o\input texinfo

     [file version.texi not included]

This file documents GNU CD Input and Control Library

Copyright (C) 2003, 2004 Herbert Valerio Riedel <hvr@gnu.org> and Rocky Bernstein <rocky@panix.com>

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Sections being ``Free Software'' and ``Free Software Needs Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,'' and with the Back-Cover Texts as in (a) below.

(a) The Free Software Foundation's Back-Cover Text is: ``You have freedom to copy and modify this GNU Manual, like GNU software.  Copies published by the Free Software Foundation raise funds for GNU development.''

The GNU Compact Disc Input and Control Library (libcdio)
********************************************************

This file documents GNU CD input and control library

Copyright (C) 2003, 2004 Herbert Valerio Riedel and Rocky Bernstein

History
*******

As a result of the repressive Digital Millenium Copyright Act (DMCA) I became aware of Video CD's (VCD's). Video CD's are not subject to the DMCA and therefore enjoy the protection afforded by copyright but no more. But in order for VCD's to be competitive with DVD's, good tools (including GPL tools) are needed for authoring and playing them. And so through VCD's I became aware of the excellent Video CD tools by Herbert Valerio Riedel which form the vcdimager package.

Although vcdimager is great for authoring, examining and extracting parts of a Video CD, it is not a VCD player. And when I looked at the state of Video CD handling in existing VCD players: xine, MPlayer, and vlc, I was a bit disappointed. None handled playback control, menu selections, or playing still frames and segments from track 1.

Version 0.7.12 of vcdimager was very impressive, however it lacked exportable libraries that could be used in other projects. So with the blessing and encouragement of Herbert Valerio Riedel, I took to extract and create libraries from this code base. The result was two libraries: one to extract information from a VCD which I called libvcdinfo, and another to do the reading and control of a VCD. Well, actually, at this point I should say that a Video CD is really just Video put on a existing well-established Compact Disc or CD format. So the library for this is called libcdio rather than libvcdio.

While on the topic of the name libcdio, I should also explain that the library really doesn't handle writing or output (the final "o" in the name). However it was felt that if I put libcdi that might be confused with a particular CD format called CD-I.

The problem and previous work
*****************************

If around the year 2002 you were to look at the code for a number of open-source CD or media players that work on several platforms such as vlc, MPlayer, xine, or xmms to name but a few, you'd find the code to read a CD sprinked with conditional compilation for this or that platform. That is there was no OS-independent programmer library for CD reading and control even though the technology was over 10 years old; yet there are media players which strive for OS independence.

One early CD player, xmcd by Ti Kan, was I think a bit better than most in that it tried to encapsulate the kinds of CD control mechanisms (SCSI, Linux ioctl, Toshiba, etc.) in a "CD Audio Device Interface Library" called libdi.  However this library is for Audio CD's only and I don't believe this library has been used outside of xmcd.

Another project, Simple DirectMedia Layer also encapsulates CD reading.

     SDL is a library that allows you portable low-level access to a video framebuffer, audio output, mouse, and keyboard. With SDL, it is easy to write portable games which run on ...

Many of the media players mentioned above do in fact can make use of the SDL library but for video output only. Because the encapsulation is over many kinds of I/O (video, joysticks, mice, as well as CD's), I believe that the level of control provided for CD a little bit limited. (However to be fair, it may have only been intended for games and may be suitable for that).  Applications that just want the CD reading and control portion I think will find quite a bit overhead.

Another related project is Jörg Schilling's SCSI library. You can use that to make a non-SCSI CD-ROM act like one that understands SCSI MMC commands which is a neat thing to do. However it is a little weird to have to install drivers just so you can run a particular user-level program. Installing drivers often requires special priviledges and permissions and it is pervasive on a system. It is a little sad that along the way to creating such a SCSI library a library similar to libcdio wasn't created which could be used. Were that the case, this library certainly never would have been written.

At the OS level there is the ``A Linux CD-ROM Standard'' by David van Leeuwen from around 1999. This defines a set of definitions and ioctl's that mask hardware differences of various Compact Disc hardware. It is a great idea, however this ``standard'' lacked adoption on OS's other than GNU/Linux. Or maybe it's the case that the standard on other OS's lacked adoption on GNU/Linux. For example on FreeBSD there ia a ``Common Access Method'' (CAM) used for all SCSI access which seem adopted by GNU/Linux. (And I'm thankful for that since, at least for SCSI MMC commands, it is inordinately complicated and in some places arcane.)

Finally at the hardware level where a similar chaos exists, there has been an attempt to do something similar with the SCSI MMC (multimedia commands). This attempts to provide a uniform command set for CD devices PostScript does for printer commands. (I wrote ``attempts'' because over time the command set has changed and now there are several different commands to do a particular function like read a CD table of contents and some hardware understands some of the version of the commands set but might not others) In contrast to PostScript where there one in theory can write a PostScript program in a uniform ASCII representation and send that to a printer, for MMC although there are common internal structures defined, there is no common syntax for representing the structures or an OS-independent library or API for issuing MMC-commands which a programmer would need to use. Instead each Operating System has its own interface.  For example Adaptec's ASPI or the Microsoft's DeviceIoControl on Microsoft Windows, or IOKit for Apple's OS/X, or FreeBSD's CAM. I've been positively awed at how many different variations and differing levels of complexity there are for doing basically the same thing. How easy it is to issue an SCSI-MMC command from a program varies from easy to very difficult. And mastering the boilerplate code to issue an MMC command on one OS really doesn't help much in figuring out how to do it on another OS. So in libcdio we provide a common (and hopefully simple) API to issue SCSI-MMC commands.

