1 files changed, 234 insertions, 0 deletions
diff --git a/storage/test/gtest/test_unlock_notify.cpp b/storage/test/gtest/test_unlock_notify.cpp
new file mode 100644
index 0000000000..93cc5b09a8
--- /dev/null
+++ b/storage/test/gtest/test_unlock_notify.cpp
@@ -0,0 +1,234 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim set:sw=2 ts=2 et lcs=trail\:.,tab\:>~ : */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "storage_test_harness.h"
+
+#include "mozilla/ReentrantMonitor.h"
+#include "nsThreadUtils.h"
+#include "mozIStorageStatement.h"
+
+/**
+ * This file tests that our implementation around sqlite3_unlock_notify works
+ * as expected.
+ */
+
+////////////////////////////////////////////////////////////////////////////////
+//// Helpers
+
+enum State { STARTING, WRITE_LOCK, READ_LOCK, TEST_DONE };
+
+class DatabaseLocker : public mozilla::Runnable {
+ public:
+  explicit DatabaseLocker(const char* aSQL, nsIFile* aDBFile = nullptr)
+      : mozilla::Runnable("DatabaseLocker"),
+        monitor("DatabaseLocker::monitor"),
+        mSQL(aSQL),
+        mState(STARTING),
+        mDBFile(aDBFile) {}
+
+  void RunInBackground() {
+    (void)NS_NewNamedThread("DatabaseLocker", getter_AddRefs(mThread));
+    do_check_true(mThread);
+
+    do_check_success(mThread->Dispatch(this, NS_DISPATCH_NORMAL));
+  }
+
+  void Shutdown() {
+    if (mThread) {
+      mThread->Shutdown();
+    }
+  }
+
+  NS_IMETHOD Run() override {
+    mozilla::ReentrantMonitorAutoEnter lock(monitor);
+
+    nsCOMPtr<mozIStorageConnection> db(getDatabase(mDBFile));
+
+    nsCString sql(mSQL);
+    nsCOMPtr<mozIStorageStatement> stmt;
+    do_check_success(db->CreateStatement(sql, getter_AddRefs(stmt)));
+
+    bool hasResult;
+    do_check_success(stmt->ExecuteStep(&hasResult));
+
+    Notify(WRITE_LOCK);
+    WaitFor(TEST_DONE);
+
+    return NS_OK;
+  }
+
+  void WaitFor(State aState) {
+    monitor.AssertCurrentThreadIn();
+    while (mState != aState) {
+      do_check_success(monitor.Wait());
+    }
+  }
+
+  void Notify(State aState) {
+    monitor.AssertCurrentThreadIn();
+    mState = aState;
+    do_check_success(monitor.Notify());
+  }
+
+  mozilla::ReentrantMonitor monitor MOZ_UNANNOTATED;
+
+ protected:
+  nsCOMPtr<nsIThread> mThread;
+  const char* const mSQL;
+  State mState;
+  nsCOMPtr<nsIFile> mDBFile;
+};
+
+class DatabaseTester : public DatabaseLocker {
+ public:
+  DatabaseTester(mozIStorageConnection* aConnection, const char* aSQL)
+      : DatabaseLocker(aSQL), mConnection(aConnection) {}
+
+  NS_IMETHOD Run() override {
+    mozilla::ReentrantMonitorAutoEnter lock(monitor);
+    WaitFor(READ_LOCK);
+
+    nsCString sql(mSQL);
+    nsCOMPtr<mozIStorageStatement> stmt;
+    do_check_success(mConnection->CreateStatement(sql, getter_AddRefs(stmt)));
+
+    bool hasResult;
+    nsresult rv = stmt->ExecuteStep(&hasResult);
+    do_check_eq(rv, NS_ERROR_FILE_IS_LOCKED);
+
+    // Finalize our statement and null out our connection before notifying to
+    // ensure that we close on the proper thread.
+    rv = stmt->Finalize();
+    do_check_eq(rv, NS_ERROR_FILE_IS_LOCKED);
+    mConnection = nullptr;
+
+    Notify(TEST_DONE);
+
+    return NS_OK;
+  }
+
+ private:
+  nsCOMPtr<mozIStorageConnection> mConnection;
+};
+
+////////////////////////////////////////////////////////////////////////////////
+//// Test Functions
+
+void setup() {
+  nsCOMPtr<mozIStorageConnection> db(getDatabase());
+
+  // Create and populate a dummy table.
