intf-cdda.txt

mips版本的VLC视频服务器

# Contact CDDB via the HTTP protocol?
# bool, default: 0

- -
cddax-cddb-port

# numeric, default: 8880

- -
cddax-cddb-server

# The server CDDB contacts to get CD info
# string, default: freedb.freedb.org

- -
cddax-debug

An integer (interpreted as a bit mask) which shows additional
debugging information see the section below on debugging for more
information about the bits that can be set.

- - 
cddax-device

What to use if no drive specified. If null, we'll scan for CD
drives with a CD-DA loaded in it.

# string, default: 

-----------------------------------------------------------------
Troubleshooting Guide
-----------------------------------------------------------------

This gives higher-level troubleshooting. More detailed and
lower-level information is given in the next section DEBUGGING. 

Problem: something doesn't work. Start at step -1.

Problem: The program gets a SEGFAULT or gives core dump. Start at step
0.

Problem: I don't get anything playing. I can't even get a playlist of
the CD.
Determination: start at step 1.

Problem: Okay, I something plays menu now. But I don't see information
about the CD in the playlist.
Determination: start at step 5.

-1. (Something doesn't work.)

   A lot of what is put here really is applicable to reporting
   problems and troubleshooting in vlc and the concepts really
   apply to any sort of bug reporting. 

   When reporting a problem it's helpful to have facts:

     a) the version of vlc) you are using

     b) the OS you are running on 

     c) the version of libcdio and/or libcddb you are using 
        versions of libcdio and libcddb can be obtained by running 
          pkg-config --modversion libcdio
          pkg-config --modversion libcddb

     d) what you input or requested (e.g. the full command line entered -
        if it is possible to reproduce the problem by giving a
        commandline that is desirable since it is probably the simplest
        way to convey exactly what was requested)
   
        People often give (some part) of an error message neglecting
        to also include what was requested or entered that led to the
        output.

     e) The setting for this plugin. That is the values of the
        variables that start cddax- listed above. On Unix this can
	generally be found in ~/.vlc/vlcrc
  
     f) Exactly the messages that were what given. You can turn
        increase the verbosity level by setting "verbosity=2" in the
        vlc preferences files. On Unix the preferences file is
        generally in ~/vlc/.vlcrc but there are GUI ways to set this
        too. Give everything that is in the message log.

0. (The program gets a SEGFAULT or gives core dump.)

   Get and send a stack trace. 

   In addition to -1. Make sure the program has been compiled with
   debugging symbols put into the code. This is usually done by having
   the "-g" flag set when compiling the program.

   You can get a strack trace the GNU debugger using the "where"
   command. For example on this might work:

     gdb vlc *name-of-corefile*
     where


1. (I don't get anything playing. I can't even get a playlist of
    the CD.)

   Do you even have the plugin loaded? 

   When you run the vlc GUI, under Settings/Preferences you should see
   a "plugins" expandable list and under that another "access" list do
   you see a expandable entry under "access" labeled "cddax"? If so,
   skip on to step 2.

   a) If no "cddax" expandable list, then the CDDAX plugin isn't
   loaded. Does a shared object exist?  The plugin shared object is
   called "libcddax_plugin.so" It should be in the directory that has
   ...vlc/access. If this isn't around you need to build and install
   the CDDAX plugin.

   b) if libcddax_plugin.so is in the filesystem, there might be a
   loader error; perhaps libcdio is not installed or
   are the wrong version. Use ldd on the file to see that it has all
   of the libraries dependencies satisfied. Also you might be able
   check if there was an attempt to load it by tracking system
   calls. On Linux and other OS's) "strace" can be used to see if the
   file gets accessed. On Solaris use "truss". 

   For example on Linux, among the many line of output when I run
   "strace -e trace=file vlc" I see this along with a lot of other
   output:

   ...
   stat64("/usr/local/lib/vlc/access/libcddax_plugin.so", {st_mode=S_IFREG|0755, st_size=238921, ...}) = 0
   open("/usr/local/lib/vlc/access/libcddax_plugin.so", O_RDONLY) = 5

   The parameters inside the calls may be different depending on where
   vlc is installed and what release is installed. If the the file is
   found and "opened", 
  
   There may also be a message may under "setup/logs".

2. (There plugin was loaded and preferences found.)  In the "cddax" tab
   of preference. An important selection is "cddax-device."  If this is
   set to the empty string, CDDAX will try to scan your drives for a
   suitable device if the driver has the capability to scan for
   drives. However you can set the device to something of your
   choosing. On GNU/Linux, this may be "/dev/cdrom" and on Solaris it
   may be "/vol/dev/aliases/cdrom0".  If you set this field, make sure
   these are correct for your particular setup. For example, I
   generally play out of the DVD device and this is called /dev/dvd
   rather than /dev/cdrom.

3. (CD-DA Setup devices seems correct and there is a CD in the
   drive.)  Bring up the playlist. If you specified only a drive and
   no track, you should see in the playlist a list of tracks on the CD.
   
   a. If not something's wrong like step 2. Another tack may be to try
   to read a disk image of a CD and thus eliminate any problems with
   hardware. If this works, then this is a hardware problem. 

4. (You have a list of entries describing the CD-DA or disk-file of
   a CD-DA image.)

   There should be at least one "track" listed for the CD-DA and track
   1 will end with the digit 1.  If there are NO tracks listed then
   there may be a problem with the that particular medium. So as in
   step 3 you can try a known good sample and perhaps burn a CD from
   that. 

5. <<Fill in info about CDDB hacking>>

-----------------------------------------------------------------
Debugging
-----------------------------------------------------------------

**General vlc debugging...

Before delving to things specific to this plugin, some preparation may
be in order. You'll probably want to configure vlc with "--enable-debug".
plugin with debug information. Instead of "make'ing" with "make", use
"make debug" and instead of installing using "make install" use "make
install-debug". 

I use gdb to debug. Debugging vlc with the entire suite of plugins
under gdb is slow because it has to read in symbol tables from all the
plugins. There are two ways to make loading faster when debugging. The
simplest is just to go to the plugin directory and remove unused
plugins. Another approach is create a new directory and make
(symbolic) links into the complete plugin directory. Another way to
speed up gdb loading is to attach the debugger after vlc has started up
via a command like:

  gdb -p *pid-of-vlc-process*

**cddax debugging...

It's a fact of life that this plugin may be in an incomplete state
and/or will have bugs. So to facilitate tracking down problems we let
you see what's going on dynamically. Various debugging settings will
cause output to appear on vlc's plugin log and/or "standard error"
(assuming you've run vlc in a way that you can capture this).

You think of debug switches as a bit mask, that you specify as an
integers the various "bit" values (given in decimal) are listed below.

   name    value  description
---------- -----  -----------
   META        1  Meta information
   EVENT       2  Trace keyboard events
   MRL         4  MRL debugging
   EXT         8  Calls from external routines
   CALL       16  all calls
   LSN        32  LSN changes
   SEEK       64  Seeks to set location
   CDIO      128  Debugging from CDIO library routines
   CDDB      256  debugging from CDDB library routines

**CD debugging...

The tool cd-info from libcdio can be used to show the contents and
analyze the contents of a CD.

The tool cd-read from libcdio can be used to show the sectors of 
the CD or CD image or extract sectors. 

$Id$