5 dh_compress - compress files and fix symlinks in package build directories
11 use Debian::Debhelper::Dh_Lib;
15 B<dh_compress> [S<I<debhelper options>>] [B<-X>I<item>] [B<-A>] [S<I<file ...>>]
19 dh_compress is a debhelper program that is responsible for compressing
20 the files in package build directories, and makes sure that any symlinks
21 that pointed to the files before they were compressed are updated to point
24 By default, dh_compress compresses files that debian policy mandates should
25 be compressed, namely all files in usr/share/info, usr/share/man,
26 usr/X11R6/man, files in usr/share/doc that are larger than 4k in size,
27 (except the copyright file, .html and .css files, image files, and files
28 that appear to be already compressed based on their extensions), and all
29 changelog files. Plus PCF fonts underneath usr/X11R6/lib/X11/fonts/ and
32 If a debian/package.compress file exists, the default files are not
33 compressed. Instead, the debian/packages.compress is ran as a shell
34 script, and all filenames that the shell script outputs will be compressed.
35 The shell script will be run from inside the package build directory. Note
36 though that using -X is a much better idea in general; you should only use a
37 debian/package.compress file if you really need to.
43 =item B<-X>I<item>, B<--exclude=>I<item>
45 Exclude files that contain "item" anywhere in their filename from being
46 compressed. For example, -X.tiff will exclude tiff files from compression.
47 You may use this option multiple times to build up a list of things to
48 exclude. You can accomplish the same thing by using a debian/compress file,
53 Compress all files specified by command line parameters in ALL packages
58 Add these files to the list of files to compress.
64 Debian policy, version 3.0
70 foreach my $package (@{$dh{DOPACKAGES}}) {
71 my $tmp=tmpdir($package);
72 my $compress=pkgfile($package,"compress");
74 # Run the file name gathering commands from within the directory
75 # structure that will be effected.
77 verbose_print("cd $tmp");
78 chdir($tmp) || error("Can't cd to $tmp: $!");
80 # Figure out what files to compress.
82 # First of all, deal with any files specified right on the command line.
83 if (($package eq $dh{FIRSTPACKAGE} || $dh{PARAMS_ALL}) && @ARGV) {
87 # The config file is a sh script that outputs the files to be compressed
88 # (typically using find).
89 push @files, split(/\n/,`sh $olddir/$compress 2>/dev/null`);
92 # Note that all the excludes of odd things like _z
93 # are because gzip refuses to compress such files, assumming
94 # they are zip files. I looked at the gzip source to get the
95 # complete list of such extensions: ".gz", ".z", ".taz",
96 # ".tgz", "-gz", "-z", "_z"
97 push @files, split(/\n/,`
98 find usr/info usr/share/info usr/man usr/share/man usr/X11*/man -type f ! -name "*.gz" 2>/dev/null || true;
99 find usr/share/doc -type f \\( -size +4k -or -name "changelog*" -or -name "NEWS*" \\) \\
100 \\( -name changelog.html -or ! -iname "*.htm*" \\) \\
101 ! -iname "*.gif" ! -iname "*.png" ! -iname "*.jpg" \\
102 ! -iname "*.jpeg" ! -iname "*.gz" ! -iname "*.taz" \\
103 ! -iname "*.tgz" ! -iname "*.z" ! -iname "*.bz2" \\
104 ! -iname "*-gz" ! -iname "*-z" ! -iname "*_z" \\
105 ! -iname "*.jar" ! -iname "*.zip" ! -iname "*.css" \\
106 ! -iname "*.svg" ! -iname "*.svgz" \\
107 ! -name "index.sgml" \\
108 ! -name "copyright" 2>/dev/null || true;
109 find usr/X11R6/lib/X11/fonts usr/share/fonts/X11 -type f -name "*.pcf" 2>/dev/null || true;
113 # Exclude files from compression.
114 if (@files && defined($dh{EXCLUDE}) && $dh{EXCLUDE}) {
118 foreach my $x (@{$dh{EXCLUDE}}) {
129 # Look for files with hard links. If we are going to compress both,
130 # we can preserve the hard link across the compression and save
136 my ($dev, $inode, undef, $nlink)=stat($_);
138 if (! $seen{"$inode.$dev"}) {
139 $seen{"$inode.$dev"}=$_;
143 # This is a hardlink.
144 $hardlinks{$_}=$seen{"$inode.$dev"};
153 # Make executables not be anymore.
154 xargs(\@f,"chmod","a-x");
156 xargs(\@f,"gzip","-9nf");
159 # Now change over any files we can that used to be hard links so
161 foreach (keys %hardlinks) {
163 doit("rm","-f","$_");
165 doit("ln","$hardlinks{$_}.gz","$_.gz");
168 verbose_print("cd '$olddir'");
171 # Fix up symlinks that were pointing to the uncompressed files.
172 my %links = map { chomp; $_ => 1 } `find $tmp -type l`;
174 # Keep looping through looking for broken links until no more
175 # changes are made. This is done in case there are links pointing
176 # to links, pointing to compressed files.
179 foreach my $link (keys %links) {
180 my ($directory) = $link =~ m:(.*)/:;
181 my $linkval = readlink($link);
182 if (! -e "$directory/$linkval" && -e "$directory/$linkval.gz") {
183 doit("rm","-f",$link);
184 doit("ln","-sf","$linkval.gz","$link.gz");
185 delete $links{$link};
196 This program is a part of debhelper.
200 Joey Hess <joeyh@debian.org>