diff options
Diffstat (limited to 'src/lib-sql/driver-sqlpool.c')
| -rw-r--r-- | src/lib-sql/driver-sqlpool.c | 934 |
1 files changed, 934 insertions, 0 deletions
diff --git a/src/lib-sql/driver-sqlpool.c b/src/lib-sql/driver-sqlpool.c new file mode 100644 index 0000000..553b2a0 --- /dev/null +++ b/src/lib-sql/driver-sqlpool.c @@ -0,0 +1,934 @@ +/* Copyright (c) 2010-2018 Dovecot authors, see the included COPYING file */ + +#include "lib.h" +#include "array.h" +#include "llist.h" +#include "ioloop.h" +#include "sql-api-private.h" + +#include <time.h> + +#define QUERY_TIMEOUT_SECS 6 + +/* sqlpool events are separate from category:sql, because + they are usually not very interesting, and would only + make logging too noisy. They can be enabled explicitly. +*/ +static struct event_category event_category_sqlpool = { + .name = "sqlpool", +}; + +struct sqlpool_host { + char *connect_string; + + unsigned int connection_count; +}; + +struct sqlpool_connection { + struct sql_db *db; + unsigned int host_idx; +}; + +struct sqlpool_db { + struct sql_db api; + + pool_t pool; + const struct sql_db *driver; + unsigned int connection_limit; + + ARRAY(struct sqlpool_host) hosts; + /* all connections from all hosts */ + ARRAY(struct sqlpool_connection) all_connections; + /* index of last connection in all_connections that was used to + send a query. */ + unsigned int last_query_conn_idx; + + /* queued requests */ + struct sqlpool_request *requests_head, *requests_tail; + struct timeout *request_to; +}; + +struct sqlpool_request { + struct sqlpool_request *prev, *next; + + struct sqlpool_db *db; + time_t created; + + unsigned int host_idx; + unsigned int retry_count; + + struct event *event; + + /* requests are a) queries */ + char *query; + sql_query_callback_t *callback; + void *context; + + /* b) transaction waiters */ + struct sqlpool_transaction_context *trans; +}; + +struct sqlpool_transaction_context { + struct sql_transaction_context ctx; + + sql_commit_callback_t *callback; + void *context; + + pool_t query_pool; + struct sqlpool_request *commit_request; +}; + +extern struct sql_db driver_sqlpool_db; + +static struct sqlpool_connection * +sqlpool_add_connection(struct sqlpool_db *db, struct sqlpool_host *host, + unsigned int host_idx); +static void +driver_sqlpool_query_callback(struct sql_result *result, + struct sqlpool_request *request); +static void +driver_sqlpool_commit_callback(const struct sql_commit_result *result, + struct sqlpool_transaction_context *ctx); +static void driver_sqlpool_deinit(struct sql_db *_db); + +static struct sqlpool_request * ATTR_NULL(2) +sqlpool_request_new(struct sqlpool_db *db, const char *query) +{ + struct sqlpool_request *request; + + request = i_new(struct sqlpool_request, 1); + request->db = db; + request->created = time(NULL); + request->query = i_strdup(query); + request->event = event_create(db->api.event); + return request; +} + +static void +sqlpool_request_free(struct sqlpool_request **_request) +{ + struct sqlpool_request *request = *_request; + + *_request = NULL; + + i_assert(request->prev == NULL && request->next == NULL); + event_unref(&request->event); + i_free(request->query); + i_free(request); +} + +static void +sqlpool_request_abort(struct sqlpool_request **_request) +{ + struct sqlpool_request *request = *_request; + + *_request = NULL; + + if (request->callback != NULL) + request->callback(&sql_not_connected_result, request->context); + + i_assert(request->prev != NULL || + request->db->requests_head == request); + DLLIST2_REMOVE(&request->db->requests_head, + &request->db->requests_tail, request); + sqlpool_request_free(&request); +} + +static