Summary: `waitOrTerminateOrKill` fills the gap between `wait()` and `terminateOrKill`. It allows giving the subprocess a chance to shut down cleanly (after closing its stdin pipe, for example), but avoids waiting forever or leaking a child process.

Reviewed By: yfeldblum, mzhaom

Differential Revision: D17769090

fbshipit-source-id: 8940fd63f7eb9c09ef293c89a5e97f69805735ff

Summary:
QuotientMultiSet is a space-efficient static data structure to store a non-decreasing sequence of b-bit integers.

If the integers are uniformly distributed lookup is O(1)-time and performs a single random memory lookup with high probability.

Reviewed By: ot

Differential Revision: D17506766

fbshipit-source-id: b3e7a22dd193672fadb07d4cccb8b01bedae7cf9

Summary:
- Document in the `README.md` how to build tests as part of the CMake build.

Closes https://github.com/facebook/folly/issues/1240
Pull Request resolved: https://github.com/facebook/folly/pull/1244

Differential Revision: D17927395

Pulled By: yfeldblum

fbshipit-source-id: 6b638ac807886b505b69063f2a47162f3f3fc8de

Summary: The standard only requires `To` to be trivially copyable, not trivial.

Reviewed By: yfeldblum

Differential Revision: D17916612

fbshipit-source-id: 80ae35672ea4664fe4204c8181ac6402065c4e03

Summary: Made a slight tweak to the collectAll benchmark for the coroutine implementation to avoid allocating additional coroutine frames.

Reviewed By: andriigrynenko

Differential Revision: D17917156

fbshipit-source-id: 890a2ab33eb53050930d4547119d30a9c161887e

Summary: std::chrono is less prone to error than specifying timeouts in `int` seconds.

Reviewed By: yfeldblum, mzhaom

Differential Revision: D17767787

fbshipit-source-id: 5bb23d3a78e6e798e7b10331dc416e24d5a8746d

Summary:
Synchronized::operator-> is dangerous because it's very easy to
implicitly acquire locks in ways that don't form a coherent locking
model. Replace uses of it in folly in preparation for removing or
marking the function deprecated later on.

Reviewed By: yfeldblum

Differential Revision: D17862465

fbshipit-source-id: 45d3b0d738941c3faa6d73418e79dcb8a1259e98

Reviewed By: yfeldblum

Differential Revision: D17892633

fbshipit-source-id: 1b4b2cffb040b1abf709ea2ccd4015426398dda0

Reviewed By: yfeldblum

Differential Revision: D17889050

fbshipit-source-id: 323a2a5796b4f06c2fe4c84a714a763aa3da4866

Summary: [Folly] Apply extra formatting rules beyond black.

Reviewed By: zertosh

Differential Revision: D17898403

fbshipit-source-id: 6d73c75a35513f138bcc0d734aada0c99cff54c7

Summary: [Folly] Apply `black` formatter to `.py` files.

Reviewed By: zertosh

Differential Revision: D17898404

fbshipit-source-id: b597b55b646e539a288d175e0b2db8111b5b103b

Reviewed By: yfeldblum

Differential Revision: D17889052

fbshipit-source-id: e9733e6ab31d01064660043b0f4edc31b0f5377e

Reviewed By: andriigrynenko

Differential Revision: D17749079

fbshipit-source-id: 44c2c6dd55fe5be033bc4a5139941b5e3a004a67

Summary: Like subscribeInline but does work on an executor and returns a subscription that can be waited on as a SemiFuture or cancelled

Reviewed By: andriigrynenko

Differential Revision: D17700281

fbshipit-source-id: 52b2c63af53e8f87d921cb0a0ab28da0a800a9fc

Summary:
This will add support to set and get thread name for Android.

`pthread_setname_np` was introduced back in NDK API level 9: https://stackoverflow.com/questions/15241869/pthread-error-in-ndk-build?fbclid=IwAR0yvyaC4KNA6D1GlgIofQSFIuZAgL7qDR5L6m5tkY6lv-R6uTvzreAiFp4

Backwards support added for setting current thread name using `prctl(PR_SET_NAME)`, when `pthread_setname_np` is not available (for `__ANDROID_API__ < 9`).

Currently, Android NDK does not support `pthread_getname_np` so `prctl(PR_GET_NAME)` is used for this.

