From 7a18bcc516391bb78976dd11d97f9c2cdc4d6168 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 30 May 2025 14:18:47 -0400 Subject: [PATCH v8 2/4] Reap the benefits of not having to avoid leaking PGresults. Remove a bunch of PG_TRY constructs, de-volatilize related variables, remove some PQclear calls in error paths. Aside from making the code simpler and shorter, this should provide some marginal performance gains. For ease of review, I did not re-indent code within the removed PG_TRY constructs. That'll be done in a separate patch. Author: Tom Lane Reviewed-by: Matheus Alcantara Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us --- contrib/dblink/dblink.c | 96 +++-------- contrib/postgres_fdw/connection.c | 52 ++---- contrib/postgres_fdw/postgres_fdw.c | 163 ++++-------------- contrib/postgres_fdw/postgres_fdw.h | 2 +- .../libpqwalreceiver/libpqwalreceiver.c | 31 +--- src/include/libpq/libpq-be-fe-helpers.h | 13 +- 6 files changed, 83 insertions(+), 274 deletions(-) diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c index 8a0b112a7ff..c41df97b314 100644 --- a/contrib/dblink/dblink.c +++ b/contrib/dblink/dblink.c @@ -101,8 +101,8 @@ static void materializeQueryResult(FunctionCallInfo fcinfo, const char *conname, const char *sql, bool fail); -static PGresult *storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql); -static void storeRow(volatile storeInfo *sinfo, PGresult *res, bool first); +static PGresult *storeQueryResult(storeInfo *sinfo, PGconn *conn, const char *sql); +static void storeRow(storeInfo *sinfo, PGresult *res, bool first); static remoteConn *getConnectionByName(const char *name); static HTAB *createConnHash(void); static remoteConn *createNewConnection(const char *name); @@ -169,14 +169,6 @@ typedef struct remoteConnHashEnt /* initial number of connection hashes */ #define NUMCONN 16 -static char * -xpstrdup(const char *in) -{ - if (in == NULL) - return NULL; - return pstrdup(in); -} - pg_noreturn static void dblink_res_internalerror(PGconn *conn, PGresult *res, const char *p2) { @@ -863,17 +855,14 @@ static void materializeResult(FunctionCallInfo fcinfo, PGconn *conn, PGresult *res) { ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; + TupleDesc tupdesc; + bool is_sql_cmd; + int ntuples; + int nfields; /* prepTuplestoreResult must have been called previously */ Assert(rsinfo->returnMode == SFRM_Materialize); - PG_TRY(); - { - TupleDesc tupdesc; - bool is_sql_cmd; - int ntuples; - int nfields; - if (PQresultStatus(res) == PGRES_COMMAND_OK) { is_sql_cmd = true; @@ -981,13 +970,8 @@ materializeResult(FunctionCallInfo fcinfo, PGconn *conn, PGresult *res) /* clean up GUC settings, if we changed any */ restoreLocalGucs(nestlevel); } - } - PG_FINALLY(); - { - /* be sure to release the libpq result */ + PQclear(res); - } - PG_END_TRY(); } /* @@ -1006,16 +990,17 @@ materializeQueryResult(FunctionCallInfo fcinfo, bool fail) { ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; - PGresult *volatile res = NULL; - volatile storeInfo sinfo = {0}; /* prepTuplestoreResult must have been called previously */ Assert(rsinfo->returnMode == SFRM_Materialize); - sinfo.fcinfo = fcinfo; - + /* Use a PG_TRY block to ensure we pump libpq dry of results */ PG_TRY(); { + storeInfo sinfo = {0}; + PGresult *res; + + sinfo.fcinfo = fcinfo; /* Create short-lived memory context for data conversions */ sinfo.tmpcontext = AllocSetContextCreate(CurrentMemoryContext, "dblink temporary context", @@ -1028,14 +1013,7 @@ materializeQueryResult(FunctionCallInfo fcinfo, (PQresultStatus(res) != PGRES_COMMAND_OK && PQresultStatus(res) != PGRES_TUPLES_OK)) { - /* - * dblink_res_error will clear the passed PGresult, so we need - * this ugly dance to