terom@21: #define _GNU_SOURCE
terom@21: #include <stdlib.h>
terom@21: #include <assert.h>
terom@21: #include <string.h>
terom@21: 
terom@21: #include "evsql.h"
terom@25: #include "evsql_internal.h"
terom@21: #include "evpq.h"
terom@21: #include "lib/log.h"
terom@21: #include "lib/error.h"
terom@21: #include "lib/misc.h"
terom@21: 
terom@23: 
terom@21: /*
terom@21:  * Actually execute the given query.
terom@21:  *
terom@21:  * The backend should be able to accept the query at this time.
terom@21:  *
terom@25:  * You should assume that if trying to execute a query fails, then the connection should also be considred as failed.
terom@21:  */
terom@25: static int _evsql_query_exec (struct evsql_conn *conn, struct evsql_query *query, const char *command) {
terom@25:     int err;
terom@25: 
terom@25:     switch (conn->evsql->type) {
terom@21:         case EVSQL_EVPQ:
terom@23:             // got params?
terom@23:             if (query->params.count) {
terom@25:                 err = evpq_query_params(conn->engine.evpq, command,
terom@23:                     query->params.count, 
terom@23:                     query->params.types, 
terom@23:                     query->params.values, 
terom@23:                     query->params.lengths, 
terom@23:                     query->params.formats, 
terom@23:                     query->params.result_format
terom@23:                 );
terom@23: 
terom@23:             } else {
terom@23:                 // plain 'ole query
terom@25:                 err = evpq_query(conn->engine.evpq, command);
terom@23:             }
terom@25: 
terom@25:             if (err) {
terom@25:                 if (PQstatus(evpq_pgconn(conn->engine.evpq)) != CONNECTION_OK)
terom@25:                     WARNING("conn failed");
terom@25:                 else
terom@25:                     WARNING("query failed, dropping conn as well");
terom@25:             }
terom@25: 
terom@25:             break;
terom@21:         
terom@21:         default:
terom@21:             FATAL("evsql->type");
terom@21:     }
terom@25: 
terom@25:     if (!err)
terom@25:         // assign the query
terom@25:         conn->query = query;
terom@25: 
terom@25:     return err;
terom@21: }
terom@21: 
terom@21: /*
terom@25:  * Free the query and related resources, doesn't trigger any callbacks or remove from any queues.
terom@25:  *
terom@25:  * The command should already be taken care of (NULL).
terom@23:  */
terom@23: static void _evsql_query_free (struct evsql_query *query) {
terom@23:     assert(query->command == NULL);
terom@23:     
terom@23:     // free params if present
terom@23:     free(query->params.types);
terom@23:     free(query->params.values);
terom@23:     free(query->params.lengths);
terom@23:     free(query->params.formats);
terom@23: 
terom@23:     // free the query itself
terom@23:     free(query);
terom@23: }
terom@23: 
terom@23: /*
terom@25:  * Execute the callback if res is given, and free the query.
terom@21:  */
terom@24: static void _evsql_query_done (struct evsql_query *query, const struct evsql_result_info *res) {
terom@24:     if (res) 
terom@21:         // call the callback
terom@24:         query->cb_fn(res, query->cb_arg);
terom@21:     
terom@21:     // free
terom@23:     _evsql_query_free(query);
terom@21: }
terom@21: 
terom@21: /*
terom@25:  * XXX:
terom@25:  * /
terom@24: static void _evsql_destroy (struct evsql *evsql, const struct evsql_result_info *res) {
terom@21:     struct evsql_query *query;
terom@21:     
terom@21:     // clear the queue
terom@25:     while ((query = TAILQ_FIRST(&evsql->query_queue)) != NULL) {
terom@24:         _evsql_query_done(query, res);
terom@21:         
terom@25:         TAILQ_REMOVE(&evsql->query_queue, query, entry);
terom@21:     }
terom@21:     
terom@21:     // free
terom@21:     free(evsql);
terom@21: }
terom@25: */
terom@21: 
terom@21: /*
terom@25:  * Free the transaction, it should already be deassociated from the query and conn.
terom@21:  */
terom@25: static void _evsql_trans_free (struct evsql_trans *trans) {
terom@25:     // ensure we don't leak anything
terom@25:     assert(trans->query == NULL);
terom@25:     assert(trans->conn == NULL);
terom@21:     
terom@25:     // free
terom@25:     free(trans);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Release a connection. It should already be deassociated from the trans and query.
