Add DCHECKs for checking that underlying IOBuf wasn't modified

Summary: Appending/prepending to IOBuf while iterating over it with Cursor is unsafe. This diff adds DCHECKs to catch such cases.

Reviewed By: yfeldblum

Differential Revision: D6735060

fbshipit-source-id: 7799facc52c53fabd83756ecb26a18c4ebd69677

Loop Time

Summary:
Only do the exponential loop smoothing once every 10ms.
If we need it before then, do it linearly.

Also, remove one of the now()s by only calling it once.

Reviewed By: bmaurer, yfeldblum

Differential Revision: D6690047

fbshipit-source-id: 8267c01064aabc17cb8e86eb888e6120c99a129f

Properly handle appending to the tail of the chain

Summary: Currently appending to the tail of the chain would cause the cursor advancing to the beginning of the chain, which is not correct, instead we should advance to the tail.

Reviewed By: yfeldblum

Differential Revision: D6734999

fbshipit-source-id: b8b2585e0475b656f7b6bf4ed39686e2ccb2e432

add tryCreateNetwork()

Summary: Add non-throwing version of createNetwork(), and rework existing code to throw exceptions based on error codes returned by non-throwing version.

Reviewed By: yfeldblum

Differential Revision: D6705425

fbshipit-source-id: 268ff64c36e7cceeea3463248d18b7b2cb81390e

Fix Build: folly/synchronization/test/ParkingLotBenchmark.cpp (sign-compare, unused-variable)

Summary: [Folly] Fix Build: `folly/synchronization/test/ParkingLotBenchmark.cpp` (`sign-compare`, `unused-variable`).

Reviewed By: djwatson

Differential Revision: D6733586

fbshipit-source-id: 04b82110e8e0b655e6b3994dbca3bd0b4bd57eef

cmake: fix path to FindGLog.cmake

Summary:
The cmake files refer to this package as "FindGLog", but the file name on disk
incorrectly had the 'L' lower cased.  This worked on case-insensitive file
systems, but caused cmake to fail when used on a case-sensitive file system.

This diff fixes the file name to match the name used in the cmake files.  This
is also more consistent with the existing "FindGFlags" and "FindGMock"
packages.

Reviewed By: yfeldblum

Differential Revision: D6710439

fbshipit-source-id: 19f6824ef6793e505b5a0080c0fefe0b145a41c3

Revert D6725091: [Folly] Use thread-local in RequestContext::getStaticContext

Summary:
This reverts commit 9979f39677284b1051cb109b461097495d77ca17

bypass-lint

An infra SEV is better than not reverting this diff.
If you copy this password, see you in SEV Review!
cause_a_sev_many_files

Differential Revision: D6725091

fbshipit-source-id: f1e3c80c869aa47684f5fbe79528e68174dee568

parkinglot benchmark

Summary: Add benchmark vs. futex

Reviewed By: yfeldblum

Differential Revision: D6639280

fbshipit-source-id: 9735444a7f48011f31603159561675d472cc4411

define SKIP_IF

Summary:
Finding ourselves writing too many identical "if (expr) SKIP << ..." statements,
this change factors out/encapsulates the functionality.

Reviewed By: yfeldblum

Differential Revision: D6727531

fbshipit-source-id: 703abcd5d8c30a6ebab94327a12da4f2d1f7ff74

Use thread-local in RequestContext::getStaticContext

Summary:
[Folly] Use thread-local in `RequestContext::getStaticContext`.

`folly::SingletonThreadLocal` uses `folly::ThreadLocal`. However, `static FOLLY_TLS` (`static __thread`) is always faster than `folly::ThreadLocal` for thread-local singletons for which iteration is not required.

Reviewed By: djwatson

Differential Revision: D6725091

fbshipit-source-id: 9979f39677284b1051cb109b461097495d77ca17

Fix missing WaitOptions symbol in autotools build

Summary:
[Folly] Fix missing `WaitOptions` symbol in autotools build.

Closes #736.

Reviewed By: spalamarchuk

Differential Revision: D6724950

fbshipit-source-id: 54ac0d1a743aa38fe1a7a2bdce585fced18c5a44

Track absolute position of the cursor

Summary:
Start tracking the position of the cursor from the head of IOBuf chain. This comes at almost no cost (one arithmetic operation on IOBuf advance).

The main use case for this cursor is Thrift deserialization code. It allows us to stop accumulating `xfer` on every single byte/field/element write and instead get it from Cursor in the end (when we're exiting Thrift code).
This allows achieving ~10% better performance of deserialization.

Reviewed By: yfeldblum

Differential Revision: D6646813

fbshipit-source-id: 8f796854a24a411698e96afe037695e816813022

Improve fast path of Cursor

Summary:
This change simplifies the fastpath by reducing it to bare minimum (i.e. check length, load data) and removes indirection to IOBuf.
Additionally it adds `skipNoAdvance` method to have 1-instruction skip.

