#! /usr/bin/perl -w

# Script to automate the incremental merge operation of a branch into
# current cvs workdir, taking into account binary files while still
# avoiding spurious conflicts due to the use of RCS keyword in source
# files.

# Example of use:
#  - initial merge on the 1st syncpoint of a series:
#      utils/cvsmerge syncpoint_gettext1_1
#  - incremental merge of changes between 7th and 8th syncpoints:
#      utils/cvsmerge syncpoint_gettext1_8

use strict;

## parameters

# this may need adjustments as the source tree evolves
our @binarydirs = qw(fonts icons images music sounds);
our @excludeddirs = qw(. .. CVS);

## infer non-binary dirs

our @nonbindirs;
{
  opendir TOP, '.' or die "cannot open top-level dir";
  my @direntries = readdir TOP or die "cannot read top-level dir";
  close TOP;

  foreach my $entry (@direntries) {
    push @nonbindirs, $entry
      if -d $entry and ! grep { $entry eq $_ } (@binarydirs,@excludeddirs);
  }
}

## parse command line

our ($basetag, $targettag);
if (@ARGV == 1) {
  die "single argument must be a syncpoint tag"
    unless $ARGV[0] =~ m/^(syncpoint_.*_)(\d+)$/;

  my ($tagroot, $target) = ($1, $2);
  $targettag = $ARGV[0];
  $basetag = $tagroot . ($target-1) if $target > 1;
} elsif (@ARGV == 2) {
  ($basetag, $targettag) = @ARGV;
} else {
  die "this script wants 1 or 2 arguments";
}


## base of the command

our $basecmd = 'cvs -f -z4 upd -dP ';
$basecmd .= '-j ' . $basetag . ' ' if defined $basetag;
$basecmd .= '-j ' . $targettag . ' ';

## do merge

foreach my $cmd ($basecmd . '-kk -l',
		 $basecmd . join (' ', @binarydirs),
		 $basecmd . '-kk ' . join (' ', @nonbindirs),
		) {
  print "** Now running $cmd\n";
  system ($cmd) and die "partial merge failed: $!";
}