Summary: `decodeVarint` now accepts all of `StringPiece`, `MutableStringPiece`, `ByteRange`, and `MutableByteRange`.

Test Plan: fbconfig -r folly unicorn/utils && fbmake runtests_opt -j32

Reviewed By: ott@fb.com, lucian@fb.com

Subscribers: trunkagent, chaoyc, search-fbcode-diffs@, unicorn-diffs@, folly-diffs@, yzhan, yfeldblum

FB internal diff: D1836805

Signature: t1:1836805:1423534085:cca5c3e83ad699e5d56e1d1e3394644ec3f94dab

Summary: Correct typo on docs.

Test Plan: N/A

Reviewed By: alikhtarov@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1836264

Signature: t1:1836264:1423527402:4e5f263f446346f7145c33c671f0b9e694db15fd

Summary:
include was missing, causing build to fail on
Arch Linux with gcc 4.9.2 -- found this while resolving
other issues.

Test Plan: build folly on my personal linux and on dev server

Reviewed By: viswanath@fb.com

Subscribers: fugalh, folly-diffs@, jsedgwick, yfeldblum

FB internal diff: D1835143

Signature: t1:1835143:1423513128:5dcff69a82878f47b40512711ed254f239399c2c

Summary:
This reverts commit 4893c09795ad4b1187518b184ac4812079039988.

Fix unit test in D1823663.

Test Plan: fbconfig -r folly fbmake dbg

Reviewed By: alikhtarov@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1832645

Signature: t1:1832645:1423267466:6012f1d7700d540c7290c29b01b33148cf91183c

Summary:
Under Linux the process gtod doesn't contain the current cpu, so
__vdso_getcpu uses RDTSCP, which makes it cost about 20 nanos.  The gtod
_does_, however, contain a nanosecond time (for CLOCK_REALTIME_COARSE)
updated during context switches.  This diff adds a TLS cache that uses
__vdso_clock_gettime_ns(CLOCK_REALTIME_COARSE) to detect context switches.
The end result is that AccessSpreader goes from ~20 nanos to ~6.

Test Plan: unit tests

Reviewed By: davejwatson@fb.com

Subscribers: yfeldblum, trunkagent, folly-diffs@

FB internal diff: D1798922

Signature: t1:1798922:1423264298:32312a5e9bddb3b8aa630c146ef708164a6a4651

Summary: This reverts commit 315cfed207895455ecd359d0c1b9d98f28ed0519.

Test Plan:
fbconfig -r folly && fbmake dbg

Reviewed By: robbert@fb.com

Subscribers: sdwilsh, folly-diffs@, yfeldblum

FB internal diff: D1831932

Signature: t1:1831932:1423258329:0962b939a93bbf1722a9e1c90090dcc024b63765

Blame Revision: D1823663

Summary: [Folly] Dedupe the implementations of EventBase::runInEventBaseThreadAndWait.

Test Plan:
Unit tests:
* `folly/io/async/test/EventBaseTest.cpp`

Reviewed By: subodh@fb.com

Subscribers: trunkagent, folly-diffs@, yfeldblum, dougw, brettp

FB internal diff: D1826291

Signature: t1:1826291:1423225534:42264d8dcc8adec6b90ac8a3d6ce1f4b98f29297

Blame Revision: D1810764, D1823407

Summary: This makes test SingletonVaults more similar to global SingletonVault. It also ensures that every SingletonVault is a singleton, which allows potential optimization of making each SingletonEntry a Singleton too, which itself will make get/get_weak as efficient as get_fast/get_weak_fast.

Test Plan: unit test

Reviewed By: chip@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1823663

Signature: t1:1823663:1423188884:4ab2b47cfba270a66613f6f2458b6affc0ed96ad

Summary:
we still make the new Future, but assign it to ourselves. this avoids the following buggy pattern that people might expect to work

```
auto f = ...
f.wait();

// Careful. f.value() was moved out into the new Future, so you may have lost something
someOperationOn(f.value());

// Nope. We already set a callback internally in wait()
f.then(...);
```

Test Plan: unit

Reviewed By: davejwatson@fb.com

Subscribers: exa, yfeldblum, trunkagent, fbcode-common-diffs@, sammerat, cold-storage-diffs@, folly-diffs@, jsedgwick, aflock

FB internal diff: D1809040

Tasks: 6048284

Signature: t1:1809040:1422900812:1b416408eb5eaa71e88778c9c22ed8bfba087efe

Summary: We're using StringKeyed* from common/datastruct to avoid unnecessary string creation whenever we're looking up string keys. C++14 does offer a solution, see e.g. http://stackoverflow.com/questions/10536788/avoiding-key-construction-for-stdmapfind. That is not supported by current compilers.