Disassembly of `read<signed char>` is over 35 instructions (just hot path). With this change it's doesn to 8.
Disassembly after:
  Dump of assembler code for function folly::io::detail::CursorBase<folly::io::Cursor, folly::IOBuf const>::read<unsigned char>():
     0x000000000041f0f0 <+0>:     mov    0x18(%rdi),%rax
     0x000000000041f0f4 <+4>:     lea    0x1(%rax),%rcx
     0x000000000041f0f8 <+8>:     cmp    0x10(%rdi),%rcx
     0x000000000041f0fc <+12>:    ja     0x41f105 <folly::io::detail::CursorBase<folly::io::Cursor, folly::IOBuf const>::read<unsigned char>()+21>
     0x000000000041f0fe <+14>:    mov    (%rax),%al
     0x000000000041f100 <+16>:    mov    %rcx,0x18(%rdi)
     0x000000000041f104 <+20>:    retq
     0x000000000041f105 <+21>:    jmpq   0x41f110 <folly::io::detail::CursorBase<folly::io::Cursor, folly::IOBuf const>::readSlow<unsigned char>()>

With this diff Thrift deserialization becomes ~20% faster (with prod workloads).

Thrift benchmark:
Before:
  ============================================================================
  thrift/lib/cpp2/test/ProtocolBench.cpp          relative  time/iter  iters/s
  ============================================================================
  BinaryProtocol_read_Empty                                   12.98ns   77.03M
  BinaryProtocol_read_SmallInt                                20.94ns   47.76M
  BinaryProtocol_read_BigInt                                  20.86ns   47.93M
  BinaryProtocol_read_SmallString                             34.64ns   28.86M
  BinaryProtocol_read_BigString                              185.53ns    5.39M
  BinaryProtocol_read_BigBinary                               67.34ns   14.85M
  BinaryProtocol_read_LargeBinary                             62.23ns   16.07M
  BinaryProtocol_read_Mixed                                   58.74ns   17.03M
  BinaryProtocol_read_SmallListInt                            89.99ns   11.11M
  BinaryProtocol_read_BigListInt                              39.92us   25.05K
  BinaryProtocol_read_BigListMixed                           616.20us    1.62K
  BinaryProtocol_read_LargeListMixed                          83.49ms    11.98
  CompactProtocol_read_Empty                                  11.28ns   88.67M
  CompactProtocol_read_SmallInt                               19.15ns   52.22M
  CompactProtocol_read_BigInt                                 26.14ns   38.25M
  CompactProtocol_read_SmallString                            31.04ns   32.22M
  CompactProtocol_read_BigString                             184.55ns    5.42M
  CompactProtocol_read_BigBinary                              69.73ns   14.34M
  CompactProtocol_read_LargeBinary                            64.39ns   15.53M
  CompactProtocol_read_Mixed                                  58.73ns   17.03M
  CompactProtocol_read_SmallListInt                           76.50ns   13.07M
  CompactProtocol_read_BigListInt                             25.93us   38.56K
  CompactProtocol_read_BigListMixed                          623.15us    1.60K
  CompactProtocol_read_LargeListMixed                         80.57ms    12.41
  ============================================================================

After:
  ============================================================================
  thrift/lib/cpp2/test/ProtocolBench.cpp          relative  time/iter  iters/s
  ============================================================================
  BinaryProtocol_read_Empty                                   10.40ns   96.17M
  BinaryProtocol_read_SmallInt                                15.14ns   66.03M
  BinaryProtocol_read_BigInt                                  15.19ns   65.84M
  BinaryProtocol_read_SmallString                             25.19ns   39.70M
  BinaryProtocol_read_BigString                              172.85ns    5.79M
  BinaryProtocol_read_BigBinary                               56.88ns   17.58M
  BinaryProtocol_read_LargeBinary                             56.77ns   17.61M
  BinaryProtocol_read_Mixed                                   43.98ns   22.74M
  BinaryProtocol_read_SmallListInt                            58.19ns   17.19M
  BinaryProtocol_read_BigListInt                              19.75us   50.63K
  BinaryProtocol_read_BigListMixed                           440.20us    2.27K
  BinaryProtocol_read_LargeListMixed                          56.94ms    17.56
  CompactProtocol_read_Empty                                   9.35ns  106.93M
  CompactProtocol_read_SmallInt                               13.07ns   76.49M
  CompactProtocol_read_BigInt                                 18.23ns   54.87M
  CompactProtocol_read_SmallString                            25.61ns   39.05M
  CompactProtocol_read_BigString                             174.46ns    5.73M
  CompactProtocol_read_BigBinary                              59.77ns   16.73M
  CompactProtocol_read_LargeBinary                            60.81ns   16.44M
  CompactProtocol_read_Mixed                                  42.70ns   23.42M
  CompactProtocol_read_SmallListInt                           66.89ns   14.95M
  CompactProtocol_read_BigListInt                             25.08us   39.87K
  CompactProtocol_read_BigListMixed                          427.93us    2.34K
  CompactProtocol_read_LargeListMixed                         56.11ms    17.82
  ============================================================================

Reviewed By: yfeldblum

Differential Revision: D6635325

fbshipit-source-id: 393fc1005689042977c03f37f5a898ebe7814d44

allow command to accept "--" separator

Summary:
Currently NestedCommandLineApp does not support `--` to indicate that the following arguments should be parsed as arguments, not nested commands or options.
This diff fix that by whitelisting any argument given after "--"

Reviewed By: yfeldblum

Differential Revision: D6721144

fbshipit-source-id: 38a850b6ea803dc758c5fe65a21575e5faeac35b

Fix copyright lines

Summary: [Folly] Fix copyright lines based on file histories.

