summaryrefslogtreecommitdiff
path: root/apt-pkg/pkgcache.cc
blob: 05f44cad3e0633cd5f1616a2574c2a4cd8a9d46e (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
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
// -*- mode: cpp; mode: fold -*-
// Description								/*{{{*/
// $Id: pkgcache.cc,v 1.37 2003/02/10 01:40:58 doogie Exp $
/* ######################################################################
   
   Package Cache - Accessor code for the cache
   
   Please see doc/apt-pkg/cache.sgml for a more detailed description of 
   this format. Also be sure to keep that file up-to-date!!
   
   This is the general utility functions for cache management. They provide
   a complete set of accessor functions for the cache. The cacheiterators
   header contains the STL-like iterators that can be used to easially
   navigate the cache as well as seemlessly dereference the mmap'd 
   indexes. Use these always.
   
   The main class provides for ways to get package indexes and some
   general lookup functions to start the iterators.

   ##################################################################### */
									/*}}}*/
// Include Files							/*{{{*/
#include<config.h>

#include <apt-pkg/pkgcache.h>
#include <apt-pkg/policy.h>
#include <apt-pkg/version.h>
#include <apt-pkg/error.h>
#include <apt-pkg/strutl.h>
#include <apt-pkg/configuration.h>
#include <apt-pkg/aptconfiguration.h>
#include <apt-pkg/mmap.h>
#include <apt-pkg/macros.h>

#include <stddef.h>
#include <string.h>
#include <ostream>
#include <vector>
#include <string>
#include <sys/stat.h>

#include <apti18n.h>
									/*}}}*/

using std::string;


// Cache::Header::Header - Constructor					/*{{{*/
// ---------------------------------------------------------------------
/* Simply initialize the header */
pkgCache::Header::Header()
{
   Signature = 0x98FE76DC;
   
   /* Whenever the structures change the major version should be bumped,
      whenever the generator changes the minor version should be bumped. */
   MajorVersion = 8;
#if (APT_PKG_MAJOR >= 4 && APT_PKG_MINOR >= 17)
   MinorVersion = 2;
#else
   MinorVersion = 1;
#endif
   Dirty = false;
   
   HeaderSz = sizeof(pkgCache::Header);
   GroupSz = sizeof(pkgCache::Group);
   PackageSz = sizeof(pkgCache::Package);
   PackageFileSz = sizeof(pkgCache::PackageFile);
   VersionSz = sizeof(pkgCache::Version);
   DescriptionSz = sizeof(pkgCache::Description);
   DependencySz = sizeof(pkgCache::Dependency);
   ProvidesSz = sizeof(pkgCache::Provides);
   VerFileSz = sizeof(pkgCache::VerFile);
   DescFileSz = sizeof(pkgCache::DescFile);
   
   GroupCount = 0;
   PackageCount = 0;
   VersionCount = 0;
   DescriptionCount = 0;
   DependsCount = 0;
   PackageFileCount = 0;
   VerFileCount = 0;
   DescFileCount = 0;
   ProvidesCount = 0;
   MaxVerFileSize = 0;
   MaxDescFileSize = 0;
   
   FileList = 0;
   StringList = 0;
   VerSysName = 0;
   Architecture = 0;
   memset(PkgHashTable,0,sizeof(PkgHashTable));
   memset(GrpHashTable,0,sizeof(GrpHashTable));
   memset(Pools,0,sizeof(Pools));

   CacheFileSize = 0;
}
									/*}}}*/
// Cache::Header::CheckSizes - Check if the two headers have same *sz	/*{{{*/
// ---------------------------------------------------------------------
/* */
bool pkgCache::Header::CheckSizes(Header &Against) const
{
   if (HeaderSz == Against.HeaderSz &&
       GroupSz == Against.GroupSz &&
       PackageSz == Against.PackageSz &&
       PackageFileSz == Against.PackageFileSz &&
       VersionSz == Against.VersionSz &&
       DescriptionSz == Against.DescriptionSz &&
       DependencySz == Against.DependencySz &&
       VerFileSz == Against.VerFileSz &&
       DescFileSz == Against.DescFileSz &&
       ProvidesSz == Against.ProvidesSz)
      return true;
   return false;
}
									/*}}}*/

