From 5126c603b0534cf2228b657a107a50a51fa102c7 Mon Sep 17 00:00:00 2001
From: Phillip Stephens <antidote.crk@gmail.com>
Date: Thu, 15 Feb 2018 09:20:13 -0800
Subject: [PATCH] Add CRC-64-ECMA implementation

---
 include/athena/Checksums.hpp |  1 +
 src/athena/Checksums.cpp     | 81 ++++++++++++++++++++++++++++++++++++
 2 files changed, 82 insertions(+)

diff --git a/include/athena/Checksums.hpp b/include/athena/Checksums.hpp
index bd7f7c9..67c55fb 100644
--- a/include/athena/Checksums.hpp
+++ b/include/athena/Checksums.hpp
@@ -5,6 +5,7 @@
 
 namespace athena::Checksums
 {
+atUint64 crc64(const atUint8* data, atUint64 length, atUint64 mask = 0xFFFFFFFFFFFFFFFF, atUint64 seed = 0xFFFFFFFFFFFFFFFF);
 atUint32 crc32(const atUint8* data, atUint64 length, atUint32 mask = 0xFFFFFFFF, atUint32 seed = 0xFFFFFFFF);
 atUint16 crc16CCITT(const atUint8* data, atUint64 length, atUint16 seed = 0xFFFF, atUint16 final = 0);
 atUint16 crc16(const atUint8* data, atUint64 length);
diff --git a/src/athena/Checksums.cpp b/src/athena/Checksums.cpp
index 2fc1c9c..8e55727 100644
--- a/src/athena/Checksums.cpp
+++ b/src/athena/Checksums.cpp
@@ -5,6 +5,87 @@
 
