Summary: [Folly] Simplify the fallback implementations of `constexpr_strlen` and `constexpr_strcmp` by taking advantage of C++14 `constexpr` syntax.

Differential Revision: D23416900

fbshipit-source-id: 93a969282faa61b3c9ff8e75519ad4e6edd71e4e

Summary: TSAN just needs more stack doing this...

Reviewed By: yfeldblum

Differential Revision: D23484864

fbshipit-source-id: e5412982349f73f8ead795403dfbde2830f4e5fd

Summary: Apparently the code says, being signal unsafe is OK because the signal is created with raise(). So let's just skip that test under TSAN.

Reviewed By: yfeldblum

Differential Revision: D23484012

fbshipit-source-id: 697234b9f57db97c6c6aaf8131058d3ecec3d059

Summary:
To preserve void type in roundtrip
Doing this generically is pretty gross (you need to check if awaiter_type<decltype(co_viaIfAsync({}, SemiAwaitable))> has a member await_resume_try), while the cost of adding explicit overloads is low as there are only two types we care about, so I chose to do it that way.

Reviewed By: yfeldblum

Differential Revision: D23407270

fbshipit-source-id: cc952e2d8fa4297dbe363e22e99192fdf858134f

Summary:
The Timekeeper parameter can be used to pass in manually-controlled time-sources
for testing purposes if required.

Reviewed By: yfeldblum

Differential Revision: D23386677

fbshipit-source-id: bea09292b00f6cd018568d26e5409d2c7ff01dbe

Summary: [Folly] Test `constexpr_strlen`, `constexpr_strcmp` fallback implementations alongside the main implementations, since the main implementations may fall back to the fallback implementations on some platforms but not on others, and we may only be testing on the other platforms.

Differential Revision: D23432301

fbshipit-source-id: 271705cb8c2b1ab6d11c1be20e2c3023cacab583

Summary: [Folly] Cut `FOLLY_CREATE_HAS_MEMBER_FN_TRAITS` since it is unused and does not match the current invoker model, replacing uses which need it with `FOLLY_CREATE_MEMBER_INVOKER`.

Reviewed By: vitaut

Differential Revision: D23371070

fbshipit-source-id: 7fb0f5af21321a5056e06933ebd364a0a48a8fa1

Summary: Reduce boilerplate when defining simple coroutines, e.g. in tests

Reviewed By: yfeldblum

Differential Revision: D23404552

fbshipit-source-id: a19e9cb6640e3897d3c166499014ebe4c19fbf04

Summary: D9312236 (https://github.com/facebook/folly/commit/bc16b096b1f6659e29379a650998bbfcf0c03eca) made these tests conditional on using libstdc++, but the header that defines the macro is not included prior to the `#ifdef`, so the tests (and benchmarks) are disabled unconditionally.

Reviewed By: yfeldblum

Differential Revision: D23469536

fbshipit-source-id: 2ab0b2d28748419d88e946eff9b09b98d361dedb

Summary: [Folly] Revise `is_transparent_v` as a variable and as eager, and atop `is_detected`, and `is_transparent` as a type and as deferred.

Reviewed By: Mizuchi

Differential Revision: D23367991

fbshipit-source-id: be30184b04e2a1977db3faccd57e947dd33282ce

Summary:
Change name of warning_list_too_large to hazptr_warning_list_too_large for consistency with other hazptr warning functions.

Add missing  FOLLY_EXPORT.

Reviewed By: yfeldblum

Differential Revision: D23436826

fbshipit-source-id: 149c62c9d1cd3320ef525a90c0b591b274228054

Summary: [Folly] `is_detected`, for a common pattern around `void_t`, backported from Library Fundamentals TS v2.

