sapi_checksum.c

Go to the documentation of this file.

 
#include <string.h>
#include "safeapi/redundancy/checksum/sapi_checksum.h"
#include "safeapi/oal/timer/sapi_timer.h"
 
/* ============================================================================
 * CRC-64 Lookup Tables (Pre-computed)
 * ========================================================================== */

static const uint64_t g_crc64_ertms_table[256] = {
    0x0000000000000000ULL, 0x0B2CAB2AF58BDC79ULL, 0x16595655EB17B8F2ULL,
    0x1D75FD7F1E9C648BULL, 0x162C6BDB0AAEBB67ULL, 0x1D00C0F1FF25671EULL,
    0x00753D8EE1B90395ULL, 0x0B5996A41432DFECULL, 0x16C610C6C9DCBC4DULL,
    0x1DEABBEC3C576034ULL, 0x009F469322CB04BFULL, 0x0BB3EDB9D740D8C6ULL,
    0x00EA7B1DC372072AULL, 0x0BC6D03736F9DB53ULL, 0x16B32D482865BFD8ULL,
    0x1D9F8662DDEE63A1ULL, 0x1712E6FD4F38B219ULL, 0x1C3E4DD7BAB36E60ULL,
    0x014BB0A8A42F0AEBULL, 0x0A671B8251A4D692ULL, 0x013E8D264596097EULL,
    0x0A12260CB01DD507ULL, 0x1767DB73AE81B18CULL, 0x1C4B70595B0A6DF5ULL,
    0x01D4F63B86E40E54ULL, 0x0AF85D11736FD22DULL, 0x178DA06E6DF3B6A6ULL,
    0x1CA10B4498786ADFULL, 0x17F89DE08C4AB533ULL, 0x1CD436CA79C1694AULL,
    0x01A1CBB5675D0DC1ULL, 0x0A8D609F92D6D1B8ULL, 0x14BB0A8A42F0AEB1ULL,
    0x1F97A1A0B77B72C8ULL, 0x02E25CDFA9E71643ULL, 0x09CEF7F55C6CCA3AULL,
    0x02976151485E15D6ULL, 0x09BBCA7BBDD5C9AFULL, 0x14CE3704A349AD24ULL,
    0x1FE29C2E56C2715DULL, 0x027D1A4C8B2C12FCULL, 0x0951B1667EA7CE85ULL,
    0x14244C19603BAA0EULL, 0x1F08E73395B07677ULL, 0x145171978182A99BULL,
    0x1F7DDABD740975E2ULL, 0x020827C26A951169ULL, 0x09248CE89F1ECD10ULL,
    0x03A9EC770DC81CA8ULL, 0x0885475DF843C0D1ULL, 0x15F0BA22E6DFA45AULL,
    0x1EDC110813547823ULL, 0x158587AC0766A7CFULL, 0x1EA92C86F2ED7BB6ULL,
    0x03DCD1F9EC711F3DULL, 0x08F07AD319FAC344ULL, 0x156FFCB1C414A0E5ULL,
    0x1E43579B319F7C9CULL, 0x0336AAE42F031817ULL, 0x081A01CEDA88C46EULL,
    0x0343976ACEBA1B82ULL, 0x086F3C403B31C7FBULL, 0x151AC13F25ADA370ULL,
    0x1E366A15D0267F09ULL, 0x13E8D264596097E1ULL, 0x18C4794EACEB4B98ULL,
    0x05B18431B2772F13ULL, 0x0E9D2F1B47FCF36AULL, 0x05C4B9BF53CE2C86ULL,
    0x0EE81295A645F0FFULL, 0x139DEFEAB8D99474ULL, 0x18B144C04D52480DULL,
    0x052EC2A290BC2BACULL, 0x0E0269886537F7D5ULL, 0x137794F77BAB935EULL,
    0x185B3FDD8E204F27ULL, 0x1302A9799A1290CBULL, 0x182E02536F994CB2ULL,
    0x055BFF2C71052839ULL, 0x0E775406848EF440ULL, 0x04FA3499165825F8ULL,
    0x0FD69FB3E3D3F981ULL, 0x12A362CCFD4F9D0AULL, 0x198FC9E608C44173ULL,
    0x12D65F421CF69E9FULL, 0x19FAF468E97D42E6ULL, 0x048F0917F7E1266DULL,
    0x0FA3A23D026AFA14ULL, 0x123C245FDF8499B5ULL, 0x19108F752A0F45CCULL,
    0x0465720A34932147ULL, 0x0F49D920C118FD3EULL, 0x04104F84D52A22D2ULL,
    0x0F3CE4AE20A1FEABULL, 0x124919D13E3D9A20ULL, 0x1965B2FBCBB64659ULL,
    0x0753D8EE1B903950ULL, 0x0C7F73C4EE1BE529ULL, 0x110A8EBBF08781A2ULL,
    0x1A262591050C5DDBULL, 0x117FB335113E8237ULL, 0x1A53181FE4B55E4EULL,
    0x0726E560FA293AC5ULL, 0x0C0A4E4A0FA2E6BCULL, 0x1195C828D24C851DULL,
    0x1AB9630227C75964ULL, 0x07CC9E7D395B3DEFULL, 0x0CE03557CCD0E196ULL,
    0x07B9A3F3D8E23E7AULL, 0x0C9508D92D69E203ULL, 0x11E0F5A633F58688ULL,
    0x1ACC5E8CC67E5AF1ULL, 0x10413E1354A88B49ULL, 0x1B6D9539A1235730ULL,
    0x06186846BFBF33BBULL, 0x0D34C36C4A34EFC2ULL, 0x066D55C85E06302EULL,
    0x0D41FEE2AB8DEC57ULL, 0x1034039DB51188DCULL, 0x1B18A8B7409A54A5ULL,
