Add NSInputStream.source() and BufferedSource.inputStream() functions for Apple's NSInputStream

gradle/libs.versions.toml

@@ -10,6 +10,7 @@ androidx-test-runner = { module = "androidx.test:runner", version = "1.5.2" }
 binaryCompatibilityValidator = { module = "org.jetbrains.kotlinx.binary-compatibility-validator:org.jetbrains.kotlinx.binary-compatibility-validator.gradle.plugin", version = "0.16.3" }
 kotlin-test = { module = "org.jetbrains.kotlin:kotlin-test" }
 kotlin-test-junit = { module = "org.jetbrains.kotlin:kotlin-test-junit" }
+kotlin-coroutines = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version = "1.7.3" }
 kotlin-time = { module = "org.jetbrains.kotlinx:kotlinx-datetime", version = "0.6.1" }
 jmh-gradle-plugin = { module = "me.champeau.jmh:jmh-gradle-plugin", version = "0.7.2" }
 jmh-core = { module = "org.openjdk.jmh:jmh-core", version.ref = "jmh" }

okio/build.gradle.kts

@@ -158,6 +158,11 @@ kotlin {
           nativeTest.dependsOn(nonWasmTest)
           nativeTest.dependsOn(zlibTest)
           createSourceSet("appleTest", parent = nativeTest, children = appleTargets)
+            .apply {
+              dependencies {
+                implementation(libs.kotlin.coroutines)
+              }
+            }
         }
     }
 

okio/src/appleMain/kotlin/okio/ApplePlatform.kt

@@ -0,0 +1,16 @@
+package okio
+
+import kotlinx.cinterop.UnsafeNumber
+import platform.Foundation.NSError
+import platform.Foundation.NSLocalizedDescriptionKey
+import platform.Foundation.NSUnderlyingErrorKey
+
+@OptIn(UnsafeNumber::class)
+internal fun Exception.toNSError() = NSError(
+  domain = "Kotlin",
+  code = 0,
+  userInfo = mapOf(
+    NSLocalizedDescriptionKey to message,
+    NSUnderlyingErrorKey to this,
+  ),
+)

