Summary: This diff factors out some of the logic needed in the stacked diff D21628842. We want `RocketClientChannel::sendRequestResponse` to work without a fiber if the caller is not already on a fiber, which means we cannot only use `Baton::TimeoutHandler` for the request's timeout callback.

Reviewed By: iahs

Differential Revision: D21628871

fbshipit-source-id: 2e739f205fcb0a255108fa88f94107378a1bab49

Summary:
In order to use the Python 3 streaming thrift client on platforms that
don't support coroutines, conditionally define anything that depends
on coroutines.

Reviewed By: yfeldblum

Differential Revision: D21692900

fbshipit-source-id: 9f26d598097181ae43d1ff377a22b1c2f789321e

Summary: Add missing includes of `folly/synchronization/Baton.h`.

Differential Revision: D21716396

fbshipit-source-id: 8c8fb818f3083b4fe04fd1c62923d7ba698dcedd

Summary: Add AsyncUDPSocket::maxReadsPerEvent_ support

Reviewed By: yfeldblum

Differential Revision: D21509991

fbshipit-source-id: 5c4f939c1cfdda8711864df3b5f5c58439f8d7bf

Summary: [Folly] Compare `exception_wrapper::class_name()` to `demangle(typeid(...))` in tests v.s. comparing it to string literals since the actual result of `...::class_name()` depends on the platform and whether `libiberty-dev` is available.

Differential Revision: D21711569

fbshipit-source-id: b2289d89923d6775c7e806eff9c3732ad37a0218

Summary: [Folly] Prefer `EndsWith` matcher in `exception_wrapper` test so that, in case of failure, the non-matching input will be shown.

Differential Revision: D21708674

fbshipit-source-id: 022f7d64a030417b80b8796ae3d78534295509fc

Summary: [Folly] Comments in `folly/synchronization/Lock.h`.

Differential Revision: D21689050

fbshipit-source-id: 65ffa2cf9bf3afe8740ae0c4a0d529c706397dae

Summary: [Folly] Extract utf-16 surrogate-pair helpers from `folly/json.cpp` into `folly/Unicode.h`.

Reviewed By: luciang

Differential Revision: D21634400

fbshipit-source-id: 64d15e79fe19cce5f5c9c38837d4663209b5f888

Summary: Add tracing to SemiFuture destruction that is potentially work-dropping.

Reviewed By: yfeldblum

Differential Revision: D21671142

fbshipit-source-id: 8e3e733d9a0845b00fe7ccf465e9c817a10fee59

Summary:
Now that we've deployed the new eden build with globfiles
support, we can enable the use of eden prefetch in the getdeps
build when running inside an EdenFS mount on Windows.

Reviewed By: fanzeyi

Differential Revision: D21692689

fbshipit-source-id: b42e778901976cf0385ec31056c227b2049162dc

Summary:
`folly::expected_detail::Promise<Value, Error>` won't build with exceptions
turned off (e.g. by passing `-fno-exceptions` on Clang's command line) because
its `unhandled_exception()` says `throw;`.  This diff replaces the `throw;`
with a call to `folly::rethrow_current_exception();`.

Reviewed By: yfeldblum

Differential Revision: D21682605

fbshipit-source-id: 294752590d54b0671395982ccdeb0386a742c01e

Summary: [Folly] Use `RequestToken` in `RequestEventBase` to speed up lookup.

Reviewed By: zhxchen17

Differential Revision: D21529465

fbshipit-source-id: eaaef7b48be2c5a8d76fb5f4a5293f7db7e68bed

Summary: [Folly] Fix technical typo in checking hw checksum support, but which makes no practical difference.

Differential Revision: D21689112

fbshipit-source-id: 8ad71d20a561f4bbf5c413ce94e7bec227d9d940

Reviewed By: yfeldblum

Differential Revision: D21666740

fbshipit-source-id: 96975e777df0745f343c5b722f1d8c05bb8ac32e

Summary: [Folly] Tweak `BlockingContext` in various ways.

Differential Revision: D21657789

fbshipit-source-id: 4b03b3b43dddc0e9011a7594001994f2594a1a5b

Summary:
[Folly] Lock utilities: `upgrade_lock`, `transition_to_shared_lock`, `transition_to_upgrade_lock`, `transition_to_unique_lock`, `try_transition_to_unique_lock`.

Note: `std::shared_mutex` does not have an upgrade state or any atomic transitions; there is no `std::upgrade_lock`; and `std::shared_lock` does not have a constructor from `std::unique_lock`.

