undoing accidental deletion

1 files changed, 614 insertions, 0 deletions

diff --git a/ACE/ace/Sig_Handler.cpp b/ACE/ace/Sig_Handler.cpp
new file mode 100644
index 00000000000..37d8de90bc6
--- /dev/null
+++ b/ACE/ace/Sig_Handler.cpp
@@ -0,0 +1,614 @@
+// $Id$
+
+#include "ace/Sig_Handler.h"
+#include "ace/Sig_Adapter.h"
+#include "ace/Signal.h"
+#include "ace/Recursive_Thread_Mutex.h"
+#include "ace/Managed_Object.h"
+#include "ace/Containers.h"
+#include "ace/Guard_T.h"
+
+#if !defined (__ACE_INLINE__)
+#include "ace/Sig_Handler.inl"
+#endif /* __ACE_INLINE__ */
+
+ACE_RCSID(ace, Sig_Handler, "$Id$")
+
+#if defined (ACE_HAS_SIG_C_FUNC)
+
+extern "C" void
+ace_sig_handler_dispatch (int signum, siginfo_t *info, ucontext_t *context)
+{
+  ACE_TRACE ("ace_sig_handler_dispatch");
+  ACE_Sig_Handler::dispatch (signum, info, context);
+}
+
+#define ace_signal_handler_dispatcher ACE_SignalHandler(ace_sig_handler_dispatch)
+
+extern "C" void
+ace_sig_handlers_dispatch (int signum, siginfo_t *info, ucontext_t *context)
+{
+  ACE_TRACE ("ace_sig_handlers_dispatch");
+  ACE_Sig_Handlers::dispatch (signum, info, context);
+}
+
+#define ace_signal_handlers_dispatcher ACE_SignalHandler(ace_sig_handlers_dispatch)
+
+#else
+#define ace_signal_handler_dispatcher ACE_SignalHandler(ACE_Sig_Handler::dispatch)
+
+#define ace_signal_handlers_dispatcher ACE_SignalHandler(ACE_Sig_Handlers::dispatch)
+#endif /* ACE_HAS_SIG_C_FUNC */
+
+
+ACE_BEGIN_VERSIONED_NAMESPACE_DECL
+
+// Array of Event_Handlers that will handle the signals.
+ACE_Event_Handler *ACE_Sig_Handler::signal_handlers_[ACE_NSIG];
+
+// Remembers if a signal has occurred.
+sig_atomic_t ACE_Sig_Handler::sig_pending_ = 0;
+
+
+ACE_ALLOC_HOOK_DEFINE(ACE_Sig_Handler)
+
+ACE_Sig_Handler::~ACE_Sig_Handler (void)
+{
+}
+
+void
+ACE_Sig_Handler::dump (void) const
+{
+#if defined (ACE_HAS_DUMP)
+  ACE_TRACE ("ACE_Sig_Handler::dump");
+#endif /* ACE_HAS_DUMP */
+}
+
+int
+ACE_Sig_Handler::sig_pending (void)
+{
+  ACE_TRACE ("ACE_Sig_Handler::sig_pending");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+          ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+          (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+          ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+  return ACE_Sig_Handler::sig_pending_ != 0;
+}
+
+void
+ACE_Sig_Handler::sig_pending (int pending)
+{
+  ACE_TRACE ("ACE_Sig_Handler::sig_pending");
+
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+          ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+          (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+          ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+  ACE_Sig_Handler::sig_pending_ = pending;
+}
+
+ACE_Event_Handler *
+ACE_Sig_Handler::handler (int signum)
+{
+  ACE_TRACE ("ACE_Sig_Handler::handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  if (ACE_Sig_Handler::in_range (signum))
+    return ACE_Sig_Handler::signal_handlers_[signum];
+  else
+    return 0;
+}
+
+ACE_Event_Handler *
+ACE_Sig_Handler::handler_i (int signum,
+                            ACE_Event_Handler *new_sh)
+{
+  ACE_TRACE ("ACE_Sig_Handler::handler_i");
+
+  if (ACE_Sig_Handler::in_range (signum))
+    {
+      ACE_Event_Handler *sh = ACE_Sig_Handler::signal_handlers_[signum];
+
+      ACE_Sig_Handler::signal_handlers_[signum] = new_sh;
+      return sh;
+    }
+  else
+    return 0;
+}
+
+ACE_Event_Handler *
+ACE_Sig_Handler::handler (int signum,
+                          ACE_Event_Handler *new_sh)
+{
+  ACE_TRACE ("ACE_Sig_Handler::handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  return ACE_Sig_Handler::handler_i (signum, new_sh);
+}
+
+// Register an ACE_Event_Handler along with the corresponding SIGNUM.
