Exemplo n.º 1
0
        private unsafe static bool VerifyBlockChecksum(byte *ptr, int length)
        {
            var cs = Utility.XorBytes(ptr + 8, length + HeaderSize - 8);

            if (cs != GetHeader((long)ptr).Checksum)
            {
                return(false);
            }
            return(true);
        }
Exemplo n.º 2
0
        /// <summary>
        /// Write info to byte array
        /// </summary>
        public readonly byte[] ToByteArray()
        {
            using MemoryStream ms = new();
            using (BinaryWriter writer = new(ms))
            {
                writer.Write(FasterLogRecoveryVersion); // version

                int iteratorCount = 0;
                if (Iterators != null)
                {
                    iteratorCount = Iterators.Count;
                }

                int  cookieLength   = -1;
                long cookieChecksum = 0;
                if (Cookie != null)
                {
                    cookieLength = Cookie.Length;
                    if (cookieLength > 0)
                    {
                        unsafe
                        {
                            fixed(byte *ptr = Cookie)
                            cookieChecksum = (long)Utility.XorBytes(ptr, cookieLength);
                        }
                    }
                }

                writer.Write(BeginAddress ^ UntilAddress ^ CommitNum ^ iteratorCount ^ cookieLength ^ cookieChecksum); // checksum
                writer.Write(BeginAddress);
                writer.Write(UntilAddress);
                writer.Write(CommitNum);

                writer.Write(iteratorCount);
                if (iteratorCount > 0)
                {
                    foreach (var kvp in Iterators)
                    {
                        writer.Write(kvp.Key);
                        writer.Write(kvp.Value);
                    }
                }

                writer.Write(cookieLength);
                if (cookieLength > 0)
                {
                    writer.Write(Cookie);
                }
            }
            return(ms.ToArray());
        }
Exemplo n.º 3
0
        /// <summary>
        /// Initialize from stream
        /// </summary>
        /// <param name="reader"></param>
        public void Initialize(BinaryReader reader)
        {
            int  version;
            long checkSum;

            try
            {
                version      = reader.ReadInt32();
                checkSum     = reader.ReadInt64();
                BeginAddress = reader.ReadInt64();
                UntilAddress = reader.ReadInt64();
                if (version > 0)
                {
                    CommitNum = reader.ReadInt64();
                }
                else
                {
                    CommitNum = -1;
                }
            }
            catch (Exception e)
            {
                throw new FasterException("Unable to recover from previous commit. Inner exception: " + e.ToString());
            }
            if (version < 0 || version > FasterLogRecoveryVersion)
            {
                throw new FasterException("Invalid version found during commit recovery");
            }

            var iteratorCount = 0;

            try
            {
                iteratorCount = reader.ReadInt32();
            }
            catch { }

            if (iteratorCount > 0)
            {
                Iterators = new Dictionary <string, long>();
                for (int i = 0; i < iteratorCount; i++)
                {
                    Iterators.Add(reader.ReadString(), reader.ReadInt64());
                }
            }

            int  cookieLength   = -1;
            long cookieChecksum = 0;

            if (version >= FasterLogRecoveryVersion)
            {
                try
                {
                    cookieLength = reader.ReadInt32();
                }
                catch { }

                if (cookieLength >= 0)
                {
                    Cookie = reader.ReadBytes(cookieLength);
                    unsafe
                    {
                        fixed(byte *ptr = Cookie)
                        cookieChecksum = (long)Utility.XorBytes(ptr, cookieLength);
                    }
                }
            }

            long computedChecksum = BeginAddress ^ UntilAddress;

            if (version >= FasterLogRecoveryVersion)
            {
                computedChecksum ^= CommitNum ^ iteratorCount ^ cookieLength ^ cookieChecksum;
            }

            // Handle case where all fields are zero
            if (version == 0 && BeginAddress == 0 && UntilAddress == 0 && iteratorCount == 0)
            {
                throw new FasterException("Invalid checksum found during commit recovery");
            }

            if (checkSum != computedChecksum)
            {
                throw new FasterException("Invalid checksum found during commit recovery");
            }
        }