setdest2.cc

Go to the documentation of this file.

/*
 * a simplified version of setdest which bypass the computation of route length.
 */

extern "C" {
#include <assert.h>
#include <fcntl.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#if !defined(sun) && !defined(__CYGWIN__)
#include <err.h>
#endif
};
#include "../../../rng.h"

#include "setdest.h"


// #define      DEBUG
#define     SANITY_CHECKS
//#define       SHOW_SYMMETRIC_PAIRS


#define GOD_FORMAT  "$ns_ at %.12f \"$god_ set-dist %d %d %d\"\n"
#define GOD_FORMAT2 "$god_ set-dist %d %d %d\n"
#define NODE_FORMAT "$ns_ at %.12f \"$node_(%d) setdest %.12f %.12f %.12f\"\n"
#define NODE_FORMAT2    "$node_(%d) setdest %.12f %.12f %.12f\n"
#define NODE_FORMAT3    "$node_(%d) set %c_ %.12f\n"

#define     INFINITY    0x00ffffff
#define     min(x,y)    ((x) < (y) ? (x) : (y))
#define     max(x,y)    ((x) > (y) ? (x) : (y))
#define     ROUND_ERROR 1e-9

static int count = 0;

/* ======================================================================
   Function Prototypes
   ====================================================================== */
void        usage(char**);
void        init(void);
double      uniform(void);

void        dumpall(void);
void        ComputeW(void);
void        floyd_warshall(void);

void        show_diffs(void);
void        show_routes(void);
void        show_counters(void);


/* ======================================================================
   Global Variables
   ====================================================================== */
const double    RANGE = 250.0;      // transmitter range in meters
double      TIME = 0.0;     // my clock;
double      MAXTIME = 0.0;      // duration of simulation

double      MAXX = 0.0;
double      MAXY = 0.0;
double      MAXSPEED = 0.0;
double      PAUSE = 0.0;
u_int32_t   NODES = 0;
u_int32_t   RouteChangeCount = 0;
u_int32_t       LinkChangeCount = 0;
u_int32_t   DestUnreachableCount = 0;

Node        *NodeList = 0;
u_int32_t   *D1 = 0;
u_int32_t   *D2 = 0;


/* ======================================================================
   Random Number Generation
   ====================================================================== */
#define M       2147483647L
#define INVERSE_M   ((double)4.656612875e-10)

char random_state[32];
RNG *rng;

double
uniform()
{
        count++;
        return rng->uniform_double() ;
} 


/* ======================================================================
   Misc Functions...
   ====================================================================== */
void
usage(char **argv)
{
    fprintf(stderr,
        "\nusage: %s\t-n <nodes> -p <pause time> -s <max speed>\n",
        argv[0]);
    fprintf(stderr,
        "\t\t-t <simulation time> -x <max X> -y <max Y>\n\n");
}

void
init()
{
    /*
     * Initialized the Random Number Generation
     */
"
    /*"
     * Allocate memory for globals
     */
    NodeList = new Node[NODES];
    if(NodeList == 0) {
        perror("new");
        exit(1);
    }

    D1 = new u_int32_t[NODES * NODES];
    if(D1 == 0) {
        perror("new");
        exit(1);
    }
    memset(D1, '\xff', sizeof(u_int32_t) * NODES * NODES);

    D2 = new u_int32_t[NODES * NODES];
    if(D2 == 0) {
        perror("new");
        exit(1);
    }
    memset(D2, '\xff', sizeof(u_int32_t) * NODES * NODES);
}

extern "C" char *optarg;

int
main(int argc, char **argv)
{
    char ch;

    while ((ch = getopt(argc, argv, "n:p:s:t:x:y:i:o:")) != EOF) {       

        switch (ch) { 

        case 'n':
            NODES = atoi(optarg);
            break;

        case 'p':
            PAUSE = atof(optarg);
            break;

        case 's':
            MAXSPEED = atof(optarg);
            break;

        case 't':
            MAXTIME = atof(optarg);
            break;

        case 'x':
            MAXX = atof(optarg);
            break;

        case 'y':
            MAXY = atof(optarg);
            break;

        default:
            usage(argv);
            exit(1);
        }
    }

    if(MAXX == 0.0 || MAXY == 0.0 || NODES == 0 || MAXTIME == 0.0) {
        usage(argv);
        exit(1);
    }

    fprintf(stdout, "#\n# nodes: %d, pause: %.2f, max speed: %.2f  max x = %.2f, max y: %.2f\n#\n",
        NODES , PAUSE, MAXSPEED, MAXX, MAXY);

