Summary: Call addTimerFd only after a callback to avoid issuing duplicate poll requests

Reviewed By: danobi

Differential Revision: D20843253

fbshipit-source-id: 9aa538dcc4cc63f1d1a3431d41366ce3fa3644cb

Summary: Handle spurious poll returning 0 when we have high load at process startup time

Reviewed By: danobi

Differential Revision: D20821506

fbshipit-source-id: 93ec91f0908f44e5210974e1cf3f30ac7aa38950

Summary:
gcc-9.3 complains about folly::Format:

```
array subscript -1 is outside array bounds of ‘char [69]’
```

But the warning is incorrect; my guess is that it is confused because
it doesn't realize that higher-level logic guarantees that integer
formatting will run out of digits before it runs out of buffer.

Changing some code from `array + x` to `&array[x]` works around it.

Reviewed By: pixelb

Differential Revision: D20694399

fbshipit-source-id: 1176858054cdec9e415de4829371647958955103

Summary:
In coverage collection mode a special module loader is prepended to
`sys.meta_path`. In very specific conditions this module loader can end up
returning a loader pointing to a _completely wrong module_. When importing
symbols from the wrong module errors occur.

The conditions to trigger the bug are:

- running in coverage collection mode, enabling the custom loader
- the test binary is a zip (e.g. par_style=fastzip)
- having a module name where the end part matches the name of a builtin Python
  module

When these conditions were met, the special loader would return the builtin
Python module instead of the expected module. E.g. when loading a module like
`myapp.somemod.platform` in a zip style binary.

The custom loader first calls `imp.find_module()` to find the module it wants
to return a wrapped loader for. This fails for modules included in the test
binary, because the builtin `imp` module can not load from zips. This was the
trigger leading to the call to the buggy code.

When the initial call to `imp.find_module()` failed, the custom loader would
try a second call, asking the internal loader to this time try any path on
`sys.path`. For most module names this call would also fail, making the custom
loader return `None`, after which Python tries other loaders on `sys.path`.
However, when the final part of the module that was asked to load matches the
name of a Python builtin module, then the second call to the `imp` module would
succeed, returning a loader for the builtin module. E.g. `platform` when asking
for `myapp.somemod.platform`.

This diff fixes the issue by removing the broken second call to the internal
loader. This will never have worked, we just have not triggered or noticed
triggering the wrong loading before.

Differential Revision: D20798119

fbshipit-source-id: dffb54e308106a81af21b63c5ee64c6ca2041920

Summary:
https://www.openssl.org/source/openssl-1.1.1b.tar.gz is gone

changelog:
https://www.openssl.org/news/openssl-1.1.1-notes.html

Reviewed By: udippant

Differential Revision: D20810020

fbshipit-source-id: 0ed385f49b2187ec149defd79feb86e2c8b492d2

Summary:
Change to SemiFuture returning collect, which checks for nullptr passed to via, breaks this test which produced a default nullptr.

Instead remove default and force passing of a valid executor.

Reviewed By: yfeldblum

Differential Revision: D20795552

fbshipit-source-id: 5411fea910d9f85eb5a4ba825a1cfd48a72b8a44

Summary: Add support for specifying which fatal signals to handle

Reviewed By: simpkins

Differential Revision: D20672281

fbshipit-source-id: 16696abcf551efcd932f5b56b336d6c5bc0d7a55

Summary: io_uring backend error handling

Reviewed By: kevin-vigor

Differential Revision: D20737416

fbshipit-source-id: 23eebc98326bcd07ee308e8f71f972c7374f6108

Summary:
I was testing vs2019 vs vs2017 and realized that
we weren't reconfiguring when the toolchain was changed;
this resolves that.

