summaryrefslogtreecommitdiffstats
path: root/lib/Debian/Debhelper/Buildsystem.pm
blob: 795f3d3d77922f2ab7d44721e0992cf5018a64b7 (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
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
# Defines debhelper build system class interface and implementation
# of common functionality.
#
# Copyright: © 2008-2009 Modestas Vainius
# License: GPL-2+

package Debian::Debhelper::Buildsystem;

use strict;
use warnings;
use Cwd ();
use File::Spec;
use Debian::Debhelper::Dh_Lib;

# Build system name. Defaults to the last component of the class
# name. Do not override this method unless you know what you are
# doing.
sub NAME {
	my ($this) = @_;
	my $class = ref($this);
	my $target_name;
	if ($class) {
		# Do not assume that the target buildsystem has been provided.
		# NAME could be called during an error in the constructor.
		if ($this->IS_GENERATOR_BUILD_SYSTEM and $this->get_targetbuildsystem) {
			$target_name = $this->get_targetbuildsystem->NAME;
		}
	} else {
		$class = $this;
	}
	if ($class =~ m/^.+::([^:]+)$/) {
		my $name = $1;
		return "${name}+${target_name}" if defined($target_name);
		return $name;
	}
	else {
		error("Invalid build system class name: $class");
	}
}

# Description of the build system to be shown to the users.
sub DESCRIPTION {
	error("class lacking a DESCRIPTION");
}

# Default build directory. Can be overridden in the derived
# class if really needed.
sub DEFAULT_BUILD_DIRECTORY {
	"obj-" . dpkg_architecture_value("DEB_HOST_GNU_TYPE");
}

# Return 1 if the build system generator
sub IS_GENERATOR_BUILD_SYSTEM {
	return 0;
}

# Generator build-systems only
# The name of the supported target systems.  The first one is
# assumed to be the default if DEFAULT_TARGET_BUILD_SYSTEM is
# not overridden.
sub SUPPORTED_TARGET_BUILD_SYSTEMS {
	error("class lacking SUPPORTED_TARGET_BUILD_SYSTEMS");
}

# Generator build-systems only
# Name of default target build system if target is unspecified
#  (e.g. --buildsystem=cmake instead of cmake+makefile).
sub DEFAULT_TARGET_BUILD_SYSTEM {
	my ($this) = @_;
	my @targets = $this->SUPPORTED_TARGET_BUILD_SYSTEMS;
	# Assume they are listed in order.
	return $targets[0];
}

# For regular build systems, the same as DESCRIPTION
# For generator based build systems, the DESCRIPTION of the generator build
# system + the target build system.  Do not override this method unless you
# know what you are doing.
sub FULL_DESCRIPTION {
	my ($this) = @_;
	my $description = $this->DESCRIPTION;
	return $description if not exists($this->{'targetbuildsystem'});
	my $target_build_system = $this->{'targetbuildsystem'};
	return $description if not defined($target_build_system);
	my $target_desc = $target_build_system->FULL_DESCRIPTION;
	return "${description} combined with ${target_desc}";
}

# Constructs a new build system object. Named parameters:
# - sourcedir-     specifies source directory (relative to the current (top)
#                  directory) where the sources to be built live. If not
#                  specified or empty, defaults to the current directory.
# - builddir -     specifies build directory to use. Path is relative to the
#                  current (top) directory. If undef or empty,
#                  DEFAULT_BUILD_DIRECTORY directory will be used.
# - parallel -     max number of parallel processes to be spawned for building
#                  sources (-1 = unlimited; 1 = no parallel)
# - targetbuildsystem -     The target build system for generator based build
#                           systems.  Only set for generator build systems.
# Derived class can override the constructor to initialize common object
# parameters. Do NOT use constructor to execute commands or otherwise
# configure/setup build environment. There is absolutely no guarantee the
# constructed object will be used to build something. Use pre_building_step(),
# $build_step() or post_building_step() methods for this.
sub new {
	my ($class, %opts)=@_;

	my $this = bless({ sourcedir => '.',
	                   builddir => undef,
	                   parallel => undef,
	                   cwd => Cwd::getcwd() }, $class);

