Modify all callers of datatype input and receive functions so that if these

functions are not strict, they will be called (passing a NULL first parameter)
during any attempt to input a NULL value of their datatype.  Currently, all
our input functions are strict and so this commit does not change any
behavior.  However, this will make it possible to build domain input functions
that centralize checking of domain constraints, thereby closing numerous holes
in our domain support, as per previous discussion.

While at it, I took the opportunity to introduce convenience functions
InputFunctionCall, OutputFunctionCall, etc to use in code that calls I/O
functions.  This eliminates a lot of grotty-looking casts, but the main
motivation is to make it easier to grep for these places if we ever need
to touch them again.

1 files changed, 23 insertions, 22 deletions

diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 23c057af8e0..af21d565f17 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.261 2006/03/23 00:19:29 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/copy.c,v 1.262 2006/04/04 19:35:33 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1382,8 +1382,8 @@ CopyTo(CopyState cstate)
 			{
 				if (!cstate->binary)
 				{
-					string = DatumGetCString(FunctionCall1(&out_functions[attnum - 1],
-														   value));
+					string = OutputFunctionCall(&out_functions[attnum - 1],
+												value);
 					if (cstate->csv_mode)
 						CopyAttributeOutCSV(cstate, string,
 											force_quote[attnum - 1],
@@ -1395,9 +1395,8 @@ CopyTo(CopyState cstate)
 				{
 					bytea	   *outputbytes;
 
-					outputbytes = DatumGetByteaP(FunctionCall1(&out_functions[attnum - 1],
-															   value));
-					/* We assume the result will not have been toasted */
+					outputbytes = SendFunctionCall(&out_functions[attnum - 1],
+												   value);
 					CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ);
 					CopySendData(cstate, VARDATA(outputbytes),
 								 VARSIZE(outputbytes) - VARHDRSZ);
@@ -1459,6 +1458,13 @@ copy_in_error_callback(void *arg)
 					   cstate->cur_attname, attval);
 			pfree(attval);
 		}
+		else if (cstate->cur_attname)
+		{
+			/* error is relevant to a particular column, value is NULL */
+			errcontext("COPY %s, line %d, column %s: NULL input",
+					   cstate->cur_relname, cstate->cur_lineno,
+					   cstate->cur_attname);
+		}
 		else
 		{
 			/* error is relevant to a particular line */
@@ -1854,19 +1860,16 @@ CopyFrom(CopyState cstate)
 					string = cstate->null_print;
 				}
 
-				/* If we read an SQL NULL, no need to do anything */
+				cstate->cur_attname = NameStr(attr[m]->attname);
+				cstate->cur_attval = string;
+				values[m] = InputFunctionCall(&in_functions[m],
+											  string,
+											  typioparams[m],
+											  attr[m]->atttypmod);
 				if (string != NULL)
-				{
-					cstate->cur_attname = NameStr(attr[m]->attname);
-					cstate->cur_attval = string;
-					values[m] = FunctionCall3(&in_functions[m],
-											  CStringGetDatum(string),
-											ObjectIdGetDatum(typioparams[m]),
-										  Int32GetDatum(attr[m]->atttypmod));
 					nulls[m] = ' ';
-					cstate->cur_attname = NULL;
-					cstate->cur_attval = NULL;
-				}
+				cstate->cur_attname = NULL;
+				cstate->cur_attval = NULL;
 			}
 
 			Assert(fieldno == nfields);
@@ -2900,7 +2903,7 @@ CopyReadBinaryAttribute(CopyState cstate,
 	if (fld_size == -1)
 	{
 		*isnull = true;
-		return (Datum) 0;
+		return ReceiveFunctionCall(flinfo, NULL, typioparam, typmod);
 	}
 	if (fld_size < 0)
 		ereport(ERROR,
@@ -2924,10 +2927,8 @@ CopyReadBinaryAttribute(CopyState cstate,
 	cstate->attribute_buf.data[fld_size] = '\0';
 
 	/* Call the column type's binary input converter */
-	result = FunctionCall3(flinfo,
-						   PointerGetDatum(&cstate->attribute_buf),
-						   ObjectIdGetDatum(typioparam),
-						   Int32GetDatum(typmod));
+	result = ReceiveFunctionCall(flinfo, &cstate->attribute_buf,
+								 typioparam, typmod);
 
 	/* Trouble if it didn't eat the whole buffer */
 	if (cstate->attribute_buf.cursor != cstate->attribute_buf.len)