Summary:
I have 2 local buffers and instead of allocating iobufs
on the heap, I can simply use iovec on the stack to send.

Test Plan: Unit tests and turn server.

Reviewed By: davejwatson@fb.com

Subscribers: folly-diffs@, ehrhardt, yfeldblum, chalfant, paramr

FB internal diff: D1956201

Signature: t1:1956201:1427918649:09f00399fd9e8ed3fe62be43b19adbf0a5a3f3b0

Test Plan: unittests

Reviewed By: jbrewer@fb.com, ashishsharma@fb.com

Subscribers: maxime, folly-diffs@, yfeldblum, chalfant

FB internal diff: D1956101

Signature: t1:1956101:1427828321:2d828e6f2c06c6dcd6e7baa3ed5e72ee59d9b77f

Summary:
From reading the docs, I assumed that casting exceptions would be caught.  Let's clarify this.

Test Plan: readingiskey

Reviewed By: yfeldblum@fb.com

Subscribers: folly-diffs@, yfeldblum, chalfant

FB internal diff: D1960186

Signature: t1:1960186:1427920471:b7aa2af38a90a986418b98294fc0f69e678f0d1e

Summary:
Taking this trick that is used in the fibers library. We can keep 64
bytes of space inside `Core` to allocate the callback lambda into,
instead of having `std::function` do another `malloc`. This seems to
greatly improve the synthethic benchmark, and hopefully production
workloads, too, by reducing the number of mallocs.

64 bytes were picked because it fits all the lambdas in the futures
tests. We might want to adjust this based on production data...?

https://fb.intern.facebook.com/groups/715931878455430/permalink/837898842925399/

Test Plan: Run all the tests for all platforms, compilers, and Windtunnel.

Reviewed By: hans@fb.com

Subscribers: chalfant, meisner, folly-diffs@, jsedgwick, yfeldblum

FB internal diff: D1931620

Signature: t1:1931620:1427841595:6ec667b58980be232dfb116bc316148bb67de4fc

Summary: In a couple places in ServerBootstrap there is code that needs to run in the EB, but if we are already in the EB, it's fine to run it inline.  Maybe this should be a method on EB directly?  There is runInEventBaseThreadAndWait(), but it explicitly disallows this usage.

Test Plan: used in D1942242, deadlocks without this, since stop() was called in the same eb

Reviewed By: yfeldblum@fb.com

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

FB internal diff: D1947581

Signature: t1:1947581:1427831021:d1d08ff9a4a00501d6be60670709fcb17af04134

Summary:
The current behaviour of SSLContext is subject to a bug where an instance going
out of scope at the wrong time can decrement the global refcount to 0, causing
the destructor to destroy the SSL context. Instead, this requires callers to
explicitly uninitialize the SSLContext instance and assume the risk of wrongly
destroying the global SSL context.

Test Plan:
Tested with mcrouter

Reviewed By: subodh@fb.com

Subscribers: afrind, ssl-diffs@, folly-diffs@, yfeldblum, chalfant, dihde, melitam

FB internal diff: D1949649

Tasks: 6358211

Signature: t1:1949649:1427854689:aea2dc801f63256ff64188b0f7a15121dcecee69

Summary: as title

Test Plan: run unit tests

Reviewed By: yfeldblum@fb.com

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

FB internal diff: D1955074

Summary:
If an MPMCQueue was initialized with an explicit zero capacity, it would
try to compute stride for zero and trigger SIGFPE which pretty fatally
killed the process -- but in a way that required gdb to figure out the
root cause.

This replaces that with a std::invalid_argument exception, which
includes a description of the problem and should make fixing this user
error much faster.

Test Plan:
GTEST unit test added to verify behaviour; if this didn't work it would
SIGFPE and abort the test script, which is probably a good indicator
that something went wrong. :)

fbconfig -r folly && fbmake runtests

Reviewed By: ngbronson@fb.com

Subscribers: chalfant, folly-diffs@, yfeldblum, rkomorn

FB internal diff: D1930978

Signature: t1:1930978:1427740315:cc06a8b9f3c314b956ae41f813b2f904d3e979c9

Summary: Since Acceptor can be used for TCP or UDP, make an empty default TCP accept function so subclasses don't have to.