What is in this package (and what's not)
****************************************

The library, libcdio, encapsulates CD-ROM reading and control. Applications wishing to be oblivious of the OS- and device-dependent properties of a CD-ROM can use this library.

Also included is a library, libiso9660, for working with ISO-9660 filesystems.

Some support for disk-image types like cdrdao's TOC, CDRWIN's BIN/CUE and Ahead Nero's NRG format is available, so applications that use this library also have the ability to read disc images as though they were CDs.

Finally, we provide a way to issue SCSI ``MultiMedia Commands'' (MMC). MMC is supported by many hardware CD-ROM manufacturers; and in some cases where a CD-ROM doesn't understand MMC directly, some Operating Systems (such as GNU/Linux, Solaris, or FreeBSD or Microsoft Windows ASPI to name a few) provide the MMC emulation. (This concept of software emulation of a common hardware command language is common for printers such as using ghostscript to private postscript emulation for a non-postscript printer.)

Immediate of the library in this package are the Video CD authoring and ripping tools, VCDImager (http://vcdimager.org), a navigation-capable Video CD plugin and CD-DA plugins for the media players xine (http://xinehq.de) and videolan's vlc (http://videolan.org/vlc).

Also included in the libcdio package is a utility program cd-info which displays CD information: number of tracks, CD-format and if possible basic information about the format.  If libcddb (http://libcdddb.sourceforge.net) is available, the cd-info program will display CDDB matches on CD-DA discs. And if a new enough version of libvcdinfo is available (from the vcdimager project), then cd-info shows basic VCD information. The command cd-drive shows what drivers are available and some basic properties of cd-drives attached to the system. (But media may have to be inserted in order to get this info.)

Other utility programs in the libcdio package are:

cd-drive

     lists out drive capabilities

cd-read
     performs low-level block reading of a CD or CD image,

iso-info

     displays ISO-9660 information from an ISO-9660 image

iso-read

     extracts files from an ISO-9660 image.

At present, there is no support for directing CD Audio control, e.g. playing, stopping, or pausing of a CD-CA where the blocks are not actually read into the computer. Nor is there any support for writing CD's. Nor is there any support for reading or writing DVDs. For some of these, there are other libraries (e.g. libdi, libscg, or libdvdread) may be helpful.

I'm not theoretically opposed to putting support like this into libcdio. However at present there are already many gaps in this package, so narrowing its scope in order to focus on these things I think is a good idea.

CD Formats
**********

Much of what I write in this section can be found elsewhere. See for example http://www.pctechguide.com/08cd-rom.htm or http://www.pcguide.com/ref/cd/format.htm

We give just enough background here to cover Compact Discs and Compact Disc formats that are handled by this library.

The Sony and Philips Corporations invented and Compact Disc (CD) in the early 1980s. The specifications for the layout is often referred to by the color of the cover on the specification.

Red Book
========

The first type of CD that was produced was the Compact Disc Digital Audio (CD-DA) or just plain ``audio CD''. The specification, ICE 908, is commonly called the ``Red Book''. Music CD's are recorded in this format which basically allows for around 74 minutes of audio per disc and for that information to be split up into tracks. Tracks are broken up into "sectors" and each sector contains 2,352 bytes. To play one 44.1 kHz CD-DA sampled audio second, 75 sectors are used.

In libcdio when you you want to read an audio sector, you call cdio_read_audio_sector() or cdio_read_audio_sectors().

Yellow Book
===========

The CD-ROM specification or the ``Yellow Book'' followed a few years later (Standards ISO/IEC 10149), and describes the extension of CD's to store computer data, i.e. CD-ROM (Compact Disk Read Only Memory).

The specification in the Yellow Book defines two modes: Mode1 and Mode2.

ISO 9660
--------

The Yellow Book doesn't specify how data is to be stored on a CD-ROM. It was feared that different companies would implement proprietary data storage formats using this specification, resulting in incompatible data CDs. To prevent this, representatives of major manufacturers met at the High Sierra Hotel and Casino in Lake Tahoe, NV, in 1985, to define a standard for storing data on CDs. This format was nicknamed High Sierra Format. In a slightly modified form it was later adopted as ISO the ISO 9660 standard. This standard is further broken down into 3 "levels", the higher the level, the more permissive.

ISO 9660 Level 1
................

Level 1 ISO 9660 defines names in the 8+3 convention so familiar to MS-DOS: eight characters for the filename, a period, and then three characters for the file type, all in upper case. The allowed characters are A-Z, 0-9, ".", and "_".Level 1 ISO 9660 requires that files occupy a contiguous range of sectors. This allows a file to be specified with a start block and a count. The maximum directory depth is 8. For a table of the characters, see ISO-9660 Character Sets.

ISO 9660 Level 2
................

Level 2 ISO 9660 allows far more flexibility in filenames, but isn't usable on some systems, notably MS-DOS.

ISO 9660 Level 3
................

Level 3 ISO-9660 allows non-contiguous files, useful if the file was written in multiple packets with packet-writing software.

There have been a number of extensions to the ISO 9660 CD-ROM file format. One extension is Microsoft's Joliet specification, designed to resolve a number of deficiencies in the original ISO 9660 Level 1 file system, and in particular to support the long file names used in Windows 95 and subsequent versions of Windows.

Another extension is the Rock Ridge Interchange Protocol (RRIP), which enables the recording of sufficient information to support POSIX File System semantics.

Mode1
-----

Mode 1 is the data storage mode used by to store computer data. There are 3 layers of error correction. A Compact Disc using only this format can hold at most 650 MB. The data is laid out in basically the same way as in and audio CD format, except that the 2,352 bytes of data in each block are broken down further. 2,048 of these bytes are for "real" data. The other 304 bytes are used for an additional level of error detecting and correcting code. This is necessary because data CDs cannot tolerate the loss of a handful of bits now and then, the way audio CDs can.

