Clang: Support second translation unit

A TranslationUnit is owned by TranslationUnits now. TranslationUnits
allows to add another TranslationUnit and to update/query the recently
and previously parsed translation unit.

This does not change any behavior yet.

Change-Id: I8a2f0cc05d3e51bf739dd5d7c4da14b54147f3ab
Reviewed-by: David Schulz <david.schulz@qt.io>

src/tools/clangbackend/ipcsource/clangtranslationunits.cpp

@@ -0,0 +1,135 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#include "clangtranslationunits.h"
+
+#include "clangexceptions.h"
+#include "clangtranslationunit.h"
+
+#include <utils/algorithm.h>
+#include <utils/qtcassert.h>
+
+#include <QFileInfo>
+#include <QLoggingCategory>
+#include <QUuid>
+
+#include <algorithm>
+
+Q_LOGGING_CATEGORY(tuLog, "qtc.clangbackend.translationunits");
+
+namespace ClangBackEnd {
+
+TranslationUnits::TranslationUnits(const Utf8String &filePath)
+    : m_filePath(filePath)
+{
+}
+
+TranslationUnits::~TranslationUnits()
+{
+    foreach (const TranslationUnitData &unit, m_tuDatas) {
+        clang_disposeTranslationUnit(unit.cxTranslationUnit);
+        clang_disposeIndex(unit.cxIndex);
+    }
+}
+
+TranslationUnit TranslationUnits::createAndAppend()
+{
+    const Utf8String id = Utf8String::fromByteArray(QUuid::createUuid().toByteArray());
+    qCDebug(tuLog) << "Creating TranslationUnit" << id << "for" << QFileInfo(m_filePath).fileName();
+
+    m_tuDatas.append(TranslationUnitData(id));
+    TranslationUnitData &translationUnitData = m_tuDatas.last();
+
+    return toTranslationUnit(translationUnitData);
+}
+
+TranslationUnit TranslationUnits::get(PreferredTranslationUnit type)
+{
+    if (m_tuDatas.isEmpty())
+        throw TranslationUnitDoesNotExist(m_filePath);
+
+    if (m_tuDatas.size() == 1 || !areAllTranslationUnitsParsed())
+        return toTranslationUnit(m_tuDatas.first());
+
+    return getPreferredTranslationUnit(type);
+}
+
+void TranslationUnits::updateParseTimePoint(const Utf8String &translationUnitId,
+                                            time_point timePoint)
+{
+    TranslationUnitData &unit = findUnit(translationUnitId);
+
+    QTC_CHECK(timePoint != time_point());
+    unit.parseTimePoint = timePoint;
+
+    qCDebug(tuLog) << "Updated" << translationUnitId << "for" << QFileInfo(m_filePath).fileName()
+        << "RecentlyParsed:" << get(PreferredTranslationUnit::RecentlyParsed).id()
+        << "PreviouslyParsed:" << get(PreferredTranslationUnit::PreviouslyParsed).id();
+}
+
+bool TranslationUnits::areAllTranslationUnitsParsed() const
+{
+    return Utils::allOf(m_tuDatas, [](const TranslationUnitData &unit) {
+        return unit.parseTimePoint != time_point();
+    });
+}
+
+TranslationUnit TranslationUnits::getPreferredTranslationUnit(PreferredTranslationUnit type)
+{
+    using TuData = TranslationUnitData;
+
+    const auto lessThan = [](const TuData &a, const TuData &b) {
+        return a.parseTimePoint < b.parseTimePoint;
+    };
+    auto translationUnitData = type == PreferredTranslationUnit::RecentlyParsed
+            ? std::max_element(m_tuDatas.begin(), m_tuDatas.end(), lessThan)
+            : std::min_element(m_tuDatas.begin(), m_tuDatas.end(), lessThan);
+
+    if (translationUnitData == m_tuDatas.end())
+        throw TranslationUnitDoesNotExist(m_filePath);
+
+    return toTranslationUnit(*translationUnitData);
+}
+
+TranslationUnits::TranslationUnitData &TranslationUnits::findUnit(
+        const Utf8String &translationUnitId)
+{
+    for (TranslationUnitData &unit : m_tuDatas) {
+        if (translationUnitId == unit.id)
+            return unit;
+    }
+
+    throw TranslationUnitDoesNotExist(m_filePath);
+}
+
+TranslationUnit TranslationUnits::toTranslationUnit(TranslationUnits::TranslationUnitData &unit)
+{
+    return TranslationUnit(unit.id,
+                           m_filePath,
+                           unit.cxIndex,
+                           unit.cxTranslationUnit);
+}
+
+} // namespace ClangBackEnd