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The netem directory contains code to generate tables for netem. This code came from NISTnet which was public domain. Add appropriate license tag. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
53 lines
991 B
C
53 lines
991 B
C
/* SPDX-License-Identifier: NIST-PD */
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/*
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* Normal distribution table generator
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* Taken from the uncopyrighted NISTnet code.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <math.h>
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#include <string.h>
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#include <limits.h>
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#include <linux/types.h>
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#include <linux/pkt_sched.h>
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#define TABLESIZE 16384
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#define TABLEFACTOR NETEM_DIST_SCALE
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static double
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normal(double x, double mu, double sigma)
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{
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return .5 + .5*erf((x-mu)/(sqrt(2.0)*sigma));
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}
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int
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main(int argc, char **argv)
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{
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int i, n;
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double x;
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double table[TABLESIZE+1];
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for (x = -10.0; x < 10.05; x += .00005) {
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i = rint(TABLESIZE * normal(x, 0.0, 1.0));
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table[i] = x;
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}
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printf("# This is the distribution table for the normal distribution.\n");
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for (i = n = 0; i < TABLESIZE; i += 4) {
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int value = (int) rint(table[i]*TABLEFACTOR);
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if (value < SHRT_MIN) value = SHRT_MIN;
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if (value > SHRT_MAX) value = SHRT_MAX;
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printf(" %d", value);
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if (++n == 8) {
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putchar('\n');
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n = 0;
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}
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}
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return 0;
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}
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