0.3.2 released, readme update

# Conflicts:
#	build.gradle.kts

.gitignore

@@ -5,3 +5,6 @@
 /gradle/wrapper/gradle-wrapper.properties
 /node_modules
 .kotlin
+/.gigaide/gigaide.properties
+/java_pid40366.hprof
+/local.properties

README.md

@@ -4,16 +4,15 @@ Multiplatform binary tools collection, including portable serialization of the c
 many useful tools to work with binary data, like CRC family checksums, dumps, etc. It works well also in the browser and
 in native targets.
 
-# Recent changes
+# Important note
 
-- 0.1.6 add many useful features, added support to wasmJS and all other platforms. Note to wasmJS: it appears to be a bug in wasm compiler so BipackDecoder could cause wasm loading problem.
+Currently published version 0.3.2 for all platform is fully compatible with breaking kotlinx.datetime/kotlin.time migration as of Kotlin 2.2.21 and is __a recommended version to use__.
 
-- 0.1.1: added serialized KVStorage with handy implementation on JVM and JS platforms and some required synchronization
+Sorry for inconveniences, it is all caused by strange ideas of the Kotlin team.
-  tools.
--
-- 0.1.0: uses modern kotlin 1.9.*, fixes problem with singleton or empty/object serialization
 
-The last 1.8-based version is 0.0.8. Some fixes are not yet backported to it pls leave an issue of needed.
+# Documentation
+
+Aside of the samples in this readme please see [library documentation](https://code.sergeych.net/docs/mp_bintools/).
 
 # Usage
 
@@ -31,7 +30,7 @@ And add dependency to the proper place in your project like this:
 ```kotlin
 dependencies {
     // ...
-    implementation("net.sergeych:mp_bintools:0.1.0")
+    implementation("net.sergeych:mp_bintools:0.1.12")
 }
 ```
 

build.gradle.kts

@@ -1,31 +1,29 @@
+import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
+
 plugins {
-    kotlin("multiplatform") version "2.0.0"
+    kotlin("multiplatform") version "2.2.21"
-    kotlin("plugin.serialization") version "2.0.0"
+    kotlin("plugin.serialization") version "2.2.21"
     id("org.jetbrains.dokka") version "1.9.20"
+    id("com.android.library") version "8.7.2"
     `maven-publish`
 }
 
-val serialization_version = "1.6.5-SNAPSHOT"
-
 group = "net.sergeych"
-version = "0.1.6"
+version = "0.3.2"
 
 repositories {
+    google()
     mavenCentral()
     mavenLocal()
     maven("https://maven.universablockchain.com/")
 }
 
 kotlin {
-    jvmToolchain(8)
+    jvmToolchain(17)
-    jvm {
+    jvm()
-//        compilations.all {
+    androidTarget() {
-//            kotlinOptions.jvmTarget = "1.8"
+        // Ensure Android variant is published to Maven so consumers get androidMain APIs
-//        }
+        publishLibraryVariants("release")
-        withJava()
-        testRuns["test"].executionTask.configure {
-            useJUnitPlatform()
-        }
     }
     js {
       browser()
@@ -39,8 +37,8 @@ kotlin {
     iosSimulatorArm64()
     linuxX64()
     linuxArm64()
-    mingwX64()
 
+    @OptIn(ExperimentalWasmDsl::class)
     wasmJs {
         browser()
         binaries.executable()
@@ -58,14 +56,15 @@ kotlin {
             languageSettings.optIn("kotlinx.serialization.ExperimentalSerializationApi")
             languageSettings.optIn("kotlin.ExperimentalUnsignedTypes")
             languageSettings.optIn("kotlin.contracts.ExperimentalContracts")
+            languageSettings.optIn("kotlin.time.ExperimentalTime")
         }
         val commonMain by getting {
             dependencies {
-                implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.8.1")
+                implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.10.2")
                 // this is actually a bug: we need only the core, but bare core causes strange errors
-                implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3")
+                implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.9.0")
-                api("net.sergeych:mp_stools:[1.4.7,)")
+                api("net.sergeych:mp_stools:[1.6.3,)")
-                implementation("org.jetbrains.kotlinx:kotlinx-datetime:0.5.0")
+                implementation("org.jetbrains.kotlinx:kotlinx-datetime:0.7.1")
             }
         }
         val nativeMain by creating {
@@ -83,10 +82,17 @@ kotlin {
         val commonTest by getting {
             dependencies {
                 implementation(kotlin("test"))
+                implementation("org.jetbrains.kotlinx:kotlinx-coroutines-test:1.9.0")
+
             }
         }
         val jvmMain by getting
         val jvmTest by getting
+        val androidMain by getting {
+            dependencies {
+                // Android base64 and preferences are in the SDK; no extra deps required
+            }
+        }
         val jsMain by getting {
             dependencies {
             }
@@ -95,29 +101,53 @@ kotlin {
 //        val nativeTest by getting
         val wasmJsMain by getting {
             dependencies {
+                implementation("org.jetbrains.kotlinx:kotlinx-browser-wasm-js:0.5.0")
+            }
+        }
+        val wasmJsTest by getting {
+            dependencies {
+//                implementation("org.jetbrains.kotlinx:kotlinx-browser:0.3")
             }
         }
-        val wasmJsTest by getting
     }
+}
 
+publishing {
+    val mavenToken by lazy {
+        File("${System.getProperty("user.home")}/.gitea_token").readText()
+    }
+    repositories {
+        maven {
+            credentials(HttpHeaderCredentials::class) {
+                name = "Authorization"
+                value = mavenToken
+            }
+            url = uri("https://gitea.sergeych.net/api/packages/SergeychWorks/maven")
+            authentication {
+                create("Authorization", HttpHeaderAuthentication::class)
+            }
+        }
+    }
+}
+
+android {
+    namespace = "net.sergeych.bintools"
+    compileSdk = 34
+    defaultConfig {
+        minSdk = 21
+    }
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+    // Publish only release variant of the Android target so consumers (Android apps)
+    // resolve the platform artifact instead of common metadata, which is required
+    // to access Android-only APIs like net.sergeych.bintools.AndroidKV
     publishing {
-        val mavenToken by lazy {
+        singleVariant("release") {
-            File("${System.getProperty("user.home")}/.gitea_token").readText()
+            withSourcesJar()
-        }
-        repositories {
-            maven {
-                credentials(HttpHeaderCredentials::class) {
-                    name = "Authorization"
-                    value = mavenToken
-                }
-                url = uri("https://gitea.sergeych.net/api/packages/SergeychWorks/maven")
-                authentication {
-                    create("Authorization", HttpHeaderAuthentication::class)
-                }
-            }
         }
     }
-
 }
 
 tasks.dokkaHtml.configure {

gradle.properties

@@ -1,2 +1,8 @@
 kotlin.code.style=official
-kotlin.js.compiler=ir
+kotlin.mpp.applyDefaultHierarchyTemplate=false
+
+org.gradle.parallel=true
+org.gradle.jvmargs=-Xmx4096M -Dfile.encoding=UTF-8
+org.gradle.configuration-cache=true
+org.gradle.caching=true
+

gradlew

@@ -55,7 +55,7 @@
 #       Darwin, MinGW, and NonStop.
 #
 #   (3) This script is generated from the Groovy template
-#       https://github.com/gradle/gradle/blob/HEAD/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
 #       within the Gradle project.
 #
 #       You can find Gradle at https://github.com/gradle/gradle/.
@@ -80,11 +80,13 @@ do
     esac
 done
 
-# This is normally unused
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
-# shellcheck disable=SC2034
+
+APP_NAME="Gradle"
 APP_BASE_NAME=${0##*/}
-# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+
-APP_HOME=$( cd "${APP_HOME:-./}" > /dev/null && pwd -P ) || exit
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
 
 # Use the maximum available, or set MAX_FD != -1 to use that value.
 MAX_FD=maximum
@@ -131,29 +133,22 @@ location of your Java installation."
     fi
 else
     JAVACMD=java
-    if ! command -v java >/dev/null 2>&1
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
-    then
-        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
 
 Please set the JAVA_HOME variable in your environment to match the
 location of your Java installation."
-    fi
 fi
 
 # Increase the maximum file descriptors if we can.
 if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
     case $MAX_FD in #(
       max*)
-        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC2039,SC3045
         MAX_FD=$( ulimit -H -n ) ||
             warn "Could not query maximum file descriptor limit"
     esac
     case $MAX_FD in  #(
       '' | soft) :;; #(
       *)
-        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
-        # shellcheck disable=SC2039,SC3045
         ulimit -n "$MAX_FD" ||
             warn "Could not set maximum file descriptor limit to $MAX_FD"
     esac
@@ -198,15 +193,11 @@ if "$cygwin" || "$msys" ; then
     done
 fi
 
-
+# Collect all arguments for the java command;
-# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
-DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+#     shell script including quotes and variable substitutions, so put them in
-
+#     double quotes to make sure that they get re-expanded; and
-# Collect all arguments for the java command:
+#   * put everything else in single quotes, so that it's not re-expanded.
-#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
-#     and any embedded shellness will be escaped.
-#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
-#     treated as '${Hostname}' itself on the command line.
 
