118 lines
2.9 KiB
C
118 lines
2.9 KiB
C
/*
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* linux/fs/ext/dir.c
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*
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* Copyright (C) 1992 Remy Card (card@masi.ibp.fr)
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*
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* from
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*
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* linux/fs/minix/dir.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* ext directory handling functions
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*/
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#include <asm/segment.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/fs.h>
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#include <linux/ext_fs.h>
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#include <linux/stat.h>
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static int ext_dir_read(struct inode * inode, struct file * filp, char * buf, int count)
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{
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return -EISDIR;
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}
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static int ext_readdir(struct inode *, struct file *, struct dirent *, int);
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static struct file_operations ext_dir_operations = {
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NULL, /* lseek - default */
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ext_dir_read, /* read */
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NULL, /* write - bad */
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ext_readdir, /* readdir */
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NULL, /* select - default */
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NULL, /* ioctl - default */
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NULL, /* mmap */
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NULL, /* no special open code */
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NULL, /* no special release code */
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file_fsync /* fsync */
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};
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/*
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* directories can handle most operations...
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*/
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struct inode_operations ext_dir_inode_operations = {
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&ext_dir_operations, /* default directory file-ops */
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ext_create, /* create */
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ext_lookup, /* lookup */
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ext_link, /* link */
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ext_unlink, /* unlink */
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ext_symlink, /* symlink */
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ext_mkdir, /* mkdir */
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ext_rmdir, /* rmdir */
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ext_mknod, /* mknod */
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ext_rename, /* rename */
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NULL, /* readlink */
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NULL, /* follow_link */
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NULL, /* bmap */
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ext_truncate, /* truncate */
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NULL /* permission */
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};
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static int ext_readdir(struct inode * inode, struct file * filp,
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struct dirent * dirent, int count)
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{
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unsigned int offset,i;
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char c;
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struct buffer_head * bh;
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struct ext_dir_entry * de;
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if (!inode || !S_ISDIR(inode->i_mode))
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return -EBADF;
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if (filp->f_pos % 8 != 0)
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return -EBADF;
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while (filp->f_pos < inode->i_size) {
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offset = filp->f_pos & 1023;
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bh = ext_bread(inode,(filp->f_pos)>>BLOCK_SIZE_BITS,0);
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if (!bh) {
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filp->f_pos += 1024-offset;
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continue;
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}
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de = (struct ext_dir_entry *) (offset + bh->b_data);
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while (offset < 1024 && filp->f_pos < inode->i_size) {
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if (de->rec_len < 8 || de->rec_len % 8 != 0 ||
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de->rec_len < de->name_len + 8 ||
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(de->rec_len + filp->f_pos - 1) / 1024 > (filp->f_pos / 1024)) {
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printk ("ext_readdir: bad dir entry, skipping\n");
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printk ("dev=%d, dir=%d, offset=%d, rec_len=%d, name_len=%d\n",
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inode->i_dev, inode->i_ino, offset, de->rec_len, de->name_len);
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filp->f_pos += 1024-offset;
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if (filp->f_pos > inode->i_size)
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filp->f_pos = inode->i_size;
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continue;
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}
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offset += de->rec_len;
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filp->f_pos += de->rec_len;
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if (de->inode) {
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for (i = 0; i < de->name_len; i++)
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if ((c = de->name[i]) != 0)
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put_fs_byte(c,i+dirent->d_name);
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else
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break;
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if (i) {
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put_fs_long(de->inode,&dirent->d_ino);
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put_fs_byte(0,i+dirent->d_name);
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put_fs_word(i,&dirent->d_reclen);
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brelse(bh);
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return i;
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}
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}
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de = (struct ext_dir_entry *) ((char *) de
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+ de->rec_len);
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}
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brelse(bh);
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}
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return 0;
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}
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