v3-0001-pgbench-Ensure-previous-progress-message-is-fully.patch

From 7f0d10e9c2c65527fbb01acd777366d00596e72c Mon Sep 17 00:00:00 2001
From: Fujii Masao <fujii@postgresql.org>
Date: Fri, 8 Nov 2024 00:34:55 +0900
Subject: [PATCH v3] pgbench: Ensure previous progress message is fully cleared
 when updating.

During pgbench's table initialization, progress updates could display
leftover characters from the previous message if the new message
was shorter. This commit resolves the issue by appending spaces to
the current message to fully overwrite any remaining characters from
the previous line.

Back-patch to all the supported versions.

Author: Yushi Ogiwara, Tatsuo Ishii, Fujii Masao
Reviewed-by: Tatsuo Ishii, Fujii Masao
Discussion: https://postgr.es/m/9a9b8b95b6a709877ae48ad5b0c59bb9@oss.nttdata.com
---
 src/bin/pgbench/pgbench.c | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index ba247f3f85..19a82244b5 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -4944,6 +4944,7 @@ initPopulateTable(PGconn *con, const char *table, int64 base,
 	int			n;
 	int64		k;
 	int			chars = 0;
+	int			prev_chars = 0;
 	PGresult   *res;
 	PQExpBufferData sql;
 	char		copy_statement[256];
@@ -5004,10 +5005,10 @@ initPopulateTable(PGconn *con, const char *table, int64 base,
 			double		elapsed_sec = PG_TIME_GET_DOUBLE(pg_time_now() - start);
 			double		remaining_sec = ((double) total - j) * elapsed_sec / j;
 
-			chars = fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) of %s done (elapsed %.2f s, remaining %.2f s)%c",
+			chars = fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) of %s done (elapsed %.2f s, remaining %.2f s)",
 							j, total,
 							(int) ((j * 100) / total),
-							table, elapsed_sec, remaining_sec, eol);
+							table, elapsed_sec, remaining_sec);
 		}
 		/* let's not call the timing for each row, but only each 100 rows */
 		else if (use_quiet && (j % 100 == 0))
@@ -5018,15 +5019,25 @@ initPopulateTable(PGconn *con, const char *table, int64 base,
 			/* have we reached the next interval (or end)? */
 			if ((j == total) || (elapsed_sec >= log_interval * LOG_STEP_SECONDS))
 			{
-				chars = fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) of %s done (elapsed %.2f s, remaining %.2f s)%c",
+				chars = fprintf(stderr, INT64_FORMAT " of " INT64_FORMAT " tuples (%d%%) of %s done (elapsed %.2f s, remaining %.2f s)",
 								j, total,
 								(int) ((j * 100) / total),
-								table, elapsed_sec, remaining_sec, eol);
+								table, elapsed_sec, remaining_sec);
 
 				/* skip to the next interval */
 				log_interval = (int) ceil(elapsed_sec / LOG_STEP_SECONDS);
 			}
 		}
+
+		/*
+		 * If the previous progress message is longer than the current one,
+		 * add spaces to the current line to fully overwrite any remaining
+		 * characters from the previous message.
+		 */
+		if (prev_chars > chars)
+			fprintf(stderr, "%*c", prev_chars - chars, ' ');
+		fputc(eol, stderr);
+		prev_chars = chars;
 	}
 
 	if (chars != 0 && eol != '\n')
-- 
2.47.0