Extend filesystem support (#213)

* Added FileSystem interface providing basic operations on paths: reading/writing files, creating directories, moving and deleting files and directories, and gathering fs node metadata.
* Provided default FileSystem implementation - SystemFileSystem
* Extended Path API to allow getting parent paths and constructing children's paths using platform-dependent APIs under the hood.
* Added API to get path to the system temporary directory

Closes: #206 #211 #212 #183 #214

---------

Co-authored-by: Jeff Lockhart <[email protected]>

build-logic/src/main/kotlin/kotlinx/io/conventions/kotlinx-io-multiplatform.gradle.kts

@@ -60,13 +60,35 @@ kotlin {
 
     configureNativePlatforms()
 
-    val nativeTargets = nativeTargets()
     val appleTargets = appleTargets()
+    val mingwTargets = mingwTargets()
+
+    /*
+      Native source sets hierarchy:
+      native
+      |-> apple
+      |-> nonApple
+          |-> mingw
+          |-> unix
+              |-> linux
+              |-> android
+     */
+
     sourceSets {
-        val nativeMain = createSourceSet("nativeMain", parent = commonMain.get(), children = nativeTargets)
-        val nativeTest = createSourceSet("nativeTest", parent = commonTest.get(), children = nativeTargets)
+        val nativeMain = createSourceSet("nativeMain", parent = commonMain.get())
+        val nativeTest = createSourceSet("nativeTest", parent = commonTest.get())
+        val nonAppleMain = createSourceSet("nonAppleMain", parent = nativeMain)
+        val nonAppleTest = createSourceSet("nonAppleTest", parent = nativeTest)
         createSourceSet("appleMain", parent = nativeMain, children = appleTargets)
         createSourceSet("appleTest", parent = nativeTest, children = appleTargets)
+        createSourceSet("mingwMain", parent = nonAppleMain, children = mingwTargets)
+        createSourceSet("mingwTest", parent = nonAppleTest, children = mingwTargets)
+        val unixMain = createSourceSet("unixMain", parent = nonAppleMain)
+        val unixTest = createSourceSet("unixTest", parent = nonAppleTest)
+        createSourceSet("linuxMain", parent = unixMain, children = linuxTargets())
+        createSourceSet("linuxTest", parent = unixTest, children = linuxTargets())
+        createSourceSet("androidMain", parent = unixMain, children = androidTargets())
+        createSourceSet("androidTest", parent = unixTest, children = androidTargets())
     }
 }
 
@@ -137,10 +159,6 @@ fun KotlinMultiplatformExtension.configureNativePlatforms() {
     mingwX64()
 }
 
-fun nativeTargets(): List<String> {
-    return linuxTargets() + mingwTargets() + androidTargets()
-}
-
 fun appleTargets() = listOf(
     "iosArm64",
     "iosX64",

core/android/src/files/FileSystemAndroid.kt

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE.txt file.
+ */
+
+package kotlinx.io.files
+
+import kotlinx.cinterop.ExperimentalForeignApi
+import kotlinx.cinterop.toKString
+import platform.posix.__posix_basename
+import platform.posix.dirname
+
+@OptIn(ExperimentalForeignApi::class)
+internal actual fun dirnameImpl(path: String): String {
+    return dirname(path)?.toKString() ?: ""
+}
+
+@OptIn(ExperimentalForeignApi::class)
+internal actual fun basenameImpl(path: String): String {
+    return __posix_basename(path)?.toKString() ?: ""
+}
+
+internal actual fun isAbsoluteImpl(path: String): Boolean = path.startsWith('/')

core/api/kotlinx-io-core.api

@@ -195,12 +195,53 @@ public final class kotlinx/io/Utf8Kt {
 	public static synthetic fun writeString$default (Lkotlinx/io/Sink;Ljava/lang/String;IIILjava/lang/Object;)V
 }
 
+public final class kotlinx/io/files/FileMetadata {
+	public fun <init> ()V
+	public fun <init> (ZZJ)V
+	public synthetic fun <init> (ZZJILkotlin/jvm/internal/DefaultConstructorMarker;)V
+	public final fun getSize ()J
+	public final fun isDirectory ()Z
+	public final fun isRegularFile ()Z
+}
+
+public abstract interface class kotlinx/io/files/FileSystem {
+	public abstract fun atomicMove (Lkotlinx/io/files/Path;Lkotlinx/io/files/Path;)V
+	public abstract fun createDirectories (Lkotlinx/io/files/Path;Z)V
+	public static synthetic fun createDirectories$default (Lkotlinx/io/files/FileSystem;Lkotlinx/io/files/Path;ZILjava/lang/Object;)V
+	public abstract fun delete (Lkotlinx/io/files/Path;Z)V
+	public static synthetic fun delete$default (Lkotlinx/io/files/FileSystem;Lkotlinx/io/files/Path;ZILjava/lang/Object;)V
+	public abstract fun exists (Lkotlinx/io/files/Path;)Z
+	public abstract fun metadataOrNull (Lkotlinx/io/files/Path;)Lkotlinx/io/files/FileMetadata;
+	public abstract fun sink (Lkotlinx/io/files/Path;Z)Lkotlinx/io/RawSink;
+	public static synthetic fun sink$default (Lkotlinx/io/files/FileSystem;Lkotlinx/io/files/Path;ZILjava/lang/Object;)Lkotlinx/io/RawSink;
+	public abstract fun source (Lkotlinx/io/files/Path;)Lkotlinx/io/RawSource;
+}
+
+public final class kotlinx/io/files/FileSystemJvmKt {
+	public static final field SystemFileSystem Lkotlinx/io/files/FileSystem;
+	public static final field SystemTemporaryDirectory Lkotlinx/io/files/Path;
+}
+
 public final class kotlinx/io/files/Path {
+	public fun equals (Ljava/lang/Object;)Z
+	public final fun getName ()Ljava/lang/String;
+	public final fun getParent ()Lkotlinx/io/files/Path;
+	public fun hashCode ()I
+	public final fun isAbsolute ()Z
+	public fun toString ()Ljava/lang/String;
 }
 
