public FileChannel truncate(long newLength) throws IOException {
if (newLength >= length) {
return this;
}
filePointer = Math.min(filePointer, newLength);
int newFileCount = 1 + (int) (newLength / maxLength);
if (newFileCount < list.length) {
// delete some of the files
FileChannel[] newList = new FileChannel[newFileCount];
// delete backwards, so that truncating is somewhat transactional
for (int i = list.length - 1; i >= newFileCount; i--) {
// verify the file is writable
list[i].truncate(0);
list[i].close();
try {
file.getBase(i).delete();
} catch (DbException e) {
throw DbException.convertToIOException(e);
}
}
System.arraycopy(list, 0, newList, 0, newList.length);
list = newList;
}
long size = newLength - maxLength * (newFileCount - 1);
list[list.length - 1].truncate(size);
this.length = newLength;
return this;
}
private ValueLobDb createLob(InputStream in, int type) throws IOException {
byte[] streamStoreId;
try {
streamStoreId = streamStore.put(in);
} catch (Exception e) {
throw DbException.convertToIOException(e);
}
long lobId = generateLobId();
long length = streamStore.length(streamStoreId);
int tableId = LobStorageFrontend.TABLE_TEMP;
Object[] value = new Object[] {streamStoreId, tableId, length, 0};
lobMap.put(lobId, value);
Object[] key = new Object[] {streamStoreId, lobId};
refMap.put(key, Boolean.TRUE);
ValueLobDb lob = ValueLobDb.create(type, database, tableId, lobId, null, length);
if (TRACE) {
trace("create " + tableId + "/" + lobId);
}
return lob;
}
/**
* Store a properties file. The header and the date is not written.
*
* @param fileName the target file name
*/
public synchronized void store(String fileName) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
store(out, null);
ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
InputStreamReader reader = new InputStreamReader(in, "ISO8859-1");
LineNumberReader r = new LineNumberReader(reader);
Writer w;
try {
w = new OutputStreamWriter(IOUtils.openFileOutputStream(fileName, false));
} catch (Exception e) {
throw DbException.convertToIOException(e);
}
PrintWriter writer = new PrintWriter(new BufferedWriter(w));
while (true) {
String line = r.readLine();
if (line == null) {
break;
}
if (!line.startsWith("#")) {
writer.print(line + "\n");
}
}
writer.close();
}
/**
* Run one recovery stage. There are three recovery stages: 0: only the undo steps are run
* (restoring the state before the last checkpoint). 1: the pages that are used by the transaction
* log are allocated. 2: the committed operations are re-applied.
*
* @param stage the recovery stage
* @return whether the transaction log was empty
*/
boolean recover(int stage) {
if (trace.isDebugEnabled()) {
trace.debug("log recover stage: " + stage);
}
if (stage == RECOVERY_STAGE_ALLOCATE) {
PageInputStream in = new PageInputStream(store, logKey, firstTrunkPage, firstDataPage);
usedLogPages = in.allocateAllPages();
in.close();
return true;
}
PageInputStream pageIn = new PageInputStream(store, logKey, firstTrunkPage, firstDataPage);
DataReader in = new DataReader(pageIn);
int logId = 0;
Data data = store.createData();
boolean isEmpty = true;
try {
int pos = 0;
while (true) {
int x = in.readByte();
if (x < 0) {
break;
}
pos++;
isEmpty = false;
if (x == UNDO) {
int pageId = in.readVarInt();
int size = in.readVarInt();
if (size == 0) {
in.readFully(data.getBytes(), store.getPageSize());
} else if (size == 1) {
// empty
Arrays.fill(data.getBytes(), 0, store.getPageSize(), (byte) 0);
