274 строки
6.5 KiB
C
274 строки
6.5 KiB
C
/*
|
|
* 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/smp_lock.h>
|
|
#include "isofs.h"
|
|
|
|
static int isofs_readdir(struct file *, void *, filldir_t);
|
|
|
|
const 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 '.' */
|
|
/* Also '/' to '.' (broken Acorn-generated ISO9660 images) */
|
|
if (c == ';' || 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 long block, offset, block_saved, offset_saved;
|
|
unsigned long inode_number = 0; /* Quiet GCC */
|
|
struct buffer_head *bh = NULL;
|
|
int len;
|
|
int map;
|
|
int first_de = 1;
|
|
char *p = NULL; /* Quiet GCC */
|
|
struct iso_directory_record *de;
|
|
struct isofs_sb_info *sbi = ISOFS_SB(inode->i_sb);
|
|
|
|
offset = filp->f_pos & (bufsize - 1);
|
|
block = filp->f_pos >> bufbits;
|
|
|
|
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);
|
|
|
|
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;
|
|
}
|
|
|
|
block_saved = block;
|
|
offset_saved = offset;
|
|
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 (first_de) {
|
|
isofs_normalize_block_and_offset(de,
|
|
&block_saved,
|
|
&offset_saved);
|
|
inode_number = isofs_get_ino(block_saved,
|
|
offset_saved,
|
|
bufbits);
|
|
}
|
|
|
|
if (de->flags[-sbi->s_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 = parent_ino(filp->f_dentry);
|
|
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. */
|
|
|
|
/*
|
|
* Do not report hidden files if so instructed, or associated
|
|
* files unless instructed to do so
|
|
*/
|
|
if ((sbi->s_hide == 'y' &&
|
|
(de->flags[-sbi->s_high_sierra] & 1)) ||
|
|
(sbi->s_showassoc =='n' &&
|
|
(de->flags[-sbi->s_high_sierra] & 4))) {
|
|
filp->f_pos += de_len;
|
|
continue;
|
|
}
|
|
|
|
map = 1;
|
|
if (sbi->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 (sbi->s_joliet_level) {
|
|
len = get_joliet_filename(de, tmpname, inode);
|
|
p = tmpname;
|
|
} else
|
|
#endif
|
|
if (sbi->s_mapping == 'a') {
|
|
len = get_acorn_filename(de, tmpname, inode);
|
|
p = tmpname;
|
|
} else
|
|
if (sbi->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 == NULL)
|
|
return -ENOMEM;
|
|
|
|
lock_kernel();
|
|
tmpde = (struct iso_directory_record *) (tmpname+1024);
|
|
|
|
result = do_isofs_readdir(inode, filp, dirent, filldir, tmpname, tmpde);
|
|
|
|
free_page((unsigned long) tmpname);
|
|
unlock_kernel();
|
|
return result;
|
|
}
|