Test Plan:
built D1942242, no build errors

contbuild

Reviewed By: yfeldblum@fb.com

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

FB internal diff: D1948940

Signature: t1:1948940:1427498977:26b7bb23e3367ff6695dad86ebf0e60637815a7b

Summary:
[Folly] EventBase::runImediatelyOrRunInEventBaseThreadAndWait.

When you have code that you need to run in the event loop and wait for it to finish, and you yourself might be in the event loop but might be in another thread instead.

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

Reviewed By: davejwatson@fb.com

Subscribers: folly-diffs@, yfeldblum, chalfant, agallagher, njormrod, ldbrandy, brettp, dougw

FB internal diff: D1953110

Signature: t1:1953110:1427751076:ad2c9f4d5b65ef952cba94b06be887672ee44583

Summary:
as title.

Test Plan: run unit tests

Reviewed By: yfeldblum@fb.com

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

FB internal diff: D1946589

Summary: as title

Test Plan: run unit tests

Reviewed By: yfeldblum@fb.com

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

FB internal diff: D1950610

Summary:
AsyncUDPSocket supports reuse port, also make it available in AsyncUDPServerSocket.
Has to happen before bind

Test Plan:
?? it builds?

Mutliple binds already work with reuseaddr, but load balancing doesn't work as well.  See http://lwn.net/Articles/542629/ for details

Reviewed By: naizhi@fb.com

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

FB internal diff: D1948932

Signature: t1:1948932:1427473013:8c114458a0746bb2b6957db33c1834179d860c00

Test Plan: new unit tests

Reviewed By: davejwatson@fb.com

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

FB internal diff: D1828251

Tasks: 6166893

Signature: t1:1828251:1427475565:512463d5728482a40c1da2548a5bed91e7f92d60

Summary:
Without a gadget like this, it's really hard to test logging output. With it, it's really easy. I found about 50 callsites to the various functions across several projects, so folly seems appropriate.

PS The patterns are functions for two reasons:
- Static variables are a pain.
- This leaves the option of adding an optional argument, so you can grep for a particular kind of error string.

Test Plan: unit test

Reviewed By: yfeldblum@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1933439

Signature: t1:1933439:1427345479:5b3d1c6566a026fdbccb16b382211688e327ea1a

Summary: There are about 40 callsites to these across a couple of projects, and they seem generally useful.

Test Plan: ```fbconfig folly/experimental/test && fbmake runtests```

Reviewed By: yfeldblum@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1933415

Signature: t1:1933415:1427345307:6587eea3dac74c5d841950ace3c3501d6e3dbe4a

Summary:
TemporaryFile, TemporaryDirectory, and ChangeToTempDir should all be moveable
objects, but not copiable.  Define default move constructors and move
assignment operators for these classes.  This will prevent copy constructor and
copy assignment operators from being implicitly defined.

Test Plan:
Used this in a new test to write a helper function which created and returned
a new TemporaryFile object using the move constructor.

Reviewed By: yfeldblum@fb.com

Subscribers: doug, net-systems@, exa, folly-diffs@, yfeldblum

FB internal diff: D1945134

Signature: t1:1945134:1427342944:3428327e797ce4b3d362f9a2d2276de6d8b96137

Summary:
1] The lambda should ble able to return a `Try<T>`. Maybe? Can a `then`
return a `Try<T>` actually? Can fix this with `resultOf`. (Doubling the number of functions to 4.)

2] `initial` and `func` have to be copyable.

Test Plan: Added tests.

Reviewed By: hans@fb.com

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

FB internal diff: D1870996

Tasks: 6025252

Signature: t1:1870996:1427318511:2ae5894b79022da88990835b26d35c4520fdbd29

Summary: Make it easy for people to mark code as deprecated

Test Plan: Chose a random file and added the FOLLY_DEPRECATED macro to it

Reviewed By: yfeldblum@fb.com

Subscribers: ps, folly-diffs@, yfeldblum

FB internal diff: D1943248

Signature: t1:1943248:1427316689:b3305d134f374697e93d36bafbf0961eec1ef68a

Summary:
vsnprintf can return fewer bytes and bytes_used if
we print a string containing '\0' using a width
specifier.

