#include <stdio.h>
#include <stdlib.h>
#include <sched.h>
#include <errno.h>
#include <unistd.h>
#include <sys/syscall.h>

typedef unsigned long long u64;
typedef unsigned int u32;
typedef int s32;

struct sched_attr {
	u32 size;

	u32 sched_policy;
	u64 sched_flags;

	/* SCHED_NORMAL, SCHED_BATCH */
	s32 sched_nice;

	/* SCHED_FIFO, SCHED_RR */
	u32 sched_priority;

	/* SCHED_DEADLINE */
	u64 sched_runtime;
	u64 sched_deadline;
	u64 sched_period;
};

#define sched_getattr(pid, attr, size, flags) syscall(__NR_sched_getattr, pid, attr, size, flags)

void get_prio(void)
{
	int ret;
	int policy;
	struct sched_param param;
	struct sched_attr attr;

	policy = sched_getscheduler(0);
	printf("policy = %d\n", policy);

	ret = sched_getparam(0, &param);
	if (ret == 0) {
		printf("sched_priority = %d\n", param.sched_priority);
	}
	else {
		perror("sched_getparam");
	}

	/*
	 * sched_getattr() は glibcラッパー関数がないので自分で syscall() する
	 */
	ret = sched_getattr(0, &attr, sizeof(attr), 0);
	if (ret == 0) {
		printf("sched_policy = %d\n", attr.sched_policy);
		printf("sched_nice = %d\n", attr.sched_nice);
		printf("sched_priority = %d\n", attr.sched_priority);
	}
	else {
		perror("sched_getattr");
	}
}

int main(int argc, char **argv)
{
	get_prio();
	/* キー入力待ち */
	getchar();

	get_prio();
	/* キー入力待ち */
	getchar();

	return 0;
}