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44 Commits

Author SHA1 Message Date
David Gibson
b84cd05098 log: Only check for FALLOC_FL_COLLAPSE_RANGE availability at runtime
log.c has several #ifdefs on FALLOC_FL_COLLAPSE_RANGE that won't attempt
to use it if not defined.  But even if the value is defined at compile
time, it might not be available in the runtime kernel, so we need to check
for errors from a fallocate() call and fall back to other methods.

Simplify this to only need the runtime check by using linux_dep.h to define
FALLOC_FL_COLLAPSE_RANGE if it's not in the kernel headers.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-11-08 08:25:58 +01:00
Stefano Brivio
59fe34ee36 treewide: Suppress clang-tidy warning if we already use O_CLOEXEC
In pcap_init(), we should always open the packet capture file with
O_CLOEXEC, even if we're not running in foreground: O_CLOEXEC means
close-on-exec, not close-on-fork.

In logfile_init() and pidfile_open(), the fact that we pass a third
'mode' argument to open() seems to confuse the android-cloexec-open
checker in LLVM versions from 16 to 19 (at least).

The checker is suggesting to add O_CLOEXEC to 'mode', and not in
'flags', where we already have it.

Add a suppression for clang-tidy and a comment, and avoid repeating
those three times by adding a new helper, output_file_open().

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-10-30 12:37:31 +01:00
Stefano Brivio
744247856d treewide: Silence cert-err33-c clang-tidy warnings for fprintf()
We use fprintf() to print to standard output or standard error
streams. If something gets truncated or there's an output error, we
don't really want to try and report that, and at the same time it's
not abnormal behaviour upon which we should terminate, either.

Just silence the warning with an ugly FPRINTF() variadic macro casting
the fprintf() expressions to void.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-10-30 12:37:31 +01:00
Stefano Brivio
0ea60e5a77 log: Don't prefix log file messages with time and severity if they're continuations
In fecb1b65b1 ("log: Don't prefix message with timestamp on --debug
if it's a continuation"), I fixed this for --debug on standard error,
but not for log files: if messages are continuations, they shouldn't
be prefixed by timestamp and severity.

Otherwise, we'll print stuff like this:

  0.0028: ERROR:   Receive error on guest connection, reset0.0028:  ERROR:   : Bad file descriptor

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-09-06 12:52:21 +02:00
Stefano Brivio
2aea1da143 treewide: Allow additional system calls for i386/i686
I haven't tested i386 for a long time (after playing with some
openSUSE i586 image a couple of years ago). It turns out that a number
of system calls we actually need were denied by the seccomp filter,
and not even basic functionality works.

Add some system calls that glibc started using with the 64-bit time
("t64") transition, see also:

  https://wiki.debian.org/ReleaseGoals/64bit-time

that is: clock_gettime64, timerfd_gettime64, fcntl64, and
recvmmsg_time64.

Add further system calls that are needed regardless of time_t width,
that is, mmap2 (valgrind profile only), _llseek and sigreturn (common
outside x86_64), and socketcall (same as s390x).

I validated this against an almost full run of the test suite, with
just a few selected tests skipped. Fixes needed to run most tests on
i386/i686, and other assorted fixes for tests, are included in
upcoming patches.

Reported-by: Uroš Knupleš <uros@knuples.net>
Analysed-by: Faidon Liambotis <paravoid@debian.org>
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1078981
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-08-21 12:00:43 +02:00
Stefano Brivio
fecb1b65b1 log: Don't prefix message with timestamp on --debug if it's a continuation
If we prefix the second part of messages printed through
logmsg_perror() by the timestamp, on debug, we'll have two timestamps
and a weird separator in the result, such as this beauty:

  0.0013: Failed to clone process with detached namespaces0.0013: : Operation not permitted

Add a parameter to logmsg() and vlogmsg() which indicates a message
continuation. If that's set, don't print the timestamp in vlogmsg().

Link: https://github.com/moby/moby/issues/48257#issuecomment-2282875092
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-08-12 16:21:53 +02:00
David Gibson
a628cb93a7 log: Avoid duplicate calls to logtime()
We use logtime() to get a timestamp for the log in two places:
  - in vlogmsg(), which is used only for debug_print messages
  - in logfile_write() which is only used messages to the log file

These cases are mutually exclusive, so we don't ever print the same message
with different timestamps, but that's not particularly obvious to see.
It's possible future tweaks to logging logic could mean we log to two
different places with different timestamps, which would be confusing.

