From 570e7b38487455d394b5b74a59edc639f3dc416f Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Thu, 13 Jan 2011 15:52:17 +0200
Subject: Fix QSystemSemaphore handle management issues in Symbian

QSystemSemaphore native RSemaphore handle was unnecessarily created
again on each acquire. The creation logic was also susceptible for
random failures when two or more threads tried simultaneously acquire
the semaphore.

Task-number: QTBUG-16615
Reviewed-by: Janne Koskinen
---
 src/corelib/kernel/qsystemsemaphore_symbian.cpp | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/src/corelib/kernel/qsystemsemaphore_symbian.cpp b/src/corelib/kernel/qsystemsemaphore_symbian.cpp
index a25a119..07cfffc 100644
--- a/src/corelib/kernel/qsystemsemaphore_symbian.cpp
+++ b/src/corelib/kernel/qsystemsemaphore_symbian.cpp
@@ -73,6 +73,9 @@ void QSystemSemaphorePrivate::setErrorString(const QString &function, int err)
     case KErrInUse:
         errorString = QCoreApplication::tr("%1: out of resources", "QSystemSemaphore").arg(function);
         error = QSystemSemaphore::OutOfResources;
+    case KErrPermissionDenied:
+        errorString = QCoreApplication::tr("%1: permission denied", "QSystemSemaphore").arg(function);
+        error = QSystemSemaphore::PermissionDenied;
     break;
 default:
     errorString = QCoreApplication::tr("%1: unknown error %2", "QSystemSemaphore").arg(function).arg(err);
@@ -86,15 +89,24 @@ default:
 
 int QSystemSemaphorePrivate::handle(QSystemSemaphore::AccessMode)
 {
+    if (semaphore.Handle()) {
+        return semaphore.Handle();
+    }
+
     // don't allow making handles on empty keys
     if (key.isEmpty())
         return 0;
+
     QString safeName = makeKeyFileName();
     TPtrC name(qt_QString2TPtrC(safeName));
-    int err;
-    err = semaphore.OpenGlobal(name,EOwnerProcess);
-    if (err == KErrNotFound){
-        err = semaphore.CreateGlobal(name,initialValue, EOwnerProcess);
+    int err = KErrAlreadyExists;
+    int tryCount = 10;
+    // Sort out race conditions by retrying several times until existing handle is acquired.
+    // Sometimes opening can fail inexplicably with KErrPermissionDenied many times in a row.
+    while (err != KErrNoMemory && err != KErrNone && tryCount-- >= 0) {
+        err = semaphore.CreateGlobal(name, initialValue, EOwnerProcess);
+        if (err != KErrNoMemory && err != KErrNone)
+            err = semaphore.OpenGlobal(name,EOwnerProcess);
     }
     if (err){
         setErrorString(QLatin1String("QSystemSemaphore::handle"),err);
-- 
cgit v0.12


From c67b4cda2f5a7afd401ec3106e3a7b018fd9881d Mon Sep 17 00:00:00 2001
From: Miikka Heikkinen <miikka.heikkinen@digia.com>
Date: Thu, 13 Jan 2011 16:08:42 +0200
Subject: Fix QSharedMemory and QSystemSemaphore autotests for Symbian

Reviewed-by: Janne Koskinen
---
 tests/auto/qtipc/qsharedmemory/tst_qsharedmemory.cpp   | 10 +++++-----
 tests/auto/qtipc/qsystemsemaphore/qsystemsemaphore.pro |  5 ++++-
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/tests/auto/qtipc/qsharedmemory/tst_qsharedmemory.cpp b/tests/auto/qtipc/qsharedmemory/tst_qsharedmemory.cpp
index 5825524..50205bc 100644
--- a/tests/auto/qtipc/qsharedmemory/tst_qsharedmemory.cpp
+++ b/tests/auto/qtipc/qsharedmemory/tst_qsharedmemory.cpp
@@ -51,7 +51,7 @@
 #define EXISTING_SIZE 1024
 
 #ifdef Q_OS_SYMBIAN
-#define SRCDIR "c:/data/qsharedmemorytemp/"
+#define SRCDIR "c:/data/qsharedmemorytemp/lackey/"
 #define LACKEYDIR SRCDIR "lackey"
 #elif defined(Q_OS_WINCE)
 #define LACKEYDIR SRCDIR
@@ -624,6 +624,10 @@ public:
         QVERIFY(producer.isAttached());
         char *memory = (char*)producer.data();
         memory[1] = '0';
+#if defined(Q_OS_SYMBIAN)
+        // Sleep a while to ensure that consumers start properly
+        QTest::qSleep(1000);
+#endif
         QTime timer;
         timer.start();
         int i = 0;
@@ -645,10 +649,6 @@ public:
         memory[0] = 'E';
         QVERIFY(producer.unlock());
 
-#if defined(Q_OS_SYMBIAN)
-        // Sleep a while to ensure that consumers start properly
-        QTest::qSleep(1000);
-#endif
     }
 private:
 
diff --git a/tests/auto/qtipc/qsystemsemaphore/qsystemsemaphore.pro b/tests/auto/qtipc/qsystemsemaphore/qsystemsemaphore.pro
index 8a5f8b2..e21e5df 100644
--- a/tests/auto/qtipc/qsystemsemaphore/qsystemsemaphore.pro
+++ b/tests/auto/qtipc/qsystemsemaphore/qsystemsemaphore.pro
@@ -1,4 +1,4 @@
-CONFIG += qttest_p4
+load(qttest_p4)
 #QT = core
 
 include(../qsharedmemory/src/src.pri)
@@ -31,5 +31,8 @@ QT += script
 lackey.sources = ../lackey/lackey.exe
 lackey.path = /sys/bin
 DEPLOYMENT += lackey
+
+# PowerMgmt capability needed to kill lackey process
+TARGET.CAPABILITY = PowerMgmt
 }
 
-- 
cgit v0.12