Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n).

This is a mechanical change in preparation for a later commit that
will change the layout of TupleDesc.  Introducing a macro to abstract
the details of where attributes are stored will allow us to change
that in separate step and revise it in future.

Author: Thomas Munro, editorialized by Andres Freund
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com

Author: anarazel

contrib/dblink/dblink.c

@@ -2172,14 +2172,16 @@ get_sql_insert(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals
 	needComma = false;
 	for (i = 0; i < natts; i++)
 	{
-		if (tupdesc->attrs[i]->attisdropped)
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+
+		if (att->attisdropped)
 			continue;
 
 		if (needComma)
 			appendStringInfoChar(&buf, ',');
 
 		appendStringInfoString(&buf,
-							   quote_ident_cstr(NameStr(tupdesc->attrs[i]->attname)));
+							   quote_ident_cstr(NameStr(att->attname)));
 		needComma = true;
 	}
 
@@ -2191,7 +2193,7 @@ get_sql_insert(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals
 	needComma = false;
 	for (i = 0; i < natts; i++)
 	{
-		if (tupdesc->attrs[i]->attisdropped)
+		if (TupleDescAttr(tupdesc, i)->attisdropped)
 			continue;
 
 		if (needComma)
@@ -2237,12 +2239,13 @@ get_sql_delete(Relation rel, int *pkattnums, int pknumatts, char **tgt_pkattvals
 	for (i = 0; i < pknumatts; i++)
 	{
 		int			pkattnum = pkattnums[i];
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
 
 		if (i > 0)
 			appendStringInfoString(&buf, " AND ");
 
 		appendStringInfoString(&buf,
-							   quote_ident_cstr(NameStr(tupdesc->attrs[pkattnum]->attname)));
+							   quote_ident_cstr(NameStr(attr->attname)));
 
 		if (tgt_pkattvals[i] != NULL)
 			appendStringInfo(&buf, " = %s",
@@ -2289,14 +2292,16 @@ get_sql_update(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals
 	needComma = false;
 	for (i = 0; i < natts; i++)
 	{
-		if (tupdesc->attrs[i]->attisdropped)
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+
+		if (attr->attisdropped)
 			continue;
 
 		if (needComma)
 			appendStringInfoString(&buf, ", ");
 
 		appendStringInfo(&buf, "%s = ",
-						 quote_ident_cstr(NameStr(tupdesc->attrs[i]->attname)));
+						 quote_ident_cstr(NameStr(attr->attname)));
 
 		key = get_attnum_pk_pos(pkattnums, pknumatts, i);
 
@@ -2320,12 +2325,13 @@ get_sql_update(Relation rel, int *pkattnums, int pknumatts, char **src_pkattvals
 	for (i = 0; i < pknumatts; i++)
 	{
 		int			pkattnum = pkattnums[i];
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
 
 		if (i > 0)
 			appendStringInfoString(&buf, " AND ");
 
 		appendStringInfoString(&buf,
-							   quote_ident_cstr(NameStr(tupdesc->attrs[pkattnum]->attname)));
+							   quote_ident_cstr(NameStr(attr->attname)));
 
 		val = tgt_pkattvals[i];
 
@@ -2409,27 +2415,30 @@ get_tuple_of_interest(Relation rel, int *pkattnums, int pknumatts, char **src_pk
 
 	for (i = 0; i < natts; i++)
 	{
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, i);
+
 		if (i > 0)
 			appendStringInfoString(&buf, ", ");
 
-		if (tupdesc->attrs[i]->attisdropped)
+		if (attr->attisdropped)
 			appendStringInfoString(&buf, "NULL");
 		else
 			appendStringInfoString(&buf,
-								   quote_ident_cstr(NameStr(tupdesc->attrs[i]->attname)));
+								   quote_ident_cstr(NameStr(attr->attname)));
 	}
 
 	appendStringInfo(&buf, " FROM %s WHERE ", relname);
 
 	for (i = 0; i < pknumatts; i++)
 	{
 		int			pkattnum = pkattnums[i];
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, pkattnum);
 
 		if (i > 0)
 			appendStringInfoString(&buf, " AND ");
 
 		appendStringInfoString(&buf,
-							   quote_ident_cstr(NameStr(tupdesc->attrs[pkattnum]->attname)));
+							   quote_ident_cstr(NameStr(attr->attname)));
 
 		if (src_pkattvals[i] != NULL)
 			appendStringInfo(&buf, " = %s",
@@ -2894,7 +2903,7 @@ validate_pkattnums(Relation rel,
 		for (j = 0; j < natts; j++)
 		{
 			/* dropped columns don't count */
-			if (tupdesc->attrs[j]->attisdropped)
+			if (TupleDescAttr(tupdesc, j)->attisdropped)
 				continue;
 
 			if (++lnum == pkattnum)

contrib/file_fdw/file_fdw.c

@@ -430,7 +430,7 @@ get_file_fdw_attribute_options(Oid relid)
 	/* Retrieve FDW options for all user-defined attributes. */
 	for (attnum = 1; attnum <= natts; attnum++)
 	{
-		Form_pg_attribute attr = tupleDesc->attrs[attnum - 1];
+		Form_pg_attribute attr = TupleDescAttr(tupleDesc, attnum - 1);
 		List	   *options;
 		ListCell   *lc;
 