Reviewed By: spalamarchuk

Differential Revision: D6720312

fbshipit-source-id: c70a667a1977e70e2d4451ea624f96163982f681

Convert newlines in folly/portability/PThread.cpp

Summary:
[Folly] Convert newlines in `folly/portability/PThread.cpp`.

```
dos2unix folly/portability/PThread.cpp
```

Reviewed By: meyering

Differential Revision: D6720343

fbshipit-source-id: b92122b4a7012d7f8d73d293af51b4fcc868c582

Add Tearable, for concurrently-modified non-atomic objects.

Summary:
This adds the Tearable class template, which holds storage for an
arbitrarily-sized object that can be concurrently read or written without any
external synchronization.

Reviewed By: yfeldblum, djwatson

Differential Revision: D6422334

fbshipit-source-id: ee3853bbd393ac8e30dca6439c61606cc5495f92

Promote aligned_malloc and aligned_free

Summary:
[Folly] Promote `aligned_malloc` and `aligned_free` from `namespace folly::detail` to `namespace folly`.

And move them from `folly/portability/Memory.h` to `folly/Memory.h`.

Differential Revision: D6153394

fbshipit-source-id: eef314d2bc171910ea3c8403da9e9e1d1858ce15

cmake: remove DOS-style line endings

Summary:
A number of the files in CMake/ had inconsistent line-endings.  This updates
files using DOS-style CRLF line endings to just use CR instead.  On Windows,
git is capable of automatically changing CR to CRLF when checking out the
repository working directory.

Reviewed By: meyering

Differential Revision: D6714717

fbshipit-source-id: 82adccf4e522d38fd1cb420869f62e52dbd6c5f1

cmake: add checks to generate folly-config.h correctly

Summary:
Add proper checks to detect and set the values in folly-config.h correctly.
Previously the code simply hard-coded values that were appropriate for Windows.

This does not yet define all of the settings produced by the autoconf build,
but it lets the CMake-based build largely succeed on Linux systems.

Reviewed By: meyering

Differential Revision: D6710437

fbshipit-source-id: 80490080ee6322995b740ac2a15181d220c6874a

cmake: set compiler flags for non-Windows platforms

Summary:
Update CMakeLists.txt to check the current platform, and to set compiler flags
correctly.  It now uses flags for Microsoft Visual Studio on Windows, and flags
for gcc or clang on all other platforms.  Previously it unconditionally used
MSVC flags.

Reviewed By: meyering

Differential Revision: D6710435

fbshipit-source-id: dbae3097bcadf1ee4a25879dd7770603387c0e4d

cmake: support using a separate build directory

Summary:
Fix rules in the CMakeLists.txt file that generate source files to first create
their output directory if necessary.  This allows the build to succeed when
building with a separate build output directory, rather than placing build
artifacts in the source tree itself.

Reviewed By: meyering

Differential Revision: D6710436

fbshipit-source-id: 786a65a37a70833e7e4a5affe4df292626dbb591

correctly handle APIs that accept Poly<T&> as an argument

Summary: Multi-dispatch in Poly was handled by treating arguments of type Poly<I&> as special, unwrapping them. That's a problem if the underlying API actually wants the Poly<I&> unmolested.

Reviewed By: yfeldblum

Differential Revision: D6713975

fbshipit-source-id: 18a90fa701fab14c3d3d46c247efe09ea5903b11

Register singleton's destruction using std::atexit

Summary:
scheduleDestroyInstances function is called from createInstance function when
new instance of specific singleton type is created thus marking a point in
static objects order  when all singltons will be destructed.
This does not work well for situations when singleton is loaded as part of
python extension which is a shared object. In this case static objects of this
shared object would be constructed first and singleton from this extension will
be created after that. Since destruction order is reversed and all singletons
will be destructed together, static objects of python extension will be
destroyed before singleton from this extension. Which leads to heap-after-free
ASAN exceptions.
In other words, lifetime of all folly singletons is aligned to the lifetime of the
first created folly singleton.
Using std::atexit to register singleton's destruction from singleton
constructor will align  lifetime of singletons to the most recent singleton
which matters for python extensions and does not matter for other use cases.

Reviewed By: andriigrynenko

Differential Revision: D6705644

fbshipit-source-id: 5c933886ceae649e3c75f8e7e7936d5a7ed04539

Spell uintptr_t properly in static_assert in `getStackTrace()`

Summary:
While here, pet the linter with respect to the warning around the indentation with the comment containing the licensing tort.

Signed-off-by: Enji Cooper <yaneurabeya@gmail.com>
Reviewed By: yfeldblum

Differential Revision: D6710314

fbshipit-source-id: fc0b971e6300af9c63a690c54c08fc70e0313b70

Unsafe pre-sorted construction for sorted-vector containers

Summary:
[Folly] Unsafe pre-sorted construction for sorted-vector containers.

If the backing container type can be constructed directly in sorted order or can be determined in advance to be in sorted order, then a special constructor can help code take advantage of this condition by avoiding an extra invocation of `std::sort`.

Reviewed By: spalamarchuk

Differential Revision: D6708379

fbshipit-source-id: 25d886b0814dc9230c6046ed1e7f199fac47754e

cmake: fix error message on non-Windows platform

Summary:
Building folly with cmake is only supported on Windows for now.  This fixes
cmake on non-Windows platforms to fail with a helpful message telling people to
use autoconf.  This message was in place before, but was after an MSVC version
check preventing it from appearing.