Reviewed By: genevievehelsel

Differential Revision: D20795118

fbshipit-source-id: db80f090367cacfcc6b53887b77cf949f9cef0e6

Summary:
We see flakey builds to conflicting writes to .pdb files; the error
message suggests enabling `/FS` which is already enabled.  Some serious
internet research reveals that we can put the debug info into `.obj` files
instead of having everyone contend with the same `.pdb` file.

```
C:\PROGRA~2\MIB055~1\2017\BUILDT~1\VC\Tools\MSVC\1416~1.270\bin\Hostx64\x64\cl.exe  /nologo /TP -DBOOST_CONFIG_SUPPRESS_OUTDATED_MESSAGE -DGFLAGS_IS_A_DLL=1 -DWIN32_LEAN_AND_MEAN -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_WARNINGS -D_ENABLE_EXTENDED_ALIGNED_STORAGE -D_SCL_SECURE_NO_WARNINGS -D_STL_EXTRA_DISABLED_WARNINGS="4774 4987" -IZ:\shipit\folly -I. -IZ:\installed\boost-6XBjAEHS6zoZVAY7uQHhSxYamF-vUNWngO1YaEIiiko\include\boost-1_69 -IZ:\installed\double-conversion-8uX8TcZDEz7gXyY70bMXqPUF2uLqH2OTWBffkLfU7FU\include -IZ:\installed\gflags-Md0yNU5drHUQ6MCdsB6iC0WS5YX-RFZk_eTHNKjkcPs\include -IZ:\installed\glog-_3NtzkcZDkkSFkgC70vwofqrnao05-mPxEa0E546a9g\include -IZ:\installed\libevent-TIUwVyvnVZZVHDsesjdIidM_iH4er-_6pEE0X4dzuL4\include -IZ:\installed\openssl-0G_glZ7y5BplM752sREIHKuam0GcoPqw7m6yjEGefyE\include -IZ:\installed\zlib-lxujVMVR4hhdh4-S0SCxkb55DAWh5ISCLWbfL7m7hwg\include -IZ:\installed\zstd-M8csiME1A2X7ZGECWeSGmWbqM1glHd6xoskhyPHgpaw\include -IZ:\installed\snappy-Z3WzzGXxgX1-6zSn4NdRg8Z3coQaz7Gob3gGoomN95E\include -IZ:\installed\fmt-W9-akKzyOlf4GoHcFsw1_rCxt3y0ghyjO3gb5Xve1Gc\include /DWIN32 /D_WINDOWS /W3 /GR  /MD /Zi /O2 /Ob1 /DNDEBUG   /EHs /GF /Zc:referenceBinding /Zc:rvalueCast /Zc:implicitNoexcept /Zc:strictStrings /Zc:threadSafeInit /Zc:throwingNew /permissive- /std:c++latest /bigobj /favor:blend /Zc:inline /Wall /MP /Gw /Gy /Qpar /Oi /Ot /wd4191 /wd4291 /wd4309 /wd4310 /wd4366 /wd4587 /wd4592 /wd4628 /wd4723 /wd4724 /wd4868 /wd4996 /wd4068 /wd4091 /wd4146 /wd4800 /wd4018 /wd4365 /wd4388 /wd4389 /wd4100 /wd4459 /wd4505 /wd4701 /wd4702 /wd4061 /wd4127 /wd4200 /wd4201 /wd4296 /wd4316 /wd4324 /wd4355 /wd4371 /wd4435 /wd4514 /wd4548 /wd4571 /wd4574 /wd4582 /wd4583 /wd4619 /wd4623 /wd4625 /wd4626 /wd4643 /wd4647 /wd4668 /wd4706 /wd4710 /wd4711 /wd4714 /wd4820 /wd5026 /wd5027 /wd5031 /wd5045 /we4099 /we4129 /we4566 /showIncludes /FoCMakeFiles\folly_base.dir\folly\Format.cpp.obj /FdCMakeFiles\folly_base.dir\ /FS -c Z:\shipit\folly\folly\Format.cpp

Z:\shipit\folly\folly\Format.cpp: fatal error C1041: cannot open program database 'Z:\build\folly\CMakeFiles\folly_base.dir\vc140.pdb'; if multiple CL.EXE write to the same .PDB file, please use /FS

ninja: build stopped: subcommand failed.
```

Reviewed By: yfeldblum

Differential Revision: D20752325

fbshipit-source-id: 4f20871d54cc0973b3d025734dd0886c202c839b

Summary:
This diff exposes the maximum number of internal stripes
supported by the AccessSpreader, increases that value from 128 to 256
for server platforms, and uses bulk string operations to speed up the
internal initialization. This change only affects the spreading results
on machines with more than 128 hardware threads.