    0x06872ED59D743704ULL, 0x0DAB85FF68FFEB7DULL, 0x10DE788076638FF6ULL,
    0x1BF2D3AA83E8538FULL, 0x10AB450E97DA8C63ULL, 0x1B87EE246251501AULL,
    0x06F2135B7CCD3491ULL, 0x0DDEB8718946E8E8ULL, 0x1D4F63B86E40E541ULL,
    0x1663C8929BCB3938ULL, 0x0B1635ED85575DB3ULL, 0x003A9EC770DC81CAULL,
    0x0B63086364EE5E26ULL, 0x004FA3499165825FULL, 0x1D3A5E368FF9E6D4ULL,
    0x1616F51C7A723AADULL, 0x0B89737EA79C590CULL, 0x00A5D85452178575ULL,
    0x1DD0252B4C8BE1FEULL, 0x16FC8E01B9003D87ULL, 0x1DA518A5AD32E26BULL,
    0x1689B38F58B93E12ULL, 0x0BFC4EF046255A99ULL, 0x00D0E5DAB3AE86E0ULL,
    0x0A5D854521785758ULL, 0x01712E6FD4F38B21ULL, 0x1C04D310CA6FEFAAULL,
    0x1728783A3FE433D3ULL, 0x1C71EE9E2BD6EC3FULL, 0x175D45B4DE5D3046ULL,
    0x0A28B8CBC0C154CDULL, 0x010413E1354A88B4ULL, 0x1C9B9583E8A4EB15ULL,
    0x17B73EA91D2F376CULL, 0x0AC2C3D603B353E7ULL, 0x01EE68FCF6388F9EULL,
    0x0AB7FE58E20A5072ULL, 0x019B557217818C0BULL, 0x1CEEA80D091DE880ULL,
    0x17C20327FC9634F9ULL, 0x09F469322CB04BF0ULL, 0x02D8C218D93B9789ULL,
    0x1FAD3F67C7A7F302ULL, 0x1481944D322C2F7BULL, 0x1FD802E9261EF097ULL,
    0x14F4A9C3D3952CEEULL, 0x098154BCCD094865ULL, 0x02ADFF963882941CULL,
    0x1F3279F4E56CF7BDULL, 0x141ED2DE10E72BC4ULL, 0x096B2FA10E7B4F4FULL,
    0x0247848BFBF09336ULL, 0x091E122FEFC24CDAULL, 0x0232B9051A4990A3ULL,
    0x1F47447A04D5F428ULL, 0x146BEF50F15E2851ULL, 0x1EE68FCF6388F9E9ULL,
    0x15CA24E596032590ULL, 0x08BFD99A889F411BULL, 0x039372B07D149D62ULL,
    0x08CAE4146926428EULL, 0x03E64F3E9CAD9EF7ULL, 0x1E93B2418231FA7CULL,
    0x15BF196B77BA2605ULL, 0x08209F09AA5445A4ULL, 0x030C34235FDF99DDULL,
    0x1E79C95C4143FD56ULL, 0x15556276B4C8212FULL, 0x1E0CF4D2A0FAFEC3ULL,
    0x15205FF8557122BAULL, 0x0855A2874BED4631ULL, 0x037909ADBE669A48ULL,
    0x0EA7B1DC372072A0ULL, 0x058B1AF6C2ABAED9ULL, 0x18FEE789DC37CA52ULL,
    0x13D24CA329BC162BULL, 0x188BDA073D8EC9C7ULL, 0x13A7712DC80515BEULL,
    0x0ED28C52D6997135ULL, 0x05FE27782312AD4CULL, 0x1861A11AFEFCCEEDULL,
    0x134D0A300B771294ULL, 0x0E38F74F15EB761FULL, 0x05145C65E060AA66ULL,
    0x0E4DCAC1F452758AULL, 0x056161EB01D9A9F3ULL, 0x18149C941F45CD78ULL,
    0x133837BEEACE1101ULL, 0x19B557217818C0B9ULL, 0x1299FC0B8D931CC0ULL,
    0x0FEC0174930F784BULL, 0x04C0AA5E6684A432ULL, 0x0F993CFA72B67BDEULL,
    0x04B597D0873DA7A7ULL, 0x19C06AAF99A1C32CULL, 0x12ECC1856C2A1F55ULL,
    0x0F7347E7B1C47CF4ULL, 0x045FECCD444FA08DULL, 0x192A11B25AD3C406ULL,
    0x1206BA98AF58187FULL, 0x195F2C3CBB6AC793ULL, 0x127387164EE11BEAULL,
    0x0F067A69507D7F61ULL, 0x042AD143A5F6A318ULL, 0x1A1CBB5675D0DC11ULL,
    0x1130107C805B0068ULL, 0x0C45ED039EC764E3ULL, 0x076946296B4CB89AULL,
    0x0C30D08D7F7E6776ULL, 0x071C7BA78AF5BB0FULL, 0x1A6986D89469DF84ULL,
    0x11452DF261E203FDULL, 0x0CDAAB90BC0C605CULL, 0x07F600BA4987BC25ULL,
    0x1A83FDC5571BD8AEULL, 0x11AF56EFA29004D7ULL, 0x1AF6C04BB6A2DB3BULL,
    0x11DA6B6143290742ULL, 0x0CAF961E5DB563C9ULL, 0x07833D34A83EBFB0ULL,
    0x0D0E5DAB3AE86E08ULL, 0x0622F681CF63B271ULL, 0x1B570BFED1FFD6FAULL,
    0x107BA0D424740A83ULL, 0x1B2236703046D56FULL, 0x100E9D5AC5CD0916ULL,
    0x0D7B6025DB516D9DULL, 0x0657CB0F2EDAB1E4ULL, 0x1BC84D6DF334D245ULL,
    0x10E4E64706BF0E3CULL, 0x0D911B3818236AB7ULL, 0x06BDB012EDA8B6CEULL,
    0x0DE426B6F99A6922ULL, 0x06C88D9C0C11B55BULL, 0x1BBD70E3128DD1D0ULL,
    0x1091DBC9E7060DA9ULL
};

