Clang: On the road to update and preprocessor support

This patch has grown in a quite big change set and it is really hard to
divide it in different parts.
V2::ProjectPartContainer is now using FileIds instead of file paths. This
cleans code up because it is a big step in the direction that internally
only file ids are used. But it is depending on the file cache, so the
file cache has to be provided as an argument. There is now an interface for
transactions too which are ease the testing of them and enables the support
of preprocessor. It adds macros as symbols and is saving used macros. The
used macro support is enabling update improvements because only if a
changed macro is used it needs to be recompiled. This is still in flux
and can be changed in later patches.

Change-Id: I492a2c9af1201d40fdd9f46a0045f7878bbbaa3d
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/libs/sqlite/sqlitetransaction.h

@@ -34,65 +34,77 @@ namespace Sqlite {
 class DatabaseBackend;
 class Database;
 
-template <typename Database>
+class TransactionInterface
+{
+public:
+    TransactionInterface() = default;
+    virtual ~TransactionInterface();
+    TransactionInterface(const TransactionInterface &) = delete;
+    TransactionInterface &operator=(const TransactionInterface &) = delete;
+
+    virtual void deferredBegin() = 0;
+    virtual void immediateBegin() = 0;
+    virtual void exclusiveBegin() = 0;
+    virtual void commit() = 0;
+    virtual void rollback() = 0;
+};
+
 class AbstractTransaction
 {
 public:
     ~AbstractTransaction()
     {
         if (!m_isAlreadyCommited)
-            m_database.execute("ROLLBACK");
+            m_interface.rollback();
     }
 
+    AbstractTransaction(const AbstractTransaction &) = delete;
+    AbstractTransaction &operator=(const AbstractTransaction &) = delete;
+
     void commit()
     {
-        m_database.execute("COMMIT");
+        m_interface.commit();
         m_isAlreadyCommited = true;
     }
 
 protected:
-    AbstractTransaction(Database &database)
-        : m_databaseLock(database.databaseMutex()),
-          m_database(database)
+    AbstractTransaction(TransactionInterface &interface)
+        : m_interface(interface)
     {
     }
 
 private:
-    std::lock_guard<typename Database::MutexType> m_databaseLock;
-    Database &m_database;
+    TransactionInterface &m_interface;
     bool m_isAlreadyCommited = false;
 };
 
-template <typename Database>
-class DeferredTransaction final : public AbstractTransaction<Database>
+class DeferredTransaction final : public AbstractTransaction
 {
 public:
-    DeferredTransaction(Database &database)
-        : AbstractTransaction<Database>(database)
+    DeferredTransaction(TransactionInterface &interface)
+        : AbstractTransaction(interface)
     {
-        database.execute("BEGIN");
+        interface.deferredBegin();
     }
 };
 
-template <typename Database>
-class ImmediateTransaction final : public AbstractTransaction<Database>
+class ImmediateTransaction final : public AbstractTransaction
 {
 public:
-    ImmediateTransaction(Database &database)
-        : AbstractTransaction<Database>(database)
+    ImmediateTransaction(TransactionInterface &interface)
+        : AbstractTransaction(interface)
     {
-        database.execute("BEGIN IMMEDIATE");
+        interface.immediateBegin();
     }
 };
 
-template <typename Database>
-class ExclusiveTransaction final : public AbstractTransaction<Database>
+class ExclusiveTransaction final : public AbstractTransaction
 {
 public:
-    ExclusiveTransaction(Database &database)
-        : AbstractTransaction<Database>(database)
+    ExclusiveTransaction(TransactionInterface &interface)
+        : AbstractTransaction(interface)
     {
-        database.execute("BEGIN EXCLUSIVE");
+        interface.exclusiveBegin();
     }
 };