public static bool Decode(StringPiece slice, out KeyPrefix prefix)
{
if (slice.Empty)
{
prefix = default(KeyPrefix);
return(false);
}
var firstByte = slice.Next();
var databaseIdBytes = ((firstByte >> 5) & 0x7) + 1;
var objectStoreIdBytes = ((firstByte >> 2) & 0x7) + 1;
var indexIdBytes = (firstByte & 0x3) + 1;
if (databaseIdBytes + objectStoreIdBytes + indexIdBytes > slice.Left)
{
prefix = default(KeyPrefix);
return(false);
}
prefix = new KeyPrefix();
return(slice.Slice(databaseIdBytes).DecodeInt(out prefix.DatabaseId) &&
slice.Slice(objectStoreIdBytes).DecodeInt(out prefix.ObjectStoreId) &&
slice.Slice(indexIdBytes).DecodeInt(out prefix.IndexId));
}
private static int CompareEncodedStringsWithLength(StringPiece slice1, StringPiece slice2, out bool ok)
{
long len1, len2;
if (!slice1.DecodeVarInt(out len1) || !slice2.DecodeVarInt(out len2) || len1 < 0 || len2 < 0)
{
ok = false;
return(0);
}
var size1 = (int)len1 * 2;
var size2 = (int)len2 * 2;
if (slice1.Left < size1 || slice2.Left < size2)
{
ok = false;
return(0);
}
// Extract the binary data, and advance the passed slices.
ok = true;
return(slice1.Slice(size1).CompareTo(slice2.Slice(size2)));
}