static const uint64_t g_crc64_iso_table[256] = {
    0x0000000000000000ULL, 0x0000000000000007ULL, 0x000000000000000EULL,
    0x0000000000000009ULL, 0x000000000000001CULL, 0x000000000000001BULL,
    0x0000000000000012ULL, 0x0000000000000015ULL, 0x000000000000000FULL,
    0x0000000000000008ULL, 0x0000000000000001ULL, 0x0000000000000006ULL,
    0x0000000000000013ULL, 0x0000000000000014ULL, 0x000000000000001DULL,
    0x000000000000001AULL, 0x000000000000001EULL, 0x0000000000000019ULL,
    0x0000000000000010ULL, 0x0000000000000017ULL, 0x0000000000000002ULL,
    0x0000000000000005ULL, 0x000000000000000CULL, 0x000000000000000BULL,
    0x0000000000000011ULL, 0x0000000000000016ULL, 0x000000000000001FULL,
    0x0000000000000018ULL, 0x000000000000000DULL, 0x000000000000000AULL,
    0x0000000000000003ULL, 0x0000000000000004ULL, 0x000000000000000BULL,
    0x000000000000000CULL, 0x0000000000000005ULL, 0x0000000000000002ULL,
    0x0000000000000017ULL, 0x0000000000000010ULL, 0x0000000000000019ULL,
    0x000000000000001EULL, 0x0000000000000004ULL, 0x0000000000000003ULL,
    0x000000000000000AULL, 0x000000000000000DULL, 0x0000000000000018ULL,
    0x000000000000001FULL, 0x0000000000000016ULL, 0x0000000000000011ULL,
    0x0000000000000015ULL, 0x0000000000000012ULL, 0x000000000000001BULL,
    0x000000000000001CULL, 0x0000000000000009ULL, 0x000000000000000EULL,
    0x0000000000000007ULL, 0x0000000000000000ULL, 0x000000000000001AULL,
    0x000000000000001DULL, 0x0000000000000014ULL, 0x0000000000000013ULL,
    0x0000000000000006ULL, 0x0000000000000001ULL, 0x0000000000000008ULL,
    0x000000000000000FULL, 0x0000000000000016ULL, 0x0000000000000011ULL,
    0x0000000000000018ULL, 0x000000000000001FULL, 0x000000000000000AULL,
    0x000000000000000DULL, 0x0000000000000004ULL, 0x0000000000000003ULL,
    0x0000000000000019ULL, 0x000000000000001EULL, 0x0000000000000017ULL,
    0x0000000000000010ULL, 0x0000000000000005ULL, 0x0000000000000002ULL,
    0x000000000000000BULL, 0x000000000000000CULL, 0x0000000000000008ULL,
    0x000000000000000FULL, 0x0000000000000006ULL, 0x0000000000000001ULL,
    0x0000000000000014ULL, 0x0000000000000013ULL, 0x000000000000001AULL,
    0x000000000000001DULL, 0x0000000000000007ULL, 0x0000000000000000ULL,
    0x0000000000000009ULL, 0x000000000000000EULL, 0x000000000000001BULL,
    0x000000000000001CULL, 0x0000000000000015ULL, 0x0000000000000012ULL,
    0x000000000000001DULL, 0x000000000000001AULL, 0x0000000000000013ULL,
    0x0000000000000014ULL, 0x0000000000000001ULL, 0x0000000000000006ULL,
    0x000000000000000FULL, 0x0000000000000008ULL, 0x0000000000000012ULL,
    0x0000000000000015ULL, 0x000000000000001CULL, 0x000000000000001BULL,
    0x000000000000000EULL, 0x0000000000000009ULL, 0x0000000000000000ULL,
    0x0000000000000007ULL, 0x0000000000000003ULL, 0x0000000000000004ULL,
    0x000000000000000DULL, 0x000000000000000AULL, 0x000000000000001FULL,
    0x0000000000000018ULL, 0x0000000000000011ULL, 0x0000000000000016ULL,
    0x000000000000000CULL, 0x000000000000000BULL, 0x0000000000000002ULL,
    0x0000000000000005ULL, 0x0000000000000010ULL, 0x0000000000000017ULL,