Reviewed By: simpkins, nbronson

Differential Revision: D15532568

fbshipit-source-id: d32f387b26b57539857922c3090dc75ffcaaa538

Summary:
Migration from Future-returning executor-erasing collectX forms to
SemiFuture-returning forms, that are less risky in particular with coroutines.

Earlier changes added collectXSemiFuture and collectXUnsafe as a migration
path. We then migrated collectX callsites to collectXSemiFuture or
collectXUnsafe and switched the implementation of collectX to the SemiFuture
form.

This diff removes collectXSemiFuture completely.

Reviewed By: yfeldblum, mpark

Differential Revision: D21631886

fbshipit-source-id: c7b296d51f30c8b51ab0c7d06b1ce62c8cdd28d5

Summary:
`folly::detail::OptionalPromise<Value>` won't build with exceptions turned off
(e.g. by passing `-fno-exceptions` on Clang's command line) because its
`unhandled_exception()` says `throw;`.  This diff replaces the `throw;` with a
call to `folly::rethrow_current_exception();`.

Reviewed By: yfeldblum

Differential Revision: D21655976

fbshipit-source-id: 5f431372f2494a09f98e3b8c36a94e8475efff29

Summary:
This fails to build on win32 platform with:
```
xplat\folly\portability\pthread.cpp(142): error C2664: 'HANDLE CreateThread(LPSECURITY_ATTRIBUTES,SIZE_T,LPTHREAD_START_ROUTINE,LPVOID,DWORD,LPDWORD)': cannot convert argument 3 from 'DWORD (__cdecl *)(void *)' to 'LPTHREAD_START_ROUTINE'
```

This seems to fix it.

Reviewed By: Orvid

Differential Revision: D21623386

fbshipit-source-id: 1b18a74bd71ffc75f34a92074e07f3d69742c07d

Summary: [Folly] Small simplification of `AsyncSocket` read loop.

Differential Revision: D21514325

fbshipit-source-id: 0af27205b4aa2807a800430e8a2b3dea36356970

Summary: Add io_uring_submit_and_wait call

Reviewed By: yfeldblum

Differential Revision: D21653382

fbshipit-source-id: 945aa877a30b3c6431089a113ece5999d1217eb4

Reviewed By: yfeldblum, luciang

Differential Revision: D21656746

fbshipit-source-id: 5e19d72ccd524926c698b8814cc6c8f2c6133565

Summary: fsync the temp file

Reviewed By: yfeldblum, kevin-vigor

Differential Revision: D21668049

fbshipit-source-id: 85825f81dfbe10a452f7f946133bb3d8993850f8

Summary: [Folly] `rethrow_current_exception`, a `-fno-exceptions` compatibility wrapper for `throw;`.

Reviewed By: ispeters

Differential Revision: D21656269

fbshipit-source-id: 8f37fe71c6255162b8f05268cae04ac5927013d7

Summary:
gcc-6.5 on OS X <= 10.6 complains about the `\r` when this code path
is enabled. I don't think we officially support `__i386__`, but I want to
backport the patch from zstd. https://github.com/facebook/zstd/pull/1418

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum, Orvid

Differential Revision: D13104652

fbshipit-source-id: 737a68253c7d90c3a1cc026069b048551cb5ced9

Summary:
If an error is thrown when formating arguments for a log message, use
`folly::exceptionStr()` to format the exception instead of just `ex.what()`.

I changed all of the tests that verify the results of these strings to use a
regular expression, as `folly::exceptionStr()` produces different results in
different platforms, and does not always demangle type names.

I also included a minor change to increase a timeout in
AsyncFileWriterTest.cpp, as I saw this timeout fail spuriously once in my
testing.

Reviewed By: yfeldblum

Differential Revision: D21635680

fbshipit-source-id: 749ef48deb59af1f2faef0158e0291838e09fc38

Summary:
Fix the issue that there may be other tags like DW_TAG_lexical_block between DW_TAG_subprogram and DW_TAG_inlined_subroutine.

Also increase the maximum inline location info per frame since previous value 3 is too small.

Refactors the code to set file and line for inline functions.

Reviewed By: luciang

Differential Revision: D21250080

fbshipit-source-id: f52dc74ee5c144aa26723546b48486f8a5250f19

Summary: Fix uninitialized maxSubmit_, maxGet_ member variables

Reviewed By: danobi

Differential Revision: D21645171

fbshipit-source-id: 094ba7b045010954fdebc249318191f956f5b7b2

Summary:
This updates the logging code so that it is possible to include `folly/xlog.h`
and write log statements in code that is compiled with `-fno-exceptions`

The code for parsing log configuration strings does still use exceptions in
some of its config parsing logic.  It shouldn't be too difficult to disable
that in a subsequent diff, but for now this change at least makes it possible
for calling code to write log messages.

