Simplify and standardize conversions between TEXT datums and ordinary C

strings.  This patch introduces four support functions cstring_to_text,
cstring_to_text_with_len, text_to_cstring, and text_to_cstring_buffer, and
two macros CStringGetTextDatum and TextDatumGetCString.  A number of
existing macros that provided variants on these themes were removed.

Most of the places that need to make such conversions now require just one
function or macro call, in place of the multiple notational layers that used
to be needed.  There are no longer any direct calls of textout or textin,
and we got most of the places that were using handmade conversions via
memcpy (there may be a few still lurking, though).

This commit doesn't make any serious effort to eliminate transient memory
leaks caused by detoasting toasted text objects before they reach
text_to_cstring.  We changed PG_GETARG_TEXT_P to PG_GETARG_TEXT_PP in a few
places where it was easy, but much more could be done.

Brendan Jurd and Tom Lane

1 files changed, 5 insertions, 4 deletions

diff --git a/src/backend/utils/init/flatfiles.c b/src/backend/utils/init/flatfiles.c
index aa155a07bb3..cffbc51bbdc 100644
--- a/src/backend/utils/init/flatfiles.c
+++ b/src/backend/utils/init/flatfiles.c
@@ -23,7 +23,7 @@
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/backend/utils/init/flatfiles.c,v 1.30 2008/01/01 19:45:53 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/init/flatfiles.c,v 1.31 2008/03/25 22:42:45 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -461,13 +461,14 @@ write_auth_file(Relation rel_authid, Relation rel_authmem)
 			 * it is, ignore it, since we can't handle that in startup mode.
 			 *
 			 * It is entirely likely that it's 1-byte format not 4-byte, and
-			 * theoretically possible that it's compressed inline, but textout
-			 * should be able to handle those cases even in startup mode.
+			 * theoretically possible that it's compressed inline, but
+			 * text_to_cstring should be able to handle those cases even in
+			 * startup mode.
 			 */
 			if (VARATT_IS_EXTERNAL(DatumGetPointer(datum)))
 				auth_info[curr_role].rolpassword = pstrdup("");
 			else
-				auth_info[curr_role].rolpassword = DatumGetCString(DirectFunctionCall1(textout, datum));
+				auth_info[curr_role].rolpassword = TextDatumGetCString(datum);
 
 			/* assume passwd has attlen -1 */
 			off = att_addlength_pointer(off, -1, tp + off);