Make SPI_fnumber() reject dropped columns.

There's basically no scenario where it's sensible for this to match
dropped columns, so put a test for dropped-ness into SPI_fnumber()
itself, and excise the test from the small number of callers that
were paying attention to the case.  (Most weren't :-(.)

In passing, normalize tests at call sites: always reject attnum <= 0
if we're disallowing system columns.  Previously there was a mixture
of "< 0" and "<= 0" tests.  This makes no practical difference since
SPI_fnumber() never returns 0, but I'm feeling pedantic today.

Also, in the places that are actually live user-facing code and not
legacy cruft, distinguish "column not found" from "can't handle
system column".

Per discussion with Jim Nasby; thi supersedes his original patch
that just changed the behavior at one call site.

Discussion: <b2de8258-c4c0-1cb8-7b97-e8538e5c975c@BlueTreble.com>

1 files changed, 1 insertions, 10 deletions

diff --git a/src/pl/tcl/pltcl.c b/src/pl/tcl/pltcl.c
index 3e52113ee25..20809102efb 100644
--- a/src/pl/tcl/pltcl.c
+++ b/src/pl/tcl/pltcl.c
@@ -603,6 +603,7 @@ pltcl_init_load_unknown(Tcl_Interp *interp)
 	 * leave this code as DString - it's only executed once per session
 	 ************************************************************/
 	fno = SPI_fnumber(SPI_tuptable->tupdesc, "modsrc");
+	Assert(fno > 0);
 
 	Tcl_DStringInit(&unknown_src);
 
@@ -1260,12 +1261,6 @@ pltcl_trigger_handler(PG_FUNCTION_ARGS, pltcl_call_state *call_state,
 							ret_name)));
 
 		/************************************************************
-		 * Ignore dropped columns
-		 ************************************************************/
-		if (tupdesc->attrs[attnum - 1]->attisdropped)
-			continue;
-
-		/************************************************************
 		 * Lookup the attribute type's input function
 		 ************************************************************/
 		getTypeInputInfo(tupdesc->attrs[attnum - 1]->atttypid,
@@ -3077,10 +3072,6 @@ pltcl_build_tuple_result(Tcl_Interp *interp, Tcl_Obj **kvObjv, int kvObjc,
 					 errmsg("cannot set system attribute \"%s\"",
 							fieldName)));
 
-		/* Ignore dropped attributes */
-		if (call_state->ret_tupdesc->attrs[attn - 1]->attisdropped)
-			continue;
-
 		values[attn - 1] = utf_e2u(Tcl_GetString(kvObjv[i + 1]));
 	}