/** {@inheritDoc} */
public void validateBlockMetadata(Block b) throws IOException {
DatanodeBlockInfo info = volumeMap.get(b);
if (info == null) {
throw new IOException("Block " + b + " does not exist in volumeMap.");
}
FSVolume v = info.getVolume();
File tmp = v.getTmpFile(b);
File f = getFile(b);
if (f == null) {
f = tmp;
}
if (f == null) {
throw new IOException("Block " + b + " does not exist on disk.");
}
if (!f.exists()) {
throw new IOException("Block " + b + " block file " + f + " does not exist on disk.");
}
if (b.getNumBytes() != f.length()) {
throw new IOException(
"Block "
+ b
+ " length is "
+ b.getNumBytes()
+ " does not match block file length "
+ f.length());
}
File meta = getMetaFile(f, b);
if (meta == null) {
throw new IOException("Block " + b + " metafile does not exist.");
}
if (!meta.exists()) {
throw new IOException("Block " + b + " metafile " + meta + " does not exist on disk.");
}
if (meta.length() == 0) {
throw new IOException("Block " + b + " metafile " + meta + " is empty.");
}
long stamp = parseGenerationStamp(f, meta);
if (stamp != b.getGenerationStamp()) {
throw new IOException(
"Block "
+ b
+ " genstamp is "
+ b.getGenerationStamp()
+ " does not match meta file stamp "
+ stamp);
}
}
/** Returns handles to the block file and its metadata file */
public synchronized BlockInputStreams getTmpInputStreams(Block b, long blkOffset, long ckoff)
throws IOException {
DatanodeBlockInfo info = volumeMap.get(b);
if (info == null) {
throw new IOException("Block " + b + " does not exist in volumeMap.");
}
FSVolume v = info.getVolume();
File blockFile = v.getTmpFile(b);
RandomAccessFile blockInFile = new RandomAccessFile(blockFile, "r");
if (blkOffset > 0) {
blockInFile.seek(blkOffset);
}
File metaFile = getMetaFile(blockFile, b);
RandomAccessFile metaInFile = new RandomAccessFile(metaFile, "r");
if (ckoff > 0) {
metaInFile.seek(ckoff);
}
return new BlockInputStreams(
new FileInputStream(blockInFile.getFD()), new FileInputStream(metaInFile.getFD()));
}
/** Sets the offset in the block to which the the next write will write data to. */
public void setChannelPosition(Block b, BlockWriteStreams streams, long dataOffset, long ckOffset)
throws IOException {
long size = 0;
synchronized (this) {
FSVolume vol = volumeMap.get(b).getVolume();
size = vol.getTmpFile(b).length();
}
if (size < dataOffset) {
String msg =
"Trying to change block file offset of block "
+ b
+ " to "
+ dataOffset
+ " but actual size of file is "
+ size;
throw new IOException(msg);
}
FileOutputStream file = (FileOutputStream) streams.dataOut;
file.getChannel().position(dataOffset);
file = (FileOutputStream) streams.checksumOut;
file.getChannel().position(ckOffset);
}