terom@25:  *
terom@25:  * Releases the engine, removes from the conn_list and frees this.
terom@25:  */
terom@25: static void _evsql_conn_release (struct evsql_conn *conn) {
terom@25:     // ensure we don't leak anything
terom@25:     assert(conn->trans == NULL);
terom@25:     assert(conn->query == NULL);
terom@25: 
terom@25:     // release the engine
terom@25:     switch (conn->evsql->type) {
terom@25:         case EVSQL_EVPQ:
terom@25:             evpq_release(conn->engine.evpq);
terom@25:             break;
terom@25:         
terom@25:         default:
terom@25:             FATAL("evsql->type");
terom@25:     }
terom@25:     
terom@25:     // remove from list
terom@25:     LIST_REMOVE(conn, entry);
terom@25: 
terom@25:     // free
terom@25:     free(conn);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Fail a single query, this will trigger the callback and free it.
terom@25:  */
terom@25: static void _evsql_query_fail (struct evsql* evsql, struct evsql_query *query) {
terom@25:     struct evsql_result_info res; ZINIT(res);
terom@25:     
terom@25:     // set up the result_info
terom@25:     res.evsql = evsql;
terom@25:     res.error = 1;
terom@25:     
terom@25:     // finish off the query
terom@25:     _evsql_query_done(query, &res);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Fail a transaction, this will silently drop any query, trigger the error callback, two-way-deassociate/release the
terom@25:  * conn, and then free the trans.
terom@25:  */ 
terom@25: static void _evsql_trans_fail (struct evsql_trans *trans) {
terom@25:     if (trans->query) {
terom@25:         // free the query silently
terom@25:         _evsql_query_free(trans->query); trans->query = NULL;
terom@25:     }
terom@25: 
terom@25:     // tell the user
terom@25:     // XXX: trans is in a bad state during this call
terom@25:     trans->error_fn(trans, trans->cb_arg);
terom@25: 
terom@25:     // fail the conn
terom@25:     trans->conn->trans = NULL; _evsql_conn_release(trans->conn); trans->conn = NULL;
terom@25: 
terom@25:     // free the trans
terom@25:     _evsql_trans_free(trans);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Fail a connection. If the connection is transactional, this will just call _evsql_trans_fail, but otherwise it will
terom@25:  * fail any ongoing query, and then release the connection.
terom@25:  */
terom@25: static void _evsql_conn_fail (struct evsql_conn *conn) {
terom@25:     if (conn->trans) {
terom@25:         // let transactions handle their connection failures
terom@25:         _evsql_trans_fail(conn->trans);
terom@25: 
terom@25:     } else {
terom@25:         if (conn->query) {
terom@25:             // fail the in-progress query
terom@25:             _evsql_query_fail(conn->evsql, conn->query); conn->query = NULL;
terom@21:         }
terom@21: 
terom@25:         // finish off the whole connection
terom@25:         _evsql_conn_release(conn);
terom@21:     }
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * Processes enqueued non-transactional queries until the queue is empty, or we managed to exec a query.
terom@25:  *
terom@25:  * If execing a query on a connection fails, both the query and the connection are failed (in that order).
terom@25:  *
terom@25:  * Any further queries will then also be failed, because there's no reconnection/retry logic yet.
terom@25:  */
terom@25: static void _evsql_pump (struct evsql *evsql, struct evsql_conn *conn) {
terom@25:     struct evsql_query *query;
terom@25:     int err;
terom@25:     
terom@25:     // look for waiting queries
terom@25:     while ((query = TAILQ_FIRST(&evsql->query_queue)) != NULL) {
terom@25:         // dequeue
terom@25:         TAILQ_REMOVE(&evsql->query_queue, query, entry);
terom@25:         
terom@25:         if (conn) {
terom@25:             // try and execute it
terom@25:             err = _evsql_query_exec(conn, query, query->command);
terom@25:         }
terom@21: 
terom@25:         // free the command buf
terom@25:         free(query->command); query->command = NULL;
terom@21: 
terom@25:         if (err || !conn) {
terom@25:             if (!conn) {
terom@25:                 // warn when dropping queries
terom@25:                 WARNING("failing query becuse there are no conns");
terom@25:             }
terom@25: 
terom@25:             // fail the query
terom@25:             _evsql_query_fail(evsql, query);
terom@25:             
terom@25:             if (conn) {
terom@25:                 // fail the connection
terom@25:                 WARNING("failing the connection because a query-exec failed");
terom@25: 
terom@25:                 _evsql_conn_fail(conn); conn = NULL;
terom@25:             }
terom@25: 
terom@25:         } else {
terom@25:             // we have succesfully enqueued a query, and we can wait for this connection to complete
terom@25:             break;
terom@25: 
terom@25:         }
terom@25: 
terom@25:         // handle the rest of the queue
terom@25:     }
terom@25:     
terom@25:     // ok
terom@25:     return;
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * Callback for a trans's 'BEGIN' query, which means the transaction is now ready for use.