    0x000000000000001EULL, 0x0000000000000019ULL, 0x000000000000001BULL,
    0x000000000000001CULL, 0x0000000000000015ULL, 0x0000000000000012ULL,
    0x0000000000000007ULL, 0x0000000000000000ULL, 0x0000000000000009ULL,
    0x000000000000000EULL, 0x0000000000000014ULL, 0x0000000000000013ULL,
    0x000000000000001AULL, 0x000000000000001DULL, 0x0000000000000008ULL,
    0x000000000000000FULL, 0x0000000000000006ULL, 0x0000000000000001ULL,
    0x0000000000000005ULL, 0x0000000000000002ULL, 0x000000000000000BULL,
    0x000000000000000CULL, 0x0000000000000019ULL, 0x000000000000001EULL,
    0x0000000000000017ULL, 0x0000000000000010ULL, 0x000000000000000AULL,
    0x000000000000000DULL, 0x0000000000000004ULL, 0x0000000000000003ULL,
    0x0000000000000016ULL, 0x0000000000000011ULL, 0x0000000000000018ULL,
    0x000000000000001FULL, 0x0000000000000010ULL, 0x0000000000000017ULL,
    0x000000000000001EULL, 0x0000000000000019ULL, 0x000000000000000CULL,
    0x000000000000000BULL, 0x0000000000000002ULL, 0x0000000000000005ULL,
    0x000000000000001FULL, 0x0000000000000018ULL, 0x0000000000000011ULL,
    0x0000000000000016ULL, 0x0000000000000003ULL, 0x0000000000000004ULL,
    0x000000000000000DULL, 0x000000000000000AULL, 0x000000000000000EULL,
    0x0000000000000009ULL, 0x0000000000000000ULL, 0x0000000000000007ULL,
    0x0000000000000012ULL, 0x0000000000000015ULL, 0x000000000000001CULL,
    0x000000000000001BULL, 0x0000000000000001ULL, 0x0000000000000006ULL,
    0x000000000000000FULL, 0x0000000000000008ULL, 0x000000000000001DULL,
    0x000000000000001AULL, 0x0000000000000013ULL, 0x0000000000000014ULL,
    0x000000000000000DULL, 0x000000000000000AULL, 0x0000000000000003ULL,
    0x0000000000000004ULL, 0x0000000000000011ULL, 0x0000000000000016ULL,
    0x000000000000001FULL, 0x0000000000000018ULL, 0x0000000000000002ULL,
    0x0000000000000005ULL, 0x000000000000000CULL, 0x000000000000000BULL,
    0x000000000000001EULL, 0x0000000000000019ULL, 0x0000000000000010ULL,
    0x0000000000000017ULL, 0x0000000000000013ULL, 0x0000000000000014ULL,
    0x000000000000001DULL, 0x000000000000001AULL, 0x000000000000000FULL,
    0x0000000000000008ULL, 0x0000000000000001ULL, 0x0000000000000006ULL,
    0x000000000000001CULL, 0x000000000000001BULL, 0x0000000000000012ULL,
    0x0000000000000015ULL, 0x0000000000000000ULL, 0x0000000000000007ULL,
    0x000000000000000EULL, 0x0000000000000009ULL, 0x0000000000000006ULL,
    0x0000000000000001ULL, 0x0000000000000008ULL, 0x000000000000000FULL,
    0x000000000000001AULL, 0x000000000000001DULL, 0x0000000000000014ULL,
    0x0000000000000013ULL, 0x0000000000000009ULL, 0x000000000000000EULL,
    0x0000000000000007ULL, 0x0000000000000000ULL, 0x0000000000000015ULL,
    0x0000000000000012ULL, 0x000000000000001BULL, 0x000000000000001CULL,
    0x0000000000000018ULL, 0x000000000000001FULL, 0x0000000000000016ULL,
    0x0000000000000011ULL, 0x0000000000000004ULL, 0x0000000000000003ULL,
    0x000000000000000AULL, 0x000000000000000DULL, 0x0000000000000017ULL,
    0x0000000000000010ULL, 0x0000000000000019ULL, 0x000000000000001EULL,
    0x000000000000000BULL, 0x000000000000000CULL, 0x0000000000000005ULL,
    0x0000000000000002ULL
};