avoid doing so twice during error exit - */ - PGresult *res1 = res; - - res = NULL; - dblink_res_error(conn, conname, res1, fail, + dblink_res_error(conn, conname, res, fail, "while executing query"); /* if fail isn't set, we'll return an empty query result */ } @@ -1074,7 +1052,6 @@ materializeQueryResult(FunctionCallInfo fcinfo, tuplestore_puttuple(tupstore, tuple); PQclear(res); - res = NULL; } else { @@ -1083,26 +1060,20 @@ materializeQueryResult(FunctionCallInfo fcinfo, Assert(rsinfo->setResult != NULL); PQclear(res); - res = NULL; } /* clean up data conversion short-lived memory context */ if (sinfo.tmpcontext != NULL) MemoryContextDelete(sinfo.tmpcontext); - sinfo.tmpcontext = NULL; PQclear(sinfo.last_res); - sinfo.last_res = NULL; PQclear(sinfo.cur_res); - sinfo.cur_res = NULL; } PG_CATCH(); { - /* be sure to release any libpq result we collected */ - PQclear(res); - PQclear(sinfo.last_res); - PQclear(sinfo.cur_res); - /* and clear out any pending data in libpq */ + PGresult *res; + + /* be sure to clear out any pending data in libpq */ while ((res = libpqsrv_get_result(conn, dblink_we_get_result)) != NULL) PQclear(res); @@ -1115,7 +1086,7 @@ materializeQueryResult(FunctionCallInfo fcinfo, * Execute query, and send any result rows to sinfo->tuplestore. */ static PGresult * -storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql) +storeQueryResult(storeInfo *sinfo, PGconn *conn, const char *sql) { bool first = true; int nestlevel = -1; @@ -1183,7 +1154,7 @@ storeQueryResult(volatile storeInfo *sinfo, PGconn *conn, const char *sql) * (in this case the PGresult might contain either zero or one row). */ static void -storeRow(volatile storeInfo *sinfo, PGresult *res, bool first) +storeRow(storeInfo *sinfo, PGresult *res, bool first) { int nfields = PQnfields(res); HeapTuple tuple; @@ -2788,10 +2759,13 @@ dblink_connstr_check(const char *connstr) /* * Report an error received from the remote server * - * res: the received error result (will be freed) + * res: the received error result * fail: true for ERROR ereport, false for NOTICE * fmt and following args: sprintf-style format and values for errcontext; * the resulting string should be worded like "while " + * + * If "res" is not NULL, it'll be PQclear'ed here (unless we throw error, + * in which case memory context cleanup will clear it eventually). */ static void dblink_res_error(PGconn *conn, const char *conname, PGresult *res, @@ -2799,15 +2773,11 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res, { int level; char *pg_diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE); - char *pg_diag_message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY); - char *pg_diag_message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL); - char *pg_diag_message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT); - char *pg_diag_context = PQresultErrorField(res, PG_DIAG_CONTEXT); + char *message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY); + char *message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL); + char *message_hint = PQresultErrorField(res, PG_DIAG_MESSAGE_HINT); + char *message_context = PQresultErrorField(res, PG_DIAG_CONTEXT); int sqlstate; - char *message_primary; - char *message_detail; - char *message_hint; - char *message_context; va_list ap; char dblink_context_msg[512]; @@ -2825,11 +2795,6 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res, else sqlstate = ERRCODE_CONNECTION_FAILURE; - message_primary = xpstrdup(pg_diag_message_primary); - message_detail = xpstrdup(pg_diag_message_detail); - message_hint = xpstrdup(pg_diag_message_hint); - message_context = xpstrdup(pg_diag_context); - /* * If we don't get a message from the PGresult, try