#!/usr/local/bin/perl -s
#
# take a latex AUX file and change the bibstyle to subset or subset-nocomment
# depending on if the -c flag was given (-c means use comments), then rename
# the modified file to references.aux, run bibtex on it, rename the file
# references.bbl to references.bib and delete references.{aux,blg}.  This
# results in a BibTeX file which can be shipped with the latex source of the
# paper.  The \bibliography{} command in the latex file will need to be changed
# to use the newly generated bibliography.
#
# assumes subset.bst and subset-nocomment.bst are in the input path
#
# V. Khera	07-AUG-1992
# khera@cs.duke.edu

$tmpfile = "refs$$";
$outfile = "references.bib";

$SIG{'INT'} = 'handler';
$SIG{'QUIT'} = 'handler';
$SIG{'TERM'} = 'handler';
$| = 1;				# make sure output is flushed after print.

sub handler {
  local($sig) = @_;
  print "Got a SIG$sig -- cleaning up\n";
  &cleanup;
  exit 1;
}

sub cleanup {
  unlink <$tmpfile.*>;
}

$bibstyle = defined($c) ? "subset" : "subset-nocomment";

die "usage: $0 [-c] <auxfile>\n" unless $#ARGV == 0;

$infile = shift;

# canonicalize the name to end i .aux. assumes file is in current directory,
# even though a path may have been specified.  tough noogies, i say!
$infile =~ s#(.*/)?([^.]*).*#\2.aux#;

die "No such file $infile\n" unless -f $infile;

open(INF,$infile) || die "Cannot read $infile\n";
@auxdata = <INF>;		# slurp the whole file in
close(INF);

# create a new AUX file with subset bibstyle specified.
@result = grep(m/(\\citation|\\bibdata).*/ , @auxdata);
die "No citations or data files specified in $infile\n" unless @result;
push(@result,"\\bibstyle{$bibstyle}\n");

open (OUTF,">$tmpfile.aux") || die "Cannot create temp file\n";
print OUTF @result;
close(OUTF);

print "Running bibtex...\n";

$result = system "bibtex $tmpfile";
die "Error running bibtex\n" unless ($result >> 8) == 0;
rename ("$tmpfile.bbl", $outfile);

print "Output is in $outfile\n";

&cleanup;