static const uint64_t g_crc64_xz_table[256] = {
    0x0000000000000000ULL, 0x09A87409262A286DULL, 0x1350E8124C5450DAULL,
    0x1AF89C1B6A7E78B7ULL, 0x0EFFCC19ED95E633ULL, 0x0757B810CBBFCE5EULL,
    0x1DAF240BA1C1B6E9ULL, 0x1407500287EB9E84ULL, 0x1DFF9833DB2BCC66ULL,
    0x1457EC3AFD01E40BULL, 0x0EAF7021977F9CBCULL, 0x07070428B155B4D1ULL,
    0x1300542A36BE2A55ULL, 0x1AA8202310940238ULL, 0x0050BC387AEA7A8FULL,
    0x09F8C8315CC052E2ULL, 0x13A12C5AC36ADF4BULL, 0x1A095853E540F726ULL,
    0x00F1C4488F3E8F91ULL, 0x0959B041A914A7FCULL, 0x1D5EE0432EFF3978ULL,
    0x14F6944A08D51115ULL, 0x0E0E085162AB69A2ULL, 0x07A67C58448141CFULL,
    0x0E5EB4691841132DULL, 0x07F6C0603E6B3B40ULL, 0x1D0E5C7B541543F7ULL,
    0x14A62872723F6B9AULL, 0x00A17870F5D4F51EULL, 0x09090C79D3FEDD73ULL,
    0x13F19062B980A5C4ULL, 0x1A59E46B9FAA8DA9ULL, 0x0F1C4488F3E8F911ULL,
    0x06B43081D5C2D17CULL, 0x1C4CAC9ABFBCA9CBULL, 0x15E4D893999681A6ULL,
    0x01E388911E7D1F22ULL, 0x084BFC983857374FULL, 0x12B3608352294FF8ULL,
    0x1B1B148A74036795ULL, 0x12E3DCBB28C33577ULL, 0x1B4BA8B20EE91D1AULL,
    0x01B334A9649765ADULL, 0x081B40A042BD4DC0ULL, 0x1C1C10A2C556D344ULL,
    0x15B464ABE37CFB29ULL, 0x0F4CF8B08902839EULL, 0x06E48CB9AF28ABF3ULL,
    0x1CBD68D23082265AULL, 0x15151CDB16A80E37ULL, 0x0FED80C07CD67680ULL,
    0x0645F4C95AFC5EEDULL, 0x1242A4CBDD17C069ULL, 0x1BEAD0C2FB3DE804ULL,
    0x01124CD9914390B3ULL, 0x08BA38D0B769B8DEULL, 0x0142F0E1EBA9EA3CULL,
    0x08EA84E8CD83C251ULL, 0x121218F3A7FDBAE6ULL, 0x1BBA6CFA81D7928BULL,
    0x0FBD3CF8063C0C0FULL, 0x061548F120162462ULL, 0x1CEDD4EA4A685CD5ULL,
    0x1545A0E36C4274B8ULL, 0x1E388911E7D1F222ULL, 0x1790FD18C1FBDA4FULL,
    0x0D686103AB85A2F8ULL, 0x04C0150A8DAF8A95ULL, 0x10C745080A441411ULL,
    0x196F31012C6E3C7CULL, 0x0397AD1A461044CBULL, 0x0A3FD913603A6CA6ULL,
    0x03C711223CFA3E44ULL, 0x0A6F652B1AD01629ULL, 0x1097F93070AE6E9EULL,
    0x193F8D39568446F3ULL, 0x0D38DD3BD16FD877ULL, 0x0490A932F745F01AULL,
    0x1E6835299D3B88ADULL, 0x17C04120BB11A0C0ULL, 0x0D99A54B24BB2D69ULL,
    0x0431D14202910504ULL, 0x1EC94D5968EF7DB3ULL, 0x176139504EC555DEULL,
    0x03666952C92ECB5AULL, 0x0ACE1D5BEF04E337ULL, 0x10368140857A9B80ULL,
    0x199EF549A350B3EDULL, 0x10663D78FF90E10FULL, 0x19CE4971D9BAC962ULL,
    0x0336D56AB3C4B1D5ULL, 0x0A9EA16395EE99B8ULL, 0x1E99F1611205073CULL,
    0x17318568342F2F51ULL, 0x0DC919735E5157E6ULL, 0x04616D7A787B7F8BULL,
    0x1124CD9914390B33ULL, 0x188CB9903213235EULL, 0x0274258B586D5BE9ULL,
    0x0BDC51827E477384ULL, 0x1FDB0180F9ACED00ULL, 0x16737589DF86C56DULL,
    0x0C8BE992B5F8BDDAULL, 0x05239D9B93D295B7ULL, 0x0CDB55AACF12C755ULL,
    0x057321A3E938EF38ULL, 0x1F8BBDB88346978FULL, 0x1623C9B1A56CBFE2ULL,
    0x022499B322872166ULL, 0x0B8CEDBA04AD090BULL, 0x117471A16ED371BCULL,
    0x18DC05A848F959D1ULL, 0x0285E1C3D753D478ULL, 0x0B2D95CAF179FC15ULL,
    0x11D509D19B0784A2ULL, 0x187D7DD8BD2DACCFULL, 0x0C7A2DDA3AC6324BULL,
    0x05D259D31CEC1A26ULL, 0x1F2AC5C876926291ULL, 0x1682B1C150B84AFCULL,
    0x1F7A79F00C78181EULL, 0x16D20DF92A523073ULL, 0x0C2A91E2402C48C4ULL,
    0x0582E5EB660660A9ULL, 0x1185B5E9E1EDFE2DULL, 0x182DC1E0C7C7D640ULL,
    0x02D55DFBADB9AEF7ULL, 0x0B7D29F28B93869AULL, 0x142F0E1EBA9EA3C3ULL,
    0x1D877A179CB48BAEULL, 0x077FE60CF6CAF319ULL, 0x0ED79205D0E0DB74ULL,
    0x1AD0C207570B45F0ULL, 0x1378B60E71216D9DULL, 0x09802A151B5F152AULL,
    0x00285E1C3D753D47ULL, 0x09D0962D61B56FA5ULL, 0x0078E224479F47C8ULL,
    0x1A807E3F2DE13F7FULL, 0x13280A360BCB1712ULL, 0x072F5A348C208996ULL,
    0x0E872E3DAA0AA1FBULL, 0x147FB226C074D94CULL, 0x1DD7C62FE65EF121ULL,
    0x078E224479F47C88ULL, 0x0E26564D5FDE54E5ULL, 0x14DECA5635A02C52ULL,
    0x1D76BE5F138A043FULL, 0x0971EE5D94619ABBULL, 0x00D99A54B24BB2D6ULL,
    0x1A21064FD835CA61ULL, 0x13897246FE1FE20CULL, 0x1A71BA77A2DFB0EEULL,
    0x13D9CE7E84F59883ULL, 0x09215265EE8BE034ULL, 0x0089266CC8A1C859ULL,
    0x148E766E4F4A56DDULL, 0x1D26026769607EB0ULL, 0x07DE9E7C031E0607ULL,
    0x0E76EA7525342E6AULL, 0x1B334A9649765AD2ULL, 0x129B3E9F6F5C72BFULL,
    0x0863A28405220A08ULL, 0x01CBD68D23082265ULL, 0x15CC868FA4E3BCE1ULL,
    0x1C64F28682C9948CULL, 0x069C6E9DE8B7EC3BULL, 0x0F341A94CE9DC456ULL,
    0x06CCD2A5925D96B4ULL, 0x0F64A6ACB477BED9ULL, 0x159C3AB7DE09C66EULL,
    0x1C344EBEF823EE03ULL, 0x08331EBC7FC87087ULL, 0x019B6AB559E258EAULL,
    0x1B63F6AE339C205DULL, 0x12CB82A715B60830ULL, 0x089266CC8A1C8599ULL,
    0x013A12C5AC36ADF4ULL, 0x1BC28EDEC648D543ULL, 0x126AFAD7E062FD2EULL,
    0x066DAAD5678963AAULL, 0x0FC5DEDC41A34BC7ULL, 0x153D42C72BDD3370ULL,
    0x1C9536CE0DF71B1DULL, 0x156DFEFF513749FFULL, 0x1CC58AF6771D6192ULL,
    0x063D16ED1D631925ULL, 0x0F9562E43B493148ULL, 0x1B9232E6BCA2AFCCULL,
    0x123A46EF9A8887A1ULL, 0x08C2DAF4F0F6FF16ULL, 0x016AAEFDD6DCD77BULL,
    0x0A17870F5D4F51E1ULL, 0x03BFF3067B65798CULL, 0x19476F1D111B013BULL,
    0x10EF1B1437312956ULL, 0x04E84B16B0DAB7D2ULL, 0x0D403F1F96F09FBFULL,
    0x17B8A304FC8EE708ULL, 0x1E10D70DDAA4CF65ULL, 0x17E81F3C86649D87ULL,
    0x1E406B35A04EB5EAULL, 0x04B8F72ECA30CD5DULL, 0x0D108327EC1AE530ULL,
    0x1917D3256BF17BB4ULL, 0x10BFA72C4DDB53D9ULL, 0x0A473B3727A52B6EULL,
    0x03EF4F3E018F0303ULL, 0x19B6AB559E258EAAULL, 0x101EDF5CB80FA6C7ULL,
    0x0AE64347D271DE70ULL, 0x034E374EF45BF61DULL, 0x1749674C73B06899ULL,
    0x1EE11345559A40F4ULL, 0x04198F5E3FE43843ULL, 0x0DB1FB5719CE102EULL,
    0x04493366450E42CCULL, 0x0DE1476F63246AA1ULL, 0x1719DB74095A1216ULL,
    0x1EB1AF7D2F703A7BULL, 0x0AB6FF7FA89BA4FFULL, 0x031E8B768EB18C92ULL,
    0x19E6176DE4CFF425ULL, 0x104E6364C2E5DC48ULL, 0x050BC387AEA7A8F0ULL,
    0x0CA3B78E888D809DULL, 0x165B2B95E2F3F82AULL, 0x1FF35F9CC4D9D047ULL,
    0x0BF40F9E43324EC3ULL, 0x025C7B97651866AEULL, 0x18A4E78C0F661E19ULL,
    0x110C9385294C3674ULL, 0x18F45BB4758C6496ULL, 0x115C2FBD53A64CFBULL,
    0x0BA4B3A639D8344CULL, 0x020CC7AF1FF21C21ULL, 0x160B97AD981982A5ULL,
    0x1FA3E3A4BE33AAC8ULL, 0x055B7FBFD44DD27FULL, 0x0CF30BB6F267FA12ULL,
    0x16AAEFDD6DCD77BBULL, 0x1F029BD44BE75FD6ULL, 0x05FA07CF21992761ULL,
    0x0C5273C607B30F0CULL, 0x185523C480589188ULL, 0x11FD57CDA672B9E5ULL,
    0x0B05CBD6CC0CC152ULL, 0x02ADBFDFEA26E93FULL, 0x0B5577EEB6E6BBDDULL,
    0x02FD03E790CC93B0ULL, 0x18059FFCFAB2EB07ULL, 0x11ADEBF5DC98C36AULL,
    0x05AABBF75B735DEEULL, 0x0C02CFFE7D597583ULL, 0x16FA53E517270D34ULL,
    0x1F5227EC310D2559ULL
};
 
/* ============================================================================
 * Module State
 * ========================================================================== */

typedef struct {
    uint8_t initialized;                    
    sapi_crc64_polynomial_t polynomial;     
    const uint64_t *table;                  
    sapi_checksum_stats_t stats;            
} sapi_checksum_manager_t;

static sapi_checksum_manager_t g_checksum_manager = {0};
 
/* ============================================================================
 * API: CRC-64 Computation
 * ========================================================================== */
 
sapi_status_t sapi_checksum_crc64_init(sapi_crc64_polynomial_t polynomial)
{
    /* Verify not already initialized */
    if (g_checksum_manager.initialized != 0U) {
        return SAPI_STATUS_ALREADY_INITIALIZED;
    }
 
    /* Select appropriate lookup table */
    switch (polynomial) {
    case SAPI_CRC64_ERTMS:
        g_checksum_manager.table = g_crc64_ertms_table;
        g_checksum_manager.polynomial = SAPI_CRC64_ERTMS;
        break;
    case SAPI_CRC64_ISO:
        g_checksum_manager.table = g_crc64_iso_table;
        g_checksum_manager.polynomial = SAPI_CRC64_ISO;
        break;
    case SAPI_CRC64_XZ:
        g_checksum_manager.table = g_crc64_xz_table;
        g_checksum_manager.polynomial = SAPI_CRC64_XZ;
        break;
    default:
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    /* Initialize statistics */
    memset(&g_checksum_manager.stats, 0, sizeof(g_checksum_manager.stats));
    g_checksum_manager.initialized = 1U;
 
    return SAPI_STATUS_OK;
}
 
sapi_crc64_t sapi_checksum_crc64(const uint8_t *data, size_t size)
{
    uint64_t crc = 0xFFFFFFFFFFFFFFFFULL;  /* Initial value (all ones) */
    size_t i;
    uint8_t index;
 
    /* Verify initialization */
    if (g_checksum_manager.initialized == 0U) {
        return 0ULL;
    }
 
    /* Handle NULL data pointer */
    if (data == NULL) {
        if (size != 0U) {
            return 0ULL;
        }
        return crc;
    }
 
    /* Defense-in-depth against corrupted static state (e.g. a single-event
     * upset flipping g_checksum_manager.table without also flipping
     * .initialized) rather than a reachable API path: every branch in
     * sapi_checksum_crc64_init() above sets .table and .initialized
     * together, so .initialized == 1U already implies .table != NULL for
     * any state this module's own code can produce - not coverable by a
     * legitimate caller, and there is no public way to corrupt
     * module-static state to hit it either. Kept rather than deleted:
     * this guards a genuine hardware fault class relevant to SIL
     * contexts, not merely a defensive habit. See docs/COVERAGE_REPORT.md
     * for the accepted-exception rationale (this is the project's one
     * documented gap against the 100% branch coverage target). */
    if (g_checksum_manager.table == NULL) { /* GCOVR_EXCL_BR_LINE */
        return 0ULL; /* GCOVR_EXCL_LINE - see rationale above */
    }
 
    /* Compute CRC using lookup table (O(1) per byte) */
    for (i = 0U; i < size; i++) {
        /* Extract lower 8 bits of CRC, XOR with next data byte */
        index = (uint8_t)((crc ^ data[i]) & 0xFFU);
 
        /* Right-shift CRC by 8 bits, XOR with table entry */
        crc = (crc >> 8U) ^ g_checksum_manager.table[index];
    }
 
    /* Final XOR with all-ones */
    crc ^= 0xFFFFFFFFFFFFFFFFULL;
 
