Summary: [Folly] Cut unused `#include`s in `folly/experimental/symbolizer/ElfCache.h`.

Reviewed By: Orvid

Differential Revision: D20482493

fbshipit-source-id: 426ebe0aa55e116e3f3c8095b0c9d0f1babdb354

Summary:
This enables fetching blobs from the LFS server. For now, this is limited to
fetching them, but the protocol specify ways to also upload. That second part
will matter for commit cloud and when pushing code to the server.

One caveat to this code is that the LFS server is not mocked in tests, and thus
requests are done directly to the server. I chose very small blobs to limit the
disruption to the server, by setting a test specific user-agent, we should be
able to monitor traffic due to tests and potentially rate limit it.

Reviewed By: DurhamG

Differential Revision: D20445628

fbshipit-source-id: beb3acb3f69dd27b54f8df7ccb95b04192deca30

Summary: Helper observer which only triggers updates when the value changes.

Reviewed By: bithree

Differential Revision: D20521319

fbshipit-source-id: 77e45d92f710b1701552cf29445f44aa9d9487f4

Summary: Correct use of portability macro.

Reviewed By: yfeldblum, manderyao

Differential Revision: D20520392

fbshipit-source-id: b21fb13aa7a523db21a506b71e65047edbb17684

Summary: Fix two small warnings when building AsyncUDPSocket on macOS.

Reviewed By: fanzeyi

Differential Revision: D20525411

fbshipit-source-id: 39cd84364413d434d261c17c4c8a87e31ac75a42

Summary:
Add support for creating an EventBaseManager with a custom backend factory method

(Note: this ignores all push blocking failures!)

Reviewed By: kevin-vigor

Differential Revision: D20513736

fbshipit-source-id: 62edc876cd1c0667bd7beb85a3d6fbd9a5a03ebf

Return 0(success) in EventBaseEvent::eb_event_base_set if we're trying to use a non libevent backend

Summary: Return 0(success) in EventBaseEvent::eb_event_base_set if we're trying to use a non libevent backend

Reviewed By: kevin-vigor

Differential Revision: D20513609

fbshipit-source-id: 8329c614f728a86d1bd5267652c39c8d4f54f6cd

Summary: Allow the WTCallback to be used with timer managers that have timeoutExpired methods

Reviewed By: kevin-vigor

Differential Revision: D20503031

fbshipit-source-id: df91f1e2531f5c54943d3540bdf7c3d357c9fda1

Summary:
Sometimes it fails to throw exception in [Codel::setOptions](https://github.com/facebook/folly/blob/master/folly/executors/Codel.cpp#L109), since it failed the check `interval <= delay`.

The reason is that both interval and delay are [POD](https://github.com/facebook/folly/blob/master/folly/executors/Codel.h#L80-L81), thus both are not initialized by default.

Using them without initialization is UB. In x86, they will have random value (since x86 doesn't have trap representation), thus sometimes it passes, sometimes it fails.

Based on comment, it looks like the intention is copying the `options` from default initialized `Codel`.

Reviewed By: amlannayak

Differential Revision: D20499449

fbshipit-source-id: e12de0b42c02a8bf6379ba7fd224e0ae173945f0

Summary:
Add eb_signal_set, eb_timer_set methods to be in sync with libevent

(Note: this ignores all push blocking failures!)

Reviewed By: kevin-vigor

Differential Revision: D20513498

fbshipit-source-id: be8d5d0ca362bdaa86cc161f481aea93cc757c75

Summary: A thread-local query for the current executor. Grounding feature for logging operations.

Reviewed By: andriigrynenko

Differential Revision: D20070133

fbshipit-source-id: e320d2a3d97744b91c07a6060708e5cefc517cb7

Summary: Make the hazard pointer-based implementation of request context the default one by setting `folly_reqctx_use_hazptr` to true by default.

Reviewed By: yfeldblum

Differential Revision: D19145252

fbshipit-source-id: 5dd68fb92561685a6ee35d8b3b03a1dcf7e1e356

Summary:
while compiling on windows see duplicated symbols:
```
lld-link: error: duplicate symbol:
public: static char const *const folly::dynamic::TypeInfo<
class std::basic_string<char, struct std::char_traits<char>,
class std::allocator<char>>>::name
in buck-out\dev\gen\crypto\cat\cpp\tests\crypto_auth_token_util_test#compile-CryptoAuthTokenUtilTest.cpp.obj1f5bc0bc,windows-x86_64\out.obj
and in libdynamic.lib(out.obj)
```

Reviewed By: yfeldblum

Differential Revision: D20426321

fbshipit-source-id: 4e0346c624ad12561adb14f3a2e5f6e15bbbba26

Summary:
This workaround is no longer necessary for a Clang that includes
patch https://reviews.llvm.org/D76118.

