Breaking Eggs And Making Omelettes

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Evaluating Alternate Build Systems

August 27th, 2006 by Multimedia Mike

Even though I am on record as expressing devotion to the Autotools suite, I am not averse to evaluating alternatives. Mostly, I’m interested in a competent build system that can take care of the difficult and tedious stuff pertaining to a build such as dependencies and configuration. I acknowledge that Autotools embody a fair amount of complexity and arcana. The two top contenders to plausibly compete for Autotools’ title appear to be SCons and CMake.


Components

A good baseline for evaluating the capabilities of an alternative is to find a limitation of your current solution and then figure out if the alternative can do that AND everything that the current solution can do. For example, on one of my software projects, I really appreciate that the current Autotools-based solution can:

  • automatically keep track of dependencies
  • manage multiple build targets
  • create multiple build configurations in separate directories, working from the same source tree

But now I need some very fine tweaking of certain build settings, such as being able to static link a particular version of libstdc++ to a binary. I don’t know if any of the common build systems support this without some very serious hacking.

Here is a blog post from someone who has struggled with the very same issues and was able to solve the problem with a hand-crafted Makefile: G Plus Plus Minus One. I have managed to achieve the correct results from the command line. But trying to hack Makefile.am to do the same always ends up with a roundabout veto by the Autotools (i.e., the tools fall back on their preferred method of linking).

Of course, it would be really sweet if I could modify my existing autotools setup to do what I need. I am still diligently researching this possibility. I certainly do not wish to re-tool the whole build system into a hand-crafted, manually maintained Makefile.

Posted in Programming | Comments Off on Evaluating Alternate Build Systems

gcfuse, With Executable Support

August 26th, 2006 by Multimedia Mike

I upgraded my gcfuse utility tonight. The main change was to expose the primary game executable file when browsing a GameCube filesystem. The primary executable is stored as an implicit part of the filesystem, separate from the directory structure. Being able to easily read this file is a useful feature if, for example, someone wishes to get at these executables for the purpose of disassembly.

For example, when mounting the first disc image of one of my few GC games that I have actually completed, Metal Gear Solid:

$ ls -al mount/
total 1
dr-xr-xr-x 4 melanson users         0 Jul 15  2005 .
drwxr-xr-x 7 melanson users       760 Aug 26 21:48 ..
-r--r--r-- 1 melanson users        95 Jul 15  2005 .metadata
dr-xr-xr-x 4 melanson users         0 Jul 15  2005 audio
-r--r--r-- 1 melanson users 426387456 Jul 15  2005 demo.dat
-r--r--r-- 1 melanson users   1988128 Jul 15  2005 metal-gear-solid-the-twin-snakes-exe.dol
-r--r--r-- 1 melanson users      6496 Jul 15  2005 opening.bnr
dr-xr-xr-x 3 melanson users         0 Jul 15  2005 shared
-r--r--r-- 1 melanson users 198715392 Jul 15  2005 stage.dat

The executable file is metal-gear-solid-the-twin-snakes-exe.dol. The filename is a little long, which can happen since it is derived from the game title in the disc metadata, which can be nearly 1000 characters long. The GC executable format is known as DOL, probably short for Dolphin which was the codename of the GameCube during development.

I recognize that I’m likely the only person on the planet who cares about this utility but, hey, it’s my blog and what are blogs for if not to tell the world about the tedious minutiae of an individual’s life?

Related post:

Posted in Game Hacking, Nintendo, Open Source Multimedia | 2 Comments »

8088 Corruption Redux

August 25th, 2006 by Multimedia Mike

Trixter notified me that people just won’t leave his 8088 Corruption exercise alone. One coder has even made a player for the Game Boy Advance. I finally made a MultimediaWiki page for the data format in case anyone wants to carry this further.

Posted in Open Source Multimedia | Comments Off on 8088 Corruption Redux

CD Detection Experiment

August 24th, 2006 by Multimedia Mike

Some years ago, I wrote a program named the CD Detection Experiment to toy around with compact discs. I reference this tool often in my Multimedia Exploration Journal. The end goal was a tool that could analyze a variety of different CD types, including mode 2 discs, Philips CD-I discs, and 3DO discs. All it does is open a raw CD device under Unix, check the first few sectors, and decide what kind of CD is in the drive. I’m trying to remember if this tool preceded my CD-related work for xine or if I used code from my xine work in this program. There is code for Solaris and FreeBSD reading, so I am guessing that I based this on the xine work.


CDCDCD

Anyway, if you care, here is the code. Here is some sample output, from that Deathtrap Dungeon game discussed in this journal entry, the one with a weird mixed mode:

$ ./cdexp /dev/cdrom
CD Detection Experiment
toc:
  first track = 1
   last track = 18

toc entries:
leadout track: MSF: 76:16:18, first frame = 343218
track  1,  data, MSF: 00:02:00, first frame = 150
 mode 1 data
 iso9660 fs signature found
 system id =
 volume id = Deathtrap
track  2, audio, MSF: 28:09:14, first frame = 126689
track  3, audio, MSF: 30:37:58, first frame = 137833
track  4, audio, MSF: 32:37:28, first frame = 146803
track  5, audio, MSF: 35:32:30, first frame = 159930
track  6, audio, MSF: 39:57:58, first frame = 179833
track  7, audio, MSF: 43:07:24, first frame = 194049
track  8, audio, MSF: 45:45:35, first frame = 205910
track  9, audio, MSF: 49:33:19, first frame = 222994
track 10, audio, MSF: 52:38:22, first frame = 236872
track 11, audio, MSF: 55:17:04, first frame = 248779
track 12, audio, MSF: 58:13:66, first frame = 262041
track 13, audio, MSF: 60:28:28, first frame = 272128
track 14, audio, MSF: 62:43:43, first frame = 282268
track 15, audio, MSF: 64:59:33, first frame = 292458
track 16, audio, MSF: 67:14:00, first frame = 302550
track 17, audio, MSF: 75:36:00, first frame = 340200
track 18,  data, MSF: 76:00:00, first frame = 342000
 mode 1 data
 iso9660 fs signature found
 system id =
 volume id = Deathtrap

Posted in Open Source Multimedia | Comments Off on CD Detection Experiment

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