// Cache::pkgCache - Constructor					/*{{{*/
// ---------------------------------------------------------------------
/* */
pkgCache::pkgCache(MMap *Map, bool DoMap) : Map(*Map)
{
   // call getArchitectures() with cached=false to ensure that the 
   // architectures cache is re-evaulated. this is needed in cases
   // when the APT::Architecture field changes between two cache creations
   MultiArchEnabled = APT::Configuration::getArchitectures(false).size() > 1;
   if (DoMap == true)
      ReMap();
}
									/*}}}*/
// Cache::ReMap - Reopen the cache file					/*{{{*/
// ---------------------------------------------------------------------
/* If the file is already closed then this will open it open it. */
bool pkgCache::ReMap(bool const &Errorchecks)
{
   // Apply the typecasts.
   HeaderP = (Header *)Map.Data();
   GrpP = (Group *)Map.Data();
   PkgP = (Package *)Map.Data();
   VerFileP = (VerFile *)Map.Data();
   DescFileP = (DescFile *)Map.Data();
   PkgFileP = (PackageFile *)Map.Data();
   VerP = (Version *)Map.Data();
   DescP = (Description *)Map.Data();
   ProvideP = (Provides *)Map.Data();
   DepP = (Dependency *)Map.Data();
   StringItemP = (StringItem *)Map.Data();
   StrP = (char *)Map.Data();

   if (Errorchecks == false)
      return true;

   if (Map.Size() == 0 || HeaderP == 0)
      return _error->Error(_("Empty package cache"));
   
   // Check the header
   Header DefHeader;
   if (HeaderP->Signature != DefHeader.Signature ||
       HeaderP->Dirty == true)
      return _error->Error(_("The package cache file is corrupted"));
   
   if (HeaderP->MajorVersion != DefHeader.MajorVersion ||
       HeaderP->MinorVersion != DefHeader.MinorVersion ||
       HeaderP->CheckSizes(DefHeader) == false)
      return _error->Error(_("The package cache file is an incompatible version"));

   if (Map.Size() < HeaderP->CacheFileSize)
      return _error->Error(_("The package cache file is corrupted, it is too small"));

   // Locate our VS..
   if (HeaderP->VerSysName == 0 ||
       (VS = pkgVersioningSystem::GetVS(StrP + HeaderP->VerSysName)) == 0)
      return _error->Error(_("This APT does not support the versioning system '%s'"),StrP + HeaderP->VerSysName);

   // Chcek the arhcitecture
   if (HeaderP->Architecture == 0 ||
       _config->Find("APT::Architecture") != StrP + HeaderP->Architecture)
      return _error->Error(_("The package cache was built for a different architecture"));
   return true;
}
									/*}}}*/
// Cache::Hash - Hash a string						/*{{{*/
// ---------------------------------------------------------------------
/* This is used to generate the hash entries for the HashTable. With my
   package list from bo this function gets 94% table usage on a 512 item
   table (480 used items) */
unsigned long pkgCache::sHash(const string &Str) const
{
   unsigned long Hash = 0;
   for (string::const_iterator I = Str.begin(); I != Str.end(); ++I)
      Hash = 41 * Hash + tolower_ascii(*I);
   return Hash % _count(HeaderP->PkgHashTable);
}

unsigned long pkgCache::sHash(const char *Str) const
{
   unsigned long Hash = tolower_ascii(*Str);
   for (const char *I = Str + 1; *I != 0; ++I)
      Hash = 41 * Hash + tolower_ascii(*I);
   return Hash % _count(HeaderP->PkgHashTable);
}
									/*}}}*/
// Cache::SingleArchFindPkg - Locate a package by name			/*{{{*/
// ---------------------------------------------------------------------
/* Returns 0 on error, pointer to the package otherwise
   The multiArch enabled methods will fallback to this one as it is (a bit)
   faster for single arch environments and realworld is mostly singlearch… */
pkgCache::PkgIterator pkgCache::SingleArchFindPkg(const string &Name)
{
   // Look at the hash bucket
   Package *Pkg = PkgP + HeaderP->PkgHashTable[Hash(Name)];
   for (; Pkg != PkgP; Pkg = PkgP + Pkg->NextPackage)
   {
      if (unlikely(Pkg->Name == 0))
	 continue;

