Skip to content

H
h2database
提交 799303c9 authored 作者: Thomas Mueller's avatar Thomas Mueller
浏览文件
操作

Issue 315: Access to LOBs could cause a Java level deadlock.

上级 2bddbdf2
显示空白字符变更
内嵌 并排
正在显示 包含 235 行增加 和 178 行删除
h2/src/docsrc/html/changelog.html
浏览文件 @ 799303c9
......@@ -17,7 +17,8 @@ Change Log
<h1>Change Log</h1>
<h2>Next Version (unreleased)</h2>
<ul><li>Support for the ICU4J collator.
<ul><li>Issue 315: Access to LOBs could cause a Java level deadlock.
</li><li>Support for the ICU4J collator.
</li><li>Improved Oracle compatibility: support for NVL2. Thanks to litailang for the patch!
</li><li>Improved PostgreSQL compatibility: support for RANDOM() in addition to RAND().
</li><li>There was a classloader memory leak problem because a class contained a static
......
h2/src/main/org/h2/store/LobStorage.java
浏览文件 @ 799303c9
......@@ -80,10 +80,11 @@ public class LobStorage {
/**
* Initialize the lob storage.
*/
public synchronized void init() {
public void init() {
if (init) {
return;
}
synchronized (handler) {
conn = handler.getLobConnection();
init = true;
if (conn == null) {
......@@ -107,6 +108,7 @@ public class LobStorage {
throw DbException.convert(e);
}
}
}
private long getNextLobId() throws SQLException {
String sql = "SELECT MAX(LOB) FROM " + LOB_MAP;
......@@ -173,42 +175,43 @@ public class LobStorage {
return ValueLob.createSmallLob(type, small);
}
byte[] readBlock(long lob, int seq) throws SQLException {
synchronized (handler) {
String sql = "SELECT COMPRESSED, DATA FROM " + LOB_MAP + " M " +
"INNER JOIN " + LOB_DATA + " D ON M.BLOCK = D.BLOCK " +
"WHERE M.LOB = ? AND M.SEQ = ?";
PreparedStatement prep = prepare(sql);
prep.setLong(1, lob);
prep.setInt(2, seq);
ResultSet rs = prep.executeQuery();
if (!rs.next()) {
throw DbException.get(ErrorCode.IO_EXCEPTION_1, "Missing lob entry: "+ lob + "/" + seq).getSQLException();
}
int compressed = rs.getInt(1);
byte[] buffer = rs.getBytes(2);
if (compressed != 0) {
buffer = compress.expand(buffer);
}
reuse(sql, prep);
return buffer;
}
}
/**
* An input stream that reads from a LOB.
*/
public static class LobInputStream extends InputStream {
public class LobInputStream extends InputStream {
private final Connection conn;
private PreparedStatement prepSelect;
private byte[] buffer;
private int pos;
private long remainingBytes;
private long lob;
private int seq;
private CompressTool compress;
public LobInputStream(Connection conn, long lob, long byteCount) throws IOException {
this.conn = conn;
this.lob = lob;
if (byteCount == -1) {
try {
public LobInputStream(long lob, long byteCount) {
this.lob = lob;
PreparedStatement prep = conn.prepareStatement(
"SELECT BYTE_COUNT FROM " + LOBS + " WHERE ID = ?");
prep.setLong(1, lob);
ResultSet rs = prep.executeQuery();
if (!rs.next()) {
throw DbException.get(ErrorCode.IO_EXCEPTION_1, "Missing lob: "+ lob).getSQLException();
}
remainingBytes = rs.getLong(1);
rs.close();
} catch (SQLException e) {
throw DbException.convertToIOException(e);
}
} else {
remainingBytes = byteCount;
}
}
public int read() throws IOException {
fillBuffer();
......@@ -257,27 +260,7 @@ public class LobStorage {
return;
}
try {
if (prepSelect == null) {
prepSelect = conn.prepareStatement(
"SELECT COMPRESSED, DATA FROM " + LOB_MAP + " M " +
"INNER JOIN " + LOB_DATA + " D ON M.BLOCK = D.BLOCK " +
"WHERE M.LOB = ? AND M.SEQ = ?");
}
prepSelect.setLong(1, lob);
prepSelect.setInt(2, seq);
ResultSet rs = prepSelect.executeQuery();
if (!rs.next()) {
throw DbException.get(ErrorCode.IO_EXCEPTION_1, "Missing lob entry: "+ lob + "/" + seq).getSQLException();
}
seq++;
int compressed = rs.getInt(1);
buffer = rs.getBytes(2);
if (compressed != 0) {
if (compress == null) {
compress = CompressTool.getInstance();
}
buffer = compress.expand(buffer);
}
buffer = readBlock(lob, seq++);
pos = 0;
} catch (SQLException e) {
throw DbException.convertToIOException(e);
......@@ -286,7 +269,12 @@ public class LobStorage {
}
private synchronized PreparedStatement prepare(String sql) throws SQLException {
private PreparedStatement prepare(String sql) throws SQLException {
if (SysProperties.CHECK2) {
if (!Thread.holdsLock(handler)) {
throw DbException.throwInternalError();
}
}
PreparedStatement prep = prepared.remove(sql);
if (prep == null) {
prep = conn.prepareStatement(sql);
......@@ -294,11 +282,17 @@ public class LobStorage {
return prep;
}
private synchronized void reuse(String sql, PreparedStatement prep) {
private void reuse(String sql, PreparedStatement prep) {
if (SysProperties.CHECK2) {
if (!Thread.holdsLock(handler)) {
throw DbException.throwInternalError();
}
}
prepared.put(sql, prep);
}
private synchronized void deleteLob(long lob) throws SQLException {
private void deleteLob(long lob) throws SQLException {
