Re: [HACKERS] Patch for user-defined C-language functions

Bernard Frankpitt <frankpit(at)pop(dot)dn(dot)net> writes:
> The solution that I propose, and have implemented in the attatched
> patch extends the CREATE FUNCTION syntax as follows. In the first case
> above I use the link symbol mytype2_to_mytype3 for the link object
> that implements the first conversion function, and define the
> Postgresql operator with the following syntax
> CREATE FUNCTION mytype3 ( mytype2 )
> RETURNS mytype3
> AS 'mytypes.so', 'mytype2_to_mytype3'
> LANGUAGE 'C'
> The syntax for the AS clause, which was 'AS <link-file>' becomes
> AS <link_file>[, <link_name>]
> Specification of the link_name is optional, and not needed if the link
> name is the same as the Postgresql function name.

> I store the string for the link symbol in the prosrc text attribute of
> the pg_proc table which is currently unused in rows that reference
> dynamically loaded functions.

Sounds like a good plan to me. I'll be glad to check this over and
commit it into 6.6 (unless there are objections?) ... but could I
trouble you for documentation diffs as well? At the very least,
the text discussion of CREATE FUNCTION, the reference page entry,
and the online help in psql need to reflect this addition.

regards, tom lane