*** a/doc/src/sgml/pltcl.sgml
--- b/doc/src/sgml/pltcl.sgml
***************
*** 711,716 **** CREATE TRIGGER trig_mytab_modcount BEFORE INSERT OR UPDATE ON mytab
--- 711,770 ----
+
+ Event Trigger Procedures in PL/Tcl
+
+
+ event trigger
+ in PL/Tcl
+
+
+
+ Event trigger procedures can be written in PL/Tcl.
+ PostgreSQL requires that a procedure that is
+ to be called as an event trigger must be declared as a function with no
+ arguments and a return type of event_trigger.
+
+
+ The information from the trigger manager is passed to the procedure body
+ in the following variables:
+
+
+
+
+ $TG_event
+
+
+ The name of the event the trigger is fired for.
+
+
+
+
+
+ $TG_tag
+
+
+ The command tag for which the trigger is fired.
+
+
+
+
+
+
+ Here's a little example event trigger procedure that simply raises
+ a NOTICE message each time a supported command is
+ executed:
+
+
+ CREATE OR REPLACE FUNCTION tclsnitch() RETURNS event_trigger AS $$
+ elog NOTICE "tclsnitch: $TG_event $TG_tag"
+ $$ LANGUAGE PLTCL;
+
+ CREATE EVENT TRIGGER tcl_a_snitch ON ddl_command_start EXECUTE PROCEDURE tclsnitch();
+
+
+
+
Modules and the <function>unknown</> Command
*** a/src/pl/tcl/expected/pltcl_setup.out
--- b/src/pl/tcl/expected/pltcl_setup.out
***************
*** 519,521 **** select tcl_date_week(2001,10,24);
--- 519,544 ----
42
(1 row)
+ -- test pltcl event triggers
+ create or replace function tclsnitch() returns event_trigger language pltcl as $$
+ elog NOTICE " tclsnitch: $TG_event $TG_tag"
+ $$;
+ create event trigger tcl_a_snitch on ddl_command_start execute procedure tclsnitch();
+ create event trigger tcl_b_snitch on ddl_command_end execute procedure tclsnitch();
+ create or replace function foobar() returns int language sql as $$select 1;$$;
+ NOTICE: tclsnitch: ddl_command_start CREATE FUNCTION
+ NOTICE: tclsnitch: ddl_command_end CREATE FUNCTION
+ alter function foobar() cost 77;
+ NOTICE: tclsnitch: ddl_command_start ALTER FUNCTION
+ NOTICE: tclsnitch: ddl_command_end ALTER FUNCTION
+ drop function foobar();
+ NOTICE: tclsnitch: ddl_command_start DROP FUNCTION
+ NOTICE: tclsnitch: ddl_command_end DROP FUNCTION
+ create table foo();
+ NOTICE: tclsnitch: ddl_command_start CREATE TABLE
+ NOTICE: tclsnitch: ddl_command_end CREATE TABLE
+ drop table foo;
+ NOTICE: tclsnitch: ddl_command_start DROP TABLE
+ NOTICE: tclsnitch: ddl_command_end DROP TABLE
+ drop event trigger tcl_a_snitch;
+ drop event trigger tcl_b_snitch;
*** a/src/pl/tcl/pltcl.c
--- b/src/pl/tcl/pltcl.c
***************
*** 27,32 ****
--- 27,33 ----
#include "access/xact.h"
#include "catalog/pg_proc.h"
#include "catalog/pg_type.h"
+ #include "commands/event_trigger.h"
#include "commands/trigger.h"
#include "executor/spi.h"
#include "fmgr.h"
***************
*** 200,210 **** static Datum pltcl_handler(PG_FUNCTION_ARGS, bool pltrusted);
static Datum pltcl_func_handler(PG_FUNCTION_ARGS, bool pltrusted);
static HeapTuple pltcl_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted);
static void throw_tcl_error(Tcl_Interp *interp, const char *proname);
static pltcl_proc_desc *compile_pltcl_function(Oid fn_oid, Oid tgreloid,
! bool pltrusted);
static int pltcl_elog(ClientData cdata, Tcl_Interp *interp,
int argc, CONST84 char *argv[]);
--- 201,213 ----
static Datum pltcl_func_handler(PG_FUNCTION_ARGS, bool pltrusted);
static HeapTuple pltcl_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted);
+ static void pltcl_event_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted);
static void throw_tcl_error(Tcl_Interp *interp, const char *proname);
static pltcl_proc_desc *compile_pltcl_function(Oid fn_oid, Oid tgreloid,
! bool is_event_trigger,
! bool pltrusted);
static int pltcl_elog(ClientData cdata, Tcl_Interp *interp,
int argc, CONST84 char *argv[]);
***************
*** 644,649 **** pltcl_handler(PG_FUNCTION_ARGS, bool pltrusted)
--- 647,658 ----
pltcl_current_fcinfo = NULL;
retval = PointerGetDatum(pltcl_trigger_handler(fcinfo, pltrusted));
}
+ else if (CALLED_AS_EVENT_TRIGGER(fcinfo))
+ {
+ pltcl_current_fcinfo = NULL;
+ pltcl_event_trigger_handler(fcinfo, pltrusted);
+ retval = (Datum) 0;
+ }
else
{
pltcl_current_fcinfo = fcinfo;
***************
*** 685,691 **** pltcl_func_handler(PG_FUNCTION_ARGS, bool pltrusted)
/* Find or compile the function */
