/*
* linux/fs/isofs/dir.c
*
* (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO9660 filesystem.
*
* (C) 1991 Linus Torvalds - minix filesystem
*
* isofs directory handling functions
*/
#ifdef MODULE
#include <linux/module.h>
#endif
#include <linux/errno.h>
#include <asm/segment.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>
#define NAME_OFFSET(de) ((int) ((de)->d_name - (char *) (de)))
#define ROUND_UP(x) (((x)+3) & ~3)
static int isofs_readdir(struct inode *, struct file *, struct dirent *, int);
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 */
isofs_bmap, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
static int isofs_readdir(struct inode * inode, struct file * filp,
struct dirent * dirent, int count)
{
unsigned long bufsize = ISOFS_BUFFER_SIZE(inode);
unsigned char bufbits = ISOFS_BUFFER_BITS(inode);
unsigned int block,offset,i, j;
char c = 0;
int inode_number;
struct buffer_head * bh;
void * cpnt = NULL;
unsigned int old_offset;
int dlen, rrflag;
int high_sierra = 0;
char * dpnt, *dpnt1;
struct iso_directory_record * de;
dpnt1 = NULL;
if (!inode || !S_ISDIR(inode->i_mode))
return -EBADF;
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) {
#ifdef DEBUG
printk("Block, offset, f_pos: %x %x %x\n",
block, offset, filp->f_pos);
#endif
de = (struct iso_directory_record *) (bh->b_data + offset);
inode_number = (block << bufbits) + (offset & (bufsize - 1));
/* 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 (*((unsigned char *) de) == 0) {
brelse(bh);
offset = 0;
filp->f_pos = ((filp->f_pos & ~(ISOFS_BLOCK_SIZE - 1))
+ ISOFS_BLOCK_SIZE);
block = isofs_bmap(inode,(filp->f_pos)>>bufbits);
if (!block
|| !(bh = breada(inode->i_dev, block, bufsize, filp->f_pos,
inode->i_size)))
return 0;
continue;
}
/* Make sure that the entire directory record is in the
current bh block.
If not, we malloc a buffer, and put the two halves together,
so that we can cleanly read the block */
old_offset = offset;
offset += *((unsigned char *) de);
filp->f_pos += *((unsigned char *) de);
if (offset > bufsize) {
unsigned int frag1;
frag1 = bufsize - old_offset;
cpnt = kmalloc(*((unsigned char *) de),GFP_KERNEL);
if (!cpnt) return 0;
memcpy(cpnt, bh->b_data + old_offset, frag1);
de = (struct iso_directory_record *) ((char *)cpnt);
brelse(bh);
offset = filp->f_pos & (bufsize - 1);
block = isofs_bmap(inode,(filp->f_pos)>> bufbits);
if (!block
|| !(bh = breada(inode->i_dev, block, bufsize,
filp->f_pos, inode->i_size))) {
kfree(cpnt);
return 0;
};
memcpy((char *)cpnt+frag1, bh->b_data, offset);
}
/* Handle the case of the '.' directory */
rrflag = 0;
i = 1;
if (de->name_len[0] == 1 && de->name[0] == 0) {
put_fs_byte('.',dirent->d_name);
inode_number = inode->i_ino;
dpnt = ".";
}
/* Handle the case of the '..' directory */
else if (de->name_len[0] == 1 && de->name[0] == 1) {
put_fs_byte('.',dirent->d_name);
put_fs_byte('.',dirent->d_name+1);
i = 2;
dpnt = "..";
if((inode->i_sb->u.isofs_sb.s_firstdatazone) != inode->i_ino)
inode_number = inode->u.isofs_i.i_backlink;
else
inode_number = inode->i_ino;
/* This should never happen, but who knows. Try to be forgiving */
if(inode_number == -1) {
inode_number =
isofs_lookup_grandparent(inode,
find_rock_ridge_relocation(de, inode));
if(inode_number == -1){ /* Should never happen */
printk("Backlink not properly set.\n");
goto out;
};
}
}
/* Handle everything else. Do name translation if there
is no Rock Ridge NM field. */
else {
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) {
if (cpnt) {
kfree(cpnt);
cpnt = NULL;
};
continue;
}
}
dlen = de->name_len[0];
dpnt = de->name;
i = dlen;
rrflag = get_rock_ridge_filename(de, &dpnt, &dlen, inode);
if (rrflag) {
if (rrflag == -1) { /* This is a rock ridge reloc dir */
if (cpnt) {
kfree(cpnt);
cpnt = NULL;
};
continue;
};
i = dlen;
}
else
if(inode->i_sb->u.isofs_sb.s_mapping == 'n') {
dpnt1 = dpnt;
dpnt = kmalloc(dlen, GFP_KERNEL);
if (!dpnt) goto out;
for (i = 0; i < dlen && i < NAME_MAX; i++) {
if (!(c = dpnt1[i])) break;
if (c >= 'A' && c <= 'Z') c |= 0x20; /* lower case */
if (c == '.' && i == dlen-3 && de->name[i+1] == ';' && de->name[i+2] == '1')
break; /* Drop trailing '.;1' (ISO9660:1988 7.5.1 requires period) */
if (c == ';' && i == dlen-2 && de->name[i+1] == '1')
break; /* Drop trailing ';1' */
if (c == ';') c = '.'; /* Convert remaining ';' to '.' */
dpnt[i] = c;
}
}
for(j=0; j<i; j++)
put_fs_byte(dpnt[j],j+dirent->d_name); /* And save it */
if(dpnt1) {
kfree(dpnt);
dpnt = dpnt1;
}
dcache_add(inode, dpnt, i, inode_number);
};
#if 0
printk("Nchar: %d\n",i);
#endif
if (rrflag) kfree(dpnt);
if (cpnt) {
kfree(cpnt);
cpnt = NULL;
};
if (i) {
put_fs_long(inode_number, &dirent->d_ino);
put_fs_byte(0,i+dirent->d_name);
put_fs_word(i,&dirent->d_reclen);
brelse(bh);
return ROUND_UP(NAME_OFFSET(dirent) + i + 1);
}
}
/* We go here for any condition we cannot handle. We also drop through
to here at the end of the directory. */
out:
if (cpnt)
kfree(cpnt);
brelse(bh);
return 0;
}