asi2asm

一款MP3 Player Firmware 的原代码,非常有参考价值

#! /usr/bin/perl

# MP3 Player, Fill in Missing AS31 EQUs, http://www.pjrc.com/tech/mp3
# Copyright (c) 2000, PJRC.COM, LLC

# This is sort of kludge to allow one AS31 file to reference
# symbols (defined with ".equ") from another AS31 file.  The
# incomplete file should be named with ".asi".  The format of
# substituted lines is ".need_equ <symbol> <filename.asm>".
# This script opens the required file and substitutes the .equ
# line requested.

# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.

# 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.


print "; This file was automatically generated by asi2asm.\n";
print "; DO NOT EDIT this file, edit the original .asi source\n\n";

while (<>) {
	$lineno++;
	if (/\s*\.need_equ\s+(\w+)\s+([\w\.]+)/) {
		($sym, $file) = ($1, $2);
		open(ASM, $file) ||
		   die "ERROR: Unable to read \"$file\", line $lineno\n";
		undef($line);
		while (<ASM>) {
			next unless /\s*.equ\s+$sym[\s,]+/;
			$line = $_;
			last;
		}
		close(ASM);
		$line ||
		   die "ERROR: Unable to find \"$sym\" in \"$file\", line $lineno\n";
	}
	print;
}