Introduce codemodelbackend process and library

This is a partial result of wip/clang-oop. More will follow.

This allows us to invoke the completion out of the Qt Creator process
and thus safes us as against libclang crashes.

At this point only the completion use case is supported.

Some notes on the individual components:

 src/libs/codemodelbackendipc
  * library encapsulating the inter process communication handling
  * used by the backend application and in a follow-up change by the
    creator integration

 src/libs/3rdparty/sqlite
  * version 3.8.10.2
  * dependency of codemodelbackendipc, will be used to storage indexing
    data, among others

 src/tools/codemodelbackend
  * the backend application

 tests/unit:
  * unit tests

Change-Id: I91a48e27467581a22fb760a18d8eb926008fea60
Reviewed-by: Alessandro Portale <alessandro.portale@theqtcompany.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>
Reviewed-by: Marco Bubke <marco.bubke@theqtcompany.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>

src/libs/sqlite/sqlitestatement.h

@@ -0,0 +1,138 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://www.qt.io/licensing.  For further information
+** use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file.  Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#ifndef SQLITESTATEMENT_H
+#define SQLITESTATEMENT_H
+
+#include <type_traits>
+#include <memory>
+
+#include <QString>
+#include <QVariant>
+#include <QVector>
+
+#include "sqliteglobal.h"
+
+struct sqlite3_stmt;
+struct sqlite3;
+
+#include "sqliteexception.h"
+#include "utf8stringvector.h"
+
+
+
+class SQLITE_EXPORT SqliteStatement
+{
+protected:
+    explicit SqliteStatement(const Utf8String &sqlStatementUtf8);
+
+    static void deleteCompiledStatement(sqlite3_stmt *compiledStatement);
+
+    bool next() const;
+    void step() const;
+    void reset() const;
+
+    template<typename Type>
+    Type value(int column) const;
+    int columnCount() const;
+    Utf8StringVector columnNames() const;
+
+    void bind(int index, int value);
+    void bind(int index, qint64 value);
+    void bind(int index, double value);
+    void bind(int index, const QString &text);
+    void bind(int index, const QByteArray &blob);
+    void bind(int index, const QVariant &value);
+
+    template <typename Type>
+    void bind(const Utf8String &name, const Type &value);
+
+    int bindingIndexForName(const Utf8String &name);
+
+    void bind(const RowDictionary &rowDictionary);
+    void bindUnchecked(const RowDictionary &rowDictionary);
+
+    void setBindingColumnNames(const Utf8StringVector &bindingColumnNames);
+    const Utf8StringVector &bindingColumnNames() const;
+
+    template <typename ContainerType>
+    ContainerType values(const QVector<int> &columns, int size = 0) const;
+
+    template <typename ContainerType>
+    ContainerType values(int column = 0) const;
+
+    QMap<QString, QVariant> rowColumnValueMap() const;
+    QMap<QString, QVariant> twoColumnValueMap() const;
+
+    static void execute(const Utf8String &sqlStatementUtf8);
+
+    template <typename Type>
+    static Type toValue(const Utf8String &sqlStatementUtf8);
+
+    void prepare(const Utf8String &sqlStatementUtf8);
+    void waitForUnlockNotify() const;
+
+    void write(const RowDictionary &rowDictionary);
+    void writeUnchecked(const RowDictionary &rowDictionary);
+
+    static sqlite3 *sqliteDatabaseHandle();
+    static TextEncoding databaseTextEncoding();
+
+
+    bool checkForStepError(int resultCode) const;
+    void checkForPrepareError(int resultCode) const;
+    void setIfIsReadyToFetchValues(int resultCode) const;
+    void checkIfIsReadyToFetchValues() const;
+    void checkColumnsAreValid(const QVector<int> &columns) const;
+    void checkColumnIsValid(int column) const;
+    void checkBindingIndex(int index) const;
+    void checkBindingName(int index) const;
+    void checkParameterCanBeBound(const RowDictionary &rowDictionary, const Utf8String &columnName);
+    void setBindingParameterCount();
+    void setBindingColumnNamesFromStatement();
+    void setColumnCount();
+    void checkBindingValueMapIsEmpty(const RowDictionary &rowDictionary) const;
+    bool isReadOnlyStatement() const;
+    Q_NORETURN static void throwException(const char *whatHasHappened);
+
+    template <typename ContainerType>
+    ContainerType columnValues(const QVector<int> &columnIndices) const;
+
+    QString columnName(int column) const;
+
+private:
+    std::unique_ptr<sqlite3_stmt, void (*)(sqlite3_stmt*)> compiledStatement;
+    Utf8StringVector  bindingColumnNames_;
+    int bindingParameterCount;
+    int columnCount_;
+    mutable bool isReadyToFetchValues;
+};
+
+#endif // SQLITESTATEMENT_H