From fb3e09c620b519eed57488cb229d42ebb793f387 Mon Sep 17 00:00:00 2001
From: Thiago Macieira <thiago.macieira@nokia.com>
Date: Wed, 7 Oct 2009 11:55:58 +0200
Subject: Use the recursive mutex functions for D-Bus only.

At least in D-Bus 1.2.16, there's a deadlock caused by locking an
already-locked mutex. When Qt is linked to libdbus-1 instead of
dynamically loading it, it maintains legacy compatibility by only
providing the non-recursive mutexes, which triggers this deadlock.

The recursive functions have been present since 0.93, so I guess the
non-recursive variants aren't tested.

Report: https://bugzilla.novell.com/show_bug.cgi?id=482749#c30
---
 configure                |  2 +-
 dist/changes-4.6.0       |  5 ++++-
 src/dbus/qdbusthread.cpp | 32 +++++---------------------------
 3 files changed, 10 insertions(+), 29 deletions(-)

diff --git a/configure b/configure
index ea50b37..1a7a8ef 100755
--- a/configure
+++ b/configure
@@ -617,7 +617,7 @@ fi
 unset QTDIR
 
 # the minimum version of libdbus-1 that we require:
-MIN_DBUS_1_VERSION=0.62
+MIN_DBUS_1_VERSION=0.93
 
 # initalize internal variables
 CFG_CONFIGURE_EXIT_ON_ERROR=yes
diff --git a/dist/changes-4.6.0 b/dist/changes-4.6.0
index 2e7e699..cd9f130 100644
--- a/dist/changes-4.6.0
+++ b/dist/changes-4.6.0
@@ -19,6 +19,9 @@ information about a particular change.
 *                           General                                        *
 ****************************************************************************
 
+ - QtDBus
+   * The minimum required version of the D-Bus reference library is
+     now 0.93.
 
 
 ****************************************************************************
@@ -133,4 +136,4 @@ information about a particular change.
    for all floating point numbers, and this can be changed using the new 
    function setFloatingPointPrecision(). Set Qt_4_5 as the version of the 
    QDataStream to get the behavior of previous versions.
-   
\ No newline at end of file
+   
diff --git a/src/dbus/qdbusthread.cpp b/src/dbus/qdbusthread.cpp
index 6e180b1..7bc107a 100644
--- a/src/dbus/qdbusthread.cpp
+++ b/src/dbus/qdbusthread.cpp
@@ -47,33 +47,24 @@
 
 QT_USE_NAMESPACE
 
-static DBusMutex* mutex_new()
-{
-    return reinterpret_cast<DBusMutex *>(new QMutex(QMutex::NonRecursive));
-}
-
-#if 0
 static DBusMutex* recursive_mutex_new()
 {
     return reinterpret_cast<DBusMutex *>(new QMutex(QMutex::Recursive));
 }
-#endif
 
 static void mutex_free(DBusMutex *mutex)
 {
     delete reinterpret_cast<QMutex *>(mutex);
 }
 
-static dbus_bool_t mutex_lock(DBusMutex *mutex)
+static void mutex_lock(DBusMutex *mutex)
 {
     reinterpret_cast<QMutex *>(mutex)->lock();
-    return true;
 }
 
-static dbus_bool_t mutex_unlock(DBusMutex *mutex)
+static void mutex_unlock(DBusMutex *mutex)
 {
     reinterpret_cast<QMutex *>(mutex)->unlock();
-    return true;
 }
 
 static DBusCondVar* condvar_new()
@@ -110,42 +101,29 @@ QT_BEGIN_NAMESPACE
 
 bool qDBusInitThreads()
 {
-    // ### Disable the recursive mutex functions.
+    // Use only the non-recursive mutex functions
     static DBusThreadFunctions fcn = {
-        DBUS_THREAD_FUNCTIONS_MUTEX_NEW_MASK |
-        DBUS_THREAD_FUNCTIONS_MUTEX_FREE_MASK |
-        DBUS_THREAD_FUNCTIONS_MUTEX_LOCK_MASK |
-        DBUS_THREAD_FUNCTIONS_MUTEX_UNLOCK_MASK |
         DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK |
         DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK |
         DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK |
         DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK |
         DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK |
-        DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK,
-#if 0
+        DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK |
         DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK |
         DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK |
         DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK |
         DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK,
-#endif
-        mutex_new,
-        mutex_free,
-        mutex_lock,
-        mutex_unlock,
+        0, 0, 0, 0, // non-recursive mutex functions
         condvar_new,
         condvar_free,
         condvar_wait,
         condvar_wait_timeout,
         condvar_wake_one,
         condvar_wake_all,
-#if 0
         recursive_mutex_new,
         mutex_free,
         mutex_lock,
         mutex_unlock,
-#else
-        0, 0, 0, 0,
-#endif
         0, 0, 0, 0
     };
 
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