gems-kernel/source/THIRDPARTY/linux-old/fs/xiafs/dir.c
2024-06-03 11:16:15 -05:00

123 lines
3.5 KiB
C

/*
* linux/fs/xiafs/dir.c
*
* Copyright (C) Q. Frank Xia, 1993.
*
* Based on Linus' minix/dir.c
* Copyright (C) Linus Torvalds, 1991, 1992.
*
* This software may be redistributed per Linux Copyright.
*/
#include <asm/segment.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/xia_fs.h>
#include <linux/stat.h>
#include "xiafs_mac.h"
static int xiafs_dir_read(struct inode *, struct file *, char *, int);
static int xiafs_readdir(struct inode *, struct file *, struct dirent *, int);
static struct file_operations xiafs_dir_operations = {
NULL, /* lseek - default */
xiafs_dir_read, /* read */
NULL, /* write - bad */
xiafs_readdir, /* readdir */
NULL, /* select - default */
NULL, /* ioctl - default */
NULL, /* mmap */
NULL, /* no special open code */
NULL, /* no special release code */
file_fsync /* default fsync */
};
/*
* directories can handle most operations...
*/
struct inode_operations xiafs_dir_inode_operations = {
&xiafs_dir_operations, /* default directory file-ops */
xiafs_create, /* create */
xiafs_lookup, /* lookup */
xiafs_link, /* link */
xiafs_unlink, /* unlink */
xiafs_symlink, /* symlink */
xiafs_mkdir, /* mkdir */
xiafs_rmdir, /* rmdir */
xiafs_mknod, /* mknod */
xiafs_rename, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
NULL, /* bmap */
xiafs_truncate, /* truncate */
NULL /* permission */
};
static int xiafs_dir_read(struct inode * inode,
struct file * filp, char * buf, int count)
{
return -EISDIR;
}
static int xiafs_readdir(struct inode * inode,
struct file * filp, struct dirent * dirent, int count)
{
u_int offset, i;
struct buffer_head * bh;
struct xiafs_direct * de;
if (!inode || !inode->i_sb || !S_ISDIR(inode->i_mode))
return -EBADF;
if (inode->i_size & (XIAFS_ZSIZE(inode->i_sb) - 1) )
return -EBADF;
while (filp->f_pos < inode->i_size) {
offset = filp->f_pos & (XIAFS_ZSIZE(inode->i_sb) - 1);
bh = xiafs_bread(inode, filp->f_pos >> XIAFS_ZSIZE_BITS(inode->i_sb),0);
if (!bh) {
filp->f_pos += XIAFS_ZSIZE(inode->i_sb)-offset;
continue;
}
de = (struct xiafs_direct *) (offset + bh->b_data);
while (offset < XIAFS_ZSIZE(inode->i_sb) && filp->f_pos < inode->i_size) {
if (de->d_ino > inode->i_sb->u.xiafs_sb.s_ninodes ||
de->d_rec_len < 12 ||
(char *)de+de->d_rec_len > XIAFS_ZSIZE(inode->i_sb)+bh->b_data ||
de->d_name_len < 1 || de->d_name_len + 8 > de->d_rec_len ||
de->d_name_len > _XIAFS_NAME_LEN ||
de->d_name[de->d_name_len] ) {
printk("XIA-FS: bad directory entry (%s %d)\n", WHERE_ERR);
brelse(bh);
return 0;
}
offset += de->d_rec_len;
filp->f_pos += de->d_rec_len;
if (de->d_ino) {
for (i = 0; i < de->d_name_len ; i++)
put_fs_byte(de->d_name[i],i+dirent->d_name);
put_fs_byte(0,i+dirent->d_name);
put_fs_long(de->d_ino,&dirent->d_ino);
put_fs_word(i,&dirent->d_reclen);
brelse(bh);
if (!IS_RDONLY (inode)) {
inode->i_atime=CURRENT_TIME;
inode->i_dirt=1;
}
return i;
}
de = (struct xiafs_direct *) (offset + bh->b_data);
}
brelse(bh);
if (offset > XIAFS_ZSIZE(inode->i_sb)) {
printk("XIA-FS: bad directory (%s %d)\n", WHERE_ERR);
return 0;
}
}
if (!IS_RDONLY (inode)) {
inode->i_atime=CURRENT_TIME;
inode->i_dirt=1;
}
return 0;
}