Implement streaming API

src/commonMain/kotlin/com/infendro/hash/sha2/SHA-224.kt

@@ -1,30 +1,79 @@
 package com.infendro.hash.sha2
 
+import com.infendro.bytes.bytearray.copyInto
 import com.infendro.bytes.intarray.copyInto
 import com.infendro.hash.HashFunction
+import com.infendro.hash.sha2.`SHA-256`.Companion.c
 
-object `SHA-224` : HashFunction {
-    override val bytes: Int
-        get() = 28
+class `SHA-224` : HashFunction(28, 64) {
+    private val h = initial.copyOf()
 
-    override val block: Int
-        get() = 64
+    private val w = IntArray(64)
+    private val v = IntArray(8)
 
-    private val initial = intArrayOf(
-        -0x3efa6128, +0x367cd507,
-        +0x3070dd17, -0x08f1a6c7,
-        -0x003ff4cf, +0x68581511,
-        +0x64f98fa7, -0x4105b05c,
-    )
+    override fun reset() {
+        super.reset()
+        initial.copyInto(h)
+    }
 
-    override fun hashInto(value: ByteArray, destination: ByteArray, destinationOffset: Int) {
-        val input = `SHA-256`.pad(value)
-        val h = initial.copyOf()
+    override fun process() = process(buffer.value)
 
-        for (i in input.indices step block) {
-            val block = input.sliceArray(i..<(i + block))
-            `SHA-256`.process(h, block)
+    private fun finalize() {
+        buffer.append(0x80.toByte())
+        if (buffer.free < 8) {
+            process(buffer.value)
+            buffer.reset()
         }
+        buffer.jumpTo(56)
+        buffer.append(length * 8)
+
+        process(buffer.value)
+    }
+
+    override fun digestInto(destination: ByteArray, destinationOffset: Int) {
+        finalize()
         h.copyInto(destination, destinationOffset, endIndex = 7)
+        reset()
+    }
+
+    private fun process(block: ByteArray) {
+        block.copyInto(w)
+        for (i in 16..<64) {
+            val s0 = w[i - 15].rotateRight(7) xor w[i - 15].rotateRight(18) xor (w[i - 15] ushr 3)
+            val s1 = w[i - 2].rotateRight(17) xor w[i - 2].rotateRight(19) xor (w[i - 2] ushr 10)
+            w[i] = (w[i - 16] + s0 + w[i - 7] + s1)
+        }
+        h.copyInto(v)
+
+        repeat(64) { i ->
+            val s0 = v[0].rotateRight(2) xor v[0].rotateRight(13) xor v[0].rotateRight(22)
+            val s1 = v[4].rotateRight(6) xor v[4].rotateRight(11) xor v[4].rotateRight(25)
+            val ch = (v[4] and v[5]) xor (v[4].inv() and v[6])
+            val temp1 = v[7] + s1 + ch + c[i] + w[i]
+            val maj = (v[0] and v[1]) xor (v[0] and v[2]) xor (v[1] and v[2])
+            val temp2 = s0 + maj
+
+            v[7] = v[6]
+            v[6] = v[5]
+            v[5] = v[4]
+            v[4] = v[3] + temp1
+            v[3] = v[2]
+            v[2] = v[1]
+            v[1] = v[0]
+            v[0] = temp1 + temp2
+        }
+
+        for (i in 0..<8) {
+            h[i] += v[i]
+        }
+    }
+
+    companion object {
+        private val initial = intArrayOf(
+            -0x3efa6128, +0x367cd507,
+            +0x3070dd17, -0x08f1a6c7,
+            -0x003ff4cf, +0x68581511,
+            +0x64f98fa7, -0x4105b05c,
+        )
     }
 }