Test Plan: -- ran all tests

Reviewed By: andrei.alexandrescu@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1915035

Signature: t1:1915035:1426799341:4aaea928c4bdde1998bf66cf9e2732a53572c6e3

Summary:
Original diff D1800100, reverted in D1895181.  Issue seems to have been caused by a copy constructor issue.

Fixes: Remove copy constructor, move contructor only.  Separate stop() and join(), since join() can happen only after all stop()s have completed when reusing the same IOThreadPoolExecutors.

Test Plan: build and unit tests of relevant product

Reviewed By: praveenr@fb.com

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

FB internal diff: D1901718

Tasks: 6431975

Signature: t1:1901718:1426885577:46b63bfe117df207be3d273b953c100249c1a7da

Blame Revision: D1895181

Summary: It's convenient to be able to write tempfiles in the current directory. This provides a one-liner way of doing that in tests.

Test Plan: unit test

Reviewed By: yfeldblum@fb.com

Subscribers: simpkins, folly-diffs@, yfeldblum

FB internal diff: D1931918

Signature: t1:1931918:1426913634:f988fb3c5061f5909e309dcaf42742d9b2ed18c6

Summary: We want to print all destructor stack-traces if Singleton destruction happens eventually (even after destroyInstances() was done).

Test Plan:
unit test

Reviewed By: chip@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1929881

Signature: t1:1929881:1426878091:5993d544c0f84bdbf8bcdd420ef01fb7bf88ac3f

Summary:
major changes:

1) ServerSocketFactory and AsyncSocketBase to abstract the differences between UDP and TCP async socket.  Could possibly push some of this to the sockets themselves eventually
2) pipeline() is a pipeline between accept/receive of a UDP message, and before sending it to workers.  Default impl for TCP is to fan out to worker threads.  This is the same as Netty.  Since we don't know if the data is a TCP socket or a UDP message, it's a void*, which sucks (netty uses Object msg, so it isn't any different).

Test Plan: Added lots of new tests.  Doesn't test any data passing yet though, just connects/simple receipt of UDP message.

Reviewed By: hans@fb.com

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

FB internal diff: D1736670

Tasks: 5788116

Signature: t1:1736670:1424372992:e109450604ed905004bd40dfbb508b5808332c15

Summary:
This code is only used in a test so far.

Basically it looks like Pipeline has some dependency issues - any addBack() pipelines have to be deleted *after* the main pipeline is destroyed.  Ideally if the pipeline is already closed, the destruction order wouldn't matter.  There is currently no removeBack() call either.   This is a quick fix for the test to just delete stuff in the right order, we can discuss a better solution when @jsedgwick returns

Test Plan: fbconfig --sanitize=address --with-project-version=clang:3.5 --clang folly/wangle/service && fbmake runtests

Reviewed By: hans@fb.com

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

FB internal diff: D1903200

Tasks: 6415578

Signature: t1:1903200:1426528298:e109dcc0ec586a505a26cd95a6f20434d22cbd37

Summary:
In my tests, using djb2 was much worse for any sizable workload. Just use SpookyHashV2.

Test Plan: comment only

Reviewed By: tudorb@fb.com

Subscribers: trunkagent, folly-diffs@, yfeldblum

FB internal diff: D1906439

Signature: t1:1906439:1426117575:f88b7b28b578092c1716433e21150d423d4e94a7

Summary:
Calling getaddrinfo from a static constructor is not the most
reliable thing to do. Stop doing it.

Test Plan: existing tests

Reviewed By: davejwatson@fb.com

Subscribers: dancol, mzlee, shikong, kmdent, fma, bmatheny, benyluo, ranjeeth, folly-diffs@, jsedgwick, yfeldblum

FB internal diff: D1924578

Tasks: 6534662

Signature: t1:1924578:1426718586:d73bc2f001095e66fa77fde9c027af050cc26d2a

Summary: I thought this might fix #6120972. But it doesn't. Still a bit of a cleanup in my opinion.

Test Plan: Run all the tests?