synchronized (handler) {
String sql = "SELECT BLOCK, HASH FROM " + LOB_MAP + " D WHERE D.LOB = ? " +
"AND NOT EXISTS(SELECT 1 FROM " + LOB_MAP + " O " +
"WHERE O.BLOCK = D.BLOCK AND O.LOB <> ?)";
......@@ -334,6 +328,7 @@ public class LobStorage {
prep.execute();
reuse(sql, prep);
}
}
/**
* Get the input stream for the given lob.
......@@ -344,7 +339,24 @@ public class LobStorage {
*/
public InputStream getInputStream(long lobId, long byteCount) throws IOException {
init();
return new LobInputStream(conn, lobId, byteCount);
if (byteCount == -1) {
synchronized (handler) {
try {
String sql = "SELECT BYTE_COUNT FROM " + LOBS + " WHERE ID = ?";
PreparedStatement prep = prepare(sql);
prep.setLong(1, lobId);
ResultSet rs = prep.executeQuery();
if (!rs.next()) {
throw DbException.get(ErrorCode.IO_EXCEPTION_1, "Missing lob: "+ lobId).getSQLException();
}
byteCount = rs.getLong(1);
reuse(sql, prep);
} catch (SQLException e) {
throw DbException.convertToIOException(e);
}
}
}
return new LobInputStream(lobId, byteCount);
}
private ValueLobDb addLob(InputStream in, long maxLength, int type) {
......@@ -378,7 +390,7 @@ public class LobStorage {
small = b;
break;
}
synchronized (this) {
synchronized (handler) {
if (seq == 0) {
lobId = getNextLobId();
}
......@@ -407,6 +419,7 @@ public class LobStorage {
}
private ValueLobDb registerLob(int type, long lobId, int tableId, long byteCount) {
synchronized (handler) {
try {
String sql = "INSERT INTO " + LOBS + "(ID, BYTE_COUNT, TABLE) VALUES(?, ?, ?)";
PreparedStatement prep = prepare(sql);
......@@ -421,6 +434,7 @@ public class LobStorage {
throw DbException.convert(e);
}
}
}
/**
* Copy a lob.
......@@ -431,7 +445,8 @@ public class LobStorage {
* @param length the length
* @return the new lob
*/
public synchronized ValueLobDb copyLob(int type, long oldLobId, int tableId, long length) {
public ValueLobDb copyLob(int type, long oldLobId, int tableId, long length) {
synchronized (handler) {
try {
init();
long lobId = getNextLobId();
......@@ -458,6 +473,7 @@ public class LobStorage {
throw DbException.convert(e);
}
}
}
private long getHashCacheBlock(int hash) {
if (HASH_CACHE_SIZE > 0) {
......@@ -486,13 +502,14 @@ public class LobStorage {
* @param b the data
* @param compressAlgorithm the compression algorithm (may be null)
*/
synchronized void storeBlock(long lobId, int seq, byte[] b, String compressAlgorithm) throws SQLException {
void storeBlock(long lobId, int seq, byte[] b, String compressAlgorithm) throws SQLException {
long block;
boolean blockExists = false;
if (compressAlgorithm != null) {
b = compress.compress(b, compressAlgorithm);
}
int hash = Arrays.hashCode(b);
synchronized (handler) {
block = getHashCacheBlock(hash);
if (block != -1) {
String sql = "SELECT COMPRESSED, DATA FROM " + LOB_DATA +
......@@ -529,6 +546,7 @@ public class LobStorage {
prep.execute();
reuse(sql, prep);
}
}
/**
* An input stream that reads the data from a reader.
......@@ -651,6 +669,7 @@ public class LobStorage {
* @param table the table
*/
public void setTable(long lobId, int table) {
synchronized (handler) {
try {
init();
String sql = "UPDATE " + LOBS + " SET TABLE = ? WHERE ID = ?";
......@@ -663,5 +682,6 @@ public class LobStorage {
throw DbException.convert(e);
}
}
}
}
h2/src/test/org/h2/test/db/TestLob.java
浏览文件 @ 799303c9
......@@ -54,6 +54,7 @@ public class TestLob extends TestBase {
}
public void test() throws Exception {
testDeadlock();
testCopyManyLobs();
testCopyLob();
testConcurrentCreate();
......@@ -95,6 +96,41 @@ public class TestLob extends TestBase {
IOUtils.deleteRecursive(TEMP_DIR, true);
}
/**
* Test for issue 315: Java Level Deadlock on Database & Session Objects
*/
private void testDeadlock() throws Exception {
deleteDb("lob");
Connection conn = getConnection("lob");
Statement stat = conn.createStatement();
stat.execute("create table test(id int primary key, name clob)");
stat.execute("insert into test select x, space(10000) from system_range(1, 3)");
final Connection conn2 = getConnection("lob");
Task task = new Task() {
public void call() throws Exception {
Statement stat = conn2.createStatement();
stat.setFetchSize(1);
for (int i = 0; !stop; i++) {
ResultSet rs = stat.executeQuery("select * from test where id > -" + i);
while (rs.next()) {
// ignore
}
}
}
};
task.execute();
stat.execute("create table test2(id int primary key, name clob)");
for (int i = 0; i < 1000; i++) {
stat.execute("delete from test2");
stat.execute("insert into test2 values(1, space(10000 + " + i + "))");
}
task.get();
conn.close();
conn2.close();
}
private void testCopyManyLobs() throws Exception {
deleteDb("lob");
Connection conn = getConnection("lob");
......
Markdown 格式
0% 或
您添加了 0 人 到此讨论。请谨慎行事。
请先完成此评论的编辑！
请 注册 或者 后发表评论