cosmopolitan/third_party/nsync/README.cosmo

DESCRIPTION

  *NSYNC is a synchronization primitives library.

LICENSE

  Apache 2.0

ORIGIN

  git@github.com:google/nsync
  commit ac5489682760393fe21bd2a8e038b528442412a7
  Author: Mike Burrows <m3b@google.com>
  Date:   Wed Jun 1 16:47:52 2022 -0700

LOCAL CHANGES

  - nsync_malloc_() is implemented as kmalloc()
  - nsync_mu_semaphore uses Cosmopolitan Futexes
  - block pthread cancellations in nsync_mu_lock_slow_
  - support posix thread cancellations in nsync_cv_wait
Implement pthread_atfork() If threads are being used, then fork() will now acquire and release and runtime locks so that fork() may be safely used from threads. This also makes vfork() thread safe, because pthread mutexes will do nothing when the process is a child of vfork(). More torture tests have been written to confirm this all works like a charm. Additionally: - Invent hexpcpy() api - Rename nsync_malloc_() to kmalloc() - Complete posix named semaphore implementation - Make pthread_create() asynchronous signal safe - Add rm, rmdir, and touch to command interpreter builtins - Invent sigisprecious() and modify sigset functions to use it - Add unit tests for posix_spawn() attributes and fix its bugs One unresolved problem is the reclaiming of *NSYNC waiter memory in the forked child processes, within apps which have threads waiting on locks 2022-10-16 19:05:08 +00:00			`DESCRIPTION`

			`*NSYNC is a synchronization primitives library.`

			`LICENSE`

			`Apache 2.0`

			`ORIGIN`

			`git@github.com:google/nsync`
			`commit ac5489682760393fe21bd2a8e038b528442412a7`
			`Author: Mike Burrows <m3b@google.com>`
			`Date: Wed Jun 1 16:47:52 2022 -0700`

			`LOCAL CHANGES`

			`- nsync_malloc_() is implemented as kmalloc()`
			`- nsync_mu_semaphore uses Cosmopolitan Futexes`
Make futexes cancellable by pthreads 2022-11-05 01:19:05 +00:00			`- block pthread cancellations in nsync_mu_lock_slow_`
Improve cancellations, randomness, and time - Exhaustively document cancellation points - Rename SIGCANCEL to SIGTHR just like BSDs - Further improve POSIX thread cancellations - Ensure asynchronous cancellations work correctly - Elevate the quality of getrandom() and getentropy() - Make futexes cancel correctly on OpenBSD 6.x and 7.x - Add reboot.com and shutdown.com to examples directory - Remove underscore prefix from awesome timespec_*() APIs - Create assertions that help verify our cancellation points - Remove bad timespec APIs (cmp generalizes eq/ne/gt/gte/lt/lte) 2022-11-06 02:49:41 +00:00			`- support posix thread cancellations in nsync_cv_wait`