+// This method does NOT acquire any locks, so it can be called from a
+// signal handler.
+
+int
+ACE_Sig_Handler::register_handler_i (int signum,
+                                     ACE_Event_Handler *new_sh,
+                                     ACE_Sig_Action *new_disp,
+                                     ACE_Event_Handler **old_sh,
+                                     ACE_Sig_Action *old_disp)
+{
+  ACE_TRACE ("ACE_Sig_Handler::register_handler_i");
+
+  if (ACE_Sig_Handler::in_range (signum))
+    {
+      ACE_Sig_Action sa; // Define a "null" action.
+      ACE_Event_Handler *sh = ACE_Sig_Handler::handler_i (signum,
+                                                          new_sh);
+
+      // Return a pointer to the old <ACE_Sig_Handler> if the user
+      // asks for this.
+      if (old_sh != 0)
+        *old_sh = sh;
+
+      // Make sure that <new_disp> points to a valid location if the
+      // user doesn't care...
+      if (new_disp == 0)
+        new_disp = &sa;
+
+      new_disp->handler (ace_signal_handler_dispatcher);
+#if !defined (ACE_HAS_LYNXOS_SIGNALS)
+      new_disp->flags (new_disp->flags () | SA_SIGINFO);
+#endif /* ACE_HAS_LYNXOS_SIGNALS */
+      return new_disp->register_action (signum, old_disp);
+    }
+  else
+    return -1;
+}
+
+// Register an ACE_Event_Handler along with the corresponding SIGNUM.
+// This method acquires a lock, so it can't be called from a signal
+// handler, e.g., <dispatch>.
+
+int
+ACE_Sig_Handler::register_handler (int signum,
+                                   ACE_Event_Handler *new_sh,
+                                   ACE_Sig_Action *new_disp,
+                                   ACE_Event_Handler **old_sh,
+                                   ACE_Sig_Action *old_disp)
+{
+  ACE_TRACE ("ACE_Sig_Handler::register_handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  return ACE_Sig_Handler::register_handler_i (signum,
+                                              new_sh,
+                                              new_disp,
+                                              old_sh,
+                                              old_disp);
+}
+
+// Remove an ACE_Event_Handler.
+
+int
+ACE_Sig_Handler::remove_handler (int signum,
+                                 ACE_Sig_Action *new_disp,
+                                 ACE_Sig_Action *old_disp,
+                                 int)
+{
+  ACE_TRACE ("ACE_Sig_Handler::remove_handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  if (ACE_Sig_Handler::in_range (signum))
+    {
+      ACE_Sig_Action sa (SIG_DFL, (sigset_t *) 0); // Define the default disposition.
+
+      if (new_disp == 0)
+        new_disp = &sa;
+
+      ACE_Sig_Handler::signal_handlers_[signum] = 0;
+
+      // Register either the new disposition or restore the default.
+      return new_disp->register_action (signum, old_disp);
+    }
+
+    return -1;
+}
+
+// Master dispatcher function that gets called by a signal handler and
+// dispatches one handler...
+
+void
+ACE_Sig_Handler::dispatch (int signum,
+                           siginfo_t *siginfo,
+                           ucontext_t *ucontext)
+{
+  ACE_TRACE ("ACE_Sig_Handler::dispatch");
+
+  // Save/restore errno.
+  ACE_Errno_Guard error (errno);
+
+  // We can't use the <sig_pending> call here because that acquires
+  // the lock, which is non-portable...
+  ACE_Sig_Handler::sig_pending_ = 1;
+
+  // Darn well better be in range since the OS dispatched this...
+  ACE_ASSERT (ACE_Sig_Handler::in_range (signum));
+
+  ACE_Event_Handler *eh = ACE_Sig_Handler::signal_handlers_[signum];
+
+  if (eh != 0)
+    {
+      if (eh->handle_signal (signum, siginfo, ucontext) == -1)
+        {
+          // Define the default disposition.
+          ACE_Sig_Action sa ((ACE_SignalHandler) SIG_DFL, (sigset_t *) 0);
+
+          ACE_Sig_Handler::signal_handlers_[signum] = 0;
+
+          // Remove the current disposition by registering the default
+          // disposition.
+          sa.register_action (signum);
+
+          // Allow the event handler to close down if necessary.
