summaryrefslogtreecommitdiff
path: root/devel/bmake/files/mk/meta2deps.py
blob: 5a5a2315abbdcd5210f16c5e00f2d7b5939bf337 (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
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
#!/usr/bin/env python

from __future__ import print_function

"""
This script parses each "meta" file and extracts the
information needed to deduce build and src dependencies.

It works much the same as the original shell script, but is
*much* more efficient.

The parsing work is handled by the class MetaFile.
We only pay attention to a subset of the information in the
"meta" files.  Specifically:

'CWD'	to initialize our notion.

'C'	to track chdir(2) on a per process basis

'R'	files read are what we really care about.
	directories read, provide a clue to resolving
	subsequent relative paths.  That is if we cannot find
	them relative to 'cwd', we check relative to the last
	dir read.

'W'	files opened for write or read-write,
	for filemon V3 and earlier.
        
'E'	files executed.

'L'	files linked

'V'	the filemon version, this record is used as a clue
	that we have reached the interesting bit.

"""

"""
RCSid:
	$Id: meta2deps.py,v 1.1.1.1 2020/05/24 05:35:53 nia Exp $

	Copyright (c) 2011-2019, Simon J. Gerraty
	Copyright (c) 2011-2017, Juniper Networks, Inc.
	All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions 
	are met: 
	1. Redistributions of source code must retain the above copyright
	   notice, this list of conditions and the following disclaimer. 
	2. Redistributions in binary form must reproduce the above copyright
	   notice, this list of conditions and the following disclaimer in the
	   documentation and/or other materials provided with the distribution.  

	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
 
"""

import os, re, sys

def getv(dict, key, d=None):
    """Lookup key in dict and return value or the supplied default."""
    if key in dict:
        return dict[key]
    return d

def resolve(path, cwd, last_dir=None, debug=0, debug_out=sys.stderr):
    """
    Return an absolute path, resolving via cwd or last_dir if needed.
    """
    if path.endswith('/.'):
        path = path[0:-2]
    if len(path) > 0 and path[0] == '/':
        return path
    if path == '.':
        return cwd
    if path.startswith('./'):
        return cwd + path[1:]
    if last_dir == cwd:
        last_dir = None
    for d in [last_dir, cwd]:
        if not d:
            continue
        if path == '..':
            dw = d.split('/')
            p = '/'.join(dw[:-1])
            if not p:
                p = '/'
            return p
        p = '/'.join([d,path])
        if debug > 2:
            print("looking for:", p, end=' ', file=debug_out)
        if not os.path.exists(p):
            if debug > 2:
                print("nope", file=debug_out)
            p = None
            continue
        if debug > 2:
            print("found:", p, file=debug_out)
        return p
    return None

def cleanpath(path):
    """cleanup path without using realpath(3)"""
    if path.startswith('/'):
        r = '/'
    else:
        r = ''
    p = []
    w = path.split('/')
    for d in w:
        if not d or d == '.':
            continue
        if d == '..':
            try:
                p.pop()
                continue
            except:
                break
        p.append(d)

    return r + '/'.join(p)

def abspath(path, cwd, last_dir=None, debug=0, debug_out=sys.stderr):
    """
    Return an absolute path, resolving via cwd or last_dir if needed.
    this gets called a lot, so we try to avoid calling realpath.
    """
    rpath = resolve(path, cwd, last_dir, debug, debug_out)
    if rpath:
        path = rpath
    if (path.find('/') < 0 or
        path.find('./') > 0 or
        path.endswith('/..')):
        path = cleanpath(path)
    return path

def sort_unique(list, cmp=None, key=None, reverse=False):
    list.sort(cmp, key, reverse)
    nl = []
    le = None
    for e in list:
        if e == le:
            continue
        le = e
        nl.append(e)
    return nl

def add_trims(x):
    return ['/' + x + '/',
            '/' + x, 
            x + '/',
            x]

class MetaFile:
    """class to parse meta files generated by bmake."""

    conf = None
    dirdep_re = None
    host_target = None
    srctops = []
    objroots = []
    excludes = []
    seen = {}
    obj_deps = []
    src_deps = []
    file_deps = []
    
    def __init__(self, name, conf={}):
        """if name is set we will parse it now.
        conf can have the follwing keys:

        SRCTOPS list of tops of the src tree(s).

