This renames wait_for_terminate_and_warn() to
wait_for_terminate_and_check(), and adds a flags parameter, that
controls how much to log: there's one flag that means we log about
abnormal stuff, and another one that controls whether we log about
non-zero exit codes. Finally, there's a shortcut flag value for logging
in both cases, as that's what we usually use.
All callers are accordingly updated. At three occasions duplicate logging
is removed, i.e. where the old function was called but logged in the
caller, too.
First of all, let's return pid_t, which appears to be the correct type
given that we return PIDs, and it#s what fork() uses too.
Most importantly though, flush out our PID cache, so that the call
becomes compatible with our getpid_cached() logic.
We were including gcrypt-util.[ch] by hand in the few places where it
was used. Create a convenience library to avoid compiling the same
files multiple times.
v2:
- use a separate static library instead of mergin into libbasic
gcrypt_util_sources had to be moved because otherwise they appeared twice
in libshared.so halfproducts, causing an error.
-fvisibility=default is added to libbasic, libshared_static so that the symbols
appear properly in the exported symbol list in libshared.
The advantage is that files are not compiled twice. When configured with -Dman=false,
the ninja target list is reduced from 1588 to 1347 targets. The difference in compilation
time is small (<10%). I think this is because of -O0 and ccache and multiple cores, and
in different settings the compilation time could be reduced. The main advantage is that
errors and warnings are not reported twice.
The __get_cpuid() function only calls __cpuid() if __get_cpuid_max()
returns a value that is less than or equal to the leaf value.
In QEMU/KVM, I found that the special hypervisor leaf value (0x40000000U)
is always larger than the value retured by __get_cpuid_max().
Avoid this problem by calling the __cpuid() macro directly once we have
checked the hypervisor bit from leaf 1.
Fixes: d31b0033b7
We make assumptions about the comm name we set via PR_SET_NAME: that it
would reflect the process name, but that's only the case for the main
thread. Moreover, we cache the mmap() region without locking.
Let's hence be safe rather than sorry and support all this only in the
main thread.
It's a relatively small wrapper around safe_fork() now, hence let's move
it over, and make its signature even more alike. Also, set a different
process name for the polkit and askpw agents.
This adds a new safe_fork() wrapper around fork() and makes use of it
everywhere. The new wrapper does a couple of things we previously did
manually and separately in a safer, more correct and automatic way:
1. Optionally resets signal handlers/mask in the child
2. Sets a name on all processes we fork off right after forking off (and
the patch assigns useful names for all processes we fork off now,
following a systematic naming scheme: always enclosed in () – in order
to indicate that these are not proper, exec()ed processes, but only
forked off children, and if the process is long-running with only our
own code, without execve()'ing something else, it gets am "sd-" prefix.)
3. Optionally closes all file descriptors in the child
4. Optionally sets a PR_SET_DEATHSIG to SIGTERM in the child, in a safe
way so that the parent dying before this happens being handled
safely.
5. Optionally reopens the logs
6. Optionally connects stdin/stdout/stderr to /dev/null
7. Debug logs about the forked off processes.
Ultimately, O_CLOEXEC should be off in fd 0, 1, 2, but when we open
/dev/null here it's unlikely to be < 0, and after dupping the fd to 0,
1, 2 we turn off O_CLOEXEC explicitly anyway.
Unless we know that what we are about to open will return 0, 1 or 2 we
should always set O_CLOEXEC in order to be safe to other threads forking
of subprocesses at the wrong moment.
Just a minor tweak, making sure we execute as much as we can of the
funciton, but return the first error instead of the last we encounter.
This is usuelly how we do things when we have functions that continue on
the first error, so let's do it like that here too.
Let's fork off sync() ina process instead of a thread, as a safety
measure. This is beneficial to ensure that the original process can exit
without having to wait for the sync() to finish (note that the kernel
will delay process termination until all threads finished their
syscalls). In case of hanging NFS this increases the chance that PID 1
can safely transition to the "systemd-shutdown" process as the sync() is
initiated early on but definitely not waited for.
Lennart Poettering
Shawn Landden
Zbigniew Jędrzejewski-Szmek
Mike Gilbert
Yu Watanabe
Mike Gilbert
bleep_blop
Susant Sahani
Henrik Grindal Bakken