kde-apps/akonadi/files/akonadi-18.12.3-akonadi_control-start-race-condition.patch

   1 From c21bb5220a3ae835a5183afd58c186ba21f6c93d Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Daniel=20Vr=C3=A1til?= <dvratil@kde.org>
   3 Date: Fri, 28 Jun 2019 17:10:04 +0200
   4 Subject: Fix race-condition on akonadi_control start
   5
   6 Summary:
   7 Check that there are no other akonadi_control instances running as the
   8 very first thing on startup. Previously this check would happen after
   9 AkApplication initialization, which contains some potential race-
  10 conditions, like rotating log files.
  11
  12 The situation when akonadi_control is launched multiple times can occur
  13 on session startup, when multiple different components will attempt to
  14 launch Akonadi if its not yet running.
  15
  16 BUG: 392092
  17 FIXED-IN: 19.04.3
  18
  19 Reviewers: #kde_pim, vkrause
  20
  21 Reviewed By: #kde_pim, vkrause
  22
  23 Subscribers: kde-pim
  24
  25 Tags: #kde_pim
  26
  27 Differential Revision: https://phabricator.kde.org/D22092
  28 ---
  29  src/akonadicontrol/main.cpp  | 16 ++-------------
  30  src/shared/akapplication.cpp |  7 +++----
  31  src/shared/akapplication.h   | 49 ++++++++++++++++++++++++++++++++++++++------
  32  3 files changed, 48 insertions(+), 24 deletions(-)
  33
  34 diff --git a/src/akonadicontrol/main.cpp b/src/akonadicontrol/main.cpp
  35 index 19bebb8..7dba85b 100644
  36 --- a/src/akonadicontrol/main.cpp
  37 +++ b/src/akonadicontrol/main.cpp
  38 @@ -52,7 +52,7 @@ void crashHandler(int)
  39
  40  int main(int argc, char **argv)
  41  {
  42 -    AkGuiApplication app(argc, argv, AKONADICONTROL_LOG());
  43 +    AkUniqueGuiApplication app(argc, argv, Akonadi::DBus::serviceName(Akonadi::DBus::ControlLock), AKONADICONTROL_LOG());
  44      app.setDescription(QStringLiteral("Akonadi Control Process\nDo not run this manually, use 'akonadictl' instead to start/stop Akonadi."));
  45
  46      KAboutData aboutData(QStringLiteral("akonadi_control"),
  47 @@ -64,20 +64,8 @@ int main(int argc, char **argv)
  48
  49      app.parseCommandLine();
  50
  51 -    // try to acquire the lock first, that means there is no second instance trying to start up at the same time
  52 -    // registering the real service name happens in AgentManager::continueStartup(), when everything is in fact up and running
  53 -    if (!QDBusConnection::sessionBus().registerService(Akonadi::DBus::serviceName(Akonadi::DBus::ControlLock))) {
  54 -        // We couldn't register. Most likely, it's already running.
  55 -        const QString lastError = QDBusConnection::sessionBus().lastError().message();
  56 -        if (lastError.isEmpty()) {
  57 -            qCWarning(AKONADICONTROL_LOG) << "Unable to register service as" << Akonadi::DBus::serviceName(Akonadi::DBus::ControlLock) << "Maybe it's already running?";
  58 -        } else {
  59 -            qCWarning(AKONADICONTROL_LOG) << "Unable to register service as" << Akonadi::DBus::serviceName(Akonadi::DBus::ControlLock) << "Error was:" << lastError;
  60 -        }
  61 -        return -1;
  62 -    }
  63 -
  64      // older Akonadi server versions don't use the lock service yet, so check if one is already running before we try to start another one
  65 +    // TODO: Remove this legacy check?