Test Plan: unittests

Reviewed By: pavlo@fb.com

Subscribers: trunkagent, net-systems@, folly-diffs@, yfeldblum

FB internal diff: D1825700

Signature: t1:1825700:1423086724:530550c3c80e33c80900f31c0ade05c66b22cbe8

Summary:
Before this diff the code below compiled and did absolutely nothing of interest:

StringPiece fun();
...
fun() = "hello";

i.e. assignment to an rvalue range was allowed. Such code is almost always, if not always, in error. This diff fixes that.

Test Plan: ran unittests

Reviewed By: ldbrandy@fb.com

Subscribers: mpawlowski, net-systems@, folly-diffs@, yfeldblum

FB internal diff: D1825360

Signature: t1:1825360:1423097817:fdaaf893cd1abbe71dc857a315df7c45cb6a0bd0

Summary: Eliminated a potential race condition by removing unnecessary code.

Test Plan: Unit tests pass.

Reviewed By: lesha@fb.com

Subscribers: tudorb, trunkagent, folly-diffs@, yfeldblum

FB internal diff: D1824924

Signature: t1:1824924:1423102017:6bce388dccf9126d6ac3a1741d8300a51c5276ed

Blame Revision: D1492526

Summary: [Folly] Avoid EventBase depending on Baton (mutex/condvar variant).

Test Plan:
Unit tests:
* folly/io/async/test/EventBaseTest.cpp

Reviewed By: subodh@fb.com

Subscribers: trunkagent, fma, folly-diffs@, yfeldblum, dougw, brettp

FB internal diff: D1823407

Signature: t1:1823407:1423088450:71ae1673ed8067103e2aaa1ac9b239eae9ebe9de

Blame Revision: D1810764

Summary: It is true. Also, add a useful message about which thread this Future will complete in.

Test Plan: it should still compile

Reviewed By: davejwatson@fb.com

Subscribers: trunkagent, exa, folly-diffs@, jsedgwick, yfeldblum

FB internal diff: D1819849

Tasks: 5705286, 6008465

Signature: t1:1819849:1423074012:79bf11c877eb2f061cb5d07f7ab45fa4cc4a894b

Summary:
(or func returns Future<T>)

Invoke and respond to a timeout with a callback, rather than using `within` and adding `onError` or `then` or something.

Test Plan: new tests

Reviewed By: davejwatson@fb.com

Subscribers: jsedgwick, yfeldblum, trunkagent, fugalh, exa, folly-diffs@

FB internal diff: D1763174

Tasks: 4548494

Signature: t1:1763174:1423074062:05cec1dfb1110b31b599033949ebe0ee70dd0552

Summary:
I don't know what this paragraph is even saying. It looks like
copypasta

Test Plan: still compiles or my uncle is a monkey

Reviewed By: davejwatson@fb.com

Subscribers: trunkagent, exa, folly-diffs@, jsedgwick, yfeldblum

FB internal diff: D1819905

Tasks: 5705286

Signature: t1:1819905:1423074021:a095fe2a17d5698678a527b60c9384625df869fd

Summary:
The `memchr()`-based `find_first_of()` behaves extremely badly when it's used in a loop and the input string doesn't contain all the needles. This was discovered when a reasonable line-breaking routine tried to use it to break lines by a mix of '\r' and '\n'. The entire remainder of the file was scanned each time a line was read.

Before:

```
CountDelimsBase                    1.26s   794.86m
CountDelimsNoSSE         100.03%   1.26s   795.12m
CountDelimsStd         40501.63%   3.11ms  321.93
CountDelimsMemchr         98.31%   1.28s   781.41m
CountDelimsByteSet     23162.41%   5.43ms  184.11
```

After:

```
CountDelimsBase                   3.20ms  312.08 <-- Base impl no longer considers memchr
CountDelimsNoSSE         102.37%  3.13ms  319.47
CountDelimsStd           103.19%  3.11ms  322.05
CountDelimsMemchr          0.25%  1.27s   788.39m
CountDelimsByteSet        59.68%  5.37ms  186.27
```

Test Plan: Benchmarks

Reviewed By: njormrod@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1823536

Signature: t1:1823536:1423081687:bb2ec8cdea477ee9b9c8d8ad2bfdecdc52657515

This reverts commit 462e13b1.

fix configure script to check pthread_atfork(3) in the correct way

Test Plan: fbmake runtests

Reviewed By: chip@fb.com, pavlo@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1825369

Signature: t1:1825369:1423080185:8507643a3f8860bae6a2240e0ae28fbaf2885b12

Summary:
As a replacement for makeFuture().  The main advantage is for non-void futures, implicit conversion works pretty well.