Reviewed By: meyering

Differential Revision: D6707328

fbshipit-source-id: a28a07ab0da41d605b11d93bba40f33520c5f57e

MemoryIdler::futexWaitUntil

Summary:
[Folly] `MemoryIdler::futexWaitUntil`.

Adds `MemoryIdler::futexWaitUntil` that works like `Futex::futexWaitUntil`, in a similar way that `MemoryIdler::futexWait` works like `Futex::futexWait`.

Removes the ability to customize the idle-timeout clock for `MemoryIdler::futexWait` as a side-effect; the idle-timeout is now a pure duration. Now, the clock used with the idle-timeout is the same as the normal deadline clock, so the idle-timeout clock can be set for `MemoryIdler::futexWaitUntil` by providing a deadline with that clock type. This normally would not matter, but it affects the unit-tests.

Reviewed By: djwatson

Differential Revision: D6681679

fbshipit-source-id: e3cf6e71d7530c5877a834b318b423eb91f71eb9

Relax stop_ memory order

Summary: stop_ can be relaxed everywhere, it implies only an asynchronous signal, not any sort of memory barrier.

Reviewed By: davidtgoldblatt

Differential Revision: D6690079

fbshipit-source-id: 6f193204e1619f9a8adf81db2d46d05954bfbf85

Cut the ScopeGuard alias now that we have auto

Summary:
[Folly] Cut the `ScopeGuard` alias now that we have `auto`.

This form works because of hidden lifetime extension:
```lang=c++
folly::ScopeGuard guard = folly::makeGuard([] { /*...*/ });
//  ...
//  guard falls out of scope
```
But this form would not work correctly:
```lang=c++
folly::ScopeGuard guard = folly::makeGuard([] { /*...*/ });
std::async(std::launch::async, [guard = std::move(guard)] {});
```
Because `folly::ScopeGuard` is an rvalue-reference-to-base.
We have `auto`, so just remove `folly::ScopeGuard`. This form works correctly:
```lang=c++
auto guard = folly::makeGuard([] { /*...*/ });
std::async(std::launch::async, [guard = std::move(guard)] {});
```

Reviewed By: igorsugak

Differential Revision: D6690070

fbshipit-source-id: 54e32b300d36fce4eb95a59f1828819afe312ec0

Move ScopeGuardImpl and ScopeGuardImplBase into the detail namespace

Summary:
[Folly] Move `ScopeGuardImpl` and `ScopeGuardImplBase` into the `detail` namespace.

Let them be marked as private implementation details.

Reviewed By: andrewjcg

Differential Revision: D6665317

fbshipit-source-id: 03e8fee6a16338395ec92c582613b053bd9f74ec

Stop using ScopeGuardImpl in DynamicParser

Summary:
[Folly] Stop using `ScopeGuardImpl` in `DynamicParser`.

`ScopeGuardImpl` is an impl type that should not be treated as public.

Reviewed By: igorsugak

Differential Revision: D6689835

fbshipit-source-id: aea6c985e40887594c0aeb0c0948fa77c149a89b

folly::Init, RAII variant of folly::init

Summary:
[Folly] `folly::Init`, RAII variant of `folly::init`.

Use it in `main` used by unit-tests.

Reviewed By: ot

Differential Revision: D6566358

fbshipit-source-id: fb8e5a18fc43eb65e2cbeb070d97094bd413bb96

UnboundedQueue: Use hazptr_obj_batch

Summary: Manage retirement of removed segments using hazptr_obj_batch in order to reduce the chances of fragmenting related segments across thread local lists of retired objects of many threads, which could lead to unnecessarily high memory usage.

Reviewed By: djwatson

Differential Revision: D6686697

fbshipit-source-id: 0d786c0f9e0bac2c44183ed3da21619e1feb3d52

logging: fix build error when using gcc with -Wmissing-braces

Summary:
Since std::array is actually a struct containing an array it technically
requires double braces around its initializer.  The language allows eliding
these braces, and clang doesn't complain about only using a single brace, but
gcc does when using `-Wmissing-braces`.

Reviewed By: yfeldblum

Differential Revision: D6695289

fbshipit-source-id: 913fcfbea4164a02d001bd2344e340c0b6ee62aa

Let Futex import base-class ctors

Summary:
[Folly] Let `Futex` import base-class ctors.

Rather than needing to define ctors and inherit `boost::noncopyable`.

Reviewed By: WillerZ

Differential Revision: D6674054

fbshipit-source-id: 59e0a4815682b227346954fe47c6eda49e3ad62f

Add hazptr_obj_batch

Summary: Provide capability for custom batching retirement of objects, for example object that belong to the same data structure, to avoid the risk fragmenting related objects across thread local lists of retired objects of many threads, which could lead to unnecessarily high memory usage.

Reviewed By: djwatson

Differential Revision: D6686603

fbshipit-source-id: fadcade73e71170ef1bcec221c4da6f4ddeecff5

Tweak FutexResult comments

Summary: [Folly] Tweak `FutexResult` comments.

Reviewed By: nbronson

Differential Revision: D6673979

fbshipit-source-id: 1777311cd93d5a83432c4ebb48a8432a1c504ca9

Futex::futexWait returns FutexResult

Summary: [Folly] `Futex::futexWait` returns `FutexResult`.

