------------------------------------------------------------------------------ libburnia-project.org scdbackup.sourceforge.net/xorriso_eng.html ------------------------------------------------------------------------------ xorriso. By Thomas Schmitt Integrated sub project of libburnia-project.org but also published via: http://scdbackup.sourceforge.net/xorriso_eng.html http://scdbackup.sourceforge.net/xorriso-0.3.3.tar.gz Copyright (C) 2006-2009 Thomas Schmitt, provided under GPL version 2. ------------------------------------------------------------------------------ xorriso is a program which maps file objects from POSIX compliant filesystems into Rock Ridge enhanced ISO 9660 filesystems and allows session-wise manipulation of such filesystems. It can load the management information of existing ISO images and it writes the session results to optical media or to filesystem objects. Vice versa xorriso is able to restore file objects from ISO 9660 filesystems. Currently it is supported on Linux with kernels >= 2.4 and on FreeBSD versions with ATAPI/CAM support enabled in the kernel, see atapicam(4). A special property of xorriso is that it needs neither an external ISO 9660 formatter program nor an external burn program for CD or DVD but rather incorporates the libraries of libburnia-project.org . By using this software you agree to the disclaimer at the end of this text: "... without even the implied warranty ..." Compilation, First Glimpse, Installation The most simple way to get xorriso from source code is the xorriso standalone tarball. Prerequisites: The tarball contains anything that is needed except libc and libpthread. libreadline and the readline-dev headers will make dialog mode more convenient, but are not mandatory. Obtain xorriso-0.3.3.tar.gz, take it to a directory of your choice and do: tar xzf xorriso-0.3.3.tar.gz cd xorriso-0.3.3 Within that directory execute: ./configure --prefix=/usr make This will produce a binary named ./xorriso/xorriso which you may strip to reduce it in size strip ./xorriso/xorriso You may copy or move it to a directory where it can be found by the shell, or you may execute xorriso at the place where it was built, or you may execute as superuser: make install For general concepts, options and usage examples see man 1 xorriso This man page is part of the tarball as xorriso/xorriso.1 You may get a first glimpse by man ./xorriso/xorriso.1 It gets installed with "make install" but may also be placed manually in the ./man1 directory below one of the directories mentioned in environment variable $MANPATH. The installation creates several alias links pointing to the xorriso binary: xorrisofs starts xorriso with -as mkisofs emulation already enabled xorrecord starts xorriso with -as cdrecord emulation already enabled osirrox starts with -osirrox image-to-disk copying already enabled If you want to avoid dependecy on libreadline although the libreadline development package is installed, then rather build xorriso by: ./configure --prefix=/usr --disable-libreadline make clean ; make Never omit the "make clean" command after switching libreadline enabling. If you want xorriso to report a "Build timestamp" with its option -version: make buildstamped Drives and Disk File Objects The user of xorriso needs rw-permission for the CD burner device. A list of rw-accessible drives can be obtained by xorriso -devices CD devices which offer no rw-permission are invisible to normal users. The superuser should be able to see any usable drive and then set the permissions as needed. The output of xorriso -devices might look like 0 -dev '/dev/sr0' rwrw-- : 'TSSTcorp' 'CDDVDW SH-S203B' 1 -dev '/dev/hda' rwrw-- : 'HL-DT-ST' 'DVD-ROM GDR8162B' Full and insecure enabling of both for everybody would look like chmod a+rw /dev/sr0 /dev/hda This is equivalent to the traditional setup chmod a+x,u+s cdrecord. I strongly discourage to run xorriso with setuid root or via sudo ! It is not checked for the necessary degree of hacker safety. Consider to put all authorized users into group "floppy", to chgrp the device file to that group and to disallow w-access to others. A possible source of problems are hald or other automounters. If you can spot a process "hald-addon-storage" with the address of your desired drive, then consider to kill it. If you cannot get rid of the automounter that easily, try whether it helps to always load the drive tray manually before starting a write run of xorriso. Wait until the drive light is off. Better try to unmount an eventually mounted media before a write run. Besides