terom@25:  */
terom@25: static void _evsql_trans_ready (const struct evsql_result_info *res, void *arg) {
terom@25:     (void) arg;
terom@21: 
terom@25:     assert(res->trans);
terom@25: 
terom@25:     // check for errors
terom@25:     if (res->error)
terom@25:         ERROR("transaction 'BEGIN' failed: %s", evsql_result_error(res));
terom@25:     
terom@25:     // transaction is now ready for use
terom@25:     res->trans->ready_fn(res->trans, res->trans->cb_arg);
terom@25: 
terom@25: error:
terom@25:     _evsql_trans_fail(res->trans);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * The transaction's connection is ready, send the 'BEGIN' query.
terom@25:  */
terom@25: static void _evsql_trans_conn_ready (struct evsql *evsql, struct evsql_trans *trans) {
terom@25:     char trans_sql[EVSQL_QUERY_BEGIN_BUF];
terom@25:     const char *isolation_level;
terom@25:     int ret;
terom@25:     
terom@25:     // determine the isolation_level to use
terom@25:     switch (trans->type) {
terom@25:         case EVSQL_TRANS_DEFAULT:
terom@25:             isolation_level = NULL; break;
terom@25: 
terom@25:         case EVSQL_TRANS_SERIALIZABLE:
terom@25:             isolation_level = "SERIALIZABLE"; break;
terom@25: 
terom@25:         case EVSQL_TRANS_REPEATABLE_READ:
terom@25:             isolation_level = "REPEATABLE READ"; break;
terom@25: 
terom@25:         case EVSQL_TRANS_READ_COMMITTED:
terom@25:             isolation_level = "READ COMMITTED"; break;
terom@25: 
terom@25:         case EVSQL_TRANS_READ_UNCOMMITTED:
terom@25:             isolation_level = "READ UNCOMMITTED"; break;
terom@25: 
terom@25:         default:
terom@25:             FATAL("trans->type: %d", trans->type);
terom@25:     }
terom@25:     
terom@25:     // build the trans_sql
terom@25:     if (isolation_level)
terom@25:         ret = snprintf(trans_sql, EVSQL_QUERY_BEGIN_BUF, "BEGIN TRANSACTION ISOLATION LEVEL %s", isolation_level);
terom@25:     else
terom@25:         ret = snprintf(trans_sql, EVSQL_QUERY_BEGIN_BUF, "BEGIN TRANSACTION");
terom@25:     
terom@25:     // make sure it wasn't truncated
terom@25:     if (ret >= EVSQL_QUERY_BEGIN_BUF)
terom@25:         ERROR("trans_sql overflow: %d >= %d", ret, EVSQL_QUERY_BEGIN_BUF);
terom@25:     
terom@25:     // execute the query
terom@25:     if (evsql_query(evsql, trans, trans_sql, _evsql_trans_ready, NULL))
terom@25:         ERROR("evsql_query");
terom@25:     
terom@25:     // success
terom@25:     return;
terom@25: 
terom@25: error:
terom@25:     // fail the transaction
terom@25:     _evsql_trans_fail(trans);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * The evpq connection was succesfully established.
terom@25:  */ 
terom@25: static void _evsql_evpq_connected (struct evpq_conn *_conn, void *arg) {
terom@25:     struct evsql_conn *conn = arg;
terom@25: 
terom@25:     if (conn->trans)
terom@25:         // notify the transaction
terom@25:         _evsql_trans_conn_ready(conn->evsql, conn->trans);
terom@25:     
terom@25:     else
terom@25:         // pump any waiting transactionless queries
terom@25:         _evsql_pump(conn->evsql, conn);
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Got one result on this evpq connection.
