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