    // The more portable solution for random number generation
    rng = new RNG;
    rng->set_seed(RNG::HEURISTIC_SEED_SOURCE); 

    init();

    while(TIME <= MAXTIME) {
        double nexttime = 0.0;
        u_int32_t i;

        for(i = 0; i < NODES; i++) {
            NodeList[i].Update();
        }
/*
        for(i = 0; i < NODES; i++) {
            NodeList[i].UpdateNeighbors();
        }
*/
        for(i = 0; i < NODES; i++) {
            Node *n = &NodeList[i];
    
            if(n->time_transition > 0.0) {
                if(nexttime == 0.0)
                    nexttime = n->time_transition;
                else
                    nexttime = min(nexttime, n->time_transition);
            }

            if(n->time_arrival > 0.0) {
                if(nexttime == 0.0)
                    nexttime = n->time_arrival;
                else
                    nexttime = min(nexttime, n->time_arrival);
            }
        }

        // floyd_warshall();

#ifdef DEBUG
        show_routes();
#endif

        // show_diffs();

#ifdef DEBUG
        dumpall();
#endif

        assert(nexttime > TIME + ROUND_ERROR);
        TIME = nexttime;
    }

    show_counters();

    int of;
    if ((of = open(".rand_state",O_WRONLY | O_TRUNC | O_CREAT, 0777)) < 0) {
      fprintf(stderr, "open rand state\n");
      exit(-1);
      }
    for (unsigned int i = 0; i < sizeof(random_state); i++)
          random_state[i] = 0xff & (int) (uniform() * 256);
    if (write(of,random_state, sizeof(random_state)) < 0) {
      fprintf(stderr, "writing rand state\n");
      exit(-1);
      }
    close(of);
}


/* ======================================================================
   Node Class Functions
   ====================================================================== */
u_int32_t Node::NodeIndex = 0;

Node::Node()
{
    u_int32_t i;

    index = NodeIndex++;

    //if(index == 0)
    //  return;

    route_changes = 0;
        link_changes = 0;

        /*
         * For the first PAUSE seconds of the simulation, all nodes
         * are stationary.
         */
    time_arrival = TIME + PAUSE;
    time_update = TIME;
    time_transition = 0.0;

    position.X = position.Y = position.Z = 0.0;
    destination.X = destination.Y = destination.Z = 0.0;
    direction.X = direction.Y = direction.Z = 0.0;
    speed = 0.0;

    RandomPosition();

    fprintf(stdout, NODE_FORMAT3, index, 'X', position.X);
    fprintf(stdout, NODE_FORMAT3, index, 'Y', position.Y);
    fprintf(stdout, NODE_FORMAT3, index, 'Z', position.Z);

    neighbor = new Neighbor[NODES];
    if(neighbor == 0) {
        perror("new");
        exit(1);
    }

    for(i = 0; i < NODES; i++) {
        neighbor[i].index = i;
        neighbor[i].reachable = (index == i) ? 1 : 0;
        neighbor[i].time_transition = 0.0;
    }
}



void
Node::RandomPosition()
{
        position.X = uniform() * MAXX;
        position.Y = uniform() * MAXY;
    position.Z = 0.0;
}


void
Node::RandomDestination()
{
        destination.X = uniform() * MAXX;
        destination.Y = uniform() * MAXY;
    destination.Z = 0.0;
    assert(destination != position);
}

void
Node::RandomSpeed()
{
        speed = uniform() * MAXSPEED;

    assert(speed != 0.0);
}


void
Node::Update()
{
    position += (speed * (TIME - time_update)) * direction;

    if(TIME == time_arrival) {
        vector v;

        if(speed == 0.0 || PAUSE == 0.0) {

                        RandomDestination();
            RandomSpeed();

            v = destination - position;
            direction = v / v.length();
            time_arrival = TIME + v.length() / speed;
        }
        else {

            destination = position;
            speed = 0.0;

            time_arrival = TIME + PAUSE;
        }

        fprintf(stdout, NODE_FORMAT,
            TIME, index, destination.X, destination.Y, speed);
    
    }

    time_update = TIME;
    time_transition = 0.0;
}


void
Node::UpdateNeighbors()
{
    static Node *n2;
    static Neighbor *m1, *m2;
    static vector D, B, v1, v2;
    static double a, b, c, t1, t2, Q;
    static u_int32_t i, reachable;

    v1 = speed * direction;