(Note: this ignores all push blocking failures!)

Reviewed By: yfeldblum

Differential Revision: D20772443

fbshipit-source-id: 5c7142efb2bb9ba07cc423195074fc33aeea6dcb

Summary: This helps avoid TSAN false positives.

Reviewed By: yfeldblum

Differential Revision: D20787056

fbshipit-source-id: e62537235e3ad876e3ec5266f9c449d0d8340330

Summary: Detach by destruction is common, and for SemiFutures drops the continuation. We can instead make detach an explicit operation, parameterised optionally by an executor, and phase out implicit detach on destruction of SemiFuture.

Reviewed By: yfeldblum, andriigrynenko

Differential Revision: D20683652

fbshipit-source-id: 909d2ffcadbe71501edcddbf0847a9cb12aa3cce

Summary:
Migration from Future-returning executor-erasing collectX forms to SemiFuture-returning forms, that are less risky in particular with coroutines.

Earlier changes added collectXSemiFuture and collectXUnsafe as a migration path. This diff changes the behaviour of collectX to return SemiFuture.

Reviewed By: yfeldblum

Differential Revision: D20260537

fbshipit-source-id: 9e01536e4d9af68ff429f9fcd10aea4881d62041

Summary:
Currently `folly/memory/UninitializedMemoryHacks.h`'s `resizeWithoutInitialization()` is able to do its job for `std::vector<T>` and `std::string` only. This PR extends it to support `std::basic_string<T>`.

Effectively, replicated the machinery pattern used to achieve the same for any `std::vector<T>`.

Added test cases too, however the test executable is not being built by the `CMakeLists.txt` (had to enable it locally for testing.)

Is there any particular reason why these tests for `folly/memory/UninitializedMemoryHacks.h` are not built/run by default?
`folly/memory/test/UninitializedMemoryHacksODR.cpp`
`folly/memory/test/UninitializedMemoryHacksTest.cpp`
Pull Request resolved: https://github.com/facebook/folly/pull/1339

Reviewed By: Mizuchi

Differential Revision: D20603510

Pulled By: yfeldblum

fbshipit-source-id: dc92ca71cab6a76e2d93c2bbcb4a325bcd70468c

Summary:
On Windows the build artifacts cannot be easily run directly from the build
output directory without installing them.  The `$PATH` environment variable
needs to be set correctly so that the runtime library dependencies can be
found.

This updates the builder code to emit a `run.ps1` wrapper script in the build
output directory that sets `$PATH` to support running build artifacts directly
from the build directory.

Additionally, this updates the CMake-specific builder to set properly when
running the tests with `ctest`.

Reviewed By: wez

Differential Revision: D20688290

fbshipit-source-id: 5d0f4d685692bca7e37370bd88309cf7634d87f0

Summary:
This still requires support from EdenFS in order to do much
of use, but it takes us a step closer:

* Pull in cpptoml when building with Eden support
* On Windows, when we locate the `.eden` directory, load and parse
  the config file in order to determine the socket path
* If the EdenView constructor throws, treat it as a terminal error
  so that we don't fallback to the regular filesystem watcher.
  This is important because current EdenFS builds don't implement
  the journal thrift API endpoint yet.

Reviewed By: pkaush

Differential Revision: D20504752

fbshipit-source-id: 48bbad49f1641698aa7d7b85674e3ddf4d4e617d

Summary:
We have a global `--install-prefix` argument that can be used to set
the prefix for all projects, but that is only suitable if you are running with
sufficient privileges to install each of the deps to that location during the
build.  Cmake dependency resolution won't work from the build directory in that
situation; it can only see the final installed location and it will error out
if those files are not present, or link against the currently installed version
instead of the version we just built; not great!

This commit adds a project specific `--project-install-prefix` that can be used
on just the leaf project in a set of deps.  That sidesteps the dependency
concern because only the last stage is built in that mode.  This option
can technically be applied to an arbitrary set of projects, but in light
of the above, in practice it only makes sense to use it for the final
cmake project.  Only the CMakeBuilder respects this option.