Reviewed By: hans@fb.com

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

FB internal diff: D1907259

Signature: t1:1907259:1426613567:9e33fe7e9e8a36ba006d4aee604086a56f128893

Summary:
Sometimes we only want to log if enough time has passed, e.g. when logging
inside of a loop doing work to detect if things are slow. Add an option for
that.

Test Plan:
build and unit tests of folly/experimental

Reviewed By: lesha@fb.com

Subscribers: trunkagent, folly-diffs@, yfeldblum

FB internal diff: D1909055

Signature: t1:1909055:1426627731:6d3ad94fd71967ec89ffebc90cd2907dd1631d36

Summary: Ooops during port ;)

Test Plan: unit test

Reviewed By: agoder@fb.com

Subscribers: trunkagent, folly-diffs@, yfeldblum

FB internal diff: D1905639

Signature: t1:1905639:1426171227:a6e415046a85f098ac090f069476204fb0367c42

Summary: Signed-off-by: Nicholas Ormrod <njormrod@fb.com>

Test Plan: Clicked link, gtest started downloading

Reviewed By: markisaa@fb.com

Subscribers: sdwilsh, folly-diffs@, yfeldblum

FB internal diff: D1901849

Tasks: 6255850

Signature: t1:1901849:1426097071:e887ed8749c70d5e15877082ac0175ce3b56647e

Summary:
BackoffTimeout disallow copy construction, copy assignment, move
construction, move assignment, and default construction.

Closes https://github.com/facebook/folly/pull/146

Test Plan: runtests

Reviewed By: ldbrandy@fb.com

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

FB internal diff: D1912521

Signature: t1:1912521:1426268413:6edb2d8203d1efd1e825816f03be115ac46e55ca

Summary:
It seems we might avoid temporaries.  To do so we pass arguments
directly to constructors with the help of emplace_back member.

Test Plan:
all folly/tests, make check for 37 tests, passed.

Closes https://github.com/facebook/folly/pull/150

Reviewed By: ldbrandy@fb.com

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

FB internal diff: D1912505

Signature: t1:1912505:1426268158:086882bb53f3d79c3f3b7b2c362318f09b5ee3be

Summary:
AsyncServerSocket disallow copy construction, copy assignment,
move construction, move assignment, and default
construction.

Closes https://github.com/facebook/folly/pull/148

Test Plan: all folly/tests, make check for 37 tests, passed.

Reviewed By: ldbrandy@fb.com

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

FB internal diff: D1912488

Signature: t1:1912488:1426267982:a9690ce9429016f89630f0ded64b7be9ff80c39d

Summary: backslash

Test Plan: tests

Reviewed By: aap@fb.com

Subscribers: folly-diffs@, yfeldblum

FB internal diff: D1920872

Signature: t1:1920872:1426624366:c984fecb5bd0c292d5a8309fb320a48872fff6db

Blame Revision: D1890511

Test Plan:
unit tests

Reviewed By: bwatling@fb.com

Subscribers: stepan, folly-diffs@, yfeldblum, trunkagent, vikas, alikhtarov

FB internal diff: D1890511

Tasks: 6311387

Signature: t1:1890511:1425924980:71af7c12a09a86b280dc3c9a9ef0756bf56bf639

Summary: Apparently `configure` creates this subdirectory and then the curl and unzip commands don't run, and then `make check` fails. Instead, do it if the zip file doesn't exist.

Test Plan:
git clone https://github.com/facebook/folly.git
cd folly/folly
/path/to/this/bootstrap-osx-homebrew.sh
make
make check

Reviewed By: andrei.alexandrescu@fb.com

Subscribers: exa, folly-diffs@, yfeldblum, davejwatson

FB internal diff: D1882472

Signature: t1:1882472:1425920470:bdab25967d3b8e52c690d5627168077c65829b92

Summary: for consistency with exception and exception_ptr functions provided in String.h

Test Plan: unit

Reviewed By: vloh@fb.com

Subscribers: trunkagent, folly-diffs@, yfeldblum

FB internal diff: D1905087

Tasks: 5961362

Signature: t1:1905087:1426101740:670ceab5140250bbecdd1247025d3d70b7774690