    /*
     *  Only need to go from INDEX --> N for each one since links
     *  are symmetric.
     */
    for(i = index+1; i < NODES; i++) {

        m1 = &neighbor[i];
        n2 = &NodeList[i];
        m2 = &n2->neighbor[index];

        assert(i == m1->index);
        assert(m1->index == n2->index);
        assert(index == m2->index);
                assert(m1->reachable == m2->reachable);

                reachable = m1->reachable;

        /* ==================================================
           Determine Reachability
           ================================================== */
        {   vector d = position - n2->position;

            if(d.length() < RANGE) {
#ifdef SANITY_CHECKS
                if(TIME > 0.0 && m1->reachable == 0)
                    assert(RANGE - d.length() < ROUND_ERROR);
#endif
                m1->reachable = m2->reachable = 1;
            }
            // Boundary condition handled below.
            else {
#ifdef SANITY_CHECKS
                if(TIME > 0.0 && m1->reachable == 1)
                    assert(d.length() - RANGE < ROUND_ERROR);
#endif
                m1->reachable = m2->reachable = 0;
            }
#ifdef DEBUG
                        fprintf(stdout, "# %.6f (%d, %d) %.2fm\n",
                                TIME, index, m1->index, d.length());
#endif
        }

        /* ==================================================
           Determine Next Event Time
           ================================================== */
        v2 = n2->speed * n2->direction;

        D = v2 - v1;
        B = n2->position - position;

        a = (D.X * D.X) + (D.Y * D.Y) + (D.Z * D.Z);
        b = 2 * ((D.X * B.X) + (D.Y * B.Y) + (D.Z * B.Z));
        c = (B.X * B.X) + (B.Y * B.Y) + (B.Z * B.Z) - (RANGE * RANGE);

        if(a == 0.0) {
            /*
             *  No Finite Solution
             */
            m1->time_transition= 0.0;
            m2->time_transition= 0.0;
            goto  next;
        }

        Q = b * b - 4 * a * c;
        if(Q < 0.0) {
            /*
             *  No real roots.
             */
            m1->time_transition = 0.0;
            m2->time_transition = 0.0;
            goto next;
        }
        Q = sqrt(Q);

        t1 = (-b + Q) / (2 * a);
        t2 = (-b - Q) / (2 * a);

        // Stupid Rounding/Boundary Cases
        if(t1 > 0.0 && t1 < ROUND_ERROR) t1 = 0.0;
        if(t1 < 0.0 && -t1 < ROUND_ERROR) t1 = 0.0;
        if(t2 > 0.0 && t2 < ROUND_ERROR) t2 = 0.0;
        if(t2 < 0.0 && -t2 < ROUND_ERROR) t2 = 0.0;

        if(t1 < 0.0 && t2 < 0.0) {
            /*
             *  No "future" time solution.
             */
            m1->time_transition = 0.0;
            m2->time_transition = 0.0;
            goto next;
        }

        /*
         * Boundary conditions.
         */
        if((t1 == 0.0 && t2 > 0.0) || (t2 == 0.0 && t1 > 0.0)) {
            m1->reachable = m2->reachable = 1;
            m1->time_transition = m2->time_transition = TIME + max(t1, t2);
        }
        else if((t1 == 0.0 && t2 < 0.0) || (t2 == 0.0 && t1 < 0.0)) {
            m1->reachable = m2->reachable = 0;
            m1->time_transition = m2->time_transition = 0.0;
        }

        /*
         * Non-boundary conditions.
         */
        else if(t1 > 0.0 && t2 > 0.0) {
            m1->time_transition = TIME + min(t1, t2);
            m2->time_transition = TIME + min(t1, t2);
        }
        else if(t1 > 0.0) {
            m1->time_transition = TIME + t1;
            m2->time_transition = TIME + t1;
        }
        else {
            m1->time_transition = TIME + t2;
            m2->time_transition = TIME + t2;
        }

        /* ==================================================
           Update the transition times for both NODEs.
           ================================================== */
        if(time_transition == 0.0 || (m1->time_transition &&
           time_transition > m1->time_transition)) {
            time_transition = m1->time_transition;
        }
        if(n2->time_transition == 0.0 || (m2->time_transition &&
           n2->time_transition > m2->time_transition)) {
            n2->time_transition = m2->time_transition;
        }
        next:
                if(reachable != m1->reachable && TIME > 0.0) {
                        LinkChangeCount++;
                        link_changes++;
                        n2->link_changes++;
                }
    }
}

void
Node::Dump()
{
    Neighbor *m;
    u_int32_t i;

    fprintf(stdout,
        "Node: %d\tpos: (%.2f, %.2f, %.2f) dst: (%.2f, %.2f, %.2f)\n",
        index, position.X, position.Y, position.Z,
        destination.X, destination.Y, destination.Z);
    fprintf(stdout, "\tdir: (%.2f, %.2f, %.2f) speed: %.2f\n",
        direction.X, direction.Y, direction.Z, speed);
    fprintf(stdout, "\tArrival: %.2f, Update: %.2f, Transition: %.2f\n",
        time_arrival, time_update, time_transition);

    for(i = 0; i < NODES; i++) {
        m = &neighbor[i];
        fprintf(stdout, "\tNeighbor: %d (%x), Reachable: %d, Transition Time: %.2f\n",
            m->index, (int) m, m->reachable, m->time_transition);
    }
}


