovsdb_idl_table_class *class = row->table->class;
- size_t column_idx = column - class->columns;
-
- assert(row->new != NULL);
- if (row->written && bitmap_is_set(row->written, column_idx)) {
- ovsdb_datum_clone(datum, &row->new[column_idx], &column->type);
- } else if (row->old) {
- ovsdb_datum_clone(datum, &row->old[column_idx], &column->type);
- } else {
- ovsdb_datum_init_default(datum, &column->type);
- }
-}
-
void
ovsdb_idl_txn_write(const struct ovsdb_idl_row *row_,
const struct ovsdb_idl_column *column,
assert(row->new != NULL);
assert(column_idx < class->n_columns);
+ assert(row->table->modes[column_idx] != OVSDB_IDL_MODE_NONE);
+
if (hmap_node_is_null(&row->txn_node)) {
hmap_insert(&row->table->idl->txn->txn_rows, &row->txn_node,
uuid_hash(&row->uuid));
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) {
+ 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;
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 %zu, needs %u)",
results->n, txn->inc_index + 2);
return false;
}
}
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 %zu elements "
"instead of 1",
rows->u.array.n);
return false;
if (insert->op_index >= results->n) {
VLOG_WARN_RL(&syntax_rl, "reply does not contain enough operations "
- "for insert (has %u, needs %u)",
+ "for insert (has %zu, needs %u)",
results->n, insert->op_index);
return false;
}
assert(txn != NULL);
return txn;
}
+
+struct ovsdb_idl *
+ovsdb_idl_txn_get_idl (struct ovsdb_idl_txn *txn)
+{
+ return txn->idl;
+}
+