QPID-4330: Windows static destructors: threadSafeShutdown() test

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@1392093 13f79535-47bb-0310-9956-ffa450edef68

10 files changed, 169 insertions, 16 deletions

diff --git a/cpp/src/CMakeLists.txt b/cpp/src/CMakeLists.txt
index 21e82a97b9..299990a6e8 100644
--- a/cpp/src/CMakeLists.txt
+++ b/cpp/src/CMakeLists.txt
@@ -766,6 +766,7 @@ if (CMAKE_SYSTEM_NAME STREQUAL Windows)
   )
   set (qpidclient_platform_SOURCES
     ${sslclient_windows_SOURCES}
+    qpid/client/windows/ClientDllMain.cpp
   )
   set (qpidclient_platform_LIBS
     ${windows_ssl_libs}
diff --git a/cpp/src/Makefile.am b/cpp/src/Makefile.am
index c39dd8114c..45c0d0fb77 100644
--- a/cpp/src/Makefile.am
+++ b/cpp/src/Makefile.am
@@ -25,6 +25,7 @@ SUBDIRS = . tests
 windows_dist = \
   qpid/client/windows/SaslFactory.cpp \
   qpid/client/windows/SslConnector.cpp \
+  qpid/client/windows/ClientDllMain.cpp \
   qpid/log/windows/SinkOptions.cpp \
   qpid/log/windows/SinkOptions.h \
   ../include/qpid/sys/windows/check.h \
@@ -42,6 +43,7 @@ windows_dist = \
   qpid/sys/windows/PollableCondition.cpp \
   qpid/sys/windows/PipeHandle.cpp \
   ../include/qpid/sys/windows/Mutex.h \
+  qpid/sys/windows/QpidDllMain.h \
   qpid/sys/windows/Shlib.cpp \
   qpid/sys/windows/SocketAddress.cpp \
   qpid/sys/windows/Socket.cpp \
diff --git a/cpp/src/qpid/client/ConnectionImpl.cpp b/cpp/src/qpid/client/ConnectionImpl.cpp
index 85b0e8303e..0abfbe09ec 100644
--- a/cpp/src/qpid/client/ConnectionImpl.cpp
+++ b/cpp/src/qpid/client/ConnectionImpl.cpp
@@ -128,15 +128,17 @@ public:
     // and we can't do that before we're unloaded as we can't
     // restart the Poller after shutting it down
     ~IOThread() {
-        std::vector<Thread> threads;
-        {
-            ScopedLock<Mutex> l(threadLock);
-            if (poller_)
-                poller_->shutdown();
-            t.swap(threads);
-        }
-        for (std::vector<Thread>::iterator i = threads.begin(); i != threads.end(); ++i) {
-            i->join();
+        if (SystemInfo::threadSafeShutdown()) {
+            std::vector<Thread> threads;
+            {
+                ScopedLock<Mutex> l(threadLock);
+                if (poller_)
+                    poller_->shutdown();
+                t.swap(threads);
+            }
+            for (std::vector<Thread>::iterator i = threads.begin(); i != threads.end(); ++i) {
+                i->join();
+            }
         }
     }
 };
diff --git a/cpp/src/qpid/client/windows/ClientDllMain.cpp b/cpp/src/qpid/client/windows/ClientDllMain.cpp
new file mode 100644
index 0000000000..d636489908
--- /dev/null
+++ b/cpp/src/qpid/client/windows/ClientDllMain.cpp
@@ -0,0 +1,22 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+#include "qpid/sys/windows/QpidDllMain.h"
diff --git a/cpp/src/qpid/sys/posix/SystemInfo.cpp b/cpp/src/qpid/sys/posix/SystemInfo.cpp
index cfd2c64aee..dea74b4ab0 100755
--- a/cpp/src/qpid/sys/posix/SystemInfo.cpp
+++ b/cpp/src/qpid/sys/posix/SystemInfo.cpp
@@ -205,4 +205,11 @@ string SystemInfo::getProcessName()
     return value;
 }
 