 set -- \
         "-Dorg.gradle.appname=$APP_BASE_NAME" \
@@ -214,12 +205,6 @@ set -- \
         org.gradle.wrapper.GradleWrapperMain \
         "$@"
 
-# Stop when "xargs" is not available.
-if ! command -v xargs >/dev/null 2>&1
-then
-    die "xargs is not available"
-fi
-
 # Use "xargs" to parse quoted args.
 #
 # With -n1 it outputs one arg per line, with the quotes and backslashes removed.

gradlew.bat

@@ -14,7 +14,7 @@
 @rem limitations under the License.
 @rem
 
-@if "%DEBUG%"=="" @echo off
+@if "%DEBUG%" == "" @echo off
 @rem ##########################################################################
 @rem
 @rem  Gradle startup script for Windows
@@ -25,8 +25,7 @@
 if "%OS%"=="Windows_NT" setlocal
 
 set DIRNAME=%~dp0
-if "%DIRNAME%"=="" set DIRNAME=.
+if "%DIRNAME%" == "" set DIRNAME=.
-@rem This is normally unused
 set APP_BASE_NAME=%~n0
 set APP_HOME=%DIRNAME%
 
@@ -41,7 +40,7 @@ if defined JAVA_HOME goto findJavaFromJavaHome
 
 set JAVA_EXE=java.exe
 %JAVA_EXE% -version >NUL 2>&1
-if %ERRORLEVEL% equ 0 goto execute
+if "%ERRORLEVEL%" == "0" goto execute
 
 echo.
 echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
@@ -76,15 +75,13 @@ set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
 
 :end
 @rem End local scope for the variables with windows NT shell
-if %ERRORLEVEL% equ 0 goto mainEnd
+if "%ERRORLEVEL%"=="0" goto mainEnd
 
 :fail
 rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
 rem the _cmd.exe /c_ return code!
-set EXIT_CODE=%ERRORLEVEL%
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
-if %EXIT_CODE% equ 0 set EXIT_CODE=1
+exit /b 1
-if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
-exit /b %EXIT_CODE%
 
 :mainEnd
 if "%OS%"=="Windows_NT" endlocal

settings.gradle.kts

@@ -1,3 +1,21 @@
 
+pluginManagement {
+    repositories {
+        google()
+        gradlePluginPortal()
+        mavenCentral()
+        mavenLocal()
+    }
+}
+
+dependencyResolutionManagement {
+    repositories {
+        google()
+        mavenCentral()
+        mavenLocal()
+        maven("https://maven.universablockchain.com/")
+    }
+}
+
 rootProject.name = "mp_bintools"
 

src/androidMain/kotlin/net.sergeych.bintools/KVStorage.android.kt

@@ -0,0 +1,65 @@
+package net.sergeych.bintools
+
+import android.content.Context
+import android.content.SharedPreferences
+import net.sergeych.bintools.AndroidKV.init
+import net.sergeych.mp_tools.decodeBase64Compact
+import net.sergeych.mp_tools.encodeToBase64Compact
+
+/**
+ * Simple holder to provide Application [Context] for this library.
+ *
+ * Call [init] from your app (e.g., in `Application.onCreate`) before using
+ * [defaultNamedStorage].
+ */
+object AndroidKV {
+    @Volatile
+    private var appContext: Context? = null
+
+    fun init(context: Context) {
+        appContext = context.applicationContext
+    }
+
+    internal fun requireContext(): Context =
+        appContext ?: error("AndroidKV is not initialized. Call AndroidKV.init(applicationContext) first.")
+}
+
+/**
+ * Implementation of [KVStorage] backed by [SharedPreferences].
+ * Values are stored as base64-encoded strings to fit preferences capabilities.
+ */
+class SharedPreferencesKVStorage(
+    private val prefs: SharedPreferences,
+    keyPrefix: String = ""
+) : KVStorage {
+    private val prefix = if (keyPrefix.isEmpty()) "" else "$keyPrefix:"
+
+    private fun k(key: String) = "$prefix$key"
+
+    override fun get(key: String): ByteArray? =
+        prefs.getString(k(key), null)?.decodeBase64Compact()
+
+    override fun set(key: String, value: ByteArray?) {
+        val e = prefs.edit()
+        val kk = k(key)
+        if (value == null) e.remove(kk)
+        else e.putString(kk, value.encodeToBase64Compact())
+        e.apply()
+    }
+
+    override val keys: Set<String>
+        get() {
+            val allKeys = prefs.all.keys
+            if (prefix.isEmpty()) return allKeys
+            return allKeys.filter { it.startsWith(prefix) }
+                .map { it.removePrefix(prefix) }
+                .toSet()
+        }
+}
+
+actual fun defaultNamedStorage(name: String): KVStorage {
+    val ctx = AndroidKV.requireContext()
+    val prefs = ctx.getSharedPreferences(name, Context.MODE_PRIVATE)
+    // We use separate preferences file per name, so prefix can be empty
+    return SharedPreferencesKVStorage(prefs)
+}

src/androidMain/kotlin/net/sergeych/synctools/ProtectedOp.android.kt

@@ -0,0 +1,17 @@
+package net.sergeych.synctools
+
+import java.util.concurrent.locks.ReentrantLock
+
+/**
+ * Android actual implementation mirrors JVM using [ReentrantLock].
+ */
+actual fun ProtectedOp(): ProtectedOpImplementation = object : ProtectedOpImplementation {
+    private val access = ReentrantLock()
+    override fun lock() {
+        access.lock()
+    }
+
+    override fun unlock() {
+        access.unlock()
+    }
+}

src/androidMain/kotlin/net/sergeych/synctools/WaitHandle.android.kt

@@ -0,0 +1,22 @@
+package net.sergeych.synctools
+
+@Suppress("EXPECT_ACTUAL_CLASSIFIERS_ARE_IN_BETA_WARNING")
+actual class WaitHandle {
+    @Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
+    private val access = Object()
+
+    actual fun await(milliseconds: Long): Boolean {
+        return synchronized(access) {
+            try {
+                access.wait(milliseconds)
+                true
+            } catch (_: InterruptedException) {
+                false
+            }
+        }
+    }
+
+    actual fun wakeUp() {
+        synchronized(access) { access.notifyAll() }
+    }
+}

src/commonMain/kotlin/net.sergeych.bintools/ByteChunk.kt

@@ -0,0 +1,98 @@
+package net.sergeych.bintools
+
+import kotlinx.serialization.Serializable
+import net.sergeych.mp_tools.encodeToBase64Url
+import kotlin.math.min
+import kotlin.random.Random
+
+/**
+ * Bytes sequence with comparison, concatenation, and string representation,
+ * could be used as hash keys for pure binary values, etc.
+ */
+@Suppress("unused")
+@Serializable
+class ByteChunk(val data: UByteArray): Comparable<ByteChunk> {
+
+    val size: Int get() = data.size
+
+    /**
+     * Per-byte comparison also of different length. From two chunks
+     * of different size but equal beginning, the shorter is considered
+     * the smaller.
+     */
+    override fun compareTo(other: ByteChunk): Int {
+        val limit = min(size, other.size)
+        for( i in 0 ..< limit) {
+            val own = data[i]
+            val their = other.data[i]
+            if( own < their) return -1
+            else if( own > their) return 1
+        }
+        if( size < other.size ) return -1
+        if( size > other.size ) return 1
+        return 0
+    }
+
+    /**
+     * Equal chunks means content equality.
+     */
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is ByteChunk) return false
+
+        return data contentEquals other.data
+    }
+
+    /**
+     * Content-based hash code
+     */
+    override fun hashCode(): Int {
+        return data.contentHashCode()
+    }
+
+    /**
+     * hex representation of data
+     */
+    override fun toString(): String = base64
+
+    /**
+     * Hex encoded data
+     */
+    val hex by lazy { data.encodeToHex() }
+
+    /**
+     * human-readable dump
+     */
+    val dump by lazy { data.toDump() }
+
+    /**
+     * Lazy encode to base64 with url alphabet, without trailing fill '=' characters.
+     */
+    val base64 by lazy { data.asByteArray().encodeToBase64Url() }
+
+    /**
+     * Lazy (cached) view of [data] as ByteArray
+     */
+    val asByteArray: ByteArray by lazy { data.asByteArray() }
+
+    /**
+     * Concatenate two chunks and return new one
+     */
+    operator fun plus(other: ByteChunk): ByteChunk = ByteChunk(data + other.data)
+
+    companion object {
+        fun fromHex(hex: String): ByteChunk = ByteChunk(hex.decodeHex().asUByteArray())
+        fun random(size: Int=16): ByteChunk = Random.nextBytes(size).asChunk()
+    }
+}
+
+/**
+ * Create the representation of this array as ByteChunk; it does not copy the data.
+ */
+fun ByteArray.asChunk() = ByteChunk(this.asUByteArray())
+
+/**
+ * Create the representation of this array as ByteChunk; it does not copy the data.
+ */
+@Suppress("unused")
+fun UByteArray.asChunk() = ByteChunk(this)

src/commonMain/kotlin/net.sergeych.bintools/DataKVStorage.kt

@@ -2,11 +2,18 @@ package net.sergeych.bintools
 
 import net.sergeych.bipack.BipackDecoder
 import net.sergeych.bipack.BipackEncoder
+import net.sergeych.mp_logger.LogTag
+import net.sergeych.mp_logger.Loggable
+import net.sergeych.mp_logger.debug
+import net.sergeych.synctools.AtomicCounter
 import net.sergeych.synctools.ProtectedOp
 import net.sergeych.synctools.WaitHandle
 import net.sergeych.synctools.withLock
 
