| commit | e20fe888fabc1fc995dc61180e8a31b5f809a95f | [log] [tgz] |
|---|---|---|
| author | Abseil Team <absl-team@google.com> | Thu Apr 15 19:42:51 2021 -0700 |
| committer | Dino Radaković <dinor@google.com> | Thu Apr 15 19:45:30 2021 -0700 |
| tree | 5877907889fe35eb3162aa71111e16bd1d59fde4 | |
| parent | 46dfbfe31ca1dd414e4c33cbcbcd7199bb4efde3 [diff] |
Export of internal Abseil changes -- 341670bce317dd6af8d3c066970230591a47e80c by Martijn Vels <mvels@google.com>: Change GetStack() and GetParentStack() to return absl::Span PiperOrigin-RevId: 368765721 -- 6aaab9536d6957303c7aba100c3afaa6fb0ea2c8 by Martijn Vels <mvels@google.com>: Remove locking from parent stack. This change removes the need to lock all access to `parent_stack' by making the 'copy constructor' logic specify the 'copied from' CordzInfo (where available) to the TrackCord function, after which parent_stack is immutable. PiperOrigin-RevId: 368760630 -- b19e2059cada35a8ede994833018edac94de6ddc by Martijn Vels <mvels@google.com>: Add cordz instrumentation to Cord PiperOrigin-RevId: 368746225 -- 67b8bbf980f0f4e1db79aa32968e9a715a09b51a by Martijn Vels <mvels@google.com>: Create ABSL_INTERNAL_CORDZ_ENABLED define controlling when Cordz code is enabled There are specific builds and condtions under which we don't support cordz sampling, which is per this change represented by ABSL_INTERNAL_CORDZ_ENABLED being defined. PiperOrigin-RevId: 368731603 -- 8cbfe0e3169637a620f4b66ad2bc2ce340879cb0 by Martijn Vels <mvels@google.com>: Add a `rep` property to CordzInfo to be managed by Cord logic. This change adds a `rep` property to CordzInfo, which is intended to be used by collection logic. Mini design: Cord invokes TrackCord() providing the active 'root' cordrep of the newly sampled Cord, returning a CordzInfo with a weak (uncounted) reference to this root. Cord invokes `SetCordRep()` each time the root cordrep of the sampled Cord is updated while holding `mutex()`. Cord must also obtain `mutex()` _before_ removing a reference on the old root. i.e.: Cord must guarantee that the (weak) reference held in CordzInfo is at all times valid. CordzInfo collection code can then safely obtain a (reference counted) rep pointer by adding a reference to `rep_` while holding `mutex()`. This requires only a very brief critical section inside CordzInfo logic, minimizing contention with concurrent Cord updates. Cord code should typically obtain and hold `mutex()` for the entirety of each mutating Cord operation on a sampled cord. As Cord is thread compatible, it never competes on the lock with any other thread. The only possible concurrent access is from Cordz collection code, which should be a relatively rare event. PiperOrigin-RevId: 368673758 -- 1255120dce2bdd6b4205a34a0e555e0b74b6152f by Martijn Vels <mvels@google.com>: Remove 'depth' from active recorded metrics. Going forward we do not 'live' record depth (and size), but will observe these at collection time only. PiperOrigin-RevId: 368636572 -- 83e5146e35f221736b49e9f0a8805f8c159a51db by Martijn Vels <mvels@google.com>: Make cordz targets visible in OSS PiperOrigin-RevId: 368615010 -- dcb16a4f1239151f0a8c70a8cfeb29dabbd113b8 by Martijn Vels <mvels@google.com>: Internal cleanup PiperOrigin-RevId: 368514666 GitOrigin-RevId: 341670bce317dd6af8d3c066970230591a47e80c Change-Id: I94cecfbbd441eb386f99fc5186c468a7a5538862
The repository contains the Abseil C++ library code. Abseil is an open-source collection of C++ code (compliant to C++11) designed to augment the C++ standard library.
Abseil is an open-source collection of C++ library code designed to augment the C++ standard library. The Abseil library code is collected from Google's own C++ code base, has been extensively tested and used in production, and is the same code we depend on in our daily coding lives.
In some cases, Abseil provides pieces missing from the C++ standard; in others, Abseil provides alternatives to the standard for special needs we've found through usage in the Google code base. We denote those cases clearly within the library code we provide you.
Abseil is not meant to be a competitor to the standard library; we've just found that many of these utilities serve a purpose within our code base, and we now want to provide those resources to the C++ community as a whole.
If you want to just get started, make sure you at least run through the Abseil Quickstart. The Quickstart contains information about setting up your development environment, downloading the Abseil code, running tests, and getting a simple binary working.
Bazel and CMake are the official build systems for Abseil.
See the quickstart for more information on building Abseil using the Bazel build system.
If you require CMake support, please check the CMake build instructions and CMake Quickstart.
Abseil is officially supported on many platforms. See the Abseil platform support guide for details on supported operating systems, compilers, CPUs, etc.
Abseil contains the following C++ library components:
base Abseil Fundamentals base library contains initialization code and other code which all other Abseil code depends on. Code within base may not depend on any other code (other than the C++ standard library).algorithm algorithm library contains additions to the C++ <algorithm> library and container-based versions of such algorithms.cleanup cleanup library contains the control-flow-construct-like type absl::Cleanup which is used for executing a callback on scope exit.container container library contains additional STL-style containers, including Abseil's unordered “Swiss table” containers.debugging debugging library contains code useful for enabling leak checks, and stacktrace and symbolization utilities.hash hash library contains the hashing framework and default hash functor implementations for hashable types in Abseil.memory memory library contains C++11-compatible versions of std::make_unique() and related memory management facilities.meta meta library contains C++11-compatible versions of type checks available within C++14 and C++17 versions of the C++ <type_traits> library.numeric numeric library contains C++11-compatible 128-bit integers.status status contains abstractions for error handling, specifically absl::Status and absl::StatusOr<T>.strings strings library contains a variety of strings routines and utilities, including a C++11-compatible version of the C++17 std::string_view type.synchronization synchronization library contains concurrency primitives (Abseil's absl::Mutex class, an alternative to std::mutex) and a variety of synchronization abstractions.time time library contains abstractions for computing with absolute points in time, durations of time, and formatting and parsing time within time zones.types types library contains non-container utility types, like a C++11-compatible version of the C++17 std::optional type.utility utility library contains utility and helper code.Abseil recommends users “live-at-head” (update to the latest commit from the master branch as often as possible). However, we realize this philosophy doesn't work for every project, so we also provide Long Term Support Releases to which we backport fixes for severe bugs. See our release management document for more details.
The Abseil C++ library is licensed under the terms of the Apache license. See LICENSE for more information.
For more information about Abseil: