Validate sqlite header

litestream.go

@@ -1,48 +1,10 @@
 package litestream
 
 import (
-	"encoding/binary"
 	"encoding/hex"
-	"io"
 	"strings"
 )
 
-// Magic number specified at the beginning of WAL files.
-const (
-	MagicLittleEndian = 0x377f0682
-	MagicBigEndian    = 0x377f0683
-)
-
-const (
-	WriteVersionOffset = 18
-	ReadVersionOffset  = 19
-)
-
-// ReadVersion returns the SQLite write & read version.
-// Returns 1 for legacy & 2 for WAL.
-func ReadVersion(b []byte) (writeVersion, readVersion uint8, err error) {
-	if len(b) < ReadVersionOffset {
-		return 0, 0, io.ErrUnexpectedEOF
-	}
-	return b[WriteVersionOffset], b[ReadVersionOffset], nil
-}
-
-// Checksum computes a running checksum over a byte slice.
-func Checksum(bo binary.ByteOrder, s uint64, b []byte) (_ uint64, err error) {
-	// Ensure byte slice length is divisible by 8.
-	if len(b)%8 != 0 {
-		return 0, ErrChecksumMisaligned
-	}
-
-	// Iterate over 8-byte units and compute checksum.
-	s0, s1 := uint32(s>>32), uint32(s&0xFFFFFFFF)
-	for i := 0; i < len(b); i += 8 {
-		s0 += bo.Uint32(b[i:]) + s1
-		s1 += bo.Uint32(b[i+4:]) + s0
-	}
-	return uint64(s0)<<32 | uint64(s1), nil
-}
-
 // HexDump returns hexdump output but with duplicate lines removed.
 func HexDump(b []byte) string {
 	const prefixN = len("00000000")