Reviewed By: nbronson

Differential Revision: D6673871

fbshipit-source-id: 378c69d8362970e985da31e31d8e9b0179d2917f

Support for all clock types in Futex

Summary:
[Folly] Support for all clock types in `Futex`.

Only `system_clock` and `steady_clock` remain optimal as before, but at least let `Futex` work, even if non-optimally, for all clock types.

Reviewed By: nbronson

Differential Revision: D6673741

fbshipit-source-id: 0a0f778f61b71bea76e12b7fab478e33ce3bbaae

Use ptr-to-const in Futex

Summary: [Folly] Use ptr-to-`const` in `Futex`.

Reviewed By: igorsugak

Differential Revision: D6673723

fbshipit-source-id: b828c2284b40ec8166e823eca7725beccd330f87

Fix some copyright lines in folly/detail/ and folly/test/

Summary: [Folly] Fix some copyright lines in `folly/detail/` and `folly/test/`.

Differential Revision: D6673878

fbshipit-source-id: 6c060a974bb4d40d0f24a44ebddddf892805c65e

Baton support for wait-options

Summary: [Folly] Baton support for wait-options

Reviewed By: nbronson

Differential Revision: D6591168

fbshipit-source-id: beca8422ac0daa572fb43c371923a86f199999f9

Timed wait operations for spin-only Baton

Summary:
[Folly] Timed wait operations for spin-only `Baton`.

Enables `try_wait_for` and `try_wait_until` for `Baton</* MayBlock = */ false, /*...*/>`.

Reviewed By: nbronson

Differential Revision: D6672153

fbshipit-source-id: 95da07260b21c2b88b8f7bf81cbfcbe5f5099ac0

logging: include file name suffixes in XLOG() category names

Summary:
Update `getXlogCategoryNameForFile()` to keep the file name suffix (e.g., `.h`
or `.cpp`) in the category name.  Previously the code had stripped this out.
However it seems worth leaving it in:
- This makes it possible to independently control log levels for messages from
  the header file vs the cpp file.
- This makes the category name logic slightly easier to explain to users.

The documents I added in D6525997 already describe this new category name
selection behavior.  This change updates the code to match the documented
behavior.

Reviewed By: yfeldblum

Differential Revision: D6690464

fbshipit-source-id: 9af6b549d084bd900f788a08e9213e82579b664a

logging: add numbered INFO* log level values

Summary:
Define INFO0 through INFO9 levels for users that want to have finer-grained
control over info log messages.

This also renumbers the DBG log levels slightly so that there are exactly 1000
levels between each major log level step.  This renumbering change should not
affect any code behavior, since these level values are primarily used in memory
and aren't saved persistently anywhere.

Reviewed By: yfeldblum

Differential Revision: D6690466

fbshipit-source-id: acd499cff6830a1d1b579f295bd4b2bac93b5ada

logging: rename the `DEBUG` log level to `DBG`

Summary:
I ran into some open source projects that define `DEBUG` as a preprocessor
macro on the compiler command line.  (They effectively defined it as the
opposite of `NDEBUG`.)  Doing some Google searches revealed that there are a
number of projects that appear to use this as a macro.

Therefore this diff renames the `DEBUG` log level enum value to `DBG` to avoid
potentially conflicting with projects that do use `DEBUG` as a macro name.

I did keep the behavior that `logLevelToString()` returns "DEBUG" for an input
of `LogLevel::DBG`.

Reviewed By: yfeldblum

Differential Revision: D6690465

fbshipit-source-id: 35bb1698afb45eb670e60c192f21390cbf09331d

Change the enumerate() example to bind the proxy by reference

Summary:
When compiling without optimizations binding the proxy by
reference is slightly faster (no differences in opt mode), so change
the documentation to recommend this syntax.

The proxy can still be bound by `auto`, `const auto`, and `const
auto&`, in all case behaving as expected and with no overhead in opt
mode. Added a test to make sure these all work.

Reviewed By: yfeldblum, luciang

Differential Revision: D6688958

fbshipit-source-id: 7c6b460a01708786bda7614546fa2e1667f27299

Improve performance of enumerate() with optimization disabled

Reviewed By: yfeldblum, WillerZ

Differential Revision: D6682606

fbshipit-source-id: 5a203a849e96d3020cf9ad2669451122954c2199

Fixing typo in sorted_vector_types.h

Summary:
title

Created from Diffusion's 'Open in Editor' feature.

(Note: this ignores all push blocking failures!)

Reviewed By: Sushisugre

Differential Revision: D6688367

fbshipit-source-id: 6e2f2d3fcb897fe78c1caef841515856b1f2bd42

Return if we handle any error messages to avoid unnecessarily calling recv/send

Summary: Return if we handle any error messages to avoid unnecessarily calling recv/send

Reviewed By: yfeldblum

Differential Revision: D6677314

fbshipit-source-id: 21f724bb2c92b954888ba97bf7820d72decd2775

use in futex

Summary: Use new ParkingLot API in futex.

Reviewed By: yfeldblum

Differential Revision: D6595853

fbshipit-source-id: 7024ac1d3e0c5958a651a3e33c1427038bbe7808

Add a check if max atomic_shared_ptrs is reached.

Summary:
Batching reference counts reduces the maximum number of atomic_shared_ptrs
available to the system (and also shared_ptrs).

Add a check, test, and some comments about it.