-class DataKVStorage(private val provider: DataProvider) : KVStorage {
+private val ac = AtomicCounter(0)
+
+class DataKVStorage(private val provider: DataProvider) : KVStorage,
+    Loggable by LogTag("DKVS${ac.incrementAndGet()}") {
 
     data class Lock(val name: String) {
         private val exclusive = ProtectedOp()
@@ -20,8 +27,6 @@ class DataKVStorage(private val provider: DataProvider) : KVStorage {
                 exclusive.withLock {
                     if (readerCount == 0) {
                         return f()
-                    } else {
-                        println("can't lock $this: count is $readerCount")
                     }
                 }
                 pulses.await()
@@ -49,19 +54,16 @@ class DataKVStorage(private val provider: DataProvider) : KVStorage {
         access.withLock {
             // TODO: read keys
             for (fn in provider.list()) {
-                println("Scanning: $fn")
+                debug { "Scanning: $fn" }
                 if (fn.endsWith(".d")) {
                     val id = fn.dropLast(2).toInt(16)
-                    println("found data record: $fn -> $id")
+                    debug  { "found data record: $fn -> $id" }
-
                     val name = provider.read(fn) { BipackDecoder.decode<String>(it) }
-                    println("Key=$name")
                     keyIds[name] = id
                     if (id > lastId) lastId = id
-                } else println("ignoring record $fn")
+                } else debug { "ignoring record $fn" }
             }
         }
-        println("initialized, ${keyIds.size} records found, lastId=$lastId")
     }
 
 
@@ -97,7 +99,7 @@ class DataKVStorage(private val provider: DataProvider) : KVStorage {
         lock.lockExclusive { provider.write(recordName(id), f) }
     }
 
-    fun deleteEntry(name: String) {
+    private fun deleteEntry(name: String) {
         // fast pre-check:
         if (name !in keyIds) return
         // global lock: we can't now detect concurrent delete + write ops, so exclusive:

src/commonMain/kotlin/net.sergeych.bintools/KVStorage.kt

@@ -1,11 +1,10 @@
 package net.sergeych.bintools
 
+import kotlinx.serialization.KSerializer
 import kotlinx.serialization.serializer
 import net.sergeych.bipack.BipackDecoder
 import net.sergeych.bipack.BipackEncoder
 import kotlin.reflect.KProperty
-import kotlin.reflect.KType
-import kotlin.reflect.typeOf
 
 
 /**
@@ -43,7 +42,7 @@ interface KVStorage {
      * Default implementation uses [keys]. You may override it for performance
      */
     fun clear() {
-        for (k in keys) this[k] = null
+        for (k in keys.toList()) this[k] = null
     }
 
     /**
@@ -93,48 +92,50 @@ inline fun <reified T:Any>KVStorage.read(key: String): T? =
 @Suppress("unused")
 inline fun <reified T:Any>KVStorage.load(key: String): T? = read(key)
 
-inline operator fun <reified T> KVStorage.invoke(defaultValue: T,overrideName: String? = null) =
+inline operator fun <reified T: Any> KVStorage.invoke(defaultValue: T,overrideName: String? = null) =
-    KVStorageDelegate<T>(this, typeOf<T>(), defaultValue, overrideName)
+    KVStorageDelegate(this, serializer<T>(), defaultValue, overrideName)
 
-inline fun <reified T> KVStorage.stored(defaultValue: T, overrideName: String? = null) =
+inline fun <reified T: Any> KVStorage.stored(defaultValue: T, overrideName: String? = null) =
-    KVStorageDelegate<T>(this, typeOf<T>(), defaultValue, overrideName)
+    KVStorageDelegate(this, serializer<T>(), defaultValue, overrideName)
 
-inline fun <reified T> KVStorage.optStored(overrideName: String? = null) =
+inline fun <reified T: Any> KVStorage.optStored(overrideName: String? = null) =
-    KVStorageDelegate<T?>(this, typeOf<T?>(), null, overrideName)
+    KVStorageOptDelegate<T>(this, serializer<T>(),overrideName)
 
-class KVStorageDelegate<T>(
+class KVStorageDelegate<T: Any>(
     private val storage: KVStorage,
-    type: KType,
+    private val serializer: KSerializer<T>,
     private val defaultValue: T,
     private val overrideName: String? = null,
 ) {
-
     private fun name(property: KProperty<*>): String = overrideName ?: property.name
 
-    private var cachedValue: T = defaultValue
+    operator fun getValue(thisRef: Any?, property: KProperty<*>): T =
-    private var cacheReady = false
+        storage.get(name(property))?.let { BipackDecoder.decode(serializer, it) }
-    private val serializer = serializer(type)
+            ?: defaultValue
 
-    @Suppress("UNCHECKED_CAST")
-    operator fun getValue(thisRef: Any?, property: KProperty<*>): T {
-        if (cacheReady) return cachedValue
-        val data = storage.get(name(property))
-        println("Got data: ${data?.toDump()}")
-        if (data == null)
-            cachedValue = defaultValue
-        else
-            cachedValue = BipackDecoder.decode(data.toDataSource(), serializer) as T
-        cacheReady = true
-        return cachedValue
-    }
 
     operator fun setValue(thisRef: Any?, property: KProperty<*>, value: T) {
-//        if (!cacheReady || value != cachedValue) {
+        storage[name(property)] = BipackEncoder.encode(serializer, value)
-            cachedValue = value
+    }
-            cacheReady = true
+}
-            println("set ${name(property)} to ${BipackEncoder.encode(serializer, value).toDump()}")
+
+class KVStorageOptDelegate<T: Any>(
+    private val storage: KVStorage,
+    private val serializer: KSerializer<T>,
+    private val overrideName: String? = null,
+) {
+    private fun name(property: KProperty<*>): String = overrideName ?: property.name
+
+    operator fun getValue(thisRef: Any?, property: KProperty<*>): T? =
+        storage.get(name(property))?.let{
+            BipackDecoder.decode(serializer, it)
+        }
+
+    operator fun setValue(thisRef: Any?, property: KProperty<*>, value: T?) {
+        if (value == null)
+            storage.delete(name(property))
+        else
             storage[name(property)] = BipackEncoder.encode(serializer, value)
-//        }
     }
 }
 
@@ -217,7 +218,19 @@ class MemoryKVStorage(copyFrom: KVStorage? = null) : KVStorage {
  *    - otherwise, the folder will be created in "`~/.local_storage`" parent directory
  *      (which also will be created if needed).
  *
- *  - For the native platorms it is not yet implemented (but will be soon).
+ *  - In Android (new!) it is implemented using preferences, but initializing is needed in
+ *      main activity `onCreate`, somewhat like:
+ *  ```kotlin
+ *       override fun onCreate(savedInstanceState: Bundle?) {
+ *          super.onCreate(savedInstanceState)
+ *          // set the Context which Preferences will be used for
+ *          // defaultNamedStorage
+ *          net.sergeych.bintools.AndroidKV.init(this)
+ *     }
+ *  ```
+ *  see also `AndroidKV` and `SharedPreferencesKVStorage` for Android
+ *
+ *  - For the native platforms it is not yet implemented (but will be soon).
  *
  *  See [DataKVStorage] and [DataProvider] to implement a KVStorage on filesystems and like,
  *  and `FileDataProvider` class on JVM target.

src/commonMain/kotlin/net.sergeych.bintools/MRUCache.kt

@@ -8,6 +8,7 @@ package net.sergeych.bintools
  *
  * Note that the cost, [MRUCache] is slower than [MutableMap].
  */
+@Deprecated("moved to net.sergeych.collections", ReplaceWith("net.sergeych.collections.MRUCache"))
 class MRUCache<K,V>(val maxSize: Int,
                     private val cache: LinkedHashMap<K,V> = LinkedHashMap()
 ): MutableMap<K,V> by cache {

src/commonMain/kotlin/net.sergeych.bintools/simple_codecs.kt

@@ -84,13 +84,11 @@ private val hexDigits = "0123456789ABCDEF"
 
 fun Long.encodeToHex(length: Int = 0): String {
     var result = ""
-    var value = this
+    var value = this.toULong()
-    val end = if( value >= 0 ) 0L else -1L
-//    if (value < 0) throw IllegalArgumentException("cant convert to hex negative (ambiguous)")
     do {
-        result = hexDigits[(value and 0x0f).toInt()] + result
+        result = hexDigits[(value and 0x0fu).toInt()] + result
         value = value shr 4
-    } while (value != end)
+    } while (value != 0UL)
     while (result.length < length) result = "0" + result
     return result
 }
@@ -113,6 +111,8 @@ fun Collection<Byte>.encodeToHex(separator: String = " "): String = joinToString
 
 fun ByteArray.toDump(wide: Boolean = false): String = toDumpLines(wide).joinToString("\n")
 
+fun UByteArray.toDump(wide: Boolean = false): String = asByteArray().toDumpLines(wide).joinToString("\n")
+
 fun ByteArray.toDumpLines(wide: Boolean = false): List<String> {
 
     val lineSize = if (wide) 32 else 16

src/commonMain/kotlin/net.sergeych.bipack/BipackDecoder.kt

@@ -1,6 +1,5 @@
 package net.sergeych.bipack
 
-import kotlinx.datetime.Instant
 import kotlinx.serialization.DeserializationStrategy
 import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.KSerializer
@@ -12,6 +11,7 @@ import kotlinx.serialization.modules.EmptySerializersModule
 import kotlinx.serialization.modules.SerializersModule
 import kotlinx.serialization.serializer
 import net.sergeych.bintools.*
+import kotlin.time.Instant
 
 /**
  * Decode BiPack format. Note that it relies on [DataSource] so can throw [DataSource.EndOfData]
@@ -74,7 +74,7 @@ class BipackDecoder(
     }
 
     override fun <T> decodeSerializableValue(deserializer: DeserializationStrategy<T>): T {
-        return if (deserializer == Instant.serializer())
+        return if (deserializer == serializer<Instant>())
             Instant.fromEpochMilliseconds(decodeLong()) as T
         else
             super.decodeSerializableValue(deserializer)

src/commonMain/kotlin/net.sergeych.bipack/BipackEncoder.kt

@@ -1,6 +1,5 @@
 package net.sergeych.bipack
 
-import kotlinx.datetime.Instant
 import kotlinx.serialization.SerializationStrategy
 import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.encoding.AbstractEncoder
@@ -9,6 +8,7 @@ import kotlinx.serialization.modules.EmptySerializersModule
 import kotlinx.serialization.modules.SerializersModule
 import kotlinx.serialization.serializer
 import net.sergeych.bintools.*
+import kotlin.time.Instant
 
 class BipackEncoder(val output: DataSink) : AbstractEncoder() {
 

src/commonMain/kotlin/net.sergeych.bipack/annotations.kt

@@ -3,22 +3,19 @@ package net.sergeych.bipack
 import kotlinx.serialization.SerialInfo
 
 /**
- * If this annotation is presented in some @Serializable class definition, its instances
+ * To be used with [kotlinx.serialization.Serializable]. Allows serialized classes to be
- * will be serialized with the leading number of fields. This allows extending class later
+ * extended by _adding members with default initializers_ __to the end of the constructor list__.
- * providing new parameters __to the end of the class__ and _with default values__.
  *
- * __IMPORTANT NOTE__. Since version 0.0.7 it's been also possible to use default values
+ * This annotation makes Bipack to insert fields count before the
- * for non-serialized fields after the end-of-data. If the source reports it correctly, e.g.
+ * serialized data. It then checks it on deserializing to fill not serialized fields will
- * [net.sergeych.bintools.DataSource.isEnd] returns true, the unset fields are initialized
+ * default values.
- * with default value. This approach ___is not working when the loading instance is not the last
- * in the deciding array!___, still it is useful to decode isolated objects. We recommend to
- * use [Extendable] where needed and possible.
  *
- * Whe deserializing such instances from previous version binaries, the new parameters
+ * Note that since 0.0.7 the same behavior could be achieved by serializing each instance in the
- * will get default values.
+ * array as Bipack correctly processes end-of-data by filling missing fields with default values,
+ * using `Extendable` is more convenient and save some space, most of the time.
  *
- * Serialized data of classes not market as ExtendableFormat could not be changed without
+ * _Please note that without this annotation it could be impossible to deserialize old versions of
- * breaking compatibility with existing serialized data.
+ * the class, in particular, in array, inner fields, etc._
  */
 @Target(AnnotationTarget.CLASS)
 @SerialInfo

src/commonMain/kotlin/net/sergeych/collections/BitSet.kt

@@ -0,0 +1,342 @@
+package net.sergeych.collections
+
+import kotlinx.serialization.Serializable
+import net.sergeych.bintools.encodeToHex
+import net.sergeych.collections.BitSet.Companion.MAX_VALUE
+
+/**
+ * Bitset is a serializable set of __positive__ integers represented as bits in long array.
+ * This ought to be more effective, and sure it is more effective in serialized form,
+ * as long as maximum stored number is not too big, We recommend limit of 10-20k.
+ *
+ * It limits hold values to [MAX_VALUE] anyway to avoid fast memory depletion
+ *
+ * It has optimized bitwise operation based versions of [retainAll] and [removeAll],
+ * [intersect] and [isEmpty], that are used if their arguments, where used, are `BitSet`
+ * instances. Also [equals] works faster with BitSet and BitSet.
+ *
+ * Use [bitSetOf] and [bitSetOfEnum] to simply create bitsets.
+ *
+ * It also contains syntax sugar to work with enums directly:
+ *
+ * - [includes] and [includesAll] to check that enum is in set
+ * - [insert], [insertAll], [delete], and [deleteAll] to manipulate enum values
+ * - [toEnumSet] to convert to set of enums
+ *
+ */
+@Serializable
+class BitSet(private val bits: MutableList<Long> = mutableListOf()) : MutableSet<Int> {
+
+    fun set(element: Int, value: Boolean = true) = setBit(element, value)
+
+    fun clear(element: Int) = set(element, false)
+
+    operator fun plusAssign(element: Int) {
+        set(element)
+    }
+
+    operator fun plus(element: Int): BitSet = BitSet(bits.toMutableList()).apply { set(element) }
+
+    operator fun minusAssign(element: Int) {
+        clear(element)
+    }
+
+    operator fun minus(element: Int): BitSet = BitSet(bits.toMutableList()).apply { clear(element) }
+
+    private fun setBit(element: Int, value: Boolean): Boolean {
+        require(element >= 0, { "only positive numbers are allowed" })
+        require(element < MAX_VALUE, { "maximum value allowed is $MAX_VALUE" })
+        val offset = element shr 6
+        val bit = element % 64
+        return if (value) {
+            while (offset >= bits.size) bits.add(0)
+            val last = bits[offset] and masks[bit]
+            bits[offset] = bits[offset] or masks[bit]
+            last != 0L
+        } else {
+            if (offset < bits.size) {
+                // bigger, not existing means 0
+                val last = bits[offset] and masks[bit]
+                bits[offset] = bits[offset] and maskNot[bit]
+                last != 0L
+            } else {
+                // already 0: index not in bits:
+                false
+            }
+        }
+    }
+
+    private fun getBit(value: Int): Boolean {
+        val offset = value shr 6
+        if (offset >= bits.size) return false
+        val bit = value % 64
+        return (bits[offset] and masks[bit]) != 0L
+    }
+
+    override fun add(element: Int): Boolean = setBit(element, true)
+
+    override val size: Int
+        get() {
+            var count = 0
+            for (w in bits) {
+                for (m in masks) {
+                    if ((w and m) != 0L) count++
+                }
+            }
+            return count
+        }
+
+    override fun addAll(elements: Collection<Int>): Boolean {
+        var added = false
+        for (i in elements) if (setBit(i, true)) added = true
+        return added
+
+    }
+
+    override fun clear() {
+        bits.clear()
+    }
+
+    override fun isEmpty(): Boolean {
+        if (bits.isEmpty()) return true
+        for (w in bits) if (w != 0L) return false
+        return true
+    }
+
+    fun toList(): List<Int> {
+        var value = 0
+        val result = mutableListOf<Int>()
+        for (w in bits) {
+            for (m in masks) {
+                if ((w and m) != 0L) result += value
+                value++
+            }
+        }
+        return result
+    }
+
+    fun toHex(): String = bits.toString() + " " + bits.joinToString(" ") { it.encodeToHex() }
+
+    override fun iterator(): MutableIterator<Int> = object : MutableIterator<Int> {
+        private val i = toList().iterator()
+        private var last: Int? = null
+        override operator fun hasNext() = i.hasNext()
+        override fun next(): Int = i.next().also { last = it }
+        override fun remove() {
+            last?.let { clear(it) } ?: IllegalStateException("hasNext() was not called")
+        }
+    }
+
+    private fun fastRetainAll(elements: BitSet): Boolean {
+        var result = false
+        for (i in bits.indices) {
+            if (i < elements.bits.size) {
+                val x = bits[i]
+                val y = x and elements.bits[i]
+                if (x != y) {
+                    result = true
+                    bits[i] = y
+                }
+            } else {
+                if (bits[i] != 0L) {
+                    bits[i] = 0
+                    result = true
+                }
+            }
+        }
+        return result
+    }
+
+    override fun retainAll(elements: Collection<Int>): Boolean {
+        return if (elements is BitSet)
+            fastRetainAll(elements)
+        else {
+            var value = 0
+            var result = false
+            for ((i, _w) in bits.withIndex()) {
+                var w = _w
+                for (m in masks) {
+                    if ((w and m) != 0L && value !in elements) {
+                        w = w and m.inv()
+                        bits[i] = w
+                        result = true
+                    }
+                    value++
+                }
+            }
+            result
+        }
+    }
+
+    override fun removeAll(elements: Collection<Int>): Boolean {
+        return if (elements is BitSet)
+            fastRemoveAll(elements)
+        else {
+            var value = 0
+            var result = false
+            for ((i, _w) in bits.withIndex()) {
+                var w = _w
+                for (m in masks) {
+                    if ((w and m) != 0L && value in elements) {
+                        w = w and m.inv()
+                        bits[i] = w
+                        result = true
+                    }
+                    value++
+                }
+            }
+            result
+        }
+    }
+
+    private fun fastRemoveAll(elements: BitSet): Boolean {
+        var result = false
+        for (i in bits.indices) {
+            if (i < elements.bits.size) {
+                val x = bits[i]
+                val y = x and elements.bits[i].inv()
+                if (x != y) {
+                    bits[i] = y
+                    result = true
+                }
+            }
+        }
+        println("fast2")
+        return result
+    }
+
+    override fun remove(element: Int): Boolean = setBit(element, false)
+
+    override fun containsAll(elements: Collection<Int>): Boolean {
+        for (e in elements) if (e !in this) return false
+        return true
+    }
+
+    fun toIntSet() = toList().toSet()
+
+    override fun contains(element: Int): Boolean = getBit(element)
+
+    /**
+     * Check that this set contains and ordinal of a given enum element.
+     */
+    infix fun <E> includes(element: E)
+            where E : Enum<*> = contains(element.ordinal)
+
+    /**
+     * Check that this set contains all elements using its ordinals.
+     */
+    infix fun <E> includesAll(elements: Collection<E>)
+            where E : Enum<*> = elements.all { it.ordinal in this }
+
+    fun intersect(other: Iterable<Int>): BitSet {
+        val result = toBitSet()
+        result.retainAll(other)
+        println("I: $this /\\ $other = $result")
+        return result
+    }
+
+    override fun toString(): String {
+        return toList().toString()
+    }
+
+    /**
+     * Checks that this set contains at least one element with ordinal
+     */
+    infix inline fun <reified E> includesAny(elements: Collection<E>): Boolean
+            where E : Enum<E> {
+        val ords = elements.map { it.ordinal }.toBitSet()
+        return !ords.intersect(this).isEmpty()
+    }
+
+    /**
+     * Create an independent copy of this bitset
+     */
+    fun toBitSet() = BitSet(bits.toMutableList())
+
+    inline fun <reified T> toEnumSet(): Set<T>
+            where T : Enum<T> {
+        val values = enumValues<T>()
+        val result = mutableSetOf<T>()
+        for (i in this) result += values[i]
+        return result
+    }
+
+    /**
+     * Insert an element of an enum by its ordinal, much like [add].
+     *
+     * @return `true` if the element has actually been added, `false` if
+     *          BitSet was not modified.
+     */
+    fun <E> insert(element: E): Boolean
+            where E : Enum<*> = add(element.ordinal)
+
+    /**
+     * Remove an element of an enum using its ordinal, much like [remove].
+     *
+     * @return `true` if the element has actually been removed, `false` if
+     *          BitSet was not modified.
+     */
+    fun <E> delete(element: E): Boolean
+            where E : Enum<*> = remove(element.ordinal)
+
+    /**
+     * Insert all elements using its ordinals, much like [addAll].
+     *
+     * @return `true` if at lease one element has actually been added, `false`
+     *          if BitSet was not modified.
+     */
+    fun <E> insertAll(element: Collection<E>): Boolean
+            where E : Enum<*> = addAll(element.map { it.ordinal })
+
+    /**
+     * Remove all the elements using its ordinals, much like [removeAll].
+     *
+     * @return `true` if at least one element has actually been removed, `false` if
+     *          BitSet was not modified.
+     */
+    fun <E> deleteAll(elements: Collection<E>): Boolean
+            where E : Enum<*> = removeAll(elements.map { it.ordinal })
+
+    /**
+     * Reduces storage size trying to compact storage. It might free some memory, depending
+     * on the platform implementation of lists and contents. Does not change stored values.
+     */
+    fun compact() {
+       while( bits.isNotEmpty() && bits.last() == 0L ) bits.removeLast()
+    }
+
+    override fun hashCode(): Int = bits.hashCode()
+
+    override fun equals(other: Any?): Boolean {
+        if( other is BitSet ) {
+            compact(); other.compact()
+            return other.bits == this.bits
+        }
+        return toIntSet().equals(
+            if( other is Set<*>) other
+            else (other as Collection<*>).toSet()
+        )
+    }
+
+
+    companion object {
+        val masks = Array(64) { (1L shl it) }
+        val maskNot = masks.map { it.inv() }.toLongArray()
+
+        // limit size to ≈ 100kb
+        const val MAX_VALUE = 8_388_106
+    }
+}
+
+fun bitSetOf(vararg values: Int) = BitSet().apply {
+    for (i in values) add(i)
+}
+
+fun <E : Enum<*>> bitSetOfEnum(vararg values: E) =
+    BitSet().also {
+        for (v in values) it.add(v.ordinal)
+    }
+
+
+fun Iterable<Int>.toBitSet(): BitSet = BitSet().also { it.addAll(this) }
+fun IntArray.toBitSet(): BitSet = BitSet().also { it.addAll(this.asIterable()) }

src/commonMain/kotlin/net/sergeych/collections/ExpirableAsyncCache.kt

@@ -0,0 +1,168 @@
+package net.sergeych.collections
+
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import net.sergeych.mptools.withReentrantLock
+import kotlin.time.Clock
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.seconds
+import kotlin.time.Instant
+
+/**
+ * MRU cache with expiration, with safe async concurrent access.
+ *
+ * Expired items are removed when accessing the map, when reading values or when putting
+ * it when [maxCapacity] is reached. See note about freeing resources below.
+ *
+ * It is much like [Map] and [MutableMap], but using suspend functions now limit usage of
+ * operator functions so we are not implementing it. Also, modification with [entries] is
+ * not allowed.
+ *
+ * Unlike [MRUCache], it drops expired values. Removing expired item is lazy, actual resource
+ * freeing could be delayed. To force actual removal use [cleanup].
+ *
+ * @param lifeTime how long the value should be kept
+ * @param maxCapacity if set, limits the capacity. Least Recent Used elements would be dropped
+ *      to fit this parameter.
+ * @param onItemRemoved called when some item is removed for any reason (e.g. expiration or overwriting).
+ *      Note that this call also suspends put variants until done
+ */
+class ExpirableAsyncCache<K, V>(
+    val lifeTime: Duration = 30.seconds,
+    val maxCapacity: Int? = null,
+    val onItemRemoved: (suspend (V) -> Unit)? = null
+) {
+
+    class Slot<V>(
+        var value: V,
+        var lastUsedAt: Instant = Clock.System.now(),
+    )
+
+    private val access = Mutex()
+
+    private val cache = mutableMapOf<K, Slot<V>>()
+
+    suspend fun get(key: K): V? {
+        return access.withReentrantLock {
+            cache.get(key)?.let {
+                val now = Clock.System.now()
+                println("lifetime $key: ${now - it.lastUsedAt}")
+                if (now - it.lastUsedAt > lifeTime) {
+                    cache.remove(key)
+                    onItemRemoved?.invoke(it.value)
+                    null
+                } else {
+                    it.lastUsedAt = now
+                    it.value
+                }
+            }
+        }
+    }
+
+    /**
+     * Put the value for key. Calls [onItemRemoved] if needed.
+     * @return previous value or null
+     */
+    suspend fun put(key: K, value: V): V? {
+        // insert may replace existing item, so we do it first:
+        return access.withLock {
+            cache[key]?.let {
+                if (value != it.value)
+                    onItemRemoved?.invoke(it.value)
+                val oldValue = it.value
+                it.value = value
+                it.lastUsedAt = Clock.System.now()
+                oldValue
+            } ?: run {
+                // overflow could be caused by put, so put first
+                cache.put(key, Slot(value))
+                // now check size
+                fixSize()
+                null
+            }
+        }
+    }
+
+    private suspend fun fixSize() {
+        maxCapacity?.let {
+            if (it >= cache.size) {
+                cache.remove(cache.minBy { it.value.lastUsedAt }.key)
+                    ?.also { onItemRemoved?.invoke(it.value) }
+                    ?.value
+            }
+        }
+    }
+
+    /**
+     * Remove all expired elements. This function is not needed unless you
+     * want to free resources associated with expired elements immediately.
+     *
+     * [onItemRemoved] is called for each removed item before returning.
+     */
+    @Suppress("unused")
+    suspend fun cleanup() {
+        access.withLock {
+            val d = Clock.System.now()
+            for( e in cache.entries.toList()) {
+                if( d - e.value.lastUsedAt > lifeTime )
+                    cache.remove(e.key)
+            }
+        }
+    }
+
+    suspend fun getOrDefault(key: K, value: V): V = get(key) ?: value
+
+    /**
+     * Atomically get or put value to the cache.
+     *
+     * If there is expired existing value, [onItemRemoved] will be called for it
+     * before assigning new value.
+     */
+    suspend fun getOrPut(key: K, defaultValue: suspend () -> V): V {
+        return access.withLock {
+            cache[key]?.let {
+                if( Clock.System.now() - it.lastUsedAt > lifeTime) {
+                    onItemRemoved?.invoke(it.value)
+                }
+                it.lastUsedAt = Clock.System.now()
+                it.value
+            } ?: run {
+                val v = defaultValue()
+                cache[key] = Slot(v)
+                fixSize()
+                v
+            }
+        }
+    }
+
+    data class Entry<K, V>(override val key: K, override val value: V) : Map.Entry<K, V>
+
+    val entries: Set<Map.Entry<K, V>>
+        get() = cache.entries.map { Entry(it.key, it.value.value) }.toSet()
+
+    val keys: Set<K>
+        get() = cache.keys
+
+    val size: Int
+        get() = cache.size
+
+    @Suppress("unused")
+    val values: Collection<V>
+        get() = cache.values.map { it.value }
+
+    @Suppress("unused")
+    fun isEmpty(): Boolean = cache.isEmpty()
+
+    @Suppress("unused")
+    fun containsValue(value: V): Boolean {
+        for (v in cache.values)
+            if (v.value == value) return true
+        return false
+    }
+
+    @Suppress("unused")
+    fun containsKey(key: K): Boolean = key in cache
+
+    operator fun contains(k: K): Boolean = k in cache
+}
+

src/commonMain/kotlin/net/sergeych/collections/MRUCache.kt

@@ -0,0 +1,64 @@
+package net.sergeych.collections
+
+/**
+ * Most Recently Used keys Cache.
+ * Maintains the specified size, removed least used elements on insertion. Element usage is
+ * when it is inserted, updated or accessed (with [get]). Least recently used (LRU) keys
+ * are automatically removed to maintain the [maxSize].
+ *
+ * Note that the cost, [MRUCache] is slower than [MutableMap].
+ */
+class MRUCache<K,V>(val maxSize: Int,
+                    private val cache: LinkedHashMap<K,V> = LinkedHashMap()
+): MutableMap<K,V> by cache {
+
+    private fun checkSize() {
+        while(cache.size > maxSize) {
+            cache.remove(cache.keys.first())
+        }
+    }
+
+    /**
+     * Put the [value] associated with [key] which becomes MRU whether it existed in the cache or was added now.
+     *
+     * If [size] == [maxSize] LRU key will be dropped.
+     *
+     * @return old value for the [key] or null
+     */
+    override fun put(key: K, value: V): V? {
+        // we need it to become MRU, so we remove it to clear its position
+        val oldValue = cache.remove(key)
+        // now we always add, not update, so it will become MRU element:
+        cache.put(key,value).also { checkSize() }
+        return oldValue
+    }
+
+    /**
+     * Put all the key-value pairs, this is exactly same as calling [put] in the same
+     * order. Note that is the [from] map is not linked and its size is greater than
+     * [maxSize], some unpredictable keys will not be added. To be exact, only last
+     * [maxSize] keys will be added by the order providing by [from] map entries
+     * enumerator.
+     *
+     * If from is [LinkedHashMap] or like, onl
+     */
+    override fun putAll(from: Map<out K, V>) {
+        // maybe we should optimize it not to add unnecessary first keys
+        for( e in from) {
+            put(e.key,e.value)
+            checkSize()
+        }
+    }
+
+    /**
+     * Get the value associated with the [key]. It makes the [key] a MRU (last to delete)
+     */
+    override fun get(key: K): V? {
+        return cache[key]?.also {
+            cache.remove(key)
+            cache[key] = it
+        }
+    }
+
+    override fun toString(): String = cache.toString()
+}

src/commonMain/kotlin/net/sergeych/collections/SortedList.kt

@@ -0,0 +1,199 @@
+package net.sergeych.collections
+
+/**
+ * Automatically mutable sorted list based on binary search and a given comparing function.
+ * To construct list of comparable elements use [invoke]. There is a secondary constructor
+ * to use with existing [Comparator] instance.
+ *
+ * While the sorted list is mutable, it does not implement `MutableList` because indexed
+ * assignments are not possible keeping sort order; use [add] instead.
+ *
+ * It is possible to store several equal values and retrieve them all. See [add] and [addIfNotExists].
+ */
+class SortedList<T: Any>(
+    private val list: MutableList<T> = mutableListOf(),
+    private val compare: (T,T) -> Int
+)
+    : List<T> by list
+{
+    @Suppress("unused")
+    constructor(list: MutableList<T>, comparator: Comparator<T>)
+            : this(list,{ a, b -> comparator.compare(a,b) })
+
+    private fun binarySearch(element: T): Int {
+        var low = 0
+        var high = this.size - 1
+
+        while (low <= high) {
+            val mid = (low + high).ushr(1) // unsigned shift right, equivalent to integer division of sum by 2
+            val midVal = list[mid]
+            val cmp = compare(element,midVal)
+
+            when {
+                cmp < 0 -> high = mid - 1
+                cmp > 0 -> low = mid + 1
+                else -> return mid // key found
+            }
+        }
+        return -(low + 1) // key not found, insertion point is -(low + 1)
+    }
+
+    /**
+     * Find any element equals to value using fast binary search.
+     *
+     * Note that if there are many elements that are equal to [value] using the [compare],
+     * it will return index of some of it. Use [findFirst] and [findLast] if needed.
+     *
+     * @return found value or null
+     */
+    fun find(value: T): T? {
+        val i = binarySearch(value)
+        return if( i < 0 ) null else list[i]
+    }
+
+    /**
+     * Find all elements equal to the value.
+     * @return list of found elements, or an empty list.
+     */
+    fun findAll(value: T): List<T> {
+        val result = mutableListOf<T>()
+        val start = binarySearch(value)
+        if( start >= 0) {
+            for( i in start ..< size ) {
+                val element = list[i]
+                if( compare(value, element) == 0 )
+                    result += element
+                else
+                    break
+            }
+            if( start > 0) {
+                for( i in (start-1) downTo 0) {
+                    val element = list[i]
+                    if (compare(value, element) == 0)
+                        result += element
+                    else
+                        break
+                }
+            }
+        }
+        return result
+    }
+
+    /**
+     * Add all values. Duplicates will also be added.
+     */
+    fun add(vararg values: T) {
+        for( value in values ) {
+            val i = binarySearch(value)
+            if (i >= 0)
+                list.add(i + 1, value)
+            else
+                list.add(-(i + 1), value)
+        }
+    }
+
+    /**
+     * Remove one element equals to value.
+     * @return true if the element has been removed
+     */
+    fun remove(value: T): Boolean {
+        val i = binarySearch(value)
+        return if( i >= 0) {
+            list.removeAt(i)
+            true
+        }
+        else false
+    }
+
+    /**
+     * Remove element at index.
+     * @return element that has been removed
+     */
+    @Suppress("unused")
+    fun removeAt(index: Int): T = list.removeAt(index)
+
+    /**
+     * Optimized, binary search based version.
+     * @returns index of the _first_ occurrence of the element, or -1
+     */
+    override fun indexOf(element: T): Int {
+        var i = binarySearch(element)
+        if( i < 0 ) return -1
+        while( i > 0 && compare(element, list[i-1]) == 0) i--
+        return i
+    }
+
+    /**
+     * Optimized, binary search based version.
+     * @returns index of the _last_ occurrence of the element, or -1
+     */
+    override fun lastIndexOf(element: T): Int {
+        var i = binarySearch(element)
+        if( i < 0 ) return  -1
+        while( i < list.size && compare(element, list[i+1])==0) i++
+        return i
+    }
+
+    /**
+     * Optimized, binary search based, first occurrence of the element.
+     *
+     * Note that the order of 'equal' elements is unspecified, order of appearance is not kept.
+     */
+    fun findFirst(element: T): T? {
+        val i = indexOf(element)
+        return if( i < 0 ) null else list[i]
+    }
+
+    /**
+     * Optimized, binary search based search of the last occurrence of the element
+     *
+     * Note that the order of 'equal' elements is unspecified, order of appearance is not kept.
+     */
+    fun findLast(element: T): T? {
+        val i = lastIndexOf(element)
+        return if( i < 0 ) null else list[i]
+    }
+
+    /**
+     * Remove all elements equals to value.
+     * @return number of removed elements
+     */
+    fun removeAll(value: T): Int {
+        var start = binarySearch(value)
+        var count = 0
+        while( start < size && compare(value, list[start]) == 0 ) {
+            list.removeAt(start)
+            count++
+        }
+        while( start > 0 && compare(value, list[--start]) == 0) {
+            list.removeAt(start)
+            count++
+        }
+        return count
+    }
+
+    override operator fun contains(element: T): Boolean = binarySearch(element) >= 0
+
+    /**
+     * Add a value if it is not yet in the list.
+     * @return true if the value was added and false if it is already in the list, and was not added.
+     */
+    fun addIfNotExists(value: T): Boolean {
+        val i = binarySearch(value)
+        return if( i < 0) {
+            list.add(-(i + 1), value)
+            true
+        }
+        else false
+
+    }
+
+    companion object {
+        /**
+         * Construct list of elements from comparable instances.
+         */
+        operator fun <T: Comparable<T>>invoke(vararg values: T): SortedList<T> =
+            SortedList(values.toList().sorted().toMutableList()) { a, b -> a.compareTo(b) }
+    }
+
+}

src/commonMain/kotlin/net/sergeych/tools/Expiring.kt

@@ -0,0 +1,24 @@
+package net.sergecyh.diwan.tools
+
+import kotlin.time.Clock
+import kotlin.time.Duration
+import kotlin.time.Instant
+
+/**
+ * Value with expiration.
+ */
+@Suppress("unused")
+class Expiring<T>(
+    val value: T,
+    val expiresAt: Instant,
+) {
+    constructor(value: T, expiresIn: Duration) : this(value, Clock.System.now() + expiresIn)
+
+    /**
+     * @return value if not expired, null otherwise
+     */
+    fun valueOrNull(): T? = if( isExpired ) value else null
+
+    val isExpired: Boolean get() = expiresAt < Clock.System.now()
+    val isOk: Boolean get() = !isExpired
+}

src/commonMain/kotlin/net/sergeych/tools/IndividualLock.kt

@@ -0,0 +1,29 @@
+@file:Suppress("unused")
+
+package net.sergecyh.diwan.tools
+
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
+/**
+ * Experimental
+ *
+ * set of mutexes associated with keys `K`, so each key can have its own mutex
+ * used with [lock] or [withLock]
+ */
+class IndividualLock<K> {
+
+    private val access = Mutex()
+    private val locks = mutableMapOf<K, Mutex>()
+
+    suspend inline fun <T>withLock(key: K, block: ()->T): T = lock(key).use { block() }
+
+    suspend fun lock(key: K): AutoCloseable {
+        val m = access.withLock {
+            locks.getOrPut(key) { Mutex() }
+        }
+        m.lock()
+        return AutoCloseable { m.unlock() }
+    }
+
+}

src/commonMain/kotlin/net/sergeych/tools/OncePer.kt

@@ -0,0 +1,44 @@
+package net.sergecyh.diwan.tools
+
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
+
+/**
+ * Coroutine-based unique "once-per-key" executor.
+ *
+ * When [invoke] is called, it checks that there is already invocation in progress
+ * and either wait for it to complete or start a new one.
+ * @param K key value, should have valid `hashCode` and `equals`, e.g., suitable to be a map key
+ */
+@Suppress("unused")
+class OncePer<K> {
+    private val access = Mutex()
+
+    private val queue = mutableMapOf<K,CompletableDeferred<Any>>()
+
+    /**
+     * Execute [f] as unique-per-key [key]. If such invocation is in progress, it suspends than returns
+     * its result. If there is no invocation for such a key, start new invocation.
+     *
+     * __Important note__ all simultaneous invocation should have the same [R] type, or, at least, a type
+     * _castable to [R]_.
+     */
+    suspend operator fun <R: Any>invoke(key: K, f: suspend ()->R ): R {
+        var mustStart = false
+        val d = access.withLock {
+            queue.getOrPut(key) {
+                CompletableDeferred<Any>().also { mustStart = true }
+            }
+        }
+        if( mustStart ) {
+            d.complete(f())
+            access.withLock {
+                queue.remove(key)
+            }
+        }
+        @Suppress("UNCHECKED_CAST")
+        return d.await() as R
+    }
+}

src/commonMain/kotlin/net/sergeych/tools/RateLimiter.kt

@@ -0,0 +1,27 @@
+package net.sergecyh.diwan.tools
+
+import kotlin.time.Clock
+import kotlin.time.Duration
+import kotlin.time.Instant
+
+/**
+ * Experimental.
+ *
+ * limit invocations rate of [invoke] to once per [minimalInterval] or less frequent.
+ * Note that it is not a debouncing, it just ignores too frequent calls!
+ */
+@Suppress("unused")
+class RateLimiter(val minimalInterval: Duration) {
+    var lastExecutedAt = Instant.DISTANT_PAST
+        private set
+
+    /**
+     * invoke [f] if the last invocation was earlier than now minus [minimalInterval], otherwise
+     * do nothing.
+     * @return the value returned by [f] if it was actually invoked this time, null otherwise
+     */
+    suspend operator fun <T> invoke(f: suspend () -> T): T? =
+        if (Clock.System.now() - lastExecutedAt > minimalInterval) {
+            f().also { lastExecutedAt = Clock.System.now() }
+        } else null
+}

src/commonTest/kotlin/bipack/BipackEncoderTest.kt

@@ -1,7 +1,5 @@
 package bipack
 
-import kotlinx.datetime.Clock
-import kotlinx.datetime.Instant
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 import net.sergeych.bintools.encodeToHex
@@ -13,6 +11,8 @@ import kotlin.test.Test
 import kotlin.test.assertContentEquals
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
+import kotlin.time.Clock
+import kotlin.time.Instant
 
 @Serializable
 data class Foobar1N(val bar: Int, val foo: Int = 117)
@@ -30,6 +30,7 @@ data class Foobar2(val bar: Int, val foo: Int, val other: Int = -1)
 @Framed
 data class FoobarF1(val bar: Int, val foo: Int = 117)
 
+@Suppress("unused")
 @Serializable
 @Framed
 @SerialName("bipack.FoobarF1")
@@ -440,4 +441,21 @@ class BipackEncoderTest {
         println(y)
     }
 
+
+    @Serializable
+    data class T1(@Fixed val i: Byte)
+
+    @Test
+    fun testFixedByte() {
+        fun t1(i: Int) {
+            val packed = BipackEncoder.encode(T1(i.toByte()))
+            println(packed.toDump())
+            assertEquals(1, packed.size)
+            assertEquals(i, BipackDecoder.decode<T1>(packed).i.toInt())
+        }
+        t1(127)
+        t1(-127)
+        t1(1)
+        t1(-1)
+    }
 }

src/commonTest/kotlin/bipack/StorageTest.kt

@@ -0,0 +1,60 @@
+package bipack
+
+import net.sergeych.bintools.*
+import net.sergeych.collections.bitSetOf
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertNull
+
+class StorageTest {
+    @Test
+    fun storageTest3() {
+        val s1 = MemoryKVStorage()
+
+        val s2 = defaultNamedStorage("test_mp_bintools2")
+        s2.clear()
+
+        s1.write("foo", "bar")
+        s1.write("foo2", "bar2")
+
+        s2.write("foo", "foobar")
+        s2.write("bar", "buzz")
+        s2.write("reason", 42)
+
+        assertEquals("bar", s1.read("foo"))
+        assertEquals("bar2", s1.read("foo2"))
+        assertNull(s1.get("bar"))
+
+        val reason: Int? by s1.optStored()
+        assertNull(s1.get("reason"))
+        assertNull(reason)
+
+        s1.connectToStorage(s2)
+
+        // s1 overwrites s2!
+        assertEquals("bar", s1.read("foo"))
+
+        // don't change
+        assertEquals("bar2", s1.read("foo2"))
+
+        // pull from s1
+        assertEquals("buzz", s1.read("bar"))
+
+        assertEquals(42, s1.read("reason"))
+        assertEquals(42, reason)
+    }
+
+    @Test
+    fun bitSetEquityTest() {
+        val a = bitSetOf(1, 12)
+        val b = bitSetOf(12, 1)
+        assertEquals(a, b)
+        assertEquals(b, a)
+        a += 1230
+        assertFalse { a == b }
+        a -= 1230
+        assertEquals(a, b)
+        assertEquals(b, a)
+    }
+}

