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/*
* directory.c
*
* PURPOSE
* Directory related functions
*
* CONTACTS
* E-mail regarding any portion of the Linux UDF file system should be
* directed to the development team mailing list (run by majordomo):
* linux_udf@hpesjro.fc.hp.com
*
* COPYRIGHT
* This file is distributed under the terms of the GNU General Public
* License (GPL). Copies of the GPL can be obtained from:
* ftp://prep.ai.mit.edu/pub/gnu/GPL
* Each contributing author retains all rights to their own work.
*/
#include "udfdecl.h"
#if defined(__linux__) && defined(__KERNEL__)
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/udf_fs.h>
#else
#include <sys/types.h>
#include <stdio.h>
#include <unistd.h>
#endif
#ifdef __KERNEL__
Uint8 * udf_filead_read(struct inode *dir, Uint8 *tmpad, Uint8 ad_size,
lb_addr fe_loc, int *pos, int *offset, struct buffer_head **bh, int *error)
{
int loffset = *offset;
int block;
Uint8 *ad;
int remainder;
*error = 0;
ad = (Uint8 *)(*bh)->b_data + *offset;
*offset += ad_size;
if (!ad)
{
udf_release_data(*bh);
*error = 1;
return NULL;
}
if (*offset == dir->i_sb->s_blocksize)
{
udf_release_data(*bh);
block = udf_get_lb_pblock(dir->i_sb, fe_loc, ++*pos);
if (!block)
return NULL;
if (!(*bh = udf_tread(dir->i_sb, block)))
return NULL;
}
else if (*offset > dir->i_sb->s_blocksize)
{
ad = tmpad;
remainder = dir->i_sb->s_blocksize - loffset;
memcpy((Uint8 *)ad, (*bh)->b_data + loffset, remainder);
udf_release_data(*bh);
block = udf_get_lb_pblock(dir->i_sb, fe_loc, ++*pos);
if (!block)
return NULL;
if (!((*bh) = udf_tread(dir->i_sb, block)))
return NULL;
memcpy((Uint8 *)ad + remainder, (*bh)->b_data, ad_size - remainder);
*offset = ad_size - remainder;
}
return ad;
}
struct FileIdentDesc *
udf_fileident_read(struct inode *dir, loff_t *nf_pos,
struct udf_fileident_bh *fibh,
struct FileIdentDesc *cfi,
lb_addr *bloc, Uint32 *extoffset,
lb_addr *eloc, Uint32 *elen,
Uint32 *offset, struct buffer_head **bh)
{
struct FileIdentDesc *fi;
int i, num, block;
struct buffer_head * tmp, * bha[16];
fibh->soffset = fibh->eoffset;
if (fibh->eoffset == dir->i_sb->s_blocksize)
{
int lextoffset = *extoffset;
if (udf_next_aext(dir, bloc, extoffset, eloc, elen, bh, 1) !=
EXTENT_RECORDED_ALLOCATED)
{
return NULL;
}
block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset);
(*offset) ++;
if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen)
*offset = 0;
else
*extoffset = lextoffset;
udf_release_data(fibh->sbh);
if (!(fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block)))
return NULL;
fibh->soffset = fibh->eoffset = 0;
if (!(*offset & ((16 >> (dir->i_sb->s_blocksize_bits - 9))-1)))
{
i = 16 >> (dir->i_sb->s_blocksize_bits - 9);
if (i+*offset > (*elen >> dir->i_sb->s_blocksize_bits))
i = (*elen >> dir->i_sb->s_blocksize_bits)-*offset;
for (num=0; i>0; i--)
{
block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset+i);
tmp = udf_tgetblk(dir->i_sb, block);
if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
bha[num++] = tmp;
else
brelse(tmp);
}
if (num)
{
ll_rw_block(READA, num, bha);
for (i=0; i<num; i++)
brelse(bha[i]);
}
}
}
else if (fibh->sbh != fibh->ebh)
{
udf_release_data(fibh->sbh);
fibh->sbh = fibh->ebh;
}
fi = udf_get_fileident(fibh->sbh->b_data, dir->i_sb->s_blocksize,
&(fibh->eoffset));
if (!fi)
return NULL;
*nf_pos += ((fibh->eoffset - fibh->soffset) >> 2);
if (fibh->eoffset <= dir->i_sb->s_blocksize)
{
memcpy((Uint8 *)cfi, (Uint8 *)fi, sizeof(struct FileIdentDesc));
}
else if (fibh->eoffset > dir->i_sb->s_blocksize)
{
int lextoffset = *extoffset;
if (udf_next_aext(dir, bloc, extoffset, eloc, elen, bh, 1) !=
EXTENT_RECORDED_ALLOCATED)
