The following bug has been logged online:
Bug reference: 1259
Logged by: Vadim Passynkov
Email address: Vadim.Passynkov@pathcom.com
PostgreSQL version: 7.4.5
Operating system: FreeBSD 4.10-STABLE
Description: garbage in pg_listener after backend crash
Details:
If current backend crash after registers on the notification condition
<name> ( 'LISTEN <name>' SQL command ) row in the pg_listener still exists;
======================================================
template1=# SELECT pg_backend_pid ();
pg_backend_pid
----------------
6312
(1 row)
template1=# LISTEN test;
LISTEN
template1=# SELECT * from pg_listener where listenerpid = 6312;
relname | listenerpid | notification
---------+-------------+--------------
test | 6312 | 0
(1 row)
template1=# SELECT crash_backend ( );
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!> \c template1 pgsql
You are now connected to database "template1" as user "pgsql".
template1=# SELECT * from pg_listener where listenerpid = 6312;
relname | listenerpid | notification
---------+-------------+--------------
test | 6312 | 0
(1 row)
======================================================
/* crash_backend.c */
#include "postgres.h"
#include "executor/spi.h"
PG_FUNCTION_INFO_V1 ( crash_backend );
Datum crash_backend ( PG_FUNCTION_ARGS ) {
char *ptr = NULL;
*ptr = '1';
PG_RETURN_INT32 ( 1 );
}
======================================================
cc -Wall -fpic -I/usr/local/include/postgresql/server -I/usr/local/include
-c crash_backend.c -o crash_backend.o
cc -shared -o crash_backend.so crash_backend.o
======================================================
CREATE OR REPLACE FUNCTION crash_backend ( ) RETURNS integer AS
'/usr/home/pvi/pg_bug/crash_backend.so', 'crash_backend' LANGUAGE 'C';
======================================================
--
Vadim Passynkov