/*
* linux/fs/isofs/dir.c
*
* (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*
* Steve Beynon : Missing last directory entries fixed
* (stephen@askone.demon.co.uk) : 21st June 1996
*
* isofs directory handling functions
*/
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/iso_fs.h>
#include <linux/kernel.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/malloc.h>
#include <linux/sched.h>
#include <linux/locks.h>
#include <asm/segment.h>
static int isofs_readdir(struct inode *, struct file *, void *, filldir_t);
static struct file_operations isofs_dir_operations =
{
NULL, /* lseek - default */
NULL, /* read */
NULL, /* write - bad */
isofs_readdir, /* readdir */
NULL, /* select - default */
NULL, /* ioctl - default */
NULL, /* no special open code */
NULL, /* no special release code */
NULL /* fsync */
};
/*
* directories can handle most operations...
*/
struct inode_operations isofs_dir_inode_operations =
{
&isofs_dir_operations, /* default directory file-ops */
NULL, /* create */
isofs_lookup, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
isofs_bmap, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
static int parent_inode_number(struct inode * inode, struct iso_directory_record * de)
{
int inode_number = inode->i_ino;
if ((inode->i_sb->u.isofs_sb.s_firstdatazone) != inode->i_ino)
inode_number = inode->u.isofs_i.i_backlink;
if (inode_number != -1)
return inode_number;
/* This should never happen, but who knows. Try to be forgiving */
return isofs_lookup_grandparent(inode, find_rock_ridge_relocation(de, inode));
}
static int isofs_name_translate(char * old, int len, char * new)
{
int i, c;
for (i = 0; i < len; i++) {
c = old[i];
if (!c)
break;
if (c >= 'A' && c <= 'Z')
c |= 0x20; /* lower case */
/* Drop trailing '.;1' (ISO9660:1988 7.5.1 requires period) */
if (c == '.' && i == len - 3 && old[i + 1] == ';' && old[i + 2] == '1')
break;
/* Drop trailing ';1' */
if (c == ';' && i == len - 2 && old[i + 1] == '1')
break;
/* Convert remaining ';' to '.' */
if (c == ';')
c = '.';
new[i] = c;
}
return i;
}
/*
* This should _really_ be cleaned up some day..
*/
static int do_isofs_readdir(struct inode *inode, struct file *filp,
void *dirent, filldir_t filldir,
char * tmpname, struct iso_directory_record * tmpde)
{
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
unsigned char bufbits = ISOFS_BUFFER_BITS(inode);
unsigned int block, offset;
int inode_number;
struct buffer_head *bh;
int len, rrflag;
int high_sierra = 0;
char *name;
struct iso_directory_record *de;
offset = filp->f_pos & (bufsize - 1);
block = isofs_bmap(inode, filp->f_pos >> bufbits);
if (!block)
return 0;
if (!(bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size)))
return 0;
while (filp->f_pos < inode->i_size) {
int de_len, next_offset;
#ifdef DEBUG
printk("Block, offset, f_pos: %x %x %x\n",
block, offset, filp->f_pos);
printk("inode->i_size = %x\n",inode->i_size);
#endif
/* Next directory_record on next CDROM sector */
if (offset >= bufsize) {
#ifdef DEBUG
printk("offset >= bufsize\n");
#endif
brelse(bh);
offset = 0;
block = isofs_bmap(inode, (filp->f_pos) >> bufbits);
if (!block)
return 0;
bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size);
if (!bh)
return 0;
continue;
}
de = (struct iso_directory_record *) (bh->b_data + offset);
inode_number = (block << bufbits) + (offset & (bufsize - 1));
de_len = *(unsigned char *) de;
#ifdef DEBUG
printk("de_len = %ld\n", de_len);
#endif
/* If the length byte is zero, we should move on to the next
CDROM sector. If we are at the end of the directory, we
kick out of the while loop. */
if (de_len == 0) {
brelse(bh);
filp->f_pos = ((filp->f_pos & ~(ISOFS_BLOCK_SIZE - 1))
+ ISOFS_BLOCK_SIZE);
offset = 0;
block = isofs_bmap(inode, (filp->f_pos) >> bufbits);
if (!block)
return 0;
bh = breada(inode->i_dev, block, bufsize, filp->f_pos, inode->i_size);
if (!bh)
return 0;
continue;
}
/* Make sure that the entire directory record is in the
current bh block.