struct sql_transaction_context * +driver_sqlpool_new_conn_trans(struct sqlpool_transaction_context *trans, + struct sql_db *conndb) +{ + struct sql_transaction_context *conn_trans; + struct sql_transaction_query *query; + + conn_trans = sql_transaction_begin(conndb); + /* backend will use our queries list (we might still append more + queries to the list) */ + conn_trans->head = trans->ctx.head; + conn_trans->tail = trans->ctx.tail; + for (query = conn_trans->head; query != NULL; query = query->next) + query->trans = conn_trans; + return conn_trans; +} + +static void +sqlpool_request_handle_transaction(struct sql_db *conndb, + struct sqlpool_transaction_context *trans) +{ + struct sql_transaction_context *conn_trans; + + sqlpool_request_free(&trans->commit_request); + conn_trans = driver_sqlpool_new_conn_trans(trans, conndb); + sql_transaction_commit(&conn_trans, + driver_sqlpool_commit_callback, trans); +} + +static void +sqlpool_request_send_next(struct sqlpool_db *db, struct sql_db *conndb) +{ + struct sqlpool_request *request; + + if (db->requests_head == NULL || !SQL_DB_IS_READY(conndb)) + return; + + request = db->requests_head; + DLLIST2_REMOVE(&db->requests_head, &db->requests_tail, request); + timeout_reset(db->request_to); + + if (request->query != NULL) { + sql_query(conndb, request->query, + driver_sqlpool_query_callback, request); + } else if (request->trans != NULL) { + sqlpool_request_handle_transaction(conndb, request->trans); + } else { + i_unreached(); + } +} + +static void sqlpool_reconnect(struct sql_db *conndb) +{ + timeout_remove(&conndb->to_reconnect); + (void)sql_connect(conndb); +} + +static struct sqlpool_host * +sqlpool_find_host_with_least_connections(struct sqlpool_db *db, + unsigned int *host_idx_r) +{ + struct sqlpool_host *hosts, *min = NULL; + unsigned int i, count; + + hosts = array_get_modifiable(&db->hosts, &count); + i_assert(count > 0); + + min = &hosts[0]; + *host_idx_r = 0; + + for (i = 1; i < count; i++) { + if (min->connection_count > hosts[i].connection_count) { + min = &hosts[i]; + *host_idx_r = i; + } + } + return min; +} + +static bool sqlpool_have_successful_connections(struct sqlpool_db *db) +{ + const struct sqlpool_connection *conn; + + array_foreach(&db->all_connections, conn) { + if (conn->db->state >= SQL_DB_STATE_IDLE) + return TRUE; + } + return FALSE; +} + +static void +sqlpool_handle_connect_failed(struct sqlpool_db *db, struct sql_db *conndb) +{ + struct sqlpool_host *host; + unsigned int host_idx; + + if (conndb->connect_failure_count > 0) { + /* increase delay between reconnections to this + server */ + conndb->connect_delay *= 5; + if (conndb->connect_delay > SQL_CONNECT_MAX_DELAY) + conndb->connect_delay = SQL_CONNECT_MAX_DELAY; + } + conndb->connect_failure_count++; + + /* reconnect after the delay */ + timeout_remove(&conndb->to_reconnect); + conndb->to_reconnect = timeout_add(conndb->connect_delay * 1000, + sqlpool_reconnect, conndb); + + /* if we have zero successful hosts and there still are hosts + without connections, connect to one of them. */ + if (!sqlpool_have_successful_connections(db)) { + host = sqlpool_find_host_with_least_connections(db, &host_idx); + if (host->connection_count == 0) + (void)sqlpool_add_connection(db, host, host_idx); + } +} + +static void +sqlpool_state_changed(struct sql_db *conndb, enum sql_db_state prev_state, + void *context) +{ + struct sqlpool_db *db = context; + + if (conndb->state == SQL_DB_STATE_IDLE) { + conndb->connect_failure_count = 0; + conndb->connect_delay = SQL_CONNECT_MIN_DELAY; + sqlpool_request_send_next(db, conndb); + } + + if (prev_state == SQL_DB_STATE_CONNECTING && + conndb->state == SQL_DB_STATE_DISCONNECTED && + !conndb->no_reconnect) + sqlpool_handle_connect_failed(db, conndb); +} + +static struct sqlpool_connection * +sqlpool_add_connection(struct sqlpool_db *db, struct sqlpool_host *host, + unsigned int host_idx) +{ + struct sql_db *conndb; + struct sqlpool_connection *conn; + const char *error; + int ret = 0; + + host->connection_count++; + + e_debug(db->api.event, "Creating new connection"); + + if (db->driver->v.init_full == NULL) { + conndb = db->driver->v.init(host->connect_string); + } else { + struct sql_settings set = { + .connect_string = host->connect_string, + .event_parent = event_get_parent(db->api.event), + }; + ret = db->driver->v.init_full(&set, &conndb, &error); + } + if (ret < 0) + i_fatal("sqlpool: %s", error); + + sql_init_common(conndb); + + conndb->state_change_callback = sqlpool_state_changed; + conndb->state_change_context = db; + conndb->connect_delay = SQL_CONNECT_MIN_DELAY; + + conn = array_append_space(&db->all_connections); + conn->host_idx = host_idx; + conn->db = conndb; + return conn; +} + +static struct sqlpool_connection * +sqlpool_add_new_connection(struct sqlpool_db *db) +{ + struct sqlpool_host *host; + unsigned int host_idx; + + host = sqlpool_find_host_with_least_connections(db, &host_idx); + if (host->connection_count >= db->connection_limit) + return NULL; + else + return sqlpool_add_connection(db, host, host_idx); +} + +static const struct sqlpool_connection * +sqlpool_find_available_connection(struct sqlpool_db *db, + unsigned int unwanted_host_idx, + bool *all_disconnected_r) +{ + const struct sqlpool_connection *conns; + unsigned int i, count; + + *all_disconnected_r = TRUE; + + conns = array_get(&db->all_connections, &count); + for (i = 0; i < count; i++) { + unsigned int idx = (i + db->last_query_conn_idx + 1) % count; + struct sql_db *conndb = conns[idx].db; + + if (conns[idx].host_idx == unwanted_host_idx) + continue; + + if (!SQL_DB_IS_READY(conndb) && conndb->to_reconnect == NULL) { + /* see if we could reconnect to it immediately */ + (void)sql_connect(conndb); + } + if (SQL_DB_IS_READY(conndb)) { + db->last_query_conn_idx = idx; + *all_disconnected_r = FALSE; + return &conns[idx]; + } + if (conndb->state != SQL_DB_STATE_DISCONNECTED) + *all_disconnected_r = FALSE; + } + return NULL; +} + +static bool +driver_sqlpool_get_connection(struct sqlpool_db *db, + unsigned int unwanted_host_idx, + const struct sqlpool_connection **conn_r) +{ + const struct sqlpool_connection *conn, *conns; + unsigned int i, count; + bool all_disconnected; + + conn = sqlpool_find_available_connection(db, unwanted_host_idx, + &all_disconnected); + if (conn == NULL && unwanted_host_idx != UINT_MAX) { + /* maybe there are no wanted hosts. use any of them. */ + conn = sqlpool_find_available_connection(db, UINT_MAX, + &all_disconnected); + } + if (conn == NULL && all_disconnected) { + /* no connected connections. connect_delays may have gotten too + high, reset all of them to see if some are still alive. */ + conns = array_get(&db->all_connections, &count); + for (i = 0; i < count; i++) { + struct sql_db *conndb = conns[i].db; + + if (conndb->connect_delay > SQL_CONNECT_RESET_DELAY) + conndb->connect_delay = SQL_CONNECT_RESET_DELAY; + } + conn = sqlpool_find_available_connection(db, UINT_MAX, + &all_disconnected); + } + if (conn == NULL) { + /* still nothing. try creating new connections */ + conn = sqlpool_add_new_connection(db); + if (conn != NULL) + (void)sql_connect(conn->db); + if (conn == NULL || !SQL_DB_IS_READY(conn->db)) + return FALSE; + } + *conn_r = conn; + return TRUE; +} + +static bool +driver_sqlpool_get_sync_connection(struct sqlpool_db *db, + const struct sqlpool_connection **conn_r) +{ + const struct sqlpool_connection *conns; + unsigned int i, count; + + if (driver_sqlpool_get_connection(db, UINT_MAX, conn_r)) + return TRUE; + + /* no idling connections, but maybe we can find one that's trying to + connect to server, and we can use it once it's finished */ + conns = array_get(&db->all_connections, &count); + for (i = 0; i < count; i++) { + if (conns[i].db->state == SQL_DB_STATE_CONNECTING) { + *conn_r = &conns[i]; + return TRUE; + } + } + return FALSE; +} + +static bool +driver_sqlpool_get_connected_flags(struct sqlpool_db *db, + enum sql_db_flags *flags_r) +{ + const struct sqlpool_connection *conn; + + array_foreach(&db->all_connections, conn) { + if (conn->db->state > SQL_DB_STATE_CONNECTING) { + *flags_r = sql_get_flags(conn->db); + return TRUE; + } + } + return FALSE; +} + +static enum sql_db_flags driver_sqlpool_get_flags(struct sql_db *_db) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conn; + enum sql_db_flags flags; + + /* try to use a connected db */ + if (driver_sqlpool_get_connected_flags(db, &flags)) + return flags; + + if (!driver_sqlpool_get_sync_connection(db, &conn)) { + /* Failed to connect to database. Just use the first + connection. */ + conn = array_idx(&db->all_connections, 0); + } + return sql_get_flags(conn->db); +} + +static int +driver_sqlpool_parse_hosts(struct sqlpool_db *db, const char *connect_string, + const char **error_r) +{ + const char *const *args, *key, *value, *hostname; + struct sqlpool_host *host; + ARRAY_TYPE(const_string) hostnames, connect_args; + + t_array_init(&hostnames, 8); + t_array_init(&connect_args, 32); + + /* connect string is a space separated list. it may contain + backend-specific strings which we'll pass as-is. we'll only care + about our own settings, plus the host settings. */ + args = t_strsplit_spaces(connect_string, " "); + for (; *args != NULL; args++) { + value = strchr(*args, '='); + if (value == NULL) { + key = *args; + value = ""; + } else { + key = t_strdup_until(*args, value); + value++; + } + + if (strcmp(key, "maxconns") == 0) { + if (str_to_uint(value, &db->connection_limit) < 0) { + *error_r = t_strdup_printf("Invalid value for maxconns: %s", + value); + return -1; + } + } else if (strcmp(key, "host") == 0) { + array_push_back(&hostnames, &value); + } else { + array_push_back(&connect_args, args); + } + } + + /* build a new connect string without our settings or hosts */ + array_append_zero(&connect_args); + connect_string = t_strarray_join(array_front(&connect_args), " "); + + if (array_count(&hostnames) == 0) { + /* no hosts specified. create a default one. */ + host = array_append_space(&db->hosts); + host->connect_string = i_strdup(connect_string); + } else { + if (*connect_string == '\0') + connect_string = NULL; + + array_foreach_elem(&hostnames, hostname) { + host = array_append_space(&db->hosts); + host->connect_string = + i_strconcat("host=", hostname, " ", + connect_string, NULL); + } + } + + if (db->connection_limit == 0) + db->connection_limit = SQL_DEFAULT_CONNECTION_LIMIT; + return 0; +} + +static void sqlpool_add_all_once(struct sqlpool_db *db) +{ + struct sqlpool_host *host; + unsigned int host_idx; + + for (;;) { + host = sqlpool_find_host_with_least_connections(db, &host_idx); + if (host->connection_count > 0) + break; + (void)sqlpool_add_connection(db, host, host_idx); + } +} + +int driver_sqlpool_init_full(const struct sql_settings *set, const struct sql_db *driver, + struct sql_db **db_r, const char **error_r) +{ + struct sqlpool_db *db; + int ret; + + db = i_new(struct sqlpool_db, 