Use wrappers of PG_DETOAST_DATUM_PACKED() more.

This makes almost all core code follow the policy introduced in the
previous commit.  Specific decisions:

- Text search support functions with char* and length arguments, such as
  prsstart and lexize, may receive unaligned strings.  I doubt
  maintainers of non-core text search code will notice.

- Use plain VARDATA() on values detoasted or synthesized earlier in the
  same function.  Use VARDATA_ANY() on varlenas sourced outside the
  function, even if they happen to always have four-byte headers.  As an
  exception, retain the universal practice of using VARDATA() on return
  values of SendFunctionCall().

- Retain PG_GETARG_BYTEA_P() in pageinspect.  (Page images are too large
  for a one-byte header, so this misses no optimization.)  Sites that do
  not call get_page_from_raw() typically need the four-byte alignment.

- For now, do not change btree_gist.  Its use of four-byte headers in
  memory is partly entangled with storage of 4-byte headers inside
  GBT_VARKEY, on disk.

- For now, do not change gtrgm_consistent() or gtrgm_distance().  They
  incorporate the varlena header into a cache, and there are multiple
  credible implementation strategies to consider.

1 files changed, 8 insertions, 8 deletions

diff --git a/contrib/adminpack/adminpack.c b/contrib/adminpack/adminpack.c
index a63ff36f05c..10338f951ff 100644
--- a/contrib/adminpack/adminpack.c
+++ b/contrib/adminpack/adminpack.c
@@ -124,8 +124,8 @@ pg_file_write(PG_FUNCTION_ARGS)
 
 	requireSuperuser();
 
-	filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
-	data = PG_GETARG_TEXT_P(1);
+	filename = convert_and_check_filename(PG_GETARG_TEXT_PP(0), false);
+	data = PG_GETARG_TEXT_PP(1);
 
 	if (!PG_GETARG_BOOL(2))
 	{
@@ -147,8 +147,8 @@ pg_file_write(PG_FUNCTION_ARGS)
 				 errmsg("could not open file \"%s\" for writing: %m",
 						filename)));
 
-	count = fwrite(VARDATA(data), 1, VARSIZE(data) - VARHDRSZ, f);
-	if (count != VARSIZE(data) - VARHDRSZ || FreeFile(f))
+	count = fwrite(VARDATA_ANY(data), 1, VARSIZE_ANY_EXHDR(data), f);
+	if (count != VARSIZE_ANY_EXHDR(data) || FreeFile(f))
 		ereport(ERROR,
 				(errcode_for_file_access(),
 				 errmsg("could not write file \"%s\": %m", filename)));
@@ -170,12 +170,12 @@ pg_file_rename(PG_FUNCTION_ARGS)
 	if (PG_ARGISNULL(0) || PG_ARGISNULL(1))
 		PG_RETURN_NULL();
 
-	fn1 = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
-	fn2 = convert_and_check_filename(PG_GETARG_TEXT_P(1), false);
+	fn1 = convert_and_check_filename(PG_GETARG_TEXT_PP(0), false);
+	fn2 = convert_and_check_filename(PG_GETARG_TEXT_PP(1), false);
 	if (PG_ARGISNULL(2))
 		fn3 = 0;
 	else
-		fn3 = convert_and_check_filename(PG_GETARG_TEXT_P(2), false);
+		fn3 = convert_and_check_filename(PG_GETARG_TEXT_PP(2), false);
 
 	if (access(fn1, W_OK) < 0)
 	{
@@ -254,7 +254,7 @@ pg_file_unlink(PG_FUNCTION_ARGS)
 
 	requireSuperuser();
 
-	filename = convert_and_check_filename(PG_GETARG_TEXT_P(0), false);
+	filename = convert_and_check_filename(PG_GETARG_TEXT_PP(0), false);
 
 	if (access(filename, W_OK) < 0)
 	{