Avoid races when using OSX_RUNINMAIN_MEMBERS

...so that e.g. main thread in SalYieldMutex::doAcquire could reset
m_aInMainTHreadCondition and then block waiting on it only after another thread
had set it.  (Saw such a deadlock in some 'make check' CppunitTest.)

Change-Id: I5c676956a2bec6bf8f94d7dbeee64f100db39bd3
Reviewed-on: https://gerrit.libreoffice.org/44501
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

2 files changed, 54 insertions, 29 deletions

diff --git a/vcl/inc/osx/runinmain.hxx b/vcl/inc/osx/runinmain.hxx
index a57b7908214d..8f8559dac5c8 100644
--- a/vcl/inc/osx/runinmain.hxx
+++ b/vcl/inc/osx/runinmain.hxx
@@ -57,8 +57,11 @@ union RuninmainResult
 };
 
 #define OSX_RUNINMAIN_MEMBERS \
-    osl::Condition          m_aInMainCondition; \
-    osl::Condition          m_aResultCondition; \
+    std::mutex              m_runInMainMutex; \
+    std::condition_variable m_aInMainCondition; \
+    std::condition_variable m_aResultCondition; \
+    bool                    m_wakeUpMain = false; \
+    bool                    m_resultReady = false; \
     RuninmainBlock          m_aCodeBlock; \
     RuninmainResult         m_aResult;
 
@@ -67,18 +70,24 @@ union RuninmainResult
     { \
         DBG_TESTSOLARMUTEX(); \
         SalYieldMutex *aMutex = static_cast<SalYieldMutex*>(instance->GetYieldMutex()); \
-        assert( !aMutex->m_aCodeBlock ); \
-        aMutex->m_aCodeBlock = Block_copy(^{ \
-            command; \
-        }); \
-        aMutex->m_aResultCondition.reset(); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            assert( !aMutex->m_aCodeBlock ); \
+            aMutex->m_aCodeBlock = Block_copy(^{ \
+                command; \
+            }); \
+            aMutex->m_wakeUpMain = true; \
+            aMutex->m_aInMainCondition.notify_all(); \
+        } \
         dispatch_async(dispatch_get_main_queue(),^{ \
             ImplNSAppPostEvent( AquaSalInstance::YieldWakeupEvent, NO ); \
             }); \
-        aMutex->m_aInMainCondition.set(); \
-        osl::Condition::Result res =  aMutex->m_aResultCondition.wait(); \
-        (void) res; \
-        assert(osl::Condition::Result::result_ok == res); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            aMutex->m_aResultCondition.wait( \
+                g, [&aMutex]() { return aMutex->m_resultReady; }); \
+            aMutex->m_resultReady = false; \
+        } \
         return; \
     }
 
@@ -87,18 +96,24 @@ union RuninmainResult
     { \
         DBG_TESTSOLARMUTEX(); \
         SalYieldMutex *aMutex = static_cast<SalYieldMutex*>(instance->GetYieldMutex()); \
-        assert( !aMutex->m_aCodeBlock ); \
-        aMutex->m_aCodeBlock = Block_copy(^{ \
-            aMutex->m_aResult.pointer = static_cast<void*>( command ); \
-        }); \
-        aMutex->m_aResultCondition.reset(); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            assert( !aMutex->m_aCodeBlock ); \
+            aMutex->m_aCodeBlock = Block_copy(^{ \
+                aMutex->m_aResult.pointer = static_cast<void*>( command ); \
+            }); \
+            aMutex->m_wakeUpMain = true; \
+            aMutex->m_aInMainCondition.notify_all(); \
+        } \
         dispatch_async(dispatch_get_main_queue(),^{ \
             ImplNSAppPostEvent( AquaSalInstance::YieldWakeupEvent, NO ); \
             }); \
-        aMutex->m_aInMainCondition.set(); \
-        osl::Condition::Result res =  aMutex->m_aResultCondition.wait(); \
-        (void) res; \
-        assert(osl::Condition::Result::result_ok == res); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            aMutex->m_aResultCondition.wait( \
+                g, [&aMutex]() { return aMutex->m_resultReady; }); \
+            aMutex->m_resultReady = false; \
+        } \
         return static_cast<type>( aMutex->m_aResult.pointer ); \
     }
 
@@ -107,18 +122,24 @@ union RuninmainResult
     { \
         DBG_TESTSOLARMUTEX(); \
         SalYieldMutex *aMutex = static_cast<SalYieldMutex*>(instance->GetYieldMutex()); \
-        assert( !aMutex->m_aCodeBlock ); \
-        aMutex->m_aCodeBlock = Block_copy(^{ \
-            aMutex->m_aResult.member = command; \
-        }); \
-        aMutex->m_aResultCondition.reset(); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            assert( !aMutex->m_aCodeBlock ); \
+            aMutex->m_aCodeBlock = Block_copy(^{ \
+                aMutex->m_aResult.member = command; \
+            }); \
+            aMutex->m_wakeUpMain = true; \
+            aMutex->m_aInMainCondition.notify_all(); \
+        } \
         dispatch_async(dispatch_get_main_queue(),^{ \
             ImplNSAppPostEvent( AquaSalInstance::YieldWakeupEvent, NO ); \
             }); \
-        aMutex->m_aInMainCondition.set(); \
-        osl::Condition::Result res =  aMutex->m_aResultCondition.wait(); \
-        (void) res; \
-        assert(osl::Condition::Result::result_ok == res); \
+        { \
+            std::unique_lock<std::mutex> g(aMutex->m_runInMainMutex); \
+            aMutex->m_aResultCondition.wait( \
+                g, [&aMutex]() { return aMutex->m_resultReady; }); \
+            aMutex->m_resultReady = false; \
+        } \
         return std::move( aMutex->m_aResult.member ); \
     }
 
diff --git a/vcl/inc/osx/salinst.h b/vcl/inc/osx/salinst.h
index 95dd4db26c24..f96eefaa8950 100644
--- a/vcl/inc/osx/salinst.h
+++ b/vcl/inc/osx/salinst.h
@@ -21,7 +21,11 @@
 #ifndef INCLUDED_VCL_INC_OSX_SALINST_H
 #define INCLUDED_VCL_INC_OSX_SALINST_H
 
+#include <sal/config.h>
+
+#include <condition_variable>
 #include <list>
+#include <mutex>
 
 #include <comphelper/solarmutex.hxx>
 #include <osl/conditn.hxx>