Reviewed By: yfeldblum

Differential Revision: D17815151

fbshipit-source-id: 474caee070fad26f3e6b118307058d5506f0467b

Summary: [Folly] Move `ThreadName.cpp` macro defs outside C++ section, including outside `namespace ...` blocks.

Reviewed By: vitaut

Differential Revision: D17868541

fbshipit-source-id: a0964ce1f1c6322185f94b8162df4c0e6eaa84bf

Summary: [Folly] Simplify ASAN support in `folly/MicroLock.h`.

Reviewed By: mzlee

Differential Revision: D17842549

fbshipit-source-id: c9e89d8c69f8a291427a73fee12651353a5da4e4

Summary: It's possible for user code to be run in the ObserverManager thread outside of the refresh call (e.g. from Core destructor), so we can't rely on inManagerThread check to guarantee that Dependency recorder is active.

Reviewed By: yfeldblum

Differential Revision: D17805252

fbshipit-source-id: 5a858be0cf204da1342dc182e25797fd130c0458

Summary: See https://fb.workplace.com/groups/osssupport/permalink/2846876118694318/

Reviewed By: wez

Differential Revision: D17750243

fbshipit-source-id: 9e149df1f8e09203820f50d0fcac4a5cecf52e33

Summary: This is the first step towards removing `watchman/thirdparty/tap.{cpp,h}`

Reviewed By: chadaustin

Differential Revision: D17775680

fbshipit-source-id: d6ac32c3b2489e1713fb132b0bb46d848c56811f

Summary: This helps to squash out some flakiness

Reviewed By: pkaush

Differential Revision: D17804696

fbshipit-source-id: decd8e5dd37d802c62cae1168c4f4d72c0fc5c83

Summary: Same as regular groupBy

Reviewed By: ot

Differential Revision: D17843280

fbshipit-source-id: 33d74d7ed84b8c46509bf186bfa52e31d6284015

Summary: As it turns out, several of the `fizz` dependencies require it to have been built with tests enabled, so it's just easier to build them always, IIRC they only waste 1-2 minutes of time.

Reviewed By: lnicco

Differential Revision: D17837758

fbshipit-source-id: dd0c73b3aaf72831ce702dbcecd4e3ff627a4901

Reviewed By: wez

Differential Revision: D17494253

fbshipit-source-id: 45bab057e5cefd8f2808be96ba31814c5196051b

Summary:
Proxygen no longer uses `fbcode_builder` to run its tests, so whatever the purpose of D17158685, these `fbcode_builder` configs no longer affect Proxygen, and can be reverted to their original state.

Since the general design pattern for `fbcode_builder` has been to link everything as `.so`s, let's return to this (which helps fix Bistro's build).

Also, let's not waste time building & linking tests for libraries that are not the library under test. That is:
 - Before: The Bistro build also builds tests for wangle, proxygen, etc. This is a result of some accidental changes in D17158685.
 - After: We explicitly don't build test for any of the 4 dependencies here. This is OK because each project also has its own `fbcode_builder_config.py`, which **does** build tests.

This latter part should result in a build-time reduction.

Reviewed By: lnicco

Differential Revision: D17819858

fbshipit-source-id: 7cad1bed86b2f0c3934b0fc5d6fb33e6a2ee2695

Summary:
This diff introduces a data structure that keeps a set of, well any object,
but it's intended to cache compression contexts, e.g., `ZSTD_CCtx`es. These
objects can be expensive to allocate but cheap to reuse. E.g., HHVM was
spending 70% of its Zstd CPU allocating, memsetting, and freeing contexts
before it started using a structure like this.

Reviewed By: terrelln

Differential Revision: D15787721

fbshipit-source-id: bda33e9028c73c14435e18ce07cfbc8989263d98

Summary: [Folly] Namespace preprocessor names in `folly/CpuId.h`.

Reviewed By: LeeHowes

Differential Revision: D17780995

fbshipit-source-id: 29580e780a4f8639c4247b9af38f47182fc000bb

Summary:
[Folly] Fix `GroupVarint.h` includes and preprocessor namespacing.

* Always include everything rather than conditionally including things.
* Namespace as `FOLLY_HAVE_GROUP_VARINT`.

