cdfs_namei.c

<B>Digital的Unix操作系统VAX 4.2源码</B>

			u.u_error = EIO; /* XXX */
		*gpp = 0;
		return(u.u_error);
	}

	/*
	 * If a file was recorded in interleave mode, verify the
	 * file unit size and interleave gap size are both multiples
	 * of 2k.
	 */
	lbs = ISOFS_LBS(FS(*gpp));
	if (G_TO_DIR(*gpp)->iso_dir_file_unit_size) {
		if ((G_TO_DIR(*gpp)->iso_dir_file_unit_size * lbs) % 
		    ISO_SECSIZE) {
			printf("cdfs_namei: gnode number %d file unit size %d not 2k multiple\n", 
			       gnumber, 
			       (G_TO_DIR(*gpp)->iso_dir_file_unit_size * lbs));
			gput(*gpp);
			u.u_error = EIO;
			*gpp = 0;
			return(u.u_error);
		}
		if ((G_TO_DIR(*gpp)->iso_dir_inger_gap_size * lbs) % 
		    ISO_SECSIZE) {
			printf("cdfs_namei: gnode number %d file gap size %d not 2k multiple\n", 
			       gnumber, 
			       (G_TO_DIR(*gpp)->iso_dir_inger_gap_size * lbs));
			gput(*gpp);
			u.u_error = EIO;
			*gpp = 0;
			return(u.u_error);
		}
		/*
		 * If a file unit contains an XAR, and it was recorded in 
		 * interleave mode, verify size of XAR is equal to the file 
		 * unit size.
		 */
		if (G_TO_DIR(*gpp)->iso_dir_xar) {
			if (G_TO_DIR(*gpp)->iso_dir_xar != 
			    G_TO_DIR(*gpp)->iso_dir_file_unit_size) {
				printf("cdfs_setuptransfer:  gnode number %d xar size %d != file unit size\n", 
				       gnumber, 
				       G_TO_DIR(*gpp)->iso_dir_xar,
				       G_TO_DIR(*gpp)->iso_dir_file_unit_size);
				gput(*gpp);
				u.u_error = EIO;
				*gpp = 0;
				return(u.u_error);
			}
		}
		if (isodebug1 && G_TO_DIR(*gpp)->iso_dir_file_unit_size)
			printf("cdfs_namei: %s recorded in interleave mode !!!\n", nm);
	} /* file unit size */

	cdfs_gunlock(*gpp);
	return (0);
}


int
cdfs_getnumber(dgp, nm, cred)
	struct gnode *dgp;
	char *nm;
	struct ucred *cred;
{
	int isdotdot = 0;
	int wasdot;
	struct buf *bp;
	struct fs *fs;
	int foundit;
	int gnumber;
	struct iso_dir *tmp_iso_dir;
	struct hsg_dir *tmp_hsg_dir;
	struct iso_idir idir;
	int resid;
	int tsize;
	int lbn, bn;
	int datainbuf, offinbuf;
	unsigned int diskaddr;
	unsigned int isodir_offset;
	unsigned int isodir_reclen;
	union {
		unsigned char incoming[4];
		unsigned int  outgoing;
	} iso_convert_int;
	int rablock, rasize;
	int isiso;
	int length;
	int skip_file;

	fs = FS(dgp);

	if (!strcmp(nm, "."))
		return(dgp->g_number);

	if (fs->fs_format == ISO_9660)
		isiso = 1;
	else
		isiso = 0;
	if (!strcmp(nm, ".."))
		isdotdot = 1;

	resid = dgp->g_size;

	isodir_offset = 0;
	diskaddr = ((unsigned int)G_TO_DIR(dgp)->iso_dir_extent +
	       (unsigned int)G_TO_DIR(dgp)->iso_dir_xar) * 
		       (unsigned int)ISOFS_LBS(fs);
	tsize = 0;
	while (resid && !u.u_error) {
		foundit = 0;
		lbn = isodir_offset / ISOFS_LBS(FS(dgp));
		/*
		 * Since directories cannot be interleaved, datainbuf
		 * and tsize will both equal MAXBSIZE, We are only
		 * interested in bn and offinbuf.
		 */
		bn = cdfs_ibmap(dgp, lbn, &datainbuf, &offinbuf);
		datainbuf = MIN(datainbuf, dgp->g_size - isodir_offset);
		bp = bread(dgp->g_dev, bn, FS(dgp)->fs_ibsize, 
			   (struct gnode *)NULL);
		if (bp->b_flags & B_ERROR) {
			brelse(bp);
			return(0);
		}
		tsize = datainbuf;
		wasdot = 0;
		if (isiso)
			tmp_iso_dir = (struct iso_dir *)
				((unsigned int)bp->b_un.b_addr + offinbuf);
		else
			tmp_hsg_dir = (struct hsg_dir *)
				((unsigned int)bp->b_un.b_addr + offinbuf);
		do {
			skip_file = 0;
			switch (fs->fs_format) {
			      case ISO_9660:
				length = tmp_iso_dir->dir_namelen;
				if (tmp_iso_dir->dir_file_flags&ISO_FLG_DIR) {
					if (tmp_iso_dir->dir_namelen == 1) {
						if (tmp_iso_dir->dir_name[0] == '\0') {
							wasdot = 1;
						} else if (wasdot) {
							wasdot = 0;
							if (isdotdot) {
								foundit = 1;
								goto found;
							}
						}
					}
						