+  nsresult rv = db->ExecuteSimpleSQL(nsLiteralCString(
+      "CREATE TABLE test (id INTEGER PRIMARY KEY, data STRING)"));
+  do_check_success(rv);
+  rv = db->ExecuteSimpleSQL("INSERT INTO test (data) VALUES ('foo')"_ns);
+  do_check_success(rv);
+  rv = db->ExecuteSimpleSQL("INSERT INTO test (data) VALUES ('bar')"_ns);
+  do_check_success(rv);
+  rv =
+      db->ExecuteSimpleSQL("CREATE UNIQUE INDEX unique_data ON test (data)"_ns);
+  do_check_success(rv);
+}
+
+void test_step_locked_does_not_block_main_thread() {
+  nsCOMPtr<mozIStorageConnection> db(getDatabase());
+
+  // Need to prepare our statement ahead of time so we make sure to only test
+  // step and not prepare.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv = db->CreateStatement(
+      "INSERT INTO test (data) VALUES ('test1')"_ns, getter_AddRefs(stmt));
+  do_check_success(rv);
+
+  nsCOMPtr<nsIFile> dbFile;
+  db->GetDatabaseFile(getter_AddRefs(dbFile));
+  RefPtr<DatabaseLocker> locker(
+      new DatabaseLocker("SELECT * FROM test", dbFile));
+  do_check_true(locker);
+  {
+    mozilla::ReentrantMonitorAutoEnter lock(locker->monitor);
+    locker->RunInBackground();
+
+    // Wait for the locker to notify us that it has locked the database
+    // properly.
+    locker->WaitFor(WRITE_LOCK);
+
+    bool hasResult;
+    rv = stmt->ExecuteStep(&hasResult);
+    do_check_eq(rv, NS_ERROR_FILE_IS_LOCKED);
+
+    locker->Notify(TEST_DONE);
+  }
+  locker->Shutdown();
+}
+
+void test_drop_index_does_not_loop() {
+  nsCOMPtr<mozIStorageConnection> db(getDatabase());
+
+  // Need to prepare our statement ahead of time so we make sure to only test
+  // step and not prepare.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv =
+      db->CreateStatement("SELECT * FROM test"_ns, getter_AddRefs(stmt));
+  do_check_success(rv);
+
+  RefPtr<DatabaseTester> tester =
+      new DatabaseTester(db, "DROP INDEX unique_data");
+  do_check_true(tester);
+  {
+    mozilla::ReentrantMonitorAutoEnter lock(tester->monitor);
+    tester->RunInBackground();
+
+    // Hold a read lock on the database, and then let the tester try to execute.
+    bool hasResult;
+    rv = stmt->ExecuteStep(&hasResult);
+    do_check_success(rv);
+    do_check_true(hasResult);
+    tester->Notify(READ_LOCK);
+
+    // Make sure the tester finishes its test before we move on.
+    tester->WaitFor(TEST_DONE);
+  }
+  tester->Shutdown();
+}
+
+void test_drop_table_does_not_loop() {
+  nsCOMPtr<mozIStorageConnection> db(getDatabase());
+
+  // Need to prepare our statement ahead of time so we make sure to only test
+  // step and not prepare.
+  nsCOMPtr<mozIStorageStatement> stmt;
+  nsresult rv =
+      db->CreateStatement("SELECT * FROM test"_ns, getter_AddRefs(stmt));
+  do_check_success(rv);
+
+  RefPtr<DatabaseTester> tester(new DatabaseTester(db, "DROP TABLE test"));
+  do_check_true(tester);
+  {
+    mozilla::ReentrantMonitorAutoEnter lock(tester->monitor);
+    tester->RunInBackground();
+
+    // Hold a read lock on the database, and then let the tester try to execute.
+    bool hasResult;
+    rv = stmt->ExecuteStep(&hasResult);
+    do_check_success(rv);
+    do_check_true(hasResult);
+    tester->Notify(READ_LOCK);
+
+    // Make sure the tester finishes its test before we move on.
+    tester->WaitFor(TEST_DONE);
+  }
+  tester->Shutdown();
+}
+
+TEST(storage_unlock_notify, Test)
+{
+  // These must execute in order.
+  setup();
+  test_step_locked_does_not_block_main_thread();
+  test_drop_index_does_not_loop();
+  test_drop_table_does_not_loop();
+}