private void _InitResume(IRegionManager regionmgr)
{
this.rootblockstream = regionmgr.readRegionAddr(0).getNewAccessStream();
root = Util.readStruct<RootBlockHeader>(rootblockstream);
if (!root.IsValid()) {
throw new Exception("invalid root block");
}
RootBlockLogSegment[] log_segments = new RootBlockLogSegment[root.num_logsegments];
for (int i=0;i<root.num_logsegments;i++) {
log_segments[i] = Util.readStruct<RootBlockLogSegment>(rootblockstream);
}
// setup the log segment handler
this.log_handler = new LogSegmentsHandler(this,regionmgr, log_segments);
foreach (LogCmd cmd in log_handler.recoverLogCmds()) {
receiver.handleCommand(cmd.cmd, cmd.cmddata);
}
}
// special "init" of a region
private void _InitNewRegion(IRegionManager regionmgr, out int system_reserved_space)
{
// test to see if there is already a root record there
{
try {
Stream testrootblockstream = regionmgr.readRegionAddr(0).getNewAccessStream();
RootBlockHeader nroot = Util.readStruct<RootBlockHeader>(testrootblockstream);
long rtblksz = testrootblockstream.Position;
if (nroot.IsValid()) {
// TODO: we should be careful not to overwrite an existing root record...
// throw new Exception("existing root record present! Can't re-init.");
}
testrootblockstream.Close();
} catch (RegionExposedFiles.RegionMissingException) {
}
}
// (1) initialize the log segments...
RootBlockLogSegment[] log_segments = new RootBlockLogSegment[LogWriter.DEFAULT_LOG_SEGMENTS];
uint nextFreeAddress = RootBlockHeader.ROOTBLOCK_SIZE;
for (int i=0;i<log_segments.Length;i++) {
// calculate the segment start and length
log_segments[i].logsegment_size = LogWriter.DEFAULT_LOG_SEGMENT_SIZE;
log_segments[i].logsegment_start = nextFreeAddress;
nextFreeAddress += LogWriter.DEFAULT_LOG_SEGMENT_SIZE;
// open the segment
Stream logstream = regionmgr.writeFreshRegionAddr(log_segments[i].logsegment_start, log_segments[i].logsegment_size).getNewAccessStream();
// write to the end of the log to be sure the file/stream has enough space
logstream.Seek(log_segments[i].logsegment_size - 1, SeekOrigin.Begin);
logstream.WriteByte(0x00);
logstream.Flush();
logstream.Seek(0, SeekOrigin.Begin);
LogSegmentsHandler.InitLogSegmentStream(logstream);
// write the initial "log-end" record at the beginning of the segment
logstream.Close();
}
root.magic = RootBlockHeader.ROOTMAGIC;
root.root_checksum = 0;
byte[] root_block_data = root.constructRootBlock(log_segments);
// open the streams...
Stream rootblockwritestream = regionmgr.writeFreshRegionAddr(0, (long)RootBlockHeader.ROOTBLOCK_SIZE).getNewAccessStream();
// this.logstream = logwritestream;
this.rootblockstream = rootblockwritestream;
// now write the root record
rootblockstream.Seek(0, SeekOrigin.Begin);
rootblockstream.Write(root_block_data,0,root_block_data.Length);
rootblockstream.Flush();
rootblockstream.Close(); // must close the stream so resume can operate
system_reserved_space = (int)nextFreeAddress;
}