See unittest for examples

Test Plan: fbconfig -r folly/futures; fbmake runtests

Reviewed By: hannesr@fb.com

Subscribers: yfeldblum, trunkagent, doug, folly-diffs@, jsedgwick

FB internal diff: D1806575

Signature: t1:1806575:1422465608:6099f791591b70ce1bcda439b49307b8f3187d89

Summary:
Even though the benchmark only keeps the first 10 lines, it gets slower the bigger the "file" is.

```
folly/gen/test/StringBenchmark.cpp              relative  time/iter  iters/s
----------------------------------------------------------------------------
Lines_Gen(1e3)                                               5.53us  180.94K
Lines_Gen(2e3)                                    66.43%     8.32us  120.21K
Lines_Gen(3e3)                                    48.26%    11.45us   87.33K
```

Test Plan: Benchmarks

Reviewed By: lesha@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1823545

Tasks: 6155600

Signature: t1:1823545:1423023712:86fdb3dadbec44195e4b3596cf793cea80ae3a76

Summary:
When closing sockets on retry, we should use `shutdownSocketSet_`
if it is set (so socket will properly be removed from the set).

Also I changed all `::close()` and `::shutdown()` calls to `*NoInt()`
version.

Test Plan:
fbconfig unicorn/test:basic_compression_test && fbmake opt -j32
while _bin/unicorn/test/test:basic_compression_test; do echo DONE; done

Reviewed By: mcduff@fb.com

Subscribers: trunkagent, folly-diffs@, yzhan, yfeldblum

FB internal diff: D1821104

Tasks: 4752579, 6123510

Signature: t1:1821104:1423001050:5bc09ffdd6666c2884ea82dbd70831a56513cfc9

Blame Revision: D1795120

Summary:
before:

E0203 12:32:34.548096 3354863 [admonitor-local] Singleton.cpp:72] Singleton of type N8facebook12configerator22ConfigeratorStaticDataE has a living reference at destroyInstances time; beware! Raw pointer is 0x7fd6ccc81000. It is very likely that some other singleton is holding a shared_ptr to it. Make dependencies between these singletons are properly defined.

after:

E0203 13:48:09.013022 3913115 Singleton.cpp:72] Singleton of type facebook::configerator::ConfigeratorStaticData has a living reference at destroyInstances time; beware! Raw pointer is 0x7f6f7dc4c000. It is very likely that some other singleton is holding a shared_ptr to it. Make dependencies between these singletons are properly defined.

Test Plan: run it

Reviewed By: chip@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1822466

Signature: t1:1822466:1423000686:345f40fa706701476256a7157468521bc69166a0

Summary: This was only used in a unittest, every real use case uses AsyncServerSocket, and decides on its own to do SSL or not.

Test Plan: fbconfig -r thrift/lib/cpp/test; fbmake runtests

Reviewed By: alandau@fb.com

Subscribers: fugalh, trunkagent, doug, alandau, bmatheny, ssl-diffs@, mshneer, jsedgwick, folly-diffs@

FB internal diff: D1806807

Signature: t1:1806807:1422396209:02333c736e1ef10963e3fe0b4ed6ecf6122475bb

Summary:
Originally meant as a kill switch.  It's turned on in everything except adfinder, so we can probably remove this flag after running a couple adfinder canaries

I have no idea who should review this in ads team, guessed and added some people

Test Plan: https://our.intern.facebook.com/intern/tupperware/canary/view/?experiment_id=32937

Reviewed By: haijunz@fb.com

Subscribers: trunkagent, doug, ruibalp, nli, alandau, bmatheny, wormhole-diffs@, mshneer, folly-diffs@

FB internal diff: D1809255

Tasks: 5645329

Signature: t1:1809255:1422490068:5b4551e6c126d86cac8f8e7b06da6474e6b8a25a

Summary: This diff introduces 5 seconds wait time to let other threads release Singleton which may be temporarily locked. This helps prevent most of "Singleton object alive after destruction" warnings in cases where weak_ptr API is used correctly. Abusive use of folly::Singletons, where dependencies between singletons are not properly defined will still cause a warning.

Test Plan: unit test

Reviewed By: chip@fb.com

Subscribers: trunkagent, folly-diffs@

FB internal diff: D1808371

Signature: t1:1808371:1422487261:573eb40b6a260e428d96be476659335250c7ea76

Summary:
AsyncSocket sets CLOEXEC if it connects an address, but won't
if it uses a connected fd. This sets CLOEXEC for such fd.