In libcdio when you you want to read a mode1 sector you call the cdio_read_mode1_sector() or cdio_read_mode1_sectors().

Mode2
-----

Mode 2 data CDs are the same as mode 1 CDs except that the error detecting and correcting codes are omitted. So still there are 2 layers of error correction. A Compact Disc using only this mode can thus hold at most 742 MB. Similar to audio CDs, the mode 2 format provides a more flexible vehicle for storing types of data that do not require high data integrity: for example, graphics and video can use this format. But in contrast to the Red Book standard, different modes can be mixed together; this is the basis for the extensions to the original data CD standards known as CD-ROM Extended Architecture, or CD-ROM XA.  CD-ROM XA formats currently in use are CD-I Bridge formats, Photo CD and Video CD plus Sony's Playstation.

In libcdio when you you want to read a mode1 sector you call the cdio_read_mode2_sector() or cdio_read_mode2_sectors().

Green Book
==========

This was a CD-ROM format developed by Philips for CD-i (an obsolete embedded CD-ROM application allowing limited user user interaction with films, games and educational applications). The format is ISO 9660 compliant and introduced mode 2 form 2 addressing. It also contains XA (Extended Architecture) attributes.

Although some Green Book discs contain CD-i applications which can only be played on a CD-i player, others have films or music videos. Video CDs in Green-Book format are labelled "Digital Video on CD." The Green Book for video is largely superceded by White book CD-ROM which draws on this specification.

White Book
==========

The White Book was released by Sony, Philips, Matsushita, and JVC in 1993, defines the Video CD specification. The White Book is also known as Digital Video (DV).

A Video CD contains one data track recorded in CD-ROM XA Mode 2 Form 2. It is always the first track on the disc (Track 1). The ISO-9660 file structure and a CD-i application program are recorded in this track, as well as the Video CD Information Area which gives general information about the Video Compact Disc. After the data track, video is written in one or more subsequent tracks within the same session. These tracks are also recorded in Mode 2 Form 2.

In libcdio when you you want to read a mode2 format 2 audio sector you call the cdio_read_mode2_sector() or cdio_read_mode2_sectors() setting b_form2 to true.

CD Terminology
**************

tracks --- disc subdivisions
============================

In this section we describe CD properties and terms that we make use of in libcdio.

A CD is formated into a number of tracks, and a CD can hold at most 99 such tracks. This is defined by CDIO_CD_MAX_TRACKS in cdio/sector.h. Between the tracks CD specifications require a ``2 second'' in gap (called a lead-in gap. This is unused space with no ``data'' similar to the space between tracks on an old phonograph. The word ``second'' here really refers to a measure of space and not really necessarily an amount of time. However in the special case that the CD encodes an audio CD or CD-DA, the amount of time to play a gap of this size will take 2 seconds.

The beginning (or inner edge) of the CD is supposed to have a ``2 second'' lead-in gap and there is supposed to be another ``2 second'' lead-out gap at the end (or outer edge) of the CD.

People have discovered that they can put useful data in the various gaps and their equipment can read this, violating the standards but allowing a CD to store more data.

In order to determine the number of tracks on a CD and where they start, commands are used to get this table-of-contents or TOC information. Asking about the start of the lead-out track gives the amount of data stored on the Compact Disk. To make it easy to specify this leadout track, special constant 0xAA (decimal 170) is used to indicate it. This is safe since this is higher than the largest legal track position. In libcdio, CDIO_CDROM_LEADOUT_TRACK is defined to be this special value.

block addressing (MSF, LSN, LBA)
================================

A track is broken up into a number of 2352-byte blocks which we sometimes call sectors. Whereas tracks have to have a gap between them, a block or sector does not. (In libcdio the block size constant is defined using CDIO_CD_FRAMESIZE_RAW).

A Compact Disc has a limit on the number of blocks or sectors.  This values is defined by constant CDIO_CD_MAX_LSN in cdio/sector.h.

One can addressing a block in one of three formats. The oldest format is by it's minute/second/frame number, also referred to as MSF and written in time-like format MM:SS:FF (e.g. 30:01:40). In this notation there are 75 ``frames'' in a ``second,'' and the familiar (if awkward) 60 seconds in a minute. Frame here is what we called a block above. The CD specification defines ``frame'' to be another unit which makes up a block. Very confusing. A frame is also sometimes called a sector, analogous to hard-disk terminalogy.

Even more confusing is using this time-like notation for an address or for a length. Too often people confuse the MSF notation this with an amount of time. A ``second'' (or CDIO_CD_FRAMES_PER_SEC blocks) in this notation is only a second of playing time for something encoded as CD-DA. It does not necessarily represent the amount time that it will take to play a of Video CD---usually you need more blocks than this. Nor does it represent the amount of data used to play a second of an MP3---usually you need fewer blocks than this. It is also not the amount of time your CD-ROM will take to read a ``second'' of data off a Compact Disc: for example a 12x CD player will read 12x CDIO_CD_FRAMES_PER_SEC CDIO_CD_FRAMSIZE_RAW-byte blocks in a one second of time.

Furthermore when programming, it is generally more cumbersome to use an MSF rather than a LBA or LSN described below, since subtraction of two MSF's has the awkwardness akin to subtraction using Roman Numerals.

