lok: join Webdav Ticker thread.

Add 'startThreads' lok method for the few thread scenarios where
we need to have a background thread running that cannot be started
opportunistically.

Also add that to the ThreadJoinable interface so we can get into
UNO components' implementations to handle their worker threads
easily.

Implement joining and re-starting in WebDAV ucp too.

Change-Id: I329ef9decb32b263197e4c03a0d54952985fdd0e
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/167858
Reviewed-by: Michael Meeks <michael.meeks@collabora.com>
Reviewed-by: Caolán McNamara <caolan.mcnamara@collabora.com>
Tested-by: Jenkins CollaboraOffice <jenkinscollaboraoffice@gmail.com>

9 files changed, 117 insertions, 14 deletions

diff --git a/desktop/qa/desktop_lib/test_desktop_lib.cxx b/desktop/qa/desktop_lib/test_desktop_lib.cxx
index 298e5a5d7a9b..4a09b10931f6 100644
--- a/desktop/qa/desktop_lib/test_desktop_lib.cxx
+++ b/desktop/qa/desktop_lib/test_desktop_lib.cxx
@@ -3594,11 +3594,12 @@ void DesktopLOKTest::testABI()
     CPPUNIT_ASSERT_EQUAL(classOffset(18), offsetof(struct _LibreOfficeKitClass, startURP));
     CPPUNIT_ASSERT_EQUAL(classOffset(19), offsetof(struct _LibreOfficeKitClass, stopURP));
     CPPUNIT_ASSERT_EQUAL(classOffset(20), offsetof(struct _LibreOfficeKitClass, joinThreads));
-    CPPUNIT_ASSERT_EQUAL(classOffset(21), offsetof(struct _LibreOfficeKitClass, setForkedChild));
+    CPPUNIT_ASSERT_EQUAL(classOffset(21), offsetof(struct _LibreOfficeKitClass, startThreads));
+    CPPUNIT_ASSERT_EQUAL(classOffset(22), offsetof(struct _LibreOfficeKitClass, setForkedChild));
 
     // When extending LibreOfficeKit with a new function pointer,  add new assert for the offsetof the
     // new function pointer and bump this assert for the size of the class.
-    CPPUNIT_ASSERT_EQUAL(classOffset(22), sizeof(struct _LibreOfficeKitClass));
+    CPPUNIT_ASSERT_EQUAL(classOffset(23), sizeof(struct _LibreOfficeKitClass));
 
     CPPUNIT_ASSERT_EQUAL(documentClassOffset(0), offsetof(struct _LibreOfficeKitDocumentClass, destroy));
     CPPUNIT_ASSERT_EQUAL(documentClassOffset(1), offsetof(struct _LibreOfficeKitDocumentClass, saveAs));
diff --git a/desktop/source/lib/init.cxx b/desktop/source/lib/init.cxx
index f00edb9ec9c9..86f0efda8857 100644
--- a/desktop/source/lib/init.cxx
+++ b/desktop/source/lib/init.cxx
@@ -2602,6 +2602,8 @@ static void lo_stopURP(LibreOfficeKit* pThis, void* pSendURPToLOContext);
 
 static int lo_joinThreads(LibreOfficeKit* pThis);
 
+static void lo_startThreads(LibreOfficeKit* pThis);
+
 static void lo_setForkedChild(LibreOfficeKit* pThis, bool bIsChild);
 
 static void lo_runLoop(LibreOfficeKit* pThis,
@@ -2649,6 +2651,7 @@ LibLibreOffice_Impl::LibLibreOffice_Impl()
         m_pOfficeClass->startURP = lo_startURP;
         m_pOfficeClass->stopURP = lo_stopURP;
         m_pOfficeClass->joinThreads = lo_joinThreads;
+        m_pOfficeClass->startThreads = lo_startThreads;
         m_pOfficeClass->setForkedChild = lo_setForkedChild;
 
         gOfficeClass = m_pOfficeClass;
@@ -3399,6 +3402,12 @@ static int lo_joinThreads(LibreOfficeKit* /* pThis */)
     if (joinable && !joinable->joinThreads())
         return 0;
 