+// Always true.  Only Windows has exception cases.
+bool SystemInfo::threadSafeShutdown()
+{
+    return true;
+}
+
+
 }} // namespace qpid::sys
diff --git a/cpp/src/qpid/sys/solaris/SystemInfo.cpp b/cpp/src/qpid/sys/solaris/SystemInfo.cpp
index e5856f55e6..d4b18e66c8 100755
--- a/cpp/src/qpid/sys/solaris/SystemInfo.cpp
+++ b/cpp/src/qpid/sys/solaris/SystemInfo.cpp
@@ -126,4 +126,10 @@ string SystemInfo::getProcessName()
     return value;
 }
 
+// Always true.  Only Windows has exception cases.
+bool SystemInfo::threadSafeShutdown()
+{
+    return true;
+}
+
 }} // namespace qpid::sys
diff --git a/cpp/src/qpid/sys/windows/QpidDllMain.h b/cpp/src/qpid/sys/windows/QpidDllMain.h
new file mode 100644
index 0000000000..74eaf0256a
--- /dev/null
+++ b/cpp/src/qpid/sys/windows/QpidDllMain.h
@@ -0,0 +1,72 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+
+/*
+ * Include this file once in each DLL that relies on SystemInfo.h:
+ * threadSafeShutdown().  Note that Thread.cpp has a more elaborate
+ * DllMain, that also provides this functionality separately.
+ *
+ * Teardown is in the reverse order of the DLL dependencies used
+ * during the load phase.  The calls to DllMain and the static
+ * destructors are from the same thread, so no locking is necessary
+ * and there is no downside to an invocation of DllMain by multiple
+ * Qpid DLLs.
+ */
+
+#ifdef _DLL
+
+#include <qpid/ImportExport.h>
+#include <windows.h>
+
+namespace qpid {
+namespace sys {
+namespace windows {
+
+QPID_IMPORT bool processExiting;
+QPID_IMPORT bool libraryUnloading;
+
+}}} // namespace qpid::sys::SystemInfo
+
+
+BOOL APIENTRY DllMain(HMODULE hm, DWORD reason, LPVOID reserved) {
+    switch (reason) {
+    case DLL_PROCESS_ATTACH:
+    case DLL_THREAD_ATTACH:
+    case DLL_THREAD_DETACH:
+        break;
+
+    case DLL_PROCESS_DETACH:
+        // Remember how the process is terminating this DLL.
+        if (reserved != NULL) {
+            qpid::sys::windows::processExiting = true;
+            // Danger: all threading suspect, including indirect use of malloc or locks.
+            // Think twice before adding more functionality here.
+            return TRUE;
+        }
+        else {
+            qpid::sys::windows::libraryUnloading = true;
+        }
+        break;
+    }
+    return TRUE;
+}
+
+
+#endif
diff --git a/cpp/src/qpid/sys/windows/Socket.cpp b/cpp/src/qpid/sys/windows/Socket.cpp
index a4374260cc..17e3212a46 100644
--- a/cpp/src/qpid/sys/windows/Socket.cpp
+++ b/cpp/src/qpid/sys/windows/Socket.cpp
@@ -24,6 +24,7 @@
 #include "qpid/sys/SocketAddress.h"
 #include "qpid/sys/windows/check.h"
 #include "qpid/sys/windows/IoHandlePrivate.h"
+#include "qpid/sys/SystemInfo.h"
 
 // Ensure we get all of winsock2.h
 #ifndef _WIN32_WINNT
@@ -67,7 +68,8 @@ public:
     }
 
     ~WinSockSetup() {
-        WSACleanup();
+        if (SystemInfo::threadSafeShutdown())
+            WSACleanup();
     }
 
 public:
diff --git a/cpp/src/qpid/sys/windows/SystemInfo.cpp b/cpp/src/qpid/sys/windows/SystemInfo.cpp
index cef78dcc60..282bbb7e24 100755
--- a/cpp/src/qpid/sys/windows/SystemInfo.cpp
+++ b/cpp/src/qpid/sys/windows/SystemInfo.cpp
@@ -25,7 +25,8 @@
 