	# Setup the target buildsystem early, so e.g. _set_builddir also
	# applies to the target build system.  Useful if the generator
	# and target does not agree on (e.g.) the default build dir.
	my $target_bs_name;
	if (exists $opts{targetbuildsystem}) {
		$target_bs_name = $opts{targetbuildsystem};
	}

	$target_bs_name //= $this->DEFAULT_TARGET_BUILD_SYSTEM if $this->IS_GENERATOR_BUILD_SYSTEM;

	if (defined($target_bs_name)) {
		my %target_opts = %opts;
		# Let the target know it is used as a target build system.
		# E.g. the makefile has special cases based on whether it is
		# the main or a target build system.
		delete($target_opts{'targetbuildsystem'});
		$target_opts{'_is_targetbuildsystem'} = 1;
		my $target_system =_create_buildsystem_instance($target_bs_name, 1, %target_opts);
		$this->set_targetbuildsystem($target_system);
	}

	$this->{'_is_targetbuildsystem'} = $opts{'_is_targetbuildsystem'}
	  if exists($opts{'_is_targetbuildsystem'});

	if (exists $opts{sourcedir}) {
		# Get relative sourcedir abs_path (without symlinks)
		my $abspath = Cwd::abs_path($opts{sourcedir});
		if (! -d $abspath || $abspath !~ /^\Q$this->{cwd}\E/) {
			error("invalid or non-existing path to the source directory: ".$opts{sourcedir});
		}
		$this->{sourcedir} = File::Spec->abs2rel($abspath, $this->{cwd});
	}
	if (exists $opts{builddir}) {
		$this->_set_builddir($opts{builddir});
	}
	if (defined $opts{parallel}) {
		$this->{parallel} = $opts{parallel};
	}

	return $this;
}

# Private method to set a build directory. If undef, use default.
# Do $this->{builddir} = undef or pass $this->get_sourcedir() to
# unset the build directory.
sub _set_builddir {
	my $this=shift;
	my $builddir=shift || $this->DEFAULT_BUILD_DIRECTORY;

	if (defined $builddir) {
		$builddir = $this->canonpath($builddir); # Canonicalize

		# Sanitize $builddir
		if ($builddir =~ m#^\.\./#) {
			# We can't handle those as relative. Make them absolute
			$builddir = File::Spec->catdir($this->{cwd}, $builddir);
		}
		elsif ($builddir =~ /\Q$this->{cwd}\E/) {
			$builddir = File::Spec->abs2rel($builddir, $this->{cwd});
		}

		# If build directory ends up the same as source directory, drop it
		if ($builddir eq $this->get_sourcedir()) {
			$builddir = undef;
		}
	}
	$this->{builddir} = $builddir;
	# Use get as guard because this method is (also) called from the
	# constructor before the target build system is setup.
	if ($this->get_targetbuildsystem) {
		$this->get_targetbuildsystem->{builddir} = $builddir;
	};
	return $builddir;
}

sub set_targetbuildsystem {
	my ($this, $target_system) = @_;
	my $ok = 0;
	my $target_bs_name = $target_system->NAME;
	if (not $this->IS_GENERATOR_BUILD_SYSTEM) {
		my $name = $this->NAME;
		error("Cannot set a target build system: Buildsystem ${name} is not a generator build system");
	}
	for my $supported_bs_name ($this->SUPPORTED_TARGET_BUILD_SYSTEMS) {
		if ($supported_bs_name eq $target_bs_name) {
			$ok = 1;
			last;
		}
	}
	if (not $ok) {
		my $name = $this->NAME;
		error("Buildsystem ${name} does not support ${target_bs_name} as target build system.");
	}
	$this->{'targetbuildsystem'} = $target_system
}

sub _is_targetbuildsystem {
	my ($this) = @_;
	return 0 if not exists($this->{'_is_targetbuildsystem'});
	return $this->{'_is_targetbuildsystem'};
}

