/* vi: set sw=4 ts=4: *//* * dblist.c -- directory block list functions * * Copyright 1997 by Theodore Ts'o * * %Begin-Header% * This file may be redistributed under the terms of the GNU Public * License. * %End-Header% * */#include <stdio.h>#if HAVE_UNISTD_H#include <unistd.h>#endif#include <string.h>#include <time.h>#include "ext2_fs.h"#include "ext2fsP.h"static int dir_block_cmp(const void *a, const void *b);/* * Returns the number of directories in the filesystem as reported by * the group descriptors.  Of course, the group descriptors could be * wrong! */errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs){	dgrp_t	i;	ext2_ino_t	num_dirs, max_dirs;	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);	num_dirs = 0;	max_dirs = fs->super->s_inodes_per_group;	for (i = 0; i < fs->group_desc_count; i++) {		if (fs->group_desc[i].bg_used_dirs_count > max_dirs)			num_dirs += max_dirs / 8;		else			num_dirs += fs->group_desc[i].bg_used_dirs_count;	}	if (num_dirs > fs->super->s_inodes_count)		num_dirs = fs->super->s_inodes_count;	*ret_num_dirs = num_dirs;	return 0;}/* * helper function for making a new directory block list (for * initialize and copy). */static errcode_t make_dblist(ext2_filsys fs, ext2_ino_t size, ext2_ino_t count,			     struct ext2_db_entry *list,			     ext2_dblist *ret_dblist){	ext2_dblist	dblist;	errcode_t	retval;	size_t		len;	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);	if ((ret_dblist == 0) && fs->dblist &&	    (fs->dblist->magic == EXT2_ET_MAGIC_DBLIST))		return 0;	retval = ext2fs_get_mem(sizeof(struct ext2_struct_dblist), &dblist);	if (retval)		return retval;	memset(dblist, 0, sizeof(struct ext2_struct_dblist));	dblist->magic = EXT2_ET_MAGIC_DBLIST;	dblist->fs = fs;	if (size)		dblist->size = size;	else {		retval = ext2fs_get_num_dirs(fs, &dblist->size);		if (retval)			goto cleanup;		dblist->size = (dblist->size * 2) + 12;	}	len = (size_t) sizeof(struct ext2_db_entry) * dblist->size;	dblist->count = count;	retval = ext2fs_get_mem(len, &dblist->list);	if (retval)		goto cleanup;	if (list)		memcpy(dblist->list, list, len);	else		memset(dblist->list, 0, len);	if (ret_dblist)		*ret_dblist = dblist;	else		fs->dblist = dblist;	return 0;cleanup:	ext2fs_free_mem(&dblist);	return retval;}/* * Initialize a directory block list */errcode_t ext2fs_init_dblist(ext2_filsys fs, ext2_dblist *ret_dblist){	ext2_dblist	dblist;	errcode_t	retval;	retval = make_dblist(fs, 0, 0, 0, &dblist);	if (retval)		return retval;	dblist->sorted = 1;	if (ret_dblist)		*ret_dblist = dblist;	else		fs->dblist = dblist;	return 0;}/* * Copy a directory block list */errcode_t ext2fs_copy_dblist(ext2_dblist src, ext2_dblist *dest){	ext2_dblist	dblist;	errcode_t	retval;	retval = make_dblist(src->fs, src->size, src->count, src->list,			     &dblist);	if (retval)		return retval;	dblist->sorted = src->sorted;	*dest = dblist;	return 0;}/* * Close a directory block list * * (moved to closefs.c) *//* * Add a directory block to the directory block list */errcode_t ext2fs_add_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk,			       int blockcnt){	struct ext2_db_entry	*new_entry;	errcode_t		retval;	unsigned long		old_size;	EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);	if (dblist->count >= dblist->size) {		old_size = dblist->size * sizeof(struct ext2_db_entry);		dblist->size += 100;		retval = ext2fs_resize_mem(old_size, (size_t) dblist->size *					   sizeof(struct ext2_db_entry),					   &dblist->list);		if (retval) {			dblist->size -= 100;			return retval;		}	}	new_entry = dblist->list + ( (int) dblist->count++);	new_entry->blk = blk;	new_entry->ino = ino;	new_entry->blockcnt = blockcnt;	dblist->sorted = 0;	return 0;}/* * Change the directory block to the directory block list */errcode_t ext2fs_set_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk,			       int blockcnt){	dgrp_t			i;	EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);	for (i=0; i < dblist->count; i++) {		if ((dblist->list[i].ino != ino) ||		    (dblist->list[i].blockcnt != blockcnt))			continue;		dblist->list[i].blk = blk;		dblist->sorted = 0;		return 0;	}	return EXT2_ET_DB_NOT_FOUND;}void ext2fs_dblist_sort(ext2_dblist dblist,			int (*sortfunc)(const void *,						    const void *)){	if (!sortfunc)		sortfunc = dir_block_cmp;	qsort(dblist->list, (size_t) dblist->count,	      sizeof(struct ext2_db_entry), sortfunc);	dblist->sorted = 1;}/* * This function iterates over the directory block list */errcode_t ext2fs_dblist_iterate(ext2_dblist dblist,				int (*func)(ext2_filsys fs,					    struct ext2_db_entry *db_info,					    void	*priv_data),				void *priv_data){	ext2_ino_t	i;	int		ret;	EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST);	if (!dblist->sorted)		ext2fs_dblist_sort(dblist, 0);	for (i=0; i < dblist->count; i++) {		ret = (*func)(dblist->fs, &dblist->list[(int)i], priv_data);		if (ret & DBLIST_ABORT)			return 0;	}	return 0;}static int dir_block_cmp(const void *a, const void *b){	const struct ext2_db_entry *db_a =		(const struct ext2_db_entry *) a;	const struct ext2_db_entry *db_b =		(const struct ext2_db_entry *) b;	if (db_a->blk != db_b->blk)		return (int) (db_a->blk - db_b->blk);	if (db_a->ino != db_b->ino)		return (int) (db_a->ino - db_b->ino);	return (int) (db_a->blockcnt - db_b->blockcnt);}int ext2fs_dblist_count(ext2_dblist dblist){	return (int) dblist->count;}