Probably the simplest way to address a block is to use its LSN or ``logical sector number.'' This just numbers the blocks usually from 0 on. fix me: LSNs can be negative up to the pregap size? The Lead-in and Lead-out gaps described above have LSNs just like any other space on a CD. The last unit of address is a LBA. It is the same as a LSN but the 150 blocks assocated with the initial lead-in is are not counted. So to convert a LBA into an LSN you just add 150. Why the distinction between LBA and LSN? I don't know, perhaps this has something to do with ``multisession'' CDs.

How to use
**********

The libcdio package comes with a number of small example programs in the directory example which demonstrate different aspects of the library and show how to use the library. The source code to all of the examples here are contained on the package.

Other sources for examples would be the larger utility programs cd-drive, cd-info, cd-read, iso-info, and iso-read which are all in the src directory of the libcdio package.  See also Utility Programs.

Example 1: list out tracks and LSNs
===================================

Here we will give an annotated example which can be found in the distribution as example/tracks.c.

      1: #include <stdio.h>
      2: #include <sys/types.h>
      3: #include <cdio/cdio.h>
      4: int
      5: main(int argc, const char *argv[])
      6: {
      7:  CdIo *p_cdio = cdio_open ("/dev/cdrom", DRIVER_UNKNOWN);
      8:  track_t first_track_num = cdio_get_first_track_num(p_cdio);
      9:  track_t num_tracks      = cdio_get_num_tracks(p_cdio);
     10:  int j, i=first_track_num;
     11:
     12:  printf("CD-ROM Track List (%i - %i)\n", first_track_num, num_tracks);
     13
     14:  printf("  #:  LSN\n");
     15:
     16:  for (j = 0; j < num_tracks; i++, j++) {
     17:    lsn_t lsn = cdio_get_track_lsn(p_cdio, i);
     18:    if (CDIO_INVALID_LSN != lsn)
     19:      printf("%3d: %06d\n", (int) i, lsn);
     20:  }
     21:  printf("%3X: %06d  leadout\n", CDIO_CDROM_LEADOUT_TRACK,
     22:         cdio_get_track_lsn(p_cdio, CDIO_CDROM_LEADOUT_TRACK));
     23:  cdio_destroy(p_cdio);
     24:  return 0;
     25: }

Already from the beginning on line 2 we see something odd. The #include <sys/types.h> is needed because libcdio assumes type definitions exist for uint32_t, uint16_t and so on.  Alternatively you change line 2to:

     #define HAVE_SYS_TYPES_H

and <cdio/cdio.h> will insert line 2. If you use GNU autoconf to configure your program, add sys/types.h to AC_HAVE_HEADERS and it will arrange for HAVE_SYS_TYPES_H to get defined. If you don't have <sys/types.h> but have some other include that defines these types, put that instead of line 2. Or you could roll your own typedefs. (Note: In the future, this will probably get ``fixed'' by requiring glib.h.)

Okay after getting over the hurdle of line 2, the next line pretty straightforward: you need to include this to get cdio definitions. One of the types that is defined via line 3 is CdIo and a pointer that is used pretty much in all operations. Line 6 initializes the variable cdio which we will be using in all of the subsequent libcdio calls. It does this via a call to cdio_open().

The second parameter of cdio_open is DRIVER_UNKNOWN. For any given installation a number of Compact Disc device drivers may be available. In particular it's not uncommon to have several drivers that can read CD disk-image formats as well as a driver that handles some CD-ROM piece of hardware. Using DRIVER_UNKNOWN as that second parameter we let the library select a driver amongst those that are available; generally the first hardware driver that is available is the one selected.

Note that in contrast to what is typically done using ioctls to read a CD, you don't issue any sort of CD-ROM read TOC command---that is all done by the driver. Of course, the information that you get from reading the TOC is often desired: many tracks are on the CD, or what number the first one is called. This is done through calls on lines 8 and 9.

For each track, we call a cdio routine to get the logical sector number, cdio_get_track_lsn() on line 17 and print the track number and LSN value. Finally we print out the ``lead-out track'' information and we finally call cdio_destroy() in line 23 to indicate we're done with the CD.

Example 2: list drivers available and default CD device
=======================================================

One thing that's a bit hoaky in Example 1 is hard-coding the name of the device used: /dev/cdrom. Although often this is the name of a CD-ROM device on GNU/Linux and possibly some other Unix derivates, there are many OSs for which use a different device name.

In the next example, we'll let the driver give us the name of the CD-ROM device that is right for it.

      1: #include <stdio.h>
      2: #include <sys/types.h>
      3: #include <cdio/cdio.h>
      4: int
      5: main(int argc, const char *argv[])
      6: {
      7:   CdIo *cdio = cdio_open (NULL, DRIVER_UNKNOWN);
      8:   driver_id_t driver_id;
      9:
     10:  if (NULL != cdio) {
     11:    printf("The driver selected is %s\n", cdio_get_driver_name(cdio));
     12:    printf("The default device for this driver is %s\n\n",
     13:           cdio_get_default_device(cdio));
     14:    cdio_destroy(cdio);
     15:  } else {
     16:    printf("Problem in trying to find a driver.\n\n");
     17:  }
     18:
     19:  for (driver_id=CDIO_MIN_DRIVER; driver_id<=CDIO_MAX_DRIVER; driver_id++)
     20:    if (cdio_have_driver(driver_id))
     21:      printf("We have: %s\n", cdio_driver_describe(driver_id));
     22:    else
     23:      printf("We don't have: %s\n", cdio_driver_describe(driver_id));
     24:  return 0;
     25: }

Example 3: figure out what kind of CD (image) we've got
=======================================================

In this example is a somewhat simplified program to show the use of cdio_guess_cd_type() to  figure out the kind of CD image we've got. This can be found in the distribution as example/sample3.c.