Reviewed By: ispeters, lewissbaker

Differential Revision: D20486353

fbshipit-source-id: cab137ed557ba8aa6ec86ec7011cc4fc7c46fe82

Summary:
building on windows fails:
```
buck-out/cells/fbsource/gen/xplat/third-party/glog/glogWindows#header-mode-symlink-tree-only,headers\glog/logging.h:698:32:
error: comparison of integers of different signs: 'const unsigned long long' and 'const int' [-Werror,-Wsign-compare]

buck-out/dev/gen/folly/synchronization/hazptr#header-mode-symlink-tree-only,headers\folly/synchronization/HazptrObj.h:397:13:
note: in instantiation of function template specialization 'google::Check_EQImpl<unsigned long long, int>' requested here
            DCHECK_EQ(reinterpret_cast<uintptr_t>(p) & 7, 0) << p << " " << i;
```

Reviewed By: yfeldblum

Differential Revision: D20482798

fbshipit-source-id: 4b661121401890cec113905fc6b53cd9189fcca0

Summary:
e.g. debian doesn't seem to have it
```
$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux bullseye/sid"
NAME="Debian GNU/Linux"
ID=debian
HOME_URL="https://www.debian.org/"
SUPPORT_URL="https://www.debian.org/support"
BUG_REPORT_URL="https://bugs.debian.org/"
```

Reviewed By: mjoras

Differential Revision: D20483097

fbshipit-source-id: 722397ff994336884ed2e5bbf8fe517d4dcf4e6c

Summary:
clang being more strict with obsolete C++14 api, has
completely disabled them in this context.
Pull Request resolved: https://github.com/facebook/folly/pull/1317

Reviewed By: luciang, markisaa

Differential Revision: D20154780

Pulled By: yfeldblum

fbshipit-source-id: 1ff36fecd3406802c3f393dfdd5dbe2f30656567

Summary: Retrying was modified to support SemiFuture returning policy and function, but incorrectly handled the return type propagation. Fix the problem and add a test to verify.

Reviewed By: yfeldblum

Differential Revision: D20462982

fbshipit-source-id: 97b4dad6d83dbbfe7f1846b457bf915c14b9f31a

Summary:
Conv.h's detail::digitsEnough was not decomposing to a constexpr on iOS/Mac toolchains, which resulted in the following call becoming a runtime VLA:

```
char buffer[detail::digitsEnough<unsigned __int128>() + 1];
```

Update to use `numeric_limits<>::digits10`, which allows this function to evaluate at compile-time on iOS/Mac.

Reviewed By: yfeldblum

Differential Revision: D20440659

fbshipit-source-id: d086e367eec0d3b2f35465525cb7406e746e6df7

Summary: Unqualify nearly all uses of `folly::AsyncUDPSocket::ReadCallback::OnDataAvailableParams` since nearly all uses already have `OnDataAvailableParams` in scope.

Differential Revision: D20450063

fbshipit-source-id: c0fd49a7eace44a6edc8086762c44753224788dd

Summary:
This code is new in 9.3.0, introduced upstream with:
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ed920373
Unless we qualify folly::reduce() we get the clash
in P127472223 when running the test plan.

Reviewed By: meyering

Differential Revision: D20461173

fbshipit-source-id: 41b21e9215571da2cbd2ef7f817e2d9999083033

Summary: [Folly] `FOLLY_SSSE`, for testing compiler mode support for SSSE3 intrinsics.

Reviewed By: markisaa

Differential Revision: D20414435

fbshipit-source-id: 077a78f880ea8dce44f1aced38a6cca08cdd1f65

Summary: [Folly] Move remove_reference_wrapper to coro traits, since this is not a language-level trait and is there to be used in the coro library.

Reviewed By: iahs

Differential Revision: D20301017

fbshipit-source-id: aa78488cc5138e6ade9dcbc99ec1b75b65c74c78

Differential Revision:
D20443631

Original commit changeset: 03e8210a64a3

fbshipit-source-id: 42621768beab530619aba877015dd48d509bc62b

Summary:
`unsigned int` is a more typical definition of the mode_t type on Linux systems, which is what this is trying to emulate.