} else {
in.readFully(compressBuffer, size);
try {
compress.expand(compressBuffer, 0, size, data.getBytes(), 0, store.getPageSize());
} catch (ArrayIndexOutOfBoundsException e) {
DbException.convertToIOException(e);
}
}
if (stage == RECOVERY_STAGE_UNDO) {
if (!undo.get(pageId)) {
if (trace.isDebugEnabled()) {
trace.debug("log undo {0}", pageId);
}
store.writePage(pageId, data);
undo.set(pageId);
undoAll.set(pageId);
} else {
if (trace.isDebugEnabled()) {
trace.debug("log undo skip {0}", pageId);
}
}
}
} else if (x == ADD) {
int sessionId = in.readVarInt();
int tableId = in.readVarInt();
Row row = readRow(in, data);
if (stage == RECOVERY_STAGE_UNDO) {
store.allocateIfIndexRoot(pos, tableId, row);
} else if (stage == RECOVERY_STAGE_REDO) {
if (isSessionCommitted(sessionId, logId, pos)) {
if (trace.isDebugEnabled()) {
trace.debug("log redo + table: " + tableId + " s: " + sessionId + " " + row);
}
store.redo(tableId, row, true);
} else {
if (trace.isDebugEnabled()) {
trace.debug("log ignore s: " + sessionId + " + table: " + tableId + " " + row);
}
}
}
} else if (x == REMOVE) {
int sessionId = in.readVarInt();
int tableId = in.readVarInt();
long key = in.readVarLong();
if (stage == RECOVERY_STAGE_REDO) {
if (isSessionCommitted(sessionId, logId, pos)) {
if (trace.isDebugEnabled()) {
trace.debug("log redo - table: " + tableId + " s:" + sessionId + " key: " + key);
}
store.redoDelete(tableId, key);
} else {
if (trace.isDebugEnabled()) {
trace.debug("log ignore s: " + sessionId + " - table: " + tableId + " " + key);
}
}
}
} else if (x == TRUNCATE) {
int sessionId = in.readVarInt();
int tableId = in.readVarInt();
if (stage == RECOVERY_STAGE_REDO) {
if (isSessionCommitted(sessionId, logId, pos)) {
if (trace.isDebugEnabled()) {
trace.debug("log redo truncate table: " + tableId);
}
store.redoTruncate(tableId);
} else {
if (trace.isDebugEnabled()) {
trace.debug("log ignore s: " + sessionId + " truncate table: " + tableId);
}
}
}
} else if (x == PREPARE_COMMIT) {
int sessionId = in.readVarInt();
String transaction = in.readString();
if (trace.isDebugEnabled()) {
trace.debug("log prepare commit " + sessionId + " " + transaction + " pos: " + pos);
}
if (stage == RECOVERY_STAGE_UNDO) {
int page = pageIn.getDataPage();
setPrepareCommit(sessionId, page, transaction);
}
} else if (x == ROLLBACK) {
int sessionId = in.readVarInt();
if (trace.isDebugEnabled()) {
trace.debug("log rollback " + sessionId + " pos: " + pos);
}
// ignore - this entry is just informational
} else if (x == COMMIT) {
int sessionId = in.readVarInt();
if (trace.isDebugEnabled()) {
trace.debug("log commit " + sessionId + " pos: " + pos);
}
if (stage == RECOVERY_STAGE_UNDO) {
setLastCommitForSession(sessionId, logId, pos);
}
} else if (x == NOOP) {
// nothing to do
} else if (x == CHECKPOINT) {
logId++;
} else if (x == FREE_LOG) {
int count = in.readVarInt();
for (int i = 0; i < count; i++) {
int pageId = in.readVarInt();
if (stage == RECOVERY_STAGE_REDO) {
if (!usedLogPages.get(pageId)) {
store.free(pageId, false);
}
}
}
} else {
if (trace.isDebugEnabled()) {
trace.debug("log end");
break;
}
}
}
} catch (DbException e) {
if (e.getErrorCode() == ErrorCode.FILE_CORRUPTED_1) {
trace.debug("log recovery stopped");
} else {
throw e;
}
} catch (IOException e) {
trace.debug("log recovery completed");
}
undo = new BitField();
if (stage == RECOVERY_STAGE_REDO) {
usedLogPages = null;
}
return isEmpty;
}