Reviewed By: Mizuchi

Differential Revision: D23367990

fbshipit-source-id: 3a0e9a5b7eb668f872ce699757e32bb620bb5404

Summary: Add support for microsecond intervals in the function scheduler

Reviewed By: arushiagg

Differential Revision: D23433411

fbshipit-source-id: 39d201feaaed8007ec880a799129ed94bedd827a

Summary: Add io_uring registered buffers support

Reviewed By: kevin-vigor

Differential Revision: D23421043

fbshipit-source-id: b9c6a4bbd7a6b6cc580b1e3f64320d9e59d04ab2

Summary: [Folly] Revise is_instantiation_of_v as a variable and as eager, and is_instantiation_of as a type and as deferred.

Reviewed By: Mizuchi

Differential Revision: D23367989

fbshipit-source-id: bf6ebd74b8e7758818dfcebd04152e1297bc99e4

Summary: These lightweight functions are useful on their own, but were tied to `Benchmarking.h` & all their dependencies.

Reviewed By: yfeldblum, ot

Differential Revision: D20239087

fbshipit-source-id: 644601b6f869191db1492d0738f3af723b9e0f4b

Summary: Fix overspecified LoggerTest.

Reviewed By: yfeldblum, simpkins

Differential Revision: D23425421

fbshipit-source-id: ecfd7d0e73555b3a94a81b54ffd1287bf9664697

Reviewed By: xavierd

Differential Revision: D23434438

fbshipit-source-id: 813f987cf62e72c0b6704b31e6e9168006735b6f

Summary: Original commit changeset: 10f18d7b774c

Reviewed By: arushiagg

Differential Revision: D23431208

fbshipit-source-id: d2c79f81fd0ada202dc2eaa96b0f061828ca107e

Summary: Many unit tests ended up already depending on the scheduling order. Relax the logic to only reschedule once we reach a high nesting depth.

Reviewed By: iahs

Differential Revision: D23415806

fbshipit-source-id: dde682293ded0061cf331fa5f46e1f6b55928a3e

Summary:
std::iterator was deprecated in C++17, so define the iterator trait
properties directly. This fixes warnings during compilation with Clang
on Windows.

Reviewed By: yfeldblum

Differential Revision: D23353495

fbshipit-source-id: 7c6c0b7fb175251260e5b519ce98bd679b6c99c4

Summary: Add support for async range submit

Reviewed By: yfeldblum

Differential Revision: D23389493

fbshipit-source-id: 7171893a2eeccc20fcdd625e98f88d365027c930

Summary: TSAN breaks symmetric transfer behavior in compiler. Work around it by rescheduling work on executor when possible.

Reviewed By: yfeldblum

Differential Revision: D23391328

fbshipit-source-id: 7b25a0c89664ca14114f8ae0dc650ff9bb786fe1

Summary: Switch from VLA to folly::small_vector

Reviewed By: yfeldblum, ot

Differential Revision: D23391426

fbshipit-source-id: c6c61f3f0eef5b6e71ad3a639fcfdb4fa1b7268e

Summary: Add support for microsecond intervals in the function scheduler

Reviewed By: yfeldblum, Mizuchi

Differential Revision: D23153179

fbshipit-source-id: 10f18d7b774c47659fe8191f8d92dca341e1cf97

Summary: [Folly] Remove the guard around `tag`, the inline variable of type `tag_t`.

Reviewed By: Mizuchi

Differential Revision: D23370037

fbshipit-source-id: 59a48d834904b7e503f807c62fff8534568c9a0a

Summary: This diff makes folly::coro::co_invoke work with folly::coro::Generator.

Reviewed By: yfeldblum

Differential Revision: D23332912

fbshipit-source-id: b3e25d160a94aed8892bf55ad5007f4018786e47

Summary:
Add a method for querying the number of remaining tasks
that have been added to an AsyncScope but that have not
yet completed.

This can be useful for implementing some load-shedding
strategies based on the current number of active tasks
added to a scope.

Reviewed By: andriigrynenko

Differential Revision: D21461637

fbshipit-source-id: 628c236e0c99fa952e63f84366186246e5286bc8

Summary: Adjust low level deps in OSS builds to use standard `CMAKE_CXX_STANDARD` variables to control std level in cpp builds.

