1 files changed, 55 insertions, 27 deletions

diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
index e7eeb2df015..111276c348c 100644
--- a/src/backend/nodes/params.c
+++ b/src/backend/nodes/params.c
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1994, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/nodes/params.c,v 1.11 2009/01/01 17:23:43 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/nodes/params.c,v 1.12 2009/11/04 22:26:06 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -16,6 +16,7 @@
 #include "postgres.h"
 
 #include "nodes/params.h"
+#include "parser/parse_param.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"
 
@@ -24,6 +25,11 @@
  * Copy a ParamListInfo structure.
  *
  * The result is allocated in CurrentMemoryContext.
+ *
+ * Note: the intent of this function is to make a static, self-contained
+ * set of parameter values.  If dynamic parameter hooks are present, we
+ * intentionally do not copy them into the result.  Rather, we forcibly
+ * instantiate all available parameter values and copy the datum values.
  */
 ParamListInfo
 copyParamList(ParamListInfo from)
@@ -40,54 +46,76 @@ copyParamList(ParamListInfo from)
 		(from->numParams - 1) *sizeof(ParamExternData);
 
 	retval = (ParamListInfo) palloc(size);
-	memcpy(retval, from, size);
+	retval->paramFetch = NULL;
+	retval->paramFetchArg = NULL;
+	retval->parserSetup = NULL;
+	retval->parserSetupArg = NULL;
+	retval->numParams = from->numParams;
 
-	/*
-	 * Flat-copy is not good enough for pass-by-ref data values, so make a
-	 * pass over the array to copy those.
-	 */
-	for (i = 0; i < retval->numParams; i++)
+	for (i = 0; i < from->numParams; i++)
 	{
-		ParamExternData *prm = &retval->params[i];
+		ParamExternData *oprm = &from->params[i];
+		ParamExternData *nprm = &retval->params[i];
 		int16		typLen;
 		bool		typByVal;
 
-		if (prm->isnull || !OidIsValid(prm->ptype))
+		/* give hook a chance in case parameter is dynamic */
+		if (!OidIsValid(oprm->ptype) && from->paramFetch != NULL)
+			(*from->paramFetch) (from, i+1);
+
+		/* flat-copy the parameter info */
+		*nprm = *oprm;
+
+		/* need datumCopy in case it's a pass-by-reference datatype */
+		if (nprm->isnull || !OidIsValid(nprm->ptype))
 			continue;
-		get_typlenbyval(prm->ptype, &typLen, &typByVal);
-		prm->value = datumCopy(prm->value, typByVal, typLen);
+		get_typlenbyval(nprm->ptype, &typLen, &typByVal);
+		nprm->value = datumCopy(nprm->value, typByVal, typLen);
 	}
 
 	return retval;
 }
 
 /*
- * Extract an array of parameter type OIDs from a ParamListInfo.
+ * Set up the parser to treat the given list of run-time parameters
+ * as available external parameters during parsing of a new query.
  *
- * The result is allocated in CurrentMemoryContext.
+ * Note that the parser doesn't actually care about the *values* of the given
+ * parameters, only about their *types*.  Also, the code that originally
+ * provided the ParamListInfo may have provided a setupHook, which should
+ * override applying parse_fixed_parameters().
  */
 void
-getParamListTypes(ParamListInfo params,
-				  Oid **param_types, int *num_params)
+setupParserWithParamList(struct ParseState *pstate,
+						 ParamListInfo params)
 {
-	Oid		   *ptypes;
-	int			i;
+	if (params == NULL)			/* no params, nothing to do */
+		return;
 
-	if (params == NULL || params->numParams <= 0)
+	/* If there is a parserSetup hook, it gets to do this */
+	if (params->parserSetup != NULL)
 	{
-		*param_types = NULL;
-		*num_params = 0;
+		(*params->parserSetup) (pstate, params->parserSetupArg);
 		return;
 	}
 
-	ptypes = (Oid *) palloc(params->numParams * sizeof(Oid));
-	*param_types = ptypes;
-	*num_params = params->numParams;
-
-	for (i = 0; i < params->numParams; i++)
+	/* Else, treat any available parameters as being of fixed type */
+	if (params->numParams > 0)
 	{
-		ParamExternData *prm = &params->params[i];
+		Oid		   *ptypes;
+		int			i;
+
+		ptypes = (Oid *) palloc(params->numParams * sizeof(Oid));
+		for (i = 0; i < params->numParams; i++)
+		{
+			ParamExternData *prm = &params->params[i];
+
+			/* give hook a chance in case parameter is dynamic */
+			if (!OidIsValid(prm->ptype) && params->paramFetch != NULL)
+				(*params->paramFetch) (params, i+1);
 
-		ptypes[i] = prm->ptype;
+			ptypes[i] = prm->ptype;
+		}
+		parse_fixed_parameters(pstate, ptypes, params->numParams);
 	}
 }