        CURDIR  the src directory 'bmake' was run from.

        RELDIR  the relative path from SRCTOP to CURDIR

        MACHINE the machine we built for.
                set to 'none' if we are not cross-building.
                More specifically if machine cannot be deduced from objdirs.

        TARGET_SPEC
                Sometimes MACHINE isn't enough.
                
        HOST_TARGET
                when we build for the pseudo machine 'host'
                the object tree uses HOST_TARGET rather than MACHINE.

        OBJROOTS a list of the common prefix for all obj dirs it might
                end in '/' or '-'.

        DPDEPS  names an optional file to which per file dependencies
                will be appended.
                For example if 'some/path/foo.h' is read from SRCTOP
                then 'DPDEPS_some/path/foo.h +=' "RELDIR" is output.
                This can allow 'bmake' to learn all the dirs within
                the tree that depend on 'foo.h'

        EXCLUDES
                A list of paths to ignore.
                ccache(1) can otherwise be trouble.

        debug   desired debug level

        debug_out open file to send debug output to (sys.stderr)

        """
        
        self.name = name
        self.debug = getv(conf, 'debug', 0)
        self.debug_out = getv(conf, 'debug_out', sys.stderr)

        self.machine = getv(conf, 'MACHINE', '')
        self.machine_arch = getv(conf, 'MACHINE_ARCH', '')
        self.target_spec = getv(conf, 'TARGET_SPEC', '')
        self.curdir = getv(conf, 'CURDIR')
        self.reldir = getv(conf, 'RELDIR')
        self.dpdeps = getv(conf, 'DPDEPS')
        self.line = 0

        if not self.conf:
            # some of the steps below we want to do only once
            self.conf = conf
            self.host_target = getv(conf, 'HOST_TARGET')
            for srctop in getv(conf, 'SRCTOPS', []):
                if srctop[-1] != '/':
                    srctop += '/'
                if not srctop in self.srctops:
                    self.srctops.append(srctop)
                _srctop = os.path.realpath(srctop)
                if _srctop[-1] != '/':
                    _srctop += '/'
                if not _srctop in self.srctops:
                    self.srctops.append(_srctop)

            trim_list = add_trims(self.machine)
            if self.machine == 'host':
                trim_list += add_trims(self.host_target)
            if self.target_spec:
                trim_list += add_trims(self.target_spec)

            for objroot in getv(conf, 'OBJROOTS', []):
                for e in trim_list:
                    if objroot.endswith(e):
                        # this is not what we want - fix it
                        objroot = objroot[0:-len(e)]

                if objroot[-1] != '/':
                    objroot += '/'
                if not objroot in self.objroots:
                    self.objroots.append(objroot)
                    _objroot = os.path.realpath(objroot)
                    if objroot[-1] == '/':
                        _objroot += '/'
                    if not _objroot in self.objroots:
                        self.objroots.append(_objroot)

            # we want the longest match
            self.srctops.sort(reverse=True)
            self.objroots.sort(reverse=True)

            self.excludes = getv(conf, 'EXCLUDES', [])

            if self.debug:
                print("host_target=", self.host_target, file=self.debug_out)
                print("srctops=", self.srctops, file=self.debug_out)
                print("objroots=", self.objroots, file=self.debug_out)
                print("excludes=", self.excludes, file=self.debug_out)

            self.dirdep_re = re.compile(r'([^/]+)/(.+)')

        if self.dpdeps and not self.reldir:
            if self.debug:
                print("need reldir:", end=' ', file=self.debug_out)
            if self.curdir:
                srctop = self.find_top(self.curdir, self.srctops)
                if srctop:
                    self.reldir = self.curdir.replace(srctop,'')
                    if self.debug:
                        print(self.reldir, file=self.debug_out)
            if not self.reldir:
                self.dpdeps = None      # we cannot do it?

