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Diffstat (limited to 'bin/tests/lfsr_test.c')
-rw-r--r-- | bin/tests/lfsr_test.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/bin/tests/lfsr_test.c b/bin/tests/lfsr_test.c new file mode 100644 index 0000000..4150b2d --- /dev/null +++ b/bin/tests/lfsr_test.c @@ -0,0 +1,95 @@ +/* + * Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 1999-2001 Internet Software Consortium. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH + * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + * PERFORMANCE OF THIS SOFTWARE. + */ + +/* $Id: lfsr_test.c,v 1.16 2007/06/19 23:46:59 tbox Exp $ */ + +/*! \file */ +#include <config.h> + +#include <stdio.h> + +#include <isc/lfsr.h> +#include <isc/util.h> + +isc_uint32_t state[1024 * 64]; + +int +main(int argc, char **argv) { + isc_lfsr_t lfsr1, lfsr2; + int i; + isc_uint32_t temp; + + UNUSED(argc); + UNUSED(argv); + + /* + * Verify that returned values are reproducable. + */ + isc_lfsr_init(&lfsr1, 0, 32, 0x80000057U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr1, &state[i], 4); + printf("lfsr1: state[%2d] = %08x\n", i, state[i]); + } + isc_lfsr_init(&lfsr1, 0, 32, 0x80000057U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr1, &temp, 4); + if (state[i] != temp) + printf("lfsr1: state[%2d] = %08x, " + "but new state is %08x\n", + i, state[i], temp); + } + + /* + * Now do the same with skipping. + */ + isc_lfsr_init(&lfsr1, 0, 32, 0x80000057U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr1, &state[i], 4); + isc_lfsr_skip(&lfsr1, 32); + printf("lfsr1: state[%2d] = %08x\n", i, state[i]); + } + isc_lfsr_init(&lfsr1, 0, 32, 0x80000057U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr1, &temp, 4); + isc_lfsr_skip(&lfsr1, 32); + if (state[i] != temp) + printf("lfsr1: state[%2d] = %08x, " + "but new state is %08x\n", + i, state[i], temp); + } + + /* + * Try to find the period of the LFSR. + * + * x^16 + x^5 + x^3 + x^2 + 1 + */ + isc_lfsr_init(&lfsr2, 0, 16, 0x00008016U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr2, &state[i], 4); + printf("lfsr2: state[%2d] = %08x\n", i, state[i]); + } + isc_lfsr_init(&lfsr2, 0, 16, 0x00008016U, 0, NULL, NULL); + for (i = 0; i < 32; i++) { + isc_lfsr_generate(&lfsr2, &temp, 4); + if (state[i] != temp) + printf("lfsr2: state[%2d] = %08x, " + "but new state is %08x\n", + i, state[i], temp); + } + + return (0); +} |