Re: TODO item pg_hba.conf

Gevik Babakhani wrote:

> > I'm not sure if you realize it, but this should be an extremely small
> > patch. In particular, if you think you need to change the parser then
> > you are already off on the wrong track. The parser doesn't know
> > anything about specific privilege types (as of 8.1 anyway). It'd be
> > worth your while to study how the existing privileges on databases
> > are handled, eg, exactly what places know about the TEMP privilege.
>
> To study the existing privileges is the first thing on my list. Because
> I am new to this, it is sometimes difficult to know what is already
> there, and what is possible or not. Your advice in GOLD. Thank you :)

This is how a GRANT/REVOKE works:

1. the command is parsed by the parser (parser/gram.y)
2. a node is created, type GrantStmt
3. the node is picked up by the traffic cop (tcop/utility.c)
4. It's passed to ExecuteGrantStmt (commands/aclchk.c)
5. It's converted to internal form and passed to ExecGrant_Database

Notice the handling of "WITH GRANT OPTION", and observe that the test is
"reversed" on REVOKE, which seems awfully unintuitive.

It should be easy to make this code understand a new privilege type.

--
Alvaro Herrera http://www.CommandPrompt.com/
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