Reviewed By: yfeldblum

Differential Revision: D5916291

fbshipit-source-id: 0bbf7b43284d94a304201219883c82b3654c1585

UnboundedBlockingQueue: Adjust segment size

Summary: Adjust the segment size of the `UnboundedQueue` to 64 instead of 256, a size more suitable for CPUThreadPoolExecutor::CPUTask elements.

Reviewed By: djwatson

Differential Revision: D6665918

fbshipit-source-id: c34c4fa936ee5c6d6a3dd4489129c936369f3980

give all folly exception types default visibility

Summary: This makes sure that whether folly is statically or dynamically linked, all folly exception types will have exactly one definition, and one set of type information.

Reviewed By: mzlee

Differential Revision: D6671431

fbshipit-source-id: 1c06826a05f87cbf9af747c9abdb5f524744d054

Update cpuid test to expect failure on non intel cpu

Summary: Found that testing would fail on aarch64 since mmx is an Intel thing.  Changed it to just check for x64.

Reviewed By: yfeldblum

Differential Revision: D6670050

fbshipit-source-id: 6ce4b45bb5ef02d65305636d6ac28be7631ddf1b

test that _sp includes nul bytes

Summary:
D6617812 wants to build a StringPiece from a literal with an
embedded nul. Add a test to verify that _sp is suitable for this use
case.

Reviewed By: yfeldblum

Differential Revision: D6651024

fbshipit-source-id: be4fb875762829fdb61c57fa72954fef286e9df0

Use local error buffer in readStoreFromBuffer

Summary: ERR_error_string will use a static buffer if none is provided.  This is unsafe in threaded envs when we build a string out of it later.  Switch this to use ERR_error_string_n

Reviewed By: yfeldblum, knekritz

Differential Revision: D6664958

fbshipit-source-id: 2071347373ac61ebc28296fa66845cd718172b5e

Remove gcc-v4.7 support from MemoryIdler

Summary:
[Folly] Remove gcc-v4.7 support from `MemoryIdler`.

As of gcc-v4.8, `std::is_trivial<std::chrono::duration<Rep, Period>>::value` holds. We no longer need any extra support.

Reviewed By: meyering

Differential Revision: D6673517

fbshipit-source-id: f28b2d126f113547ebf36c85f9fa37a5d944d65b

Terminal comma for FutexResult enumerators

Summary: [Folly] Terminal comma for `FutexResult` enumerators. Style nit.

Reviewed By: meyering

Differential Revision: D6673523

fbshipit-source-id: abf9f4d3e99bf9a6d3042a49252b1b1190e69b9f

Use auto for scope-guard locals v.s. folly::ScopeGuard

Summary: Use `auto` for scope-guard locals v.s. `folly::ScopeGuard`.

Reviewed By: igorsugak, meyering

Differential Revision: D6664915

fbshipit-source-id: ea239b712f3f9dc7ef81105aaf82f4b36bc07db5

give EventBase a non-explicit default constructor

Summary: Default constructors are strange and often unexpected. Refactor.

Reviewed By: yfeldblum

Differential Revision: D6667480

fbshipit-source-id: 24c456c46c846c61e28f1a88806d7c36d9192493

Add threshold for thread local retired objects

Summary: Change the threshold for pushing privately held retired object to the domain to a moderate constant instead of using the threshold for bulk reclamation which is too high for this purpose.

Reviewed By: djwatson

Differential Revision: D6665904

fbshipit-source-id: 0b090884843b0296a93af7994f7183f41c00000e

Synchronized::exchange

Summary:
[Folly] `Synchronized::exchange`, for assigning a new value and returning the old value.

(Note: this ignores all push blocking failures!)

Differential Revision: D6653482

fbshipit-source-id: 68f4bd330bc2cf37bb92aff98b8ce3221334112e

Fix copyright lines in folly/synchronization/Baton.h

Summary: [Folly] Fix copyright lines in `folly/synchronization/Baton.h`.

Reviewed By: meyering

Differential Revision: D6665595

fbshipit-source-id: 84aa0c475f01c858d543a047103437c083b3a4ed

Clarify folly::ssl::init documentation

Summary: Adds wording indicating that it is safe to call this function multiple times.

Reviewed By: yfeldblum

Differential Revision: D6625530

fbshipit-source-id: 2305f7b8e3451a6663003d23230b22c6f65a3729

Cut glog include from folly/synchronization/RWSpinLock.h

Summary: [Folly] Cut `glog` include from `folly/synchronization/RWSpinLock.h`.

Reviewed By: meyering

Differential Revision: D6659300

fbshipit-source-id: 0f1b79d98be0656694f57667252a16acd54e2414

Move folly/RWSpinLock.h to folly/synchronization/

Summary: [Folly] Move `folly/RWSpinLock.h` to `folly/synchronization/`.

Reviewed By: elsteveogrande

Differential Revision: D6659265

fbshipit-source-id: 307723e22f42ceb104f26657aed8b34f7e183afb

Extract WaitOptions

Summary:
[Folly] Extract `WaitOptions` from `SaturatingSemaphore`.

This type may prove useful in the future for a variety of similar cases, and so does not need to be locked up inside `SaturatingSemaphore`.

Additionally:
* Extract and redraft a comment from `Baton`.
* Rename `pre_block` to `spin_max`.

Reviewed By: djwatson, aary

Differential Revision: D6632875

fbshipit-source-id: 6b7faeeb6e1ac2011a037c2b560def0ee2e9f3d4

Move folly/BitIterator.h to folly/container/

Summary: [Folly] Move `folly/BitIterator.h` to `folly/container/`.

