개발하는데 다 이유가 있겠지

---

System Call

---

시스템콜 함수

추가적인 수정이 필요함..

check_addr()

받아온 주소의 유효성을 검사

1. 가상 메모리와 주소가 맵핑된 것이 없는 경우
2. 주소가 유저 스택의 최상단 주소보다 같거나 큰 경우(유저 영역이 아닌 경우)
3. 주소가 NULL인 경우

void check_addr(void *addr)
{
	// 가상메모리와 매핑된게 없거나 유저스택보다 같거나 크고 NULL이면 종료(exit)
	if (pml4_get_page(thread_current()->pml4, addr) == NULL || !is_user_vaddr(addr) || addr == NULL)
	{
		exit(-1);
	}
}

---

halt()

power_off를 호출해서 PintOS를 종료시킴

void halt(void)
{
	power_off();
}

---

exit()

현재 실행 중인 쓰레드의 exit_status 상태를 저장하고 쓰레드를 종료시킴

void exit(int status)
{
	struct thread *curr = thread_current();
	curr->exit_status = status;
	printf("%s: exit(%d)\n", curr->name, status);
	thread_exit();
}

---

read()

파일 디스크립터를 이용해 파일을 찾아서 버퍼에서 크기만큼 읽어들임

int read(int fd, void *buffer, unsigned size)
{
	check_addr(buffer);

	struct thread *curr = thread_current();
	struct file *curr_file = curr->fdt[fd];

	if (fd < 0 || fd >= 64)
	{
		return -1;
	}

	return file_read(curr_file, buffer, size);
}

---

write()

파일 디스크립터가 1인지 확인하고 버퍼에서 실제로 쓰여진 길이만큼을 반환함

int write(int fd, const void *buffer, unsigned length)
{
	check_addr(buffer);

	if (fd < 1 || fd > 63)
	{
		return -1;
	}
	if (fd == 1)
	{
		putbuf(buffer, length);
	}

	return length;
}

---

create()

사이즈를 체크하고 파일을 생성함

bool create(const char *file, unsigned initial_size)
{
	check_addr(file);

	if (initial_size < 0)
	{
		return false;
	}
	else
	{
		return filesys_create(file, initial_size);
	}
}

---

remove()

파일명으로 파일을 제거

bool remove(const char *file)
{
	check_addr(file);

	return filesys_remove(file);
};

---

open()

파일 디스크립터 테이블에 오픈할 파일을 지정하고 next_fd를 빈 곳을 찾아서 갱신

int open(const char *file)
{
	check_addr(file);

	struct file *curr_file;
	struct thread *curr = thread_current();
	int target;
	curr_file = filesys_open(file);

	if (curr_file == NULL)
	{
		return -1;
	}

	curr->fdt[curr->next_fd] = curr_file; // fd에 파일 주소 삽입
	target = curr->next_fd;
	for (int i = curr->next_fd + 1; i < 64; i++)
	{
		if (curr->fdt[i] == NULL)
		{
			curr->next_fd = i;
			return target;
		}
	}

	return -1;
};

---

close()

현재 실행 중인 쓰레드에서 파일을 닫고 파일 디스크립터 테이블에서 NULL로 갱신

 

void close(int fd)
{
	struct thread *curr = thread_current();
	if (fd != NULL)
	{
		return;
	}
	else
	{
		file_close(curr->fdt[fd]);
		curr->fdt[fd] = NULL;
	}
}

---

filesize()

파일 디스크립터가 유효한지 확인하고 파일의 크기(byte 단위)를 반환(fd 0, 1은 표준 입출력)

int filesize(int fd)
{
	struct thread *curr = thread_current();
	if (fd < 2 || fd > 63)
	{
		return -1;
	}

	struct file *curr_file = curr->fdt[fd];

	if (curr_file == NULL)
	{
		return -1;
	}

	return file_length(curr_file);
};

 

---

 

