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
36 =item debian/I<package>.compress
38 If this file exists, the default files are not compressed. Instead, the
39 file is ran as a shell script, and all filenames that the shell script
40 outputs will be compressed. The shell script will be run from inside the
41 package build directory. Note though that using -X is a much better idea in
42 general; you should only use a debian/package.compress file if you really
49 =item B<-X>I<item>, B<--exclude=>I<item>
51 Exclude files that contain "item" anywhere in their filename from being
52 compressed. For example, -X.tiff will exclude tiff files from compression.
53 You may use this option multiple times to build up a list of things to
54 exclude. You can accomplish the same thing by using a debian/compress file,
59 Compress all files specified by command line parameters in ALL packages
64 Add these files to the list of files to compress.
70 Debian policy, version 3.0
76 foreach my $package (@{$dh{DOPACKAGES}}) {
77 my $tmp=tmpdir($package);
78 my $compress=pkgfile($package,"compress");
80 # Run the file name gathering commands from within the directory
81 # structure that will be effected.
83 verbose_print("cd $tmp");
84 chdir($tmp) || error("Can't cd to $tmp: $!");
86 # Figure out what files to compress.
88 # First of all, deal with any files specified right on the command line.
89 if (($package eq $dh{FIRSTPACKAGE} || $dh{PARAMS_ALL}) && @ARGV) {
93 # The config file is a sh script that outputs the files to be compressed
94 # (typically using find).
95 push @files, split(/\n/,`sh $olddir/$compress 2>/dev/null`);
98 # Note that all the excludes of odd things like _z
99 # are because gzip refuses to compress such files, assumming
100 # they are zip files. I looked at the gzip source to get the
101 # complete list of such extensions: ".gz", ".z", ".taz",
102 # ".tgz", "-gz", "-z", "_z"
103 push @files, split(/\n/,`
104 find usr/info usr/share/info usr/man usr/share/man usr/X11*/man -type f ! -name "*.gz" 2>/dev/null || true;
105 find usr/share/doc -type f \\( -size +4k -or -name "changelog*" -or -name "NEWS*" \\) \\
106 \\( -name changelog.html -or ! -iname "*.htm*" \\) \\
107 ! -iname "*.gif" ! -iname "*.png" ! -iname "*.jpg" \\
108 ! -iname "*.jpeg" ! -iname "*.gz" ! -iname "*.taz" \\
109 ! -iname "*.tgz" ! -iname "*.z" ! -iname "*.bz2" \\
110 ! -iname "*-gz" ! -iname "*-z" ! -iname "*_z" \\
111 ! -iname "*.jar" ! -iname "*.zip" ! -iname "*.css" \\
112 ! -iname "*.svg" ! -iname "*.svgz" \\
113 ! -name "index.sgml" \\
114 ! -name "copyright" 2>/dev/null || true;
115 find usr/X11R6/lib/X11/fonts usr/share/fonts/X11 -type f -name "*.pcf" 2>/dev/null || true;
119 # Exclude files from compression.
120 if (@files && defined($dh{EXCLUDE}) && $dh{EXCLUDE}) {
124 foreach my $x (@{$dh{EXCLUDE}}) {
135 # Look for files with hard links. If we are going to compress both,
136 # we can preserve the hard link across the compression and save
142 my ($dev, $inode, undef, $nlink)=stat($_);
144 if (! $seen{"$inode.$dev"}) {
145 $seen{"$inode.$dev"}=$_;
149 # This is a hardlink.
150 $hardlinks{$_}=$seen{"$inode.$dev"};
159 # Make executables not be anymore.
160 xargs(\@f,"chmod","a-x");
162 xargs(\@f,"gzip","-9nf");
165 # Now change over any files we can that used to be hard links so
167 foreach (keys %hardlinks) {
169 doit("rm","-f","$_");
171 doit("ln","$hardlinks{$_}.gz","$_.gz");
174 verbose_print("cd '$olddir'");
177 # Fix up symlinks that were pointing to the uncompressed files.
178 my %links = map { chomp; $_ => 1 } `find $tmp -type l`;
180 # Keep looping through looking for broken links until no more
181 # changes are made. This is done in case there are links pointing
182 # to links, pointing to compressed files.
185 foreach my $link (keys %links) {
186 my ($directory) = $link =~ m:(.*)/:;
187 my $linkval = readlink($link);
188 if (! -e "$directory/$linkval" && -e "$directory/$linkval.gz") {
189 doit("rm","-f",$link);
190 doit("ln","-sf","$linkval.gz","$link.gz");
191 delete $links{$link};
202 This program is a part of debhelper.
206 Joey Hess <joeyh@debian.org>