Fix threading test.

Add threading demo from 2.0, with minor improvements to make the
prime number generation faster/more realistic.


git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@1823 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 164 insertions, 0 deletions

diff --git a/test/threads.h b/test/threads.h
new file mode 100644
index 000000000..2f3a81d1e
--- /dev/null
+++ b/test/threads.h
@@ -0,0 +1,164 @@
+//
+// "$Id: threads.h,v 1.1.2.1 2001/12/08 16:23:51 easysw Exp $"
+//
+// Simple threading API for the Fast Light Tool Kit (FLTK).
+//
+// Copyright 1998-2001 by Bill Spitzak and others.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems to "fltk-bugs@fltk.org".
+//
+
+// Inline classes to provide portable support for threads and mutexes.
+//
+// FLTK does not use this (it has an internal mutex implementation
+// that is used if Fl::lock() is called). This header file's only
+// purpose is so we can write portable demo programs. It may be useful
+// or an inspiration to people who want to try writing multithreaded
+// programs themselves.
+//
+// FLTK has no multithreaded support unless the main thread calls Fl::lock().
+// This main thread is the only thread allowed to call Fl::run() or Fl::wait().
+// From then on FLTK will be locked except when the main thread is actually
+// waiting for events from the user. Other threads must call Fl::lock() and
+// Fl::unlock() to surround calls to FLTK (such as to change widgets or
+// redraw them).
+
+#ifndef Threads_H
+#  define Threads_H
+
+#  ifndef WIN32
+// Use POSIX threading...
+
+#    include <pthread.h>
+
+typedef pthread_t Fl_Thread;
+
+static int fl_create_thread(Fl_Thread& t, void *(*f) (void *), void* p)
+{
+  return pthread_create((pthread_t*)&t, 0, f, p);
+}
+
+// Linux supports recursive locks, use them directly, with some cheating:
+#    ifdef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+
+extern pthread_mutexattr_t Fl_Mutex_attrib;
+
+class Fl_Mutex {
+  friend class Fl_SignalMutex;
+  pthread_mutex_t mutex;
+  Fl_Mutex(const Fl_Mutex&);
+  Fl_Mutex& operator=(const Fl_Mutex&);
+public:
+  Fl_Mutex() {pthread_mutex_init(&mutex, &Fl_Mutex_attrib);}
+  void lock() {pthread_mutex_lock(&mutex);}
+  void unlock() {pthread_mutex_unlock(&mutex);}
+  ~Fl_Mutex() {pthread_mutex_destroy(&mutex);}
+};
+
+class Fl_SignalMutex : public Fl_Mutex {
+  pthread_cond_t cond;
+public:
+  Fl_SignalMutex() : Fl_Mutex() {pthread_cond_init(&cond, 0);}
+  void signal() {pthread_cond_broadcast(&cond);}
+  void wait() {
+    int save_counter = mutex.m_count; mutex.m_count = 1;
+    pthread_cond_wait(&cond, &mutex);
+    mutex.m_count = save_counter;
+  }
+};
+
+#    else // standard pthread mutexes need a bit of work to be recursive:
+
+class Fl_Mutex {
+  friend class Fl_SignalMutex;
+  pthread_mutex_t mutex;
+  pthread_t owner;
+  int counter;
+  Fl_Mutex(const Fl_Mutex&);
+  Fl_Mutex& operator=(const Fl_Mutex&);
+public:
+  Fl_Mutex() : counter(0) {pthread_mutex_init(&mutex, 0);}
+  void lock() {
+    if (!counter || owner != pthread_self()) {
+      pthread_mutex_lock(&mutex); owner = pthread_self();
+    }
+    counter++;
+  }
+  void unlock() {if (!--counter) pthread_mutex_unlock(&mutex);}
+  ~Fl_Mutex() {pthread_mutex_destroy(&mutex);}
+};
+
+class Fl_SignalMutex : public Fl_Mutex {
+  pthread_cond_t cond;
+public:
+  Fl_SignalMutex() : Fl_Mutex() {pthread_cond_init(&cond, 0);}
+  void signal() {pthread_cond_broadcast(&cond);}
+  void wait() {
+    int save_counter = counter; counter = 0;
+    pthread_cond_wait(&cond, &mutex);
+    counter = save_counter;
+    owner = pthread_self();
+  }
+};
+
+#    endif
+
+#  else // Use Windows threading...
+
+#    include <windows.h>
+#    include <process.h>
+
+typedef unsigned long Fl_Thread;
+
+static int fl_create_thread(Fl_Thread& t, void *(*f) (void *), void* p) {
+  return t = (Fl_Thread)_beginthread((void( __cdecl * )( void * ))f, 0, p);
+}
+
+class FL_API Fl_Mutex {
+  friend class Fl_SignalMutex;
+  CRITICAL_SECTION cs;
+  Fl_Mutex(const Fl_Mutex&);
+  Fl_Mutex& operator=(const Fl_Mutex&);
+public:
+  Fl_Mutex() {InitializeCriticalSection(&cs);}
+  void lock() {EnterCriticalSection(&cs);}
+  void unlock() {LeaveCriticalSection(&cs);}
+  ~Fl_Mutex() {DeleteCriticalSection(&cs);}
+};
+
+class FL_API Fl_SignalMutex : public Fl_Mutex {
+  HANDLE event;
+public:
+  Fl_SignalMutex() : Fl_Mutex() {event = CreateEvent(0, FALSE, FALSE, 0);}
+  void signal() {SetEvent(event);}
+  void wait() {
+    // int save_counter = cs.count; cs.count = 1;
+    // the following three calls should be atomic, sigh...
+    LeaveCriticalSection(&cs);
+    WaitForSingleObject(event, INFINITE);
+    EnterCriticalSection(&cs);
+    // cs.count = save_counter;
+  }
+};
+
+#  endif // !WIN32
+#endif // !Threads_h
+
+//
+// End of "$Id: threads.h,v 1.1.2.1 2001/12/08 16:23:51 easysw Exp $".
+//