# Returns the target build system if it is provided
sub get_targetbuildsystem {
	my $this = shift;
	return if not exists($this->{'targetbuildsystem'});
	return $this->{'targetbuildsystem'};
}

# This instance method is called to check if the build system is able
# to build a source package. It will be called during the build
# system auto-selection process, inside the root directory of the debian
# source package. The current build step is passed as an argument.
# Return 0 if the source is not buildable, or a positive integer
# otherwise.
#
# Generally, it is enough to look for invariant unique build system
# files shipped with clean source to determine if the source might
# be buildable or not. However, if the build system is derived from
# another other auto-buildable build system, this method
# may also check if the source has already been built with this build
# system partially by looking for temporary files or other common
# results the build system produces during the build process. The
# latter checks must be unique to the current build system and must
# be very unlikely to be true for either its parent or other build
# systems. If it is determined that the source has already built
# partially with this build system, the value returned must be
# greater than the one of the SUPER call.
sub check_auto_buildable {
	my $this=shift;
	my ($step)=@_;
	return 0;
}

# Derived class can call this method in its constructor
# to enforce in source building even if the user requested otherwise.
sub enforce_in_source_building {
	my $this=shift;
	if ($this->get_builddir()) {
		$this->{warn_insource} = 1;
		$this->{builddir} = undef;
	}
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->enforce_in_source_building(@_);
		# Only warn in one build system.
		delete($this->{warn_insource});
	}
}

# Derived class can call this method in its constructor to *prefer*
# out of source building. Unless build directory has already been
# specified building will proceed in the DEFAULT_BUILD_DIRECTORY or
# the one specified in the 'builddir' named parameter (which may
# match the source directory). Typically you should pass @_ from
# the constructor to this call.
sub prefer_out_of_source_building {
	my $this=shift;
	my %args=@_;
	if (!defined $this->get_builddir()) {
		if (!$this->_set_builddir($args{builddir}) && !$args{builddir}) {
			# If we are here, DEFAULT_BUILD_DIRECTORY matches
			# the source directory, building might fail.
			error("default build directory is the same as the source directory." .
			      " Please specify a custom build directory");
		}
		if ($this->IS_GENERATOR_BUILD_SYSTEM) {
			$this->get_targetbuildsystem->prefer_out_of_source_building(@_);
		}
	}
}

# Enhanced version of File::Spec::canonpath. It collapses ..
# too so it may return invalid path if symlinks are involved.
# On the other hand, it does not need for the path to exist.
sub canonpath {
	my ($this, $path)=@_;
	my @canon;
	my $back=0;
	foreach my $comp (split(m%/+%, $path)) {
		if ($comp eq '.') {
			next;
		}
		elsif ($comp eq '..') {
			if (@canon > 0) { pop @canon; }  else { $back++; }
		}
		else {
			push @canon, $comp;
		}
	}
	return (@canon + $back > 0) ? join('/', ('..')x$back, @canon) : '.';
}

# Given both $path and $base are relative to the $root, converts and
# returns path of $path being relative to the $base. If either $path or
# $base is absolute, returns another $path (converted to) absolute.
sub _rel2rel {
	my ($this, $path, $base, $root)=@_;
	$root = $this->{cwd} unless defined $root;

	if (File::Spec->file_name_is_absolute($path)) {
		return $path;
	}
	elsif (File::Spec->file_name_is_absolute($base)) {
		return File::Spec->rel2abs($path, $root);
	}
	else {
		return File::Spec->abs2rel(
			File::Spec->rel2abs($path, $root),
			File::Spec->rel2abs($base, $root)
		);
	}
}