      int const cmp = strcasecmp(Name.c_str(), StrP + Pkg->Name);
      if (cmp == 0)
	 return PkgIterator(*this, Pkg);
      else if (cmp < 0)
	 break;
   }
   return PkgIterator(*this,0);
}
									/*}}}*/
// Cache::FindPkg - Locate a package by name				/*{{{*/
// ---------------------------------------------------------------------
/* Returns 0 on error, pointer to the package otherwise */
pkgCache::PkgIterator pkgCache::FindPkg(const string &Name) {
	size_t const found = Name.find(':');
	if (found == string::npos)
	   return FindPkg(Name, "native");
	string const Arch = Name.substr(found+1);
	/* Beware: This is specialcased to handle pkg:any in dependencies as
	   these are linked to virtual pkg:any named packages with all archs.
	   If you want any arch from a given pkg, use FindPkg(pkg,arch) */
	if (Arch == "any")
		return FindPkg(Name, "any");
	return FindPkg(Name.substr(0, found), Arch);
}
									/*}}}*/
// Cache::FindPkg - Locate a package by name				/*{{{*/
// ---------------------------------------------------------------------
/* Returns 0 on error, pointer to the package otherwise */
pkgCache::PkgIterator pkgCache::FindPkg(const string &Name, string const &Arch) {
	/* We make a detour via the GrpIterator here as
	   on a multi-arch environment a group is easier to
	   find than a package (less entries in the buckets) */
	pkgCache::GrpIterator Grp = FindGrp(Name);
	if (Grp.end() == true)
		return PkgIterator(*this,0);

	return Grp.FindPkg(Arch);
}
									/*}}}*/
// Cache::FindGrp - Locate a group by name				/*{{{*/
// ---------------------------------------------------------------------
/* Returns End-Pointer on error, pointer to the group otherwise */
pkgCache::GrpIterator pkgCache::FindGrp(const string &Name) {
	if (unlikely(Name.empty() == true))
		return GrpIterator(*this,0);

	// Look at the hash bucket for the group
	Group *Grp = GrpP + HeaderP->GrpHashTable[sHash(Name)];
	for (; Grp != GrpP; Grp = GrpP + Grp->Next) {
		if (unlikely(Grp->Name == 0))
		   continue;

		int const cmp = strcasecmp(Name.c_str(), StrP + Grp->Name);
		if (cmp == 0)
			return GrpIterator(*this, Grp);
		else if (cmp < 0)
			break;
	}