true optical drives, xorriso can also address disk files as input or output drives. By default paths to files under /dev are accepted only if the device represents a real optical drive. Other device files may be addressed by prepending "stdio:" to the path. Like: xorriso -dev stdio:/dev/sdb ...more arguments... This rule may be changed by xorriso option -drive_class. Prefix "mmc:" causes a path to be accepted only if it is a real optical drive. Testing We are quite sure that libisofs produces accurate representations of the disk files. This opinion is founded on a lot of test burns and checks by a little test program which compares files from the mounted image with the orignals on disk. It uses the normal POSIX filesystem calls, i.e. no libburnia stuff. This program is not installed systemwide but stays in the installation directory of the xorriso tarball as test/compare_file . Usually it is run as -exec payload of a find command. It demands at least three arguments: The path of the first file to compare, the prefix1 to be cut off from path and the prefix2 which gets prepended afterwards to obtain the path of the second file to compare. As further argument there can be -no_ctime which suppresses the comparison of ctime date stamps. The exit value is 0 if no difference was detected, non-0 else. Example: After xorriso ... -pathspecs on -add /=/original/dir -- -commit_eject all mount /media/dvd cd test compare tree /media/dvd with tree /original/dir : find /original/dir -exec ./compare_file '{}' /original/dir /media/dvd ';' \ | less and vice versa: find /media/dvd -exec ./compare_file '{}' /media/dvd /original/dir ';' \ | less File Formats Currently there is only one file format peculiar to xorriso : sector maps which describe the valid and invalid blocks on a media or a disk copy of a media. xorriso creates and reads these file with its option -check_media. The file begins with 32 bytes of cleartext of which the last one is a newline character. The first 25 say "xorriso sector bitmap v2 ", the remaining six characters give the size of the info text as decimal number. This number of bytes follows the first 32 and will not be interpreted by xorriso. They are rather to inform a human reader about the media type and its track layout. After the info text there are two 4 byte signed integers, most significant byte first. The first one, N, gives the number of bits in the following bitmap and the second number S gives the number of 2 KiB blocks governed by a single bit in the map. Then come the bits in form of 8-bit bytes. Data block M is covered by bit B=M/S in the map, bit number B is stored in byte B/8 as bit B%8. A valid readable data block has its bit set to 1. libisoburn xorriso is based on libisofs which does ISO 9600 filesystem aspects and on libburn which does the input and output aspects. Parts of this foundation are accessed via libisoburn, which is closely related to xorriso. libisoburn provides two services: - Encapsulation of coordination between libisofs and libburn. - Emulation of ISO 9660 multi-session on overwriteable media or random access files. The sourcecode of all three libraries is included in the xorriso standalone tarball. It is compiled with xorriso and linked statically. But you may as well get and install releases of libburn and libisofs, in order to be able to install a release of libisoburn which produces libisoburn.so.1 and a matching dynamically linked xorriso binary. This binary is leaner but depends on properly installed libraries of suitable revision. Dynamic library and compile time header requirements for libisoburn-0.3.3 : - libburn.so.4 , version libburn-0.6.0 or higher - libisofs.so.6 , version libisofs-0.6.12 or higher libisoburn and xorriso will not start with libraries which are older than their headers seen at compile time. So compile in the oldest possible installation setup unless you have reason to enforce a newer bug fix level. Standalone xorriso has less runtime dependencies and can be moved more freely. ------------------------------------------------------------------------------ This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA ------------------------------------------------------------------------------ Based on and sub project of: libburnia-project.org By Mario Danic , Vreixo Formoso Thomas Schmitt Copyright (C) 2006-2009 Mario Danic, Vreixo Formoso, Thomas Schmitt. libburnia-project.org is inspired by and in other components still containing parts of old Libburn. By Derek Foreman and Ben Jansens Copyright (C) 2002-2006 Derek Foreman and Ben Jansens