1); + db->driver = driver; + db->api = driver_sqlpool_db; + db->api.flags = driver->flags; + db->api.event = event_create(set->event_parent); + event_add_category(db->api.event, &event_category_sqlpool); + event_set_append_log_prefix(db->api.event, + t_strdup_printf("sqlpool(%s): ", driver->name)); + i_array_init(&db->hosts, 8); + + T_BEGIN { + ret = driver_sqlpool_parse_hosts(db, set->connect_string, + error_r); + } T_END_PASS_STR_IF(ret < 0, error_r); + + if (ret < 0) { + driver_sqlpool_deinit(&db->api); + return ret; + } + i_array_init(&db->all_connections, 16); + /* connect to all databases so we can do load balancing immediately */ + sqlpool_add_all_once(db); + + *db_r = &db->api; + return 0; +} + +static void driver_sqlpool_abort_requests(struct sqlpool_db *db) +{ + while (db->requests_head != NULL) { + struct sqlpool_request *request = db->requests_head; + + sqlpool_request_abort(&request); + } + timeout_remove(&db->request_to); +} + +static void driver_sqlpool_deinit(struct sql_db *_db) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + struct sqlpool_host *host; + struct sqlpool_connection *conn; + + array_foreach_modifiable(&db->all_connections, conn) + sql_unref(&conn->db); + array_clear(&db->all_connections); + + driver_sqlpool_abort_requests(db); + + array_foreach_modifiable(&db->hosts, host) + i_free(host->connect_string); + + i_assert(array_count(&db->all_connections) == 0); + array_free(&db->hosts); + array_free(&db->all_connections); + array_free(&_db->module_contexts); + event_unref(&_db->event); + i_free(db); +} + +static int driver_sqlpool_connect(struct sql_db *_db) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conn; + int ret = -1, ret2; + + array_foreach(&db->all_connections, conn) { + ret2 = conn->db->to_reconnect != NULL ? -1 : + sql_connect(conn->db); + if (ret2 > 0) + ret = 1; + else if (ret2 == 0 && ret < 0) + ret = 0; + } + return ret; +} + +static void driver_sqlpool_disconnect(struct sql_db *_db) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conn; + + array_foreach(&db->all_connections, conn) + sql_disconnect(conn->db); + driver_sqlpool_abort_requests(db); +} + +static const char * +driver_sqlpool_escape_string(struct sql_db *_db, const char *string) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conns; + unsigned int i, count; + + /* use the first ready connection */ + conns = array_get(&db->all_connections, &count); + for (i = 0; i < count; i++) { + if (SQL_DB_IS_READY(conns[i].db)) + return sql_escape_string(conns[i].db, string); + } + /* no ready connections. just use the first one (we're guaranteed + to always have one) */ + return sql_escape_string(conns[0].db, string); +} + +static void driver_sqlpool_timeout(struct sqlpool_db *db) +{ + int duration; + + while (db->requests_head != NULL) { + struct sqlpool_request *request = db->requests_head; + + if (request->created + SQL_QUERY_TIMEOUT_SECS > ioloop_time) + break; + + + if (request->query != NULL) { + e_error(sql_query_finished_event(&db->api, request->event, + request->query, FALSE, + &duration)-> + add_str("error", "Query timed out")-> + event(), + SQL_QUERY_FINISHED_FMT": Query timed out " + "(no free connections for %u secs)", + request->query, duration, + (unsigned int)(ioloop_time - request->created)); + } else { + e_error(event_create_passthrough(request->event)-> + add_str("error", "Timed out")-> + set_name(SQL_TRANSACTION_FINISHED)->event(), + "Transaction timed out " + "(no free connections for %u secs)", + (unsigned int)(ioloop_time - request->created)); + } + sqlpool_request_abort(&request); + } + + if (db->requests_head == NULL) + timeout_remove(&db->request_to); +} + +static