 #include "qpid/sys/SystemInfo.h"
 #include "qpid/sys/IntegerTypes.h"
-#include "qpid/Exception.h"

+#include "qpid/Exception.h"
+#include "qpid/log/Statement.h"
 
 #include <assert.h>
 #include <winsock2.h>
@@ -208,4 +209,29 @@ std::string SystemInfo::getProcessName()
     return name;
 }
 
+
+#ifdef _DLL
+namespace windows {
+// set from one or more Qpid DLLs: i.e. in DllMain with DLL_PROCESS_DETACH
+QPID_EXPORT bool processExiting = false;
+QPID_EXPORT bool libraryUnloading = false;
+}
+#endif
+
+bool SystemInfo::threadSafeShutdown()
+{
+#ifdef _DLL
+    if (!windows::processExiting && !windows::libraryUnloading) {
+        // called before exit() or FreeLibrary(), or by a DLL without
+        // a participating DllMain.
+        QPID_LOG(warning, "invalid query for shutdown state");
+        throw qpid::Exception(QPID_MSG("Unable to determine shutdown state."));
+    }
+    return !windows::processExiting;
+#else
+    // Not a DLL: shutdown can only be by exit() or return from main().
+    return false;
+#endif
+}
+
 }} // namespace qpid::sys
diff --git a/cpp/src/qpid/sys/windows/Thread.cpp b/cpp/src/qpid/sys/windows/Thread.cpp
index 23b0033be4..b342c9da1d 100755
--- a/cpp/src/qpid/sys/windows/Thread.cpp
+++ b/cpp/src/qpid/sys/windows/Thread.cpp
@@ -27,6 +27,7 @@
 #include "qpid/sys/Thread.h"
 #include "qpid/sys/Runnable.h"
 #include "qpid/sys/windows/check.h"
+#include "qpid/sys/SystemInfo.h"
 
 #include <process.h>
 #include <windows.h>
@@ -274,8 +275,17 @@ Thread Thread::current() {
 
 #ifdef _DLL
 
+namespace qpid {
+namespace sys {
+namespace windows {
+
+extern bool processExiting;
+extern bool libraryUnloading;
+
+}}} // namespace qpid::sys::SystemInfo
+
 // DllMain: called possibly many times in a process lifetime if dll
-// loaded and freed repeatedly .  Be mindful of Windows loader lock
+// loaded and freed repeatedly.  Be mindful of Windows loader lock
 // and other DllMain restrictions.
 
 BOOL APIENTRY DllMain(HMODULE hm, DWORD reason, LPVOID reserved) {
@@ -290,10 +300,12 @@ BOOL APIENTRY DllMain(HMODULE hm, DWORD reason, LPVOID reserved) {
         if (reserved != NULL) {
             // process exit(): threads are stopped arbitrarily and
             // possibly in an inconsistent state.  Not even threadLock
-            // can be trusted.  All static destructors have been
-            // called at this point and any resources this unit knows
-            // about will be released as part of process tear down by
-            // the OS.  Accordingly, do nothing.
+            // can be trusted.  All static destructors for this unit
+            // are pending and face the same unsafe environment.
+            // Any resources this unit knows about will be released as
+            // part of process tear down by the OS.  Accordingly, skip
+            // any clean up tasks.
+            qpid::sys::windows::processExiting = true;
             return TRUE;
         }
         else {
@@ -301,6 +313,7 @@ BOOL APIENTRY DllMain(HMODULE hm, DWORD reason, LPVOID reserved) {
             // encouraged to clean up to avoid leaks.  Mostly we just
             // want any straggler threads to finish and notify
             // threadsDone as the last thing they do.
+            qpid::sys::windows::libraryUnloading = true;
             while (1) {
                 {
                     ScopedCriticalSection l(threadLock);