1 files changed, 122 insertions, 0 deletions
diff --git a/src/backend/nodes/params.c b/src/backend/nodes/params.c
new file mode 100644
index 00000000000..43bc40b9e1c
--- /dev/null
+++ b/src/backend/nodes/params.c
@@ -0,0 +1,122 @@
+/*-------------------------------------------------------------------------
+ *
+ * params.c
+ *	  Support functions for plan parameter lists.
+ *
+ * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *	  $PostgreSQL: pgsql/src/backend/nodes/params.c,v 1.1 2004/08/02 01:30:42 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "nodes/params.h"
+#include "utils/datum.h"
+#include "utils/lsyscache.h"
+
+
+/*
+ * Copy a ParamList.
+ *
+ * The result is allocated in CurrentMemoryContext.
+ */
+ParamListInfo
+copyParamList(ParamListInfo from)
+{
+	ParamListInfo retval;
+	int i, size;
+
+	if (from == NULL)
+		return NULL;
+
+	size = 0;
+	while (from[size].kind != PARAM_INVALID)
+		size++;
+
+	retval = (ParamListInfo) palloc0((size + 1) * sizeof(ParamListInfoData));
+
+	for (i = 0; i < size; i++) {
+		/* copy metadata */
+		retval[i].kind = from[i].kind;
+		if (from[i].kind == PARAM_NAMED)
+			retval[i].name = pstrdup(from[i].name);
+		retval[i].id = from[i].id;
+		retval[i].ptype = from[i].ptype;
+
+		/* copy value */
+		retval[i].isnull = from[i].isnull;
+		if (from[i].isnull)
+		{
+			retval[i].value = from[i].value; /* nulls just copy */
+		}
+		else
+		{
+			int16 typLen;
+			bool  typByVal;
+
+			get_typlenbyval(from[i].ptype, &typLen, &typByVal);
+			retval[i].value = datumCopy(from[i].value, typByVal, typLen);
+		}
+	}
+
+	retval[size].kind = PARAM_INVALID;
+
+	return retval;
+}
+
+/*
+ * Search a ParamList for a given parameter.
+ *
+ * On success, returns a pointer to the parameter's entry.
+ * On failure, returns NULL if noError is true, else ereports the error.
+ */
+ParamListInfo
+lookupParam(ParamListInfo paramList, int thisParamKind,
+			const char *thisParamName, AttrNumber thisParamId,
+			bool noError)
+{
+	if (paramList != NULL)
+	{
+		while (paramList->kind != PARAM_INVALID)
+		{
+			if (thisParamKind == paramList->kind)
+			{
+				switch (thisParamKind)
+				{
+					case PARAM_NAMED:
+						if (strcmp(paramList->name, thisParamName) == 0)
+							return paramList;
+						break;
+					case PARAM_NUM:
+						if (paramList->id == thisParamId)
+							return paramList;
+						break;
+					default:
+						elog(ERROR, "unrecognized paramkind: %d",
+							 thisParamKind);
+				}
+			}
+			paramList++;
+		}
+	}
+
+	if (!noError)
+	{
+		if (thisParamKind == PARAM_NAMED)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("no value found for parameter \"%s\"",
+							thisParamName)));
+		else
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("no value found for parameter %d",
+							thisParamId)));
+	}
+
+	return NULL;
+}