Reviewed By: yfeldblum

Differential Revision: D23333713

fbshipit-source-id: cd76712d6b045f1d0aff30d4874d9bf0ce6f1e01

Summary:
[Folly] Use C++ v.s. the preprocessor to check for mobile in `IOBuf`.

Using C++ allows the compiler, when compiling for any platform, to see the full code for every platform and to typecheck and report errors.

Reviewed By: aditya7fb

Differential Revision: D23365674

fbshipit-source-id: 9cfe048a3114be3d6ef4522e279e19fb21f50a17

unconditionally build symbolizer sources even if FOLLY_USE_SYMBOLIZER is unset or the platform is non-ELF

Summary:
Rather than conditionally include the folly symbolizer sources in the
CMake build, always build them, and add appropriate dependency defines
to conditionally enable functionality.

Reviewed By: yfeldblum

Differential Revision: D22970595

fbshipit-source-id: 957242b7fde28584edd78a1a6dbe9f830e98e726

Summary: These tests time out under TSAN and there's not much value to run them under TSAN because the tests are single-threaded.

Reviewed By: yfeldblum

Differential Revision: D23302147

fbshipit-source-id: 6fc8bd3e29c9cde72bfa85a14fd7726850540285

Summary: Originally we were only checking for iOS or macOS, but this logic also needs to be done for watchOS and tvOS as well.

Reviewed By: Orvid

Differential Revision: D23302842

fbshipit-source-id: 40806b3c45194b964fe14d0d00a092a2c96e9882

Summary: Define FOLLY_ELF_NATIVE_CLASS if not defined and __ELF_NATIVE_CLASS is available

Reviewed By: yfeldblum

Differential Revision: D23307593

fbshipit-source-id: bb4b7a82a58a9ba9d4725dd770a2e5b7109b0318

Summary: This is just a typo I noticed while breaking some of my own code. :)

Reviewed By: andriigrynenko

Differential Revision: D23293835

fbshipit-source-id: a99abe57ab6f63e98c29e670f6ba3da05b688253

Summary: Add compile support for platforms that define ElfW

Reviewed By: yfeldblum

Differential Revision: D23305597

fbshipit-source-id: fc94e7f3023389cc5a03862dba7c3dc05c1dbeea

Summary: Remove unused include of sorted_vector_types.h in Request.h

Reviewed By: yfeldblum

Differential Revision: D20903094

fbshipit-source-id: cf54ebabc102789e5629d84a138a1caf1ffa396b

Summary: This patch adds support for `std::variant` to `folly::variant_match` but without including `<variant>`.

Reviewed By: yfeldblum

Differential Revision: D23196572

fbshipit-source-id: 9d5b519958b04c13cc024d393247c73cec00ac67

Summary:
We should only be capturing `folly::RequestContext` in HHWheelTimer's callback
objects (already  happens). And avoid capturing it in underlying AsyncTimeout.

Notice that `AsyncTimeout::scheduleTimeout`/`scheduleTimeoutHighRes` APIs capture
current `folly::RequestContext` and `AsyncTimeout::cancelTimeout`
releases the captured `folly::RequestContext`

Now, the way HHWheelTimer works, it re-uses one instance of AsyncTimeout for
multiple timeouts. This opens up possibility for leaking lifetime of RCTX.
Imagine first  request A and then B schedule timeouts using same HHWheelTimer
instnace. A's RCTX is captured by underlying AsyncTimeout. Next, request A is
complete and we need to cancel its timeout. Notice, however that A's RCTX will
not be destroyed as long as B is still running. That's the lifetime management
leak.

Reviewed By: jordalgo, andriigrynenko

Differential Revision: D23260733

fbshipit-source-id: 0bdf79db40d34d6682e89e87ce30811ffccc8cbf

Summary: Remove implementation based on read locking (replaced by implementation based on hazard pointers).

Reviewed By: yfeldblum

Differential Revision: D20881677

fbshipit-source-id: da89eee6a92fa34fa1c111a421bf5368873ccd57