summaryrefslogtreecommitdiff
path: root/Dh_Lib.pm
blob: e74e8ccbcbb6a5ae06bd924e061b494970ab9f4b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
#!/usr/bin/perl -w
#
# Library functions for debhelper programs, perl version.
#
# Joey Hess, GPL copyright 1997, 1998.

package Dh_Lib;
use strict;

use Exporter;
use vars qw(@ISA @EXPORT %dh);
@ISA=qw(Exporter);
@EXPORT=qw(&init &doit &complex_doit &verbose_print &error &warning &tmpdir
	    &pkgfile &pkgext &isnative &autoscript &filearray &GetPackages
	    &xargs
	    %dh);

my $max_compat=2;

sub init {
	# If DH_OPTIONS is set, prepend it @ARGV.
	if (defined($ENV{DH_OPTIONS})) {
		unshift @ARGV,split(/\s+/,$ENV{DH_OPTIONS});
	}

	# Check to see if an argument on the command line starts with a dash.
	# if so, we need to pass this off to the resource intensive 
	# Getopt::Long, which I'd prefer to avoid loading at all if possible.
	my $parseopt=undef;
	my $arg;
	foreach $arg (@ARGV) {
		if ($arg=~m/^-/) {
			$parseopt=1;
			last;
		}       
	}
	if ($parseopt) {
		eval "use Dh_Getopt";
		error($!) if $@;
		%dh=Dh_Getopt::parseopts();
	}

	# Check to see if DH_VERBOSE environment variable was set, if so,
	# make sure verbose is on.
	if (defined $ENV{DH_VERBOSE} && $ENV{DH_VERBOSE} ne "") {
		$dh{VERBOSE}=1;
	}

	# Check to see if DH_NO_ACT environment variable was set, if so, 
	# make sure no act mode is on.
	if (defined $ENV{DH_NO_ACT} && $ENV{DH_NO_ACT} ne "") {
		$dh{NO_ACT}=1;
	}

	# Get the name of the main binary package (first one listed in
	# debian/control).
	my @allpackages=GetPackages();
	$dh{MAINPACKAGE}=$allpackages[0];

	# Check if packages to build have been specified, if not, fall back to
	# the default, doing them all.
	if (! defined $dh{DOPACKAGES} || ! @{$dh{DOPACKAGES}}) {
		if ($dh{DOINDEP} || $dh{DOARCH} || $dh{DOSAME}) {
			# User specified that all arch (in)dep package be 
			# built, and there are none of that type.
			error("I have no package to act on");
		}
		push @{$dh{DOPACKAGES}},@allpackages;
	}

	# Check to see if -P was specified. If so, we can only act on a single
	# package.
	if ($dh{TMPDIR} && $#{$dh{DOPACKAGES}} > 0) {
		error("-P was specified, but multiple packages would be acted on (".join(",",@{$dh{DOPACKAGES}}).").");
	}

	# Figure out which package is the first one we were instructed to build.
	# This package gets special treatement: files and directories specified on
	# the command line may affect it.
	$dh{FIRSTPACKAGE}=${$dh{DOPACKAGES}}[0];

	# Split the U_PARAMS up into an array.
	my $u=$dh{U_PARAMS};
	undef $dh{U_PARAMS};
	if (defined $u) {
		push @{$dh{U_PARAMS}}, split(/\s+/,$u);
	}
}

# Escapes out shell metacharacters in a word of shell script.
sub escape_shell { my $word=shift;
	# This list is from _Unix in a Nutshell_. (except '#')
	$word=~s/([\s!"\$()*+#;<>?@\[\]\\`|~])/\\$1/g;
	return $word;
}

# Run a command, and display the command to stdout if verbose mode is on.
# All commands that modifiy files in $TMP should be ran via this 
# function.
#
# Note that this cannot handle complex commands, especially anything
# involving redirection. Use complex_doit instead.
sub doit {
	verbose_print(join(" ",map { escape_shell($_) } @_));
	
	if (! $dh{NO_ACT}) {
		system(@_) == 0
			|| error("command returned error code");
		
	}
}

# Run a command and display the command to stdout if verbose mode is on.
# Use doit() if you can, instead of this function, because this function
# forks a shell. However, this function can handle more complicated stuff
# like redirection.
sub complex_doit {
	verbose_print(join(" ",@_));
	
	if (! $dh{NO_ACT}) {
		# The join makes system get a scalar so it forks off a shell.
		system(join(" ",@_)) == 0
			|| error("command returned error code");
	}			
}

# Run a command that may have a huge number of arguments, like xargs does.
# Pass in a reference to an array containing the arguments, and then other
# parameters that are the command and any parameters that should be passed to
# it each time.
sub xargs {
	my $args=shift;

        # The kernel can accept command lines up to 20k worth of characters.
	my $command_max=20000;

	# Figure out length of static portion of command.
	my $static_length=0;
	foreach (@_) {
		$static_length+=length($_)+1;
	}
	
	my @collect=();
	my $length=$static_length;
	foreach (@$args) {
		if (length($_) + 1 + $static_length > $command_max) {
			error("This command is greater than the maximum command size allowed by the kernel, and cannot be split up further. What on earth are you doing? \"@_ $_\"");
		}
		$length+=length($_) + 1;
		if ($length < $command_max) {
			push @collect, $_;
		}
		else {
			doit(@_,@collect) if $#collect > -1;
			@collect=();
			$length=$static_length;
		}
	}
	doit(@_,@collect) if $#collect > -1;
}

# Print something if the verbose flag is on.
sub verbose_print { my $message=shift;
	if ($dh{VERBOSE}) {
		print "\t$message\n";
	}
}

# Output an error message and exit.
sub error { my $message=shift;
	warning($message);
	exit 1;
}

# Output a warning.
sub warning { my $message=shift;
	print STDERR basename($0).": $message\n";
}

# Returns the basename of the argument passed to it.
sub basename { my $fn=shift;
	$fn=~s:^.*/(.*?)$:$1:;
	return $fn;
}

# Returns the directory name of the argument passed to it.
sub dirname { my $fn=shift;
	$fn=~s:^(.*)/.*?$:$1:;
	return $fn;
}

# Pass in a number, will return true iff the current compatability level
# is equal to that number.
sub compat {
	my $num=shift;
	
	my $c=1;
	if (defined $ENV{DH_COMPAT}) {
		$c=$ENV{DH_COMPAT};
	}

	if ($c > $max_compat) {
		error("Sorry, but $max_compat is the highest compatability level of debhelper currently supported.");
	}

	return ($c == $num);
}

# Pass it a name of a binary package, it returns the name of the tmp dir to
# use, for that package.
sub tmpdir { my $package=shift;
	if ($dh{TMPDIR}) {
		return $dh{TMPDIR};
	}
	elsif (compat(1) && $package eq $dh{MAINPACKAGE}) {
		# This is for back-compatability with the debian/tmp tradition.
		return "debian/tmp";
	}
	else {
		return "debian/$package";
	}
}

# Pass this the name of a binary package, and the name of the file wanted
# for the package, and it will return the actual filename to use. For
# example if the package is foo, and the file is somefile, it will look for
# debian/somefile, and if found return that, otherwise, if the package is
# the main package, it will look for debian/foo, and if found, return that.
# Failing that, it will return nothing.
sub pkgfile { my $package=shift; my $filename=shift;
	if (-f "debian/$package.$filename") {
		return "debian/$package.$filename";
	}
	elsif ($package eq $dh{MAINPACKAGE} && -f "debian/$filename") {
		return "debian/$filename";
	}
	return "";
}

# Pass it a name of a binary package, it returns the name to prefix to files
# in debian for this package.
sub pkgext { my $package=shift;
	if ($package ne $dh{MAINPACKAGE}) {
		return "$package.";
	}
	return "";
}

