Merged master into safelinksafelink

1 files changed, 82 insertions, 0 deletions

diff --git a/src/modules/systemlib/state_table.h b/src/modules/systemlib/state_table.h
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+++ b/src/modules/systemlib/state_table.h
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+/****************************************************************************
+ *
+ *   Copyright (C) 2013-2014 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file state_table.h
+ *
+ * Finite-State-Machine helper class for state table
+ * @author: Julian Oes <julian@oes.ch>
+ */
+
+#ifndef __SYSTEMLIB_STATE_TABLE_H
+#define __SYSTEMLIB_STATE_TABLE_H
+
+class StateTable
+{
+public:
+	typedef void (StateTable::*Action)();
+	struct Tran {
+		Action action;
+		unsigned nextState;
+	};
+
+	StateTable(Tran const *table, unsigned nStates, unsigned nSignals)
+	: myTable(table), myNsignals(nSignals), myNstates(nStates) {}
+
+	#define NO_ACTION &StateTable::doNothing
+	#define ACTION(_target) StateTable::Action(_target)
+
+	virtual ~StateTable() {}
+
+	void dispatch(unsigned const sig) {
+		/* get transition using state table */
+		Tran const *t = myTable + myState*myNsignals + sig;
+
+		/* accept new state */
+		myState = t->nextState;
+
+		/*  */
+		(this->*(t->action))();
+	}
+	void doNothing() {
+		return;
+	}
+protected:
+	unsigned myState;
+private:
+	Tran const *myTable;
+	unsigned myNsignals;
+	unsigned myNstates;
+};
+
+#endif