+    auto ucpWebdav = xContext->getServiceManager()->createInstanceWithContext(
+        "com.sun.star.ucb.WebDAVManager", xContext);
+    joinable = dynamic_cast<comphelper::LibreOfficeKit::ThreadJoinable *>(ucpWebdav.get());
+    if (joinable && !joinable->joinThreads())
+        return 0;
+
     // Ensure configmgr's write thread is down
     css::uno::Reference< css::util::XFlushable >(
         css::configuration::theDefaultProvider::get(
@@ -3408,6 +3417,15 @@ static int lo_joinThreads(LibreOfficeKit* /* pThis */)
     return 1;
 }
 
+static void lo_startThreads(LibreOfficeKit* /* pThis */)
+{
+    auto ucpWebdav = xContext->getServiceManager()->createInstanceWithContext(
+        "com.sun.star.ucb.WebDAVManager", xContext);
+    auto joinable = dynamic_cast<comphelper::LibreOfficeKit::ThreadJoinable *>(ucpWebdav.get());
+    if (joinable)
+        joinable->startThreads();
+}
+
 static void lo_setForkedChild(LibreOfficeKit* /* pThis */, bool bIsChild)
 {
     comphelper::LibreOfficeKit::setForkedChild(bIsChild);
diff --git a/include/LibreOfficeKit/LibreOfficeKit.h b/include/LibreOfficeKit/LibreOfficeKit.h
index f57c7ad32843..2a0df3348f8d 100644
--- a/include/LibreOfficeKit/LibreOfficeKit.h
+++ b/include/LibreOfficeKit/LibreOfficeKit.h
@@ -144,6 +144,9 @@ struct _LibreOfficeKitClass
     /// @see lok::Office::joinThreads
     int (*joinThreads)(LibreOfficeKit* pThis);
 
+    /// @see lok::Office::startThreads
+    void (*startThreads)(LibreOfficeKit* pThis);
+
     /// @see lok::Office::setForkedChild
     void (*setForkedChild)(LibreOfficeKit* pThis, bool bIsChild);
 };
diff --git a/include/LibreOfficeKit/LibreOfficeKit.hxx b/include/LibreOfficeKit/LibreOfficeKit.hxx
index af9ccd12ab2f..14ad6a86f913 100644
--- a/include/LibreOfficeKit/LibreOfficeKit.hxx
+++ b/include/LibreOfficeKit/LibreOfficeKit.hxx
@@ -1224,6 +1224,15 @@ public:
     }
 
     /**
+     * Starts all threads that are necessary to continue working
+     * after a joinThreads().
+     */
+    void startThreads()
+    {
+        mpThis->pClass->startThreads(mpThis);
+    }
+
+    /**
      * Informs that this process is either a parent, or a child
      * process post-fork, allowing improved resource sharing.
      */
diff --git a/include/comphelper/lok.hxx b/include/comphelper/lok.hxx
index 555b749fa6a1..f998c12dedc3 100644
--- a/include/comphelper/lok.hxx
+++ b/include/comphelper/lok.hxx
@@ -26,6 +26,8 @@ class COMPHELPER_DLLPUBLIC SAL_LOPLUGIN_ANNOTATE("crosscast") ThreadJoinable
 public:
     /// shutdown and join threads, @returns true on success
     virtual bool joinThreads() = 0;
+    /// restart any required threads, usually are demand-restarted
+    virtual void startThreads() {}
 };
 
 // Functions to be called only from the LibreOfficeKit implementation in desktop, not from other
diff --git a/ucb/source/ucp/webdav-curl/CurlSession.cxx b/ucb/source/ucp/webdav-curl/CurlSession.cxx
index e60bd6ef1d36..a80c19f6d690 100644
--- a/ucb/source/ucp/webdav-curl/CurlSession.cxx
+++ b/ucb/source/ucp/webdav-curl/CurlSession.cxx
@@ -14,9 +14,13 @@
 #include "UCBDeadPropertyValue.hxx"
 #include "webdavresponseparser.hxx"
 