     #ifdef HAVE_CONFIG_H
     # include "config.h"
     #endif
     #include <stdio.h>
     #include <string.h>
     #include <sys/types.h>
     #include <cdio/cdio.h>
     #include <cdio/cd_types.h>

     static void
     print_analysis(cdio_iso_analysis_t cdio_iso_analysis,
     	       cdio_fs_anal_t fs, int first_data, unsigned int num_audio,
     	       track_t num_tracks, track_t first_track_num, CdIo *cdio)
     {
       switch(CDIO_FSTYPE(fs)) {
       case CDIO_FS_AUDIO:
         break;
       case CDIO_FS_ISO_9660:
         printf("CD-ROM with ISO 9660 filesystem");
         if (fs & CDIO_FS_ANAL_JOLIET) {
           printf(" and joliet extension level %d", cdio_iso_analysis.joliet_level);
         }
         if (fs & CDIO_FS_ANAL_ROCKRIDGE)
           printf(" and rockridge extensions");
         printf("\n");
         break;
       case CDIO_FS_ISO_9660_INTERACTIVE:
         printf("CD-ROM with CD-RTOS and ISO 9660 filesystem\n");
         break;
       case CDIO_FS_HIGH_SIERRA:
         printf("CD-ROM with High Sierra filesystem\n");
         break;
       case CDIO_FS_INTERACTIVE:
         printf("CD-Interactive%s\n", num_audio > 0 ? "/Ready" : "");
         break;
       case CDIO_FS_HFS:
         printf("CD-ROM with Macintosh HFS\n");
         break;
       case CDIO_FS_ISO_HFS:
         printf("CD-ROM with both Macintosh HFS and ISO 9660 filesystem\n");
         break;
       case CDIO_FS_UFS:
         printf("CD-ROM with Unix UFS\n");
         break;
       case CDIO_FS_EXT2:
         printf("CD-ROM with Linux second extended filesystem\n");
     	  break;
       case CDIO_FS_3DO:
         printf("CD-ROM with Panasonic 3DO filesystem\n");
         break;
       case CDIO_FS_UNKNOWN:
         printf("CD-ROM with unknown filesystem\n");
         break;
       }
       switch(CDIO_FSTYPE(fs)) {
       case CDIO_FS_ISO_9660:
       case CDIO_FS_ISO_9660_INTERACTIVE:
       case CDIO_FS_ISO_HFS:
         printf("ISO 9660: %i blocks, label `%.32s'\n",
     	   cdio_iso_analysis.isofs_size, cdio_iso_analysis.iso_label);
         break;
       }
       if (first_data == 1 && num_audio > 0)
         printf("mixed mode CD   ");
       if (fs & CDIO_FS_ANAL_XA)
         printf("XA sectors   ");
       if (fs & CDIO_FS_ANAL_MULTISESSION)
         printf("Multisession");
       if (fs & CDIO_FS_ANAL_HIDDEN_TRACK)
         printf("Hidden Track   ");
       if (fs & CDIO_FS_ANAL_PHOTO_CD)
         printf("%sPhoto CD   ",
     		      num_audio > 0 ? " Portfolio " : "");
       if (fs & CDIO_FS_ANAL_CDTV)
         printf("Commodore CDTV   ");
       if (first_data > 1)
         printf("CD-Plus/Extra   ");
       if (fs & CDIO_FS_ANAL_BOOTABLE)
         printf("bootable CD   ");
       if (fs & CDIO_FS_ANAL_VIDEOCD && num_audio == 0) {
         printf("Video CD   ");
       }
       if (fs & CDIO_FS_ANAL_SVCD)
         printf("Super Video CD (SVCD) or Chaoji Video CD (CVD)");
       if (fs & CDIO_FS_ANAL_CVD)
         printf("Chaoji Video CD (CVD)");
       printf("\n");
     }

     int
     main(int argc, const char *argv[])
     {
       CdIo *p_cdio = cdio_open (NULL, DRIVER_UNKNOWN);
       cdio_fs_anal_t fs=0;

       track_t num_tracks;
       track_t first_track_num;
       lsn_t start_track;          /* first sector of track */
       lsn_t data_start =0;        /* start of data area */

       int first_data = -1;        /* # of first data track */
       int first_audio = -1;       /* # of first audio track */
       unsigned int num_data  = 0; /* # of data tracks */
       unsigned int num_audio = 0; /* # of audio tracks */
       unsigned int i;

       if (NULL == p_cdio) {
         printf("Problem in trying to find a driver.\n\n");
         return 1;
       }

       first_track_num = cdio_get_first_track_num(p_cdio);
       num_tracks      = cdio_get_num_tracks(p_cdio);

       /* Count the number of data and audio tracks. */
       for (i = first_track_num; i <= num_tracks; i++) {
         if (TRACK_FORMAT_AUDIO == cdio_get_track_format(p_cdio, i)) {
           num_audio++;
           if (-1 == first_audio) first_audio = i;
         } else {
           num_data++;
           if (-1 == first_data)  first_data = i;
         }
       }

       /* try to find out what sort of CD we have */
       if (0 == num_data) {
         printf("Audio CD\n");
       } else {
         /* we have data track(s) */
         int j;
         cdio_iso_analysis_t cdio_iso_analysis;

         memset(&cdio_iso_analysis, 0, sizeof(cdio_iso_analysis));

         for (j = 2, i = first_data; i <= num_tracks; i++) {
           lsn_t lsn;
           track_format_t track_format = cdio_get_track_format(p_cdio, i);

           lsn = cdio_get_track_lsn(p_cdio, i);

           switch ( track_format ) {
           case TRACK_FORMAT_AUDIO:
           case TRACK_FORMAT_ERROR:
     	break;
           case TRACK_FORMAT_CDI:
           case TRACK_FORMAT_XA:
           case TRACK_FORMAT_DATA:
           case TRACK_FORMAT_PSX:
     	;
           }

           start_track = (i == 1) ? 0 : lsn;