the PGconn. This is * needed because for connection-level failures, PQgetResult may just @@ -2838,14 +2803,6 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res, if (message_primary == NULL) message_primary = pchomp(PQerrorMessage(conn)); - /* - * Now that we've copied all the data we need out of the PGresult, it's - * safe to free it. We must do this to avoid PGresult leakage. We're - * leaking all the strings too, but those are in palloc'd memory that will - * get cleaned up eventually. - */ - PQclear(res); - /* * Format the basic errcontext string. Below, we'll add on something * about the connection name. That's a violation of the translatability @@ -2870,6 +2827,7 @@ dblink_res_error(PGconn *conn, const char *conname, PGresult *res, dblink_context_msg, conname)) : (errcontext("%s on unnamed dblink connection", dblink_context_msg)))); + PQclear(res); } /* diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 304f3c20f83..2082c0b2ff8 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -812,7 +812,7 @@ static void do_sql_command_begin(PGconn *conn, const char *sql) { if (!PQsendQuery(conn, sql)) - pgfdw_report_error(ERROR, NULL, conn, false, sql); + pgfdw_report_error(ERROR, NULL, conn, sql); } static void @@ -827,10 +827,10 @@ do_sql_command_end(PGconn *conn, const char *sql, bool consume_input) * would be large compared to the overhead of PQconsumeInput.) */ if (consume_input && !PQconsumeInput(conn)) - pgfdw_report_error(ERROR, NULL, conn, false, sql); + pgfdw_report_error(ERROR, NULL, conn, sql); res = pgfdw_get_result(conn); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, conn, true, sql); + pgfdw_report_error(ERROR, res, conn, sql); PQclear(res); } @@ -964,22 +964,21 @@ pgfdw_get_result(PGconn *conn) * Report an error we got from the remote server. * * elevel: error level to use (typically ERROR, but might be less) - * res: PGresult containing the error + * res: PGresult containing the error (might be NULL) * conn: connection we did the query on - * clear: if true, PQclear the result (otherwise caller will handle it) * sql: NULL, or text of remote command we tried to execute * + * If "res" is not NULL, it'll be PQclear'ed here (unless we throw error, + * in which case memory context cleanup will clear it eventually). + * * Note: callers that choose not to throw ERROR for a remote error are * responsible for making sure that the associated ConnCacheEntry gets * marked with have_error = true. */ void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, - bool clear, const char *sql) + const char *sql) { - /* If requested, PGresult must be released before leaving this function. */ - PG_TRY(); - { char *diag_sqlstate = PQresultErrorField(res, PG_DIAG_SQLSTATE); char *message_primary = PQresultErrorField(res, PG_DIAG_MESSAGE_PRIMARY); char *message_detail = PQresultErrorField(res, PG_DIAG_MESSAGE_DETAIL); @@ -1013,13 +1012,7 @@ pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, message_hint ? errhint("%s", message_hint) : 0, message_context ? errcontext("%s", message_context) : 0, sql ? errcontext("remote SQL command: %s", sql) : 0)); - } - PG_FINALLY(); - { - if (clear) PQclear(res); - } - PG_END_TRY(); } /* @@ -1542,7 +1535,7 @@ pgfdw_exec_cleanup_query_begin(PGconn *conn, const char *query) */ if (!PQsendQuery(conn, query)) { - pgfdw_report_error(WARNING, NULL, conn, false, query); + pgfdw_report_error(WARNING, NULL, conn, query); return false; } @@ -1567,7 +1560,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query, */ if (consume_input && !PQconsumeInput(conn)) { - pgfdw_report_error(WARNING, NULL, conn, false, query); + pgfdw_report_error(WARNING, NULL, conn, query); return false; } @@ -1579,7 +1572,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query, (errmsg("could not get query result due to timeout"), errcontext("remote SQL command: %s", query))); else - pgfdw_report_error(WARNING, NULL, conn, false, query); + pgfdw_report_error(WARNING, NULL, conn, query); return false; } @@ -1587,7 +1580,7 @@ pgfdw_exec_cleanup_query_end(PGconn *conn, const char *query, /* Issue a warning if not successful. */ if (PQresultStatus(result) != PGRES_COMMAND_OK) { - pgfdw_report_error(WARNING, result, conn, true, query); + pgfdw_report_error(WARNING, result, conn, query); return ignore_errors; } PQclear(result); @@ -1615,17 +1608,12 @@ pgfdw_get_cleanup_result(PGconn *conn, TimestampTz endtime, PGresult **result, bool *timed_out) { - volatile bool failed = false; - PGresult *volatile last_res = NULL; + bool failed = false; + PGresult *last_res = NULL; + int canceldelta = RETRY_CANCEL_TIMEOUT * 2; *result = NULL; *timed_out = false; - - /* In what follows, do not leak any PGresults on an error. */ - PG_TRY(); - { - int canceldelta = RETRY_CANCEL_TIMEOUT * 2; - for (;;) { PGresult *res; @@ -1703,15 +1691,7 @@ pgfdw_get_cleanup_result(PGconn *conn, TimestampTz endtime, PQclear(last_res); last_res = res; } -exit: ; - } - PG_CATCH(); - { - PQclear(last_res); - PG_RE_THROW(); - } - PG_END_TRY(); - +exit: if (failed) PQclear(last_res); else diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c index 14214b7212e..1be8261061a 100644 --- a/contrib/postgres_fdw/postgres_fdw.c +++ b/contrib/postgres_fdw/postgres_fdw.c @@ -1702,13 +1702,9 @@ postgresReScanForeignScan(ForeignScanState *node) return; } - /* - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. - */ res = pgfdw_exec_query(fsstate->conn, sql, fsstate->conn_state); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fsstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fsstate->conn, sql); PQclear(res); /* Now force a fresh FETCH. */ @@ -3601,11 +3597,7 @@ get_remote_estimate(const char *sql, PGconn *conn, double *rows, int *width, Cost *startup_cost, Cost *total_cost) { - PGresult *volatile res = NULL; - - /* PGresult must be released before leaving this function. */ - PG_TRY(); - { + PGresult *res; char *line; char *p; int n; @@ -3615,7 +3607,7 @@ get_remote_estimate(const char *sql, PGconn *conn, */ res = pgfdw_exec_query(conn, sql, NULL); if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, sql); + pgfdw_report_error(ERROR, res, conn, sql); /* * Extract cost numbers for topmost plan node. Note we search for a @@ -3630,12 +3622,7 @@ get_remote_estimate(const char *sql, PGconn *conn, startup_cost, total_cost, rows, width); if (n != 4) elog(ERROR, "could not interpret EXPLAIN output: \"%s\"", line); - } - PG_FINALLY(); - { PQclear(res); - } - PG_END_TRY(); } /* @@ -3775,17 +3762,14 @@ create_cursor(ForeignScanState *node) */ if (!PQsendQueryParams(conn, buf.data, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, conn, false, buf.data); + pgfdw_report_error(ERROR, NULL, conn, buf.data); /* * Get the result, and check for success. - * - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. */ res = pgfdw_get_result(conn); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, conn, true, fsstate->query); + pgfdw_report_error(ERROR, res, conn, fsstate->query); PQclear(res); /* Mark the cursor as created, and show no tuples have been retrieved */ @@ -3807,7 +3791,10 @@ static void fetch_more_data(ForeignScanState *node) { PgFdwScanState *fsstate = (PgFdwScanState *) node->fdw_state; - PGresult *volatile res = NULL; + PGconn *conn = fsstate->conn; + PGresult *res; + int numrows; + int i; MemoryContext oldcontext; /* @@ -3818,13 +3805,6 @@ fetch_more_data(ForeignScanState *node) MemoryContextReset(fsstate->batch_cxt); oldcontext = MemoryContextSwitchTo(fsstate->batch_cxt); - /* PGresult must be released before leaving this function. */ - PG_TRY(); - { - PGconn *conn = fsstate->conn; - int numrows; - int i; - if (fsstate->async_capable) { Assert(fsstate->conn_state->pendingAreq); @@ -3836,7 +3816,7 @@ fetch_more_data(ForeignScanState *node) res = pgfdw_get_result(conn); /* On error, report the original query, not the FETCH. */ if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, fsstate->query); + pgfdw_report_error(ERROR, res, conn, fsstate->query); /* Reset per-connection state */ fsstate->conn_state->pendingAreq = NULL; @@ -3852,7 +3832,7 @@ fetch_more_data(ForeignScanState *node) res = pgfdw_exec_query(conn, sql, fsstate->conn_state); /* On error, report the original query, not the FETCH. */ if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, fsstate->query); + pgfdw_report_error(ERROR, res, conn, fsstate->query); } /* Convert the data into HeapTuples */ @@ -3880,12 +3860,8 @@ fetch_more_data(ForeignScanState *node) /* Must be EOF if we didn't get as many tuples as we asked for. */ fsstate->eof_reached = (numrows < fsstate->fetch_size); - } - PG_FINALLY(); - { + PQclear(res); - } - PG_END_TRY(); MemoryContextSwitchTo(oldcontext); } @@ -3959,14 +3935,9 @@ close_cursor(PGconn *conn, unsigned int cursor_number, PGresult *res; snprintf(sql, sizeof(sql), "CLOSE c%u", cursor_number); - - /* - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. - */ res = pgfdw_exec_query(conn, sql, conn_state); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, conn, true, sql); + pgfdw_report_error(ERROR, res, conn, sql); PQclear(res); } @@ -4174,18 +4145,15 @@ execute_foreign_modify(EState *estate, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->conn, fmstate->query); /* * Get the result, and check for success. - * - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. */ res = pgfdw_get_result(fmstate->conn); if (PQresultStatus(res) != (fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->conn, fmstate->query); /* Check number of rows affected, and fetch RETURNING tuple if any */ if (fmstate->has_returning) @@ -4244,17 +4212,14 @@ prepare_foreign_modify(PgFdwModifyState *fmstate) fmstate->query, 0, NULL)) - pgfdw_report_error(ERROR, NULL, fmstate->conn, false, fmstate->query); + pgfdw_report_error(ERROR, NULL, fmstate->conn, fmstate->query); /* * Get the result, and check for success. - * - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. */ res = pgfdw_get_result(fmstate->conn); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query); + pgfdw_report_error(ERROR, res, fmstate->conn, fmstate->query); PQclear(res); /* This action shows that the prepare has been done. */ @@ -4345,16 +4310,11 @@ convert_prep_stmt_params(PgFdwModifyState *fmstate, /* * store_returning_result * Store the result of a RETURNING clause - * - * On error, be sure to release the PGresult on the way out. Callers do not - * have PG_TRY blocks to ensure this happens. */ static void store_returning_result(PgFdwModifyState *fmstate, TupleTableSlot *slot, PGresult *res) { - PG_TRY(); - { HeapTuple newtup; newtup = make_tuple_from_result_row(res, 0, @@ -4369,13 +4329,6 @@ store_returning_result(PgFdwModifyState *fmstate, * heaptuples directly, so allow for conversion. */ ExecForceStoreHeapTuple(newtup, slot, true); - } - PG_CATCH(); - { - PQclear(res); - PG_RE_THROW(); - } - PG_END_TRY(); } /* @@ -4411,14 +4364,9 @@ deallocate_query(PgFdwModifyState *fmstate) return; snprintf(sql, sizeof(sql), "DEALLOCATE %s", fmstate->p_name); - - /* - * We don't use a PG_TRY block here, so be careful not to throw error - * without releasing the PGresult. - */ res = pgfdw_exec_query(fmstate->conn, sql, fmstate->conn_state); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, fmstate->conn, true, sql); + pgfdw_report_error(ERROR, res, fmstate->conn, sql); PQclear(res); pfree(fmstate->p_name); fmstate->p_name = NULL; @@ -4586,7 +4534,7 @@ execute_dml_stmt(ForeignScanState *node) */ if (!PQsendQueryParams(dmstate->conn, dmstate->query, numParams, NULL, values, NULL, NULL, 0)) - pgfdw_report_error(ERROR, NULL, dmstate->conn, false, dmstate->query); + pgfdw_report_error(ERROR, NULL, dmstate->conn, dmstate->query); /* * Get the result, and check for success. @@ -4594,7 +4542,7 @@ execute_dml_stmt(ForeignScanState *node) dmstate->result = pgfdw_get_result(dmstate->conn); if (PQresultStatus(dmstate->result) != (dmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK)) - pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, true, + pgfdw_report_error(ERROR, dmstate->result, dmstate->conn, dmstate->query); /* @@ -4940,7 +4888,7 @@ postgresAnalyzeForeignTable(Relation relation, UserMapping *user; PGconn *conn; StringInfoData sql; - PGresult *volatile res = NULL; + PGresult *res; /* Return the row-analysis function pointer */ *func = postgresAcquireSampleRowsFunc; @@ -4966,22 +4914,14 @@ postgresAnalyzeForeignTable(Relation relation, initStringInfo(&sql); deparseAnalyzeSizeSql(&sql, relation); - /* In what follows, do not risk leaking any PGresults. */ - PG_TRY(); - { res = pgfdw_exec_query(conn, sql.data, NULL); if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, sql.data); + pgfdw_report_error(ERROR, res, conn, sql.data); if (PQntuples(res) != 1 || PQnfields(res) != 1) elog(ERROR, "unexpected result from deparseAnalyzeSizeSql query"); *totalpages = strtoul(PQgetvalue(res, 0, 0), NULL, 10); - } - PG_FINALLY(); - { PQclear(res); - } - PG_END_TRY(); ReleaseConnection(conn); @@ -5002,9 +4942,9 @@ postgresGetAnalyzeInfoForForeignTable(Relation relation, bool *can_tablesample) UserMapping *user; PGconn *conn; StringInfoData sql; - PGresult *volatile res = NULL; - volatile double reltuples = -1; - volatile char relkind = 0; + PGresult *res; + double reltuples; + char relkind; /* assume the remote relation does not support TABLESAMPLE */ *can_tablesample = false; @@ -5023,24 +4963,15 @@ postgresGetAnalyzeInfoForForeignTable(Relation relation, bool *can_tablesample) initStringInfo(&sql); deparseAnalyzeInfoSql(&sql, relation); - /* In what follows, do not risk leaking any PGresults. */ - PG_TRY(); - { res = pgfdw_exec_query(conn, sql.data, NULL); if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, sql.data); + pgfdw_report_error(ERROR, res, conn, sql.data); if (PQntuples(res) != 1 || PQnfields(res) != 2) elog(ERROR, "unexpected result from deparseAnalyzeInfoSql query"); reltuples = strtod(PQgetvalue(res, 0, 0), NULL); relkind = *(PQgetvalue(res, 0, 1)); - } - PG_FINALLY(); - { - if (res) PQclear(res); - } - PG_END_TRY(); ReleaseConnection(conn); @@ -5083,7 +5014,9 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, double reltuples; unsigned int cursor_number; StringInfoData sql; - PGresult *volatile res = NULL; + PGresult *res; + char fetch_sql[64]; + int fetch_size; ListCell *lc; /* Initialize workspace state */ @@ -5260,17 +5193,10 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, deparseAnalyzeSql(&sql, relation, method, sample_frac, &astate.retrieved_attrs); - /* In what follows, do not risk leaking any PGresults. */ - PG_TRY(); - { - char fetch_sql[64]; - int fetch_size; - res = pgfdw_exec_query(conn, sql.data, NULL); if (PQresultStatus(res) != PGRES_COMMAND_OK) - pgfdw_report_error(ERROR, res, conn, false, sql.data); + pgfdw_report_error(ERROR, res, conn, sql.data); PQclear(res); - res = NULL; /* * Determine the fetch size. The