From 56f3fb3ba1aed1efbfb6b50e55159df8a0ad2f39 Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Mon, 27 Aug 2007 00:13:51 +0000
Subject: [PATCH] Restrict pgrowlocks function to superusers. (This might be
too strict, but no permissions check at all is certainly no good.) Clean up
usage of some deprecated APIs.
---
contrib/pgrowlocks/README.pgrowlocks | 14 +-----
contrib/pgrowlocks/pgrowlocks.c | 50 +++++++--------------
contrib/pgrowlocks/pgrowlocks.sql.in | 21 ++++-----
contrib/pgrowlocks/uninstall_pgrowlocks.sql | 2 -
4 files changed, 26 insertions(+), 61 deletions(-)
diff --git a/contrib/pgrowlocks/README.pgrowlocks b/contrib/pgrowlocks/README.pgrowlocks
index ebaea4ca5a3..6964cc9c73e 100644
--- a/contrib/pgrowlocks/README.pgrowlocks
+++ b/contrib/pgrowlocks/README.pgrowlocks
@@ -1,4 +1,4 @@
-$PostgreSQL: pgsql/contrib/pgrowlocks/README.pgrowlocks,v 1.1 2006/04/23 01:12:58 ishii Exp $
+$PostgreSQL: pgsql/contrib/pgrowlocks/README.pgrowlocks,v 1.2 2007/08/27 00:13:51 tgl Exp $
pgrowlocks README Tatsuo Ishii
@@ -6,16 +6,14 @@ pgrowlocks README Tatsuo Ishii
pgrowlocks shows row locking information for specified table.
- pgrowlocks returns following data type:
+ pgrowlocks returns following columns:
-CREATE TYPE pgrowlocks_type AS (
locked_row TID, -- row TID
lock_type TEXT, -- lock type
locker XID, -- locking XID
multi bool, -- multi XID?
xids xid[], -- multi XIDs
pids INTEGER[] -- locker's process id
-);
Here is a sample execution of pgrowlocks:
@@ -62,14 +60,6 @@ test=# SELECT * FROM pgrowlocks('t1');
3. How to use pgrowlocks
- The calling sequence for pgrowlocks is as follows:
-
- CREATE OR REPLACE FUNCTION pgrowlocks(text) RETURNS pgrowlocks_type
- AS 'MODULE_PATHNAME', 'pgrowlocks'
- LANGUAGE 'c' WITH (isstrict);
-
- The parameter is a name of table. pgrowlocks returns type pgrowlocks_type.
-
pgrowlocks grab AccessShareLock for the target table and read each
row one by one to get the row locking information. You should
notice that:
diff --git a/contrib/pgrowlocks/pgrowlocks.c b/contrib/pgrowlocks/pgrowlocks.c
index 002536b9201..73dea0c4a56 100644
--- a/contrib/pgrowlocks/pgrowlocks.c
+++ b/contrib/pgrowlocks/pgrowlocks.c
@@ -1,5 +1,5 @@
/*
- * $PostgreSQL: pgsql/contrib/pgrowlocks/pgrowlocks.c,v 1.5 2006/10/04 00:29:46 momjian Exp $
+ * $PostgreSQL: pgsql/contrib/pgrowlocks/pgrowlocks.c,v 1.6 2007/08/27 00:13:51 tgl Exp $
*
* Copyright (c) 2005-2006 Tatsuo Ishii
*
@@ -24,19 +24,15 @@
#include "postgres.h"
-#include "funcapi.h"
#include "access/heapam.h"
-#include "access/transam.h"
+#include "access/multixact.h"
#include "access/xact.h"
#include "catalog/namespace.h"
-#include "catalog/pg_type.h"
-#include "storage/proc.h"
+#include "funcapi.h"
+#include "miscadmin.h"
+#include "storage/procarray.h"
#include "utils/builtins.h"
-#ifdef HEAP_XMAX_SHARED_LOCK
-#include "access/multixact.h"
-#include "storage/procarray.h"
-#endif
PG_MODULE_MAGIC;
@@ -47,22 +43,11 @@ extern Datum pgrowlocks(PG_FUNCTION_ARGS);
/* ----------
* pgrowlocks:
* returns tids of rows being locked
- *
- * C FUNCTION definition
- * pgrowlocks(text) returns set of pgrowlocks_type
- * see pgrowlocks.sql for pgrowlocks_type
* ----------
*/
-#define DUMMY_TUPLE "public.pgrowlocks_type"
#define NCHARS 32
-/*
- * define this if makeRangeVarFromNameList() has two arguments. As far
- * as I know, this only happens in 8.0.x.
