xref: /linux/scripts/setlocalversion (revision aaebf4332018980fef4e601d1b5a6e52dd9e9ae4)
1*aaebf433SRyan Anderson#!/usr/bin/perl
2*aaebf433SRyan Anderson# Copyright 2004 - Ryan Anderson <ryan@michonline.com>  GPL v2
3*aaebf433SRyan Anderson
4*aaebf433SRyan Andersonuse strict;
5*aaebf433SRyan Andersonuse warnings;
6*aaebf433SRyan Andersonuse Digest::MD5;
7*aaebf433SRyan Andersonrequire 5.006;
8*aaebf433SRyan Anderson
9*aaebf433SRyan Andersonif (@ARGV != 1) {
10*aaebf433SRyan Anderson	print <<EOT;
11*aaebf433SRyan AndersonUsage: setlocalversion <srctree>
12*aaebf433SRyan AndersonEOT
13*aaebf433SRyan Anderson	exit(1);
14*aaebf433SRyan Anderson}
15*aaebf433SRyan Anderson
16*aaebf433SRyan Andersonmy ($srctree) = @ARGV;
17*aaebf433SRyan Andersonchdir($srctree);
18*aaebf433SRyan Anderson
19*aaebf433SRyan Andersonmy @LOCALVERSIONS = ();
20*aaebf433SRyan Anderson
21*aaebf433SRyan Anderson# We are going to use the following commands to try and determine if this
22*aaebf433SRyan Anderson# repository is at a Version boundary (i.e, 2.6.10 vs 2.6.10 + some patches) We
23*aaebf433SRyan Anderson# currently assume that all meaningful version boundaries are marked by a tag.
24*aaebf433SRyan Anderson# We don't care what the tag is, just that something exists.
25*aaebf433SRyan Anderson
26*aaebf433SRyan Anderson# Git/Cogito store the top-of-tree "commit" in .git/HEAD
27*aaebf433SRyan Anderson# A list of known tags sits in .git/refs/tags/
28*aaebf433SRyan Anderson#
29*aaebf433SRyan Anderson# The simple trick here is to just compare the two of these, and if we get a
30*aaebf433SRyan Anderson# match, return nothing, otherwise, return a subset of the SHA-1 hash in
31*aaebf433SRyan Anderson# .git/HEAD
32*aaebf433SRyan Anderson
33*aaebf433SRyan Andersonsub do_git_checks {
34*aaebf433SRyan Anderson	open(H,"<.git/HEAD") or return;
35*aaebf433SRyan Anderson	my $head = <H>;
36*aaebf433SRyan Anderson	chomp $head;
37*aaebf433SRyan Anderson	close(H);
38*aaebf433SRyan Anderson
39*aaebf433SRyan Anderson	opendir(D,".git/refs/tags") or return;
40*aaebf433SRyan Anderson	foreach my $tagfile (grep !/^\.{1,2}$/, readdir(D)) {
41*aaebf433SRyan Anderson		open(F,"<.git/refs/tags/" . $tagfile) or return;
42*aaebf433SRyan Anderson		my $tag = <F>;
43*aaebf433SRyan Anderson		chomp $tag;
44*aaebf433SRyan Anderson		close(F);
45*aaebf433SRyan Anderson		return if ($tag eq $head);
46*aaebf433SRyan Anderson	}
47*aaebf433SRyan Anderson	closedir(D);
48*aaebf433SRyan Anderson
49*aaebf433SRyan Anderson	push @LOCALVERSIONS, "g" . substr($head,0,8);
50*aaebf433SRyan Anderson}
51*aaebf433SRyan Anderson
52*aaebf433SRyan Andersonif ( -d ".git") {
53*aaebf433SRyan Anderson	do_git_checks();
54*aaebf433SRyan Anderson}
55*aaebf433SRyan Anderson
56*aaebf433SRyan Andersonprintf "-%s\n", join("-",@LOCALVERSIONS) if (scalar @LOCALVERSIONS > 0);
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