Fix unsafe coding around PG_TRY in RelationBuildRowSecurity: can't change
a variable inside PG_TRY and then use it in PG_CATCH without marking it
"volatile". In this case though it seems saner to avoid that by doing
a single assignment before entering the TRY block.
I started out just intending to fix that, but the more I looked at the
row-security code the more distressed I got. This patch also fixes
incorrect construction of the RowSecurityPolicy cache entries (there was
not sufficient care taken to copy pass-by-ref data into the cache memory
context) and a whole bunch of sloppiness around the definition and use of
pg_policy.polcmd. You can't use nulls in that column because initdb will
mark it NOT NULL --- and I see no particular reason why a null entry would
be a good idea anyway, so changing initdb's behavior is not the right
answer. The internal value of '\0' wouldn't be suitable in a "char" column
either, so after a bit of thought I settled on using '*' to represent ALL.
Chasing those changes down also revealed that somebody wasn't paying
attention to what the underlying values of ACL_UPDATE_CHR etc really were,
and there was a great deal of lackadaiscalness in the catalogs.sgml
documentation for pg_policy and pg_policies too.
This doesn't pretend to be a complete code review for the row-security
stuff, it just fixes the things that were in my face while dealing with
the bugs in RelationBuildRowSecurity.
@ -2851,9 +2851,9 @@ getPolicies(Archive *fout, TableInfo tblinfo[], int numTables)
appendPQExpBuffer(query,
"SELECT oid, tableoid, pol.polname, pol.polcmd, "
"CASE WHEN pol.polroles = '{0}' THEN 'PUBLIC' ELSE "
" array_to_string(ARRAY(SELECT rolname from pg_roles WHERE oid = ANY(pol.polroles)), ', ') END AS polroles, "
"pg_get_expr(pol.polqual, pol.polrelid) AS polqual, "
"pg_get_expr(pol.polwithcheck, pol.polrelid) AS polwithcheck "
"pg_catalog.array_to_string(ARRAY(SELECT pg_catalog.quote_ident(rolname) from pg_catalog.pg_roles WHERE oid = ANY(pol.polroles)), ', ') END AS polroles, "
"pg_catalog.pg_get_expr(pol.polqual, pol.polrelid) AS polqual, "
"pg_catalog.pg_get_expr(pol.polwithcheck, pol.polrelid) AS polwithcheck "
"FROM pg_catalog.pg_policy pol "
"WHERE polrelid = '%u'",
tbinfo->dobj.catId.oid);
@ -2865,7 +2865,7 @@ getPolicies(Archive *fout, TableInfo tblinfo[], int numTables)