New QmlDesigner plugin & Design mode

This adds a new "Design" mode that can be used to manipulate qml files
in a visual way. It will only get build if you have the declarativeui
module in Qt.

This is a squashed import from the Bauhaus project. Share & enjoy :)

src/plugins/qmldesigner/components/pluginmanager/pluginpath.cpp

@@ -0,0 +1,193 @@
+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#include "pluginpath.h"
+#include <iplugin.h>
+#include <QtCore/QLibrary>
+#include <QWeakPointer>
+#include <QtCore/QPluginLoader>
+#include <QtCore/QFileInfo>
+#include <QtCore/QLibraryInfo>
+#include <QtCore/QCoreApplication>
+#include <QtCore/QObject>
+#include <QtCore/QSharedData>
+#include <QDebug>
+
+enum { debug = 1 };
+
+namespace QmlDesigner {
+
+// Initialize and create instance of a plugin from scratch,
+// that is, make sure the library is loaded and has an instance
+// of the IPlugin type. Once something fails, mark it as failed
+// ignore it from then on.
+static IPlugin *instance(PluginData &p)
+{
+    // Go stale once something fails
+    if (p.failed)
+        return 0;
+    // Pull up the plugin, retrieve IPlugin instance.
+    if (!p.instanceGuard) {
+        p.instance = 0;
+        QPluginLoader loader(p.path);
+        if (!(loader.isLoaded() || loader.load())) {
+            p.failed = true;
+            p.errorMessage = loader.errorString();
+            return 0;
+        }
+        QObject *object = loader.instance();
+        if (!object) {
+            p.failed = true;
+            p.errorMessage = QCoreApplication::translate("WidgetPluginManager", "Failed to create instance.");
+            return 0;
+        }
+        IPlugin *iplugin = qobject_cast<IPlugin *>(object);
+        if (!iplugin) {
+            p.failed = true;
+            p.errorMessage = QCoreApplication::translate("WidgetPluginManager", "Not a QmlDesigner plugin.");
+            delete object;
+            return 0;
+        }
+        p.instanceGuard = object;
+        p.instance = iplugin;
+    }
+    // Ensure it is initialized
+    /*if (!p.instance->isInitialized()) {
+        if (!p.instance->initialize(&p.errorMessage)) {
+            p.failed = true;
+            delete p.instance;
+            p.instance = 0;
+            return 0;
+        }
+    }*/
+    return p.instance;
+}
+
+PluginData::PluginData(const QString &p) :
+    path(p),
+    failed(false),
+    instance(0)
+{
+}
+
+
+PluginPath::PluginPath(const QDir &path) :
+    m_path(path),
+    m_loaded(false)
+{
+}
+
+// Determine a unique list of library files in that directory
+QStringList PluginPath::libraryFilePaths(const QDir &dir)
+{
+    const QFileInfoList infoList = dir.entryInfoList(QDir::Files|QDir::Readable|QDir::NoDotAndDotDot);
+    if (infoList.empty())
+        return QStringList();
+      // Load symbolic links but make sure all file names are unique as not
+    // to fall for something like 'libplugin.so.1 -> libplugin.so'
+    QStringList result;
+    const QFileInfoList::const_iterator icend = infoList.constEnd();
+    for (QFileInfoList::const_iterator it = infoList.constBegin(); it != icend; ++it) {
+        QString fileName;
+        if (it->isSymLink()) {
+            const QFileInfo linkTarget = QFileInfo(it->symLinkTarget());
+            if (linkTarget.exists() && linkTarget.isFile())
+                fileName = linkTarget.absoluteFilePath();
+        } else {
+            fileName = it->absoluteFilePath();
+        }
+        if (!fileName.isEmpty() && QLibrary::isLibrary(fileName) && !result.contains(fileName))
+            result += fileName;
+    }
+
+	qDebug() << "Library file paths: " << result;
+
+    return result;
+}
+
+void PluginPath::clear()
+{
+    m_loaded = false;
+    m_plugins.clear();
+}
+
+void PluginPath::ensureLoaded()
+{
+    if (!m_loaded) {
+        const QStringList libraryFiles = libraryFilePaths(m_path);
+        if (debug)
+            qDebug() << "Checking " << libraryFiles.size() << " plugins " << m_path.absolutePath();
+        foreach (const QString &libFile, libraryFiles)
+            m_plugins.push_back(PluginData(libFile));
+        m_loaded = true;
+    }
+}
+
+void PluginPath::getInstances(PluginManager::IPluginList *list)
+{
+    ensureLoaded();
+    // Compile list of instances
+    if (m_plugins.empty())
+        return;
+    const PluginDataList::iterator end = m_plugins.end();
+    for (PluginDataList::iterator it = m_plugins.begin(); it != end; ++it)
+        if (IPlugin *i = instance(*it))
+            list->push_back(i);
+}
+
+QStandardItem *PluginPath::createModelItem()
+{
+    ensureLoaded();
+    // Create a list of plugin lib files with classes.
+    // If there are failed ones, create a separate "Failed"
+    // category at the end
+    QStandardItem *pathItem = new QStandardItem(m_path.absolutePath());
+    QStandardItem *failedCategory = 0;
+    const PluginDataList::iterator end = m_plugins.end();
+    for (PluginDataList::iterator it = m_plugins.begin(); it != end; ++it) {
+        QStandardItem *pluginItem = new QStandardItem(QFileInfo(it->path).fileName());
+        if (instance(*it)) {
+            pluginItem->appendRow(new QStandardItem(QString::fromLatin1(it->instanceGuard->metaObject()->className())));
+            pathItem->appendRow(pluginItem);
+        } else {
+            pluginItem->setToolTip(it->errorMessage);
+            if (!failedCategory) {
+                const QString failed = QCoreApplication::translate("PluginManager", "Failed Plugins");
+                failedCategory = new QStandardItem(failed);
+            }
+            failedCategory->appendRow(pluginItem);
+        }
+    }
+    if (failedCategory)
+        pathItem->appendRow(failedCategory);
+    return pathItem;
+}
+
+} // namespace QmlDesigner
+