[Swan-dev] lsw_abort => passert
andrew.cagney at gmail.com
Mon Mar 20 14:20:39 UTC 2017
[I see my e-mail went out, I got a weird bounce]
On 19 March 2017 at 22:47, D. Hugh Redelmeier <hugh at mimosa.com> wrote:
> | From: Andrew Cagney <andrew.cagney at gmail.com>
> | > Did you check that the very early calls to lsw_abort can safely be
> | > replaced by passerts? These are the ones in plutomain.c. (I have
> | > not.) Logging may not be initialized.
> What I meant: they were JUST calls to abort. In FreeS/WAN.
That's really going back. Here's the relevant change:
Date: Wed Nov 26 15:14:38 2008 +1000
Convert pluto over to it's own more verbose abort code. Makes find
application aborts a little easier on embedded systems.
> | Only in the sense that I ran the testsuite.
> That will never cause those asserts to fire:
> passert(open("/dev/null", O_RDONLY) == 0);
> passert(dup2(0, 1) == 1);
> passert(log_to_stderr || dup2(0, 2) == 2);
> Those only fire when something is seriously wrong with the environment.
Think of it as a challenge :-)
> | final_breath = TRUE;
> passert is modelled on assert(3). It could be a macro that does
> nothing (not even evaluating its argument). So depending on a
> side-effect of argument evaluation is a no-no.
passert() was once modelled on assert(3); fortunately the code base
has since moved beyond that :-)
Date: Sun Dec 15 20:27:17 2013 -0500
building: Remove #ifdef DEBUG - always compile into userland
This already did not affect KLIPS (although some KLIPS code did use
Note the NSS PR_ASSERT() function depends on DEBUG being set, so we
now define DEBUG 1 in libreswan.h.
so what looks like a function call now behaves like a function call -
its parameter is always evaluated once.
> I'd say that the original FreeS/WAN code is better than all its
> if (open("/dev/null", O_RDONLY) != 0)
> if (dup2(0, 1) != 1)
> if (!log_to_stderr && dup2(0, 2) != 2)
> Since these cannot fail in a normal environment, it is good to not
> depend on much of the environment when failure is detected (passert
> does, lsw_abort does, abort does not).
It's a trade off. I'd prefer the code to at least try to print
something (before the embedded board locks up hard and allows the
magic blue smoke to escape :-), I suspect that was part of the
motivation behind the original change.
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