- */
-#undef MAKERANGEVARFROMNAMELIST_HAS_TWO_ARGS
-
typedef struct
{
Relation rel;
@@ -82,6 +67,11 @@ pgrowlocks(PG_FUNCTION_ARGS)
MyData *mydata;
Relation rel;
+ if (!superuser())
+ ereport(ERROR,
+ (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
+ (errmsg("must be superuser to use pgrowlocks"))));
+
if (SRF_IS_FIRSTCALL())
{
text *relname;
@@ -91,17 +81,17 @@ pgrowlocks(PG_FUNCTION_ARGS)
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
- tupdesc = RelationNameGetTupleDesc(DUMMY_TUPLE);
+ /* Build a tuple descriptor for our result type */
+ if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
+ elog(ERROR, "return type must be a row type");
+
attinmeta = TupleDescGetAttInMetadata(tupdesc);
funcctx->attinmeta = attinmeta;
relname = PG_GETARG_TEXT_P(0);
-#ifdef MAKERANGEVARFROMNAMELIST_HAS_TWO_ARGS
- relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname, "pgrowlocks"));
-#else
relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
-#endif
rel = heap_openrv(relrv, AccessShareLock);
+
scan = heap_beginscan(rel, SnapshotNow, 0, NULL);
mydata = palloc(sizeof(*mydata));
mydata->rel = rel;
@@ -135,17 +125,12 @@ pgrowlocks(PG_FUNCTION_ARGS)
i = 0;
values[i++] = (char *) DirectFunctionCall1(tidout, PointerGetDatum(&tuple->t_self));
-#ifdef HEAP_XMAX_SHARED_LOCK
if (tuple->t_data->t_infomask & HEAP_XMAX_SHARED_LOCK)
values[i++] = pstrdup("Shared");
else
values[i++] = pstrdup("Exclusive");
-#else
- values[i++] = pstrdup("Exclusive");
-#endif
values[i] = palloc(NCHARS * sizeof(char));
snprintf(values[i++], NCHARS, "%d", HeapTupleHeaderGetXmax(tuple->t_data));
-#ifdef HEAP_XMAX_SHARED_LOCK
if (tuple->t_data->t_infomask & HEAP_XMAX_IS_MULTI)
{
TransactionId *xids;
@@ -198,11 +183,6 @@ pgrowlocks(PG_FUNCTION_ARGS)
values[i] = palloc(NCHARS * sizeof(char));
snprintf(values[i++], NCHARS, "{%d}", BackendXidGetPid(HeapTupleHeaderGetXmax(tuple->t_data)));
}
-#else
- values[i++] = pstrdup("false");
- values[i++] = pstrdup("{}");
- values[i++] = pstrdup("{}");
-#endif
LockBuffer(scan->rs_cbuf, BUFFER_LOCK_UNLOCK);
diff --git a/contrib/pgrowlocks/pgrowlocks.sql.in b/contrib/pgrowlocks/pgrowlocks.sql.in
index 0607c443490..0370831e66a 100644
--- a/contrib/pgrowlocks/pgrowlocks.sql.in
+++ b/contrib/pgrowlocks/pgrowlocks.sql.in
@@ -1,16 +1,13 @@
-- Adjust this setting to control where the objects get created.
SET search_path = public;
-CREATE TYPE pgrowlocks_type AS (
- locked_row TID, -- row TID
- lock_type TEXT, -- lock type
- locker XID, -- locking XID
- multi bool, -- multi XID?
- xids xid[], -- multi XIDs
- pids INTEGER[] -- locker's process id
-);
-
-CREATE OR REPLACE FUNCTION pgrowlocks(text)
-RETURNS setof pgrowlocks_type
+CREATE OR REPLACE FUNCTION pgrowlocks(IN relname text,
+ OUT locked_row TID, -- row TID
+ OUT lock_type TEXT, -- lock type
+ OUT locker XID, -- locking XID
+ OUT multi bool, -- multi XID?
+ OUT xids xid[], -- multi XIDs
+ OUT pids INTEGER[]) -- locker's process id
+RETURNS SETOF record
AS 'MODULE_PATHNAME', 'pgrowlocks'
-LANGUAGE 'C' STRICT;
+LANGUAGE C STRICT;
diff --git a/contrib/pgrowlocks/uninstall_pgrowlocks.sql b/contrib/pgrowlocks/uninstall_pgrowlocks.sql
index 9e37d119755..b1a1f58b52d 100644
--- a/contrib/pgrowlocks/uninstall_pgrowlocks.sql
+++ b/contrib/pgrowlocks/uninstall_pgrowlocks.sql
@@ -1,5 +1,3 @@
SET search_path = public;
DROP FUNCTION pgrowlocks(text);
-
-DROP TYPE pgrowlocks_type;
--
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