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author | Gregory Nutt <gnutt@nuttx.org> | 2013-10-20 11:37:56 -0600 |
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committer | Gregory Nutt <gnutt@nuttx.org> | 2013-10-20 11:37:56 -0600 |
commit | 5d38ee0f6f16a8db3b212d9282a21d5833b669e7 (patch) | |
tree | e97ba7461ff319ab77864afdf2aa45f0fcc340d9 /apps/examples/random/random_main.c | |
parent | cd6eaa5af6142c5a1027a14763df280b5c141999 (diff) | |
download | nuttx-5d38ee0f6f16a8db3b212d9282a21d5833b669e7.tar.gz nuttx-5d38ee0f6f16a8db3b212d9282a21d5833b669e7.tar.bz2 nuttx-5d38ee0f6f16a8db3b212d9282a21d5833b669e7.zip |
apps/examples/random: Add a test for /dev/random
Diffstat (limited to 'apps/examples/random/random_main.c')
-rw-r--r-- | apps/examples/random/random_main.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/apps/examples/random/random_main.c b/apps/examples/random/random_main.c new file mode 100644 index 000000000..ea8a3abc0 --- /dev/null +++ b/apps/examples/random/random_main.c @@ -0,0 +1,128 @@ +/**************************************************************************** + * examples/random/random_main.c + * + * Copyright (C) 2013 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 NuttX 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <fcntl.h> +#include <errno.h> +#include <debug.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ +/* Configuration ************************************************************/ + +#ifndef CONFIG_EXAMPLES_MAXSAMPLES +# define CONFIG_EXAMPLES_MAXSAMPLES 64 +#endif + +#ifndef CONFIG_EXAMPLES_NSAMPLES +# define CONFIG_EXAMPLES_NSAMPLES 8 +#endif + +#if CONFIG_EXAMPLES_NSAMPLES > CONFIG_EXAMPLES_MAXSAMPLES +# warning CONFIG_EXAMPLES_NSAMPLES > CONFIG_EXAMPLES_MAXSAMPLES +# undef CONFIG_EXAMPLES_NSAMPLES +# define CONFIG_EXAMPLES_NSAMPLES CONFIG_EXAMPLES_MAXSAMPLES +#endif + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * rand_main + ****************************************************************************/ + +int rand_main(int argc, char *argv[]) +{ + uint32_t buffer[CONFIG_EXAMPLES_MAXSAMPLES]; + int nsamples = CONFIG_EXAMPLES_NSAMPLES; + ssize_t nread; + int fd; + + /* One argument is possible... the number of samples to collect */ + + if (argc > 1) + { + nsamples = atoi(argv[1]); + } + + /* Clip the numer of samples to the configured buffer size */ + + if (nsamples > CONFIG_EXAMPLES_MAXSAMPLES) + { + nsamples = CONFIG_EXAMPLES_MAXSAMPLES; + } + + /* Open /dev/random */ + + fd = open("/dev/random", O_RDONLY); + if (fd < 0) + { + int errcode = errno; + fprintf(stderr, "ERROR: Failed to open /dev/random: %d\n", errcode); + exit(EXIT_FAILURE); + } + + /* Read the requested number of samples */ + + printf("Reading %d random numbers\n", nsamples); + nread = read(fd, buffer, nsamples * sizeof(uint32_t)); + if (nread < 0) + { + int errcode = errno; + fprintf(stderr, "ERROR: Read from /dev/randon failed: %d\n", errcode); + (void)close(fd); + exit(EXIT_FAILURE); + } + + /* Dump the sample buffer */ + + lib_dumpbuffer("Random values", (FAR const uint8_t*)buffer, nread); + (void)close(fd); + return EXIT_SUCCESS; +} + |