Refactor to have a single logtime() call in vlogmsg() and use it for all
the places we need it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-08-07 09:16:40 +02:00
David Gibson
2c7558dc43 log: Handle errors from clock_gettime()
clock_gettime() can, theoretically, fail, although it probably won't until
2038 on old 32-bit systems.  Still, it's possible someone could run with
a wildly out of sync clock, or new errors could be added, or it could fail
due to a bug in libc or the kernel.

We don't handle this well.  In the debug_print case in vlogmsg we'll just
ignore the failure, and print a timestamp based on uninitialised garbage.
In logfile_write() we exit early and won't log anything at all, which seems
like a good way to make an already weird situation undebuggable.

Add some helpers to instead handle this by using "<error>" in place of a
timestamp if something goes wrong with clock_gettime().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-08-07 09:16:29 +02:00
David Gibson
b91bae1ded log: Correct formatting of timestamps
logtime_fmt_and_arg() is a rather odd macro, producing both a format
string and an argument, which can only be used in quite specific printf()
like formulations.  It also has a significant bug: it tries to display 4
digits after the decimal point (so down to tenths of milliseconds) using
%04i.  But the field width in printf() is always a *minimum* not maximum
field width, so this will not truncate the given value, but will redisplay
the entire tenth-of-milliseconds difference again after the decimal point.

Replace the macro with an snprintf() like function which will format the
timestamp, and use an explicit % to correct the display.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[sbrivio: Make logtime_fmt() static]
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-08-07 09:16:10 +02:00
Stefano Brivio
ee36266a55 log, passt: Keep printing to stderr when passt is running in foreground
There are two cases where we want to stop printing to stderr: if it's
closed, and if pasta spawned a shell (and --debug wasn't given).

But if passt is running in foreground, we currently stop to report any
message, even error messages, once we're ready, as reported by
Laurent, because we set the log_runtime flag, which we use to indicate
we're ready, regardless of whether we're running in foreground or not.

Turn that flag (back) to log_stderr, and set it only when we really
want to stop printing to stderr.

Reported-by: Laurent Vivier <lvivier@redhat.com>
Fixes: afd9cdc9bb ("log, passt: Always print to stderr before initialisation is complete")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-08-06 15:03:48 +02:00
David Gibson
a5bbefa6fb log: Make logfile_write() private
logfile_write() is not used outside log.c, nor should it be.  It should
only be used externall via the general logging functions.  Make it static
in log.c.  To avoid forward declarations this requires moving a bunch of
functions earlier in the file.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-08-05 15:03:33 +02:00
Stefano Brivio
77c092ee5e log: Fetch log times with CLOCK_MONOTONIC, not CLOCK_REALTIME
We report relative timestamps in logs, so we want to avoid jumps in
the system time.

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>
2024-07-26 13:47:36 +02:00
Stefano Brivio
e5c37ba0f4 log: Initialise timestamp for relative log time also if we use a log file
...not just for debug messages. Otherwise, timestamps in the log file
are consistent but the starting point is not zero.

Do this right away as we enter main(), so that the resulting
timestamps are as closely as possible relative to when we start.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-07-26 13:47:34 +02:00
Stefano Brivio
327d9d482f log, util: Fix sub-second part in relative log time calculation
For some reason, in commit 01efc71ddd ("log, conf: Add support for
logging to file"), I added calculations for relative logging
timestamps using the difference for the seconds part only, not for
accounting for the fractional part.

Fix that by storing the initial timestamp, log_start, as a timespec
struct, and by calculating the difference from the starting time. Do
this in a macro as we need the same format in a few places.

To calculate the difference, turn the existing timespec_diff_ms() to
microseconds, timespec_diff_us(), and rewrite timespec_diff_ms() to
use that.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-07-26 13:43:19 +02:00
Stefano Brivio
1cd773081f log: Drop newlines in the middle of the perror()-like messages
Calling vlogmsg() twice from logmsg_perror() results in this beauty:

  $ ./pasta -i foo
  Invalid interface name foo
  : No such device

because the first part of the message, corresponding to the first
call, doesn't end with a newline, and vlogmsg() adds it.