Reviewed By: djwatson

Differential Revision: D6648357

fbshipit-source-id: 5617e3210f58435fcbf3ef07fa745da47dbce475

Move InPlaceConstruction test in folly/test/SynchronizedTest.cpp

Summary: [Folly] Move `InPlaceConstruction` test in `folly/test/SynchronizedTest.cpp`.

Differential Revision: D6653481

fbshipit-source-id: f0eadfd6c2f41e9f597a666d01e40d5553447c70

Fix copyright lines for folly/Synchronized.h

Summary: [Folly] Fix copyright lines for `folly/Synchronized.h`.

Reviewed By: meyering

Differential Revision: D6664326

fbshipit-source-id: 71a0fc17358e41dfc751b8bcb0736c288975a4a0

Add utility to create stores

Summary: Add methods to create a X509StoreUniquePtr from a ca file or buffer.

Reviewed By: yfeldblum

Differential Revision: D6662538

fbshipit-source-id: 646f61596f2787756b2fa5998a43f36d75a91d90

Make FOLLY_HAS_COROUTINES dependent on header

Summary:
This breaks while building on aarch64 each time because the headers aren't
in the repo. I did a quick grep and I don't see anything in folly that
uses OptionalAwaitable or OptionalPromise so perhaps it's possible to
remove instead, can do that if preferred.  Depends on D6611609 to complete
build of tests cleanly.

Reviewed By: yfeldblum

Differential Revision: D6643759

fbshipit-source-id: f480d50383f85fbe905daaad74198b6557609347

Avoid allocs in dtors in futures collect

Summary:
[Folly] Avoid allocs in dtors in futures `collect`.

`CollectContext`, a detail helper type, allocates storage for a results vector in its dtor. This is an awkward situation and should be avoided.

Reviewed By: ericniebler

Differential Revision: D6649299

fbshipit-source-id: 87746fcc78fa080f63505d7bb864aca6c4a3d7cb

Fix to build SharedMutexTest on aarch64

Summary:
While trying to build folly on aarch64 found that the SharedMutexTest
wouldn't build because it uses RWTicketSpinLock which was only available
on x86 platforms.  Updated to allow build on aarch64 after suggestion by Orvid

Reviewed By: yfeldblum

Differential Revision: D6611609

fbshipit-source-id: 8ec477cdedac0f0a705608bbac42dd63b3efb919

Make consistent set of get and getTry methods on SemiFuture.

Summary: Complete set of get and getVia methods including addition of a result operation on FutureBase that provides functionality of the old getTry on Future by returning a Try by reference.

Reviewed By: yfeldblum

Differential Revision: D6640056

fbshipit-source-id: 3ac01f7bc4b128e641f08d9a99280a18ffce82f9

Remove SingletonVault C bindings

Summary: [Folly] Remove `SingletonVault` C bindings. They are not generally needed.

Reviewed By: spalamarchuk

Differential Revision: D6632104

fbshipit-source-id: 3aecb35277bc76a2171487404d6994a5ea296afc

Use member-invoke traits in LockTraits

Summary:
[Folly] Use member-invoke traits in `LockTraits`.

V.s. spelling out the SFINAE manually.

Reviewed By: Orvid

Differential Revision: D6637380

fbshipit-source-id: 212e0cc5e54503b31e458b6bda93b2a3b24e6c59

invoke and member-invoke tweaks

Summary:
[Folly] `invoke` and member-`invoke` tweaks.

* Direct `static_cast` v.s. `std::forward` is okay.
* Implement member-`invoke` in terms of `invoke` and extract most of it to a helper type, minimizing the code directly generated by the preprocessor.

Reviewed By: spalamarchuk

Differential Revision: D6644119

fbshipit-source-id: e58a83d7ff2dd71b0377d864ef089c34e0239c8d

Add ColdClassTest.cpp to oss builds

Summary: [Folly] Add `ColdClassTest.cpp` to oss builds.

Reviewed By: spalamarchuk

Differential Revision: D6648831

fbshipit-source-id: f8d8a727d63e4e8b83391db454de990027f1bad4

Fix copyright lines for Bits.h and move BitsBenchmark.cpp

Summary: [Folly] Fix copyright lines for `Bits.h` and move `BitsBenchmark.cpp`.

Reviewed By: spalamarchuk

Differential Revision: D6648828

fbshipit-source-id: 5eed558ac2d47a1497d64173bc84a4ca27d79764

Fix some copyright lines in folly/

Summary:
[Folly] Fix some copyright lines in `folly/`.

(Note: this ignores all push blocking failures!)

Reviewed By: Orvid

Differential Revision: D6648215

fbshipit-source-id: 6fc446028ff79aa44116424e86ad454077717f8e

Fix some copyright lines in folly/lang/

Summary:
[Folly] Fix some copyright lines in `folly/lang/`.

(Note: this ignores all push blocking failures!)

Reviewed By: Orvid

Differential Revision: D6648214

fbshipit-source-id: fa2afdb8369252b74b914622ad39f7f27261d2c1

Fix some copyright lines in folly/experimental/symbolizer/

Summary:
[Folly] Fix some copyright lines in `folly/experimental/symbolizer/`.

(Note: this ignores all push blocking failures!)

