[Libreoffice-commits] core.git: Branch 'distro/collabora/cp-5.0' - vcl/headless vcl/inc

[Tor Lillqvist]

 vcl/headless/svpinst.cxx     |   61 ++++++++++++++++++++++++++++++++-----------
 vcl/inc/headless/svpinst.hxx |    3 ++
 2 files changed, 49 insertions(+), 15 deletions(-)

New commits:
commit 57295468a6770d7831437d83248e68bbe667d86b
Author: Tor Lillqvist <tml at collabora.com>
Date:   Wed Apr 20 13:13:16 2016 +0300

    Don't share the wakeup pipe with child processes
    
    Create a new pipe in the child process.
    
    In a normal desktop LibreOffice each fork() will be followed quickly
    by an exec(), so the FD_CLOEXEC would be enough for that. In
    LibreOfficeKit-based software that uses the preinit mechanism, though,
    the intent is that one can fork child processes without exec().
    
    This solution uses pthread_atfork(). Another way would be to add
    suitable public API callable from the LibreOfficeKit client
    initialisation code in desktop/source/lib/init.cxx to explicitly close
    and reopen the wakeup pipe in the default SvpSalInstance.
    
    Change-Id: I03fad4ce4adf14c16cb0f537b3baab58fba38922
    Reviewed-on: https://gerrit.libreoffice.org/24256
    Reviewed-by: Michael Meeks <michael.meeks at collabora.com>
    Tested-by: Michael Meeks <michael.meeks at collabora.com>

diff --git a/vcl/headless/svpinst.cxx b/vcl/headless/svpinst.cxx
index 7c94f66..0b24718 100644
--- a/vcl/headless/svpinst.cxx
+++ b/vcl/headless/svpinst.cxx
@@ -19,6 +19,7 @@
 
 #include <unistd.h>
 #include <fcntl.h>
+#include <pthread.h>
 #include <sys/time.h>
 #include <sys/poll.h>
 
@@ -62,6 +63,15 @@ bool SvpSalInstance::isFrameAlive( const SalFrame* pFrame ) const
 
 SvpSalInstance* SvpSalInstance::s_pDefaultInstance = NULL;
 
+static void atfork_child()
+{
+    if (SvpSalInstance::s_pDefaultInstance != NULL)
+    {
+        SvpSalInstance::s_pDefaultInstance->CloseWakeupPipe();
+        SvpSalInstance::s_pDefaultInstance->CreateWakeupPipe();
+    }
+}
+
 SvpSalInstance::SvpSalInstance( SalYieldMutex *pMutex ) :
     SalGenericInstance( pMutex )
 {
@@ -70,8 +80,43 @@ SvpSalInstance::SvpSalInstance( SalYieldMutex *pMutex ) :
     m_nTimeoutMS            = 0;
 
     m_pTimeoutFDS[0] = m_pTimeoutFDS[1] = -1;
-    if (pipe (m_pTimeoutFDS) != -1)
+    CreateWakeupPipe();
+    m_aEventGuard = osl_createMutex();
+    if( s_pDefaultInstance == NULL )
+        s_pDefaultInstance = this;
+    pthread_atfork(NULL, NULL, atfork_child);
+}
+
+SvpSalInstance::~SvpSalInstance()
+{
+    if( s_pDefaultInstance == this )
+        s_pDefaultInstance = NULL;
+
+    CloseWakeupPipe();
+    osl_destroyMutex( m_aEventGuard );
+}
+
+void SvpSalInstance::CloseWakeupPipe()
+{
+    if (m_pTimeoutFDS[0] != -1)
     {
+        SAL_INFO("vcl.headless", "CloseWakeupPipe: Closing inherited wakeup pipe: [" << m_pTimeoutFDS[0] << "," << m_pTimeoutFDS[1] << "]");
+        close (m_pTimeoutFDS[0]);
+        close (m_pTimeoutFDS[1]);
+        m_pTimeoutFDS[0] = m_pTimeoutFDS[1] = -1;
+    }
+}
+
+void SvpSalInstance::CreateWakeupPipe()
+{
+    if (pipe (m_pTimeoutFDS) == -1)
+    {
+        SAL_WARN("vcl.headless", "Could not create wakeup pipe: " << strerror(errno));
+    }
+    else
+    {
+        SAL_INFO("vcl.headless", "CreateWakeupPipe: Created wakeup pipe: [" << m_pTimeoutFDS[0] << "," << m_pTimeoutFDS[1] << "]");
+
         // initialize 'wakeup' pipe.
         int flags;
 
@@ -99,20 +144,6 @@ SvpSalInstance::SvpSalInstance( SalYieldMutex *pMutex ) :
             (void)fcntl(m_pTimeoutFDS[1], F_SETFL, flags);
         }
     }
-    m_aEventGuard = osl_createMutex();
-    if( s_pDefaultInstance == NULL )
-        s_pDefaultInstance = this;
-}
-
-SvpSalInstance::~SvpSalInstance()
-{
-    if( s_pDefaultInstance == this )
-        s_pDefaultInstance = NULL;
-
-    // close 'wakeup' pipe.
-    close (m_pTimeoutFDS[0]);
-    close (m_pTimeoutFDS[1]);
-    osl_destroyMutex( m_aEventGuard );
 }
 
 void SvpSalInstance::PostEvent( const SalFrame* pFrame, void* pData, sal_uInt16 nEvent )
diff --git a/vcl/inc/headless/svpinst.hxx b/vcl/inc/headless/svpinst.hxx
index 44795d5..e004a44 100644
--- a/vcl/inc/headless/svpinst.hxx
+++ b/vcl/inc/headless/svpinst.hxx
@@ -97,6 +97,9 @@ public:
     SvpSalInstance( SalYieldMutex *pMutex );
     virtual ~SvpSalInstance();
 
+    void                    CloseWakeupPipe();
+    void                    CreateWakeupPipe();
+
     void                    PostEvent( const SalFrame* pFrame, void* pData, sal_uInt16 nEvent );
 
     bool                    PostedEventsInQueue();