/*
   *  linux/fs/hfs/catalog.c
   *
   * Copyright (C) 1995-1997  Paul H. Hargrove
   * (C) 2003 Ardis Technologies <roman@ardistech.com>
   * This file may be distributed under the terms of the GNU General Public License.
   *
   * This file contains the functions related to the catalog B-tree.
   *
   * Cache code shamelessly stolen from
   *     linux/fs/inode.c Copyright (C) 1991, 1992  Linus Torvalds
   *     re-shamelessly stolen Copyright (C) 1997 Linus Torvalds
   */
  
  #include "hfs_fs.h"
  #include "btree.h"
  
  /*
   * hfs_cat_build_key()
   *
   * Given the ID of the parent and the name build a search key.
   */

  void hfs_cat_build_key(struct super_block *sb, btree_key *key, u32 parent, const struct qstr *name)

  {
  	key->cat.reserved = 0;
  	key->cat.ParID = cpu_to_be32(parent);
  	if (name) {

  		hfs_asc2mac(sb, &key->cat.CName, name);

  		key->key_len = 6 + key->cat.CName.len;
  	} else {
  		memset(&key->cat.CName, 0, sizeof(struct hfs_name));
  		key->key_len = 6;
  	}
  }
  
  static int hfs_cat_build_record(hfs_cat_rec *rec, u32 cnid, struct inode *inode)
  {
  	__be32 mtime = hfs_mtime();
  
  	memset(rec, 0, sizeof(*rec));
  	if (S_ISDIR(inode->i_mode)) {
  		rec->type = HFS_CDR_DIR;
  		rec->dir.DirID = cpu_to_be32(cnid);
  		rec->dir.CrDat = mtime;
  		rec->dir.MdDat = mtime;
  		rec->dir.BkDat = 0;
  		rec->dir.UsrInfo.frView = cpu_to_be16(0xff);
  		return sizeof(struct hfs_cat_dir);
  	} else {
  		/* init some fields for the file record */
  		rec->type = HFS_CDR_FIL;
  		rec->file.Flags = HFS_FIL_USED | HFS_FIL_THD;
  		if (!(inode->i_mode & S_IWUSR))
  			rec->file.Flags |= HFS_FIL_LOCK;
  		rec->file.FlNum = cpu_to_be32(cnid);
  		rec->file.CrDat = mtime;
  		rec->file.MdDat = mtime;
  		rec->file.BkDat = 0;
  		rec->file.UsrWds.fdType = HFS_SB(inode->i_sb)->s_type;
  		rec->file.UsrWds.fdCreator = HFS_SB(inode->i_sb)->s_creator;
  		return sizeof(struct hfs_cat_file);
  	}
  }

  static int hfs_cat_build_thread(struct super_block *sb,
  				hfs_cat_rec *rec, int type,

  				u32 parentid, const struct qstr *name)

  {
  	rec->type = type;
  	memset(rec->thread.reserved, 0, sizeof(rec->thread.reserved));
  	rec->thread.ParID = cpu_to_be32(parentid);

  	hfs_asc2mac(sb, &rec->thread.CName, name);

  	return sizeof(struct hfs_cat_thread);
  }
  
  /*
   * create_entry()
   *
   * Add a new file or directory to the catalog B-tree and
   * return a (struct hfs_cat_entry) for it in '*result'.
   */

  int hfs_cat_create(u32 cnid, struct inode *dir, const struct qstr *str, struct inode *inode)

  {
  	struct hfs_find_data fd;
  	struct super_block *sb;
  	union hfs_cat_rec entry;
  	int entry_size;
  	int err;

  	hfs_dbg(CAT_MOD, "create_cat: %s,%u(%d)
  ",
  		str->name, cnid, inode->i_nlink);

  	if (dir->i_size >= HFS_MAX_VALENCE)
  		return -ENOSPC;
  
  	sb = dir->i_sb;

  	err = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  	if (err)
  		return err;

  	/*
  	 * Fail early and avoid ENOSPC during the btree operations. We may
  	 * have to split the root node at most once.
  	 */
  	err = hfs_bmap_reserve(fd.tree, 2 * fd.tree->depth);
  	if (err)
  		goto err2;

  	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);
  	entry_size = hfs_cat_build_thread(sb, &entry, S_ISDIR(inode->i_mode) ?