prodesc = compile_pltcl_function(fcinfo->flinfo->fn_oid, InvalidOid,
! pltrusted);
pltcl_current_prodesc = prodesc;
--- 694,700 ----
/* Find or compile the function */
prodesc = compile_pltcl_function(fcinfo->flinfo->fn_oid, InvalidOid,
! false, pltrusted);
pltcl_current_prodesc = prodesc;
***************
*** 844,849 **** pltcl_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted)
--- 853,859 ----
/* Find or compile the function */
prodesc = compile_pltcl_function(fcinfo->flinfo->fn_oid,
RelationGetRelid(trigdata->tg_relation),
+ false, /* not a event trigger */
pltrusted);
pltcl_current_prodesc = prodesc;
***************
*** 1130,1135 **** pltcl_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted)
--- 1140,1188 ----
return rettup;
}
+ /**********************************************************************
+ * pltcl_event_trigger_handler() - Handler for event trigger calls
+ **********************************************************************/
+ static void
+ pltcl_event_trigger_handler(PG_FUNCTION_ARGS, bool pltrusted)
+ {
+ pltcl_proc_desc *prodesc;
+ Tcl_Interp *volatile interp;
+ EventTriggerData *tdata = (EventTriggerData *) fcinfo->context;
+ Tcl_DString tcl_cmd;
+ int tcl_rc;
+
+ /* Connect to SPI manager */
+ if (SPI_connect() != SPI_OK_CONNECT)
+ elog(ERROR, "could not connect to SPI manager");
+
+ /* Find or compile the function */
+ prodesc = compile_pltcl_function(fcinfo->flinfo->fn_oid,
+ InvalidOid, true, pltrusted);
+
+ pltcl_current_prodesc = prodesc;
+
+ interp = prodesc->interp_desc->interp;
+
+ /* Create the tcl command and call the internal proc */
+ Tcl_DStringInit(&tcl_cmd);
+ Tcl_DStringAppendElement(&tcl_cmd, prodesc->internal_proname);
+ Tcl_DStringAppendElement(&tcl_cmd, tdata->event);
+ Tcl_DStringAppendElement(&tcl_cmd, tdata->tag);
+
+ tcl_rc = Tcl_GlobalEval(interp, Tcl_DStringValue(&tcl_cmd));
+ Tcl_DStringFree(&tcl_cmd);
+
+ /* Check for errors reported by Tcl. */
+ if (tcl_rc != TCL_OK)
+ throw_tcl_error(interp, prodesc->user_proname);
+
+ if (SPI_finish() != SPI_OK_FINISH)
+ elog(ERROR, "SPI_finish() failed");
+
+ return;
+ }
+
/**********************************************************************
* throw_tcl_error - ereport an error returned from the Tcl interpreter
***************
*** 1168,1174 **** throw_tcl_error(Tcl_Interp *interp, const char *proname)
* (InvalidOid) when compiling a plain function.
**********************************************************************/
static pltcl_proc_desc *
! compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
{
HeapTuple procTup;
Form_pg_proc procStruct;
--- 1221,1228 ----
* (InvalidOid) when compiling a plain function.
**********************************************************************/
static pltcl_proc_desc *
! compile_pltcl_function(Oid fn_oid, Oid tgreloid,
! bool is_event_trigger, bool pltrusted)
{
HeapTuple procTup;
Form_pg_proc procStruct;
***************
*** 1245,1254 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
* "_trigger" when appropriate to ensure the normal and trigger
* cases are kept separate.
************************************************************/
! if (!is_trigger)
snprintf(internal_proname, sizeof(internal_proname),
"__PLTcl_proc_%u", fn_oid);
! else
snprintf(internal_proname, sizeof(internal_proname),
"__PLTcl_proc_%u_trigger", fn_oid);
--- 1299,1311 ----
* "_trigger" when appropriate to ensure the normal and trigger
* cases are kept separate.
************************************************************/
! if (!is_trigger && !is_event_trigger)
snprintf(internal_proname, sizeof(internal_proname),
"__PLTcl_proc_%u", fn_oid);
! else if (is_event_trigger)
! snprintf(internal_proname, sizeof(internal_proname),
! "__PLTcl_proc_%u_evttrigger", fn_oid);
! else if (is_trigger)
snprintf(internal_proname, sizeof(internal_proname),
"__PLTcl_proc_%u_trigger", fn_oid);
***************
*** 1286,1292 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
* Get the required information for input conversion of the
* return value.
************************************************************/
! if (!is_trigger)
{
typeTup =
SearchSysCache1(TYPEOID,
--- 1343,1349 ----
* Get the required information for input conversion of the
* return value.
