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/*
* linux/fs/isofs/dir.c
*
* (C) 1992, 1993, 1994 Eric Youngdale Modified for ISO 9660 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/slab.h>
#include <linux/sched.h>
#include <linux/locks.h>
#include <linux/config.h>
#include <asm/uaccess.h>
static int isofs_readdir(struct file *, void *, filldir_t);
struct file_operations isofs_dir_operations =
{
read: generic_read_dir,
readdir: isofs_readdir,
};
/*
* directories can handle most operations...
*/
struct inode_operations isofs_dir_inode_operations =
{
lookup: isofs_lookup,
};
int isofs_name_translate(struct iso_directory_record *de, char *new, struct inode *inode)
{
char * old = de->name;
int len = de->name_len[0];
int i;
for (i = 0; i < len; i++) {
unsigned char c = old[i];
if (!c)
break;
if (c >= 'A' && c <= 'Z')
c |= 0x20; /* lower case */
/* Drop trailing '.;1' (ISO 9660:1988 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;
}
/* Acorn extensions written by Matthew Wilcox <willy@bofh.ai> 1998 */
int get_acorn_filename(struct iso_directory_record * de,
char * retname, struct inode * inode)
{
int std;
unsigned char * chr;
int retnamlen = isofs_name_translate(de, retname, inode);
if (retnamlen == 0) return 0;
std = sizeof(struct iso_directory_record) + de->name_len[0];
if (std & 1) std++;
if ((*((unsigned char *) de) - std) != 32) return retnamlen;
chr = ((unsigned char *) de) + std;
if (strncmp(chr, "ARCHIMEDES", 10)) return retnamlen;
if ((*retname == '_') && ((chr[19] & 1) == 1)) *retname = '!';
if (((de->flags[0] & 2) == 0) && (chr[13] == 0xff)
&& ((chr[12] & 0xf0) == 0xf0))
{
retname[retnamlen] = ',';
sprintf(retname+retnamlen+1, "%3.3x",
((chr[12] & 0xf) << 8) | chr[11]);
retnamlen += 4;
}
return retnamlen;
}
/*
* 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 = 0; /* Quiet GCC */
struct buffer_head *bh = NULL;
int len;
int map;
int high_sierra;
int first_de = 1;
char *p = NULL; /* Quiet GCC */
struct iso_directory_record *de;
offset = filp->f_pos & (bufsize - 1);
block = filp->f_pos >> bufbits;
high_sierra = inode->i_sb->u.isofs_sb.s_high_sierra;
while (filp->f_pos < inode->i_size) {
int de_len;
if (!bh) {
bh = isofs_bread(inode, block);
if (!bh)
return 0;
}
de = (struct iso_directory_record *) (bh->b_data + offset);
if (first_de)
inode_number = (bh->b_blocknr << bufbits) + offset;
de_len = *(unsigned char *) de;
/* 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);
bh = NULL;
filp->f_pos = (filp->f_pos + ISOFS_BLOCK_SIZE) & ~(ISOFS_BLOCK_SIZE - 1);
block = filp->f_pos >> bufbits;
offset = 0;
continue;
}
offset += de_len;
/* Make sure we have a full directory entry */
if (offset >= bufsize) {
int slop = bufsize - offset + de_len;
memcpy(tmpde, de, slop);
offset &= bufsize - 1;
block++;
brelse(bh);
bh = NULL;
if (offset) {
bh = isofs_bread(inode, block);
if (!bh)
return 0;
memcpy((void *) tmpde + slop, bh->b_data, offset);
}
de = tmpde;
}
if (de->flags[-high_sierra] & 0x80) {
first_de = 0;
filp->f_pos += de_len;
continue;
}
first_de = 1;
/* 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, DT_DIR) < 0)
break;
filp->f_pos += de_len;
continue;
}
len = 0;
/* Handle the case of the '..' directory */
if (de->name_len[0] == 1 && de->name[0] == 1) {
inode_number = filp->f_dentry->d_parent->d_inode->i_ino;
if (filldir(dirent, "..", 2, filp->f_pos, inode_number, DT_DIR) < 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 */
if (de->flags[-high_sierra] & 5) {
filp->f_pos += de_len;
continue;
}
}
map = 1;
if (inode->i_sb->u.isofs_sb.s_rock) {
len = get_rock_ridge_filename(de, tmpname, inode);
if (len != 0) { /* may be -1 */
p = tmpname;
map = 0;
}
}
if (map) {
#ifdef CONFIG_JOLIET
if (inode->i_sb->u.isofs_sb.s_joliet_level) {
len = get_joliet_filename(de, tmpname, inode);
p = tmpname;
} else
#endif
if (inode->i_sb->u.isofs_sb.s_mapping == 'a') {
len = get_acorn_filename(de, tmpname, inode);
p = tmpname;
} else
if (inode->i_sb->u.isofs_sb.s_mapping == 'n') {
len = isofs_name_translate(de, tmpname, inode);
p = tmpname;
} else {
p = de->name;
len = de->name_len[0];
}
}
if (len > 0) {
if (filldir(dirent, p, len, filp->f_pos, inode_number, DT_UNKNOWN) < 0)
break;
}
filp->f_pos += de_len;
continue;
}
if (bh) 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 file *filp,
void *dirent, filldir_t filldir)
{
int result;
char * tmpname;
struct iso_directory_record * tmpde;
struct inode *inode = filp->f_dentry->d_inode;
tmpname = (char *) __get_free_page(GFP_KERNEL);
if (!tmpname)
return -ENOMEM;
tmpde = (struct iso_directory_record *) (tmpname+1024);
result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde);
free_page((unsigned long) tmpname);
return result;
}
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