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/*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*/
/*
* Copyright 2022 Oxide Computer Company
*/
/*
* This is designed to allow us to execute print() and various dereferencing
* operations with bitfields. It reads the values from argc and passes them to
* functions that we can then take apart. Crtitically this uses bitfields
* constructed via CTF and not the D compiler.
*/
#include <err.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdlib.h>
#include <errno.h>
typedef struct bit0 {
uint32_t a:3;
uint32_t b:2;
uint32_t c:1;
uint32_t d:1;
uint32_t e:1;
uint32_t f:1;
uint32_t g:3;
uint32_t h:3;
uint32_t i:5;
uint32_t j:4;
uint32_t k:6;
uint32_t l:1;
uint32_t m:1;
} bit0_t;
typedef struct bit1 {
uint16_t a:1;
uint16_t b:8;
uint16_t c:3;
uint16_t d:2;
uint16_t e:1;
uint16_t f:1;
} bit1_t;
void
mumble(FILE *f, bit0_t *zero, bit1_t *one)
{
(void) fprintf(f, "%u\n%u\n", zero->k, one->d);
}
int
main(int argc, char *argv[])
{
unsigned long l;
uint16_t u16;
uint32_t u32;
FILE *f;
if (argc != 3) {
errx(EXIT_FAILURE, "Need two ints");
}
f = fopen("/dev/null", "rw+");
if (f == NULL) {
err(EXIT_FAILURE, "failed to open /dev/null");
}
errno = 0;
l = strtoul(argv[1], NULL, 0);
if (errno != 0 || l == 0 || l > UINT16_MAX) {
errx(EXIT_FAILURE, "invalid u16 value: %s", argv[1]);
}
u16 = (uint16_t)l;
l = strtoul(argv[2], NULL, 0);
if (errno != 0 || l == 0 || l > UINT32_MAX) {
errx(EXIT_FAILURE, "invalid u32 value: %s", argv[1]);
}
u32 = (uint32_t)l;
mumble(f, (bit0_t *)&u32, (bit1_t *)&u16);
return (0);
}
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