Re: Rationalizing code-sharing among src/bin/ directories

On Wed, Mar 23, 2016 at 12:55 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I'm not terribly happy with the hack I used to get pgbench to be able
> to borrow psql's psqlscan.l lexer. It's a mess for the MSVC build
> scripts, and I have seen it causing two concurrent builds of psqlscan.o
> in parallel builds, which is likely to cause a build failure some of
> the time. Another unresolved issue is that we can't apply FLEX_NO_BACKUP
> testing to both of psql's lexers, because that causes each of those
> make steps to want to write lex.backup in the current directory.
>
> I have a modest proposal for improving this: let's move all the code
> that's currently shared by two or more src/bin/ subdirectories into a
> new directory, say src/feutils, and build it into a ".a" library in
> the same way that src/common/ is handled. This would remove the
> following klugy cross-directory links:
>
> src/bin/pgbench/psqlscan.o -> ../../../src/bin/psql/psqlscan.o
> src/bin/psql/dumputils.c -> ../../../src/bin/pg_dump/dumputils.c
> src/bin/psql/keywords.c -> ../../../src/bin/pg_dump/keywords.c
> src/bin/scripts/dumputils.c -> ../../../src/bin/pg_dump/dumputils.c
> src/bin/scripts/keywords.c -> ../../../src/bin/pg_dump/keywords.c
> src/bin/scripts/mbprint.c -> ../../../src/bin/psql/mbprint.c
> src/bin/scripts/print.c -> ../../../src/bin/psql/print.c
>
> Note: the reason for a new subdirectory, rather than putting this
> stuff into src/common/, is that src/common/ is meant for code that's
> shared between frontend and backend, which this stuff is not. Also,
> many of these files depend on libpq which seems like an inappropriate
> dependency for src/common.
>
> Having said that, I also notice these dependencies:
>
> src/bin/pg_dump/kwlookup.c -> ../../../src/backend/parser/kwlookup.c
> src/bin/psql/kwlookup.c -> ../../../src/backend/parser/kwlookup.c
> src/bin/scripts/kwlookup.c -> ../../../src/backend/parser/kwlookup.c
> src/interfaces/ecpg/preproc/kwlookup.c -> ../../../../src/backend/parser/kwlookup.c
> src/bin/initdb/encnames.c -> ../../../src/backend/utils/mb/encnames.c
> src/interfaces/libpq/encnames.c -> ../../../src/backend/utils/mb/encnames.c
>
> which seem like they'd be better handled by moving those files into
> src/common/.
>
> Thoughts?

No objection.

--
Robert Haas
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