+#include <cppuhelper/implbase.hxx>
+#include <comphelper/processfactory.hxx>
 #include <comphelper/attributelist.hxx>
 #include <comphelper/scopeguard.hxx>
 #include <comphelper/string.hxx>
+#include <cppuhelper/queryinterface.hxx>
+#include <cppuhelper/supportsservice.hxx>
 
 #include <o3tl/safeint.hxx>
 #include <o3tl/string_view.hxx>
@@ -26,6 +30,7 @@
 
 #include <com/sun/star/beans/NamedValue.hpp>
 #include <com/sun/star/io/Pipe.hpp>
+#include <com/sun/star/lang/XServiceInfo.hpp>
 #include <com/sun/star/io/SequenceInputStream.hpp>
 #include <com/sun/star/io/SequenceOutputStream.hpp>
 #include <com/sun/star/xml/sax/Writer.hpp>
@@ -2430,4 +2435,42 @@ auto CurlSession::NonInteractive_UNLOCK(OUString const& rURI) -> void
 
 } // namespace http_dav_ucp
 
+namespace
+{
+/// Manage lifecycle of global DAV worker threads
+class WebDAVManager : public cppu::WeakImplHelper<css::lang::XServiceInfo>,
+                      public comphelper::LibreOfficeKit::ThreadJoinable
+{
+public:
+    WebDAVManager() {}
+
+    // XServiceInfo
+    virtual OUString SAL_CALL getImplementationName() override
+    {
+        return "com.sun.star.comp.WebDAVManager";
+    }
+    virtual sal_Bool SAL_CALL supportsService(const OUString& ServiceName) override
+    {
+        return cppu::supportsService(this, ServiceName);
+    }
+    virtual css::uno::Sequence<OUString> SAL_CALL getSupportedServiceNames() override
+    {
+        return { "com.sun.star.ucb.WebDAVManager" };
+    }
+
+    // comphelper::LibreOfficeKit::ThreadJoinable
+    virtual bool joinThreads() override { return g_Init.LockStore.joinThreads(); }
+
+    virtual void startThreads() override { g_Init.LockStore.startThreads(); }
+};
+
+} // anonymous namespace
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*
+ucb_webdav_manager_get_implementation(css::uno::XComponentContext*,
+                                      css::uno::Sequence<css::uno::Any> const&)
+{
+    return cppu::acquire(new WebDAVManager());
+}
+
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/ucb/source/ucp/webdav-curl/SerfLockStore.cxx b/ucb/source/ucp/webdav-curl/SerfLockStore.cxx
index 6d7b89e9e687..cfa6f666b056 100644
--- a/ucb/source/ucp/webdav-curl/SerfLockStore.cxx
+++ b/ucb/source/ucp/webdav-curl/SerfLockStore.cxx
@@ -101,10 +101,8 @@ SerfLockStore::~SerfLockStore()
     }
 }
 
-void SerfLockStore::startTicker()
+void SerfLockStore::startTicker(std::unique_lock<std::mutex> & /* rGuard is held */)
 {
-    std::unique_lock aGuard( m_aMutex );
-
     if ( !m_pTickerThread.is() )
     {
         m_pTickerThread = new TickerThread( *this );
@@ -112,7 +110,6 @@ void SerfLockStore::startTicker()
     }
 }
 
-
 void SerfLockStore::stopTicker(std::unique_lock<std::mutex> & rGuard)
 {
     rtl::Reference<TickerThread> pTickerThread;
@@ -122,6 +119,7 @@ void SerfLockStore::stopTicker(std::unique_lock<std::mutex> & rGuard)
         m_pTickerThread->finish(); // needs mutex
         // the TickerThread may run refreshLocks() at most once after this
         pTickerThread = m_pTickerThread;
+
         m_pTickerThread.clear();
     }
 