/* ======================================================================
   Dijkstra's Shortest Path Algoritm
   ====================================================================== */
void dumpall()
{
    u_int32_t i;

    fprintf(stdout, "\nTime: %.2f\n", TIME);

    for(i = 0; i < NODES; i++) {
        NodeList[i].Dump();
    }
}

void
ComputeW()
{
    u_int32_t i, j;
    u_int32_t *W = D2;

    memset(W, '\xff', sizeof(int) * NODES * NODES);

    for(i = 0; i < NODES; i++) {
        for(j = i; j < NODES; j++) {
            Neighbor *m = &NodeList[i].neighbor[j];
            if(i == j)
                W[i*NODES + j] = W[j*NODES + i] = 0;
            else
                W[i*NODES + j] = W[j*NODES + i] = m->reachable ? 1 : INFINITY;  
        }
    }
}

void
floyd_warshall()
{
    u_int32_t i, j, k;

    ComputeW(); // the connectivity matrix

    for(i = 0; i < NODES; i++) {
        for(j = 0; j < NODES; j++) {
            for(k = 0; k < NODES; k++) {
                D2[j*NODES + k] = min(D2[j*NODES + k], D2[j*NODES + i] + D2[i*NODES + k]);
            }
        }
    }

#ifdef SANITY_CHECKS
    for(i = 0; i < NODES; i++)
        for(j = 0; j < NODES; j++) {
            assert(D2[i*NODES + j] == D2[j*NODES + i]);
            assert(D2[i*NODES + j] <= INFINITY);
        }
#endif
}


/*
 *  Write the actual GOD entries to a TCL script.
 */
void
show_diffs()
{
    u_int32_t i, j;

    for(i = 0; i < NODES; i++) {
        for(j = i + 1; j < NODES; j++) {
            if(D1[i*NODES + j] != D2[i*NODES + j]) {

                if(D2[i*NODES + j] == INFINITY)
                    DestUnreachableCount++;

                                if(TIME > 0.0) {
                                        RouteChangeCount++;
                                        NodeList[i].route_changes++;
                                        NodeList[j].route_changes++;
                                }

                if(TIME == 0.0) {
                    fprintf(stdout, GOD_FORMAT2,
                        i, j, D2[i*NODES + j]);
#ifdef SHOW_SYMMETRIC_PAIRS
                    fprintf(stdout, GOD_FORMAT2,
                        j, i, D2[j*NODES + i]);
#endif
                }
                else {
                    fprintf(stdout, GOD_FORMAT, 
                        TIME, i, j, D2[i*NODES + j]);
#ifdef SHOW_SYMMETRIC_PAIRS
                    fprintf(stdout, GOD_FORMAT, 
                        TIME, j, i, D2[j*NODES + i]);
#endif
                }
            }
        }
    }

    memcpy(D1, D2, sizeof(int) * NODES * NODES);
}


void
show_routes()
{
    u_int32_t i, j;

    fprintf(stdout, "#\n# TIME: %.12f\n#\n", TIME);
    for(i = 0; i < NODES; i++) {
        fprintf(stdout, "# %2d) ", i);
        for(j = 0; j < NODES; j++)
            fprintf(stdout, "%3d ", D2[i*NODES + j] & 0xff);
        fprintf(stdout, "\n");
    }
    fprintf(stdout, "#\n");
}

void
show_counters()
{
    u_int32_t i;

    fprintf(stdout, "#\n# Destination Unreachables: %d\n#\n",
        DestUnreachableCount);
    fprintf(stdout, "# Route Changes: %d\n#\n", RouteChangeCount);
        fprintf(stdout, "# Link Changes: %d\n#\n", LinkChangeCount);
        fprintf(stdout, "# Node | Route Changes | Link Changes\n");
    for(i = 0; i < NODES; i++)
        fprintf(stdout, "# %4d |          %4d |         %4d\n",
                        i, NodeList[i].route_changes,
                        NodeList[i].link_changes);
    fprintf(stdout, "#\n");
}

---