@@ -898,7 +898,7 @@ check_selective_binary_conversion(RelOptInfo *baserel,
 		/* Get user attributes. */
 		if (attnum > 0)
 		{
-			Form_pg_attribute attr = tupleDesc->attrs[attnum - 1];
+			Form_pg_attribute attr = TupleDescAttr(tupleDesc, attnum - 1);
 			char	   *attname = NameStr(attr->attname);
 
 			/* Skip dropped attributes (probably shouldn't see any here). */
@@ -912,7 +912,7 @@ check_selective_binary_conversion(RelOptInfo *baserel,
 	numattrs = 0;
 	for (i = 0; i < tupleDesc->natts; i++)
 	{
-		Form_pg_attribute attr = tupleDesc->attrs[i];
+		Form_pg_attribute attr = TupleDescAttr(tupleDesc, i);
 
 		if (attr->attisdropped)
 			continue;

contrib/hstore/hstore_io.c

@@ -855,15 +855,16 @@ hstore_from_record(PG_FUNCTION_ARGS)
 	for (i = 0, j = 0; i < ncolumns; ++i)
 	{
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+		Oid			column_type = att->atttypid;
 		char	   *value;
 
 		/* Ignore dropped columns in datatype */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 			continue;
 
-		pairs[j].key = NameStr(tupdesc->attrs[i]->attname);
-		pairs[j].keylen = hstoreCheckKeyLen(strlen(NameStr(tupdesc->attrs[i]->attname)));
+		pairs[j].key = NameStr(att->attname);
+		pairs[j].keylen = hstoreCheckKeyLen(strlen(NameStr(att->attname)));
 
 		if (!nulls || nulls[i])
 		{
@@ -1034,21 +1035,22 @@ hstore_populate_record(PG_FUNCTION_ARGS)
 	for (i = 0; i < ncolumns; ++i)
 	{
 		ColumnIOData *column_info = &my_extra->columns[i];
-		Oid			column_type = tupdesc->attrs[i]->atttypid;
+		Form_pg_attribute att = TupleDescAttr(tupdesc, i);
+		Oid			column_type = att->atttypid;
 		char	   *value;
 		int			idx;
 		int			vallen;
 
 		/* Ignore dropped columns in datatype */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (att->attisdropped)
 		{
 			nulls[i] = true;
 			continue;
 		}
 
 		idx = hstoreFindKey(hs, 0,
-							NameStr(tupdesc->attrs[i]->attname),
-							strlen(NameStr(tupdesc->attrs[i]->attname)));
+							NameStr(att->attname),
+							strlen(NameStr(att->attname)));
 
 		/*
 		 * we can't just skip here if the key wasn't found since we might have
@@ -1082,7 +1084,7 @@ hstore_populate_record(PG_FUNCTION_ARGS)
 			 */
 			values[i] = InputFunctionCall(&column_info->proc, NULL,
 										  column_info->typioparam,
-										  tupdesc->attrs[i]->atttypmod);
+										  att->atttypmod);
 			nulls[i] = true;
 		}
 		else
@@ -1094,7 +1096,7 @@ hstore_populate_record(PG_FUNCTION_ARGS)
 
 			values[i] = InputFunctionCall(&column_info->proc, value,
 										  column_info->typioparam,
-										  tupdesc->attrs[i]->atttypmod);
+										  att->atttypmod);
 			nulls[i] = false;
 		}
 	}

contrib/pageinspect/heapfuncs.c

@@ -316,7 +316,7 @@ tuple_data_split_internal(Oid relid, char *tupdata,
 		bool		is_null;
 		bytea	   *attr_data = NULL;
 
-		attr = tupdesc->attrs[i];
+		attr = TupleDescAttr(tupdesc, i);
 		is_null = (t_infomask & HEAP_HASNULL) && att_isnull(i, t_bits);
 
 		/*
@@ -334,7 +334,7 @@ tuple_data_split_internal(Oid relid, char *tupdata,
 
 			if (attr->attlen == -1)
 			{
-				off = att_align_pointer(off, tupdesc->attrs[i]->attalign, -1,
+				off = att_align_pointer(off, attr->attalign, -1,
 										tupdata + off);
 
 				/*
@@ -353,7 +353,7 @@ tuple_data_split_internal(Oid relid, char *tupdata,
 			}
 			else
 			{
-				off = att_align_nominal(off, tupdesc->attrs[i]->attalign);
+				off = att_align_nominal(off, attr->attalign);
 				len = attr->attlen;
 			}
 
@@ -371,7 +371,7 @@ tuple_data_split_internal(Oid relid, char *tupdata,
 				memcpy(VARDATA(attr_data), tupdata + off, len);
 			}
 