	return GrpIterator(*this,0);
}
									/*}}}*/
// Cache::CompTypeDeb - Return a string describing the compare type	/*{{{*/
// ---------------------------------------------------------------------
/* This returns a string representation of the dependency compare 
   type in the weird debian style.. */
const char *pkgCache::CompTypeDeb(unsigned char Comp)
{
   const char * const Ops[] = {"","<=",">=","<<",">>","=","!="};
   if (unlikely((unsigned)(Comp & 0xF) >= sizeof(Ops)/sizeof(Ops[0])))
      return "";
   return Ops[Comp & 0xF];
}
									/*}}}*/
// Cache::CompType - Return a string describing the compare type	/*{{{*/
// ---------------------------------------------------------------------
/* This returns a string representation of the dependency compare
   type */
const char *pkgCache::CompType(unsigned char Comp)
{
   const char * const Ops[] = {"","<=",">=","<",">","=","!="};
   if (unlikely((unsigned)(Comp & 0xF) >= sizeof(Ops)/sizeof(Ops[0])))
      return "";
   return Ops[Comp & 0xF];
}
									/*}}}*/
// Cache::DepType - Return a string describing the dep type		/*{{{*/
// ---------------------------------------------------------------------
/* */
const char *pkgCache::DepType(unsigned char Type)
{
   const char *Types[] = {"",_("Depends"),_("PreDepends"),_("Suggests"),
                          _("Recommends"),_("Conflicts"),_("Replaces"),
                          _("Obsoletes"),_("Breaks"), _("Enhances")};
   if (Type < sizeof(Types)/sizeof(*Types))
      return Types[Type];
   return "";
}
									/*}}}*/
// Cache::Priority - Convert a priority value to a string		/*{{{*/
// ---------------------------------------------------------------------
/* */
const char *pkgCache::Priority(unsigned char Prio)
{
   const char *Mapping[] = {0,_("important"),_("required"),_("standard"),
                            _("optional"),_("extra")};
   if (Prio < _count(Mapping))
      return Mapping[Prio];
   return 0;
}
									/*}}}*/
// GrpIterator::FindPkg - Locate a package by arch			/*{{{*/
// ---------------------------------------------------------------------
/* Returns an End-Pointer on error, pointer to the package otherwise */
pkgCache::PkgIterator pkgCache::GrpIterator::FindPkg(string Arch) const {
	if (unlikely(IsGood() == false || S->FirstPackage == 0))
		return PkgIterator(*Owner, 0);

	/* If we accept any package we simply return the "first"
	   package in this group (the last one added). */
	if (Arch == "any")
		return PkgIterator(*Owner, Owner->PkgP + S->FirstPackage);

	char const* const myArch = Owner->NativeArch();
	/* Most of the time the package for our native architecture is
	   the one we add at first to the cache, but this would be the
	   last one we check, so we do it now. */
	if (Arch == "native" || Arch == myArch || Arch == "all") {
		pkgCache::Package *Pkg = Owner->PkgP + S->LastPackage;
		if (strcasecmp(myArch, Owner->StrP + Pkg->Arch) == 0)
			return PkgIterator(*Owner, Pkg);
		Arch = myArch;
	}

	/* Iterate over the list to find the matching arch
	   unfortunately this list includes "package noise"
	   (= different packages with same calculated hash),
	   so we need to check the name also */
	for (pkgCache::Package *Pkg = PackageList(); Pkg != Owner->PkgP;
	     Pkg = Owner->PkgP + Pkg->NextPackage) {
		if (S->Name == Pkg->Name &&
		    stringcasecmp(Arch, Owner->StrP + Pkg->Arch) == 0)
			return PkgIterator(*Owner, Pkg);
		if ((Owner->PkgP + S->LastPackage) == Pkg)
			break;
	}

	return PkgIterator(*Owner, 0);
}
									/*}}}*/
// GrpIterator::FindPreferredPkg - Locate the "best" package		/*{{{*/
// ---------------------------------------------------------------------
/* Returns an End-Pointer on error, pointer to the package otherwise */
pkgCache::PkgIterator pkgCache::GrpIterator::FindPreferredPkg(bool const &PreferNonVirtual) const {
	pkgCache::PkgIterator Pkg = FindPkg("native");
	if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
		return Pkg;

	std::vector<std::string> const archs = APT::Configuration::getArchitectures();
	for (std::vector<std::string>::const_iterator a = archs.begin();
	     a != archs.end(); ++a) {
		Pkg = FindPkg(*a);
		if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
			return Pkg;
	}
	// packages without an architecture
	Pkg = FindPkg("none");
	if (Pkg.end() == false && (PreferNonVirtual == false || Pkg->VersionList != 0))
		return Pkg;

