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, 7 insertions, 7 deletions

diff --git a/contrib/xml2/xslt_proc.c b/contrib/xml2/xslt_proc.c
index 343924e9917..391e6b593b0 100644
--- a/contrib/xml2/xslt_proc.c
+++ b/contrib/xml2/xslt_proc.c
@@ -49,8 +49,8 @@ xslt_process(PG_FUNCTION_ARGS)
 {
 #ifdef USE_LIBXSLT
 
-	text	   *doct = PG_GETARG_TEXT_P(0);
-	text	   *ssheet = PG_GETARG_TEXT_P(1);
+	text	   *doct = PG_GETARG_TEXT_PP(0);
+	text	   *ssheet = PG_GETARG_TEXT_PP(1);
 	text	   *result;
 	text	   *paramstr;
 	const char **params;
@@ -66,7 +66,7 @@ xslt_process(PG_FUNCTION_ARGS)
 
 	if (fcinfo->nargs == 3)
 	{
-		paramstr = PG_GETARG_TEXT_P(2);
+		paramstr = PG_GETARG_TEXT_PP(2);
 		params = parse_params(paramstr);
 	}
 	else
@@ -85,16 +85,16 @@ xslt_process(PG_FUNCTION_ARGS)
 		bool		xslt_sec_prefs_error;
 
 		/* Parse document */
-		doctree = xmlParseMemory((char *) VARDATA(doct),
-								 VARSIZE(doct) - VARHDRSZ);
+		doctree = xmlParseMemory((char *) VARDATA_ANY(doct),
+								 VARSIZE_ANY_EXHDR(doct));
 
 		if (doctree == NULL)
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_EXTERNAL_ROUTINE_EXCEPTION,
 						"error parsing XML document");
 
 		/* Same for stylesheet */
-		ssdoc = xmlParseMemory((char *) VARDATA(ssheet),
-							   VARSIZE(ssheet) - VARHDRSZ);
+		ssdoc = xmlParseMemory((char *) VARDATA_ANY(ssheet),
+							   VARSIZE_ANY_EXHDR(ssheet));
 
 		if (ssdoc == NULL)
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_EXTERNAL_ROUTINE_EXCEPTION,