Summary: Fix a few `-Wsign-compare` violations

Reviewed By: @meyering

Differential Revision: D2527969

fb-gh-sync-id: 140acbd06eedf2e2a315e1927b331ff5efb20d0f

Summary: Make folly `-Wpessimizing-move` clean:

Common errors:
```lang=bash
folly/io/test/NetworkBenchmark.cpp:71:30: error: moving a temporary object prevents copy elision [-Werror,-Wpessimizing-move]
    unique_ptr<IOBuf> next = std::move(head->pop());
                             ^
folly/io/IOBufQueue.cpp:153:28: error: moving a temporary object prevents copy elision [-Werror,-Wpessimizing-move]
      appendToChain(head_, std::move(
                           ^
folly/IPAddressV6.cpp:341:12: error: moving a local object in a return statement prevents copy elision [-Werror,-Wpessimizing-move]
    return std::move(ip);
           ^
folly/IPAddressV6.cpp:341:12: note: remove std::move call here
    return std::move(ip);
           ^~~~~~~~~~  ~
1 error generated.
```

Reviewed By: @fugalh, @meyering

Differential Revision: D2526950

fb-gh-sync-id: 49291a8b49905eb9b2042d004830ff2f599dfbd3

Summary: current wangle has no way to close socket write side. writeFlags is extended so that wangle/AsyncSocketHandler can distinguish closeNow(), closeWithReset() and shutdownWrite()

Reviewed By: @viswanathgs

Differential Revision: D2522056

fb-gh-sync-id: 60616176d78311a4a09f9761a6ccda01dd502a88

Summary: Right now ThreadLocal & friends don't operate correctly when used as a
static variable (which is the idiomatic way to use them). The TLS id is
allocated in the static constructor so anybody who uses the ID prior to
first use would use an invalid ID. This makes ThreadLocal unusable for core
code such as per-thread reference counting.

This diff allocates the ID on first use. By making the invalid ID maxint we
avoid adding any extra branches in the fast path. We can then make the
constructor a constexpr meaning that initialization will happen prior to
any code running.

Reviewed By: @meyering

Differential Revision: D2457989

fb-gh-sync-id: 21d0c0d00c638fbbd36148d14d4c891f66f83706

Summary: objdump was showing that the shiftXXX tables are being generated each
time this file is included. For example, HHVM has about 200 of each
of the 4 tables. Since each one is 512 bytes this is 400 KB. I'm not
quite sure why this was happening -- I'd think that the linker would
combine a constant table that was identical.

I think the best thing to do here is just to use extern template. This
way you there's only one copy of the table and you don't have to parse
all of this code in every file

Reviewed By: @yfeldblum

Differential Revision: D2506571

fb-gh-sync-id: b01a522c536a2ff4136340245cacaa33897afefb

Summary: [Folly] Fix Build: GCC 4.9 has `std::make_unique` but not `__cplusplus >= 201402L`.

Reviewed By: @igorsugak

Differential Revision: D2528584

fb-gh-sync-id: 9ad0567429698fb1320ad4066ee06add31acbd57

Fix configure script bug on Mac OS X

Summary: Allow notification upon async eager initialization completion.

Reviewed By: @luciang

Differential Revision: D2518925

fb-gh-sync-id: 95f96da2afa6e5953630dd935d74819521716e5f

Summary: Fixes facebook/folly#323

Reviewed By: @JoelMarcey

Differential Revision: D2518882

Pulled By: @fredemmott

fb-gh-sync-id: fc0a07d925945f7d7e1cddb7302c8bf18e0130ab

Summary: Because MSVC doesn't support the latter.
Closes https://github.com/facebook/folly/pull/271

Reviewed By: @meyering, @fredemmott

Differential Revision: D2283975

fb-gh-sync-id: d021f739ceead9998b8fedbbd95f22ec9fe949b2

Summary: Tested in:
Distro: Fedora 20 - x86_64
kernel: 3.19
compiler: gcc version 4.8.3
Closes https://github.com/facebook/folly/pull/320

Reviewed By: @sgolemon

Differential Revision: D2519083

fb-gh-sync-id: 07b1437326c393c99feeb6e0764d664d3e22faea

Summary: Singletons requires Futures, and Futures indirectly (via HHWheelTimeKeeper) require Singletons.  This breaks the dependency.  It removes a Future-using API which will be replaced with a better alternative.

Reviewed By: @luciang

Differential Revision: D2517807

fb-gh-sync-id: 93df371a74d0f80dc8c55fb0eadd0b688b27b525

Summary: Move some methods which are generally only used during initialization time (registration, eager-init functions) from the header to the .cpp file

Reviewed By: @luciang

Differential Revision: D2513043

fb-gh-sync-id: 58d1f6e0d158d805a12b8d267421927b3cfc6118

Summary: [Folly] Remove evil `using` statements from `AsyncSSLSocket.h`.

`using` in headers is frowned upon.

Consider this diff a frown.

Reviewed By: @alandau

Differential Revision: D2509810

fb-gh-sync-id: 4a752b9f4a5be6ac4ca7c498c0168ffad5c35d7f

Summary: smallandbroken

Reviewed By: @fugalh

Differential Revision: D2509021

fb-gh-sync-id: 5e379b82615117df89cbc12943fdbe92511c067e

Summary: Stacktraces and more details can be found in the associated task
http://clang.llvm.org/docs/AttributeReference.html#no-sanitize-clang-no-sanitize seems to be the new hotness to disable sanitizers.

Reviewed By: @yfeldblum

Differential Revision: D2510320

fb-gh-sync-id: 01cce68733509a6f5bcf9dbe3a4af6fc2792a43b

Summary: It works fine, this proves it.