 namespace athena::Checksums
 {
+atUint64 crc64(const atUint8* data, atUint64 length, atUint64 mask, atUint64 seed)
+{
+    if (!data)
+        return 0;
+
+    atUint64 checksum = seed;
+    int pos = 0;
+
+    static const atUint64 crc64Table[256] =
+    {
+        0x0000000000000000, 0x42F0E1EBA9EA3693, 0x85E1C3D753D46D26, 0xC711223CFA3E5BB5,
+        0x493366450E42ECDF, 0x0BC387AEA7A8DA4C, 0xCCD2A5925D9681F9, 0x8E224479F47CB76A,
+        0x9266CC8A1C85D9BE, 0xD0962D61B56FEF2D, 0x17870F5D4F51B498, 0x5577EEB6E6BB820B,
+        0xDB55AACF12C73561, 0x99A54B24BB2D03F2, 0x5EB4691841135847, 0x1C4488F3E8F96ED4,
+        0x663D78FF90E185EF, 0x24CD9914390BB37C, 0xE3DCBB28C335E8C9, 0xA12C5AC36ADFDE5A,
+        0x2F0E1EBA9EA36930, 0x6DFEFF5137495FA3, 0xAAEFDD6DCD770416, 0xE81F3C86649D3285,
+        0xF45BB4758C645C51, 0xB6AB559E258E6AC2, 0x71BA77A2DFB03177, 0x334A9649765A07E4,
+        0xBD68D2308226B08E, 0xFF9833DB2BCC861D, 0x388911E7D1F2DDA8, 0x7A79F00C7818EB3B,
+        0xCC7AF1FF21C30BDE, 0x8E8A101488293D4D, 0x499B3228721766F8, 0x0B6BD3C3DBFD506B,
+        0x854997BA2F81E701, 0xC7B97651866BD192, 0x00A8546D7C558A27, 0x4258B586D5BFBCB4,
+        0x5E1C3D753D46D260, 0x1CECDC9E94ACE4F3, 0xDBFDFEA26E92BF46, 0x990D1F49C77889D5,
+        0x172F5B3033043EBF, 0x55DFBADB9AEE082C, 0x92CE98E760D05399, 0xD03E790CC93A650A,
+        0xAA478900B1228E31, 0xE8B768EB18C8B8A2, 0x2FA64AD7E2F6E317, 0x6D56AB3C4B1CD584,
+        0xE374EF45BF6062EE, 0xA1840EAE168A547D, 0x66952C92ECB40FC8, 0x2465CD79455E395B,
+        0x3821458AADA7578F, 0x7AD1A461044D611C, 0xBDC0865DFE733AA9, 0xFF3067B657990C3A,
+        0x711223CFA3E5BB50, 0x33E2C2240A0F8DC3, 0xF4F3E018F031D676, 0xB60301F359DBE0E5,
+        0xDA050215EA6C212F, 0x98F5E3FE438617BC, 0x5FE4C1C2B9B84C09, 0x1D14202910527A9A,
+        0x93366450E42ECDF0, 0xD1C685BB4DC4FB63, 0x16D7A787B7FAA0D6, 0x5427466C1E109645,
+        0x4863CE9FF6E9F891, 0x0A932F745F03CE02, 0xCD820D48A53D95B7, 0x8F72ECA30CD7A324,
+        0x0150A8DAF8AB144E, 0x43A04931514122DD, 0x84B16B0DAB7F7968, 0xC6418AE602954FFB,
+        0xBC387AEA7A8DA4C0, 0xFEC89B01D3679253, 0x39D9B93D2959C9E6, 0x7B2958D680B3FF75,
+        0xF50B1CAF74CF481F, 0xB7FBFD44DD257E8C, 0x70EADF78271B2539, 0x321A3E938EF113AA,
+        0x2E5EB66066087D7E, 0x6CAE578BCFE24BED, 0xABBF75B735DC1058, 0xE94F945C9C3626CB,
+        0x676DD025684A91A1, 0x259D31CEC1A0A732, 0xE28C13F23B9EFC87, 0xA07CF2199274CA14,
+        0x167FF3EACBAF2AF1, 0x548F120162451C62, 0x939E303D987B47D7, 0xD16ED1D631917144,
+        0x5F4C95AFC5EDC62E, 0x1DBC74446C07F0BD, 0xDAAD56789639AB08, 0x985DB7933FD39D9B,
+        0x84193F60D72AF34F, 0xC6E9DE8B7EC0C5DC, 0x01F8FCB784FE9E69, 0x43081D5C2D14A8FA,
+        0xCD2A5925D9681F90, 0x8FDAB8CE70822903, 0x48CB9AF28ABC72B6, 0x0A3B7B1923564425,
+        0x70428B155B4EAF1E, 0x32B26AFEF2A4998D, 0xF5A348C2089AC238, 0xB753A929A170F4AB,
+        0x3971ED50550C43C1, 0x7B810CBBFCE67552, 0xBC902E8706D82EE7, 0xFE60CF6CAF321874,
+        0xE224479F47CB76A0, 0xA0D4A674EE214033, 0x67C58448141F1B86, 0x253565A3BDF52D15,
+        0xAB1721DA49899A7F, 0xE9E7C031E063ACEC, 0x2EF6E20D1A5DF759, 0x6C0603E6B3B7C1CA,
