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, and files that appear to be
28 already compressed based on their extensions), and all changelog files. Plus
29 PCF fonts underneath usr/X11R6/lib/X11/fonts/ and usr/share/fonts/X11/
31 If a debian/package.compress file exists, the default files are not
32 compressed. Instead, the debian/packages.compress is ran as a shell
33 script, and all filenames that the shell script outputs will be compressed.
34 The shell script will be run from inside the package build directory. Note
35 though that using -X is a much better idea in general; you should only use a
36 debian/package.compress file if you really need to.
42 =item B<-X>I<item>, B<--exclude=>I<item>
44 Exclude files that contain "item" anywhere in their filename from being
45 compressed. For example, -X.jpeg will exclude jpeg files from compression.
46 You may use this option multiple times to build up a list of things to
47 exclude. You can accomplish the same thing by using a debian/compress file,
52 Compress all files specified by command line parameters in ALL packages
57 Add these files to the list of files to compress.
63 Debian policy, version 3.0
69 foreach my $package (@{$dh{DOPACKAGES}}) {
70 my $tmp=tmpdir($package);
71 my $compress=pkgfile($package,"compress");
73 # Run the file name gathering commands from within the directory
74 # structure that will be effected.
76 verbose_print("cd $tmp");
77 chdir($tmp) || error("Can't cd to $tmp: $!");
79 # Figure out what files to compress.
81 # First of all, deal with any files specified right on the command line.
82 if (($package eq $dh{FIRSTPACKAGE} || $dh{PARAMS_ALL}) && @ARGV) {
86 # The config file is a sh script that outputs the files to be compressed
87 # (typically using find).
88 push @files, split(/\n/,`sh $olddir/$compress 2>/dev/null`);
91 # Note that all the excludes of odd things like _z
92 # are because gzip refuses to compress such files, assumming
93 # they are zip files. I looked at the gzip source to get the
94 # complete list of such extensions: ".gz", ".z", ".taz",
95 # ".tgz", "-gz", "-z", "_z"
96 push @files, split(/\n/,`
97 find usr/info usr/share/info usr/man usr/share/man usr/X11*/man -type f ! -name "*.gz" 2>/dev/null || true;
98 find usr/share/doc -type f \\( -size +4k -or -name "changelog*" -or -name "NEWS*" \\) \\
99 \\( -name changelog.html -or ! -iname "*.htm*" \\) \\
100 ! -iname "*.gif" ! -iname "*.png" ! -iname "*.jpg" \\
101 ! -iname "*.jpeg" ! -iname "*.gz" ! -iname "*.taz" \\
102 ! -iname "*.tgz" ! -iname "*.z" ! -iname "*.bz2" \\
103 ! -iname "*-gz" ! -iname "*-z" ! -iname "*_z" \\
104 ! -iname "*.jar" ! -iname "*.zip" ! -iname "*.css" \\
105 ! -name "index.sgml" \\
106 ! -name "copyright" 2>/dev/null || true;
107 find usr/X11R6/lib/X11/fonts usr/share/fonts/X11 -type f -name "*.pcf" 2>/dev/null || true;
111 # Exclude files from compression.
112 if (@files && defined($dh{EXCLUDE}) && $dh{EXCLUDE}) {
116 foreach my $x (@{$dh{EXCLUDE}}) {
127 # Look for files with hard links. If we are going to compress both,
128 # we can preserve the hard link across the compression and save
134 my ($dev, $inode, undef, $nlink)=stat($_);
136 if (! $seen{"$inode.$dev"}) {
137 $seen{"$inode.$dev"}=$_;
141 # This is a hardlink.
142 $hardlinks{$_}=$seen{"$inode.$dev"};
151 # Make executables not be anymore.
152 xargs(\@f,"chmod","a-x");
154 xargs(\@f,"gzip","-9nf");
157 # Now change over any files we can that used to be hard links so
159 foreach (keys %hardlinks) {
161 doit("rm","-f","$_");
163 doit("ln","$hardlinks{$_}.gz","$_.gz");
166 verbose_print("cd '$olddir'");
169 # Fix up symlinks that were pointing to the uncompressed files.
170 my %links = map { chomp; $_ => 1 } `find $tmp -type l`;
172 # Keep looping through looking for broken links until no more
173 # changes are made. This is done in case there are links pointing
174 # to links, pointing to compressed files.
177 foreach my $link (keys %links) {
178 my ($directory) = $link =~ m:(.*)/:;
179 my $linkval = readlink($link);
180 if (! -e "$directory/$linkval" && -e "$directory/$linkval.gz") {
181 doit("rm","-f",$link);
182 doit("ln","-sf","$linkval.gz","$link.gz");
183 delete $links{$link};
194 This program is a part of debhelper.
198 Joey Hess <joeyh@debian.org>