Implement new plugin mechanism

moc can now embed meta information about the plugin
inside the plugin itself. This information can
be queried by Qt without having to load the plugin.

Source compatibility with the old plugin loading
mechanism is still there, but will be removed before
Qt 5.0.

Change-Id: I03e4196ddfed07d0fe94acca40d5de8a6ce7f920
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/src/tools/moc/generator.cpp b/src/tools/moc/generator.cpp
index b4f3d23f4e..e2055e44e8 100644
--- a/src/tools/moc/generator.cpp
+++ b/src/tools/moc/generator.cpp
@@ -43,6 +43,11 @@
 #include "outputrevision.h"
 #include "utils.h"
 #include <QtCore/qmetatype.h>
+#include <QtCore/qjsondocument.h>
+#include <QtCore/qjsonobject.h>
+#include <QtCore/qjsonvalue.h>
+#include <QtCore/qjsonarray.h>
+#include <QtCore/qplugin.h>
 #include <stdio.h>
 
 #include <private/qmetaobject_p.h> //for the flags.
@@ -421,6 +426,11 @@ void Generator::generateCode()
 //
     for (int signalindex = 0; signalindex < cdef->signalList.size(); ++signalindex)
         generateSignal(&cdef->signalList[signalindex], signalindex);
+
+//
+// Generate plugin meta data
+//
+    generatePluginMetaData();
 }
 
 
@@ -1051,4 +1061,42 @@ void Generator::generateSignal(FunctionDef *def,int index)
     fprintf(out, "}\n");
 }
 
+void Generator::generatePluginMetaData()
+{
+    if (cdef->pluginData.iid.isEmpty())
+        return;
+
+    QJsonObject data;
+    data.insert(QLatin1String("IID"), QLatin1String(cdef->pluginData.iid.constData()));
+    data.insert(QLatin1String("className"), QLatin1String(cdef->classname.constData()));
+    data.insert(QLatin1String("version"), (int)QT_VERSION);
+    data.insert(QLatin1String("debug"),
+#ifdef QT_NO_DEBUG
+                false
+#else
+                true
+#endif
+                );
+    data.insert(QLatin1String("MetaData"), cdef->pluginData.metaData.object());
+    QJsonDocument doc(data);
+
+    fprintf(out, "\nQT_PLUGIN_METADATA_SECTION const uint qt_section_alignment_dummy = 42;\n");
+    fprintf(out,
+            "\nQT_PLUGIN_METADATA_SECTION\n"
+            "static const unsigned char qt_pluginMetaData[] = {\n"
+            "    'Q', 'T', 'M', 'E', 'T', 'A', 'D', 'A', 'T', 'A', ' ', ' ',\n   ");
+#if 0
+    fprintf(out, "\"%s\";\n", doc.toJson().constData());
+#else
+    QByteArray binary = doc.toBinaryData();
+    for (int i = 0; i < binary.size() - 1; ++i) {
+        fprintf(out, " 0x%02x,", (uchar)binary.at(i));
+        if (!((i + 1) % 8))
+            fprintf(out, "\n   ");
+    }
+    fprintf(out, " 0x%02x\n};\n", (uchar)binary.at(binary.size() - 1));
+#endif
+    fprintf(out, "QT_MOC_EXPORT_PLUGIN(%s)\n\n", cdef->classname.constData());
+}
+
 QT_END_NAMESPACE