/**
* Something is wrong with this file. If there is no data in this file (the header is <= the file
* header size) then move this last file aside and search the next "last" file. If the last file
* does have data in it, return null and throw an exception back to the application, since we're
* not sure what to do now.
*
* @param cause is a DatabaseException or ChecksumException.
*/
private Long attemptToMoveBadFile(Exception cause)
throws IOException, ChecksumException, DatabaseException {
String fileName = fileManager.getFullFileNames(window.currentFileNum())[0];
File problemFile = new File(fileName);
if (problemFile.length() <= FileManager.firstLogEntryOffset()) {
fileManager.clear(); // close all existing files
/* Move this file aside. */
Long lastNum = fileManager.getFollowingFileNum(window.currentFileNum(), false);
if (!fileManager.renameFile(window.currentFileNum(), FileManager.BAD_SUFFIX)) {
throw EnvironmentFailureException.unexpectedState(
"Could not rename file: 0x" + Long.toHexString(window.currentFileNum()));
}
return lastNum;
}
/* There's data in this file, throw up to the app. */
if (cause instanceof DatabaseException) {
throw (DatabaseException) cause;
}
if (cause instanceof ChecksumException) {
throw (ChecksumException) cause;
}
throw EnvironmentFailureException.unexpectedException(cause);
}
/** Override so that we always start at the last file. */
protected void initStartingPosition(long endOfFileLsn, Long singleFileNum)
throws IOException, DatabaseException {
eof = false;
/*
* Start at what seems like the last file. If it doesn't exist, we're
* done.
*/
Long lastNum =
((singleFileNum != null) && (singleFileNum.longValue() >= 0))
? singleFileNum
: fileManager.getLastFileNum();
FileHandle fileHandle = null;
readBufferFileEnd = 0;
long fileLen = 0;
while ((fileHandle == null) && !eof) {
if (lastNum == null) {
eof = true;
} else {
try {
readBufferFileNum = lastNum.longValue();
fileHandle = fileManager.getFileHandle(readBufferFileNum);
/*
* Check the size of this file. If it opened successfully
* but only held a header or is 0 length, backup to the
* next "last" file unless this is the only file in the
* log. Note that an incomplete header will end up throwing
* a checksum exception, but a 0 length file will open
* successfully in read only mode.
*/
fileLen = fileHandle.getFile().length();
if (fileLen <= FileManager.firstLogEntryOffset()) {
lastNum = fileManager.getFollowingFileNum(lastNum.longValue(), false);
if (lastNum != null) {
fileHandle.release();
fileHandle = null;
}
}
} catch (DatabaseException e) {
lastNum = attemptToMoveBadFile(e);
fileHandle = null;
} finally {
if (fileHandle != null) {
fileHandle.release();
}
}
}
}
nextEntryOffset = 0;
}
/**
* Something is wrong with this file. If there is no data in this file (the header is <= the file
* header size) then move this last file aside and search the next "last" file. If the last file
* does have data in it, throw an exception back to the application, since we're not sure what to
* do now.
*/
private Long attemptToMoveBadFile(DatabaseException origException)
throws DatabaseException, IOException {
String fileName = fileManager.getFullFileNames(readBufferFileNum)[0];
File problemFile = new File(fileName);
Long lastNum = null;
if (problemFile.length() <= FileManager.firstLogEntryOffset()) {
fileManager.clear(); // close all existing files
/* Move this file aside. */
lastNum = fileManager.getFollowingFileNum(readBufferFileNum, false);
fileManager.renameFile(readBufferFileNum, FileManager.BAD_SUFFIX);
} else {
/* There's data in this file, throw up to the app. */
throw origException;
}
return lastNum;
}
public void testTruncatedHeader() throws IOException, DatabaseException {
/* Create a log file */
FileManagerTestUtils.createLogFile(fileManager, envImpl, FILE_SIZE);
/* Truncate the header */
RandomAccessFile file0 =
new RandomAccessFile(
fileManager.getFullFileName(0, FileManager.JE_SUFFIX),
FileManager.FileMode.READWRITE_MODE.getModeValue());
file0.getChannel().truncate(FileManager.firstLogEntryOffset() / 2);
file0.close();
try {
fileManager.getFileHandle(0);
fail("Should see assertion");
} catch (DatabaseException e) {
}
}
/** Test initializing the last position in the logs. */
public void testSetLastPosition() throws DatabaseException {
/*
* Pretend that the last file is file 79.
*/
fileManager.setLastPosition( // next available LSN
DbLsn.makeLsn(79L, 88L), DbLsn.makeLsn(79L, 77), 66L);
/* Put an entry down, should fit within file 79. */
fileManager.bumpLsn(11L);
assertEquals(DbLsn.makeLsn(79L, 88L), fileManager.getLastUsedLsn());
assertEquals(77L, fileManager.getPrevEntryOffset());
/* Put another entry in, should go to the next file. */
fileManager.bumpLsn(22L);
assertEquals(
DbLsn.makeLsn(80L, FileManager.firstLogEntryOffset()), fileManager.getLastUsedLsn());
assertEquals(0, fileManager.getPrevEntryOffset());
}
/** See if we can catch a file with an invalid header. */
public void testBadHeader() throws IOException, DatabaseException {
/* First try a bad environment r/w. */
try {
FileManager test = new FileManager(envImpl, new File("xxyy"), true);
fail("expect creation of " + test + "to fail.");
} catch (LogException e) {
/* should throw */
}
/* Next try a bad environment r/o. */
try {
FileManager test = new FileManager(envImpl, new File("xxyy"), false);
fail("expect creation of " + test + "to fail.");
} catch (DatabaseException e) {
/* should throw */
}
/* Now create a file, but mess up the header. */
FileManagerTestUtils.createLogFile(fileManager, envImpl, FILE_SIZE);
byte[] badData = new byte[] {1, 1};
int headerSize = FileManager.firstLogEntryOffset();
RandomAccessFile file0 =
new RandomAccessFile(
fileManager.getFullFileName(0, FileManager.JE_SUFFIX),
FileManager.FileMode.READWRITE_MODE.getModeValue());
file0.write(badData);
file0.close();
fileManager.clear();
try {
FileHandle file0Handle = fileManager.getFileHandle(0L);
fail("expect to catch a checksum error");
} catch (DbChecksumException e) {
}
}
/** Initialize starting position to the last file with a complete header with a valid checksum. */
private void startAtLastGoodFile(Long singleFileNum) throws ChecksumException {
eof = false;
window.initAtFileStart(DbLsn.makeLsn(0, 0));
/*
* Start at what seems like the last file. If it doesn't exist, we're
* done.