void +driver_sqlpool_prepend_request(struct sqlpool_db *db, + struct sqlpool_request *request) +{ + DLLIST2_PREPEND(&db->requests_head, &db->requests_tail, request); + if (db->request_to == NULL) { + db->request_to = timeout_add(SQL_QUERY_TIMEOUT_SECS * 1000, + driver_sqlpool_timeout, db); + } +} + +static void +driver_sqlpool_append_request(struct sqlpool_db *db, + struct sqlpool_request *request) +{ + DLLIST2_APPEND(&db->requests_head, &db->requests_tail, request); + if (db->request_to == NULL) { + db->request_to = timeout_add(SQL_QUERY_TIMEOUT_SECS * 1000, + driver_sqlpool_timeout, db); + } +} + +static void +driver_sqlpool_query_callback(struct sql_result *result, + struct sqlpool_request *request) +{ + struct sqlpool_db *db = request->db; + const struct sqlpool_connection *conn = NULL; + struct sql_db *conndb; + + if (result->failed_try_retry && + request->retry_count < array_count(&db->hosts)) { + e_warning(db->api.event, "Query failed, retrying: %s", + sql_result_get_error(result)); + request->retry_count++; + driver_sqlpool_prepend_request(db, request); + + if (driver_sqlpool_get_connection(request->db, + request->host_idx, &conn)) { + request->host_idx = conn->host_idx; + sqlpool_request_send_next(db, conn->db); + } + } else { + if (result->failed) { + e_error(db->api.event, "Query failed, aborting: %s", + request->query); + } + conndb = result->db; + + if (request->callback != NULL) + request->callback(result, request->context); + sqlpool_request_free(&request); + + sqlpool_request_send_next(db, conndb); + } +} + +static void ATTR_NULL(3, 4) +driver_sqlpool_query(struct sql_db *_db, const char *query, + sql_query_callback_t *callback, void *context) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + struct sqlpool_request *request; + const struct sqlpool_connection *conn; + + request = sqlpool_request_new(db, query); + request->callback = callback; + request->context = context; + + if (!driver_sqlpool_get_connection(db, UINT_MAX, &conn)) + driver_sqlpool_append_request(db, request); + else { + request->host_idx = conn->host_idx; + sql_query(conn->db, query, driver_sqlpool_query_callback, + request); + } +} + +static void driver_sqlpool_exec(struct sql_db *_db, const char *query) +{ + driver_sqlpool_query(_db, query, NULL, NULL); +} + +static struct sql_result * +driver_sqlpool_query_s(struct sql_db *_db, const char *query) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conn; + struct sql_result *result; + + if (!driver_sqlpool_get_sync_connection(db, &conn)) { + sql_not_connected_result.refcount++; + return &sql_not_connected_result; + } + + result = sql_query_s(conn->db, query); + if (result->failed_try_retry) { + if (!driver_sqlpool_get_sync_connection(db, &conn)) + return result; + + sql_result_unref(result); + result = sql_query_s(conn->db, query); + } + return result; +} + +static struct sql_transaction_context * +driver_sqlpool_transaction_begin(struct sql_db *_db) +{ + struct sqlpool_transaction_context *ctx; + + ctx = i_new(struct sqlpool_transaction_context, 1); + ctx->ctx.db = _db; + + /* queue changes until commit. even if we did have a free connection + now, don't use it or multiple open transactions could tie up all + connections. */ + ctx->query_pool = pool_alloconly_create("sqlpool transaction", 1024); + return &ctx->ctx; +} + +static void +driver_sqlpool_transaction_free(struct sqlpool_transaction_context *ctx) +{ + if (ctx->commit_request != NULL) + sqlpool_request_abort(&ctx->commit_request); + pool_unref(&ctx->query_pool); + i_free(ctx); +} + +static void +driver_sqlpool_commit_callback(const struct sql_commit_result *result, + struct