				} else {
					/*
					 * If associated file, or volume seq number
					 * does not match file primary volume descriptor
					 * volume sequence number, skip over file.
					 */
					if ((tmp_iso_dir->dir_file_flags&ISO_FLG_ASSOC) ||
					    tmp_iso_dir->dir_vol_seq_no_lsb !=
					    ISOFS_VOLSEQNUM(fs)) {
						skip_file = 1;
						length = 0;
					}
					/*
					 * Subtract version number is appropriate
					 */
					if ((dgp->g_mp)->m_flags & M_NOVERSION) {
						for(length = 0; length < 
						    tmp_iso_dir->dir_namelen;
						    length++)
							if (tmp_iso_dir->dir_name[length] == ';')
								break;
					}

				}
				if(skip_file == 0 && strlen(nm) == length &&
				   !strncmp(nm, tmp_iso_dir->dir_name,
					    length)) {
					foundit = 1;
					goto found;
				}
				isodir_reclen = tmp_iso_dir->dir_len;
				tmp_iso_dir = (struct iso_dir *)
					((unsigned int)tmp_iso_dir + 
						  isodir_reclen);
				break;
			      default: /* HSG */
				length = tmp_hsg_dir->dir_namelen;
				if (tmp_hsg_dir->dir_file_flags&ISO_FLG_DIR) {
					if (tmp_hsg_dir->dir_namelen == 1) {
						if (tmp_hsg_dir->dir_name[0] == '\0') {
							wasdot = 1;
						} else if (wasdot) {
							wasdot = 0;
							if (isdotdot) {
								foundit = 1;
								goto found;
							}
						}
					}
						
				} else {
					/*
					 * If associated file, or volume seq number
					 * does not match file primary volume descriptor
					 * volume sequence number, skip over file.
					 */
					if ((tmp_hsg_dir->dir_file_flags&ISO_FLG_ASSOC) ||
					    tmp_hsg_dir->dir_vol_seq_no_lsb !=
					    ISOFS_VOLSEQNUM(fs)) {
						skip_file = 1;
						length = 0;
					}
					/*
					 * Subtract version number is appropriate
					 */
					if ((dgp->g_mp)->m_flags & M_NOVERSION) {
						for(length = 0; length < 
						    tmp_hsg_dir->dir_namelen;
						    length++)
							if (tmp_hsg_dir->dir_name[length] == ';')
								break;
					}

				}
				if(skip_file == 0 && strlen(nm) == length &&
				   !strncmp(nm, tmp_hsg_dir->dir_name, 
					    length)) { 
					foundit = 1;
					goto found;
				}
				isodir_reclen = tmp_hsg_dir->dir_len;
				tmp_hsg_dir = (struct hsg_dir *)
					((unsigned int)tmp_hsg_dir + 
						  isodir_reclen);
			} /* switch */

			isodir_offset += isodir_reclen;
			tsize -= isodir_reclen;
			switch (fs->fs_format) {
			      case ISO_9660:
				if ((tsize > 0) && 
				    (tmp_iso_dir->dir_len == 0)) {
					isodir_reclen = ISO_SECSIZE -
						(isodir_offset % ISO_SECSIZE);
					tsize -= isodir_reclen;
					isodir_offset += isodir_reclen;
					tmp_iso_dir = (struct iso_dir *)
						((unsigned int)tmp_iso_dir +
						 isodir_reclen);
				}
				break;
			      default:
				if ((tsize > 0) && 
				    (tmp_hsg_dir->dir_len == 0)) {
					isodir_reclen = ISO_SECSIZE -
						(isodir_offset % ISO_SECSIZE);
					tsize -= isodir_reclen;
					isodir_offset += isodir_reclen;
					tmp_hsg_dir = (struct hsg_dir *)
						((unsigned int)tmp_hsg_dir +
						 isodir_reclen);
				}
			} /* switch */
			if (isodir_offset % ISO_SECSIZE == 0)
				resid -= ISO_SECSIZE;
		} while (tsize > 0);
found:
		if (foundit) {
			/*
			 * Found the correct directory entry.
			 * Set gnumber to disk address of directory
			 * record.
			 */
			switch (fs->fs_format) {
			      case ISO_9660:
				if (tmp_iso_dir->dir_file_flags&ISO_FLG_DIR) {
					bcopy(tmp_iso_dir->dir_extent_lsb, 
					      iso_convert_int.incoming, 
					      sizeof(int));
					gnumber = (iso_convert_int.outgoing +
						   tmp_iso_dir->dir_xar) *
							   (int)ISOFS_LBS(fs);
				} else
					gnumber = diskaddr + isodir_offset;
				break;
			      default:
				if (tmp_hsg_dir->dir_file_flags&ISO_FLG_DIR) {
					bcopy(tmp_hsg_dir->dir_extent_lsb, 
					      iso_convert_int.incoming, 
					      sizeof(int));
					gnumber = (iso_convert_int.outgoing +
						   tmp_hsg_dir->dir_xar) *
							   (int)ISOFS_LBS(fs);
				} else
					gnumber = diskaddr + isodir_offset;
			} /* switch */
			/*
			 * Release buffer.
			 */
			brelse(bp);
			if (isodebug)
				printf("cdfs_getnumber: entry %s number %d\n",
				       nm, gnumber);
			return(gnumber);
		}
		brelse(bp);
	}
	if (isodebug)
		printf("cdfs_getnumber: entry %s not found\n", nm);
	return(0);
}