Given that we can't easily append an argument (error description) to
a variadic list, add a 'newline' parameter to all the functions that
currently add a newline if missing, and disable that on the first call
to vlogmsg() from logmsg_perror(). Not very pretty but I can't think
of any solution that's less messy than this.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-07-25 12:25:31 +02:00
Stefano Brivio
c66f0341d9 log: Don't report syslog failures to stderr after initialisation
If we daemonised, we can't use standard error. If we didn't, it's
rather annoying to have all those messages on standard error anyway,
and kind of pointless too, as the messages we wanted to print were
printed to standard error anyway.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-06-21 15:32:48 +02:00
Stefano Brivio
dba7f0f5ce treewide: Replace strerror() calls
Now that we have logging functions embedding perror() functionality,
we can make _some_ calls more terse by using them. In many places,
the strerror() calls are still more convenient because, for example,
they are used in flow debugging functions, or because the return code
variable of interest is not 'errno'.

While at it, convert a few error messages from a scant perror style
to proper failure descriptions.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-06-21 15:32:44 +02:00
Stefano Brivio
92a22fef93 treewide: Replace perror() calls with calls to logging functions
perror() prints directly to standard error, but in many cases standard
error might be already closed, or we might want to skip logging, based
on configuration. Our logging functions provide all that.

While at it, make errors more descriptive, replacing some of the
existing basic perror-style messages.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-06-21 15:32:43 +02:00
Stefano Brivio
c1140df889 log: Add _perror() logging function variants
In many places, we have direct perror() calls, which completely bypass
logging functions and log files.

They are definitely convenient: offer similar convenience with
_perror() logging variants, so that we can drop those direct perror()
calls.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-06-21 15:32:40 +02:00
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
Stefano Brivio
5d5208b67d treewide: Compilers' name for armv6l and armv7l is "arm"
When I switched from 'uname -m' to 'gcc -dumpmachine' to fetch the
architecture name for, among others, seccomp.sh, I didn't realise
that "armv6l" and "armv7l" are just Linux kernel names -- compilers
just call that "arm".

Fix the "syscalls" annotation we use to define seccomp profiles
accordingly, otherwise pasta will be terminated on sigreturn() on
armv6l and armv7l.

Fixes: 213c397492 ("passt, pasta: Run-time selection of AVX2 build")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-04-11 17:34:04 +02:00
Stefano Brivio
f67238aa86 passt, log: Call __openlog() earlier, log to stderr until we detach
Paul reports that, with commit 15001b39ef ("conf: set the log level
much earlier"), early messages aren't reported to standard error
anymore.

The reason is that, once the log mask is changed from LOG_EARLY, we
don't force logging to stderr, and this mechanism was abused to have
early errors on stderr. Now that we drop LOG_EARLY earlier on, this
doesn't work anymore.

Call __openlog() as soon as we know the mode we're running as, using
LOG_PERROR. Then, once we detach, if we're not running from an
interactive terminal and logging to standard error is not forced,
drop LOG_PERROR from the options.

While at it, check if the standard error descriptor refers to a
terminal, instead of checking standard output: if the user redirects
standard output to /dev/null, they might still want to see messages
from standard error.

Further, make sure we don't print messages to standard error reporting
that we couldn't log to the system logger, if we didn't open a
connection yet. That's expected.

Reported-by: Paul Holzinger <pholzing@redhat.com>
Fixes: 15001b39ef ("conf: set the log level much earlier")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-03-14 08:19:36 +01:00
Stefano Brivio
7ee4e17267 log: setlogmask(0) can actually result in a system call, don't use it
Before commit 32d07f5e59 ("passt, pasta: Completely avoid dynamic
memory allocation"), we didn't store the current log mask in a
variable, and we fetched it using setlogmask(0) wherever needed.

But after that commit, we can use our log_mask copy instead. And we
should: with recent glibc versions, setlogmask(0) actually results in
a system call, which causes a substantial overhead with high transfer
rates: we use setlogmask(0) even to decide we don't want to print
debug messages.

Now that we rely on log_mask in early stages, before setlogmask() is
called, we need to initialise that variable to the special LOG_EMERG
mask value right away: define LOG_EARLY to make this clearer, and,
while at it, group conditions in vlogmsg() into something more terse.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2024-02-14 01:10:11 +01:00
David Gibson
8563e7c870 treewide: Standardise on 'now' for current timestamp variables
In a number of places we pass around a struct timespec representing the
(more or less) current time.  Sometimes we call it 'now', and sometimes we
call it 'ts'.  Standardise on the more informative 'now'.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-01-22 23:35:10 +01:00
David Gibson
a179ca6707 treewide: Make a bunch of pointer variables pointers to const
Sufficiently recent cppcheck (I'm using 2.13.0) seems to have added another
warning for pointer variables which could be pointer to const but aren't.
Use this to make a bunch of variables const pointers where they previously
weren't for no particular reason.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2024-01-16 21:49:27 +01:00
Stefano Brivio
50bc25a23c log: Match implicit va_start() with va_end() in vlogmsg()
According to C99, 7.15.1:

  Each invocation of the va_start and va_copy macros shall be matched
  by a corresponding invocation of the va_end macro in the same
  function

and the same applies to C11. I still have to come across a platform
where va_end() actually does something, but thus spake the standard.
This would be reported by Coverity as "Missing varargs init or
cleanup" (CWE-573).

