Fixes: NB#191847 - First application launched with m-booster after theme change crashes

RevBy: Jussi Lind

Details: m and w boosters are killed and restarted when language or
theme changes

src/launcher/CMakeLists.txt

@@ -4,17 +4,19 @@ include(${QT_USE_FILE})
 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_HOME_DIRECTORY}/src/common)
 
 # Set sources
-set(SRC appdata.cpp booster.cpp boosterfactory.cpp connection.cpp daemon.cpp mbooster.cpp logger.cpp main.cpp qtbooster.cpp wrtbooster.cpp)
+set(SRC appdata.cpp booster.cpp boosterfactory.cpp boosterkiller.cpp connection.cpp daemon.cpp mbooster.cpp logger.cpp main.cpp qtbooster.cpp wrtbooster.cpp)
+set(MOC_HDRS boosterkiller.h)
+qt4_wrap_cpp(MOC_SRC ${MOC_HDRS})
 
 # Find libdl
 find_library(LIBDL NAMES dl)
 
 # Set libraries to be linked. Shared libraries to be preloaded are not linked in anymore,
 # but dlopen():ed and listed in src/launcher/preload.h instead. 
-link_libraries(${MEEGOTOUCH_LIBRARIES} ${LIBDL})
+link_libraries(${MEEGOTOUCH_LIBRARIES} ${LIBDL} ${QT_QTCORE_LIBRARY})
 
 # Set executable
-add_executable(applauncherd.bin ${SRC})
+add_executable(applauncherd.bin ${SRC} ${MOC_SRC})
 
 # Add install rule
 install(PROGRAMS applauncherd.bin scripts/applauncherd DESTINATION /usr/bin/)

src/launcher/boosterkiller.cpp

@@ -0,0 +1,33 @@
+#include <QString>
+#include <QCoreApplication>
+#include <QObject>
+#include <MGConfItem>
+#include "boosterkiller.h"
+
+#include <cstdlib>
+
+void BoosterKiller::addKey(const QString & key)
+{
+    MGConfItem *item = new MGConfItem(key, 0);
+    QObject::connect(item, SIGNAL(valueChanged()),
+                     this, SLOT(killProcesses()));
+}
+
+void BoosterKiller::addProcessName(const QString & processName)
+{
+    processNames << processName;
+}
+
+void BoosterKiller::start()
+{
+    int argc = 0;
+    //char **argv = 0;
+    QCoreApplication(argc, 0).exec();
+}
+
+void BoosterKiller::killProcesses()
+{
+    Q_FOREACH(QString processName, processNames) {
+        system( (QString("pkill ") + processName).toStdString().c_str() );
+    }
+}

src/launcher/boosterkiller.h

@@ -0,0 +1,35 @@
+#ifndef BOOSTERKILLER_H
+#define BOOSTERKILLER_H
+
+#include <QObject>
+#include <QStringList>
+
+class QString;
+class MGConfItem;
+
+class BoosterKiller: public QObject
+{
+    Q_OBJECT
+
+ public:
+    /* Add a GConf key and the name of the process that should be
+       killed in case the value associated to the key is changed.
+    */
+    void addKey(const QString & key);
+    void addProcessName(const QString & processName);
+
+    /* Starts the killer. This will initialize qcoreapplication, does
+       not return.
+     */
+    void start();
+
+ private slots:
+    void killProcesses();
+    
+ private:
+    QList<MGConfItem*> gconfItems;
+    QStringList processNames;
+    
+};
+
+#endif

src/launcher/daemon.cpp

@@ -25,6 +25,7 @@
 #include "qtbooster.h"
 #include "wrtbooster.h"
 #include "boosterfactory.h"
+#include "boosterkiller.h"
 #include "preload.h"
 
 
@@ -154,6 +155,8 @@ void Daemon::run()
     // load and resolve all undefined symbols for each dynamic library from the list 
     preload();
 
+    forkKiller();
+
     // Create sockets for each of the boosters
     Connection::initSocket(MBooster::socketName());
     Connection::initSocket(QtBooster::socketName());
@@ -206,6 +209,22 @@ void Daemon::run()
     }
 }
 
+bool Daemon::forkKiller()
+{
+    pid_t pid = fork();
+    if (pid == -1)
+        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Forking killer process failed.");
+    if (pid == 0) { // child
+        // If theme or language changes, reset boosters
+        BoosterKiller bk;
+        bk.addKey("/meegotouch/theme/name");
+        bk.addKey("/meegotouch/i18n/language");
+        bk.addProcessName("booster-m");
+        bk.addProcessName("booster-w");
+        bk.start(); // does not return.
+    }
+}
+
 bool Daemon::forkBooster(char type, int sleepTime)
 {
     // Fork a new process

src/launcher/daemon.h

@@ -95,6 +95,9 @@ private:
     //! Fork to a daemon
     void daemonize();
 
+    //! Fork process that kills boosters if needed
+    bool forkKiller();
+
     //! Forks and initializes a new Booster
     bool forkBooster(char type, int sleepTime = 0);