# Get path to the source directory
# (relative to the current (top) directory)
sub get_sourcedir {
	my $this=shift;
	return $this->{sourcedir};
}

# Convert path relative to the source directory to the path relative
# to the current (top) directory.
sub get_sourcepath {
	my ($this, $path)=@_;
	return File::Spec->catfile($this->get_sourcedir(), $path);
}

# Get path to the build directory if it was specified
# (relative to the current (top) directory). undef if the same
# as the source directory.
sub get_builddir {
	my $this=shift;
	return $this->{builddir};
}

# Convert path that is relative to the build directory to the path
# that is relative to the current (top) directory.
# If $path is not specified, always returns build directory path
# relative to the current (top) directory regardless if builddir was
# specified or not.
sub get_buildpath {
	my ($this, $path)=@_;
	my $builddir = $this->get_builddir() || $this->get_sourcedir();
	if (defined $path) {
		return File::Spec->catfile($builddir, $path);
	}
	return $builddir;
}

# When given a relative path to the source directory, converts it
# to the path that is relative to the build directory. If $path is
# not given, returns a path to the source directory that is relative
# to the build directory.
sub get_source_rel2builddir {
	my $this=shift;
	my $path=shift;

	my $dir = '.';
	if ($this->get_builddir()) {
		$dir = $this->_rel2rel($this->get_sourcedir(), $this->get_builddir());
	}
	if (defined $path) {
		return File::Spec->catfile($dir, $path);
	}
	return $dir;
}

sub get_parallel {
	my $this=shift;
	return $this->{parallel};
}

# This parallel support for the given step
sub disable_parallel {
	my ($this) = @_;
	$this->{parallel} = 1;
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->disable_parallel;
	}
}

# When given a relative path to the build directory, converts it
# to the path that is relative to the source directory. If $path is
# not given, returns a path to the build directory that is relative
# to the source directory.
sub get_build_rel2sourcedir {
	my $this=shift;
	my $path=shift;

	my $dir = '.';
	if ($this->get_builddir()) {
		$dir = $this->_rel2rel($this->get_builddir(), $this->get_sourcedir());
	}
	if (defined $path) {
		return File::Spec->catfile($dir, $path);
	}
	return $dir;
}

# Creates a build directory.
sub mkdir_builddir {
	my $this=shift;
	if ($this->get_builddir()) {
		mkdirs($this->get_builddir());
	}
}

sub check_auto_buildable_clean_oos_buildir {
	my $this = shift;
	my ($step) = @_;
	# This only applies to clean
	return 0 if $step ne 'clean';
	my $builddir = $this->get_builddir;
	# If there is no builddir, then this rule does not apply.
	return 0 if not defined($builddir) or not -d $builddir;
	return 1;
}

sub _generic_doit_in_dir {
	my ($this, $dir, $sub, @args) = @_;
	my %args;
	if (ref($args[0])) {
		%args = %{shift(@args)};
	}
	$args{chdir} = $dir;
	return $sub->(\%args, @args);
}

# Changes working directory to the source directory (if needed),
# calls print_and_doit(@_) and changes working directory back to the
# top directory.
sub doit_in_sourcedir {
	my ($this, @args) = @_;
	$this->_generic_doit_in_dir($this->get_sourcedir, \&print_and_doit, @args);
	return 1;
}

# Changes working directory to the source directory (if needed),
# calls print_and_doit(@_) and changes working directory back to the
# top directory. Errors are ignored.
sub doit_in_sourcedir_noerror {
	my ($this, @args) = @_;
	return $this->_generic_doit_in_dir($this->get_sourcedir, \&print_and_doit_noerror, @args);
}

# Changes working directory to the build directory (if needed),
# calls print_and_doit(@_) and changes working directory back to the
# top directory.
sub doit_in_builddir {
	my ($this, @args) = @_;
	$this->_generic_doit_in_dir($this->get_buildpath, \&print_and_doit, @args);
	return 1;
}

