AdvancedLauncher.SDK.Management.FileSystemManager.Open C# (CSharp) Method

        public bool Open(FileAccess access, int archiveHeader, string headerFile, string packageFile)
        {
            if (LogManager != null) {
                LogManager.DebugFormat("Opening FileSystem: access={0}, archiveHeader={1}, headerFile={2}, packageFile={3}",
                    access, archiveHeader, headerFile, packageFile);
            }
            if (_IsOpened) {
                return false;
            }

            if (!File.Exists(headerFile) || !File.Exists(packageFile)) {
                if (LogManager != null) {
                    LogManager.Error("FileSystem open failed (FileNotFoundException)");
                }
                throw new FileNotFoundException();
            }
            if (IsFileLocked(headerFile) || IsFileLocked(packageFile)) {
                if (LogManager != null) {
                    LogManager.Error("FileSystem open failed (UnauthorizedAccessException)");
                }
                throw new UnauthorizedAccessException();
            }

            this.Access = access;
            this.ArchiveHeader = archiveHeader;
            this.HeaderFile = headerFile;
            this.PackageFile = packageFile;
            this.ArchiveEntries.Clear();

            using (BinaryReader reader = new BinaryReader(File.OpenRead(headerFile), Encoding.Default)) {
                if (reader.ReadUInt32() != archiveHeader) {
                    if (LogManager != null) {
                        LogManager.Error("FileSystem open failed (FileFormatException)");
                    }
                    throw new FileFormatException();
                }

                uint entryCount = reader.ReadUInt32();
                FileEntry entry;

                for (uint e = 0; e < entryCount; e++) {
                    entry = new FileEntry();
                    if (reader.ReadUInt32() != 1) {
                        if (LogManager != null) {
                            LogManager.Error("FileSystem open failed (FileFormatException)");
                        }
                        throw new FileFormatException();
                    }

                    entry.SizeCurrent = reader.ReadUInt32();
                    entry.SizeAvailable = reader.ReadUInt32();
                    entry.Id = reader.ReadUInt32();
                    entry.Offset = reader.ReadInt64();

                    ArchiveEntries.Add(entry);
                }
            }

            if (access == FileAccess.ReadWrite || access == FileAccess.Write) {
                try {
                    MapWriter = new BinaryWriter(File.Open(HeaderFile, FileMode.OpenOrCreate, access, FileShare.None));
                    ArchiveStream = File.Open(PackageFile, FileMode.OpenOrCreate, access, FileShare.None);
                } catch {
                    throw;
                }
            }

            _IsOpened = true;
            return true;
        }