        self.cwd = os.getcwd()          # make sure this is initialized
        self.last_dir = self.cwd

        if name:
            self.try_parse()

    def reset(self):
        """reset state if we are being passed meta files from multiple directories."""
        self.seen = {}
        self.obj_deps = []
        self.src_deps = []
        self.file_deps = []
          
    def dirdeps(self, sep='\n'):
        """return DIRDEPS"""
        return sep.strip() + sep.join(self.obj_deps)
    
    def src_dirdeps(self, sep='\n'):
        """return SRC_DIRDEPS"""
        return sep.strip() + sep.join(self.src_deps)

    def file_depends(self, out=None):
        """Append DPDEPS_${file} += ${RELDIR}
        for each file we saw, to the output file."""
        if not self.reldir:
            return None
        for f in sort_unique(self.file_deps):
            print('DPDEPS_%s += %s' % (f, self.reldir), file=out)
        # these entries provide for reverse DIRDEPS lookup
        for f in self.obj_deps:
            print('DEPDIRS_%s += %s' % (f, self.reldir), file=out)

    def seenit(self, dir):
        """rememer that we have seen dir."""
        self.seen[dir] = 1
          
    def add(self, list, data, clue=''):
        """add data to list if it isn't already there."""
        if data not in list:
            list.append(data)
            if self.debug:
                print("%s: %sAdd: %s" % (self.name, clue, data), file=self.debug_out)

    def find_top(self, path, list):
        """the logical tree may be split across multiple trees"""
        for top in list:
            if path.startswith(top):
                if self.debug > 2:
                    print("found in", top, file=self.debug_out)
                return top
        return None

    def find_obj(self, objroot, dir, path, input):
        """return path within objroot, taking care of .dirdep files"""
        ddep = None
        for ddepf in [path + '.dirdep', dir + '/.dirdep']:
            if not ddep and os.path.exists(ddepf):
                ddep = open(ddepf, 'r').readline().strip('# \n')
                if self.debug > 1:
                    print("found %s: %s\n" % (ddepf, ddep), file=self.debug_out)
                if ddep.endswith(self.machine):
                    ddep = ddep[0:-(1+len(self.machine))]
                elif self.target_spec and ddep.endswith(self.target_spec):
                    ddep = ddep[0:-(1+len(self.target_spec))]

        if not ddep:
            # no .dirdeps, so remember that we've seen the raw input
            self.seenit(input)
            self.seenit(dir)
            if self.machine == 'none':
                if dir.startswith(objroot):
                    return dir.replace(objroot,'')
                return None
            m = self.dirdep_re.match(dir.replace(objroot,''))
            if m:
                ddep = m.group(2)
                dmachine = m.group(1)
                if dmachine != self.machine:
                    if not (self.machine == 'host' and
                            dmachine == self.host_target):
                        if self.debug > 2:
                            print("adding .%s to %s" % (dmachine, ddep), file=self.debug_out)
                        ddep += '.' + dmachine

        return ddep

    def try_parse(self, name=None, file=None):
        """give file and line number causing exception"""
        try:
            self.parse(name, file)
        except:
            # give a useful clue
            print('{}:{}: '.format(self.name, self.line), end=' ', file=sys.stderr)
            raise
        
    def parse(self, name=None, file=None):
        """A meta file looks like:
        
        # Meta data file "path"
        CMD "command-line"
        CWD "cwd"
        TARGET "target"
        -- command output --
        -- filemon acquired metadata --
        # buildmon version 3
        V 3
        C "pid" "cwd"
        E "pid" "path"
        F "pid" "child"
        R "pid" "path"
        W "pid" "path"
        X "pid" "status"
        D "pid" "path"
        L "pid" "src" "target"
        M "pid" "old" "new"
        S "pid" "path"
        # Bye bye

        We go to some effort to avoid processing a dependency more than once.
        Of the above record types only C,E,F,L,R,V and W are of interest.
        """

        version = 0                     # unknown
        if name:
            self.name = name;
        if file:
            f = file
            cwd = self.last_dir = self.cwd
        else:
            f = open(self.name, 'r')
        skip = True
        pid_cwd = {}
        pid_last_dir = {}
        last_pid = 0

        self.line = 0
        if self.curdir:
            self.seenit(self.curdir)    # we ignore this

        interesting = 'CEFLRV'
        for line in f:
            self.line += 1
            # ignore anything we don't care about
            if not line[0] in interesting:
                continue
            if self.debug > 2:
                print("input:", line, end=' ', file=self.debug_out)
            w = line.split()

            if skip:
                if w[0] == 'V':
                    skip = False
                    version = int(w[1])
                    """
                    if version < 4:
                        # we cannot ignore 'W' records
                        # as they may be 'rw'
                        interesting += 'W'
                    """
                elif w[0] == 'CWD':
                    self.cwd = cwd = self.last_dir = w[1]
                    self.seenit(cwd)    # ignore this
                    if self.debug:
                        print("%s: CWD=%s" % (self.name, cwd), file=self.debug_out)
                continue

            pid = int(w[1])
            if pid != last_pid:
                if last_pid:
                    pid_last_dir[last_pid] = self.last_dir
                cwd = getv(pid_cwd, pid, self.cwd)
                self.last_dir = getv(pid_last_dir, pid, self.cwd)
                last_pid = pid

