g_log_writer_is_journald() works out whether the process’ stderr or
stdout are redirected to journald. While the default writer function
uses this in conjunction with g_log_writer_journald(), that does not
always have to be the case — other writer functions might want to always
write to the journal, and never write to stderr (for example).
Consequently, automatically open the journal socket in
writer_journald(), rather than is_journald().
https://bugzilla.gnome.org/show_bug.cgi?id=769507
journald is a part of systemd which is Linux-only at this time, so only
compile the journald items on Linux only, and just return FALSE for
g_log_writer_is_journald() and G_LOG_WRITER_UNHANDLED for
g_log_writer_journald() on non-Linux.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
Talk to the journal ourselves using sendmsg() instead of linking
against libsystemd for sd_journal_sendv(). At the same time, we
can also avoid excessive copying.
The motivation for dropping the dependency is that we can
then use structured logging e.g. in a flatpak sandbox where
libsystemd may not be present in the runtime.
The code here is inspired by similar code in libvirt.
Currently the docs for GChecksumType are simpy annotated
with 'Since 2.16' which is when GChecksumType was first
introduced. No mention is made of the fact that the
G_CHECKSUM_SHA512 constant was only added much later
in 2.36.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.gnome.org/show_bug.cgi?id=769027
It turns out that the current approach of parsing g_log_structured
varargs is unworkable, because vprintf is not guaranteed to advance
the passed-in va_list. So, we have to reshuffle the argument list
a bit; I've come up with this approach:
g_log_structured (domain, level,
key-value pairs...
"MESSAGE", format,
printf arguments);
This requires a "MESSAGE" key to always be present, and it requires
the "MESSAGE"-format pair to be last, but it avoids an extra NULL
as marker after the key-value pairs. And it can be parsed with a
single pass over the va_list, without any va_copy.
Since we have G_LOG_USE_STRUCTURED, the separate ...structured()
convenience macros are pretty pointless, and I have dropped them
for now.
Look for a macro G_LOG_USE_STRUCTURED, and if it is defined, use
g_log_structured instead of g_log when defining g_warning and friends.
This avoids the extra complication of going through g_logv _and_
g_log_structured to get a message logged; it also lets us pass
the code-related fields.
We don't do this unconditionally (yet), since some users might
rely on the more fine-grained fatality support in g_logv. It has
also been proven problematic in the past to inject a dependency
on bleeding-edge API via a widely-used macro.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
GCC fails to build because of the trailing arguments, not part of the
format:
../../glib/gmessages.c: In function 'g_log_default_handler':
../../glib/gmessages.c:2385:21: error: too many arguments for format
[-Werror=format-extra-args]
NULL);
^
The documentation for `__attribute__((format(...)))` in GCC
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#Common-Function-Attributes
States that the second index must be 0 for functions that are not
available to be checked, like for vprintf-style functions. In this case
it's also appropriate because of the trailing arguments.
The sd-journal API in systemd, upon which the structured logging API is
modelled, also uses 0 as the second argument for the format attribute.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
It turns out that g_info_structured (format, ...) makes
g_info_structured ("Hey!") not work, since it requires at
least one argument after the format string. So shorten
the argument list to just ...
Replace the underlying write_string() call which is the ultimate result
of calling g_log() with a call to g_log_structured(). This means that
all g_log() calls will pass through the structured log handling code
path, as long as they are not already modified or dropped by the g_log()
code (fatal masks, aborts, etc.).
In the case that the default structured log writer is in use, this will
result in the same format of log output to stdout or stderr, as
previously happened. If a non-default writer is in use, it handles the
message as it sees fit.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
If outputting to a terminal which supports coloured output (rather than,
for example, redirecting to a file). This is only enabled for structured
log messages, where colour output support can be tested. It is not
enabled for non-structured log messages.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
In parallel with g_log(), add a new structured logging API, based around
g_log_structured() and various helper functions which are exposed
publicly to allow programs to build their own logging policies easily,
without having to rewrite a lot of gmessages.c because it’s all
internal.
See the expanded documentation at the top of gmessages.c for some
rationale. See the g_log_structured() documentation for some example
code.
https://bugzilla.gnome.org/show_bug.cgi?id=744456
The macro could be used at initialization time to avoid having an
unitialized dict, especially with g_auto variables.
The macro tries to be a bit more type-safe by making sure that the asv
parameter is actually "GVariant *".
https://bugzilla.gnome.org/show_bug.cgi?id=766370
The macro could be used at initialization time to avoid having an
unitialized builder, especially with g_auto variables.
The macro tries to be a bit more type-safe by making sure that the
variant_type parameter is actually "const GVariantType
*". Unfortunately I have no idea how to make it possible to also pass
a "const gchar *" parameter without warning.
https://bugzilla.gnome.org/show_bug.cgi?id=766370
revents is set in the same function after some lines. This check was
using revents from previous loop. This had the problem of causing two
poll execution for every changes to poll records.
Note that is not possible to move the code after revents is updated
as probably poll_changed is TRUE causing the function to exit.
Adapted from a patch by Frediano Ziglio,
https://bugzilla.gnome.org/show_bug.cgi?id=761102
This reduce the frequency the loop is waked up adding and removing
file descriptors or timeouts.
Considering that to support recursion events are removed from list and
added again this reduce iteration number a lot.
Signed-off-by: Frediano Ziglio <fziglio@redhat.com>
https://bugzilla.gnome.org/show_bug.cgi?id=761102