+          eh->handle_close (ACE_INVALID_HANDLE,
+                            ACE_Event_Handler::SIGNAL_MASK);
+        }
+#if defined (ACE_WIN32)
+      else
+        // Win32 is weird in the sense that it resets the signal
+        // disposition to SIG_DFL after a signal handler is
+        // dispatched.  Therefore, to workaround this "feature" we
+        // must re-register the <ACE_Event_Handler> with <signum>
+        // explicitly.
+        ACE_Sig_Handler::register_handler_i (signum,
+                                             eh);
+#endif /* ACE_WIN32*/
+    }
+}
+
+// ----------------------------------------
+// The following classes are local to this file.
+
+// There are bugs with HP/UX's C++ compiler that prevents this stuff
+// from compiling...
+#define ACE_MAX_SIGNAL_HANDLERS ((size_t) 20)
+
+// Keeps track of the id that uniquely identifies each registered
+// signal handler.  This id can be used to cancel a timer via the
+// <remove_handler> method.
+int ACE_Sig_Handlers::sigkey_ = 0;
+
+// If this is > 0 then a 3rd party library has registered a
+// handler...
+int ACE_Sig_Handlers::third_party_sig_handler_ = 0;
+
+// Make life easier by defining typedefs...
+typedef ACE_Fixed_Set <ACE_Event_Handler *, ACE_MAX_SIGNAL_HANDLERS> ACE_SIG_HANDLERS_SET;
+typedef ACE_Fixed_Set_Iterator <ACE_Event_Handler *, ACE_MAX_SIGNAL_HANDLERS> ACE_SIG_HANDLERS_ITERATOR;
+
+class ACE_Sig_Handlers_Set
+{
+public:
+  static ACE_SIG_HANDLERS_SET *instance (int signum);
+
+private:
+  static ACE_SIG_HANDLERS_SET *sig_handlers_[ACE_NSIG];
+};
+
+/* static */
+ACE_SIG_HANDLERS_SET *ACE_Sig_Handlers_Set::sig_handlers_[ACE_NSIG];
+
+/* static */
+ACE_SIG_HANDLERS_SET *
+ACE_Sig_Handlers_Set::instance (int signum)
+{
+  if (signum <= 0 || signum >= ACE_NSIG)
+    return 0; // This will cause problems...
+  else if (ACE_Sig_Handlers_Set::sig_handlers_[signum] == 0)
+    ACE_NEW_RETURN (ACE_Sig_Handlers_Set::sig_handlers_[signum],
+                    ACE_SIG_HANDLERS_SET,
+                    0);
+  return ACE_Sig_Handlers_Set::sig_handlers_[signum];
+}
+
+ACE_ALLOC_HOOK_DEFINE(ACE_Sig_Handlers)
+
+void
+ACE_Sig_Handlers::dump (void) const
+{
+#if defined (ACE_HAS_DUMP)
+  ACE_TRACE ("ACE_Sig_Handlers::dump");
+#endif /* ACE_HAS_DUMP */
+}
+
+// This is the method that does all the dirty work...  The basic
+// structure of this method was devised by Detlef Becker.
+
+int
+ACE_Sig_Handlers::register_handler (int signum,
+                                    ACE_Event_Handler *new_sh,
+                                    ACE_Sig_Action *new_disp,
+                                    ACE_Event_Handler **,
+                                    ACE_Sig_Action *old_disp)
+{
+  ACE_TRACE ("ACE_Sig_Handlers::register_handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  if (ACE_Sig_Handler::in_range (signum))
+    {
+      ACE_Sig_Adapter *ace_sig_adapter = 0; // Our signal handler.
+      ACE_Sig_Adapter *extern_sh = 0; // An external signal handler.
+      ACE_Sig_Action sa;
+
+      // Get current signal disposition.
+      sa.retrieve_action (signum);
+
+      // Check whether we are already in control of the signal
+      // handling disposition...
+
+      if (!(sa.handler () == ace_signal_handlers_dispatcher
+          || sa.handler () == ACE_SignalHandler (SIG_IGN)
+          || sa.handler () == ACE_SignalHandler (SIG_DFL)))
+        {
+          // Drat, a 3rd party library has already installed a signal ;-(
+
+          // Upto here we never disabled RESTART_MODE.  Thus,
+          // RESTART_MODE can only be changed by 3rd party libraries.
