ioctl.c

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <fcntl.h>
#include <getopt.h>
#include <string.h>
#ifdef __linux__
#include <linux/kd.h>
#include <linux/vt.h>
#endif
#include <errno.h>
#include <pthread.h>
#include <sys/ioctl.h>

int main(int argc, char *argv[]) {
	int fd;
	int res;

	int read_only = 0;
	int length = -1;
	int arg_size = 4;
	int direct_arg = 0;
	uint32_t ioctl_nr;
	void *ioctl_args;
	uint8_t *ioctl_argp;
	uint8_t *ioctl_argp_save;
	int rem;

	while(1) {
		int c = getopt(argc, argv, "rdl:a:h");
		if(c == EOF) break;
		switch(c) {
			case 'r':
				read_only = 1;
				break;
			case 'd':
				direct_arg = 1;
				break;
			case 'l':
				length = strtol(optarg, NULL, 0);
				break;
			case 'a':
				arg_size = strtol(optarg, NULL, 0);
				break;
			case 'h':
				fprintf(stderr, "Usage: %s [-l <length>] [-a <argsize>] [-rdh] <device> <ioctlnr>\n"
						"	-l <length>   Length of io buffer\n"
						"	-a <argsize>  Size of each argument (1-8)\n"
						"	-r            Open device in read only mode\n"
						"	-d            Direct argument (no iobuffer)\n"
						"	-h            Print help\n", argv[0]);
				return -1;
			case '?':
				fprintf(stderr, "%s: invalid option -%c\n", argv[0], optopt);
				exit(1);
		}
	}

	if(optind + 2 > argc) {
		fprintf(stderr, "%s: too few arguments\n", argv[0]);
		exit(1);
	}

	fd = open(argv[optind], (read_only ? O_RDWR : O_RDONLY) | O_SYNC);
	if(fd == -1) {
		fprintf(stderr, "cannot open %s\n", argv[optind]);
		return 1;
	}
	optind++;

	ioctl_nr = strtol(argv[optind], NULL, 0);
	optind++;

	if(direct_arg) {
		arg_size = 4;
		length = 4;
	}

	if(length < 0) {
		length = (argc - optind) * arg_size;
	}
	if(length) {
		ioctl_args = calloc(1, length);

		ioctl_argp_save = ioctl_argp = ioctl_args;
		rem = length;
		while(optind < argc) {
			uint64_t tmp = strtoull(argv[optind], NULL, 0);
			if(rem < arg_size) {
				fprintf(stderr, "%s: too many arguments\n", argv[0]);
				exit(1);
			}
			memcpy(ioctl_argp, &tmp, arg_size);
			ioctl_argp += arg_size;
			rem -= arg_size;
			optind++;
		}
	}
	printf("sending ioctl 0x%x", ioctl_nr);
	rem = length;
	while(rem--) {
		printf(" 0x%02x", *ioctl_argp_save++);
	}
	putchar('\n');

/*
	if(direct_arg) 
	   res = ioctl(fd, ioctl_nr, *(uint32_t *)ioctl_args);
	else if(length)
	   res = ioctl(fd, ioctl_nr, ioctl_args);
	else
	   res = ioctl(fd, ioctl_nr, 0);
*/
	//res = ioctl(fd, ioctl_nr, direct_arg ? *(uint32_t *)ioctl_args : (length ? ioctl_args : 0));

	if(direct_arg) res = ioctl(fd, ioctl_nr, *(uint32_t *)ioctl_args);
	else res = ioctl(fd, ioctl_nr, length ? ioctl_args : 0);
	if(res < 0) {
		fprintf(stderr, "ioctl 0x%x failed, %d\n", ioctl_nr, res);
		return 1;
	}
	if(length) {
		printf("return buf:");
		ioctl_argp = ioctl_args;
		rem = length;
		while(rem--) {
			printf(" %02x", *ioctl_argp++);
		}
		putchar('\n');
	}
	return 0;
}