terom@25:  */
terom@25: static void _evsql_evpq_result (struct evpq_conn *_conn, PGresult *result, void *arg) {
terom@25:     struct evsql_conn *conn = arg;
terom@25:     struct evsql_query *query = conn->query;
terom@25: 
terom@25:     assert(query != NULL);
terom@21: 
terom@21:     // if we get multiple results, only return the first one
terom@21:     if (query->result.evpq) {
terom@21:         WARNING("[evsql] evpq query returned multiple results, discarding previous one");
terom@21:         
terom@21:         PQclear(query->result.evpq); query->result.evpq = NULL;
terom@21:     }
terom@21:     
terom@21:     // remember the result
terom@21:     query->result.evpq = result;
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * No more results for this query.
terom@25:  */
terom@25: static void _evsql_evpq_done (struct evpq_conn *_conn, void *arg) {
terom@25:     struct evsql_conn *conn = arg;
terom@25:     struct evsql_query *query = conn->query;
terom@24:     struct evsql_result_info res; ZINIT(res);
terom@25:     
terom@25:     assert(query != NULL);
terom@21:     
terom@21:     // set up the result_info
terom@25:     res.evsql = conn->evsql;
terom@21:     
terom@21:     if (query->result.evpq == NULL) {
terom@21:         // if a query didn't return any results (bug?), warn and fail the query
terom@21:         WARNING("[evsql] evpq query didn't return any results");
terom@21: 
terom@24:         res.error = 1;
terom@24:     
terom@24:     } else if (strcmp(PQresultErrorMessage(query->result.evpq), "") != 0) {
terom@24:         // the query failed with some error
terom@24:         res.error = 1;
terom@24:         res.result.pq = query->result.evpq;
terom@21: 
terom@21:     } else {
terom@24:         res.error = 0;
terom@24:         res.result.pq = query->result.evpq;
terom@21: 
terom@21:     }
terom@21: 
terom@25:     // de-associate the query from the connection
terom@25:     conn->query = NULL;
terom@25:     
terom@25:     // how we handle query completion depends on if we're a transaction or not
terom@25:     if (conn->trans) {
terom@25:         // we can deassign the trans's query
terom@25:         conn->trans->query = NULL;
terom@21: 
terom@25:         // then hand the query to the user
terom@25:         _evsql_query_done(query, &res);
terom@25:         
terom@25:     } else {
terom@25:         // a transactionless query, so just finish it off and pump any other waiting ones
terom@25:         _evsql_query_done(query, &res);
terom@25: 
terom@25:         // pump the next one
terom@25:         _evsql_pump(conn->evsql, conn);
terom@25:     }
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * The connection failed.
terom@25:  */
terom@25: static void _evsql_evpq_failure (struct evpq_conn *_conn, void *arg) {
terom@25:     struct evsql_conn *conn = arg;
terom@21:     
terom@25:     // just fail the conn
terom@25:     _evsql_conn_fail(conn);
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * Our evpq behaviour
terom@25:  */
terom@21: static struct evpq_callback_info _evsql_evpq_cb_info = {
terom@21:     .fn_connected       = _evsql_evpq_connected,
terom@21:     .fn_result          = _evsql_evpq_result,
terom@21:     .fn_done            = _evsql_evpq_done,
terom@21:     .fn_failure         = _evsql_evpq_failure,
terom@21: };
terom@21: 
terom@25: /*
terom@25:  * Allocate the generic evsql context.
