nuttx-apps/examples/random/random_main.c
Alin Jerpelea 2ac8589a25 examples: fix relative path CI error
error: Path relative to repository other than nuttx must begin with the root directory
Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-06-16 09:03:06 -05:00

131 lines
4.0 KiB
C

/****************************************************************************
* apps/examples/random/random_main.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.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 main(int argc, FAR 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 number of samples to the configured buffer size */
if (nsamples < 0)
{
nsamples = 0;
}
else if (nsamples > CONFIG_EXAMPLES_MAXSAMPLES)
{
nsamples = CONFIG_EXAMPLES_MAXSAMPLES;
}
/* fill buffer to make it super-clear as to what has and has not been written */
memset(buffer, 0xcc, sizeof(buffer));
/* 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);
fflush(stdout);
nread = read(fd, buffer, nsamples * sizeof(uint32_t));
if (nread < 0)
{
int errcode = errno;
fprintf(stderr, "ERROR: Read from /dev/random failed: %d\n", errcode);
close(fd);
exit(EXIT_FAILURE);
}
if (nread != nsamples * sizeof(uint32_t))
{
fprintf(stderr, "ERROR: Read from /dev/random only produced %d bytes\n",
(int)nread);
close(fd);
exit(EXIT_FAILURE);
}
/* Dump the sample buffer */
lib_dumpbuffer("Random values", (FAR const uint8_t*)buffer, nread);
close(fd);
return EXIT_SUCCESS;
}