+
+          if (ACE_BIT_DISABLED (sa.flags (), SA_RESTART)
+              && ACE_Sig_Handlers::third_party_sig_handler_)
+            // Toggling is disallowed since we might break 3rd party
+            // code.
+            return -1;
+
+          // Note that we've seen a 3rd party handler...
+          ACE_Sig_Handlers::third_party_sig_handler_ = 1;
+
+          // Create a new 3rd party disposition, remembering its
+          // preferred signal blocking etc...;
+          ACE_NEW_RETURN (extern_sh,
+                          ACE_Sig_Adapter (sa,
+                                           ++ACE_Sig_Handlers::sigkey_),
+                          -1);
+          // Add the external signal handler to the set of handlers
+          // for this signal.
+          if (ACE_Sig_Handlers_Set::instance (signum)->insert (extern_sh) == -1)
+            {
+              delete extern_sh;
+              return -1;
+            }
+        }
+      // Add our new handler at this point.
+      ACE_NEW_RETURN (ace_sig_adapter,
+                      ACE_Sig_Adapter (new_sh,
+                                       ++ACE_Sig_Handlers::sigkey_),
+                      -1);
+      // Add the ACE signal handler to the set of handlers for this
+      // signal (make sure it goes before the external one if there is
+      // one of these).
+      if (ACE_Sig_Handlers_Set::instance (signum)->insert (ace_sig_adapter) == -1)
+        {
+          // We couldn't reinstall our handler, so let's pretend like
+          // none of this happened...
+          if (extern_sh)
+            {
+              ACE_Sig_Handlers_Set::instance (signum)->remove (extern_sh);
+              delete extern_sh;
+            }
+          delete ace_sig_adapter;
+          return -1;
+        }
+      // If ACE_Sig_Handlers::dispatch() was set we're done.
+      else if (sa.handler () == ace_signal_handlers_dispatcher)
+        return ace_sig_adapter->sigkey ();
+
+      // Otherwise, we need to register our handler function so that
+      // all signals will be dispatched through ACE.
+      else
+        {
+          // Make sure that new_disp points to a valid location if the
+          // user doesn't care...
+          if (new_disp == 0)
+            new_disp = &sa;
+
+          new_disp->handler (ace_signal_handlers_dispatcher);
+
+          // Default is to restart signal handlers.
+          new_disp->flags (new_disp->flags () | SA_RESTART);
+          new_disp->flags (new_disp->flags () | SA_SIGINFO);
+
+          // Finally install (possibly reinstall) the ACE signal
+          // handler disposition with the SA_RESTART mode enabled.
+          if (new_disp->register_action (signum, old_disp) == -1)
+            {
+              // Yikes, lots of roll back at this point...
+              ACE_Sig_Handlers_Set::instance (signum)->remove (ace_sig_adapter);
+              delete ace_sig_adapter;
+
+              if (extern_sh)
+                {
+                  ACE_Sig_Handlers_Set::instance (signum)->remove (extern_sh);
+                  delete extern_sh;
+                }
+              return -1;
+            }
+          else // Return the signal key so that programs can cancel this
+            // handler if they want!
+            return ace_sig_adapter->sigkey ();
+        }
+    }
+
+  return -1;
+}
+
+// Remove the ACE_Event_Handler currently associated with <signum>.
+// Install the new disposition (if given) and return the previous
+// disposition (if desired by the caller).  Returns 0 on success and
+// -1 if <signum> is invalid.
+
+int
+ACE_Sig_Handlers::remove_handler (int signum,
+                                  ACE_Sig_Action *new_disp,
+                                  ACE_Sig_Action *old_disp,
+                                  int sigkey)
+{
+  ACE_TRACE ("ACE_Sig_Handlers::remove_handler");
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+
+  if (ACE_Sig_Handler::in_range (signum))
+    {
+      ACE_SIG_HANDLERS_SET *handler_set =
+        ACE_Sig_Handlers_Set::instance (signum);
+
+      ACE_SIG_HANDLERS_ITERATOR handler_iterator (*handler_set);
+
+      // Iterate through the set of handlers for this signal.
+
+      for (ACE_Event_Handler **eh;
+           handler_iterator.next (eh) != 0;
+           handler_iterator.advance ())
+        {
+          // Type-safe downcast would be nice here...
+          ACE_Sig_Adapter *sh = (ACE_Sig_Adapter *) *eh;
+
+          // Remove the handler if (1) its key matches the key we've
+          // been told to remove or (2) if we've been told to remove
+          // *all* handlers (i.e., <sigkey> == -1).