If not, put the two halves together in "tmpde" */
next_offset = offset + de_len;
if (next_offset > bufsize) {
#ifdef DEBUG
printk("next_offset (%x) > bufsize (%x)\n",next_offset,bufsize);
#endif
next_offset &= (bufsize - 1);
memcpy(tmpde, de, bufsize - offset);
brelse(bh);
block = isofs_bmap(inode, (filp->f_pos + de_len) >> bufbits);
if (!block)
{
return 0;
}
bh = breada(inode->i_dev, block, bufsize,
filp->f_pos,
inode->i_size);
if (!bh)
{
#ifdef DEBUG
printk("!bh block=%ld, bufsize=%ld\n",block,bufsize);
printk("filp->f_pos = %ld\n",filp->f_pos);
printk("inode->i_size = %ld\n", inode->i_size);
#endif
return 0;
}
memcpy(bufsize - offset + (char *) tmpde, bh->b_data, next_offset);
de = tmpde;
}
offset = next_offset;
/* Handle the case of the '.' directory */
if (de->name_len[0] == 1 && de->name[0] == 0) {
if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino) < 0)
break;
filp->f_pos += de_len;
continue;
}
/* Handle the case of the '..' directory */
if (de->name_len[0] == 1 && de->name[0] == 1) {
inode_number = parent_inode_number(inode, de);
if (inode_number == -1)
break;
if (filldir(dirent, "..", 2, filp->f_pos, inode_number) < 0)
break;
filp->f_pos += de_len;
continue;
}
/* Handle everything else. Do name translation if there
is no Rock Ridge NM field. */
if (inode->i_sb->u.isofs_sb.s_unhide == 'n') {
/* Do not report hidden or associated files */
high_sierra = inode->i_sb->u.isofs_sb.s_high_sierra;
if (de->flags[-high_sierra] & 5) {
filp->f_pos += de_len;
continue;
}
}
/* Check Rock Ridge name translation.. */
len = de->name_len[0];
name = de->name;
rrflag = get_rock_ridge_filename(de, &name, &len, inode);
if (rrflag) {
/* rrflag == 1 means that we have a new name (kmalloced) */
if (rrflag == 1) {
rrflag = filldir(dirent, name, len, filp->f_pos, inode_number);
dcache_add(inode, name, len, inode_number);
kfree(name); /* this was allocated in get_r_r_filename.. */
if (rrflag < 0)
break;
}
filp->f_pos += de_len;
continue;
}
if (inode->i_sb->u.isofs_sb.s_mapping == 'n') {
len = isofs_name_translate(name, len, tmpname);
if (filldir(dirent, tmpname, len, filp->f_pos, inode_number) < 0)
break;
dcache_add(inode, tmpname, len, inode_number);
filp->f_pos += de_len;
continue;
}
if (filldir(dirent, name, len, filp->f_pos, inode_number) < 0)
break;
dcache_add(inode, name, len, inode_number);
filp->f_pos += de_len;
continue;
}
brelse(bh);
return 0;
}
/*
* Handle allocation of temporary space for name translation and
* handling split directory entries.. The real work is done by
* "do_isofs_readdir()".
*/
static int isofs_readdir(struct inode *inode, struct file *filp,
void *dirent, filldir_t filldir)
{
int result;
char * tmpname;
struct iso_directory_record * tmpde;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
tmpname = (char *) __get_free_page(GFP_KERNEL);
if (!tmpname)
return -ENOMEM;
tmpde = (struct iso_directory_record *) (tmpname+256);
result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde);
free_page((unsigned long) tmpname);
return result;
}
