From ccbbb268374074f767b6cb2daa7124ca7ec3df6b Mon Sep 17 00:00:00 2001
From: Greg Sabino Mullane <greg@turnstep.com>
Date: Fri, 23 Aug 2024 09:36:35 -0400
Subject: [PATCH v2 1/4] Add new initdb argument "--no-data-checksums" to force
 checksums off

---
 doc/src/sgml/ref/initdb.sgml   |  9 +++++++++
 src/bin/initdb/initdb.c        |  5 +++++
 src/bin/initdb/t/001_initdb.pl | 12 ++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/doc/src/sgml/ref/initdb.sgml b/doc/src/sgml/ref/initdb.sgml
index bdd613e77f..a854b32e54 100644
--- a/doc/src/sgml/ref/initdb.sgml
+++ b/doc/src/sgml/ref/initdb.sgml
@@ -277,6 +277,15 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry id="app-initdb-no-data-checksums" xreflabel="no data checksums">
+      <term><option>--no-data-checksums</option></term>
+      <listitem>
+       <para>
+        Prevents initdb from enabling data checksums.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry id="app-initdb-option-locale">
       <term><option>--locale=<replaceable>locale</replaceable></option></term>
       <listitem>
diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c
index f00718a015..1f36e59286 100644
--- a/src/bin/initdb/initdb.c
+++ b/src/bin/initdb/initdb.c
@@ -2456,6 +2456,7 @@ usage(const char *progname)
 	printf(_("      --icu-locale=LOCALE   set ICU locale ID for new databases\n"));
 	printf(_("      --icu-rules=RULES     set additional ICU collation rules for new databases\n"));
 	printf(_("  -k, --data-checksums      use data page checksums\n"));
+	printf(_("      --no-data-checksums   do not use data page checksums\n"));
 	printf(_("      --locale=LOCALE       set default locale for new databases\n"));
 	printf(_("      --lc-collate=, --lc-ctype=, --lc-messages=LOCALE\n"
 			 "      --lc-monetary=, --lc-numeric=, --lc-time=LOCALE\n"
@@ -3121,6 +3122,7 @@ main(int argc, char *argv[])
 		{"waldir", required_argument, NULL, 'X'},
 		{"wal-segsize", required_argument, NULL, 12},
 		{"data-checksums", no_argument, NULL, 'k'},
+		{"no-data-checksums", no_argument, NULL, 20},
 		{"allow-group-access", no_argument, NULL, 'g'},
 		{"discard-caches", no_argument, NULL, 14},
 		{"locale-provider", required_argument, NULL, 15},
@@ -3319,6 +3321,9 @@ main(int argc, char *argv[])
 				if (!parse_sync_method(optarg, &sync_method))
 					exit(1);
 				break;
+			case 20:
+				data_checksums = false;
+				break;
 			default:
 				/* getopt_long already emitted a complaint */
 				pg_log_error_hint("Try \"%s --help\" for more information.", progname);
diff --git a/src/bin/initdb/t/001_initdb.pl b/src/bin/initdb/t/001_initdb.pl
index 06a35ac0b7..8072adb97f 100644
--- a/src/bin/initdb/t/001_initdb.pl
+++ b/src/bin/initdb/t/001_initdb.pl
@@ -268,4 +268,16 @@ ok($conf !~ qr/^WORK_MEM = /m, "WORK_MEM should not be configured");
 ok($conf !~ qr/^Work_Mem = /m, "Work_Mem should not be configured");
 ok($conf =~ qr/^work_mem = 512/m, "work_mem should be in config");
 
+# Test the no-data-checksums flag
+my $datadir_nochecksums = "$tempdir/data_no_checksums";
+
+command_ok([ 'initdb', '--no-data-checksums', $datadir_nochecksums ],
+	'successful creation without data checksums');
+
+# Control file should tell that data checksums are disabled.
+command_like(
+	[ 'pg_controldata', $datadir_nochecksums ],
+	qr/Data page checksum version:.*0/,
+	'checksums are disabled in control file');
+
 done_testing();
-- 
2.30.2