Reviewed By: @yfeldblum, @​jkron

Differential Revision: D2509771

fb-gh-sync-id: 28805a1e1db433d3d9a44b9d33f81e30333e44ab

Summary: If it is, return false.

Reviewed By: @siyengar

Differential Revision: D2503765

fb-gh-sync-id: 36b5e2e8cabc2a5157735637be6ca3414005da81

Summary: The move constructor of `fbstring` generates a large amount of code, preventing it to be inlined, and it is inefficient for small strings. This diff fixes both problems.

Reviewed By: @yfeldblum

Differential Revision: D2505762

Summary: title

Reviewed By: @yfeldblum

Differential Revision: D2506703

Summary: AsyncPipe is already open source

Reviewed By: @yfeldblum

Differential Revision: D2506476

Summary: [Folly] Fix Build: `folly/Range.h` for build platforms missing SSE42 headers.

We make the assumption that if the compiler defines the appropriate symbols indicating SSE42, that the corresponding intrinsics headers are available.

We also remove `Range.cpp` from `Makefile.am`, which we forgot to do in the blamed diff.

Reviewed By: @nbronson

Differential Revision: D2504934

Summary: I noticed myself trying to fake this kind of callback for a log-based test I was writing. It seems much nicer to add the callback to `CaptureFD` than roll ugly wrappers around it to do the same thing.

Reviewed By: @yfeldblum

Differential Revision: D2506106

Summary: [Folly] Converge `folly::make_unique` to C++14's `std::make_unique`.

The primary use-case of ther deleter variety of `folly::make_unique` is `DelayedDestruction`. Let the classes matching this use-case define their own factories.

Reviewed By: @fugalh

Differential Revision: D2495718

Summary: [Folly] Support SSE-enabled `Range` functions under Clang.

Basically, we remove GCC-only -isms. In particular, we use only names from the `<emmintrins.h>` and `<smmintrins.h>` headers, instead of the GCC-specific SSE builtins that the original code uses.

But in order to get this to work, we must split out the SSE-enabled functions into their own sources and compile them with the `-msse4.2` flag. There is a way to get around this in GCC by marking individual functions as SEE-enabled, but that technique is not supported in Clang. This is the new `RangeSse42` module.

And in order to do that, we must split out the code that is called by both the original `Range` and the new SSE-enabled functions into yet a third module, `RangeCommon`.

Ahhhhhh, dependencies.

Note that we always compile the SSE-enabled functions, but we only run them on architectures supporting SSE. The original code tests the CPU's capabilities before running any SSE-enabled functions; this change retains that check.

Reviewed By: @nbronson

Differential Revision: D2428983

Summary: This diff fixes the compiler warnings emitted by gcc-4.9's
stricter -Wsigned-comparison check, as well as those revealed by
-Wunused-variable.

Reviewed By: @meyering, @yfeldblum

Differential Revision: D2494514

Summary: Server can find out client's common name through
Cpp2ConnContext::getPeerCommonName

Reviewed By: @siyengar

Differential Revision: D2469588

Summary: fix typo

jenkins and oss build (e.g. travis) failing.

Reviewed By: @pavlo-fb

Differential Revision: D2499462

Reviewed By: @afrind

Differential Revision: D2466921

Summary: On a (broken) unit test there is a bad `CHECK` during destruction time.  This triggers an ABRT, goes through the signal handler, and in the process ends up doing a use-after-free.

Moved some globals inside the functions in which they are used (w/ little duplication, as they are used in one place, mostly).

Reviewed By: @luciang, @meyering

Differential Revision: D2494046

Summary: This diff adds UpdateableSharedPtr and FastUpdateableSharedPtr classes to folly. They are efficiet RCU-style holders for a shared_ptr. See the comment at the top of UpdateableSharedPtr.h for a more detailed description and benchmark results.

All the added files are copied from logdevice code with (almost) no changes (`logdevice/common/` on branch `origin/logdevice-latest`). We've been using them in logdevice for a few months. D1821723 introduced it.

Reviewed By: @​bmaurer

Differential Revision: D1919702

Summary: [Folly] Extract `SparseByteSet` into its own module.

`SparseByteSet`, formerly `FastByteSet`, is actually a generic, fully standalone class. It does not need to be embedded in `Range.cpp`.

Reviewed By: @​bmaurer

Differential Revision: D2460180

Summary: From the client perspective, we set the list in order of
preference once and call into openssl to do the selection. This adds
a little more flexibility in that client optionally can customize the
selection for each negotiation. added tests for the no-op case and the
customized case. Feel free to suggest improvements.

Reviewed By: @afrind

Differential Revision: D2489142

Summary: It's pretty common during parsing protocols with cursors
that there will be empty iobufs along the way.

This changes it so that we prune empty IOBufs in the cloned
output before returning it to the user.

Reviewed By: @djwatson

Differential Revision: D2464488

Summary: AsyncPipeReader and AsyncPipeWriter are classes to asynchronously
read and write to pipes.

Reviewed By: @djwatson

Differential Revision: D2479514

Summary: [Thrift] CodeMod `apache::thrift::async::TEventBase` to `folly::EventBase` (remainder).

A few straggler bits left out of D2349828.

Reviewed By: @Gownta

Differential Revision: D2489063

Summary: sorry

Reviewed By: @​chiunlin

Differential Revision: D2485925

Summary: These classes are likely to be used as static variables and can
easily be constructed with constexpr.

One that we really ought to fix is SpinLock. Sadly we have a bunch of
implementations of it some of which need initialization.

Reviewed By: @meyering

Differential Revision: D2459355

Summary: * `registrationComplete` has a slightly different interface (uses enums now)
* `void doEagerInit()` method initializes synchronously; `Future<Unit> doEagerInitVia(Executor*)` now available.

Reviewed By: @luciang, @meyering

Differential Revision: D2463464