Fixes: c0426ff10b ("log: Add vlogmsg()")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-11-07 12:24:27 +01:00
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
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
David Gibson
6471c7d01b cppcheck: Make many pointers const
Newer versions of cppcheck (as of 2.12.0, at least) added a warning for
pointers which could be declared to point at const data, but aren't.
Based on that, make many pointers throughout the codebase const.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-10-04 23:23:35 +02:00
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
4e6178fd46 log: Avoid time_t/__syscall_slong_t format mismatch with long int on X32 ABI
On X32 (ILP32 using AMD64 system call ABI) and glibc,
struct timespec::tv_nsec is __syscall_slong_t and not a long int, see
also https://sourceware.org/bugzilla/show_bug.cgi?id=16437 and
timespec(3type). Fine, we could cast that down to long and be done
with it.

But it turns out that also time_t (not guaranteed to be equivalent to
any type) is a long long int, and there we can't downcast.

To keep it simple, cast both to long long int, and change formats to
%lli, to avoid format warnings from gcc.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-03-17 08:25:56 +01:00
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
Stefano Brivio
834b9a3049 log: Send identifier string in log messages, openlog() won't work for us
openlog() can be used to set "ident" and have all the log messages
prefixed by it, but only if we call syslog() -- this is implemented
by C libraries.

We don't log messages with syslog(), though, as we have a custom
implementation to ensure we don't need dynamic memory allocation.
This means that it's perfectly useless to call openlog(), and that we
have to prefix every message we log by the identifier on our own.

Reported-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Tested-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-02-27 18:53:38 +01:00
Stefano Brivio
b4f13c2b18 log: Don't duplicate messages on stderr before daemonising
Now that logging functions force printing messages to stderr before
passt forks to background, we'll have duplicate messages when running
from an interactive terminal, or if --stderr is passed, because at
some point we set LOG_PERROR in our __openlog() wrapper.

We could defer setting LOG_PERROR, but that would change option
semantics in other, unexpected ways. We could force calling
passt_vsyslog() as long as the mask is set to LOG_EMERG, but that
complicates the logic in logging functions even further.

Go the easy way for now: don't force printing to stderr with
LOG_EMERG if LOG_PERROR is already set. We should seriously consider a
rework of those logging functions at this point.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2023-02-16 17:32:30 +01:00
Laine Stump
c9af6f92db convert all remaining err() followed by exit() to die()
This actually leaves us with 0 uses of err(), but someone could want
to use it in the future, so we may as well leave it around.

Signed-off-by: Laine Stump <laine@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-02-16 17:32:27 +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
Laine Stump
193385bd2f log to stderr until process is daemonized, even if a log file is set
Once a log file (specified on the commandline) is opened, the logging
functions will stop sending error logs to stderr, which is annoying if
passt has been started by another process that wants to collect error
messages from stderr so it can report why passt failed to start. It
would be much nicer if passt continued sending all log messages to
stderr until it daemonizes itself (at which point the process that
started passt can assume that it was started successfully).

The system log mask is set to LOG_EMERG when the process starts, and
we're already using that to do "special" logging during the period
from process start until the log level requested on the commandline is
processed (setting the log mask to something else). This period
*almost* matches with "the time before the process is daemonized"; if
we just delay setting the log mask a tiny bit, then it will match
exactly, and we can use it to determine if we need to send log
messages to stderr even when a log file has been specified and opened.

This patch delays the setting of the log mask until immediately before
the call to __daemon(). It also modifies logfn() slightly, so that it
will log to stderr any time log mask is LOG_EMERG, even if a log file
has been opened.

Signed-off-by: Laine Stump <laine@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2023-02-16 17:31:42 +01:00
Stefano Brivio
e23024ccff conf, log, Makefile: Add versioning information
Add a --version option displaying that, and also include this
information in the log files.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-15 02:10:28 +02:00
Stefano Brivio
2074b332f9 log: Add missing function comment for trace_init()
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2022-10-14 17:38:58 +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