default is arbitrary, but shouldn't @@ -5321,7 +5247,7 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, res = pgfdw_exec_query(conn, fetch_sql, NULL); /* On error, report the original query, not the FETCH. */ if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, sql.data); + pgfdw_report_error(ERROR, res, conn, sql.data); /* Process whatever we got. */ numrows = PQntuples(res); @@ -5329,7 +5255,6 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, analyze_row_processor(res, i, &astate); PQclear(res); - res = NULL; /* Must be EOF if we didn't get all the rows requested. */ if (numrows < fetch_size) @@ -5338,13 +5263,6 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel, /* Close the cursor, just to be tidy. */ close_cursor(conn, cursor_number, NULL); - } - PG_CATCH(); - { - PQclear(res); - PG_RE_THROW(); - } - PG_END_TRY(); ReleaseConnection(conn); @@ -5456,7 +5374,7 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) UserMapping *mapping; PGconn *conn; StringInfoData buf; - PGresult *volatile res = NULL; + PGresult *res; int numrows, i; ListCell *lc; @@ -5495,16 +5413,13 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) /* Create workspace for strings */ initStringInfo(&buf); - /* In what follows, do not risk leaking any PGresults. */ - PG_TRY(); - { /* Check that the schema really exists */ appendStringInfoString(&buf, "SELECT 1 FROM pg_catalog.pg_namespace WHERE nspname = "); deparseStringLiteral(&buf, stmt->remote_schema); res = pgfdw_exec_query(conn, buf.data, NULL); if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, buf.data); + pgfdw_report_error(ERROR, res, conn, buf.data); if (PQntuples(res) != 1) ereport(ERROR, @@ -5513,7 +5428,6 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) stmt->remote_schema, server->servername))); PQclear(res); - res = NULL; resetStringInfo(&buf); /* @@ -5621,7 +5535,7 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) /* Fetch the data */ res = pgfdw_exec_query(conn, buf.data, NULL); if (PQresultStatus(res) != PGRES_TUPLES_OK) - pgfdw_report_error(ERROR, res, conn, false, buf.data); + pgfdw_report_error(ERROR, res, conn, buf.data); /* Process results */ numrows = PQntuples(res); @@ -5726,12 +5640,7 @@ postgresImportForeignSchema(ImportForeignSchemaStmt *stmt, Oid serverOid) commands = lappend(commands, pstrdup(buf.data)); } - } - PG_FINALLY(); - { PQclear(res); - } - PG_END_TRY(); ReleaseConnection(conn); @@ -7399,7 +7308,7 @@ postgresForeignAsyncNotify(AsyncRequest *areq) /* On error, report the original query, not the FETCH. */ if (!PQconsumeInput(fsstate->conn)) - pgfdw_report_error(ERROR, NULL, fsstate->conn, false, fsstate->query); + pgfdw_report_error(ERROR, NULL, fsstate->conn, fsstate->query); fetch_more_data(node); @@ -7498,7 +7407,7 @@ fetch_more_data_begin(AsyncRequest *areq) fsstate->fetch_size, fsstate->cursor_number); if (!PQsendQuery(fsstate->conn, sql)) - pgfdw_report_error(ERROR, NULL, fsstate->conn, false, fsstate->query); + pgfdw_report_error(ERROR, NULL, fsstate->conn, fsstate->query); /* Remember that the request is in process */ fsstate->conn_state->pendingAreq = areq; diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index 9cb4ee84139..38e1a885941 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -167,7 +167,7 @@ extern PGresult *pgfdw_get_result(PGconn *conn); extern PGresult *pgfdw_exec_query(PGconn *conn, const char *query, PgFdwConnState *state); extern void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, - bool clear, const char *sql); + const char *sql); /* in option.c */ extern int ExtractConnectionOptions(List *defelems, diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c index 7b4ddf7a8f5..d615f340ac7 100644 --- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c +++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c @@ -418,31 +418,22 @@ libpqrcv_identify_system(WalReceiverConn *conn, TimeLineID *primary_tli) "IDENTIFY_SYSTEM", WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE); if (PQresultStatus(res) != PGRES_TUPLES_OK) - { - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("could not receive database system identifier and timeline ID from " "the primary server: %s", pchomp(PQerrorMessage(conn->streamConn))))); - } /* * IDENTIFY_SYSTEM returns 3 columns in 9.3 and earlier, and 4 columns in * 9.4 and onwards. */ if (PQnfields(res) < 3 || PQntuples(res) != 1) - { - int ntuples = PQntuples(res); - int nfields = PQnfields(res); - - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid response from primary server"), errdetail("Could not identify system: got %d rows and %d fields, expected %d rows and %d or more fields.", - ntuples, nfields, 1, 3))); - } + PQntuples(res), PQnfields(res), 1, 3))); primary_sysid = pstrdup(PQgetvalue(res, 0, 0)); *primary_tli = pg_strtoint32(PQgetvalue(res, 0, 1)); PQclear(res); @@ -604,13 +595,10 @@ libpqrcv_startstreaming(WalReceiverConn *conn, return false; } else if (PQresultStatus(res) != PGRES_COPY_BOTH) - { - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("could not start WAL streaming: %s", pchomp(PQerrorMessage(conn->streamConn))))); - } PQclear(res); return true; } @@ -718,26 +706,17 @@ libpqrcv_readtimelinehistoryfile(WalReceiverConn *conn, cmd, WAIT_EVENT_LIBPQWALRECEIVER_RECEIVE); if (PQresultStatus(res) != PGRES_TUPLES_OK) - { - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("could not receive timeline history file from " "the primary server: %s", pchomp(PQerrorMessage(conn->streamConn))))); - } if (PQnfields(res) != 2 || PQntuples(res) != 1) - { - int ntuples = PQntuples(res); - int nfields = PQnfields(res); - - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("invalid response from primary server"), errdetail("Expected 1 tuple with 2 fields, got %d tuples with %d fields.", - ntuples, nfields))); - } + PQntuples(res), PQnfields(res)))); *filename = pstrdup(PQgetvalue(res, 0, 0)); *len = PQgetlength(res, 0, 1); @@ -841,13 +820,10 @@ libpqrcv_receive(WalReceiverConn *conn, char **buffer, return -1; } else - { - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("could not receive data from WAL stream: %s", pchomp(PQerrorMessage(conn->streamConn))))); - } } if (rawlen < -1) ereport(ERROR, @@ -971,13 +947,10 @@ libpqrcv_create_slot(WalReceiverConn *conn, const char *slotname, pfree(cmd.data); if (PQresultStatus(res) != PGRES_TUPLES_OK) - { - PQclear(res); ereport(ERROR, (errcode(ERRCODE_PROTOCOL_VIOLATION), errmsg("could not create replication slot \"%s\": %s", slotname, pchomp(PQerrorMessage(conn->streamConn))))); - } if (lsn) *lsn = DatumGetLSN(DirectFunctionCall1Coll(pg_lsn_in, InvalidOid, diff --git a/src/include/libpq/libpq-be-fe-helpers.h b/src/include/libpq/libpq-be-fe-helpers.h index 9a0373212da..e9fc59716ad 100644 --- a/src/include/libpq/libpq-be-fe-helpers.h +++ b/src/include/libpq/libpq-be-fe-helpers.h @@ -279,11 +279,8 @@ libpqsrv_exec_params(PGconn *conn, static inline PGresult * libpqsrv_get_result_last(PGconn *conn, uint32 wait_event_info) { - PGresult *volatile lastResult = NULL; + PGresult *lastResult = NULL; - /* In what follows, do not leak any PGresults on an error. */ - PG_TRY(); - { for (;;) { /* Wait for, and collect, the next PGresult. */ @@ -306,14 +303,6 @@ libpqsrv_get_result_last(PGconn *conn, uint32 wait_event_info) PQstatus(conn) == CONNECTION_BAD) break; } - } - PG_CATCH(); - { - PQclear(lastResult); - PG_RE_THROW(); - } - PG_END_TRY(); - return lastResult; } -- 2.43.5