(svn r12706) -Merge: the thread rewrite from NoAI. The rewrite makes the threading we have better extendable.

1 files changed, 199 insertions, 0 deletions

diff --git a/src/thread_pthread.cpp b/src/thread_pthread.cpp
new file mode 100644
index 000000000..7aa0fda18
--- /dev/null
+++ b/src/thread_pthread.cpp
@@ -0,0 +1,199 @@
+/* $Id$ */
+
+/** @file thread_pthread.cpp POSIX pthread implementation of Threads. */
+
+#include "stdafx.h"
+#include "thread.h"
+#include "debug.h"
+#include "core/alloc_func.hpp"
+#include <stdlib.h>
+#include <pthread.h>
+#include <semaphore.h>
+#include <unistd.h>
+
+/**
+ * POSIX pthread version for ThreadObject.
+ */
+class ThreadObject_pthread : public ThreadObject {
+private:
+	pthread_t m_thr;             ///< System thread identifier.
+	OTTDThreadFunc m_proc;       ///< External thread procedure.
+	void     *m_param;           ///< Parameter for the external thread procedure.
+	bool      m_attached;        ///< True if the ThreadObject was attached to an existing thread.
+	sem_t     m_sem_start;       ///< Here the new thread waits before it starts.
+	sem_t     m_sem_stop;        ///< Here the other thread can wait for this thread to end.
+
+public:
+	/**
+	 * Create a pthread and start it, calling proc(param).
+	 */
+	ThreadObject_pthread(OTTDThreadFunc proc, void *param) :
+		m_thr(0),
+		m_proc(proc),
+		m_param(param),
+		m_attached(false)
+	{
+		sem_init(&m_sem_start, 0, 0);
+		sem_init(&m_sem_stop, 0, 0);
+
+		pthread_create(&m_thr, NULL, &stThreadProc, this);
+		sem_post(&m_sem_start);
+	}
+
+	/**
+	 * Create a pthread and attach current thread to it.
+	 */
+	ThreadObject_pthread() :
+		m_thr(0),
+		m_proc(NULL),
+		m_param(0),
+		m_attached(true)
+	{
+		sem_init(&m_sem_start, 0, 0);
+		sem_init(&m_sem_stop, 0, 0);
+
+		m_thr = pthread_self();
+	}
+
+	/* virtual */ ~ThreadObject_pthread()
+	{
+		sem_destroy(&m_sem_stop);
+		sem_destroy(&m_sem_start);
+	};
+
+	/* virtual */ bool IsRunning()
+	{
+		return m_thr != 0;
+	}
+
+	/* virtual */ bool WaitForStop()
+	{
+		/* You can't wait on yourself */
+		assert(!IsCurrent());
+		/* If the thread is not running, waiting is over */
+		if (!IsRunning()) return true;
+
+		int ret = sem_wait(&m_sem_stop);
+		if (ret == 0) {
+			/* We have passed semaphore so increment it again */
+			sem_post(&m_sem_stop);
+			return true;
+		}
+		return false;
+	}
+
+	/* virtual */ bool Exit()
+	{
+		/* You can only exit yourself */
+		assert(IsCurrent());
+		/* If the thread is not running, we are already closed */
+		if (!IsRunning()) return false;
+
+		/* For now we terminate by throwing an error, gives much cleaner cleanup */
+		throw 0;
+	}
+
+	/* virtual */ void *Join()
+	{
+		/* You cannot join yourself */
+		assert(!IsCurrent());
+
+		void *ret;
+		pthread_join(m_thr, &ret);
+		m_thr = 0;
+
+		return ret;
+	}
+
+	/* virtual */ bool IsCurrent()
+	{
+		return pthread_self() == m_thr;
+	}
+
+	/* virtual */ uint GetId()
+	{
+		return (uint)m_thr;
+	}
+
+private:
+	/**
+	 * On thread creation, this function is called, which calls the real startup
+	 *  function. This to get back into the correct instance again.
+	 */
+	static void *stThreadProc(void *thr)
+	{
+		return ((ThreadObject_pthread *)thr)->ThreadProc();
+	}
+
+	/**
+	 * A new thread is created, and this function is called. Call the custom
+	 *  function of the creator of the thread.
+	 */
+	void *ThreadProc()
+	{
+		/* The new thread stops here so the calling thread can complete pthread_create() call */
+		sem_wait(&m_sem_start);
+
+		/* Call the proc of the creator to continue this thread */
+		try {
+			m_proc(m_param);
+		} catch (...) {
+		}
+
+		/* Notify threads waiting for our completion */
+		sem_post(&m_sem_stop);
+
+		return NULL;
+	}
+};
+
+/* static */ ThreadObject *ThreadObject::New(OTTDThreadFunc proc, void *param)
+{
+	return new ThreadObject_pthread(proc, param);
+}
+
+/* static */ ThreadObject *ThreadObject::AttachCurrent()
+{
+	return new ThreadObject_pthread();
+}
+
+/* static */ uint ThreadObject::CurrentId()
+{
+	return (uint)pthread_self();
+}
+
+
+/**
+ * POSIX pthread version of ThreadSemaphore.
+ */
+class ThreadSemaphore_pthread : public ThreadSemaphore {
+private:
+	sem_t m_sem;
+
+public:
+	ThreadSemaphore_pthread()
+	{
+		sem_init(&m_sem, 0, 0);
+	}
+
+	/* virtual */ ~ThreadSemaphore_pthread()
+	{
+		sem_destroy(&m_sem);
+	}
+
+	/* virtual */ void Set()
+	{
+		int val = 0;
+		if (sem_getvalue(&m_sem, &val) == 0 && val == 0) sem_post(&m_sem);
+	}
+
+	/* virtual */ void Wait()
+	{
+		sem_wait(&m_sem);
+	}
+};
+
+/* static */ ThreadSemaphore *ThreadSemaphore::New()
+{
+	return new ThreadSemaphore_pthread();
+}