@@ -133,6 +131,25 @@ void SerfLockStore::stopTicker(std::unique_lock<std::mutex> & rGuard)
     }
 }
 
+bool SerfLockStore::joinThreads()
+{
+    std::unique_lock aGuard(m_aMutex);
+    // FIXME: cure could be worse than the problem; we don't
+    // want to block on a long-standing webdav lock refresh request.
+    // perhaps we should timeout on a condition instead if a request
+    // is in progress.
+    if (m_pTickerThread.is())
+        stopTicker(aGuard);
+    return true;
+}
+
+void SerfLockStore::startThreads()
+{
+    std::unique_lock aGuard( m_aMutex );
+    if (!m_aLockInfoMap.empty())
+        startTicker(aGuard);
+}
+
 OUString const*
 SerfLockStore::getLockTokenForURI(OUString const& rURI, css::ucb::Lock const*const pLock)
 {
@@ -175,14 +192,12 @@ void SerfLockStore::addLock( const OUString& rURI,
                              sal_Int32 nLastChanceToSendRefreshRequest )
 {
     assert(rURI.startsWith("http://") || rURI.startsWith("https://"));
-    {
-        std::unique_lock aGuard( m_aMutex );
+    std::unique_lock aGuard( m_aMutex );
 
-        m_aLockInfoMap[ rURI ]
-            = LockInfo(sToken, rLock, xSession, nLastChanceToSendRefreshRequest);
-    }
+    m_aLockInfoMap[ rURI ]
+        = LockInfo(sToken, rLock, xSession, nLastChanceToSendRefreshRequest);
 
-    startTicker();
+    startTicker(aGuard);
 }
 
 
diff --git a/ucb/source/ucp/webdav-curl/SerfLockStore.hxx b/ucb/source/ucp/webdav-curl/SerfLockStore.hxx
index 8b54901e1fb8..08a88746b0d0 100644
--- a/ucb/source/ucp/webdav-curl/SerfLockStore.hxx
+++ b/ucb/source/ucp/webdav-curl/SerfLockStore.hxx
@@ -26,6 +26,7 @@
 #include <rtl/ustring.hxx>
 #include <com/sun/star/ucb/Lock.hpp>
 #include <utility>
+#include <comphelper/lok.hxx>
 
 #include "CurlSession.hxx"
 
@@ -57,7 +58,7 @@ struct LockInfo
 
 typedef std::map< OUString, LockInfo > LockInfoMap;
 
-class SerfLockStore
+class SerfLockStore : public comphelper::LibreOfficeKit::ThreadJoinable
 {
     std::mutex         m_aMutex;
     rtl::Reference< TickerThread > m_pTickerThread;
@@ -81,9 +82,16 @@ public:
 
     void refreshLocks();
 
+    void joinThread();
+    void restartThread();
+
+    // comphelper::LibreOfficeKit::ThreadJoinable
+    virtual bool joinThreads() override;
+    virtual void startThreads() override;
+
 private:
     void removeLockImpl(std::unique_lock<std::mutex> & rGuard, const OUString& rURI);
-    void startTicker();
+    void startTicker(std::unique_lock<std::mutex> & rGuard);
     void stopTicker(std::unique_lock<std::mutex> & rGuard);
 };
 
diff --git a/ucb/source/ucp/webdav-curl/ucpdav1.component b/ucb/source/ucp/webdav-curl/ucpdav1.component
index bb16e3b3979d..678e860c1178 100644
--- a/ucb/source/ucp/webdav-curl/ucpdav1.component
+++ b/ucb/source/ucp/webdav-curl/ucpdav1.component
@@ -23,4 +23,8 @@
     constructor="ucb_webdav_ContentProvider_get_implementation">
     <service name="com.sun.star.ucb.WebDAVContentProvider"/>
   </implementation>
+  <implementation name="com.sun.star.comp.WebDAVManager"
+    constructor="ucb_webdav_manager_get_implementation" single-instance="true">
+    <service name="com.sun.star.ucb.WebDAVManager"/>
+  </implementation>
 </component>