postgres.git / summary / log / commit / refs

commit    2a23dbcf35946b844699c65fdf2ee440251eab12
Author:   Tom Lane <tgl@sss.pgh.pa.us>
Date:     Sun Dec 15 19:14:15 2024 +0000

    pgbench: fix misprocessing of some nested \if constructs.
    
    An \if command appearing within a false (not-to-be-executed) \if
    branch was incorrectly treated the same as \elif.  This could allow
    statements within the inner \if to be executed when they should
    not be.  Also the missing inner \if stack entry would result in an
    assertion failure (in assert-enabled builds) when the final \endif
    is reached.
    
    Report and patch by Michail Nikolaev.  Back-patch to all
    supported branches.
    
    Discussion: https://postgr.es/m/CANtu0oiA1ke=SP6tauhNqkUdv5QFsJtS1p=aOOf_iU+EhyKkjQ@mail.gmail.com


 src/bin/pgbench/pgbench.c                    | 16 +++++----
 src/bin/pgbench/t/001_pgbench_with_server.pl | 50 ++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 7 deletions(-)

diff --git a/src/bin/pgbench/pgbench.c b/src/bin/pgbench/pgbench.c
index c7f8431841a..1f6cb0e6038 100644
--- a/src/bin/pgbench/pgbench.c
+++ b/src/bin/pgbench/pgbench.c
@@ -3446,8 +3446,14 @@ advanceConnectionState(TState *thread, CState *st, StatsData *agg)
 						switch (conditional_stack_peek(st->cstack))
 						{
 							case IFSTATE_FALSE:
-								if (command->meta == META_IF ||
-									command->meta == META_ELIF)
+								if (command->meta == META_IF)
+								{
+									/* nested if in skipped branch - ignore */
+									conditional_stack_push(st->cstack,
+														   IFSTATE_IGNORED);
+									st->command++;
+								}
+								else if (command->meta == META_ELIF)
 								{
 									/* we must evaluate the condition */
 									st->state = CSTATE_START_COMMAND;
@@ -3466,11 +3472,7 @@ advanceConnectionState(TState *thread, CState *st, StatsData *agg)
 									conditional_stack_pop(st->cstack);
 									if (conditional_active(st->cstack))
 										st->state = CSTATE_START_COMMAND;
-
-									/*
-									 * else state remains in
-									 * CSTATE_SKIP_COMMAND
-									 */
+									/* else state remains CSTATE_SKIP_COMMAND */
 									st->command++;
 								}
 								break;
diff --git a/src/bin/pgbench/t/001_pgbench_with_server.pl b/src/bin/pgbench/t/001_pgbench_with_server.pl
index 4f716c6c073..fbd45c766cc 100644
--- a/src/bin/pgbench/t/001_pgbench_with_server.pl
+++ b/src/bin/pgbench/t/001_pgbench_with_server.pl
@@ -622,6 +622,56 @@ SELECT :v0, :v1, :v2, :v3;
 }
 	});
 
+# test nested \if constructs
+$node->pgbench(
+	'--no-vacuum --client=1 --transactions=1',
+	0,
+	[qr{actually processed}],
+	[qr{^$}],
+	'nested ifs',
+	{
+		'pgbench_nested_if' => q(
+			\if false
+				SELECT 1 / 0;
+				\if true
+					SELECT 1 / 0;
+				\elif true
+					SELECT 1 / 0;
+				\else
+					SELECT 1 / 0;
+				\endif
+				SELECT 1 / 0;
+			\elif false
+				\if true
+					SELECT 1 / 0;
+				\elif true
+					SELECT 1 / 0;
+				\else
+					SELECT 1 / 0;
+				\endif
+			\else
+				\if false
+					SELECT 1 / 0;
+				\elif false
+					SELECT 1 / 0;
+				\else
+					SELECT 'correct';
+				\endif
+			\endif
+			\if true
+				SELECT 'correct';
+			\else
+				\if true
+					SELECT 1 / 0;
+				\elif true
+					SELECT 1 / 0;
+				\else
+					SELECT 1 / 0;
+				\endif
+			\endif
+		)
+	});
+
 # random determinism when seeded
 $node->safe_psql('postgres',
 	'CREATE UNLOGGED TABLE seeded_random(seed INT8 NOT NULL, rand TEXT NOT NULL, val INTEGER NOT NULL);'


[parent: c7f3c414fded]