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Commit 7aa123a0 authored by Al Viro's avatar Al Viro
Browse files

[readdir] convert efs 



* sanity checks belong before risky operation, not after it
* don't quit as soon as we'd found an entry

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 52018855

fs/efs/dir.c

+33 −42
Original line number Diff line number Diff line
@@ -7,40 +7,38 @@ 
#include <linux/buffer_head.h>

#include "efs.h"



static int efs_readdir(struct file *, void *, filldir_t);

static int efs_readdir(struct file *, struct dir_context *);



const struct file_operations efs_dir_operations = {

	.llseek		= generic_file_llseek,

	.read		= generic_read_dir,

	.readdir	= efs_readdir,

	.iterate	= efs_readdir,

};



const struct inode_operations efs_dir_inode_operations = {

	.lookup		= efs_lookup,

};



static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) {

	struct inode *inode = file_inode(filp);

	struct buffer_head *bh;



	struct efs_dir		*dirblock;

	struct efs_dentry	*dirslot;

	efs_ino_t		inodenum;

static int efs_readdir(struct file *file, struct dir_context *ctx)

{

	struct inode *inode = file_inode(file);

	efs_block_t		block;

	int			slot, namelen;

	char			*nameptr;

	int			slot;



	if (inode->i_size & (EFS_DIRBSIZE-1))

		printk(KERN_WARNING "EFS: WARNING: readdir(): directory size not a multiple of EFS_DIRBSIZE\n");



	/* work out where this entry can be found */

	block = filp->f_pos >> EFS_DIRBSIZE_BITS;

	block = ctx->pos >> EFS_DIRBSIZE_BITS;



	/* each block contains at most 256 slots */

	slot  = filp->f_pos & 0xff;

	slot  = ctx->pos & 0xff;



	/* look at all blocks */

	while (block < inode->i_blocks) {

		struct efs_dir		*dirblock;

		struct buffer_head *bh;



		/* read the dir block */

		bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
@@ -57,11 +55,14 @@ static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) { 
			break;

		}



		while (slot < dirblock->slots) {

			if (dirblock->space[slot] == 0) {

				slot++;

		for (; slot < dirblock->slots; slot++) {

			struct efs_dentry *dirslot;

			efs_ino_t inodenum;

			const char *nameptr;

			int namelen;



			if (dirblock->space[slot] == 0)

				continue;

			}



			dirslot  = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
@@ -72,39 +73,29 @@ static int efs_readdir(struct file *filp, void *dirent, filldir_t filldir) { 
#ifdef DEBUG

			printk(KERN_DEBUG "EFS: readdir(): block %d slot %d/%d: inode %u, name \"%s\", namelen %u\n", block, slot, dirblock->slots-1, inodenum, nameptr, namelen);

#endif

			if (namelen > 0) {

			if (!namelen)

				continue;

			/* found the next entry */

				filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;



				/* copy filename and data in dirslot */

				filldir(dirent, nameptr, namelen, filp->f_pos, inodenum, DT_UNKNOWN);

			ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;



			/* sanity check */

			if (nameptr - (char *) dirblock + namelen > EFS_DIRBSIZE) {

				printk(KERN_WARNING "EFS: directory entry %d exceeds directory block\n", slot);

					slot++;

				continue;

			}



				/* store position of next slot */

				if (++slot == dirblock->slots) {

					slot = 0;

					block++;

				}

			/* copy filename and data in dirslot */

			if (!dir_emit(ctx, nameptr, namelen, inodenum, DT_UNKNOWN)) {

				brelse(bh);

				filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;

				goto out;

				return 0;

			}

			slot++;

		}

		brelse(bh);



		slot = 0;

		block++;

	}



	filp->f_pos = (block << EFS_DIRBSIZE_BITS) | slot;

out:

	ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;

	return 0;

}