Also guard by checking that HAVE_MODE_T isn't already define to allow clients to suppress its definition in cases where other client-used libraries (e.g. wxWindows) have their own definition which may conflict.
Pull Request resolved: https://github.com/facebook/folly/pull/1335

Reviewed By: yfeldblum

Differential Revision: D20408879

Pulled By: scramsby

fbshipit-source-id: 511484f6513501bf595ccb9cdfb893c9d5761320

Summary:
Compiling with gcc 10.0.1 and -std=gnu++2a, we have the following errors:
```
folly/FBString.h:1013:33: error: no type named 'reference' in 'class std::allocator<char>'
 1013 |   typedef typename A::reference reference;
      |                                 ^~~~~~~~~
folly/FBString.h:1014:39: error: no type named 'const_reference' in 'class std::allocator<char>'
 1014 |   typedef typename A::const_reference const_reference;
```
This is due to the fact many members in `std::allocator` have been remove in C++20: https://en.cppreference.com/w/cpp/memory/allocator

We also have this one due to the new way C++ resolves the comparison operators:
```
folly/dynamic-inl.h:854:20: error: ambiguous overload for 'operator!=' (operand types are 'folly::dynamic::const_item_iterator' and 'folly::dynamic::const_item_iterator')
  854 |   return find(key) != items().end() ? 1u : 0u;
      |          ~~~~~~~~~ ^~ ~~~~~~~~~~~~~
      |              |                   |
      |              |                   folly::dynamic::const_item_iterator
      |              folly::dynamic::const_item_iterator
In file included from folly/dynamic-inl.h:25,
                 from folly/dynamic.h:796,
                 from folly/dynamic.cpp:17:
folly/detail/Iterators.h:80:8: note: candidate: 'bool folly::detail::IteratorFacade<D, V, Tag>::operator==(const D&) const [with D = folly::dynamic::const_item_iterator; V = const std::pair<const folly::dynamic, folly::dynamic>; Tag = std::f
orward_iterator_tag]' (reversed)
   80 |   bool operator==(D const& rhs) const {
      |        ^~~~~~~~
folly/detail/Iterators.h:98:3: note: candidate: 'typename std::enable_if<std::is_convertible<D, D2>::value, bool>::type folly::detail::IteratorFacade<D, V, Tag>::operator==(const D2&) const [with D2 = folly::dynamic::const_item_iterator; D =
 folly::dynamic::const_item_iterator; V = const std::pair<const folly::dynamic, folly::dynamic>; Tag = std::forward_iterator_tag; typename std::enable_if<std::is_convertible<D, D2>::value, bool>::type = bool]' (reversed)
   98 |   operator==(D2 const& rhs) const {
      |   ^~~~~~~~
folly/detail/Iterators.h:84:8: note: candidate: 'bool folly::detail::IteratorFacade<D, V, Tag>::operator!=(const D&) const [with D = folly::dynamic::const_item_iterator; V = const std::pair<const folly::dynamic, folly::dynamic>; Tag = std::f
orward_iterator_tag]'
   84 |   bool operator!=(D const& rhs) const {
      |        ^~~~~~~~
folly/detail/Iterators.h:103:8: note: candidate: 'bool folly::detail::IteratorFacade<D, V, Tag>::operator!=(const D2&) const [with D2 = folly::dynamic::const_item_iterator; D = folly::dynamic::const_item_iterator; V = const std::pair<const f
olly::dynamic, folly::dynamic>; Tag = std::forward_iterator_tag]'
  103 |   bool operator!=(D2 const& rhs) const {
      |        ^~~~~~~~
```
Pull Request resolved: https://github.com/facebook/folly/pull/1329

Reviewed By: ot, igorsugak

Differential Revision: D20443631

Pulled By: yfeldblum

fbshipit-source-id: 03e8210a64a3eeaefb6f14afaddf45be882e3ba6

Summary: Both operators use their own copy of the container (eg line 104), so mutating it should be ok

Reviewed By: ot

Differential Revision: D19170228

fbshipit-source-id: a53094bdbd3fb7b5028cf7ed4e0b073dd919b2d7

Summary:
[Folly] Add `#include <bit>` in `folly/lang/Bits.h` when that header, which is introduced in C++20, is available.

Fixes https://github.com/facebook/folly/issues/1333.
Closes https://github.com/facebook/folly/pull/1334.

Reviewed By: luciang, markisaa

Differential Revision: D20369239

fbshipit-source-id: fee8682c23107a1da17c35abf5a9e16bb5177cdd

Summary: When n = 1, `oneIn` is always true. This can be used to avoid generating a random number.

Reviewed By: yfeldblum

Differential Revision: D20267645

fbshipit-source-id: 0c0bde1e80389f11ffdb0ad0f0de053d47b9f760

Summary:
Next OpenNSA release with increased stack size (needed for FBOSS) is available.
Start linking with it.

Differential Revision: D20062997

fbshipit-source-id: 9938270c322087ac3990861aa1ddd3b9ea1148ac

Summary: Add UDP GRO support

Reviewed By: mjoras

Differential Revision: D20347326

fbshipit-source-id: be3c31f070c4f2c1ef84f9e2df60f49a5fcabd93

Summary: Move `toStdString` to `FBString.h` because it's fbstring-related and remove the dependency between `String.h` and `FBString.h`. This is possible because the only other use of fbstring in `String.h` is removed in previous diff.

Reviewed By: yfeldblum

Differential Revision: D20195591

fbshipit-source-id: b5ff7c918669e063e24bf91155a2496f82d7e975

Summary: Add ThreadWheelTimekeeperHighRes class

Reviewed By: LeeHowes

Differential Revision: D20355093

fbshipit-source-id: b76563a3706d7732b490a88096fed484954820e5

Summary: It looks like that test file was deleted, but it was still referenced in a CMakeLists.txt file.

Reviewed By: yfeldblum, Gownta

Differential Revision: D20365343

fbshipit-source-id: 40792bb9c526e1aef48062b0e560646bdcf201b8

Summary:
Add support for onClear() callback function to RequestData. The callback is to be executed on the last clearing of RequestData. This typically happens upon the destruction of the last RequestContext that contains the RequestData or due to explicit calls to RequestContext::clearContextData that remove the RequestData from the RequestContext.

The onClear() callback is executed exactly once. If there are no calls to clearContextData, then onClear is executed upon the destruction of the last RequestContext that refers to the RequestData. If there are calls to clearContextData, then onClear is executed upon the removal of the last reference to the RequestData from a RequestContext.

RequestData::hasCallback() applies only to onSet() and onUnset() which may be called multiple times, whereas onClear() is called exactly once.

If a class derived from RequestData overrides onClear and either or both of onSet and onUnset, then care must be taken that the callbacks are mutually safe, as it is possible for the execution of onClear to be concurrent with executions of onSet and onUnset.

Motivation: Some uses of RequestContext::clearContextData expect the immediate destruction of associated RequestData. The hazard pointer-based implementation of RequestContext guarantees only that all associated RequestData is destroyed before the completion of the destructor of the RequestContext. This callback provides users of RequestContext more control of the timing of executing actions related to clearing the data. The addition of this capability is intended to provide a tool to eliminate differences in timing of executing actions between the two implementations of RequestContext (hazard pointer-based vs. read lock-based).

Also, fixes a minor bug in request_context_test, where the key "test2" was used in two tests (setIfAbsentTest and deadlockTest) without being cleared, which generated a warning when the tests were run in the same process.

Reviewed By: davidtgoldblatt

Differential Revision: D20332008

fbshipit-source-id: c9cefffb28c8da098e97f851f31d29a1bf704061

Summary:
Clean the sigar build dependency completely under:
- fbcode/fbzmq/public_tld/build/...
- fbcode/openr/public_tld/build/...

Delete files:
- fbcode/opensource/fbcode_builder/manifests/sigar
- fbcode/opensource/fbcode_builder/specs/sigar.py

Reviewed By: steven1327

Differential Revision: D20376067

fbshipit-source-id: 3321a14df2551525acee605028ef06a04cda7c6a

Summary: This is mainly used for logging, and we can elide an unnecessary copy in some cases.

Reviewed By: mingtaoy

Differential Revision: D20402430

fbshipit-source-id: 79b73792a69cf2817ffb88b07d9973139c3c67bb

Summary: Split WTCallback cod

Reviewed By: LeeHowes

Differential Revision: D20355082

fbshipit-source-id: 9ead4905cafeef27a9e2956fc50ebd59098cb80e

Summary:
Use decltype(event::ev_fd) instead of #ifdef

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum, kevin-vigor

Differential Revision: D18525100

fbshipit-source-id: 7cef32def7b40c71b2298f9dc354fbe63607fb8e

Summary:
As written in the documentation, {fmt} should be built alongside folly. This is not possible in my case. My usecase is to provide some kind of small distribution of shared libraries that can be installed on any systems. Hence I really need to have libfmt treated as a normal shared lib.

Moreover, libfmt can be consumed on our side as a normal library outside on cmake. We do not provide the cmake config file which are strongly dependent on the system on which libfmt is installed.

My proposal is to first look for the fmt-config.cmake as it is now but in case of cmake support is not provided by system, we fall back to a normal library lookup.
Pull Request resolved: https://github.com/facebook/folly/pull/1328

Reviewed By: simpkins

Differential Revision: D20312046

Pulled By: yfeldblum

fbshipit-source-id: 2d6b4917b37a8ed1d553600599702259db22c212