Coverage Summary for Class: Crc32 (com.georgeci.moneysurfer.data.backup.zip)

 package com.georgeci.moneysurfer.data.backup.zip
 
 /**
  * IEEE 802.3 CRC-32 — same polynomial as ZIP / PNG / `java.util.zip.CRC32`.
  *
  * Table-based, KMP-native (no `java.util.zip` on iOS).
  */
 internal class Crc32 {
     private var value: Int = 0.inv()
 
     fun update(buffer: ByteArray, offset: Int = 0, length: Int = buffer.size - offset) {
         var crc = value
         val end = offset + length
         var i = offset
         while (i < end) {
             crc = (crc ushr BITS_PER_BYTE) xor TABLE[(crc xor buffer[i].toInt()) and BYTE_MASK]
             i++
         }
         value = crc
     }
 
     fun getValue(): Long = (value.inv().toLong() and MASK_U32)
 
     companion object {
         private val TABLE: IntArray = IntArray(TABLE_SIZE).also { table ->
             for (n in 0 until TABLE_SIZE) {
                 var c = n
                 repeat(BITS_PER_BYTE) {
                     c = if (c and 1 != 0) (c ushr 1) xor POLY else c ushr 1
                 }
                 table[n] = c
             }
         }
     }
 }
 
 private const val TABLE_SIZE = 256
 private const val BITS_PER_BYTE = 8
 private const val BYTE_MASK = 0xFF
 private const val MASK_U32 = 0xFFFFFFFFL
 
 @Suppress("MagicNumber")
 private const val POLY: Int = 0xEDB88320.toInt()