terom@25:  */
terom@25: static struct evsql *_evsql_new_base (struct event_base *ev_base, evsql_error_cb error_fn, void *cb_arg) {
terom@21:     struct evsql *evsql = NULL;
terom@21:     
terom@21:     // allocate it
terom@21:     if ((evsql = calloc(1, sizeof(*evsql))) == NULL)
terom@21:         ERROR("calloc");
terom@21: 
terom@21:     // store
terom@25:     evsql->ev_base = ev_base;
terom@21:     evsql->error_fn = error_fn;
terom@21:     evsql->cb_arg = cb_arg;
terom@21: 
terom@21:     // init
terom@25:     LIST_INIT(&evsql->conn_list);
terom@25:     TAILQ_INIT(&evsql->query_queue);
terom@21: 
terom@21:     // done
terom@21:     return evsql;
terom@21: 
terom@21: error:
terom@21:     return NULL;
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * Start a new connection and add it to the list, it won't be ready until _evsql_evpq_connected is called
terom@25:  */
terom@25: static struct evsql_conn *_evsql_conn_new (struct evsql *evsql) {
terom@25:     struct evsql_conn *conn = NULL;
terom@25:     
terom@25:     // allocate
terom@25:     if ((conn = calloc(1, sizeof(*conn))) == NULL)
terom@25:         ERROR("calloc");
terom@25: 
terom@25:     // init
terom@25:     conn->evsql = evsql;
terom@25:     
terom@25:     // connect the engine
terom@25:     switch (evsql->type) {
terom@25:         case EVSQL_EVPQ:
terom@25:             if ((conn->engine.evpq = evpq_connect(evsql->ev_base, evsql->engine_conf.evpq, _evsql_evpq_cb_info, conn)) == NULL)
terom@25:                 goto error;
terom@25:             
terom@25:             break;
terom@25:             
terom@25:         default:
terom@25:             FATAL("evsql->type");
terom@25:     }
terom@25: 
terom@25:     // add it to the list
terom@25:     LIST_INSERT_HEAD(&evsql->conn_list, conn, entry);
terom@25: 
terom@25:     // success
terom@25:     return conn;
terom@25: 
terom@25: error:
terom@25:     free(conn);
terom@25: 
terom@25:     return NULL;
terom@25: }
terom@25: 
terom@21: struct evsql *evsql_new_pq (struct event_base *ev_base, const char *pq_conninfo, evsql_error_cb error_fn, void *cb_arg) {
terom@21:     struct evsql *evsql = NULL;
terom@21:     
terom@21:     // base init
terom@25:     if ((evsql = _evsql_new_base (ev_base, error_fn, cb_arg)) == NULL)
terom@21:         goto error;
terom@21: 
terom@25:     // store conf
terom@25:     evsql->engine_conf.evpq = pq_conninfo;
terom@25: 
terom@25:     // pre-create one connection
terom@25:     if (_evsql_conn_new(evsql) == NULL)
terom@21:         goto error;
terom@21: 
terom@21:     // done
terom@21:     return evsql;
terom@21: 
terom@21: error:
terom@21:     // XXX: more complicated than this?
terom@21:     free(evsql); 
terom@21: 
terom@21:     return NULL;
terom@21: }
terom@21: 
terom@21: /*
terom@25:  * Checks if the connection is already allocated for some other trans/query.
terom@21:  *
terom@21:  * Returns:
terom@25:  *      0       connection idle, can be allocated
terom@25:  *      >1      connection busy
terom@21:  */
terom@25: static int _evsql_conn_busy (struct evsql_conn *conn) {
terom@25:     // transactions get the connection to themselves
terom@25:     if (conn->trans)
terom@25:         return 1;
terom@25:     
terom@25:     // if it has a query assigned, it's busy
terom@25:     if (conn->query)
terom@25:         return 1;
terom@25: 
terom@25:     // otherwise, it's all idle
terom@25:     return 0;
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Checks if the connection is ready for use (i.e. _evsql_evpq_connected was called).
terom@25:  *
terom@25:  * The connection should not already have a query running.
terom@25:  *
terom@25:  * Returns 
terom@25:  *  <0  the connection is not valid (failed, query in progress)
terom@25:  *  0   the connection is still pending, and will become ready at some point
terom@25:  *  >0  it's ready
terom@25:  */
terom@25: static int _evsql_conn_ready (struct evsql_conn *conn) {
terom@25:     switch (conn->evsql->type) {
terom@21:         case EVSQL_EVPQ: {
terom@25:             enum evpq_state state = evpq_state(conn->engine.evpq);
terom@21:             
terom@21:             switch (state) {
terom@21:                 case EVPQ_CONNECT:
terom@25:                     return 0;
terom@21:                 
terom@21:                 case EVPQ_CONNECTED:
terom@25:                     return 1;
terom@21: 
terom@25:                 case EVPQ_QUERY:
terom@21:                 case EVPQ_INIT:
terom@21:                 case EVPQ_FAILURE:
terom@21:                     return -1;
terom@21:                 
terom@21:                 default:
terom@25:                     FATAL("evpq_state: %d", state);
terom@21:             }
terom@21: 
terom@21:         }
terom@21:         
terom@21:         default:
terom@25:             FATAL("evsql->type: %d", conn->evsql->type);
terom@21:     }
terom@21: }
terom@21: 
terom@25: /*
terom@25:  * Allocate a connection for use and return it via *conn_ptr, or if may_queue is nonzero and the connection pool is
terom@25:  * getting full, return NULL (query should be queued).