Reviewed By: Orvid

Differential Revision: D6648183

fbshipit-source-id: 36f9df5af91400a37dfa5ee2b209ffd47d5069df

constexpr_pow

Summary:
[Folly] `constexpr_pow`.

The power function. Initially, supports nonnegative integers only.

Reviewed By: spalamarchuk

Differential Revision: D6646376

fbshipit-source-id: 33a5a45f496b6f3be52d0cd7e3a5f2cd7edb3026

Give detail functions in ConstexprMath.h decorated names

Summary:
[Folly] Give detail functions in `ConstexprMath.h` decorated names.

So that other code also in `namespace folly::detail` which invokes the non-detail functions will result in ambiguity.

Reviewed By: spalamarchuk

Differential Revision: D6646313

fbshipit-source-id: 679e4cfe1c90f494acacef8b2a38a453db4d79d5

Shift monotonic_coarse_clock into Chrono.h and rename it to coarse_steady_clock

Summary: The rename is to bring it closer in line with the naming conventions in the standard library, and the move is because it doesn't make sense to have clocks defined in stop_watch.

Reviewed By: Orvid

Differential Revision: D6329551

fbshipit-source-id: 09d9a48eb47b8fd3761a1bd4350d9ca748fe1f96

Include synchronization/SaturatingSemaphore.h in the makefile

Summary:
It was missing, so it wasn't being installed.

Fixes https://github.com/facebook/folly/issues/727

Reviewed By: Orvid

Differential Revision: D6642322

fbshipit-source-id: 70c10e1265410f73b6c0cd759ce51a5176bfef83

Tweaks to folly::call_once and folly::once_flag

Summary:
[Folly] Tweaks to `folly::call_once` and `folly::once_flag`.

In particular:
* Move the template class out of `detail`.
* Add parameterization by the atomic type.
* Expand the comments.

Reviewed By: Orvid

Differential Revision: D6637250

fbshipit-source-id: 3806580ca0badf8464f637750c4873b2aba9f916

Added remove_cvref

Summary:
std::remove_cvref is like std::decay, but without the function to
pointer and array to pointer decays

Backport of http://en.cppreference.com/w/cpp/types/remove_cvref

Reviewed By: yfeldblum

Differential Revision: D6639513

fbshipit-source-id: 2a5e252678aacc09acf6ce4565872e7efb9b48f3

folly::Indestructible interface improvement

Summary:
As it stands the user cannot use initializer list constructors in the
underlying type, this fixes that and provides a good interface change.
This allows them to use list initialization, which works with initializer
lists

Reviewed By: yfeldblum

Differential Revision: D6620994

fbshipit-source-id: c29199f97b434d84dd8d4cee2f00c5eccb316166

synchronization/ParkingLot

Summary:
A ParkingLot API inspired by linux futex syscall, and WebKit's parkingLot.

Extends the futex interface with lambdas, such that many different sleeping abstractions
can be built.

Reviewed By: yfeldblum, aary

Differential Revision: D6581826

fbshipit-source-id: dba741fe4ed34f27bfad5f5747adce85741441e0

Add getVia and getTryVia to SemiFuture.

Summary: Add getVia and getTryVia to SemiFuture to allow driving chains of work conveniently in the current thread.

Reviewed By: yfeldblum

Differential Revision: D6631898

fbshipit-source-id: 324ef342a44d4ef502188b3cffde17103f0e6cb2

Move getTry to subclasses.

Summary:
Move getTry from FutureBase to Future and SemiFuture.

Make SemiFuture version move the result out for consistency with get.

Reviewed By: yfeldblum

Differential Revision: D6638561

fbshipit-source-id: 551c0f06ed52ef6d8976a5971a5e90b3ab793da0

Add continuation to semifuture return test.

Summary: Add more detail to testing return of SemiFuture from a continuation to ensure correct behaviour.

Reviewed By: yfeldblum

Differential Revision: D6637565

fbshipit-source-id: 096a7ca140e6bdef7baab6725e86d25cf79742d8

Add deprecation comments to folly::makeFuture.

Summary:
To ensure that we do not end up with continuable futures without attached executors we should deprecate folly::makeFuture. In most cases folly::makeSemiFuture is adequate here.

This diff only adds comments to dissuade future use.

Reviewed By: yfeldblum

Differential Revision: D6628800

fbshipit-source-id: c2b91df351cc5980c1bfb752f7536d320ef8168a

Add getSemiFuture to folly::SharedPromise

Summary: Adds getSemiFuture functionality to folly::SharedPromise. Implements getFuture in terms of this, using folly::InlineExecutor to ensure that there is no change of behaviour.

Reviewed By: yfeldblum

Differential Revision: D6628723

fbshipit-source-id: 0ce7c7773b9290998ce87f84fa5d82ba957f0313

Namespacing and comments in folly/Likely.h

Summary:
[Folly] Namespacing and comments in `folly/Likely.h`.

This adds `FOLLY_LIKELY` and `FOLLY_UNLIKELY`.

Reviewed By: Orvid

Differential Revision: D6636136

fbshipit-source-id: da93220201cabca91b4477ab98269a0febb735db

Tweaks to AtomicStruct

Summary: [Folly] Tweaks to `AtomicStruct`.

Reviewed By: Orvid

Differential Revision: D6636432

fbshipit-source-id: 274c118a732287219c569d7d3f4e170f275518f1