Commit graph

13 commits

Author SHA1 Message Date
Stefano Brivio
afd9cdc9bb log, passt: Always print to stderr before initialisation is complete
After commit 15001b39ef ("conf: set the log level much earlier"), we
had a phase during initialisation when messages wouldn't be printed to
standard error anymore.

Commit f67238aa86 ("passt, log: Call __openlog() earlier, log to
stderr until we detach") fixed that, but only for the case where no
log files are given.

If a log file is configured, vlogmsg() will not call passt_vsyslog(),
but during initialisation, LOG_PERROR is set, so to avoid duplicated
prints (which would result from passt_vsyslog() printing to stderr),
we don't call fprintf() from vlogmsg() either.

This is getting a bit too complicated. Instead of abusing LOG_PERROR,
define an internal logging flag that clearly represents that we're not
done with the initialisation phase yet.

If this flag is not set, make sure we always print to stderr, if the
log mask matches.

Reported-by: Yalan Zhang <yalzhang@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-06-21 15:32:34 +02:00
Stefano Brivio
8c2f24a560 conf, log: Instead of abusing log levels, add log_conf_parsed flag
We currently use a LOG_EMERG log mask to represent the fact that we
don't know yet what the mask resulting from configuration should be,
before the command line is parsed.

However, we have the necessity of representing another phase as well,
that is, configuration is parsed but we didn't daemonise yet, or
we're not ready for operation yet. The next patch will add that
notion explicitly.

Mapping these cases to further log levels isn't really practical.
Introduce boolean log flags to represent them, instead of abusing
log priorities.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-06-21 15:32:31 +02:00
David Gibson
b3aeb004ea log: Remove log_to_stdout option
Now that we've simplified how usage() works, nothing ever sets the
log_to_stdout flag. Eliminate it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-06-05 21:14:09 +02:00
David Gibson
c0426ff10b log: Add vlogmsg()
Currently logmsg() is only available as a variadic function.  This is fine
for normal use, but is awkward if we ever want to write wrappers around it
which (for example) add standardised prefix information.  To allow that,
add a vlogmsg() function which takes a va_list instead, and implement
logmsg() in terms of it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-11-07 09:54:59 +01:00
David Gibson
5972203174 log: Enable format warnings
logmsg() takes printf like arguments, but because it's not a built in, the
compiler won't generate warnings if the format string and parameters don't
match.  Enable those by using the format attribute.

Strictly speaking this is a gcc extension, but I believe it is also
supported by some other common compilers.  We already use some other
attributes in various places.  For now, just use it and we can worry about
compilers that don't support it if it comes up.

This exposes some warnings from existing callers, both in gcc and in
clang-tidy:
 - Some are straight out bugs, which we correct
 - It's occasionally useful to invoke the logging functions with an empty
   string, which gcc objects to, so disable that specific warning in the
   Makefile
 - Strictly speaking the C standard requires that the parameter for a %p
   be a (void *), not some other pointer type.  That's only likely to cause
   problems in practice on weird architectures with different sized
   representations for pointers to different types.  Nonetheless add the
   casts to make it happy.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-11-07 09:54:56 +01:00
David Gibson
50d46ec847 log: Don't define logging function 4 times
In log.c we use a macro to define logging functions for each of 4 priority
levels.  The only difference between these is the priority we pass to
vsyslog() and similar functions.  Because it's done as a macro, however,
the entire functions code is included in the binary 4 times.

Rearrange this to take the priority level as a parameter to a regular
function, then just use macros to define trivial wrappers which pass the
priority level.

This saves about 600 bytes of text in the executable (x86, non-AVX2).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-11-07 09:54:53 +01:00
Stefano Brivio
3c6d1b9bb2 conf, log: On -h / --help, print usage to stdout, not stderr
Erik suggests that this makes it easier to grep for options, and with
--help we're anyway printing usage information as expected, not as
part of an error report.

While at it: on -h, we should exit with 0.

Reported-by: Erik Sjölund <erik.sjolund@gmail.com>
Link: https://bugs.passt.top/show_bug.cgi?id=52
Link: https://bugs.passt.top/show_bug.cgi?id=53
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-06-23 10:15:55 +02:00
Stefano Brivio
ca2749e1bd passt: Relicense to GPL 2.0, or any later version
In practical terms, passt doesn't benefit from the additional
protection offered by the AGPL over the GPL, because it's not
suitable to be executed over a computer network.

Further, restricting the distribution under the version 3 of the GPL
wouldn't provide any practical advantage either, as long as the passt
codebase is concerned, and might cause unnecessary compatibility
dilemmas.

Change licensing terms to the GNU General Public License Version 2,
or any later version, with written permission from all current and
past contributors, namely: myself, David Gibson, Laine Stump, Andrea
Bolognani, Paul Holzinger, Richard W.M. Jones, Chris Kuhn, Florian
Weimer, Giuseppe Scrivano, Stefan Hajnoczi, and Vasiliy Ulyanov.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-04-06 18:00:33 +02:00
Stefano Brivio
d2df763232 log, conf, tap: Define die() as err() plus exit(), drop cppcheck workarounds
If we define die() as a variadic macro, passing __VA_ARGS__ to err(),
and calling exit() outside err() itself, we can drop the workarounds
introduced in commit 36f0199f6e ("conf, tap: Silence two false
positive invalidFunctionArg from cppcheck").

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-02-27 18:55:57 +01:00
Laine Stump
dac4af81e3 add die() to log an error message and exit with a single call
Almost all occurences of err() are either immediately followed by
exit(EXIT_FAILURE), usage(argv[0]) (which itself then calls
exit(EXIT_FAILURE), or that is what's done immediately after returning
from the function that calls err(). Modify the errfn macro so that its
instantiations can include exit(EXIT_FAILURE) at the end, and use that
to create a new function die() that will log an error and then
exit.

Signed-off-by: Laine Stump <laine@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-02-16 17:32:03 +01:00
Stefano Brivio
7f2a7396e2 log.h: Avoid unnecessary GNU extension for token pasting
clang says:

  ./log.h:23:18: warning: token pasting of ',' and __VA_ARGS__ is a GNU extension [-Wgnu-zero-variadic-macro-arguments]

We need token pasting here just because of the 'format' in trace():
drop it.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:36 +02:00
Stefano Brivio
01efc71ddd log, conf: Add support for logging to file
In some environments, such as KubeVirt pods, we might not have a
system logger available. We could choose to run in foreground, but
this takes away the convenient synchronisation mechanism derived from
forking to background when interfaces are ready.

Add optional logging to file with -l/--log-file and --log-size.

Unfortunately, this means we need to duplicate features that are more
appropriately implemented by a system logger, such as rotation. Keep
that reasonably simple, by using fallocate() with range collapsing
where supported (Linux kernel >= 3.15, extent-based ext4 and XFS) and
falling back to an unsophisticated block-by-block moving of entries
toward the beginning of the file once we reach the (mandatory) size
limit.

While at it, clarify the role of LOG_EMERG in passt.c.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:28 +02:00
Stefano Brivio
da152331cf Move logging functions to a new file, log.c
Logging to file is going to add some further complexity that we don't
want to squeeze into util.c.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:25 +02:00