commit | 9a62f27d1fe53552b0838156c17adc3b68dcc585 | [log] [tgz] |
---|---|---|
author | dkhalanskyjb <52952525+dkhalanskyjb@users.noreply.github.com> | Tue Sep 03 16:43:23 2019 +0300 |
committer | Roman Elizarov <elizarov@gmail.com> | Tue Sep 03 16:43:23 2019 +0300 |
tree | 7acf4b89cca4def92dced93a24e9daa45f372ee3 | |
parent | 57cc36454da6851ecd2a00abe7cfd6ee6e06928f [diff] |
Fix of a bug in the semaphore (#1477) * Add a failing test for a semaphore This test consistently fails for the current implementation. It attempts to cause the following state: after `job2` increments `availablePermits` but before it wakes up the acquirer in the queue, the acquirer is cancelled. Then, regardless of whether `RESUMED` or `CANCELLED` was written first, another cell in the queue is marked to be resumed. However, this is incorrect: on cancellation, the acquirer incremented the number of available permits once more, making it `1`; thus, at the same time there exist two permits for acquiring the mutex. At the next loop iteration, a new acquirer tries to claim ownership of the mutex and succeeds because it goes to the thread queue and sees its cell as `RESUMED`. Thus, two entities own a mutex at the same time. * Fix a bug in semaphore implementation The fix works as follows: if `availablePermits` is negative, its absolute value denotes the logical length of the thread queue. Increasing its value if it was negative means that this thread promises to wake exactly one thread, and if its positive, returns one permit to the semaphore itself. Before, the error was in that a queue could be of negative length: if it consisted of only `N` cells, and `N` resume queries arrived, cancelling any threads would mean that there are more wakers then there are sleepers, which breaks the invariants of the semaphore. Thus, if on cancellation the acquirer detects that it leaves the queue empty in the presence of resumers, it simply transfers the semaphore acquisition permit to the semaphore itself, because it knows that it, in a sense, owns it already: there is a thread that is bound to resume this cell.
Library support for Kotlin coroutines with multiplatform support. This is a companion version for Kotlin 1.3.50
release.
suspend fun main() = coroutineScope { launch { delay(1000) println("Kotlin Coroutines World!") } println("Hello") }
Play with coroutines online here
Promise
via Promise.await and promise builder;Window
via Window.asCoroutineDispatcher, etc.The libraries are published to kotlinx bintray repository, linked to JCenter and pushed to Maven Central.
Add dependencies (you can also add other modules that you need):
<dependency> <groupId>org.jetbrains.kotlinx</groupId> <artifactId>kotlinx-coroutines-core</artifactId> <version>1.3.0</version> </dependency>
And make sure that you use the latest Kotlin version:
<properties> <kotlin.version>1.3.50</kotlin.version> </properties>
Add dependencies (you can also add other modules that you need):
dependencies { implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0' }
And make sure that you use the latest Kotlin version:
buildscript { ext.kotlin_version = '1.3.50' }
Make sure that you have either jcenter()
or mavenCentral()
in the list of repositories:
repository { jcenter() }
Add dependencies (you can also add other modules that you need):
dependencies { implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.3.0") }
And make sure that you use the latest Kotlin version:
plugins { kotlin("jvm") version "1.3.50" }
Make sure that you have either jcenter()
or mavenCentral()
in the list of repositories.
Core modules of kotlinx.coroutines
are also available for Kotlin/JS and Kotlin/Native. In common code that should get compiled for different platforms, add dependency tokotlinx-coroutines-core-common
(follow the link to get the dependency declaration snippet).
Add kotlinx-coroutines-android
module as dependency when using kotlinx.coroutines
on Android:
implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.0'
This gives you access to Android Dispatchers.Main coroutine dispatcher and also makes sure that in case of crashed coroutine with unhandled exception this exception is logged before crashing Android application, similarly to the way uncaught exceptions in threads are handled by Android runtime.
For R8 no actions required, it will take obfuscation rules from the jar.
For Proguard you need to add options from coroutines.pro to your rules manually.
R8 is a replacement for ProGuard in Android ecosystem, it is enabled by default since Android gradle plugin 3.4.0 (3.3.0-beta also had it enabled).
Kotlin/JS version of kotlinx.coroutines
is published as kotlinx-coroutines-core-js
(follow the link to get the dependency declaration snippet).
You can also use kotlinx-coroutines-core
package via NPM.
Kotlin/Native version of kotlinx.coroutines
is published as kotlinx-coroutines-core-native
(follow the link to get the dependency declaration snippet).
Only single-threaded code (JS-style) on Kotlin/Native is currently supported. Kotlin/Native supports only Gradle version 4.10 and you need to enable Gradle metadata in your settings.gradle
file:
enableFeaturePreview('GRADLE_METADATA')
Since Kotlin/Native does not generally provide binary compatibility between versions, you should use the same version of Kotlin/Native compiler as was used to build kotlinx.coroutines
.
This library is built with Gradle. To build it, use ./gradlew build
. You can import this project into IDEA, but you have to delegate build actions to Gradle (in Preferences -> Build, Execution, Deployment -> Build Tools -> Gradle -> Runner)
JAVA_HOME
environment variable.JDK_16
environment variable. It is okay to have JDK_16
pointing to JAVA_HOME
for external contributions.All development (both new features and bug fixes) is performed in develop
branch. This way master
sources always contain sources of the most recently released version. Please send PRs with bug fixes to develop
branch. Fixes to documentation in markdown files are an exception to this rule. They are updated directly in master
.
The develop
branch is pushed to master
during release.