terom@25:  *
terom@25:  * Note that the returned connection might not be ready for use yet (if we created a new one, see _evsql_conn_ready).
terom@25:  *
terom@25:  * Returns zero if a connection was found or the request should be queued, or nonzero if something failed and the
terom@25:  * request should be dropped.
terom@25:  */
terom@25: static int _evsql_conn_get (struct evsql *evsql, struct evsql_conn **conn_ptr, int may_queue) {
terom@25:     *conn_ptr = NULL;
terom@25:     
terom@25:     // find a connection that isn't busy and is ready (unless the query queue is empty).
terom@25:     LIST_FOREACH(*conn_ptr, &evsql->conn_list, entry) {
terom@25:         // skip busy conns always
terom@25:         if (_evsql_conn_busy(*conn_ptr))
terom@25:             continue;
terom@25:         
terom@25:         // accept pending conns as long as there are NO enqueued queries (might cause deadlock otherwise)
terom@25:         if (_evsql_conn_ready(*conn_ptr) == 0 && TAILQ_EMPTY(&evsql->query_queue))
terom@25:             break;
terom@25: 
terom@25:         // accept conns that are in a fully ready state
terom@25:         if (_evsql_conn_ready(*conn_ptr) > 0)
terom@25:             break;
terom@25:     }
terom@25:     
terom@25:     // if we found an idle connection, we can just return that right away
terom@25:     if (*conn_ptr)
terom@25:         return 0;
terom@25: 
terom@25:     // return NULL if may_queue and the conn list is not empty
terom@25:     if (may_queue && !LIST_EMPTY(&evsql->conn_list))
terom@25:         return 0;
terom@25:     
terom@25:     // we need to open a new connection
terom@25:     if ((*conn_ptr = _evsql_conn_new(evsql)) == NULL)
terom@25:         goto error;
terom@25: 
terom@25:     // good
terom@25:     return 0;
terom@25: error:
terom@25:     return -1;
terom@25: }
terom@25: 
terom@25: /*
terom@25:  * Validate and allocate the basic stuff for a new query.
terom@25:  */
terom@25: static struct evsql_query *_evsql_query_new (struct evsql *evsql, struct evsql_trans *trans, evsql_query_cb query_fn, void *cb_arg) {
terom@21:     struct evsql_query *query;
terom@23:     
terom@25:     // if it's part of a trans, then make sure the trans is idle
terom@25:     if (trans && trans->query)
terom@25:         ERROR("transaction is busy");
terom@25: 
terom@21:     // allocate it
terom@21:     if ((query = calloc(1, sizeof(*query))) == NULL)
terom@21:         ERROR("calloc");
terom@21: 
terom@21:     // store
terom@21:     query->cb_fn = query_fn;
terom@21:     query->cb_arg = cb_arg;
terom@23: 
terom@23:     // success
terom@23:     return query;
terom@23: 
terom@23: error:
terom@23:     return NULL;
terom@23: }
terom@23: 
terom@25: /*
terom@25:  * Handle a new query.
terom@25:  *
terom@25:  * For transactions this will associate the query and then execute it, otherwise this will either find an idle
terom@25:  * connection and send the query, or enqueue it.
terom@25:  */
terom@25: static int _evsql_query_enqueue (struct evsql *evsql, struct evsql_trans *trans, struct evsql_query *query, const char *command) {
terom@25:     // transaction queries are handled differently
terom@25:     if (trans) {
terom@25:         // it's an in-transaction query
terom@25:         assert(trans->query == NULL);
terom@25:         
terom@25:         // assign the query
terom@25:         trans->query = query;
terom@25: 
terom@25:         // execute directly
terom@25:         if (_evsql_query_exec(trans->conn, query, command))
terom@25:             goto error;
terom@24: 
terom@24:     } else {
terom@25:         struct evsql_conn *conn;
terom@25:         
terom@25:         // find an idle connection
terom@25:         if ((_evsql_conn_get(evsql, &conn, 1)))
terom@25:             ERROR("couldn't allocate a connection for the query");
terom@21: 
terom@25:         // we must enqueue if no idle conn or the conn is not yet ready
terom@25:         if (conn && _evsql_conn_ready(conn) > 0) {
terom@25:             // execute directly
terom@25:             if (_evsql_query_exec(conn, query, command))
terom@25:                 goto error;
terom@21: 
terom@25: 
terom@25:         } else {
terom@25:             // copy the command for later execution
terom@25:             if ((query->command = strdup(command)) == NULL)
terom@25:                 ERROR("strdup");
terom@25:             
terom@25:             // enqueue until some connection pumps the queue
terom@25:             TAILQ_INSERT_TAIL(&evsql->query_queue, query, entry);
terom@25:         }
terom@21:     }
terom@23: 
terom@23:     // ok, good
terom@23:     return 0;
terom@23: 
terom@23: error:
terom@23:     return -1;
terom@23: }
terom@23: 
terom@25: struct evsql_query *evsql_query (struct evsql *evsql, struct evsql_trans *trans, const char *command, evsql_query_cb query_fn, void *cb_arg) {
terom@23:     struct evsql_query *query = NULL;
terom@21:     
terom@23:     // alloc new query
terom@25:     if ((query = _evsql_query_new(evsql, trans, query_fn, cb_arg)) == NULL)
terom@23:         goto error;
terom@23:     
terom@23:     // just execute the command string directly
terom@25:     if (_evsql_query_enqueue(evsql, trans, query, command))
terom@23:         goto error;
terom@23: 
terom@23:     // ok
terom@21:     return query;
terom@21: 
terom@21: error:
terom@23:     _evsql_query_free(query);
terom@21: 
terom@21:     return NULL;
terom@21: }
terom@21: 
terom@25: struct evsql_query *evsql_query_params (struct evsql *evsql, struct evsql_trans *trans, const char *command, const struct evsql_query_params *params, evsql_query_cb query_fn, void *cb_arg) {
terom@23:     struct evsql_query *query = NULL;
terom@24:     const struct evsql_query_param *param;
terom@23:     int idx;
terom@23:     
terom@23:     // alloc new query
terom@25:     if ((query = _evsql_query_new(evsql, trans, query_fn, cb_arg)) == NULL)
terom@23:         goto error;
terom@23: 
terom@23:     // count the params
terom@24:     for (param = params->list; param->type; param++) 
terom@23:         query->params.count++;
terom@23: 
terom@23:     // allocate the vertical storage for the parameters
terom@23:     if (0
terom@23:         
terom@23: //            !(query->params.types    = calloc(query->params.count, sizeof(Oid)))
terom@23:         ||  !(query->params.values   = calloc(query->params.count, sizeof(char *)))
terom@23:         ||  !(query->params.lengths  = calloc(query->params.count, sizeof(int)))
terom@23:         ||  !(query->params.formats  = calloc(query->params.count, sizeof(int)))
terom@23:     )
terom@23:         ERROR("calloc");
terom@23: 
terom@23:     // transform
terom@24:     for (param = params->list, idx = 0; param->type; param++, idx++) {
terom@23:         // `types` stays NULL
terom@23:         // query->params.types[idx] = 0;
terom@23:         
terom@23:         // values
terom@24:         query->params.values[idx] = param->data_raw;
terom@23: 
terom@24:         // lengths
terom@24:         query->params.lengths[idx] = param->length;
terom@23: 
terom@23:         // formats, binary if length is nonzero
terom@24:         query->params.formats[idx] = param->length ? 1 : 0;
terom@23:     }
terom@23: 
terom@23:     // result format
terom@24:     switch (params->result_fmt) {
terom@24:         case EVSQL_FMT_TEXT:
terom@24:             query->params.result_format = 0; break;
terom@24: 
terom@24:         case EVSQL_FMT_BINARY:
terom@24:             query->params.result_format = 1; break;
terom@24: 
terom@24:         default:
terom@24:             FATAL("params.result_fmt: %d", params->result_fmt);
terom@24:     }
terom@23: 
terom@23:     // execute it
terom@25:     if (_evsql_query_enqueue(evsql, trans, query, command))
terom@23:         goto error;
terom@23: 
terom@23:     // ok
terom@23:     return query;
terom@23: 
terom@23: error:
terom@23:     _evsql_query_free(query);
terom@23:     
terom@23:     return NULL;
terom@23: }
terom@23: