Introduce basic, url-safe and mime Base64 variants #KT-9823

libraries/stdlib/js/src/kotlin/io/encoding/Base64Js.kt

@@ -0,0 +1,46 @@
+/*
+ * 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/LICENSE.txt file.
+ */
+
+package kotlin.io.encoding
+
+@SinceKotlin("1.8")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+internal actual inline fun Base64.platformCharsToBytes(source: CharSequence, startIndex: Int, endIndex: Int): ByteArray {
+    return charsToBytesImpl(source, startIndex, endIndex)
+}
+
+
+@SinceKotlin("1.8")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+internal actual inline fun Base64.platformEncodeToString(source: ByteArray, startIndex: Int, endIndex: Int): String {
+    val byteResult = encodeToByteArrayImpl(source, startIndex, endIndex)
+    return bytesToStringImpl(byteResult)
+}
+
+@SinceKotlin("1.8")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+internal actual inline fun Base64.platformEncodeIntoByteArray(
+    source: ByteArray,
+    destination: ByteArray,
+    destinationOffset: Int,
+    startIndex: Int,
+    endIndex: Int
+): Int {
+    return encodeIntoByteArrayImpl(source, destination, destinationOffset, startIndex, endIndex)
+}
+
+@SinceKotlin("1.8")
+@ExperimentalStdlibApi
+@kotlin.internal.InlineOnly
+internal actual inline fun Base64.platformEncodeToByteArray(
+    source: ByteArray,
+    startIndex: Int,
+    endIndex: Int
+): ByteArray {
+    return encodeToByteArrayImpl(source, startIndex, endIndex)
+}