From 96b0da67ff82268d6d2dc6eeabaa277ba4a2fab4 Mon Sep 17 00:00:00 2001 From: Tom Lane <tgl@sss.pgh.pa.us> Date: Mon, 25 Jan 2010 01:58:19 +0000 Subject: [PATCH] Apply Tcl_Init() to the "hold" interpreter created by pltcl. You might think this is unnecessary since that interpreter is never used to run code --- but it turns out that's wrong. As of Tcl 8.5, the "clock" command (alone among builtin Tcl commands) is partially implemented by loaded-on-demand Tcl code, which means that it fails if there's not unknown-command support, and also that it's impossible to run it directly in a safe interpreter. The way they get around the latter is that Tcl_CreateSlave() automatically sets up an alias command that forwards any execution of "clock" in a safe slave interpreter to its parent interpreter. Thus, when attempting to execute "clock" in trusted pltcl, the command actually executes in the "hold" interpreter, where it will fail if unknown-command support hasn't been introduced by sourcing the standard init.tcl script, which is done by Tcl_Init(). (This is a pretty dubious design decision on the Tcl boys' part, if you ask me ... but they didn't.) Back-patch all the way. It's not clear that anyone would try to use ancient versions of pltcl with a recent Tcl, but it's not clear they wouldn't, either. Also add a regression test using "clock", in branches that have regression test support for pltcl. Per recent trouble report from Kyle Bateman. --- src/pl/tcl/expected/pltcl_setup.out | 20 ++++++++++++++++++++ src/pl/tcl/pltcl.c | 7 +++++-- src/pl/tcl/sql/pltcl_setup.sql | 12 ++++++++++++ 3 files changed, 37 insertions(+), 2 deletions(-) diff --git a/src/pl/tcl/expected/pltcl_setup.out b/src/pl/tcl/expected/pltcl_setup.out index 496cf228dc..e46c1c3e98 100644 --- a/src/pl/tcl/expected/pltcl_setup.out +++ b/src/pl/tcl/expected/pltcl_setup.out @@ -495,3 +495,23 @@ CREATE OPERATOR CLASS tcl_int4_ops OPERATOR 4 @>=, OPERATOR 5 @>, FUNCTION 1 tcl_int4cmp(int4,int4) ; +-- +-- Test usage of Tcl's "clock" command. In recent Tcl versions this +-- command fails without working "unknown" support, so it's a good canary +-- for initialization problems. +-- +create function tcl_date_week(int4,int4,int4) returns text as $$ + return [clock format [clock scan "$2/$3/$1"] -format "%U"] +$$ language pltcl immutable; +select tcl_date_week(2010,1,24); + tcl_date_week +--------------- + 04 +(1 row) + +select tcl_date_week(2001,10,24); + tcl_date_week +--------------- + 42 +(1 row) + diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c index 2e8db71275..dfca5852f3 100644 --- a/src/pl/tcl/pltcl.c +++ b/src/pl/tcl/pltcl.c @@ -2,7 +2,7 @@ * pltcl.c - PostgreSQL support for Tcl as * procedural language (PL) * - * $PostgreSQL: pgsql/src/pl/tcl/pltcl.c,v 1.128 2009/06/11 14:49:14 momjian Exp $ + * $PostgreSQL: pgsql/src/pl/tcl/pltcl.c,v 1.128.2.1 2010/01/25 01:58:19 tgl Exp $ * **********************************************************************/ @@ -304,9 +304,12 @@ _PG_init(void) ************************************************************/ if ((pltcl_hold_interp = Tcl_CreateInterp()) == NULL) elog(ERROR, "could not create \"hold\" interpreter"); + if (Tcl_Init(pltcl_hold_interp) == TCL_ERROR) + elog(ERROR, "could not initialize \"hold\" interpreter"); /************************************************************ - * Create the two interpreters + * Create the two slave interpreters. Note: Tcl automatically does + * Tcl_Init on the normal slave, and it's not wanted for the safe slave. ************************************************************/ if ((pltcl_norm_interp = Tcl_CreateSlave(pltcl_hold_interp, "norm", 0)) == NULL) diff --git a/src/pl/tcl/sql/pltcl_setup.sql b/src/pl/tcl/sql/pltcl_setup.sql index 55ac7e20d5..4a581ed8b1 100644 --- a/src/pl/tcl/sql/pltcl_setup.sql +++ b/src/pl/tcl/sql/pltcl_setup.sql @@ -542,3 +542,15 @@ CREATE OPERATOR CLASS tcl_int4_ops OPERATOR 4 @>=, OPERATOR 5 @>, FUNCTION 1 tcl_int4cmp(int4,int4) ; + +-- +-- Test usage of Tcl's "clock" command. In recent Tcl versions this +-- command fails without working "unknown" support, so it's a good canary +-- for initialization problems. +-- +create function tcl_date_week(int4,int4,int4) returns text as $$ + return [clock format [clock scan "$2/$3/$1"] -format "%U"] +$$ language pltcl immutable; + +select tcl_date_week(2010,1,24); +select tcl_date_week(2001,10,24);