            # process operations
            if w[0] == 'F':
                npid = int(w[2])
                pid_cwd[npid] = cwd
                pid_last_dir[npid] = cwd
                last_pid = npid
                continue
            elif w[0] == 'C':
                cwd = abspath(w[2], cwd, None, self.debug, self.debug_out)
                if cwd.endswith('/.'):
                    cwd = cwd[0:-2]
                self.last_dir = pid_last_dir[pid] = cwd
                pid_cwd[pid] = cwd
                if self.debug > 1:
                    print("cwd=", cwd, file=self.debug_out)
                continue

            if w[2] in self.seen:
                if self.debug > 2:
                    print("seen:", w[2], file=self.debug_out)
                continue
            # file operations
            if w[0] in 'ML':
                # these are special, tread src as read and
                # target as write
                self.parse_path(w[1].strip("'"), cwd, 'R', w)
                self.parse_path(w[2].strip("'"), cwd, 'W', w)
                continue
            elif w[0] in 'ERWS':
                path = w[2]
                self.parse_path(path, cwd, w[0], w)

        if not file:
            f.close()

    def is_src(self, base, dir, rdir):
        """is base in srctop"""
        for dir in [dir,rdir]:
            if not dir:
                continue
            path = '/'.join([dir,base])
            srctop = self.find_top(path, self.srctops)
            if srctop:
                if self.dpdeps:
                    self.add(self.file_deps, path.replace(srctop,''), 'file')
                self.add(self.src_deps, dir.replace(srctop,''), 'src')
                self.seenit(dir)
                return True
        return False

    def parse_path(self, path, cwd, op=None, w=[]):
        """look at a path for the op specified"""

        if not op:
            op = w[0]

        # we are never interested in .dirdep files as dependencies
        if path.endswith('.dirdep'):
            return
        for p in self.excludes:
            if p and path.startswith(p):
                if self.debug > 2:
                    print("exclude:", p, path, file=self.debug_out)
                return
        # we don't want to resolve the last component if it is
        # a symlink
        path = resolve(path, cwd, self.last_dir, self.debug, self.debug_out)
        if not path:
            return
        dir,base = os.path.split(path)
        if dir in self.seen:
            if self.debug > 2:
                print("seen:", dir, file=self.debug_out)
            return
        # we can have a path in an objdir which is a link
        # to the src dir, we may need to add dependencies for each
        rdir = dir
        dir = abspath(dir, cwd, self.last_dir, self.debug, self.debug_out)
        rdir = os.path.realpath(dir)
        if rdir == dir:
            rdir = None
        # now put path back together
        path = '/'.join([dir,base])
        if self.debug > 1:
            print("raw=%s rdir=%s dir=%s path=%s" % (w[2], rdir, dir, path), file=self.debug_out)
        if op in 'RWS':
            if path in [self.last_dir, cwd, self.cwd, self.curdir]:
                if self.debug > 1:
                    print("skipping:", path, file=self.debug_out)
                return
            if os.path.isdir(path):
                if op in 'RW':
                    self.last_dir = path;
                if self.debug > 1:
                    print("ldir=", self.last_dir, file=self.debug_out)
                return

        if op in 'ERW':
            # finally, we get down to it
            if dir == self.cwd or dir == self.curdir:
                return
            if self.is_src(base, dir, rdir):
                self.seenit(w[2])
                if not rdir:
                    return

            objroot = None
            for dir in [dir,rdir]:
                if not dir:
                    continue
                objroot = self.find_top(dir, self.objroots)
                if objroot:
                    break
            if objroot:
                ddep = self.find_obj(objroot, dir, path, w[2])
                if ddep:
                    self.add(self.obj_deps, ddep, 'obj')
                    if self.dpdeps and objroot.endswith('/stage/'):
                        sp = '/'.join(path.replace(objroot,'').split('/')[1:])
                        self.add(self.file_deps, sp, 'file')
            else:
                # don't waste time looking again
                self.seenit(w[2])
                self.seenit(dir)

                            
def main(argv, klass=MetaFile, xopts='', xoptf=None):
    """Simple driver for class MetaFile.

