--- /dev/null
+/*
+ * Copyright (c) 2003-2005 The BISON Project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+package peersim.core;
+
+import org.simgrid.msg.Msg;
+
+import peersim.Simulator;
+import peersim.config.*;
+import peersim.util.*;
+import psgsim.PSGPlatform;
+
+/**
+ * This is the common state of the simulation all objects see.
+ * Static singleton. One of its purposes is
+ * simplification of parameter structures and increasing efficiency by putting
+ * state information here instead of passing parameters.
+ *<p>
+ * <em>The set methods should not be used by applications</em>,
+ * they are for system
+ * components. Use them only if you know exactly what you are doing, e.g.
+ * if you are so advanced that you can write your own simulation engine.
+ * Ideally, they should not be visible, but due to the lack of more
+ * flexibility in java access rights, we are forced to make them public.
+ */
+public class CommonState
+{
+
+//======================= constants ===============================
+//=================================================================
+
+/**
+* Constant that can be used as a value of simulation phase.
+* It means that the simulation has finished.
+* @see #getPhase
+*/
+public static final int POST_SIMULATION = 1;
+
+/**
+* Constant that can be used as a value of simulation phase.
+* It means that the simulation phase information has not been set (unknown).
+* @see #getPhase
+*/
+public static final int PHASE_UNKNOWN = 0;
+
+// ======================= fields ==================================
+// =================================================================
+
+/**
+ * Current time. Note that this value is simulator independent, all simulation
+ * models have a notion related to time. For example, in the cycle based model,
+ * the cycle id gives time, while in even driven simulations there is a more
+ * realistic notion of time.
+ */
+private static long time = 0;
+
+/**
+ * The maximal value {@link #time} can ever take.
+ */
+private static long endtime = -1;
+
+/**
+ * Number of used bits in the long representation of time, calculated
+ * based on the endtime.
+ */
+private static int toshift = -1;
+
+/**
+ * Information about where exactly the simulation is.
+ */
+private static int phase = PHASE_UNKNOWN;
+
+/**
+ * The current pid.
+ */
+private static int pid;
+
+/**
+ * The current node.
+ */
+private static Node node;
+
+/**
+* This source of randomness should be used by all components.
+* This field is public because it doesn't matter if it changes
+* during an experiment (although it shouldn't) until no other sources of
+* randomness are used within the system. Besides, we can save the cost
+* of calling a wrapper method, which is important because this is needed
+* very often.
+*/
+public static ExtendedRandom r = null;
+
+
+// ======================== initialization =========================
+// =================================================================
+
+/**
+* Configuration parameter used to define which random generator
+* class should be used. If not specified, the default implementation
+* {@link ExtendedRandom} is used. User-specified random generators
+* must extend class {@link ExtendedRandom}.
+* @config
+*/
+public static final String PAR_RANDOM = "random";
+
+/**
+* Configuration parameter used to initialize the random seed.
+* If it is not specified the current time is used.
+* @config
+*/
+public static final String PAR_SEED = "random.seed";
+
+
+/**
+* Initializes the field {@link r} according to the configuration.
+* Assumes that the configuration is already
+* loaded.
+*/
+static {
+
+ long seed =
+ Configuration.getLong(PAR_SEED,System.currentTimeMillis());
+ initializeRandom(seed);
+}
+
+
+/** Does nothing. To avoid construction but allow extension. */
+protected CommonState() {}
+
+// ======================= methods =================================
+// =================================================================
+
+
+/**
+ * Returns current time. In event-driven simulations, returns the current
+ * time (a long-value).
+ * In cycle-driven simulations, returns the current cycle (a long that
+ * can safely be cast into an integer).
+ */
+public static long getTime()
+{
+ /* if the engine simulator used is PSG (simId=2 */
+ if(Simulator.getSimID()==2)
+ return (long) PSGPlatform.getTime();
+ else
+ return time;
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Returns current time in integer format. The purpose is to enhance the
+ * performance of protocols (ints are smaller and faster) when absolute
+ * precision is not required. It assumes that endtime has been set via
+ * {@link #setEndTime} by the simulation engine. It uses the endtime for
+ * the optimal mapping to get the maximal precision.
+ * In particular, in the cycle
+ * based model, time is the same as cycle which can be safely cast into
+ * integer, so no precision is lost.
+ */
+public static int getIntTime()
+{
+ return (int)(time>>toshift);
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Sets the current time.
+ */
+public static void setTime(long t)
+{
+ time = t;
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Returns endtime.
+ * It is the maximal value {@link #getTime} ever returns. If it's negative, it
+ * means the endtime is not known.
+ */
+public static long getEndTime()
+{
+ return endtime;
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Sets the endtime.
+ */
+public static void setEndTime(long t)
+{
+ if( endtime >= 0 )
+ throw new RuntimeException("You can set endtime only once");
+ if( t < 0 )
+ throw new RuntimeException("No negative values are allowed");
+
+ endtime = t;
+ toshift = 32-Long.numberOfLeadingZeros(t);
+ if( toshift<0 ) toshift = 0;
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Returns the simulation phase. Currently the following phases are
+ * understood.
+ * <ul>
+ * <li>{@link #PHASE_UNKNOWN} phase is unknown</li>
+ * <li>{@link #POST_SIMULATION} the simulation is completed</li>
+ * </ul>
+ */
+public static int getPhase()
+{
+ return phase;
+}
+
+// -----------------------------------------------------------------
+
+public static void setPhase(int p)
+{
+ phase = p;
+}
+
+// -----------------------------------------------------------------
+
+/**
+* Returns the current protocol identifier. In other words, control is
+* held by the indicated protocol on node {@link #getNode}.
+*/
+public static int getPid()
+{
+ return pid;
+}
+
+//-----------------------------------------------------------------
+
+/** Sets the current protocol identifier.*/
+public static void setPid(int p)
+{
+ pid = p;
+}
+
+//-----------------------------------------------------------------
+
+/**
+ * Returns the current node. When a protocol is executing, it is the node
+ * hosting the protocol.
+ */
+public static Node getNode()
+{
+ return node;
+}
+
+//-----------------------------------------------------------------
+
+/** Sets the current node */
+public static void setNode(Node n)
+{
+ node = n;
+}
+
+//-----------------------------------------------------------------
+
+public static void initializeRandom(long seed)
+{
+ if (r == null) {
+ r = (ExtendedRandom) Configuration.getInstance(PAR_RANDOM, new ExtendedRandom(seed));
+ }
+ r.setSeed(seed);
+}
+
+//-----------------------------------------------------------------
+
+/*
+public static void main(String pars[]) {
+
+ setEndTime(Long.parseLong(pars[0]));
+ setTime(Long.parseLong(pars[1]));
+ System.err.println(getTime()+" "+getIntTime());
+}
+*/
+}
+