{
return NULL;
}
block = udf_get_lb_pblock(dir->i_sb, *eloc, *offset);
(*offset) ++;
if ((*offset << dir->i_sb->s_blocksize_bits) >= *elen)
*offset = 0;
else
*extoffset = lextoffset;
fibh->soffset -= dir->i_sb->s_blocksize;
fibh->eoffset -= dir->i_sb->s_blocksize;
if (!(fibh->ebh = udf_tread(dir->i_sb, block)))
return NULL;
if (sizeof(struct FileIdentDesc) > - fibh->soffset)
{
int fi_len;
memcpy((Uint8 *)cfi, (Uint8 *)fi, - fibh->soffset);
memcpy((Uint8 *)cfi - fibh->soffset, fibh->ebh->b_data,
sizeof(struct FileIdentDesc) + fibh->soffset);
fi_len = (sizeof(struct FileIdentDesc) + cfi->lengthFileIdent +
le16_to_cpu(cfi->lengthOfImpUse) + 3) & ~3;
*nf_pos += ((fi_len - (fibh->eoffset - fibh->soffset)) >> 2);
fibh->eoffset = fibh->soffset + fi_len;
}
else
{
memcpy((Uint8 *)cfi, (Uint8 *)fi, sizeof(struct FileIdentDesc));
}
}
return fi;
}
#endif
struct FileIdentDesc *
udf_get_fileident(void * buffer, int bufsize, int * offset)
{
struct FileIdentDesc *fi;
int lengthThisIdent;
Uint8 * ptr;
int padlen;
if ( (!buffer) || (!offset) ) {
#ifdef __KERNEL__
udf_debug("invalidparms\n, buffer=%p, offset=%p\n", buffer, offset);
#endif
return NULL;
}
ptr = buffer;
if ( (*offset > 0) && (*offset < bufsize) ) {
ptr += *offset;
}
fi=(struct FileIdentDesc *)ptr;
if (le16_to_cpu(fi->descTag.tagIdent) != TID_FILE_IDENT_DESC)
{
#ifdef __KERNEL__
udf_debug("0x%x != TID_FILE_IDENT_DESC\n",
le16_to_cpu(fi->descTag.tagIdent));
udf_debug("offset: %u sizeof: %lu bufsize: %u\n",
*offset, (unsigned long)sizeof(struct FileIdentDesc), bufsize);
#endif
return NULL;
}
if ( (*offset + sizeof(struct FileIdentDesc)) > bufsize )
{
lengthThisIdent = sizeof(struct FileIdentDesc);
}
else
lengthThisIdent = sizeof(struct FileIdentDesc) +
fi->lengthFileIdent + le16_to_cpu(fi->lengthOfImpUse);
/* we need to figure padding, too! */
padlen = lengthThisIdent % UDF_NAME_PAD;
if (padlen)
lengthThisIdent += (UDF_NAME_PAD - padlen);
*offset = *offset + lengthThisIdent;
return fi;
}
extent_ad *
udf_get_fileextent(void * buffer, int bufsize, int * offset)
{
extent_ad * ext;
struct FileEntry *fe;
Uint8 * ptr;
if ( (!buffer) || (!offset) )
{
#ifdef __KERNEL__
printk(KERN_ERR "udf: udf_get_fileextent() invalidparms\n");
#endif
return NULL;
}
fe = (struct FileEntry *)buffer;
if ( le16_to_cpu(fe->descTag.tagIdent) != TID_FILE_ENTRY )
{
#ifdef __KERNEL__
udf_debug("0x%x != TID_FILE_ENTRY\n",
le16_to_cpu(fe->descTag.tagIdent));
#endif
return NULL;
}
ptr=(Uint8 *)(fe->extendedAttr) + le32_to_cpu(fe->lengthExtendedAttr);
if ( (*offset > 0) && (*offset < le32_to_cpu(fe->lengthAllocDescs)) )
{
ptr += *offset;
}
ext = (extent_ad *)ptr;
*offset = *offset + sizeof(extent_ad);
return ext;
}
short_ad *
udf_get_fileshortad(void * buffer, int maxoffset, int *offset, int inc)
{
short_ad * sa;
Uint8 * ptr;
if ( (!buffer) || (!offset) )
{
#ifdef __KERNEL__
printk(KERN_ERR "udf: udf_get_fileshortad() invalidparms\n");
#endif
return NULL;
}
ptr = (Uint8 *)buffer;
if ( (*offset > 0) && (*offset < maxoffset) )
ptr += *offset;
else
return NULL;
if ((sa = (short_ad *)ptr)->extLength == 0)
return NULL;
else if (inc)
(*offset) += sizeof(short_ad);
return sa;
}
long_ad *
udf_get_filelongad(void * buffer, int maxoffset, int * offset, int inc)
{
long_ad * la;
Uint8 * ptr;
if ( (!buffer) || !(offset) )
{
#ifdef __KERNEL__
printk(KERN_ERR "udf: udf_get_filelongad() invalidparms\n");
#endif
return NULL;
}
ptr = (Uint8 *)buffer;
if ( (*offset > 0) && (*offset < maxoffset) )
ptr += *offset;
else
return NULL;
if ((la = (long_ad *)ptr)->extLength == 0)
return NULL;
else if (inc)
(*offset) += sizeof(long_ad);
return la;
}
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