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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=2 sts=2 expandtab
* 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 "StorageBaseStatementInternal.h"
#include "nsProxyRelease.h"
#include "mozStorageBindingParamsArray.h"
#include "mozStorageStatementData.h"
#include "mozStorageAsyncStatementExecution.h"
namespace mozilla {
namespace storage {
////////////////////////////////////////////////////////////////////////////////
//// Local Classes
/**
* Used to finalize an asynchronous statement on the background thread.
*/
class AsyncStatementFinalizer : public Runnable {
public:
/**
* Constructor for the event.
*
* @param aStatement
* We need the AsyncStatement to be able to get at the sqlite3_stmt;
* we only access/create it on the async thread.
* @param aConnection
* We need the connection to know what thread to release the statement
* on. We release the statement on that thread since releasing the
* statement might end up releasing the connection too.
*/
AsyncStatementFinalizer(StorageBaseStatementInternal* aStatement,
Connection* aConnection)
: Runnable("storage::AsyncStatementFinalizer"),
mStatement(aStatement),
mConnection(aConnection) {}
NS_IMETHOD Run() override {
if (mStatement->mAsyncStatement) {
sqlite3_finalize(mStatement->mAsyncStatement);
mStatement->mAsyncStatement = nullptr;
}
nsCOMPtr<nsIThread> targetThread(mConnection->threadOpenedOn);
NS_ProxyRelease("AsyncStatementFinalizer::mStatement", targetThread,
mStatement.forget());
return NS_OK;
}
private:
RefPtr<StorageBaseStatementInternal> mStatement;
RefPtr<Connection> mConnection;
};
/**
* Finalize a sqlite3_stmt on the background thread for a statement whose
* destructor was invoked and the statement was non-null.
*/
class LastDitchSqliteStatementFinalizer : public Runnable {
public:
/**
* Event constructor.
*
* @param aConnection
* Used to keep the connection alive. If we failed to do this, it
* is possible that the statement going out of scope invoking us
* might have the last reference to the connection and so trigger
* an attempt to close the connection which is doomed to fail
* (because the asynchronous execution thread must exist which will
* trigger the failure case).
* @param aStatement
* The sqlite3_stmt to finalize. This object takes ownership /
* responsibility for the instance and all other references to it
* should be forgotten.
*/
LastDitchSqliteStatementFinalizer(RefPtr<Connection>& aConnection,
sqlite3_stmt* aStatement)
: Runnable("storage::LastDitchSqliteStatementFinalizer"),
mConnection(aConnection),
mAsyncStatement(aStatement) {
MOZ_ASSERT(aConnection, "You must provide a Connection");
}
NS_IMETHOD Run() override {
(void)::sqlite3_finalize(mAsyncStatement);
mAsyncStatement = nullptr;
nsCOMPtr<nsIThread> target(mConnection->threadOpenedOn);
(void)::NS_ProxyRelease("LastDitchSqliteStatementFinalizer::mConnection",
target, mConnection.forget());
return NS_OK;
}
private:
RefPtr<Connection> mConnection;
sqlite3_stmt* mAsyncStatement;
};
////////////////////////////////////////////////////////////////////////////////
//// StorageBaseStatementInternal
StorageBaseStatementInternal::StorageBaseStatementInternal()
: mNativeConnection(nullptr), mAsyncStatement(nullptr) {}
void StorageBaseStatementInternal::asyncFinalize() {
nsIEventTarget* target = mDBConnection->getAsyncExecutionTarget();
if (target) {
// Attempt to finalize asynchronously
nsCOMPtr<nsIRunnable> event =
new AsyncStatementFinalizer(this, mDBConnection);
// Dispatch. Note that dispatching can fail, typically if
// we have a race condition with asyncClose(). It's ok,
// let asyncClose() win.
(void)target->Dispatch(event, NS_DISPATCH_NORMAL);
}
// If we cannot get the background thread,
// mozStorageConnection::AsyncClose() has already been called and
// the statement either has been or will be cleaned up by
// internalClose().
}
void StorageBaseStatementInternal::destructorAsyncFinalize() {
if (!mAsyncStatement) return;
bool isOwningThread = false;
(void)mDBConnection->threadOpenedOn->IsOnCurrentThread(&isOwningThread);
if (isOwningThread) {
// If we are the owning thread (currently that means we're also the
// main thread), then we can get the async target and just dispatch
// to it.
nsIEventTarget* target = mDBConnection->getAsyncExecutionTarget();
if (target) {
nsCOMPtr<nsIRunnable> event =
new LastDitchSqliteStatementFinalizer(mDBConnection, mAsyncStatement);
(void)target->Dispatch(event, NS_DISPATCH_NORMAL);
}
} else {
// If we're not the owning thread, assume we're the async thread, and
// just run the statement.
nsCOMPtr<nsIRunnable> event =
new LastDitchSqliteStatementFinalizer(mDBConnection, mAsyncStatement);
(void)event->Run();
}
// We might not be able to dispatch to the background thread,
// presumably because it is being shutdown. Since said shutdown will
// finalize the statement, we just need to clean-up around here.
mAsyncStatement = nullptr;
}
NS_IMETHODIMP
StorageBaseStatementInternal::NewBindingParamsArray(
mozIStorageBindingParamsArray** _array) {
nsCOMPtr<mozIStorageBindingParamsArray> array = new BindingParamsArray(this);
NS_ENSURE_TRUE(array, NS_ERROR_OUT_OF_MEMORY);
array.forget(_array);
return NS_OK;
}
NS_IMETHODIMP
StorageBaseStatementInternal::ExecuteAsync(
mozIStorageStatementCallback* aCallback,
mozIStoragePendingStatement** _stmt) {
// We used to call Connection::ExecuteAsync but it takes a
// mozIStorageBaseStatement signature because it is also a public API. Since
// our 'this' has no static concept of mozIStorageBaseStatement and Connection
// would just QI it back across to a StorageBaseStatementInternal and the
// actual logic is very simple, we now roll our own.
nsTArray<StatementData> stmts(1);
StatementData data;
nsresult rv = getAsynchronousStatementData(data);
NS_ENSURE_SUCCESS(rv, rv);
stmts.AppendElement(data);
// Dispatch to the background
return AsyncExecuteStatements::execute(std::move(stmts), mDBConnection,
mNativeConnection, aCallback, _stmt);
}
template <typename T>
void EscapeStringForLIKEInternal(const T& aValue,
const typename T::char_type aEscapeChar,
T& aResult) {
const typename T::char_type MATCH_ALL('%');
const typename T::char_type MATCH_ONE('_');
aResult.Truncate(0);
for (uint32_t i = 0; i < aValue.Length(); i++) {
if (aValue[i] == aEscapeChar || aValue[i] == MATCH_ALL ||
aValue[i] == MATCH_ONE) {
aResult += aEscapeChar;
}
aResult += aValue[i];
}
}
NS_IMETHODIMP
StorageBaseStatementInternal::EscapeStringForLIKE(const nsAString& aValue,
const char16_t aEscapeChar,
nsAString& _escapedString) {
EscapeStringForLIKEInternal(aValue, aEscapeChar, _escapedString);
return NS_OK;
}
NS_IMETHODIMP
StorageBaseStatementInternal::EscapeUTF8StringForLIKE(
const nsACString& aValue, const char aEscapeChar,
nsACString& _escapedString) {
EscapeStringForLIKEInternal(aValue, aEscapeChar, _escapedString);
return NS_OK;
}
} // namespace storage
} // namespace mozilla