-			off = att_addlength_pointer(off, tupdesc->attrs[i]->attlen,
+			off = att_addlength_pointer(off, attr->attlen,
 										tupdata + off);
 		}
 

contrib/pageinspect/rawpage.c

@@ -253,7 +253,7 @@ page_header(PG_FUNCTION_ARGS)
 	lsn = PageGetLSN(page);
 
 	/* pageinspect >= 1.2 uses pg_lsn instead of text for the LSN field. */
-	if (tupdesc->attrs[0]->atttypid == TEXTOID)
+	if (TupleDescAttr(tupdesc, 0)->atttypid == TEXTOID)
 	{
 		char		lsnchar[64];
 

contrib/postgres_fdw/deparse.c

@@ -1115,7 +1115,7 @@ deparseTargetList(StringInfo buf,
 	first = true;
 	for (i = 1; i <= tupdesc->natts; i++)
 	{
-		Form_pg_attribute attr = tupdesc->attrs[i - 1];
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, i - 1);
 
 		/* Ignore dropped attributes. */
 		if (attr->attisdropped)
@@ -1851,15 +1851,15 @@ deparseAnalyzeSql(StringInfo buf, Relation rel, List **retrieved_attrs)
 	for (i = 0; i < tupdesc->natts; i++)
 	{
 		/* Ignore dropped columns. */
-		if (tupdesc->attrs[i]->attisdropped)
+		if (TupleDescAttr(tupdesc, i)->attisdropped)
 			continue;
 
 		if (!first)
 			appendStringInfoString(buf, ", ");
 		first = false;
 
 		/* Use attribute name or column_name option. */
-		colname = NameStr(tupdesc->attrs[i]->attname);
+		colname = NameStr(TupleDescAttr(tupdesc, i)->attname);
 		options = GetForeignColumnOptions(relid, i + 1);
 
 		foreach(lc, options)

contrib/postgres_fdw/postgres_fdw.c

@@ -1575,7 +1575,7 @@ postgresPlanForeignModify(PlannerInfo *root,
 
 		for (attnum = 1; attnum <= tupdesc->natts; attnum++)
 		{
-			Form_pg_attribute attr = tupdesc->attrs[attnum - 1];
+			Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1);
 
 			if (!attr->attisdropped)
 				targetAttrs = lappend_int(targetAttrs, attnum);
@@ -1675,6 +1675,7 @@ postgresBeginForeignModify(ModifyTableState *mtstate,
 	Oid			typefnoid;
 	bool		isvarlena;
 	ListCell   *lc;
+	TupleDesc	tupdesc = RelationGetDescr(rel);
 
 	/*
 	 * Do nothing in EXPLAIN (no ANALYZE) case.  resultRelInfo->ri_FdwState
@@ -1719,7 +1720,7 @@ postgresBeginForeignModify(ModifyTableState *mtstate,
 
 	/* Prepare for input conversion of RETURNING results. */
 	if (fmstate->has_returning)
-		fmstate->attinmeta = TupleDescGetAttInMetadata(RelationGetDescr(rel));
+		fmstate->attinmeta = TupleDescGetAttInMetadata(tupdesc);
 
 	/* Prepare for output conversion of parameters used in prepared stmt. */
 	n_params = list_length(fmstate->target_attrs) + 1;
@@ -1748,7 +1749,7 @@ postgresBeginForeignModify(ModifyTableState *mtstate,
 		foreach(lc, fmstate->target_attrs)
 		{
 			int			attnum = lfirst_int(lc);
-			Form_pg_attribute attr = RelationGetDescr(rel)->attrs[attnum - 1];
+			Form_pg_attribute attr = TupleDescAttr(tupdesc, attnum - 1);
 
 			Assert(!attr->attisdropped);
 
@@ -5090,9 +5091,10 @@ conversion_error_callback(void *arg)
 	{
 		/* error occurred in a scan against a foreign table */
 		TupleDesc	tupdesc = RelationGetDescr(errpos->rel);
+		Form_pg_attribute attr = TupleDescAttr(tupdesc, errpos->cur_attno - 1);
 
 		if (errpos->cur_attno > 0 && errpos->cur_attno <= tupdesc->natts)
-			attname = NameStr(tupdesc->attrs[errpos->cur_attno - 1]->attname);
+			attname = NameStr(attr->attname);
 		else if (errpos->cur_attno == SelfItemPointerAttributeNumber)
 			attname = "ctid";
 		else if (errpos->cur_attno == ObjectIdAttributeNumber)

contrib/spi/timetravel.c

@@ -328,7 +328,7 @@ timetravel(PG_FUNCTION_ARGS)
 		for (i = 1; i <= natts; i++)
 		{
 			ctypes[i - 1] = SPI_gettypeid(tupdesc, i);
-			if (!(tupdesc->attrs[i - 1]->attisdropped)) /* skip dropped columns */
+			if (!(TupleDescAttr(tupdesc, i - 1)->attisdropped)) /* skip dropped columns */
 			{
 				snprintf(sql + strlen(sql), sizeof(sql) - strlen(sql), "%c$%d", separ, i);
 				separ = ',';