           /* save the start of the data area */
           if (i == first_data)
     	data_start = start_track;

           /* skip tracks which belong to the current walked session */
           if (start_track < data_start + cdio_iso_analysis.isofs_size)
     	continue;

           fs = cdio_guess_cd_type(p_cdio, start_track, i, &cdio_iso_analysis);

           print_analysis(cdio_iso_analysis, fs, first_data, num_audio,
     		     num_tracks, first_track_num, p_cdio);

           if ( !(CDIO_FSTYPE(fs) == CDIO_FS_ISO_9660 ||
     	     CDIO_FSTYPE(fs) == CDIO_FS_ISO_HFS  ||
     	     CDIO_FSTYPE(fs) == CDIO_FS_ISO_9660_INTERACTIVE) )
     	/* no method for non-ISO9660 multisessions */
     	break;
         }
       }
       cdio_destroy(p_cdio);
       return 0;
     }

Example 4: use libiso9660 to extract a file from an ISO-9660 image
==================================================================

Next a program to show using libiso9660 to extract a file from an ISO-9660 image.  This can be found in the distribution as example/iso3.c. A more complete and expanded version of this is iso-read, part of this distribution.

     /* This is the ISO 9660 image. */
     #define ISO9660_IMAGE_PATH "../"
     #define ISO9660_IMAGE ISO9660_IMAGE_PATH "test/copying.iso"

     #define LOCAL_FILENAME "copying"

     #ifdef HAVE_CONFIG_H
     # include "config.h"
     #endif
     #include <sys/types.h>
     #include <cdio/cdio.h>
     #include <cdio/iso9660.h>

     #include <stdio.h>

     #ifdef HAVE_ERRNO_H
     #include <errno.h>
     #endif
     #ifdef HAVE_STRING_H
     #include <string.h>
     #endif
     #ifdef HAVE_UNISTD_H
     #include <unistd.h>
     #endif
     #ifdef HAVE_SYS_TYPES_H
     #include <sys/types.h>
     #endif

     #define my_exit(rc)				\
       fclose (outfd);				\
       free(statbuf);				\
       iso9660_close(iso);				\
       return rc;					\

     int
     main(int argc, const char *argv[])
     {
       iso9660_stat_t *statbuf;
       FILE *outfd;
       int i;

       iso9660_t *iso = iso9660_open (ISO9660_IMAGE);

       if (NULL == iso) {
         fprintf(stderr, "Sorry, couldn't open ISO 9660 image %s\n", ISO9660_IMAGE);
         return 1;
       }

       statbuf = iso9660_ifs_stat_translate (iso, LOCAL_FILENAME);

       if (NULL == statbuf)
         {
           fprintf(stderr,
     	      "Could not get ISO-9660 file information for file %s\n",
     	      LOCAL_FILENAME);
           iso9660_close(iso);
           return 2;
         }

       if (!(outfd = fopen (LOCAL_FILENAME, "wb")))
         {
           perror ("fopen()");
           free(statbuf);
           iso9660_close(iso);
           return 3;
         }

       /* Copy the blocks from the ISO-9660 filesystem to the local filesystem. */
       for (i = 0; i < statbuf->size; i += ISO_BLOCKSIZE)
         {
           char buf[ISO_BLOCKSIZE];

           memset (buf, 0, ISO_BLOCKSIZE);

           if ( ISO_BLOCKSIZE != iso9660_iso_seek_read (iso, buf, statbuf->lsn
     						   + (i / ISO_BLOCKSIZE),
     						   1) )
           {
     	fprintf(stderr, "Error reading ISO 9660 file at lsn %lu\n",
     		(long unsigned int) statbuf->lsn + (i / ISO_BLOCKSIZE));
     	my_exit(4);
           }

          fwrite (buf, ISO_BLOCKSIZE, 1, outfd);

          if (ferror (outfd))
             {
               perror ("fwrite()");
               my_exit(5);
             }
         }

       fflush (outfd);

       /* Make sure the file size has the exact same byte size. Without the
          truncate below, the file will a multiple of ISO_BLOCKSIZE.
        */
       if (ftruncate (fileno (outfd), statbuf->size))
         perror ("ftruncate()");

       my_exit(0);
     }

Example 5: list CD-Text and disc mode info
==========================================

Next a program to show using libcdio to list CD-TEXT data. This can be found in the distribution as example/cdtext.c.

     /* Simple program to list CD-Text info of a Compact Disc using libcdio. */
     #ifdef HAVE_CONFIG_H
     # include "config.h"
     #endif
     #include <stdio.h>
     #include <sys/types.h>
     #include <cdio/cdio.h>
     #include <cdio/cdtext.h>

     static void
     print_cdtext_track_info(CdIo *p_cdio, track_t i_track, const char *message) {
       const cdtext_t *cdtext    = cdio_get_cdtext(p_cdio, 0);
       if (NULL != cdtext) {
         cdtext_field_t i;

         printf("%s\n", message);

         for (i=0; i < MAX_CDTEXT_FIELDS; i++) {
           if (cdtext->field[i]) {
             printf("\t%s: %s\n", cdtext_field2str(i), cdtext->field[i]);
           }
         }
       }