+        0xF6FAE5C07D3274CD, 0xB40A042BD4D8425E, 0x731B26172EE619EB, 0x31EBC7FC870C2F78,
+        0xBFC9838573709812, 0xFD39626EDA9AAE81, 0x3A28405220A4F534, 0x78D8A1B9894EC3A7,
+        0x649C294A61B7AD73, 0x266CC8A1C85D9BE0, 0xE17DEA9D3263C055, 0xA38D0B769B89F6C6,
+        0x2DAF4F0F6FF541AC, 0x6F5FAEE4C61F773F, 0xA84E8CD83C212C8A, 0xEABE6D3395CB1A19,
+        0x90C79D3FEDD3F122, 0xD2377CD44439C7B1, 0x15265EE8BE079C04, 0x57D6BF0317EDAA97,
+        0xD9F4FB7AE3911DFD, 0x9B041A914A7B2B6E, 0x5C1538ADB04570DB, 0x1EE5D94619AF4648,
+        0x02A151B5F156289C, 0x4051B05E58BC1E0F, 0x87409262A28245BA, 0xC5B073890B687329,
+        0x4B9237F0FF14C443, 0x0962D61B56FEF2D0, 0xCE73F427ACC0A965, 0x8C8315CC052A9FF6,
+        0x3A80143F5CF17F13, 0x7870F5D4F51B4980, 0xBF61D7E80F251235, 0xFD913603A6CF24A6,
+        0x73B3727A52B393CC, 0x31439391FB59A55F, 0xF652B1AD0167FEEA, 0xB4A25046A88DC879,
+        0xA8E6D8B54074A6AD, 0xEA16395EE99E903E, 0x2D071B6213A0CB8B, 0x6FF7FA89BA4AFD18,
+        0xE1D5BEF04E364A72, 0xA3255F1BE7DC7CE1, 0x64347D271DE22754, 0x26C49CCCB40811C7,
+        0x5CBD6CC0CC10FAFC, 0x1E4D8D2B65FACC6F, 0xD95CAF179FC497DA, 0x9BAC4EFC362EA149,
+        0x158E0A85C2521623, 0x577EEB6E6BB820B0, 0x906FC95291867B05, 0xD29F28B9386C4D96,
+        0xCEDBA04AD0952342, 0x8C2B41A1797F15D1, 0x4B3A639D83414E64, 0x09CA82762AAB78F7,
+        0x87E8C60FDED7CF9D, 0xC51827E4773DF90E, 0x020905D88D03A2BB, 0x40F9E43324E99428,
+        0x2CFFE7D5975E55E2, 0x6E0F063E3EB46371, 0xA91E2402C48A38C4, 0xEBEEC5E96D600E57,
+        0x65CC8190991CB93D, 0x273C607B30F68FAE, 0xE02D4247CAC8D41B, 0xA2DDA3AC6322E288,
+        0xBE992B5F8BDB8C5C, 0xFC69CAB42231BACF, 0x3B78E888D80FE17A, 0x7988096371E5D7E9,
+        0xF7AA4D1A85996083, 0xB55AACF12C735610, 0x724B8ECDD64D0DA5, 0x30BB6F267FA73B36,
+        0x4AC29F2A07BFD00D, 0x08327EC1AE55E69E, 0xCF235CFD546BBD2B, 0x8DD3BD16FD818BB8,
+        0x03F1F96F09FD3CD2, 0x41011884A0170A41, 0x86103AB85A2951F4, 0xC4E0DB53F3C36767,
+        0xD8A453A01B3A09B3, 0x9A54B24BB2D03F20, 0x5D45907748EE6495, 0x1FB5719CE1045206,
+        0x919735E51578E56C, 0xD367D40EBC92D3FF, 0x1476F63246AC884A, 0x568617D9EF46BED9,
+        0xE085162AB69D5E3C, 0xA275F7C11F7768AF, 0x6564D5FDE549331A, 0x279434164CA30589,
+        0xA9B6706FB8DFB2E3, 0xEB46918411358470, 0x2C57B3B8EB0BDFC5, 0x6EA7525342E1E956,
+        0x72E3DAA0AA188782, 0x30133B4B03F2B111, 0xF7021977F9CCEAA4, 0xB5F2F89C5026DC37,
+        0x3BD0BCE5A45A6B5D, 0x79205D0E0DB05DCE, 0xBE317F32F78E067B, 0xFCC19ED95E6430E8,
+        0x86B86ED5267CDBD3, 0xC4488F3E8F96ED40, 0x0359AD0275A8B6F5, 0x41A94CE9DC428066,
+        0xCF8B0890283E370C, 0x8D7BE97B81D4019F, 0x4A6ACB477BEA5A2A, 0x089A2AACD2006CB9,
+        0x14DEA25F3AF9026D, 0x562E43B4931334FE, 0x913F6188692D6F4B, 0xD3CF8063C0C759D8,
+        0x5DEDC41A34BBEEB2, 0x1F1D25F19D51D821, 0xD80C07CD676F8394, 0x9AFCE626CE85B507,
+    };
+
+    while (length--)
+        checksum = crc64Table[((checksum >> 56) ^ data[pos++]) & 0xff] ^ (checksum << 8);
+
+    return checksum ^ mask;
+}
 
 atUint32 crc32(const atUint8* data, atUint64 length, atUint32 mask, atUint32 seed)
 {