*/
Long lastNum =
((singleFileNum != null) && (singleFileNum.longValue() >= 0))
? singleFileNum
: fileManager.getLastFileNum();
FileHandle fileHandle = null;
long fileLen = 0;
while ((fileHandle == null) && !eof) {
if (lastNum == null) {
eof = true;
} else {
try {
try {
window.initAtFileStart(DbLsn.makeLsn(lastNum, 0));
fileHandle = fileManager.getFileHandle(lastNum);
/*
* Check the size of this file. If it opened
* successfully but only held a header or is 0 length,
* backup to the next "last" file unless this is the
* only file in the log. Note that an incomplete header
* will end up throwing a checksum exception, but a 0
* length file will open successfully in read only
* mode.
*/
fileLen = fileHandle.getFile().length();
if (fileLen <= FileManager.firstLogEntryOffset()) {
lastNum = fileManager.getFollowingFileNum(lastNum, false);
if (lastNum != null) {
fileHandle.release();
fileHandle = null;
}
}
} catch (DatabaseException e) {
lastNum = attemptToMoveBadFile(e);
fileHandle = null;
} catch (ChecksumException e) {
lastNum = attemptToMoveBadFile(e);
fileHandle = null;
} finally {
if (fileHandle != null) {
fileHandle.release();
}
}
} catch (IOException e) {
throw new EnvironmentFailureException(envImpl, EnvironmentFailureReason.LOG_READ, e);
}
}
}
nextEntryOffset = 0;
}
/** Test LSN administration. */
public void testLsnBumping() throws Exception {
/*
We are adding these entries:
+----+------+---------+--------+
file 0: |hdr | 30 | 50 |empty |
+----+------+---------+--------+
0 hdr hdr+30 hdr+80 99
+----+--------+-------+-------+-----+-------+
file 1: |hdr | 40 | 20 | 10 | 5 | empty |
+----+--------+-------+-------+-----+-------+
0 hdr hdr+40 hdr+60 hdr+70 hdr+75
+-----+-----+--------+
file 2: | hdr | 75 | empty |
+-----+-----+--------+
0 hdr hdr+75
+-----+-------------------------------+
file 3: | hdr | 125 |
+-----+-------------------------------+
0 hdr
+-----+-----+------+-----+--------------+
file 4: | hdr | 10 | 20 | 30 | empty
+-----+-----+------+-----+--------------+
0 hdr hdr+10 hdr+30
*/
try {
/* Should start out at LSN 0. */
/* "add" some entries to the log. */
long hdrSize = FileManager.firstLogEntryOffset();
fileManager.bumpLsn(30L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(0, hdrSize), fileManager.getLastUsedLsn());
/* prev entry. */
assertEquals(0, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(50L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(0, (hdrSize + 30)), fileManager.getLastUsedLsn());
assertEquals(hdrSize, fileManager.getPrevEntryOffset());
/* bump over to a file 1. */
fileManager.bumpLsn(40L);
/* item placed here. */
assertEquals(DbLsn.makeLsn(1, hdrSize), fileManager.getLastUsedLsn());
assertEquals(0, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(20L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(1, (hdrSize + 40)), fileManager.getLastUsedLsn());
assertEquals(hdrSize, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(10L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(1, (hdrSize + 60)), fileManager.getLastUsedLsn());
assertEquals(hdrSize + 40, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(5L);
/* item placed here. */
assertEquals(DbLsn.makeLsn(1, (hdrSize + 70)), fileManager.getLastUsedLsn());
assertEquals(hdrSize + 60, fileManager.getPrevEntryOffset());
/* bump over to file 2. */
fileManager.bumpLsn(75L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(2, hdrSize), fileManager.getLastUsedLsn());
assertEquals(0, fileManager.getPrevEntryOffset());
/* Ask for something bigger than a file: bump over to file 3. */
fileManager.bumpLsn(125L);
/* item placed here. */
assertEquals(DbLsn.makeLsn(3, hdrSize), fileManager.getLastUsedLsn());
assertEquals(0, fileManager.getPrevEntryOffset());
/* bump over to file 4. */
fileManager.bumpLsn(10L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(4, hdrSize), fileManager.getLastUsedLsn());
assertEquals(0, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(20L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(4, (hdrSize + 10)), fileManager.getLastUsedLsn());
assertEquals(hdrSize, fileManager.getPrevEntryOffset());
fileManager.bumpLsn(30L);
/* Item placed here. */
assertEquals(DbLsn.makeLsn(4, (hdrSize + 30)), fileManager.getLastUsedLsn());
assertEquals((hdrSize + 10), fileManager.getPrevEntryOffset());
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