okio/src/appleMain/kotlin/okio/BufferedSink.kt

@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2020 Square, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package okio
+
+import kotlin.experimental.ExperimentalNativeApi
+import kotlin.native.ref.WeakReference
+import kotlinx.cinterop.CPointer
+import kotlinx.cinterop.UnsafeNumber
+import kotlinx.cinterop.convert
+import platform.Foundation.NSError
+import platform.Foundation.NSOutputStream
+import platform.Foundation.NSRunLoop
+import platform.Foundation.NSRunLoopMode
+import platform.Foundation.NSStream
+import platform.Foundation.NSStreamDataWrittenToMemoryStreamKey
+import platform.Foundation.NSStreamDelegateProtocol
+import platform.Foundation.NSStreamEvent
+import platform.Foundation.NSStreamEventErrorOccurred
+import platform.Foundation.NSStreamEventHasSpaceAvailable
+import platform.Foundation.NSStreamEventOpenCompleted
+import platform.Foundation.NSStreamPropertyKey
+import platform.Foundation.NSStreamStatusClosed
+import platform.Foundation.NSStreamStatusError
+import platform.Foundation.NSStreamStatusNotOpen
+import platform.Foundation.NSStreamStatusOpen
+import platform.Foundation.NSStreamStatusOpening
+import platform.Foundation.NSStreamStatusWriting
+import platform.Foundation.performInModes
+import platform.darwin.NSInteger
+import platform.darwin.NSUInteger
+import platform.posix.uint8_tVar
+
+/**
+ * Returns an output stream that writes to this sink. Closing the stream will also close this sink.
+ */
+fun BufferedSink.outputStream(): NSOutputStream = BufferedSinkNSOutputStream(this)
+
+@OptIn(UnsafeNumber::class, ExperimentalNativeApi::class)
+private class BufferedSinkNSOutputStream(
+  private val sink: BufferedSink,
+) : NSOutputStream(toMemory = Unit), NSStreamDelegateProtocol {
+
+  private val isClosed: () -> Boolean = when (sink) {
+    is RealBufferedSink -> sink::closed
+    is Buffer -> {
+      { false }
+    }
+  }
+
+  private var status = NSStreamStatusNotOpen
+  private var error: NSError? = null
+    set(value) {
+      status = NSStreamStatusError
+      field = value
+      postEvent(NSStreamEventErrorOccurred)
+      sink.close()
+    }
+
+  override fun streamStatus() = if (status != NSStreamStatusError && isClosed()) NSStreamStatusClosed else status
+
+  override fun streamError() = error
+
+  override fun open() {
+    if (status == NSStreamStatusNotOpen) {
+      status = NSStreamStatusOpening
+      status = NSStreamStatusOpen
+      postEvent(NSStreamEventOpenCompleted)
+      postEvent(NSStreamEventHasSpaceAvailable)
+    }
+  }
+
+  override fun close() {
+    if (status == NSStreamStatusError || status == NSStreamStatusNotOpen) return
+    status = NSStreamStatusClosed
+    runLoop = null
+    runLoopModes = listOf()
+    sink.close()
+  }
+
+  override fun write(buffer: CPointer<uint8_tVar>?, maxLength: NSUInteger): NSInteger {
+    if (streamStatus != NSStreamStatusOpen || buffer == null) return -1
+    status = NSStreamStatusWriting
+    val toWrite = minOf(maxLength, Int.MAX_VALUE.convert()).toInt()
+    return try {
+      sink.buffer.write(buffer, toWrite)
+      sink.emitCompleteSegments()
+      status = NSStreamStatusOpen
+      toWrite.convert()
+    } catch (e: Exception) {
+      error = e.toNSError()
+      -1
+    }
+  }
+
+  override fun hasSpaceAvailable() = !isFinished
+
+  private val isFinished
+    get() = when (streamStatus) {
+      NSStreamStatusClosed, NSStreamStatusError -> true
+      else -> false
+    }
+
+  override fun propertyForKey(key: NSStreamPropertyKey): Any? = when (key) {
+    NSStreamDataWrittenToMemoryStreamKey -> sink.buffer.snapshotAsNSData()
+    else -> null
+  }
+
+  override fun setProperty(property: Any?, forKey: NSStreamPropertyKey) = false
+
+  // WeakReference as delegate should not be retained
+  // https://developer.apple.com/documentation/foundation/nsstream/1418423-delegate
+  private var _delegate: WeakReference<NSStreamDelegateProtocol>? = null
+  private var runLoop: NSRunLoop? = null
+  private var runLoopModes = listOf<NSRunLoopMode>()
+
+  private fun postEvent(event: NSStreamEvent) {
+    val runLoop = runLoop ?: return
+    runLoop.performInModes(runLoopModes) {
+      if (runLoop == this.runLoop) {
+        delegateOrSelf.stream(this, event)
+      }
+    }
+  }
+
+  override fun delegate() = _delegate?.value
+
+  private val delegateOrSelf get() = delegate ?: this
+
+  override fun setDelegate(delegate: NSStreamDelegateProtocol?) {
+    _delegate = delegate?.let { WeakReference(it) }
+  }
+
+  override fun stream(aStream: NSStream, handleEvent: NSStreamEvent) {
+    // no-op
+  }
+
+  override fun scheduleInRunLoop(aRunLoop: NSRunLoop, forMode: NSRunLoopMode) {
+    if (runLoop == null) {
+      runLoop = aRunLoop
+    }
+    if (runLoop == aRunLoop) {
+      runLoopModes += forMode
+    }
+    if (status == NSStreamStatusOpen) {
+      postEvent(NSStreamEventHasSpaceAvailable)
+    }
+  }
+
+  override fun removeFromRunLoop(aRunLoop: NSRunLoop, forMode: NSRunLoopMode) {
+    if (aRunLoop == runLoop) {
+      runLoopModes -= forMode
+      if (runLoopModes.isEmpty()) {
+        runLoop = null
+      }
+    }
+  }
+
+  override fun description() = "$sink.outputStream()"
+}