    /* Update statistics */
    g_checksum_manager.stats.total_checksums++;
 
    return crc;
}
 
sapi_status_t sapi_checksum_crc64_verify(const uint8_t *data,
                                         size_t size,
                                         sapi_crc64_t expected_crc,
                                         sapi_checksum_result_t *result_out)
{
    sapi_crc64_t computed_crc;
    sapi_status_t status;
 
    /* Verify output buffer */
    if (result_out == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    /* Compute CRC */
    computed_crc = sapi_checksum_crc64(data, size);
 
    /* Fill result structure */
    result_out->computed = computed_crc;
    result_out->expected = expected_crc;
    result_out->match = (computed_crc == expected_crc) ? 1U : 0U;
 
    /* Update statistics */
    if (result_out->match != 0U) {
        g_checksum_manager.stats.verification_passes++;
        status = SAPI_STATUS_OK;
    } else {
        g_checksum_manager.stats.verification_failures++;
        status = SAPI_STATUS_DATA_CORRUPTION;
    }
 
    return status;
}
 
sapi_crc64_polynomial_t sapi_checksum_crc64_get_polynomial(void)
{
    return g_checksum_manager.polynomial;
}
 
/* ============================================================================
 * API: Vital Channel Message Wrapper
 * ========================================================================== */
 
sapi_status_t sapi_checksum_vital_message_create(
    sapi_vital_message_t *msg_out,
    uint32_t sender_id,
    uint32_t sequence,
    const uint8_t *payload,
    size_t payload_size)
{
    sapi_timestamp_ms_t now_ms = 0U;
 
    /* Validate inputs */
    if (msg_out == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    if (payload_size > 248U) {
        g_checksum_manager.stats.payload_oversize++;
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    if ((payload == NULL) && (payload_size != 0U)) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    /* Fill message header */
    msg_out->sequence_number = sequence;
    msg_out->sender_id = sender_id;
    /* Best-effort: if no timer backend is registered, sapi_timer_now()
     * returns SAPI_STATUS_NOT_INITIALIZED and leaves now_ms at 0 -
     * timestamp_ms is diagnostic only (see sapi_clocksync.h's file-level
     * note: never the basis of comparison correctness), so this is not
     * treated as a hard failure of message creation. */
    (void)sapi_timer_now(&now_ms);
    msg_out->timestamp_ms = (uint32_t)(now_ms & 0xFFFFFFFFULL);
    msg_out->payload_size = (uint8_t)payload_size;
    msg_out->padding = 0U;
    msg_out->reserved = 0U;
 
    /* Clear payload area */
    memset(msg_out->payload, 0, sizeof(msg_out->payload));
 
    /* Copy payload */
    if ((payload != NULL) && (payload_size > 0U)) {
        memcpy(msg_out->payload, payload, payload_size);
    }
 
    /* Compute CRC-64 over entire message (including payload, excluding CRC field) */
    msg_out->crc64 = sapi_checksum_crc64(
        (const uint8_t *)msg_out,
        sizeof(*msg_out) - sizeof(msg_out->crc64)
    );
 
    return SAPI_STATUS_OK;
}
 
sapi_status_t sapi_checksum_vital_message_verify(
    const sapi_vital_message_t *msg,
    uint32_t expected_sequence,
    uint8_t *payload_out,
    size_t payload_max_size,
    uint8_t *payload_size_out)
{
    sapi_checksum_result_t check_result;
    sapi_status_t status;
 
    /* Validate inputs */
    if (msg == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    if (payload_out == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    if (payload_size_out == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    /* Check CRC-64 */
    status = sapi_checksum_crc64_verify(
        (const uint8_t *)msg,
        sizeof(*msg) - sizeof(msg->crc64),
        msg->crc64,
        &check_result
    );
 
    if (status != SAPI_STATUS_OK) {
        return SAPI_STATUS_DATA_CORRUPTION;
    }
 
    /* Check sequence number continuity */
    if (msg->sequence_number != expected_sequence) {
        g_checksum_manager.stats.sequence_errors++;
        return SAPI_STATUS_DATA_CORRUPTION;
    }
 
    /* Validate payload size */
    if (msg->payload_size > payload_max_size) {
        g_checksum_manager.stats.payload_oversize++;
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    /* Extract payload */
    if (msg->payload_size > 0U) {
        memcpy(payload_out, msg->payload, msg->payload_size);
    }
    *payload_size_out = msg->payload_size;
 
    return SAPI_STATUS_OK;
}
 
/* ============================================================================
 * API: Statistics
 * ========================================================================== */
 
sapi_status_t sapi_checksum_get_stats(sapi_checksum_stats_t *stats_out)
{
    if (stats_out == NULL) {
        return SAPI_STATUS_INVALID_PARAM;
    }
 
    *stats_out = g_checksum_manager.stats;
    return SAPI_STATUS_OK;
}
 
sapi_status_t sapi_checksum_reset_stats(void)
{
    memset(&g_checksum_manager.stats, 0, sizeof(g_checksum_manager.stats));
    return SAPI_STATUS_OK;
}