************************************************************/
! if (!is_trigger && !is_event_trigger)
{
typeTup =
SearchSysCache1(TYPEOID,
***************
*** 1306,1312 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
{
if (procStruct->prorettype == VOIDOID)
/* okay */ ;
! else if (procStruct->prorettype == TRIGGEROID)
{
free(prodesc->user_proname);
free(prodesc->internal_proname);
--- 1363,1370 ----
{
if (procStruct->prorettype == VOIDOID)
/* okay */ ;
! else if (procStruct->prorettype == TRIGGEROID ||
! procStruct->prorettype == EVTTRIGGEROID)
{
free(prodesc->user_proname);
free(prodesc->internal_proname);
***************
*** 1347,1353 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
* Get the required information for output conversion
* of all procedure arguments
************************************************************/
! if (!is_trigger)
{
prodesc->nargs = procStruct->pronargs;
proc_internal_args[0] = '\0';
--- 1405,1411 ----
* Get the required information for output conversion
* of all procedure arguments
************************************************************/
! if (!is_trigger && !is_event_trigger)
{
prodesc->nargs = procStruct->pronargs;
proc_internal_args[0] = '\0';
***************
*** 1397,1408 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
ReleaseSysCache(typeTup);
}
}
! else
{
/* trigger procedure has fixed args */
strcpy(proc_internal_args,
"TG_name TG_relid TG_table_name TG_table_schema TG_relatts TG_when TG_level TG_op __PLTcl_Tup_NEW __PLTcl_Tup_OLD args");
}
/************************************************************
* Create the tcl command to define the internal
--- 1455,1471 ----
ReleaseSysCache(typeTup);
}
}
! else if (is_trigger)
{
/* trigger procedure has fixed args */
strcpy(proc_internal_args,
"TG_name TG_relid TG_table_name TG_table_schema TG_relatts TG_when TG_level TG_op __PLTcl_Tup_NEW __PLTcl_Tup_OLD args");
}
+ else if (is_event_trigger)
+ {
+ /* event trigger procedure has fixed args */
+ strcpy(proc_internal_args, "TG_event TG_tag");
+ }
/************************************************************
* Create the tcl command to define the internal
***************
*** 1422,1441 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
Tcl_DStringAppend(&proc_internal_body, "upvar #0 ", -1);
Tcl_DStringAppend(&proc_internal_body, internal_proname, -1);
Tcl_DStringAppend(&proc_internal_body, " GD\n", -1);
! if (!is_trigger)
! {
! for (i = 0; i < prodesc->nargs; i++)
! {
! if (prodesc->arg_is_rowtype[i])
! {
! snprintf(buf, sizeof(buf),
! "array set %d $__PLTcl_Tup_%d\n",
! i + 1, i + 1);
! Tcl_DStringAppend(&proc_internal_body, buf, -1);
! }
! }
! }
! else
{
Tcl_DStringAppend(&proc_internal_body,
"array set NEW $__PLTcl_Tup_NEW\n", -1);
--- 1485,1491 ----
Tcl_DStringAppend(&proc_internal_body, "upvar #0 ", -1);
Tcl_DStringAppend(&proc_internal_body, internal_proname, -1);
Tcl_DStringAppend(&proc_internal_body, " GD\n", -1);
! if (is_trigger)
{
Tcl_DStringAppend(&proc_internal_body,
"array set NEW $__PLTcl_Tup_NEW\n", -1);
***************
*** 1451,1456 **** compile_pltcl_function(Oid fn_oid, Oid tgreloid, bool pltrusted)
--- 1501,1523 ----
"}\n"
"unset i v\n\n", -1);
}
+ else if (is_event_trigger)
+ {
+ /* no argument support for event triggers */
+ }
+ else
+ {
+ for (i = 0; i < prodesc->nargs; i++)
+ {
+ if (prodesc->arg_is_rowtype[i])
+ {
+ snprintf(buf, sizeof(buf),
+ "array set %d $__PLTcl_Tup_%d\n",
+ i + 1, i + 1);
+ Tcl_DStringAppend(&proc_internal_body, buf, -1);
+ }
+ }
+ }
/************************************************************
* Add user's function definition to proc body
*** a/src/pl/tcl/sql/pltcl_setup.sql
--- b/src/pl/tcl/sql/pltcl_setup.sql
***************
*** 559,561 **** $$ language pltcl immutable;
--- 559,579 ----
select tcl_date_week(2010,1,24);
select tcl_date_week(2001,10,24);
+
+ -- test pltcl event triggers
+ create or replace function tclsnitch() returns event_trigger language pltcl as $$
+ elog NOTICE " tclsnitch: $TG_event $TG_tag"
+ $$;
+
+ create event trigger tcl_a_snitch on ddl_command_start execute procedure tclsnitch();
+ create event trigger tcl_b_snitch on ddl_command_end execute procedure tclsnitch();
+
+ create or replace function foobar() returns int language sql as $$select 1;$$;
+ alter function foobar() cost 77;
+ drop function foobar();
+
+ create table foo();
+ drop table foo;
+
+ drop event trigger tcl_a_snitch;
+ drop event trigger tcl_b_snitch;