Test Plan: fbconfig folly/io/async/test && fbmake runtests

Reviewed By: davejwatson@fb.com

Subscribers: trunkagent, folly-diffs@, zacm

FB internal diff: D1809300

Signature: t1:1809300:1422900997:40fcc84506582ac67076fd975a36d094522c35c2

Summary:
[Folly] EventBase::runInEventLoopThreadAndWait.

Useful for when some code needs to be run in the event loop thread, but another thread needs to trigger the code and then wait for it to be done.

Test Plan:
Unit tests:
* `folly/io/async/test/EventBaseTest.cpp`

Reviewed By: davejwatson@fb.com

Subscribers: trunkagent, folly-diffs@, brettp, dougw

FB internal diff: D1810764

Signature: t1:1810764:1422900654:7ff0aa7feb2792266f620b344cf8a1110a09f7ef

Summary:
Fixing following the issues raised by nsuke on github
following his diff (https://github.com/facebook/folly/pull/112)

Test Plan: visual inspection, tested build on arch linux

Reviewed By: davejwatson@fb.com

Subscribers: folly-diffs@

FB internal diff: D1807378

Tasks: 5909189

Signature: t1:1807378:1422403093:ca024f396a27ecd9b304c57643f0107764a38ca1

Summary:
fetch_and and fetch_or are actually required in some instances,
since the operation they perform isn't reversible.  This also adds some
other missing functions, ^= and fetch_{add,sub,xor}.

Test Plan: use from other code's unit tests

Reviewed By: mssarang@fb.com

Subscribers: yfeldblum, folly-diffs@

FB internal diff: D1798924

Signature: t1:1798924:1422892374:a9859039075ddcac54f75259b9bc6a29bb963a09

Summary: This reverts commit 90da92b05762f8032560d0d6a66237ab2772d7f2.

Test Plan: compiles

Reviewed By: tjackson@fb.com

Subscribers: lins, anca, folly-diffs@, yfeldblum

FB internal diff: D1817376

Tasks: 6118752

Summary:
There was a race reading `callback_` in `maybeCallback` and setting `callback_` in `setCallback`. This diff reworks the state machine to make this unpossible. To avoid the explosion of states due to the cross-product of has-interrupt-handler/has-been-interrupted/etc. I introduce a separate lock for setting interrupt handler and interruption, since this is primarily orthogonal. Other attributes (active, for example) are still atomic variables, and while somewhat tied into the state machine logically (e.g. transitioning from Armed to Done only happens when active) they are mostly independent, keeping the state machine simple (and probably faster).

I think it may even be possible to do some things cheaper. In some states, we may not need to protect the writing of `callback_` and `result_`. But we'd need to enforce some ordering so I'm not going to try to tackle that. But that could be some speedup if we can do it cheaply.

Test Plan:
Builds and all existing tests pass.

Reviewed By: rockyliu4@fb.com

Subscribers: yfeldblum, stepan, trunkagent, exa, folly-diffs@, jsedgwick

FB internal diff: D1807854

Tasks: 6087856

Signature: t1:1807854:1422656713:25b62706cd7952b2dde06dab08074f8030db456b

Summary:
Add a description of the fault-after-unlock problem that can
occur when a synchronization object is used to guard its own
destruction.

Test Plan: comment change only

Reviewed By: alikhtarov@fb.com

Subscribers: trunkagent, folly-diffs@

FB internal diff: D1808446

Signature: t1:1808446:1422481173:83c0369e2277cd5b8cf6377fcd92b132019611a7

Summary: That is, for all inputs except r-values.

Test Plan:
Run tests
@override-test-failures

Reviewed By: ajaymenon@fb.com

Subscribers: trunkagent, folly-diffs@

FB internal diff: D1807789

Signature: t1:1807789:1422410689:442d50ab17f8e3b08e34f33318a4dc7f23b4c6cc

Summary:
This speeds up TLS handshake and might be a factor of liger perf regression.
The enabling is guarded by an #ifdef. The condition itself is defined in an
openssl patch.

Test Plan: folly unit tests pass. Tried on devices as well and from tcpdump data was sent before the new ticket was received, essentially speeded up the handshake process.

Reviewed By: subodh@fb.com

Subscribers: trunkagent, kmdent, seanc, benyluo, ssl-diffs@, ranjeeth, folly-diffs@

FB internal diff: D1806856

Tasks: 5284979

Signature: t1:1806856:1422494521:0a048ea9001da13b5d698b5a764d1e66dcbedc99