  			HFS_CDR_THD : HFS_CDR_FTH,
  			dir->i_ino, str);
  	err = hfs_brec_find(&fd);
  	if (err != -ENOENT) {
  		if (!err)
  			err = -EEXIST;
  		goto err2;
  	}
  	err = hfs_brec_insert(&fd, &entry, entry_size);
  	if (err)
  		goto err2;

  	hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);

  	entry_size = hfs_cat_build_record(&entry, cnid, inode);
  	err = hfs_brec_find(&fd);
  	if (err != -ENOENT) {
  		/* panic? */
  		if (!err)
  			err = -EEXIST;
  		goto err1;
  	}
  	err = hfs_brec_insert(&fd, &entry, entry_size);
  	if (err)
  		goto err1;
  
  	dir->i_size++;

  	dir->i_mtime = dir->i_ctime = current_time(dir);

  	mark_inode_dirty(dir);
  	hfs_find_exit(&fd);
  	return 0;
  
  err1:

  	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);

  	if (!hfs_brec_find(&fd))
  		hfs_brec_remove(&fd);
  err2:
  	hfs_find_exit(&fd);
  	return err;
  }
  
  /*
   * hfs_cat_compare()
   *
   * Description:
   *   This is the comparison function used for the catalog B-tree.  In
   *   comparing catalog B-tree entries, the parent id is the most
   *   significant field (compared as unsigned ints).  The name field is
   *   the least significant (compared in "Macintosh lexical order",
   *   see hfs_strcmp() in string.c)
   * Input Variable(s):
   *   struct hfs_cat_key *key1: pointer to the first key to compare
   *   struct hfs_cat_key *key2: pointer to the second key to compare
   * Output Variable(s):
   *   NONE
   * Returns:
   *   int: negative if key1<key2, positive if key1>key2, and 0 if key1==key2
   * Preconditions:
   *   key1 and key2 point to "valid" (struct hfs_cat_key)s.
   * Postconditions:
   *   This function has no side-effects
   */
  int hfs_cat_keycmp(const btree_key *key1, const btree_key *key2)
  {

  	__be32 k1p, k2p;

  	k1p = key1->cat.ParID;
  	k2p = key2->cat.ParID;

  	if (k1p != k2p)
  		return be32_to_cpu(k1p) < be32_to_cpu(k2p) ? -1 : 1;
  
  	return hfs_strcmp(key1->cat.CName.name, key1->cat.CName.len,
  			  key2->cat.CName.name, key2->cat.CName.len);

  }
  
  /* Try to get a catalog entry for given catalog id */
  // move to read_super???
  int hfs_cat_find_brec(struct super_block *sb, u32 cnid,
  		      struct hfs_find_data *fd)
  {
  	hfs_cat_rec rec;
  	int res, len, type;

  	hfs_cat_build_key(sb, fd->search_key, cnid, NULL);

  	res = hfs_brec_read(fd, &rec, sizeof(rec));
  	if (res)
  		return res;
  
  	type = rec.type;
  	if (type != HFS_CDR_THD && type != HFS_CDR_FTH) {

  		pr_err("found bad thread record in catalog
  ");

  		return -EIO;
  	}
  
  	fd->search_key->cat.ParID = rec.thread.ParID;
  	len = fd->search_key->cat.CName.len = rec.thread.CName.len;

  	if (len > HFS_NAMELEN) {

  		pr_err("bad catalog namelength
  ");

  		return -EIO;
  	}

  	memcpy(fd->search_key->cat.CName.name, rec.thread.CName.name, len);
  	return hfs_brec_find(fd);
  }
  
  
  /*
   * hfs_cat_delete()
   *
   * Delete the indicated file or directory.
   * The associated thread is also removed unless ('with_thread'==0).
   */

  int hfs_cat_delete(u32 cnid, struct inode *dir, const struct qstr *str)

  {
  	struct super_block *sb;
  	struct hfs_find_data fd;

  	struct hfs_readdir_data *rd;

  	int res, type;

  	hfs_dbg(CAT_MOD, "delete_cat: %s,%u
  ", str ? str->name : NULL, cnid);

  	sb = dir->i_sb;

  	res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd);
  	if (res)
  		return res;

  	hfs_cat_build_key(sb, fd.search_key, dir->i_ino, str);

  	res = hfs_brec_find(&fd);
  	if (res)
  		goto out;
  
  	type = hfs_bnode_read_u8(fd.bnode, fd.entryoffset);
  	if (type == HFS_CDR_FIL) {
  		struct hfs_cat_file file;
  		hfs_bnode_read(fd.bnode, &file, fd.entryoffset, sizeof(file));
  		if (be32_to_cpu(file.FlNum) == cnid) {
  #if 0
  			hfs_free_fork(sb, &file, HFS_FK_DATA);
  #endif
  			hfs_free_fork(sb, &file, HFS_FK_RSRC);
  		}
  	}