	if (PreferNonVirtual == true)
		return FindPreferredPkg(false);
	return PkgIterator(*Owner, 0);
}
									/*}}}*/
// GrpIterator::NextPkg - Locate the next package in the group		/*{{{*/
// ---------------------------------------------------------------------
/* Returns an End-Pointer on error, pointer to the package otherwise.
   We can't simply ++ to the next as the next package of the last will
   be from a different group (with the same hash value) */
pkgCache::PkgIterator pkgCache::GrpIterator::NextPkg(pkgCache::PkgIterator const &LastPkg) const {
	if (unlikely(IsGood() == false || S->FirstPackage == 0 ||
	    LastPkg.end() == true))
		return PkgIterator(*Owner, 0);

	if (S->LastPackage == LastPkg.Index())
		return PkgIterator(*Owner, 0);

	return PkgIterator(*Owner, Owner->PkgP + LastPkg->NextPackage);
}
									/*}}}*/
// GrpIterator::operator ++ - Postfix incr				/*{{{*/
// ---------------------------------------------------------------------
/* This will advance to the next logical group in the hash table. */
void pkgCache::GrpIterator::operator ++(int)
{
   // Follow the current links
   if (S != Owner->GrpP)
      S = Owner->GrpP + S->Next;

   // Follow the hash table
   while (S == Owner->GrpP && (HashIndex+1) < (signed)_count(Owner->HeaderP->GrpHashTable))
   {
      HashIndex++;
      S = Owner->GrpP + Owner->HeaderP->GrpHashTable[HashIndex];
   }
}
									/*}}}*/
// PkgIterator::operator ++ - Postfix incr				/*{{{*/
// ---------------------------------------------------------------------
/* This will advance to the next logical package in the hash table. */
void pkgCache::PkgIterator::operator ++(int)
{
   // Follow the current links
   if (S != Owner->PkgP)
      S = Owner->PkgP + S->NextPackage;

   // Follow the hash table
   while (S == Owner->PkgP && (HashIndex+1) < (signed)_count(Owner->HeaderP->PkgHashTable))
   {
      HashIndex++;
      S = Owner->PkgP + Owner->HeaderP->PkgHashTable[HashIndex];
   }
}
									/*}}}*/
// PkgIterator::State - Check the State of the package			/*{{{*/
// ---------------------------------------------------------------------
/* By this we mean if it is either cleanly installed or cleanly removed. */
pkgCache::PkgIterator::OkState pkgCache::PkgIterator::State() const
{  
   if (S->InstState == pkgCache::State::ReInstReq ||
       S->InstState == pkgCache::State::HoldReInstReq)
      return NeedsUnpack;
   
   if (S->CurrentState == pkgCache::State::UnPacked ||
       S->CurrentState == pkgCache::State::HalfConfigured)
      // we leave triggers alone complettely. dpkg deals with
      // them in a hard-to-predict manner and if they get 
      // resolved by dpkg before apt run dpkg --configure on 
      // the TriggersPending package dpkg returns a error
      //Pkg->CurrentState == pkgCache::State::TriggersAwaited
      //Pkg->CurrentState == pkgCache::State::TriggersPending)
      return NeedsConfigure;
   
   if (S->CurrentState == pkgCache::State::HalfInstalled ||
       S->InstState != pkgCache::State::Ok)
      return NeedsUnpack;
      
   return NeedsNothing;
}
									/*}}}*/
// PkgIterator::CandVersion - Returns the candidate version string	/*{{{*/
// ---------------------------------------------------------------------
/* Return string representing of the candidate version. */
const char *
pkgCache::PkgIterator::CandVersion() const
{
  //TargetVer is empty, so don't use it.
  VerIterator version = pkgPolicy(Owner).GetCandidateVer(*this);
  if (version.IsGood())
    return version.VerStr();
  return 0;
}
									/*}}}*/
// PkgIterator::CurVersion - Returns the current version string		/*{{{*/
// ---------------------------------------------------------------------
/* Return string representing of the current version. */
const char *
pkgCache::PkgIterator::CurVersion() const
{
  VerIterator version = CurrentVer();
  if (version.IsGood())
    return CurrentVer().VerStr();
  return 0;
}
									/*}}}*/
// ostream operator to handle string representation of a package	/*{{{*/
// ---------------------------------------------------------------------
/* Output name < cur.rent.version -> candid.ate.version | new.est.version > (section)
   Note that the characters <|>() are all literal above. Versions will be omitted
   if they provide no new information (e.g. there is no newer version than candidate)
   If no version and/or section can be found "none" is used. */
std::ostream& 
operator<<(std::ostream& out, pkgCache::PkgIterator Pkg) 
{
   if (Pkg.end() == true)
      return out << "invalid package";