In the watchman repo, this commit adjusts the autogen.sh script to allow
specifying the installation prefix; it defaults to `/usr/local` as you
might expect.

refs: https://github.com/facebook/watchman/issues/760

Reviewed By: yfeldblum

Differential Revision: D20674439

fbshipit-source-id: 52799dbd47f3c295e2d6469ee2b74cedeaa20138

Summary:
The math that figures out the biggest possible formatted
number, for a stack buffer size, computed 65 bytes for "binary" format:

```
    // #b: 0b prefix + 64 bytes = 65 bytes
```

But with that 2-byte "0b" prefix this of course sums to 66 bytes.

This turns out to be harmless, rather than causing a buffer overrun,
because the buffer size additionally reserves two more bytes for
"prefix shenanigans", which are redundant with the two prefix bytes
explicitly reserved for "0b" (but in this case were covering up the
off-by-one error).

I cleaned up a few things while I was there:

- I fixed the size computation for binary buffers, including
  making it use kMaxBinaryLength, which is based on `sizeof(uintmax_t)`,
  rather than hardcoding `64`.
- I removed the redundant prefix shenanigans reservation.
- I fixed the places that were reserving two bytes for a prefix
  (like "0x") right after asserting that no prefix is allowed,
  e.g. for chars and decimal numbers.
- I stopped reserving a byte for NUL, because these days this code
  uses folly::StringPiece and never NUL-terminates.

Reviewed By: yfeldblum

Differential Revision: D20694395

fbshipit-source-id: 6658675d9993d2fe223675db55c8040ddee143a8

Summary:
Not sure if this is a transient issue, but the URL we've been using to obtain boost has started to return 403 errors.
Switch to a sourceforge download link instead.

Refs: https://github.com/facebook/watchman/pull/797

Reviewed By: chadaustin

Differential Revision: D20739351

fbshipit-source-id: 47483c675d59201a410c9d2a8f6db0f63ea5da69

Summary:
My recent change to ensure that we were using python3 to launch everything failed on windows: the GH actions environment has `python.exe` in the path and it is python version 3.  There is no such thing as `python3` in that environment, although there is a `python2`.

Refs: https://github.com/facebook/watchman/pull/797

Reviewed By: chadaustin

Differential Revision: D20740411

fbshipit-source-id: 0e40590ccedc18e327ebb84901e2509588fdd0ff

Summary:
This diff is a more complete fix for the problem addressed
by D19561643, in which private inheritance caused an incorrect
inaccessibility error for a type that was derived via an alternate
construction from a template param.

Reviewed By: lnicco

Differential Revision: D20718329

fbshipit-source-id: 778d246d07030f6abb9e08e127a98d48c736a7d7

Summary: Upstream range-v3 has changed in accordance with C++20's standard ranges such that view types now need to explicitly opt-in to the `view` concept. This diff adds the hook needed so that the latest version of the range library will recognize `folly::Range` as a view.

Reviewed By: yfeldblum

Differential Revision: D20569727

fbshipit-source-id: 2f8bca017b2f8036b02568997a0b7c76d9c41646

Summary: Fix broken oss build

Reviewed By: simpkins

Differential Revision: D20689035

fbshipit-source-id: 1d287f59fb35cf88482a471dfdf63e89d579e6fc

Summary:
Avoid a forward declaration mismatch between `libiberty.h` and
`libgen.h` that dirs in modular builds (likely related to T35368090).
This defines `HAVE_DECL_BASENAME`, which is normally defined
in the `config.h` generated during the binutils build, to prevent this
conflicting declaration.

Reviewed By: igorsugak

Differential Revision: D20600924

fbshipit-source-id: 0fb6287719abb3cf52d7eda457efbe567985d1d4

Summary: SemiFuture::delayed should pass the SemiFuture all the way through.

Reviewed By: yfeldblum

Differential Revision: D20684503

fbshipit-source-id: e7d1299a177d347cb5b92e9e700c607fc9f7c4c3

Summary: This diff makes it possible to relay on the thrift structures from configerator in OSS.

Reviewed By: ahornby

Differential Revision: D20279457

fbshipit-source-id: 39df1c7a6f78b10a0a5bdeeebe476249ab674cc8

Reviewed By: vitaut

Differential Revision: D20650610

fbshipit-source-id: add9ff42c7c35696767c0c4d004235885fcd1565

Summary:
We are using Folly inside RocksDB, and we noticed a build failure due to cache line sizing on s390x. I fixed it in our copy of Folly, and am sending you the changes upstream.