  66      if (QDBusConnection::sessionBus().interface()->isServiceRegistered(Akonadi::DBus::serviceName(Akonadi::DBus::Control))) {
  67          qCWarning(AKONADICONTROL_LOG) << "Another Akonadi control process is already running.";
  68          return -1;
  69 diff --git a/src/shared/akapplication.cpp b/src/shared/akapplication.cpp
  70 index af860e5..b790b8d 100644
  71 --- a/src/shared/akapplication.cpp
  72 +++ b/src/shared/akapplication.cpp
  73 @@ -32,10 +32,9 @@
  74
  75  AkApplicationBase *AkApplicationBase::sInstance = nullptr;
  76
  77 -AkApplicationBase::AkApplicationBase(int &argc, char **argv, const QLoggingCategory &loggingCategory)
  78 +AkApplicationBase::AkApplicationBase(std::unique_ptr<QCoreApplication> app, const QLoggingCategory &loggingCategory)
  79      : QObject(nullptr)
  80 -    , mArgc(argc)
  81 -    , mArgv(argv)
  82 +    , mApp(std::move(app))
  83      , mLoggingCategory(loggingCategory)
  84  {
  85      Q_ASSERT(!sInstance);
  86 @@ -59,7 +58,7 @@ AkApplicationBase *AkApplicationBase::instance()
  87
  88  void AkApplicationBase::init()
  89  {
  90 -    akInit(QString::fromLatin1(mArgv[0]));
  91 +    akInit(mApp->applicationName());
  92      akInitRemoteLog();
  93
  94      if (!QDBusConnection::sessionBus().isConnected()) {
  95 diff --git a/src/shared/akapplication.h b/src/shared/akapplication.h
  96 index aae7a99..433b725 100644
  97 --- a/src/shared/akapplication.h
  98 +++ b/src/shared/akapplication.h
  99 @@ -23,6 +23,10 @@
 100  #include <QObject>
 101  #include <QCommandLineParser>
 102  #include <QLoggingCategory>
 103 +#include <QDBusConnection>
 104 +#include <QDBusError>
 105 +
 106 +#include <memory>
 107
 108  class QCoreApplication;
 109  class QApplication;
 110 @@ -55,16 +59,15 @@ public:
 111      int exec();
 112
 113  protected:
 114 -    AkApplicationBase(int &argc, char **argv, const QLoggingCategory &loggingCategory);
 115 +    AkApplicationBase(std::unique_ptr<QCoreApplication> app, const QLoggingCategory &loggingCategory);
 116      void init();
 117 -    QScopedPointer<QCoreApplication> mApp;
 118 +
 119 +    std::unique_ptr<QCoreApplication> mApp;
 120
 121  private Q_SLOTS:
 122      void pollSessionBus() const;
 123
 124  private:
 125 -    int mArgc;
 126 -    char **mArgv;
 127      QString mInstanceId;
 128      const QLoggingCategory &mLoggingCategory;
 129      static AkApplicationBase *sInstance;
 130 @@ -77,13 +80,46 @@ class AkApplicationImpl : public AkApplicationBase
 131  {
 132  public:
 133      AkApplicationImpl(int &argc, char **argv, const QLoggingCategory &loggingCategory = *QLoggingCategory::defaultCategory())
 134 -        : AkApplicationBase(argc, argv, loggingCategory)
 135 +        : AkApplicationBase(std::make_unique<T>(argc, argv), loggingCategory)
 136      {
 137 -        mApp.reset(new T(argc, argv));
 138          init();
 139      }
 140  };
 141
 142 +template<typename T>
 143 +class AkUniqueApplicationImpl : public AkApplicationBase
 144 +{
 145 +public:
 146 +    AkUniqueApplicationImpl(int &argc, char **argv, const QString &serviceName, const QLoggingCategory &loggingCategory = *QLoggingCategory::defaultCategory())
 147 +        : AkApplicationBase(std::make_unique<T>(argc, argv), loggingCategory)
 148 +    {
 149 +        registerUniqueServiceOrTerminate(serviceName, loggingCategory);
 150 +        init();
 151 +    }
 152 +
 153 +private:
 154 +    void registerUniqueServiceOrTerminate(const QString &serviceName, const QLoggingCategory &log)
 155 +    {
 156 +        auto bus = QDBusConnection::sessionBus();
 157 +        if (!bus.isConnected()) {
 158 +            qCCritical(log, "Session bus not found. Is DBus running?");
 159 +            exit(1);
 160 +        }
 161 +
 162 +        if (!bus.registerService(serviceName)) {
 163 +            // We couldn't register. Most likely, it's already running.
 164 +            const QString lastError = bus.lastError().message();
 165 +            if (lastError.isEmpty()) {
 166 +                qCInfo(log, "Service %s already registered, terminating now.", qUtf8Printable(serviceName));
 167 +                exit(0); // already running, so it's OK. Terminate now.
 168 +            } else {
 169 +                qCCritical(log, "Unable to register service as %s due to an error: %s", qUtf8Printable(serviceName), qUtf8Printable(lastError));
 170 +                exit(1); // :(
 171 +            }
 172 +        }
 173 +    }
 174 +};
 175 +
 176  /**
 177   * Returns the contents of @p name environment variable if it is defined,
 178   * or @p defaultValue otherwise.
 179 @@ -93,5 +129,6 @@ QString akGetEnv(const char *name, const QString &defaultValue = QString());
 180  typedef AkApplicationImpl<QCoreApplication> AkCoreApplication;
 181  typedef AkApplicationImpl<QApplication> AkApplication;
 182  typedef AkApplicationImpl<QGuiApplication> AkGuiApplication;
 183 +typedef AkUniqueApplicationImpl<QGuiApplication> AkUniqueGuiApplication;
 184
 185  #endif
 186 --
 187 cgit v1.1