src/commonTest/kotlin/collections/CollectionsTest.kt

@@ -0,0 +1,166 @@
+package collections
+
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.test.advanceTimeBy
+import kotlinx.coroutines.test.resetMain
+import kotlinx.coroutines.test.runTest
+import kotlinx.coroutines.test.setMain
+import net.sergeych.bintools.toDump
+import net.sergeych.bipack.BipackEncoder
+import net.sergeych.collections.*
+import kotlin.test.*
+import kotlin.time.Duration.Companion.milliseconds
+
+class CollectionsTest {
+
+    @Test
+    fun testSortedList1() {
+        val a1 = SortedList(5, 4, 3, 9, 1)
+        assertTrue { 4 in a1 }
+        assertTrue { 14 !in a1 }
+        fun <T : Comparable<T>> test(x: SortedList<T>) {
+            var last: T? = null
+            for (i in x.toList()) {
+                if (last == null) last = i
+                else if (last > i) fail("invalid order: $last should be <= $i")
+                assertContains(x, i)
+            }
+        }
+        test(a1)
+        a1.add(11, 3, 2, 1, 0, 9, 22, -55, 0, 1, 0)
+        println(a1.toList())
+        assertEquals(listOf(-55, 0, 0, 0, 1, 1, 1, 2, 3, 3, 4, 5, 9, 9, 11, 22), a1.toList())
+        assertEquals(11, a1.find(11))
+        assertEquals(listOf(0, 0, 0), a1.findAll(0))
+        assertEquals(listOf(11), a1.findAll(11))
+        assertEquals(listOf(3, 3), a1.findAll(3))
+        assertTrue { a1.remove(3) }
+        assertEquals(listOf(3), a1.findAll(3))
+        assertTrue { a1.remove(3) }
+        assertEquals(listOf(), a1.findAll(3))
+        assertTrue { 3 !in a1 }
+        assertEquals(3, a1.findAll(1).size)
+        assertEquals(3, a1.removeAll(1))
+        assertTrue { 1 !in a1 }
+        assertEquals(listOf(-55, 0, 0, 0, 2, 4, 5, 9, 9, 11, 22), a1.toList())
+    }
+
+
+    @Test
+    fun expirableAsyncCacheTest() = runTest {
+        val removedValues = mutableSetOf<Int>()
+        val m = ExpirableAsyncCache<String, Int>(500.milliseconds) {
+            removedValues += it
+        }
+        m.put("one", 1)
+        m.put("two", 2)
+        assertTrue("one" in m)
+        assertTrue("two" in m)
+        assertEquals(1, m.get("one"))
+        assertEquals(2, m.get("two"))
+        assertTrue { removedValues.isEmpty() }
+
+        m.put("one", 11)
+        assertEquals(11, m.get("one"))
+        assertEquals(removedValues, setOf(1))
+
+        m.getOrDefault("two", 22)
+        assertEquals(2, m.get("two"))
+
+        m.getOrPut("two") { 222 }
+        assertEquals(2, m.get("two"))
+
+        m.getOrPut("three") { 3 }
+        assertEquals(3, m.get("three"))
+        // This sadly is not working
+//        delay(2000)
+//        advanceTimeBy(2000)
+//        delay(1000)
+//        assertNull(m.get("one"))
+    }
+
+    enum class Nn {
+        One, Two, Three
+    }
+
+    @Test
+    fun bitsetTest() {
+        fun checkAdd(vararg values: Int) {
+            val x = bitSetOf(*values)
+            println(":: ${values.toList()}: ${x.toHex()}")
+            assertEquals(values.toSet(), x.toIntSet())
+            for (i in values) {
+                assertTrue(i in x, "failed $i in ${values.toList()}")
+            }
+        }
+        checkAdd(0, 1, 2, 3)
+        val src = intArrayOf(31, 32, 33, 60, 61, 62, 63, 64, 65)
+        checkAdd(*src)
+
+        assertEquals(src.toSet(), src.toBitSet().toIntSet())
+        assertFalse { src.toSet() != src.toBitSet() }
+        assertFalse { src.toSet() + 17 == src.toBitSet() }
+        assertEquals(src.toBitSet() + 17, src.toSet() + 17, )
+        assertTrue { src.toSet() + 17 == src.toBitSet() + 17 }
+        assertTrue { src.toBitSet() + 17 == src.toBitSet() + 17 }
+
+        var y = src.toBitSet() + 2
+        assertTrue { y.retainAll(setOf(1, 3, 31, 32, 33)) }
+        assertEquals(setOf(31, 32, 33), y.toIntSet())
+        assertFalse { y.retainAll(setOf(1, 3, 31, 32, 33)) }
+
+        y = src.toBitSet() + 2
+        for (i in setOf(2, 31, 32, 33))
+            assertTrue(i in y, "failed $i in ${y.toList()}")
+        assertTrue { y.retainAll(bitSetOf(1, 3, 31, 32, 33)) }
+        assertEquals(setOf(31, 32, 33), y.toIntSet())
+        assertFalse { y.retainAll(setOf(1, 3, 31, 32, 33)) }
+
+        var z = src.toBitSet() + 2
+        assertTrue { z.removeAll(setOf(31, 65)) }
+        assertEquals(listOf(2, 32, 33, 60, 61, 62, 63, 64), z.toList())
+        assertFalse { z.removeAll(setOf(31, 65)) }
+
+        z = src.toBitSet() + 2
+        assertTrue { z.removeAll(bitSetOf(31, 65)) }
+        assertEquals(listOf(2, 32, 33, 60, 61, 62, 63, 64), z.toList())
+        assertFalse { z.removeAll(setOf(31, 65)) }
+
+        z = src.toBitSet() + 2
+        assertTrue { z.removeAll(bitSetOf(31, 32)) }
+        assertEquals(listOf(2, 33, 60, 61, 62, 63, 64, 65), z.toList())
+        assertFalse { z.removeAll(setOf(31, 4)) }
+
+        assertTrue {
+            BipackEncoder.encode(src.toSet()).size > BipackEncoder.encode(src.toBitSet()).size
+        }
+
+        assertFalse { z includes Nn.Two }
+        assertTrue { z includes Nn.Three }
+        assertTrue { z + 1 includesAll listOf(Nn.Three, Nn.Two) }
+
+        assertEquals(setOf(Nn.One, Nn.Three), bitSetOf(0, 2).toEnumSet())
+        assertTrue { z + 1 includesAny setOf(Nn.One, Nn.Two) }
+    }
+
+    @Test
+    fun bitsetEnumsTest() {
+        val a = bitSetOfEnum(Nn.One)
+        assertTrue { a includes Nn.One }
+        assertFalse { a includes Nn.Two }
+        assertFalse { a includes Nn.Three }
+        a.insert(Nn.Three)
+        assertEquals(setOf(Nn.One, Nn.Three), a.toEnumSet())
+        a.delete(Nn.One)
+        assertEquals(setOf(Nn.Three), a.toEnumSet())
+        a.insertAll(listOf(Nn.Two, Nn.Three))
+        assertEquals(setOf(Nn.Two, Nn.Three), a.toEnumSet())
+        assertTrue { a includesAll listOf(Nn.Two, Nn.Three) }
+        assertFalse { a includesAll listOf(Nn.One, Nn.Two) }
+        assertTrue { a includesAny listOf(Nn.One, Nn.Two) }
+        a.deleteAll(listOf(Nn.Two, Nn.Three, Nn.One))
+        assertTrue { a.isEmpty() }
+        assertTrue { a.toEnumSet<Nn>().isEmpty() }
+    }
+}

src/jvmMain/kotlin/net/sergeych/synctools/ContinuationHandler.kt

@@ -0,0 +1,34 @@
+@file:Suppress("unused")
+
+package net.sergeych.synctools
+
+import java.nio.channels.CompletionHandler
+import kotlin.coroutines.Continuation
+import kotlin.coroutines.resume
+import kotlin.coroutines.resumeWithException
+
+/**
+ * Helper class to handle Java continuation with Kotlin coroutines.
+ * Usage sample:
+ * ```kotlin
+ * val socket = withContext(Dispatchers.IO) {
+ *     AsynchronousSocketChannel.open()
+ * }
+ * suspendCoroutine { cont ->
+ *     socket.connect(address.socketAddress, cont, VoidCompletionHandler)
+ * }
+ * ```
+ */
+open class ContinuationHandler<T> : CompletionHandler<T, Continuation<T>> {
+    override fun completed(result: T, attachment: Continuation<T>) {
+        attachment.resume(result)
+    }
+
+    override fun failed(exc: Throwable, attachment: Continuation<T>) {
+        attachment.resumeWithException(exc)
+    }
+}
+
+object VoidCompletionHandler : ContinuationHandler<Void>()
+
+object IntCompletionHandler : ContinuationHandler<Int>()

src/wasmJsTest/kotlin/EmptyTest.kt

@@ -1,9 +0,0 @@
-import kotlin.test.Test
-
-class EmptyTest {
-    @Test
-    fun emptyTest() {
-        println("hello!")
-    }
-
-}

src/wasmJsTest/kotlin/StorageTest.kt

@@ -5,10 +5,6 @@ import kotlin.test.assertNull
 import kotlin.test.assertTrue
 
 class StorageTest {
-    @Test
-    fun emptyTest() {
-        println("hello")
-    }
 
     @Test
     fun storageTest() {
@@ -27,7 +23,6 @@ class StorageTest {
         assertEquals(answer, 42)
         answer = 43
 
-        println("----------------------------------------------------------------")
         val s2 = defaultNamedStorage("test_mp_bintools")
         val foo1 by s2.stored("?", "foo")
         val answer1: Int? by s2.optStored("answer")
@@ -39,5 +34,4 @@ class StorageTest {
             s2.write("test_$i", "payload_$i")
         }
     }
-
 }