As a follow up to Ibba98f5d88be1c306d14e9b9366302ecbef6d534, where we
added a work around to convert the CLOCK_REALTIME timeouts to
CLOCK_MONOTONIC for pthread and semaphore timed wait functions, we're
introducing a set of _monotonic_np versions of each of these functions
that wait on CLOCK_MONOTONIC directly.
The primary motivation here is that while the above work around helps
for 3rd party code, it creates a dilemma when implementing new code
that would use these functions: either one implements code with these
functions knowing there is a race condition possible or one avoids
these functions and reinvent their own waiting/signaling mechanisms.
Neither are satisfactory, so we create a third option to use these
Android specific _monotonic_np functions that completely remove the
race condition while keeping the rest of the interface.
Specifically this adds the below functions:
pthread_mutex_timedlock_monotonic_np()
pthread_cond_timedwait_monotonic_np()
pthread_rwlock_timedrdlock_monotonic_np()
pthread_rwlock_timedwrlock_monotonic_np()
sem_timedwait_monotonic_np()
Note that pthread_cond_timedwait_monotonic_np() previously existed and
was removed since it's possible to initialize a condition variable to
use CLOCK_MONOTONIC. It is added back for a mix of reasons,
1) Symmetry with the rest of the functions we're adding
2) libc++ cannot easily take advantage of the new initializer, but
will be able to use this function in order to wait on
std::steady_clock
3) Frankly, it's a better API to specify the clock in the waiter function
than to specify the clock when the condition variable is
initialized.
Bug: 73951740
Test: new unit tests
Change-Id: I23aa5c204e36a194237d41e064c5c8ccaa4204e3
We saw crashes from pthread_exit+debuggerd on LP32
(https://issuetracker.google.com/72291624), and it seems like the
equivalent problem should exist with system(3). I fixed posix_spawn(3)
as part of that bug, so the easiest fix is probably to reuse that.
Bug: http://b/72470344
Test: ran tests
Change-Id: I05f838706f2b4a14ac3ee21292833e6c8579b0d4
Broke the build. There's no such file as bionic_sdk_version.h anywhere in the tree.
This reverts commit 892b61d340.
Change-Id: Iec3f4588edfb1d1524bb5f16451fd05dc6ebe44a
Posix standards says sem_wait is interruptible by the delivery
of a signal. To keep compatiblity with old apps, only fix that
in newer sdk versions.
Bug: 26743454
Change-Id: I924cbb436658e3e0f397c922d866ece99b8241a3
It actually means "crash immediately". Well, it's an error. And callers are
much more likely to realize their mistake if we crash immediately rather
than return EINVAL. Historically, glibc has crashed and bionic -- before
the recent changes -- returned EINVAL, so this is a behavior change.
Change-Id: I0c2373a6703b20b8a97aacc1e66368a5885e8c51