-public final class kotlinx/io/files/PathsKt {
+public final class kotlinx/io/files/PathsJvmKt {
+	public static final field SystemPathSeparator C
 	public static final fun Path (Ljava/lang/String;)Lkotlinx/io/files/Path;
 	public static final fun sink (Lkotlinx/io/files/Path;)Lkotlinx/io/Sink;
 	public static final fun source (Lkotlinx/io/files/Path;)Lkotlinx/io/Source;
 }
 
+public final class kotlinx/io/files/PathsKt {
+	public static final fun Path (Ljava/lang/String;[Ljava/lang/String;)Lkotlinx/io/files/Path;
+	public static final fun Path (Lkotlinx/io/files/Path;[Ljava/lang/String;)Lkotlinx/io/files/Path;
+	public static final fun sinkDeprecated (Lkotlinx/io/files/Path;)Lkotlinx/io/Sink;
+	public static final fun sourceDeprecated (Lkotlinx/io/files/Path;)Lkotlinx/io/Source;
+}
+

core/apple/src/files/FileSystemApple.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE.txt file.
+ */
+@file:OptIn(ExperimentalForeignApi::class)
+
+package kotlinx.io.files
+
+import kotlinx.cinterop.ExperimentalForeignApi
+import kotlinx.cinterop.cstr
+import kotlinx.cinterop.memScoped
+import kotlinx.cinterop.toKString
+import kotlinx.io.IOException
+import platform.Foundation.NSTemporaryDirectory
+import platform.posix.*
+
+
+internal actual fun atomicMoveImpl(source: Path, destination: Path) {
+    if (rename(source.path, destination.path) != 0) {
+        throw IOException("Move failed: ${strerror(errno)?.toKString()}")
+    }
+}
+
+public actual val SystemTemporaryDirectory: Path
+    get() = Path(NSTemporaryDirectory())
+
+internal actual fun dirnameImpl(path: String): String {
+    memScoped {
+        return dirname(path.cstr.ptr)?.toKString() ?: ""
+    }
+}
+
+internal actual fun basenameImpl(path: String): String {
+    memScoped {
+        return basename(path.cstr.ptr)?.toKString() ?: ""
+    }
+}
+
+internal actual fun isAbsoluteImpl(path: String): Boolean = path.startsWith('/')
+
+internal actual fun mkdirImpl(path: String) {
+    if (mkdir(path, PermissionAllowAll) != 0) {
+        throw IOException("mkdir failed: ${strerror(errno)?.toKString()}")
+    }
+}

core/apple/test/NSInputStreamSourceTest.kt

@@ -6,11 +6,9 @@
 package kotlinx.io
 
 import kotlinx.io.files.Path
-import kotlinx.io.files.sink
+import kotlinx.io.files.SystemFileSystem
 import platform.Foundation.NSInputStream
-import platform.Foundation.NSTemporaryDirectory
 import platform.Foundation.NSURL
-import platform.Foundation.NSUUID
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
@@ -28,11 +26,9 @@ class NSInputStreamSourceTest {
     @OptIn(ExperimentalStdlibApi::class)
     @Test
     fun nsInputStreamSourceFromFile() {
-        // can be replaced with createTempFile() when #183 is fixed
-        // https://github.com/Kotlin/kotlinx-io/issues/183
-        val file = "${NSTemporaryDirectory()}${NSUUID().UUIDString()}"
+        val file = tempFileName()
         try {
-            Path(file).sink().use {
+            SystemFileSystem.sink(Path(file)).buffered().use {
                 it.writeString("example")
             }
 
@@ -42,7 +38,7 @@ class NSInputStreamSourceTest {
             assertEquals(7, source.readAtMostTo(buffer, 10))
             assertEquals("example", buffer.readString())
         } finally {
-            deleteFile(file)
+            SystemFileSystem.delete(Path(file))
         }
     }
 

core/build.gradle.kts

@@ -72,3 +72,7 @@ tasks.withType<DokkaTaskPartial>().configureEach {
         )
     }
 }
+
+animalsniffer {
+    annotation = "kotlinx.io.files.AnimalSnifferIgnore"
+}

core/common/src/-CommonPlatform.kt

@@ -23,10 +23,16 @@ package kotlinx.io
 
 internal expect fun String.asUtf8ToByteArray(): ByteArray
 
+/**
+ * Signals about a general issue occurred during I/O operation.
+ */
 public expect open class IOException(message: String?, cause: Throwable?) : Exception {
     public constructor(message: String? = null)
 }
 
+/**
+ * Signals that the end of the file or stream was reached unexpectedly during an input operation.
+ */
 public expect open class EOFException(message: String? = null) : IOException
 
 
@@ -35,4 +41,4 @@ public expect open class EOFException(message: String? = null) : IOException
 // This is a workaround that should be removed as soon as stdlib will support AutoCloseable
 // actual typealias on JVM.
 @OptIn(ExperimentalStdlibApi::class)
-internal typealias AutoCloseableAlias = AutoCloseable
+internal typealias AutoCloseableAlias = AutoCloseable