+
+          if (sh->sigkey () == sigkey || sigkey == -1)
+            {
+              handler_set->remove (*eh);
+              delete *eh;
+            }
+        }
+
+      if (handler_set->size () == 0)
+        {
+          // If there are no more handlers left for a signal then
+          // register the new disposition or restore the default
+          // disposition.
+
+          ACE_Sig_Action sa (SIG_DFL, (sigset_t *) 0);
+
+          if (new_disp == 0)
+            new_disp = &sa;
+
+          return new_disp->register_action (signum, old_disp);
+        }
+      return 0;
+    }
+  else
+    return -1;
+}
+
+// Master dispatcher function that gets called by a signal handler and
+// dispatches *all* the handlers...
+
+void
+ACE_Sig_Handlers::dispatch (int signum,
+                            siginfo_t *siginfo,
+                            ucontext_t *ucontext)
+{
+  ACE_TRACE ("ACE_Sig_Handlers::dispatch");
+  // The following is #ifdef'd out because it's entirely non-portable
+  // to acquire a mutex in a signal handler...
+#if 0
+  ACE_MT (ACE_Recursive_Thread_Mutex *lock =
+    ACE_Managed_Object<ACE_Recursive_Thread_Mutex>::get_preallocated_object
+      (ACE_Object_Manager::ACE_SIG_HANDLER_LOCK);
+    ACE_TSS_Guard<ACE_Recursive_Thread_Mutex> m (*lock));
+#endif /* 0 */
+
+  // Save/restore errno.
+  ACE_Errno_Guard error (errno);
+
+  ACE_Sig_Handler::sig_pending_ = 1;
+
+  // Darn well better be in range since the OS dispatched this...
+  ACE_ASSERT (ACE_Sig_Handler::in_range (signum));
+
+  ACE_SIG_HANDLERS_SET *handler_set =
+    ACE_Sig_Handlers_Set::instance (signum);
+
+  ACE_SIG_HANDLERS_ITERATOR handler_iterator (*handler_set);
+
+  for (ACE_Event_Handler **eh = 0;
+       handler_iterator.next (eh) != 0;
+       handler_iterator.advance ())
+    {
+      if ((*eh)->handle_signal (signum, siginfo, ucontext) == -1)
+        {
+          handler_set->remove (*eh);
+          delete *eh;
+        }
+    }
+}
+
+// Return the first item in the list of handlers.  Note that this will
+// trivially provide the same behavior as the ACE_Sig_Handler
+// version if there is only 1 handler registered!
+
+ACE_Event_Handler *
+ACE_Sig_Handlers::handler (int signum)
+{
+  ACE_TRACE ("ACE_Sig_Handlers::handler");
+  ACE_SIG_HANDLERS_SET *handler_set =
+    ACE_Sig_Handlers_Set::instance (signum);
+  ACE_SIG_HANDLERS_ITERATOR handler_iterator (*handler_set);
+  ACE_Event_Handler **eh = 0;
+  handler_iterator.next (eh);
+  return *eh;
+}
+
+// The following is a strange bit of logic that tries to give the same
+// semantics as what happens in ACE_Sig_Handler when we replace the
+// current signal handler with a new one.  Note that if there is only
+// one signal handler the behavior will be identical.  If there is
+// more than one handler then things get weird...
+
+ACE_Event_Handler *
+ACE_Sig_Handlers::handler (int signum, ACE_Event_Handler *new_sh)
+{
+  ACE_TRACE ("ACE_Sig_Handlers::handler");
+  ACE_SIG_HANDLERS_SET *handler_set =
+    ACE_Sig_Handlers_Set::instance (signum);
+  ACE_SIG_HANDLERS_ITERATOR handler_iterator (*handler_set);
+  ACE_Event_Handler **eh = 0;
+
+  // Find the first handler...
+  handler_iterator.next (eh);
+
+  // ... then remove it from the set ...
+  handler_set->remove (*eh);
+
+  // ... and then insert the new signal handler into the beginning of
+  // the set (note, this is a bit too tied up in the implementation of
+  // ACE_Unbounded_Set...).
+  ACE_Sig_Adapter *temp = 0;
+
+  ACE_NEW_RETURN (temp,
+                  ACE_Sig_Adapter (new_sh,
+                                   ++ACE_Sig_Handlers::sigkey_),
+                  0);
+  handler_set->insert (temp);
+  return *eh;
+}
+
+ACE_END_VERSIONED_NAMESPACE_DECL