| /* |
| * linux/fs/minix/dir.c |
| * |
| * Copyright (C) 1991, 1992 Linus Torvalds |
| * |
| * minix directory handling functions |
| */ |
| |
| #include <asm/segment.h> |
| |
| #include <linux/errno.h> |
| #include <linux/fs.h> |
| #include <linux/minix_fs.h> |
| #include <linux/stat.h> |
| |
| static int minix_dir_read(struct inode * inode, struct file * filp, char * buf, int count) |
| { |
| return -EISDIR; |
| } |
| |
| static int minix_readdir(struct inode *, struct file *, struct dirent *, int); |
| |
| static struct file_operations minix_dir_operations = { |
| NULL, /* lseek - default */ |
| minix_dir_read, /* read */ |
| NULL, /* write - bad */ |
| minix_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 minix_dir_inode_operations = { |
| &minix_dir_operations, /* default directory file-ops */ |
| minix_create, /* create */ |
| minix_lookup, /* lookup */ |
| minix_link, /* link */ |
| minix_unlink, /* unlink */ |
| minix_symlink, /* symlink */ |
| minix_mkdir, /* mkdir */ |
| minix_rmdir, /* rmdir */ |
| minix_mknod, /* mknod */ |
| minix_rename, /* rename */ |
| NULL, /* readlink */ |
| NULL, /* follow_link */ |
| NULL, /* bmap */ |
| minix_truncate, /* truncate */ |
| NULL /* permission */ |
| }; |
| |
| static int minix_readdir(struct inode * inode, struct file * filp, |
| struct dirent * dirent, int count) |
| { |
| unsigned int offset,i; |
| char c; |
| struct buffer_head * bh; |
| struct minix_dir_entry * de; |
| struct minix_sb_info * info; |
| |
| if (!inode || !inode->i_sb || !S_ISDIR(inode->i_mode)) |
| return -EBADF; |
| info = &inode->i_sb->u.minix_sb; |
| if (filp->f_pos & (info->s_dirsize - 1)) |
| return -EBADF; |
| while (filp->f_pos < inode->i_size) { |
| offset = filp->f_pos & 1023; |
| bh = minix_bread(inode,(filp->f_pos)>>BLOCK_SIZE_BITS,0); |
| if (!bh) { |
| filp->f_pos += 1024-offset; |
| continue; |
| } |
| while (offset < 1024 && filp->f_pos < inode->i_size) { |
| de = (struct minix_dir_entry *) (offset + bh->b_data); |
| offset += info->s_dirsize; |
| filp->f_pos += info->s_dirsize; |
| if (de->inode) { |
| for (i = 0; i < info->s_namelen; 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; |
| } |
| } |
| } |
| brelse(bh); |
| } |
| return 0; |
| } |