CC pdillinger
Pull Request resolved: https://github.com/facebook/folly/pull/1340

Reviewed By: WillerZ

Differential Revision: D20628323

Pulled By: Orvid

fbshipit-source-id: 03ea68b023fa1fdf7fae2e283687530ab5b6ead3

Summary: Add signal handling support for the PollIoBackend derived backends

Reviewed By: kevin-vigor

Differential Revision: D20612200

fbshipit-source-id: 5a92e2b46a9fa102bfc02958058679bac6c22269

Summary:
This takes some pressure off both cpu and memory
on a laptop.

Reviewed By: pkaush

Differential Revision: D20562474

fbshipit-source-id: a058c71c47f25c3a2b3c1e34a0d0caf83e642021

Summary:
On linux we didn't account for the `--final-install-prefix` argument
which meant that the binaries would always be rewritten to be relative to
the destdir.

This commit fixes that.

Refs: https://github.com/facebook/watchman/issues/760

(this doesn't deal with the compiled in statedir being in the scratch path though)

Reviewed By: simpkins

Differential Revision: D20659749

fbshipit-source-id: 1e8e198a58361882249c33a67f54a7d97b849257

Summary:
The GH actions defaults for git prevent it from being able
to checkout the fbthrift repo due the length of the java related
files in the fbthrift repo.

This commit tells git to use long filenames and allows the checkout
to succeed.

Reviewed By: fanzeyi

Differential Revision: D20659750

fbshipit-source-id: 060b36d312d52a0769cf2f2dd9af60f7446f94a8

Summary:
Ensure that we are referencing python3 in the paths
that we generate for the github actions workflows, and remove
some shebangs that influence how our internal linters process
the python code.

Reviewed By: fanzeyi

Differential Revision: D20659747

fbshipit-source-id: 6f300f8e91edf7701bb27babc7b1418958cf0a10

Summary: Remove unused files

Reviewed By: yfeldblum

Differential Revision: D20658959

fbshipit-source-id: b387aa4a58ee6a610d71567f5dcd6932e49f7411

Summary: The `|` operation causes the  `int to uint8` conversion warning that be treated as an error on some targets and prevent them use F14Map.

Reviewed By: yfeldblum

Differential Revision: D20654932

fbshipit-source-id: 6c909b7b58f4be263b0e30b1aa3acd82b5b9479d

Summary: We will `std::terminate` if a destructor throws, so it would be better to complain about throwing destructors in the first place.

Reviewed By: nbronson

Differential Revision: D20604722

fbshipit-source-id: d36c771f36d0d0a26f356720698606de628ca747

Summary:
The current implementation of `std::is_nothrow_move_constructible` in libstdc++ implies `std::is_nothrow_destructible`. However, this doesn't seem to be required by the standard, see the notes section of https://en.cppreference.com/w/cpp/types/is_constructible.

Since we know that all Vector and Value sets/maps already satisfy this requirement, let's codify it explicitly.

Reviewed By: nbronson

Differential Revision: D20604544

fbshipit-source-id: bae1e8442585cedb062308b6332bd018cccca2f4

Summary:
F14Node{Map,Set} doesn't require `is_nothrow_destructible<value_type>`.  `clear()` and the destructor are both marked `noexcept`, so they will both terminate if the destructor throws. But `erase()` is not marked `noexcept`, so when the destructor throws during `erase()` the value is left in the map. This could be problematic if the value is half destroyed, or if `eraseInto()` is used.

This diff fixes the problem by marking `destroyItem()` as `noexcept`, so `std::terminate` is called whenever the value destructor throws.

Reviewed By: nbronson

Differential Revision: D20604276

fbshipit-source-id: c52c932d78d6ed61368985a749adf77c27a5a0de

Summary: Add support for non libevent based backends in the AsyncSignalHandler

Reviewed By: kevin-vigor

Differential Revision: D20524116

fbshipit-source-id: fdd49cf75bd51599055239270dd704c496d567e3