sqlpool_transaction_context *ctx) +{ + ctx->callback(result, ctx->context); + driver_sqlpool_transaction_free(ctx); +} + +static void +driver_sqlpool_transaction_commit(struct sql_transaction_context *_ctx, + sql_commit_callback_t *callback, + void *context) +{ + struct sqlpool_transaction_context *ctx = + (struct sqlpool_transaction_context *)_ctx; + struct sqlpool_db *db = (struct sqlpool_db *)_ctx->db; + const struct sqlpool_connection *conn; + + ctx->callback = callback; + ctx->context = context; + + ctx->commit_request = sqlpool_request_new(db, NULL); + ctx->commit_request->trans = ctx; + + if (driver_sqlpool_get_connection(db, UINT_MAX, &conn)) + sqlpool_request_handle_transaction(conn->db, ctx); + else + driver_sqlpool_append_request(db, ctx->commit_request); +} + +static int +driver_sqlpool_transaction_commit_s(struct sql_transaction_context *_ctx, + const char **error_r) +{ + struct sqlpool_transaction_context *ctx = + (struct sqlpool_transaction_context *)_ctx; + struct sqlpool_db *db = (struct sqlpool_db *)_ctx->db; + const struct sqlpool_connection *conn; + struct sql_transaction_context *conn_trans; + int ret; + + *error_r = NULL; + + if (!driver_sqlpool_get_sync_connection(db, &conn)) { + *error_r = SQL_ERRSTR_NOT_CONNECTED; + driver_sqlpool_transaction_free(ctx); + return -1; + } + + conn_trans = driver_sqlpool_new_conn_trans(ctx, conn->db); + ret = sql_transaction_commit_s(&conn_trans, error_r); + driver_sqlpool_transaction_free(ctx); + return ret; +} + +static void +driver_sqlpool_transaction_rollback(struct sql_transaction_context *_ctx) +{ + struct sqlpool_transaction_context *ctx = + (struct sqlpool_transaction_context *)_ctx; + + driver_sqlpool_transaction_free(ctx); +} + +static void +driver_sqlpool_update(struct sql_transaction_context *_ctx, const char *query, + unsigned int *affected_rows) +{ + struct sqlpool_transaction_context *ctx = + (struct sqlpool_transaction_context *)_ctx; + + /* we didn't get a connection for transaction immediately. + queue updates until commit transfers all of these */ + sql_transaction_add_query(&ctx->ctx, ctx->query_pool, + query, affected_rows); +} + +static const char * +driver_sqlpool_escape_blob(struct sql_db *_db, + const unsigned char *data, size_t size) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conns; + unsigned int i, count; + + /* use the first ready connection */ + conns = array_get(&db->all_connections, &count); + for (i = 0; i < count; i++) { + if (SQL_DB_IS_READY(conns[i].db)) + return sql_escape_blob(conns[i].db, data, size); + } + /* no ready connections. just use the first one (we're guaranteed + to always have one) */ + return sql_escape_blob(conns[0].db, data, size); +} + +static void driver_sqlpool_wait(struct sql_db *_db) +{ + struct sqlpool_db *db = (struct sqlpool_db *)_db; + const struct sqlpool_connection *conn; + + array_foreach(&db->all_connections, conn) + sql_wait(conn->db); +} + +struct sql_db driver_sqlpool_db = { + "", + + .v = { + .get_flags = driver_sqlpool_get_flags, + .deinit = driver_sqlpool_deinit, + .connect = driver_sqlpool_connect, + .disconnect = driver_sqlpool_disconnect, + .escape_string = driver_sqlpool_escape_string, + .exec = driver_sqlpool_exec, + .query = driver_sqlpool_query, + .query_s = driver_sqlpool_query_s, + .wait = driver_sqlpool_wait, + + .transaction_begin = driver_sqlpool_transaction_begin, + .transaction_commit = driver_sqlpool_transaction_commit, + .transaction_commit_s = driver_sqlpool_transaction_commit_s, + .transaction_rollback = driver_sqlpool_transaction_rollback, + + .update = driver_sqlpool_update, + + .escape_blob = driver_sqlpool_escape_blob, + } +}; |