public static ulong StrToU64(string input, out bool valid)
{
var chk = Pull(0, 4) >> 4; // first four chars are checksum bits
var result = Pull(4, input.Length); // next 12 chars are the 70 value bits
var actual = SaveUtil.CRC16_CCITT(BitConverter.GetBytes(result));
valid = chk == actual;
return(result);
ulong Pull(int start, int count)
{
ulong val = 0;
for (int i = start; i < count; i++)
{
var c = input[i];
if (c == '-')
{
continue;
}
val <<= 5;
val |= Get5BitFromChar(c) & 0b11111;
}
return(val);
}
}
protected override void SetChecksums()
{
int[][] c = GetChecksumOffsets(Version);
if (c == null)
{
return;
}
BitConverter.GetBytes(SaveUtil.CRC16_CCITT(Data, c[0][0] + GBO, c[0][1] - c[0][0])).CopyTo(Data, c[0][2] + GBO);
BitConverter.GetBytes(SaveUtil.CRC16_CCITT(Data, c[1][0] + SBO, c[1][1] - c[1][0])).CopyTo(Data, c[1][2] + SBO);
}
private static ulong StringToUInt64(string s)
{
// First 4 characters act as the checksum
ulong v1 = 0;
ulong v2 = 0;
for (int i = 0; i < 4; i++)
{
var c = CharToU16(s[i]);
if (c == INVALID)
{
return(INVALID);
}
v2 = (uint)(((v1 | c) >> 27) | (v2 << 5));
v1 = (uint)((v1 | c) << 5);
}
var crc = ((v1 >> 5) | (uint)(v2 << 27)) >> 4;
crc |= (v2 >> 5) << 28 | (v2 >> 9) << 32;
// Last 12 characters act as the file ID (returned value)
ulong val = 0;
for (int i = 4; i < 16; i++)
{
var c = CharToU16(s[i]);
if (c == INVALID)
{
return(INVALID);
}
var v14 = val | c;
val = (val & 0xFFFFFFFF00000000) | (uint)(val | c);
if (i == 0xF)
{
continue;
}
val = (uint)((val >> 32) << 5) << 32 | (uint)val | (v14 >> 27);
val = (val & 0xFFFFFFFF00000000) | (uint)(v14 << 5);
}
if (SaveUtil.CRC16_CCITT(BitConverter.GetBytes(val)) != crc)
{
return(uint.MaxValue);
}
return(val);
}
protected override void SetChecksums()
{
// Check for invalid block lengths
if (Blocks.Length < 3) // arbitrary...
{
Debug.WriteLine("Not enough blocks ({0}), aborting SetChecksums", Blocks.Length);
return;
}
// Apply checksums
foreach (BlockInfo b in Blocks)
{
byte[] array = Data.Skip(b.Offset).Take(b.Length).ToArray();
ushort chk = SaveUtil.CRC16_CCITT(array);
BitConverter.GetBytes(chk).CopyTo(Data, b.ChecksumOffset);
BitConverter.GetBytes(chk).CopyTo(Data, b.ChecksumMirror);
}
}
protected override void SetChecksums()
{
// Check for invalid block lengths
if (Blocks.Length < 3) // arbitrary...
{
Debug.WriteLine("Not enough blocks ({0}), aborting SetChecksums", Blocks.Length);
return;
}
// Apply checksums
for (int i = 0; i < Blocks.Length; i++)
{
if (Blocks[i].Length + Blocks[i].Offset > Data.Length)
{ Debug.WriteLine("Block {0} has invalid offset/length value.", i); return; }
byte[] array = new byte[Blocks[i].Length];
Array.Copy(Data, Blocks[i].Offset, array, 0, array.Length);
BitConverter.GetBytes(SaveUtil.CRC16_CCITT(array)).CopyTo(Data, BlockInfoOffset + 6 + i * 8);
}
}
public static string U64ToStr(ulong input, bool insertDash)
{
uint chk = SaveUtil.CRC16_CCITT(BitConverter.GetBytes(input));
var buff = new char[16];
int ctr = 15;
Push(input, 12); // store value bits
Push(chk << 4, 4); // store checksum bits
return(!insertDash?string.Concat(buff) : GetStringWithDashesEvery(buff, 4));
void Push(ulong v, int count)
{
for (int i = 0; i < count; i++)
{
buff[ctr--] = Set5BitToChar((char)(v & 0b11111));
v >>= 5;
}
}
}
private ushort GetChecksum(byte[] data) => SaveUtil.CRC16_CCITT(data, Offset, Length);
