Обсуждение: local_preload_libraries filenames converted to lowercase

Severity: minor

Tested On:  9.0b2, 8.4.4

Platform: SUN SPARC 4u Enterprise 450 Quad, presumably Solaris 10

Repeatable?  Yes

Description:

   See thread:
   http://archives.postgresql.org/pgsql-testers/2010-06/msg00020.php

--
                                  -- Josh Berkus
                                     PostgreSQL Experts Inc.
                                     http://www.pgexperts.com

Josh Berkus <josh@agliodbs.com> writes:
>    http://archives.postgresql.org/pgsql-testers/2010-06/msg00020.php

We'd need to see exactly how local_preload_libraries is being set.

            regards, tom lane

Josh Berkus <josh@agliodbs.com> writes:
>    http://archives.postgresql.org/pgsql-testers/2010-06/msg00020.php

OK, I looked at this a bit, and the answer is that load_libraries uses
SplitIdentifierString, ie, it thinks the value of the variable is a list
of comma-separated SQL identifiers.  So if you want a
filename containing upper case, whitespace, or commas, double-quote it.

That might seem a bit bizarre, but because of the special meaning of
commas we'd need some quoting rule anyhow.  I'm not sure it's worth
making local_preload_libraries have its own private parsing convention.
Perhaps this is just a documentation deficiency.

            regards, tom lane

> That might seem a bit bizarre, but because of the special meaning of
> commas we'd need some quoting rule anyhow.  I'm not sure it's worth
> making local_preload_libraries have its own private parsing convention.
> Perhaps this is just a documentation deficiency.

Yes, I'd say that documentation is the answer, given.  Hmmm .... are
double-quotes respected in postgresql.conf, though?  Need testing.


--
                                  -- Josh Berkus
                                     PostgreSQL Experts Inc.
                                     http://www.pgexperts.com

Josh Berkus <josh@agliodbs.com> writes:
> Yes, I'd say that documentation is the answer, given.  Hmmm .... are
> double-quotes respected in postgresql.conf, though?  Need testing.

Not sure.  Something like

    local_preload_libraries = '"Foo", "Bar"'

will definitely work.  Don't know if you can dispense with the outer
single quotes.

            regards, tom lane

Tom Lane wrote:
> Josh Berkus <josh@agliodbs.com> writes:
> > Yes, I'd say that documentation is the answer, given.  Hmmm .... are
> > double-quotes respected in postgresql.conf, though?  Need testing.
>
> Not sure.  Something like
>
>     local_preload_libraries = '"Foo", "Bar"'
>
> will definitely work.  Don't know if you can dispense with the outer
> single quotes.

I have documented the requirement for double quotes; attached patch
applied.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + None of us is going to be here forever. +
Index: doc/src/sgml/config.sgml
===================================================================
RCS file: /cvsroot/pgsql/doc/src/sgml/config.sgml,v
retrieving revision 1.285
diff -c -c -r1.285 config.sgml
*** doc/src/sgml/config.sgml    28 Jun 2010 22:46:11 -0000    1.285
--- doc/src/sgml/config.sgml    29 Jun 2010 22:17:58 -0000
***************
*** 1015,1020 ****
--- 1015,1021 ----
          <literal>mylib.so</> (or on some platforms,
          <literal>mylib.sl</>) to be preloaded from the installation's
          standard library directory.
+         All library names are converted to lowercase unless double-quoted.
          If more than one library is to be loaded, separate their names
          with commas.  This parameter can only be set at server start.
         </para>
***************
*** 4838,4844 ****
         <para>
          This variable specifies one or more shared libraries that are
          to be preloaded at connection start.  If more than one library
!         is to be loaded, separate their names with commas.
          This parameter cannot be changed after the start of a particular
          session.
         </para>
--- 4839,4846 ----
         <para>
          This variable specifies one or more shared libraries that are
          to be preloaded at connection start.  If more than one library
!         is to be loaded, separate their names with commas.  All library
!         names are converted to lowercase unless double-quoted.
          This parameter cannot be changed after the start of a particular
          session.
         </para>