# Changes working directory to the build directory (if needed),
# calls print_and_doit(@_) and changes working directory back to the
# top directory. Errors are ignored.
sub doit_in_builddir_noerror {
	my ($this, @args) = @_;
	return $this->_generic_doit_in_dir($this->get_buildpath, \&print_and_doit_noerror, @args);
}

# In case of out of source tree building, whole build directory
# gets wiped (if it exists) and 1 is returned. If build directory
# had 2 or more levels, empty parent directories are also deleted.
# If build directory does not exist, nothing is done and 0 is returned.
sub rmdir_builddir {
	my $this=shift;
	my $only_empty=shift;
	if ($this->get_builddir()) {
		my $buildpath = $this->get_buildpath();
		if (-d $buildpath) {
			my @dir = File::Spec->splitdir($this->get_build_rel2sourcedir());
			my $peek;
			if (not $only_empty) {
				doit("rm", "-rf", $buildpath);
				pop @dir;
			}
			# If build directory is relative and had 2 or more levels, delete
			# empty parent directories until the source or top directory level.
			if (not File::Spec->file_name_is_absolute($buildpath)) {
				while (($peek=pop @dir) && $peek ne '.' && $peek ne '..') {
					my $dir = $this->get_sourcepath(File::Spec->catdir(@dir, $peek));
					doit("rmdir", "--ignore-fail-on-non-empty", $dir);
					last if -d $dir;
				}
			}
		}
		return 1;
	}
	return 0;
}

# Instance method that is called before performing any step (see below).
# Action name is passed as an argument. Derived classes overriding this
# method should also call SUPER implementation of it.
sub pre_building_step {
	my $this=shift;
	my ($step)=@_;

	# Warn if in source building was enforced but build directory was
	# specified. See enforce_in_source_building().
	if ($this->{warn_insource}) {
		warning("warning: " . $this->NAME() .
		    " does not support building out of source tree. In source building enforced.");
		delete $this->{warn_insource};
	}
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->pre_building_step(@_);
	}
}

# Instance method that is called after performing any step (see below).
# Action name is passed as an argument. Derived classes overriding this
# method should also call SUPER implementation of it.
sub post_building_step {
	my $this=shift;
	my ($step)=@_;
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->post_building_step(@_);
	}
}

# The instance methods below provide support for configuring,
# building, testing, install and cleaning source packages.
# In case of failure, the method may just error() out.
#
# These methods should be overridden by derived classes to
# implement build system specific steps needed to build the
# source. Arbitrary number of custom step arguments might be
# passed. Default implementations do nothing.
#
# Note: For generator build systems, the default is to
# delegate the step to the target build system for all
# steps except configure.
sub configure {
	my $this=shift;
}

sub build {
	my $this=shift;
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->build(@_);
	}
}

sub test {
	my $this=shift;
	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->test(@_);
	}
}

# destdir parameter specifies where to install files.
sub install {
	my $this=shift;
	my ($destdir) = @_;

	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->install(@_);
	}
}

sub clean {
	my $this=shift;

	if ($this->IS_GENERATOR_BUILD_SYSTEM) {
		$this->get_targetbuildsystem->clean(@_);
	}
}


sub _create_buildsystem_instance {
	my ($full_name, $required, %bsopts) = @_;
	my @parts = split(m{[+]}, $full_name, 2);
	my $name = $parts[0];
	my $module = "Debian::Debhelper::Buildsystem::$name";
	if (@parts > 1) {
		if (exists($bsopts{'targetbuildsystem'})) {
			error("Conflicting target buildsystem for ${name} (load as ${full_name}, but target configured in bsopts)");
		}
		$bsopts{'targetbuildsystem'} = $parts[1];
	}

	eval "use $module";
	if ($@) {
		return if not $required;
		error("unable to load build system class '$name': $@");
	}
	return $module->new(%bsopts);
}

1