   string current = string(Pkg.CurVersion() == 0 ? "none" : Pkg.CurVersion());
   string candidate = string(Pkg.CandVersion() == 0 ? "none" : Pkg.CandVersion());
   string newest = string(Pkg.VersionList().end() ? "none" : Pkg.VersionList().VerStr());

   out << Pkg.Name() << " [ " << Pkg.Arch() << " ] < " << current;
   if (current != candidate)
      out << " -> " << candidate;
   if ( newest != "none" && candidate != newest)
      out << " | " << newest;
   if (Pkg->VersionList == 0)
      out << " > ( none )";
   else
      out << " > ( " << string(Pkg.VersionList().Section()==0?"unknown":Pkg.VersionList().Section()) << " )";
   return out;
}
									/*}}}*/
// PkgIterator::FullName - Returns Name and (maybe) Architecture	/*{{{*/
// ---------------------------------------------------------------------
/* Returns a name:arch string */
std::string pkgCache::PkgIterator::FullName(bool const &Pretty) const
{
   string fullname = Name();
   if (Pretty == false ||
       (strcmp(Arch(), "all") != 0 &&
	strcmp(Owner->NativeArch(), Arch()) != 0))
      return fullname.append(":").append(Arch());
   return fullname;
}
									/*}}}*/
// DepIterator::IsCritical - Returns true if the dep is important	/*{{{*/
// ---------------------------------------------------------------------
/* Currently critical deps are defined as depends, predepends and
   conflicts (including dpkg's Breaks fields). */
bool pkgCache::DepIterator::IsCritical() const
{
   if (IsNegative() == true ||
       S->Type == pkgCache::Dep::Depends ||
       S->Type == pkgCache::Dep::PreDepends)
      return true;
   return false;
}
									/*}}}*/
// DepIterator::IsNegative - Returns true if the dep is a negative one	/*{{{*/
// ---------------------------------------------------------------------
/* Some dependencies are positive like Depends and Recommends, others
   are negative like Conflicts which can and should be handled differently */
bool pkgCache::DepIterator::IsNegative() const
{
   return S->Type == Dep::DpkgBreaks ||
	  S->Type == Dep::Conflicts ||
	  S->Type == Dep::Obsoletes;
}
									/*}}}*/
// DepIterator::SmartTargetPkg - Resolve dep target pointers w/provides	/*{{{*/
// ---------------------------------------------------------------------
/* This intellegently looks at dep target packages and tries to figure
   out which package should be used. This is needed to nicely handle
   provide mapping. If the target package has no other providing packages
   then it returned. Otherwise the providing list is looked at to 
   see if there is one one unique providing package if so it is returned.
   Otherwise true is returned and the target package is set. The return
   result indicates whether the node should be expandable 
 
   In Conjunction with the DepCache the value of Result may not be 
   super-good since the policy may have made it uninstallable. Using
   AllTargets is better in this case. */
bool pkgCache::DepIterator::SmartTargetPkg(PkgIterator &Result) const
{
   Result = TargetPkg();
   
   // No provides at all
   if (Result->ProvidesList == 0)
      return false;
   
   // There is the Base package and the providing ones which is at least 2
   if (Result->VersionList != 0)
      return true;
      
   /* We have to skip over indirect provisions of the package that
      owns the dependency. For instance, if libc5-dev depends on the
      virtual package libc-dev which is provided by libc5-dev and libc6-dev
      we must ignore libc5-dev when considering the provides list. */ 
   PrvIterator PStart = Result.ProvidesList();
   for (; PStart.end() != true && PStart.OwnerPkg() == ParentPkg(); ++PStart);