Reviewed By: LeeHowes

Differential Revision: D17780999

fbshipit-source-id: 109fa38794e312e0c5eba0f5bfab56853df59c92

Summary: s/#if _WIN32/#ifdef _WIN32/

Reviewed By: Orvid

Differential Revision: D17738798

fbshipit-source-id: cbfcf67c55b56a5e5453430d127acc3a7116814c

Summary:
[ Extend D17527441 changes from F15MapTest into F14SetTest ]
The current version of libc++ deallocates the existing capacity when calling operator=(initializer_list), even if the map is empty. This diff relaxes the expectations of F14's allocated memory tests (which fall back to the underlying STL std::unordered_map on some platforms) to accept this implementation.

Reviewed By: yfeldblum

Differential Revision: D17726849

fbshipit-source-id: 4757792a5aefe6d085b5d164ffe7b663f6078d9a

Summary:
We are seeing random segment fault originating from OpenSSL on macOS when
Mononoke fetching is enabled.

The cause is that on macOS we are actually linking against libcurl shipped with
the system instead of ours. That copy of libcurl is linked with macOS's
libcrypto instead of the one we compiles during Eden's build, and it seems that
version of libcrypto does not provide concurrency safety.

The solution is to build curl on macOS and make sure it is linked to our
OpenSSL that has the concurrency callbacks registered.

Reviewed By: wez

Differential Revision: D17657822

fbshipit-source-id: 85abdf3be10b3903a5efc6b3a91624c7258de790

Summary:
This diff teaches the generated Github Actions configuration to copy the
executable outputs from the leaf project into an artifacts dir, and then capture
the artifacts in the build.

This page has details on the artifacts mechanism used by Github Actions:
https://github.com/actions/upload-artifact

This page has the "Artifacts" link on the RHS where an example of the artifacts
can be downloaded:
https://github.com/facebook/watchman/pull/750/checks?check_run_id=244088199

Here's the actual download:
https://github.com/facebook/watchman/suites/247296465/artifacts/74686

And here's what the inside of that zip file contains for the watchman build:

```
$ find . -ls
49685444        0 drwxr-xr-x    6 wez              mygroup      192 Oct  1 18:50 .
49685487       16 -rw-r--r--    1 wez              mygroup     6148 Oct  1 18:51 ./.DS_Store
49685446        0 drwxr-xr-x    5 wez              mygroup      160 Oct  1 18:51 ./mac
49685501       16 -rw-r--r--    1 wez              mygroup     6148 Oct  1 18:51 ./mac/.DS_Store
49685453        0 drwxr-xr-x    3 wez              mygroup       96 Oct  1 18:50 ./mac/bin
49685455     5432 -rwxr-xr-x    1 wez              mygroup  2778500 Oct  2 01:02 ./mac/bin/watchman
49685454        0 drwxr-xr-x    7 wez              mygroup      224 Oct  1 18:50 ./mac/lib
49685457      296 -rwxr-xr-x    1 wez              mygroup   149096 Oct  2 01:02 ./mac/lib/libgflags.2.2.dylib
49685460     1072 -rwxr-xr-x    1 wez              mygroup   546348 Oct  2 01:02 ./mac/lib/libssl.1.1.dylib
49685459      272 -rwxr-xr-x    1 wez              mygroup   135524 Oct  2 01:02 ./mac/lib/liblz4.1.dylib
49685458      352 -rwxr-xr-x    1 wez              mygroup   176900 Oct  2 01:02 ./mac/lib/libglog.0.dylib
49685456     4888 -rwxr-xr-x    1 wez              mygroup  2501012 Oct  2 01:02 ./mac/lib/libcrypto.1.1.dylib
49685445        0 drwxr-xr-x    5 wez              mygroup      160 Oct  1 18:50 ./linux
49685486       16 -rw-r--r--    1 wez              mygroup     6148 Oct  1 18:50 ./linux/.DS_Store
49685448        0 drwxr-xr-x    3 wez              mygroup       96 Oct  1 18:50 ./linux/bin
49685450   196264 -rwxr-xr-x    1 wez              mygroup 100486648 Oct  2 01:16 ./linux/bin/watchman
49685449        0 drwxr-xr-x    4 wez              mygroup      128 Oct  1 18:50 ./linux/lib
49685451     3864 -rwxr-xr-x    1 wez              mygroup  1976888 Oct  2 01:16 ./linux/lib/libgflags.so.2.2
49685452     2208 -rwxr-xr-x    1 wez              mygroup  1127336 Oct  2 01:16 ./linux/lib/libglog.so.0
49685447        0 drwxr-xr-x    4 wez              mygroup      128 Oct  1 18:51 ./windows
49685513       16 -rw-r--r--    1 wez              mygroup     6148 Oct  1 18:51 ./windows/.DS_Store
49685461        0 drwxr-xr-x    5 wez              mygroup      160 Oct  2 01:44 ./windows/bin
49685464     7880 -rwxr-xr-x    1 wez              mygroup  4030976 Oct  2 01:44 ./windows/bin/watchman.exe
49685463      488 -rwxr-xr-x    1 wez              mygroup   249856 Oct  2 01:44 ./windows/bin/glog.dll
49685462      544 -rwxr-xr-x    1 wez              mygroup   278016 Oct  2 01:44 ./windows/bin/gflags.dll
```