    Usage:
        script [options] [key=value ...] "meta" ...
        
    Options and key=value pairs contribute to the
    dictionary passed to MetaFile.

    -S "SRCTOP"
                add "SRCTOP" to the "SRCTOPS" list.

    -C "CURDIR"
    
    -O "OBJROOT"
                add "OBJROOT" to the "OBJROOTS" list.

    -m "MACHINE"

    -a "MACHINE_ARCH"

    -H "HOST_TARGET"

    -D "DPDEPS"
    
    -d  bumps debug level

    """
    import getopt

    # import Psyco if we can
    # it can speed things up quite a bit
    have_psyco = 0
    try:
        import psyco
        psyco.full()
        have_psyco = 1
    except:
        pass

    conf = {
        'SRCTOPS': [],
        'OBJROOTS': [],
        'EXCLUDES': [],
        }

    try:
        machine = os.environ['MACHINE']
        if machine:
            conf['MACHINE'] = machine
        machine_arch = os.environ['MACHINE_ARCH']
        if machine_arch:
            conf['MACHINE_ARCH'] = machine_arch
        srctop = os.environ['SB_SRC']
        if srctop:
            conf['SRCTOPS'].append(srctop)
        objroot = os.environ['SB_OBJROOT']
        if objroot:
            conf['OBJROOTS'].append(objroot)
    except:
        pass

    debug = 0
    output = True
    
    opts, args = getopt.getopt(argv[1:], 'a:dS:C:O:R:m:D:H:qT:X:' + xopts)
    for o, a in opts:
        if o == '-a':
            conf['MACHINE_ARCH'] = a
        elif o == '-d':
            debug += 1
        elif o == '-q':
            output = False
        elif o == '-H':
            conf['HOST_TARGET'] = a
        elif o == '-S':
            if a not in conf['SRCTOPS']:
                conf['SRCTOPS'].append(a)
        elif o == '-C':
            conf['CURDIR'] = a
        elif o == '-O':
            if a not in conf['OBJROOTS']:
                conf['OBJROOTS'].append(a)
        elif o == '-R':
            conf['RELDIR'] = a
        elif o == '-D':
            conf['DPDEPS'] = a
        elif o == '-m':
            conf['MACHINE'] = a
        elif o == '-T':
            conf['TARGET_SPEC'] = a
        elif o == '-X':
            if a not in conf['EXCLUDES']:
                conf['EXCLUDES'].append(a)
        elif xoptf:
            xoptf(o, a, conf)

    conf['debug'] = debug

    # get any var=val assignments
    eaten = []
    for a in args:
        if a.find('=') > 0:
            k,v = a.split('=')
            if k in ['SRCTOP','OBJROOT','SRCTOPS','OBJROOTS']:
                if k == 'SRCTOP':
                    k = 'SRCTOPS'
                elif k == 'OBJROOT':
                    k = 'OBJROOTS'
                if v not in conf[k]:
                    conf[k].append(v)
            else:
                conf[k] = v
            eaten.append(a)
            continue
        break

    for a in eaten:
        args.remove(a)

    debug_out = getv(conf, 'debug_out', sys.stderr)

    if debug:
        print("config:", file=debug_out)
        print("psyco=", have_psyco, file=debug_out)
        for k,v in list(conf.items()):
            print("%s=%s" % (k,v), file=debug_out)

    m = None
    for a in args:
        if a.endswith('.meta'):
            if not os.path.exists(a):
                continue
            m = klass(a, conf)
        elif a.startswith('@'):
            # there can actually multiple files per line
            for line in open(a[1:]):
                for f in line.strip().split():
                    if not os.path.exists(f):
                        continue
                    m = klass(f, conf)

    if output and m:
        print(m.dirdeps())

        print(m.src_dirdeps('\nsrc:'))

        dpdeps = getv(conf, 'DPDEPS')
        if dpdeps:
            m.file_depends(open(dpdeps, 'wb'))

    return m

if __name__ == '__main__':
    try:
        main(sys.argv)
    except:
        # yes, this goes to stdout
        print("ERROR: ", sys.exc_info()[1])
        raise