Reviewed By: yfeldblum

Differential Revision: D21630914

fbshipit-source-id: ce9ed422f40066e57433a85182e1a8fc6d8628db

Summary:
This fixes a race condition detected by ThreadSanitizer.

The thread list is protected by a mutex, but individual structs in the list are not protected, leading to racy access to two of their fields. This diff makes the fields atomic.

Reviewed By: yfeldblum

Differential Revision: D21484748

fbshipit-source-id: a981419f47a2aebaf1d40b23e9c4967cf2104aaa

Summary: Remove PollIoBackend inline submit

Reviewed By: danobi

Differential Revision: D21625033

fbshipit-source-id: 02ee55e64a2538c6a2392ea70912f4ae9b642963

Summary:
The current stack trace formatting is based on repeated string appends with newlines. This change adds more control so that we can produce file and line information only, without unnecessary newlines.

New format:
  ./folly/experimental/symbolizer/Symbolizer.h:77
  ./folly/experimental/symbolizer/test/StackTraceTest.cpp:209
  ./folly/experimental/symbolizer/test/StackTraceTest.cpp:213
  ./folly/experimental/symbolizer/test/StackTraceTest.cpp:258

Reviewed By: yfeldblum

Differential Revision: D21562670

fbshipit-source-id: 7d05605cbda686e2f1c87577647c7ab7581f8580

Summary:
adds ensureCleanupAfterTask()

takes a SemiFuture<T> task and a SemiFuture<Unit> cleanup.

returns a SemiFuture<T>

always starts cleanup after task completes. stores the result of the task and replays it after the cleanup completes.

cleanup is not allowed to fail.

Reviewed By: yfeldblum, andriigrynenko

Differential Revision: D21481825

fbshipit-source-id: 901a91c25f7b2b4fa794a590a5433e0fad27d168

Summary:
CpuLocalBuffer need extend alignment, which isn't honored by std::vector's default allocator due to compiler bug

  http://open-std.org/JTC1/SC22/WG21/docs/papers/2012/n3396.htm
  https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65122
  https://bugs.llvm.org/show_bug.cgi?id=22634

the fix is to use custom allocator to honor extend alignment requirement.

Reviewed By: yfeldblum

Differential Revision: D21405041

fbshipit-source-id: 53cfe1bfd66580990c8a1a0c5f0c09f6651bda24

Summary:
[Folly] Fill `reentrant_allocator` member types and functions for situations which fail to indirect via `std::allocator_traits`, such as the former implementation of libstdc++ `std::basic_string`.

May help to address https://github.com/facebook/fboss/issues/86.

Differential Revision: D21608091

fbshipit-source-id: 020ac3bd37b27a08dd7c8113a77979d0ba21a8fc

Summary:
Allows attaching a BPF script to observe tasks behavior

Sample script, attaching those probes to a test binary (./buck-out/gen/common/services/cpp/test/thrift_2_async_server) is provided.

Reviewed By: yfeldblum

Differential Revision: D21526163

fbshipit-source-id: e976ddada1921c8c904d65aa9a558bbb45bf158f

Summary:
Adds a new CoInvoke() helper function that should be used instead of ::testing::Invoke() when defining mock methods using coroutine lambdas.

Use of Invoke() in a GMock definition that calls a coroutine-lambda that
contains captures will result in the returned Task holding a dangling reference
to a copy of the lambda.

The CoInvoke() helper instead, ensures that the coroutine created by the
lambda holds on to a reference to a copy of the lambda that is kept alive
until the coroutine completes by invoking the lambda using the folly::coro::co_invoke()
utility function instead of directly calling operator().

Reviewed By: andriigrynenko

Differential Revision: D21578404

fbshipit-source-id: 3322740efd00596c2311530a166ef2d5301c6b89

Summary:
I'm doing this mostly so that we can avoid using git
to fetch the sources.

Reviewed By: chadaustin

Differential Revision: D21508201

fbshipit-source-id: 54d4635d8938659bea962e90bd829d237f1ed221

Summary:
We use drive letter substitutions to workaround Windows
filename length limitations.  On my personal Windows system running
python 3.8.2 realpath inside an ssh session manages to resolve to
the full filename which causes the boost build to fail.

Avoid that!

Reviewed By: chadaustin

Differential Revision: D21507851

fbshipit-source-id: 1220c1c85d2124ddc51f42cefff2ce00e10c55c9

Summary: [Folly] Avoid inlining `Cursor` slow paths. These are already extracted to separate functions, but the compiler will still aggressively inline them.

Differential Revision: D21392842

fbshipit-source-id: 2b045ae9c5188315b938de984730ad2051237cf5