  	/* we only need to take spinlock for exclusion with ->release() */
  	spin_lock(&HFS_I(dir)->open_dir_lock);

  	list_for_each_entry(rd, &HFS_I(dir)->open_dir_list, list) {

  		if (fd.tree->keycmp(fd.search_key, (void *)&rd->key) < 0)
  			rd->file->f_pos--;
  	}

  	spin_unlock(&HFS_I(dir)->open_dir_lock);

  
  	res = hfs_brec_remove(&fd);
  	if (res)
  		goto out;

  	hfs_cat_build_key(sb, fd.search_key, cnid, NULL);

  	res = hfs_brec_find(&fd);
  	if (!res) {
  		res = hfs_brec_remove(&fd);
  		if (res)
  			goto out;
  	}
  
  	dir->i_size--;

  	dir->i_mtime = dir->i_ctime = current_time(dir);

  	mark_inode_dirty(dir);
  	res = 0;
  out:
  	hfs_find_exit(&fd);
  
  	return res;
  }
  
  /*
   * hfs_cat_move()
   *
   * Rename a file or directory, possibly to a new directory.
   * If the destination exists it is removed and a
   * (struct hfs_cat_entry) for it is returned in '*result'.
   */

  int hfs_cat_move(u32 cnid, struct inode *src_dir, const struct qstr *src_name,
  		 struct inode *dst_dir, const struct qstr *dst_name)

  {
  	struct super_block *sb;
  	struct hfs_find_data src_fd, dst_fd;
  	union hfs_cat_rec entry;
  	int entry_size, type;
  	int err;

  	hfs_dbg(CAT_MOD, "rename_cat: %u - %lu,%s - %lu,%s
  ",
  		cnid, src_dir->i_ino, src_name->name,

  		dst_dir->i_ino, dst_name->name);
  	sb = src_dir->i_sb;

  	err = hfs_find_init(HFS_SB(sb)->cat_tree, &src_fd);
  	if (err)
  		return err;

  	dst_fd = src_fd;

  	/*
  	 * Fail early and avoid ENOSPC during the btree operations. We may
  	 * have to split the root node at most once.
  	 */
  	err = hfs_bmap_reserve(src_fd.tree, 2 * src_fd.tree->depth);
  	if (err)
  		goto out;

  	/* find the old dir entry and read the data */

  	hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);

  	err = hfs_brec_find(&src_fd);
  	if (err)
  		goto out;

  	if (src_fd.entrylength > sizeof(entry) || src_fd.entrylength < 0) {
  		err = -EIO;
  		goto out;
  	}

  
  	hfs_bnode_read(src_fd.bnode, &entry, src_fd.entryoffset,
  			    src_fd.entrylength);
  
  	/* create new dir entry with the data from the old entry */

  	hfs_cat_build_key(sb, dst_fd.search_key, dst_dir->i_ino, dst_name);

  	err = hfs_brec_find(&dst_fd);
  	if (err != -ENOENT) {
  		if (!err)
  			err = -EEXIST;
  		goto out;
  	}
  
  	err = hfs_brec_insert(&dst_fd, &entry, src_fd.entrylength);
  	if (err)
  		goto out;
  	dst_dir->i_size++;

  	dst_dir->i_mtime = dst_dir->i_ctime = current_time(dst_dir);

  	mark_inode_dirty(dst_dir);
  
  	/* finally remove the old entry */

  	hfs_cat_build_key(sb, src_fd.search_key, src_dir->i_ino, src_name);

  	err = hfs_brec_find(&src_fd);
  	if (err)
  		goto out;
  	err = hfs_brec_remove(&src_fd);
  	if (err)
  		goto out;
  	src_dir->i_size--;

  	src_dir->i_mtime = src_dir->i_ctime = current_time(src_dir);

  	mark_inode_dirty(src_dir);
  
  	type = entry.type;
  	if (type == HFS_CDR_FIL && !(entry.file.Flags & HFS_FIL_THD))
  		goto out;
  
  	/* remove old thread entry */

  	hfs_cat_build_key(sb, src_fd.search_key, cnid, NULL);

  	err = hfs_brec_find(&src_fd);
  	if (err)
  		goto out;
  	err = hfs_brec_remove(&src_fd);
  	if (err)
  		goto out;
  
  	/* create new thread entry */

  	hfs_cat_build_key(sb, dst_fd.search_key, cnid, NULL);
  	entry_size = hfs_cat_build_thread(sb, &entry, type == HFS_CDR_FIL ? HFS_CDR_FTH : HFS_CDR_THD,

  					dst_dir->i_ino, dst_name);
  	err = hfs_brec_find(&dst_fd);
  	if (err != -ENOENT) {
  		if (!err)
  			err = -EEXIST;
  		goto out;
  	}
  	err = hfs_brec_insert(&dst_fd, &entry, entry_size);
  out:
  	hfs_bnode_put(dst_fd.bnode);
  	hfs_find_exit(&src_fd);
  	return err;
  }