test.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>

struct dev_orientation {
	int azimuth;	/* angle between the magnetic north and the Y axis,
			   around the Z axis (0 <= azimuth < 360)
			   0 = north, 90 = east, 180 = south, 270 = west */
	int pitch;	/* rotation around the X-axis: -180 <= pitch <= 180 */
	int roll;	/* rotation around the Y-axis: +Y == -roll,
			   -90 <= roll <= 90 */
};

struct orientation_range {
	struct dev_orientation orient;	/* device orientation */
	unsigned int azimuth_range;	/* +/- degrees around Z axis */
	unsigned int pitch_range;	/* +/- degrees around X axis */
	unsigned int roll_range;	/* +/- degrees around Y axis */
};

/* The orientation range to set. */
struct orientation_range range = {
        .orient = {
                .azimuth = 50,
                .pitch = 30,
                .roll = 25
        },
        .azimuth_range = 5,
        .pitch_range = 5,
        .roll_range = 5
};

int reader = 0;

int main(int argc, char **argv) {
        int delay = 0;
        char *name;

        /* Get input from user for a name and reader/writer */
        if (argc == 3 || argc == 4) {
                if (argv[1][0] == 'r') {
                        reader = 1;
                } else if (argv[1][0] == 'w') {
                        reader = 0;
                } else {
                        printf("usage: ./test [r|w] <name>\n");
                }

                name = argv[2];

                if (argc == 4) {
                        delay = 1;
                }
        } else {
                printf("usage: ./test [r|w] <name>\n");
        }

        while (1) {
                long error;
                printf("%s about to acquire the lock.\n", name);

                if (reader)     syscall(363, &range); /* read lock */
                else            syscall(364, &range); /* write lock */

                printf("%s acquired lock!\n", name);
                sleep(2);

                if (reader)     syscall(365, &range); /* read unlock */
                else            syscall(366, &range); /* write unlock */

                if (delay) sleep(2);
        }

        return 0;
}