Re: pg_regress: lookup shellprog in $PATH - Mailing list pgsql-hackers

From Noah Misch
Subject Re: pg_regress: lookup shellprog in $PATH
Date
Msg-id 20221001195955.GA94708@gust.leadboat.com
Whole thread Raw
In response to Re: pg_regress: lookup shellprog in $PATH  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On Thu, Aug 25, 2022 at 04:04:39PM -0400, Tom Lane wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
> > On Thu, Aug 25, 2022 at 10:48 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> If we were executing a program that the user needs to have some control
> >> over, sure, but what we have here is an implementation detail that I
> >> doubt anyone cares about.  The fact that we're using a shell at all is
> >> only because nobody has cared to manually implement I/O redirection logic
> >> in these places; otherwise we'd be execl()'ing the server or psql directly.
> >> Maybe the best answer would be to do that, and get out of the business
> >> of knowing where the shell is?

> The Windows side of this is completely untested and may be broken; also,
> perhaps Windows has something more nearly equivalent to execvp() that we
> could use instead of reconstructing a command line?  It's annoying that

Windows has nothing like execvp(), unfortunately.

> the patch removes all shell-quoting hazards on the Unix side but they
> are still there on the Windows side.

It's feasible to take cmd.exe out of the loop.  One could then eliminate
cmd.exe quoting (the "^" characters).  Can't avoid the rest of the quoting
(https://docs.microsoft.com/en-us/cpp/cpp/main-function-command-line-args#parsing-c-command-line-arguments).
Bypassing cmd.exe would also make it easy to remove the ban on newlines and
carriage returns in arguments.



pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: Question: test "aggregates" failed in 32-bit machine
Next
From: Andres Freund
Date:
Subject: Re: interrupted tap tests leave postgres instances around