     }

     static void
     print_disc_info(CdIo *p_cdio, track_t i_tracks, track_t i_first_track) {
       track_t i_last_track = i_first_track+i_tracks;
       discmode_t cd_discmode = cdio_get_discmode(p_cdio);

       printf("%s\n", discmode2str[cd_discmode]);

       print_cdtext_track_info(p_cdio, 0, "\nCD-Text for Disc:");
       for ( ; i_first_track < i_last_track; i_first_track++ ) {
         char psz_msg[50];
         sprintf(msg, "CD-Text for Track %d:", i_first_track);
         print_cdtext_track_info(p_cdio, i_first_track, psz_msg);
       }
     }

     int
     main(int argc, const char *argv[])
     {
       track_t i_first_track;
       track_t i_tracks;
       CdIo *p_cdio;
       cdio = cdio_open (NULL, DRIVER_UNKNOWN);
       i_first_track = cdio_get_first_track_num(p_cdio);
       i_tracks      = cdio_get_num_tracks(p_cdio);

       if (NULL == p_cdio) {
         printf("Couldn't find CD\n");
         return 1;
       } else {
         print_disc_info(p_cdio, i_tracks, i_first_track);
       }

       cdio_destroy(p_cdio);

       return 0;
     }

Example 6: Using SCSI-MMC to run an INQURY command
==================================================

Now a program to show issuing a simple SCSI-MMC command (INQUIRY). This MMC command retrieves the vendor, model and firmware revision number of a CD drive. For this command to work, usually a CD to be loaded into the drive; odd since the CD itself is not used.

This can be found in the distribution as example/scsi-mmc1.c.

     #ifdef HAVE_CONFIG_H
     # include "config.h"
     #endif
     #include <stdio.h>
     #include <sys/types.h>
     #include <cdio/cdio.h>
     #include <cdio/scsi_mmc.h>
     #include <string.h>

     /* Set how long do wto wait for SCSI-MMC commands to complete */
     #define DEFAULT_TIMEOUT_MS 10000

     int
     main(int argc, const char *argv[])
     {
       CdIo *p_cdio;

       p_cdio = cdio_open (NULL, DRIVER_UNKNOWN);

       if (NULL == p_cdio) {
         printf("Couldn't find CD\n");
         return 1;
       } else {
         int i_status;                  /* Result of SCSI MMC command */
         char buf[36] = { 0, };         /* Place to hold returned data */
         scsi_mmc_cdb_t cdb = {{0, }};  /* Command Descriptor Block */

         CDIO_MMC_SET_COMMAND(cdb.field, CDIO_MMC_GPCMD_INQUIRY);
         cdb.field[4] = sizeof(buf);

         i_status = scsi_mmc_run_cmd(p_cdio, DEFAULT_TIMEOUT_MS,
     				&cdb, SCSI_MMC_DATA_READ,
     				sizeof(buf), &buf);
         if (i_status == 0) {
           char psz_vendor[CDIO_MMC_HW_VENDOR_LEN+1];
           char psz_model[CDIO_MMC_HW_MODEL_LEN+1];
           char psz_rev[CDIO_MMC_HW_REVISION_LEN+1];

           memcpy(psz_vendor, buf + 8, sizeof(psz_vendor)-1);
           psz_vendor[sizeof(psz_vendor)-1] = '\0';
           memcpy(psz_model,
     	     buf + 8 + CDIO_MMC_HW_VENDOR_LEN,
     	     sizeof(psz_model)-1);
           psz_model[sizeof(psz_model)-1] = '\0';
           memcpy(psz_rev,
     	     buf + 8 + CDIO_MMC_HW_VENDOR_LEN +CDIO_MMC_HW_MODEL_LEN,
     	     sizeof(psz_rev)-1);
           psz_rev[sizeof(psz_rev)-1] = '\0';

           printf("Vendor: %s\nModel: %s\nRevision: %s\n",
     	     psz_vendor, psz_model, psz_rev);
         } else {
           printf("Couldn't get INQUIRY data (vendor, model, and revision\n");
         }
       }

       cdio_destroy(p_cdio);

       return 0;
     }

A list of all sample progrmas in the example directory
======================================================

The exmaple directory contains some simple examples of the use of the libcdio library.

A larger more-complicated example are the cd-drive, cd-info, cd-read, iso-info and iso-info programs in the src directory.

Descriptions of the sample are as follows...

iso1.c

     A program to show using libiso9660 to list files in a directory of an ISO-9660 image.

iso2.c

     A program to show using libiso9660 to extract a file from a CDRWIN cue/bin CD image.

iso3.c

     A program to show using libiso9660 to extract a file from an ISO-9660 image.

cdtext.c

     A program to show CD-Text and CD disc mode info.

drives.c

     A program to show drivers installed and what the default CD-ROM drive is and what CD drives are available.

scsi-mmc1.c

     A program to show issuing a simple SCSI-MMC command (INQUIRY).

scsi-mmc2.c

     A more involved SCSI-MMC command to list CD and drive features from a SCSI-MMC GET_CONFIGURATION command.

tracks.c

     A simple program to list track numbers and logical sector numbers of a Compact Disc using libcdio.

sample2.c

     A simple program to show drivers installed and what the default CD-ROM drive is.

sample3.c

     A simple program to show the use of cdio_guess_cd_type().  Figures out the kind of CD image we've got.

sample4.c

     A slightly improved sample3 program: we handle cdio logging and take an optional CD-location.

Diagnostic programs (cd-info, cd-read, iso-info, iso-read)
**********************************************************

cd-drive
========

cd-drive lists out drive information and information about what hardware drivers are available.

cd-info
=======

cd-info will print out the structure of a CD medium which could either be a Compact Disc in a CD ROM or an CD image. It can try to analyze the medium to give characteristics of the medium, such as how many tracks are in the CD and the format of each track, whether a CD contains a Video CD, CD-DA, PhotoCD, whether a track has an ISO-9660 filesystem.

cd-read
=======

cd-info can be used to read blocks a CD medium which could either be a Compact Disc in a CD ROM or an CD image. You specify the beginning and ending LSN and what mode format to use in the reading.

iso-info
========

iso-info can be used to print out the structure of an ISO 9660 image.

iso-read
========

iso-info can be used to extract a file in an ISO-9660 image.