# Returns 1 if the package is a native debian package, null otherwise.
# As a side effect, sets $dh{VERSION} to the version of this package.
{
	# Caches return code so it only needs to run dpkg-parsechangelog once.
	my %isnative_cache;
	
	sub isnative { my $package=shift;
		if (! defined $isnative_cache{$package}) {
			# Make sure we look at the correct changelog.
			my $isnative_changelog=pkgfile($package,"changelog");
			if (! $isnative_changelog) {
				$isnative_changelog="debian/changelog";
			}

			# Get the package version.
			my $version=`dpkg-parsechangelog -l$isnative_changelog`;
			($dh{VERSION})=$version=~m/Version: (.*)/m;

			# Is this a native Debian package?
			if ($dh{VERSION}=~m/.*-/) {
				$isnative_cache{$package}=0;
			}
			else {
				$isnative_cache{$package}=1;
			}
		}
	
		return $isnative_cache{$package};
	}
}

# Automatically add a shell script snippet to a debian script.
# Only works if the script has #DEBHELPER# in it.
#
# Parameters:
# 1: package
# 2: script to add to
# 3: filename of snippet
# 4: sed to run on the snippet. Ie, s/#PACKAGE#/$PACKAGE/
sub autoscript { my $package=shift; my $script=shift; my $filename=shift; my $sed=shift || "";
	# This is the file we will append to.
	my $outfile="debian/".pkgext($package)."$script.debhelper";

	# Figure out what shell script snippet to use.
	my $infile;
	if (defined($ENV{DH_AUTOSCRIPTDIR}) && 
	    -e "$ENV{DH_AUTOSCRIPTDIR}/$filename") {
		$infile="$ENV{DH_AUTOSCRIPTDIR}/$filename";
	}
	else {
		if (-e "/usr/share/debhelper/autoscripts/$filename") {
			$infile="/usr/share/debhelper/autoscripts/$filename";
		}
		else {
			error("/usr/share/debhelper/autoscripts/$filename does not exist");
		}
	}

	# TODO: do this in perl, perhaps?
	complex_doit("echo \"# Automatically added by ".basename($0)."\">> $outfile");
	complex_doit("sed \"$sed\" $infile >> $outfile");
	complex_doit("echo '# End automatically added section' >> $outfile");
}

# Reads in the specified file, one word at a time, and returns an array of
# the result.
sub filearray { my $file=shift;
	my @ret;
	open (DH_FARRAY_IN,"<$file") || error("cannot read $file: $1");
	while (<DH_FARRAY_IN>) {
		push @ret,split(' ',$_);
	}
	close DH_FARRAY_IN;
	
	return @ret;
}

# Returns a list of packages in the control file.
# Must pass "arch" or "indep" or "same" to specify arch-dependant or
# -independant or same arch packages. If nothing is specified, returns all
# packages.
sub GetPackages { my $type=shift;
	$type="" if ! defined $type;
	
	# Look up the build arch if we need to.
	my$buildarch='';
	if ($type eq 'same') {
		$buildarch=`dpkg --print-architecture` || error($!);
		chomp $buildarch;
	}

	my $package="";
	my $arch="";
	my @list=();
	open (CONTROL,"<debian/control") ||
		error("cannot read debian/control: $!\n");
	while (<CONTROL>) {
		chomp;
		s/\s+$//;
		if (/^Package:\s+(.*)/) {
			$package=$1;
		}
		if (/^Architecture:\s+(.*)/) {
			$arch=$1;
		}
		if (!$_ or eof) { # end of stanza.
			if ($package &&
			    (($type eq 'indep' && $arch eq 'all') ||
			     ($type eq 'arch' && $arch ne 'all') ||
			     ($type eq 'same' && ($arch eq 'any' || $arch =~ /\b$buildarch\b/)) ||
			     ! $type)) {
				push @list, $package;
				$package="";
				$arch="";
			}
		}
	}
	close CONTROL;

	return @list;
}

1