결 과

pass tests/threads/priority-donate-chain
pass tests/userprog/args-none
pass tests/userprog/args-single
pass tests/userprog/args-multiple
pass tests/userprog/args-many
pass tests/userprog/args-dbl-space
pass tests/userprog/halt
pass tests/userprog/exit
pass tests/userprog/create-normal
pass tests/userprog/create-empty
pass tests/userprog/create-null
pass tests/userprog/create-bad-ptr
pass tests/userprog/create-long
pass tests/userprog/create-exists
pass tests/userprog/create-bound
pass tests/userprog/open-normal
pass tests/userprog/open-missing
pass tests/userprog/open-boundary
pass tests/userprog/open-empty
pass tests/userprog/open-null
pass tests/userprog/open-bad-ptr
pass tests/userprog/open-twice
pass tests/userprog/close-normal
pass tests/userprog/close-twice
pass tests/userprog/close-bad-fd
pass tests/userprog/read-normal
pass tests/userprog/read-bad-ptr
pass tests/userprog/read-boundary
pass tests/userprog/read-zero
pass tests/userprog/read-stdout
pass tests/userprog/read-bad-fd
pass tests/userprog/write-normal
pass tests/userprog/write-bad-ptr
pass tests/userprog/write-boundary
pass tests/userprog/write-zero
pass tests/userprog/write-stdin
pass tests/userprog/write-bad-fd
FAIL tests/userprog/fork-once
FAIL tests/userprog/fork-multiple
FAIL tests/userprog/fork-recursive
FAIL tests/userprog/fork-read
FAIL tests/userprog/fork-close
FAIL tests/userprog/fork-boundary
FAIL tests/userprog/exec-once
FAIL tests/userprog/exec-arg
FAIL tests/userprog/exec-boundary
FAIL tests/userprog/exec-missing
FAIL tests/userprog/exec-bad-ptr
FAIL tests/userprog/exec-read
FAIL tests/userprog/wait-simple
FAIL tests/userprog/wait-twice
FAIL tests/userprog/wait-killed
FAIL tests/userprog/wait-bad-pid
FAIL tests/userprog/multi-recurse
FAIL tests/userprog/multi-child-fd
FAIL tests/userprog/rox-simple
FAIL tests/userprog/rox-child
FAIL tests/userprog/rox-multichild
pass tests/userprog/bad-read
pass tests/userprog/bad-write
pass tests/userprog/bad-read2
pass tests/userprog/bad-write2
pass tests/userprog/bad-jump
pass tests/userprog/bad-jump2
pass tests/filesys/base/lg-create
FAIL tests/filesys/base/lg-full
FAIL tests/filesys/base/lg-random
FAIL tests/filesys/base/lg-seq-block
FAIL tests/filesys/base/lg-seq-random
pass tests/filesys/base/sm-create
FAIL tests/filesys/base/sm-full
FAIL tests/filesys/base/sm-random
FAIL tests/filesys/base/sm-seq-block
FAIL tests/filesys/base/sm-seq-random
FAIL tests/filesys/base/syn-read
FAIL tests/filesys/base/syn-remove
FAIL tests/filesys/base/syn-write
FAIL tests/userprog/no-vm/multi-oom
pass tests/threads/alarm-single
pass tests/threads/alarm-multiple
pass tests/threads/alarm-simultaneous
pass tests/threads/alarm-priority
pass tests/threads/alarm-zero
pass tests/threads/alarm-negative
pass tests/threads/priority-change
pass tests/threads/priority-donate-one
pass tests/threads/priority-donate-multiple
pass tests/threads/priority-donate-multiple2
pass tests/threads/priority-donate-nest
pass tests/threads/priority-donate-sema
pass tests/threads/priority-donate-lower
pass tests/threads/priority-fifo
pass tests/threads/priority-preempt
pass tests/threads/priority-sema
pass tests/threads/priority-condvar
pass tests/threads/priority-donate-chain
33 of 95 tests failed.