The `main.yml` file was updated by running:

```
$ opensource/fbcode_builder/getdeps.py generate-github-actions --output-file watchman/.github/workflows/main.yml watchman
```

Pull Request resolved: https://github.com/facebook/watchman/pull/750

Test Plan: See description above

Reviewed By: pkaush

Differential Revision: D17705148

Pulled By: wez

fbshipit-source-id: 4f3c466180f5a1cb9fa31a9b3b3f117876f8b89d

Summary:
Production-enabled assertions have shown value in detecting
a variety of issues that should be impossible but are observed to
occur. This diff adds some checks to F14 that may fail under some types
of memory corruption, tag missearch, or hash miscomputation.

Reviewed By: yfeldblum

Differential Revision: D17739592

fbshipit-source-id: 92c9839ed5dab030350408d704a01c97573e3123

Summary: In Cython, use `from folly.cast cimport down_cast` to import the function.

Reviewed By: yfeldblum

Differential Revision: D17652305

fbshipit-source-id: 6b038c5ac6c2a8ecd8e95f33ae3a37647a2bfdff

Summary: [Folly] Fix missing qualification in `FOLLY_SAFE_DCHECK` macro.

Reviewed By: nbronson

Differential Revision: D17747688

fbshipit-source-id: 1bab5770891c900252f767252b5d7769e209bcb1

Summary:
[Folly] Export `folly::json::parse_error` v.s. having it be a hidden type.

* Move class body to `.h`.
* Leave helper function, previously the constructor, in anonymous namespace in `.cpp`.

Reviewed By: vitaut

Differential Revision: D17578773

fbshipit-source-id: 0d50fdf662bbf67e844ff0ec9ef24975cea92f62

Summary:
We were troubleshooting an issue with the eden tests on windows
where the boost dlls where not being found during gtest discovery.

When we compute the environment, we were only including INST/bin in the
PATH on windows.  On Windows, the dlls are searched for in the PATH, and
since boost installs those into its `lib` dir we were missing those.

This diff causes `lib` dirs to get added to PATH on windows in the same
manner that we would add them to `LD_LIBRARY_PATH` on linux.

Reviewed By: pkaush

Differential Revision: D17694542

fbshipit-source-id: 143a907e6d30d8c12360caa43c8d9c26ff8c88c6

Summary:
On linux we use `patchelf` to manipulate dynamic deps but it
isn't guaranteed to be installed everywhere.  We have a manifest file
that describes how to build it, but so far nothing has told getdeps
that it should build it.

This diff updates the ELF dep munging code to literally run
`getdeps.py build patchelf` and then use that patchelf binary to
manipulate the object files.

Refs: https://github.com/facebook/watchman/pull/750

Reviewed By: pkaush

Differential Revision: D17705351

Pulled By: wez

fbshipit-source-id: 358ef239edb389fbd51fa023ff553963aa80b6c7

Summary: Mobile phones have more like 16 CPUs and less like 128 CPUs.

Reviewed By: yfeldblum

Differential Revision: D16151292

fbshipit-source-id: 87caed64d9a874f71e85ee2842194405e43568a3

Summary: [Folly] Dead Code: `PriorityMPMCQueue`.

Reviewed By: LeeHowes

Differential Revision: D17718372

fbshipit-source-id: c79c376abadf7149b94d343cd6705f030fd71666