stat.c

/*
 *  viz/fs/stat.c
 *
 *  (C) 2019  VizXu
 */

#include <errno.h>
#include <sys/stat.h>

#include <viz/fs.h>
#include <viz/sched.h>
#include <viz/kernel.h>
#include <asm/segment.h>

static void cp_stat(struct m_inode * inode, struct stat * statbuf)
{
	struct stat tmp;
	int i;

	verify_area(statbuf,sizeof (struct stat));
	tmp.st_dev = inode->i_dev;
	tmp.st_ino = inode->i_num;
	tmp.st_mode = inode->i_mode;
	tmp.st_nlink = inode->i_nlinks;
	tmp.st_uid = inode->i_uid;
	tmp.st_gid = inode->i_gid;
	tmp.st_rdev = inode->i_zone[0];
	tmp.st_size = inode->i_size;
	tmp.st_atime = inode->i_atime;
	tmp.st_mtime = inode->i_mtime;
	tmp.st_ctime = inode->i_ctime;
	for (i=0 ; i<sizeof (tmp) ; i++)
		put_fs_byte(((char *) &tmp)[i],i + (char *) statbuf);
}

int sys_stat(char * filename, struct stat * statbuf)
{
	struct m_inode * inode;

	if (!(inode=namei(filename)))
		return -ENOENT;
	cp_stat(inode,statbuf);
	iput(inode);
	return 0;
}

int sys_lstat(char * filename, struct stat * statbuf)
{
	struct m_inode * inode;

	if (!(inode = lnamei(filename)))
		return -ENOENT;
	cp_stat(inode,statbuf);
	iput(inode);
	return 0;
}

int sys_fstat(unsigned int fd, struct stat * statbuf)
{
	struct file * f;
	struct m_inode * inode;

	if (fd >= NR_OPEN || !(f=current->filp[fd]) || !(inode=f->f_inode))
		return -EBADF;
	cp_stat(inode,statbuf);
	return 0;
}

int sys_readlink(const char * path, char * buf, int bufsiz)
{
	struct m_inode * inode;
	struct buffer_head * bh;
	int i;
	char c;

	if (bufsiz <= 0)
		return -EBADF;
	if (bufsiz > 1023)
		bufsiz = 1023;
	verify_area(buf,bufsiz);
	if (!(inode = lnamei(path)))
		return -ENOENT;
	if (inode->i_zone[0])
		bh = bread(inode->i_dev, inode->i_zone[0]);
	else
		bh = NULL;
	iput(inode);
	if (!bh)
		return 0;
	i = 0;
	while (i<bufsiz && (c = bh->b_data[i])) {
		i++;
		put_fs_byte(c,buf++);
	}
	brelse(bh);
	return i;
}