Operating System Considerations and Drivers
*******************************************

GNU/Linux
=========

There are two CD drive access methods on GNU/Linux: ioctl and SCSI MMC.  GNU/Linux has a rather nice and complete ioctl mechanism. On the other hand, the SCSI mechanism is more universal.

Microsoft
=========

There are two CD drive access methods on Microsoft Windows platforms: ioctl and ASPI.

The ASPI interface specification was developed by Adaptec for sending commands to a SCSI host adapter (such as those controlling CD and DVD drives) and used on Window 9x/NT and later. Emulation for ATAPI drives was added so that the same sets of commands worked those even though the drives might not be SCSI nor might there even be a SCSI controller attached.

However in Windows NT/2K/XP, Microsoft provides their Win32 ioctl interface, and has taken steps to make using ASPI more inaccessible (e.g. requiring adminstrative access to use ASPI).

Solaris
=======

There are two CD drive access methods on Solaris: ATAPI and SCSI. SCSI is preferred when possible.

FreeBSD
=======

There are two CD drive access methods on Solaris: ioctl and CAM (common access method). CAM is preferred when possible; it is however sort of a hybrid and includes some ioctl code.

More work on this driver is needed. Volunteers?

OS X
====

More work on this driver is needed. Volunteers?

ISO-9660 Character Sets
***********************

For a description of where are used see ISO 9660 Level 1.

ISO646 d-Characters
===================

       | 0 1 2 3 4 5 6 7
     --+-----------------
     0 |       0   P
     1 |       1 A Q
     2 |       2 B R
     3 |       3 C S
     4 |       4 D T
     5 |       5 E U
     6 |       6 F V
     7 |       7 G W
     8 |       8 H X
     9 |       9 I Y
     a |         J Z
     b |         K
     c |         L
     d |         M
     e |         N
     f |         O _

ISO646 a-Characters
===================

       | 0 1 2 3 4 5 6 7
     --+-----------------
     0 |       0   P
     1 |     ! 1 A Q
     2 |     " 2 B R
     3 |       3 C S
     4 |       4 D T
     5 |     % 5 E U
     6 |     & 6 F V
     7 |     ' 7 G W
     8 |     ( 8 H X
     9 |     ) 9 I Y
     a |     * : J Z
     b |     + ; K
     c |     , < L
     d |     - = M
     e |     . > N
     f |     / ? O _

CD Image Formats
****************

CDRDAO TOC Format
=================

This is cdrdao's own cd image description format. A snippet from the cdrdao(1) manual page, which you should refer to for more information about this format:

     The toc-file describes what data is written to the CD-R and allows control over track/index positions, pre-gaps and sub-channel information.  It is a simple text file, use your favorite text editor to create it.

CDRWIN BIN/CUE Format
=====================

The format referred to as CDRWIN BIN/CUE Format in this manual is a popular CD image format used in the PC world. Not unlike cdrdao's toc file, the cue file describes the track layout, i.e. how the sectors are to be placed on the CD media. The cue file usually contains a reference to a file traditionally having the .bin extension in its filename, the bin file. This bin file contains the sector data payload which is to be written to the CD medium according to the description in the cue file.

The following is an attempt to describe the subset of the .cue file syntax as used in vcdimager in an EBNF-like notation:

     <cue-document> ::= +( <file-line> +<track-expr> )

     <digit> ::= "0" | "1" ... "8" | "9"
     <number> ::= +<digit>
     <msf> ::= <digit><digit> ":" <digit><digit> ":" <digit><digit>

     <file-line> ::= "FILE" <pathname-expr> <file-type> <EOL>

     <pathname-expr> ::= [ "\"" ] <pathname-str-without-spaces> [ "\"" ]
                       | "\"" <pathname-str> "\""

     <file-type> ::= "BINARY"

     <track-expr> ::= <track-line> [ <flag-line> ]
                      [ <pregap-line> ] *<index-line> [ <postgap-line> ]

     <flag-line> ::= "FLAGS" *<flag-type> <EOL>
     <flag-type> ::= "DCP"

     <track-line> ::= "TRACK" <number> <track-type> <EOL>

     <pregap-line> ::= "PREGAP" <msf> <EOL>

     <index-line> ::= "INDEX" <number> <msf> <EOL>

     <postgap-line> ::= "POSTGAP" <msf> <EOL>

     <track-type> ::= "AUDIO" | "MODE1/2048" | "MODE1/2352"
                    | "MODE2/2336" | "MODE2/2352"

     <comment-line> ::= "REM" *<char> <EOL>

NRG Format
==========

The format referred to as NRG Format in this manual is another popular CD image format. It is available only on Nero software on a Microsoft Windows Operating System. It is proprietary and not generally published, so the information we have comes from guessing based on sample CD images. So support for this is incomplete and using this format is not recommended.

Unlike cdrdao's TOC file the BIN/CUE format everything is contained in one file. that one can edit Meta information such as the number of tracks and track format is contained at the end of the file. This information is not inteded to be edited through a text editor.

Glossary
********

     [file glossary.texi not included]

GNU General Public License
**************************

Version 2, June 1991

     [file gpl.texi not included]

GNU Free Documentation License
******************************

Version 1.1, March 2000

     [file fdl.texi not included]