From 36c4d30c8f2474cb9bc5f4eb0f2bec4c5a314003 Mon Sep 17 00:00:00 2001 From: Fujii Masao Date: Tue, 30 Sep 2025 23:52:28 +0900 Subject: [PATCH] pgbench: Fix error reporting in readCommandResponse(). pgbench uses readCommandResponse() to process server responses. When readCommandResponse() encounters an error during a call to PQgetResult() to fetch the current result, it attempts to report it with an additional error message from PQerrorMessage(). However, previously, this extra error message could be lost or become incorrect. The cause was that after fetching the current result (and detecting an error), readCommandResponse() called PQgetResult() again to peek at the next result. This second call could overwrite the libpq connection's error message before the original error was reported, causing the error message retrieved from PQerrorMessage() to be lost or overwritten. This commit fixes the issue by updating readCommandResponse() to use PQresultErrorMessage() instead of PQerrorMessage() to retrieve the error message generated when the PQgetResult() for the current result causes an error, ensuring the correct message is reported. Backpatch to all supported versions. Author: Yugo Nagata Reviewed-by: Chao Li Reviewed-by: Fujii Masao Discussion: https://postgr.es/m/20250925110940.ebacc31725758ec47d5432c6@sraoss.co.jp Backpatch-through: 13 --- src/bin/pgbench/pgbench.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c index 8594d424d60..a48126f8fa3 100644 --- a/src/bin/pgbench/pgbench.c +++ b/src/bin/pgbench/pgbench.c @@ -3320,7 +3320,7 @@ readCommandResponse(CState *st, MetaCommand meta, char *varprefix) pg_log_debug("client %d pipeline ending", st->id); if (PQexitPipelineMode(st->con) != 1) pg_log_error("client %d failed to exit pipeline mode: %s", st->id, - PQerrorMessage(st->con)); + PQresultErrorMessage(res)); break; case PGRES_NONFATAL_ERROR: @@ -3330,7 +3330,7 @@ readCommandResponse(CState *st, MetaCommand meta, char *varprefix) if (canRetryError(st->estatus)) { if (verbose_errors) - commandError(st, PQerrorMessage(st->con)); + commandError(st, PQresultErrorMessage(res)); goto error; } /* fall through */ @@ -3339,7 +3339,7 @@ readCommandResponse(CState *st, MetaCommand meta, char *varprefix) /* anything else is unexpected */ pg_log_error("client %d script %d aborted in command %d query %d: %s", st->id, st->use_file, st->command, qrynum, - PQerrorMessage(st->con)); + PQresultErrorMessage(res)); goto error; } -- 2.47.3