   // Nothing but indirect self provides
   if (PStart.end() == true)
      return false;
   
   // Check for single packages in the provides list
   PrvIterator P = PStart;
   for (; P.end() != true; ++P)
   {
      // Skip over self provides
      if (P.OwnerPkg() == ParentPkg())
	 continue;
      if (PStart.OwnerPkg() != P.OwnerPkg())
	 break;
   }

   Result = PStart.OwnerPkg();
   
   // Check for non dups
   if (P.end() != true)
      return true;
   
   return false;
}
									/*}}}*/
// DepIterator::AllTargets - Returns the set of all possible targets	/*{{{*/
// ---------------------------------------------------------------------
/* This is a more useful version of TargetPkg() that follows versioned
   provides. It includes every possible package-version that could satisfy
   the dependency. The last item in the list has a 0. The resulting pointer
   must be delete [] 'd */
pkgCache::Version **pkgCache::DepIterator::AllTargets() const
{
   Version **Res = 0;
   unsigned long Size =0;
   while (1)
   {
      Version **End = Res;
      PkgIterator DPkg = TargetPkg();

      // Walk along the actual package providing versions
      for (VerIterator I = DPkg.VersionList(); I.end() == false; ++I)
      {
	 if (IsIgnorable(I.ParentPkg()) == true)
	    continue;
	 if (IsSatisfied(I) == false)
	    continue;

	 Size++;
	 if (Res != 0)
	    *End++ = I;
      }
      
      // Follow all provides
      for (PrvIterator I = DPkg.ProvidesList(); I.end() == false; ++I)
      {
	 if (IsIgnorable(I) == true)
	    continue;
	 if (IsSatisfied(I) == false)
	    continue;

	 Size++;
	 if (Res != 0)
	    *End++ = I.OwnerVer();
      }
      
      // Do it again and write it into the array
      if (Res == 0)
      {
	 Res = new Version *[Size+1];
	 Size = 0;
      }
      else
      {
	 *End = 0;
	 break;
      }      
   }
   
   return Res;
}
									/*}}}*/
// DepIterator::GlobOr - Compute an OR group				/*{{{*/
// ---------------------------------------------------------------------
/* This Takes an iterator, iterates past the current dependency grouping
   and returns Start and End so that so End is the final element
   in the group, if End == Start then D is End++ and End is the
   dependency D was pointing to. Use in loops to iterate sensibly. */
void pkgCache::DepIterator::GlobOr(DepIterator &Start,DepIterator &End)
{
   // Compute a single dependency element (glob or)
   Start = *this;
   End = *this;
   for (bool LastOR = true; end() == false && LastOR == true;)
   {
      LastOR = (S->CompareOp & pkgCache::Dep::Or) == pkgCache::Dep::Or;
      (*this)++;
      if (LastOR == true)
	 End = (*this);
   }
}
									/*}}}*/
// DepIterator::IsIgnorable - should this packag/providr be ignored?	/*{{{*/
// ---------------------------------------------------------------------
/* Deps like self-conflicts should be ignored as well as implicit conflicts
   on virtual packages. */
bool pkgCache::DepIterator::IsIgnorable(PkgIterator const &/*Pkg*/) const
{
   if (IsNegative() == false)
      return false;

   pkgCache::PkgIterator PP = ParentPkg();
   pkgCache::PkgIterator PT = TargetPkg();
   if (PP->Group != PT->Group)
      return false;
   // self-conflict
   if (PP == PT)
      return true;
   pkgCache::VerIterator PV = ParentVer();
   // ignore group-conflict on a M-A:same package - but not our implicit dependencies
   // so that we can have M-A:same packages conflicting with their own real name
   if ((PV->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
   {
      // Replaces: ${self}:other ( << ${binary:Version})
      if (S->Type == pkgCache::Dep::Replaces && S->CompareOp == pkgCache::Dep::Less && strcmp(PV.VerStr(), TargetVer()) == 0)
	 return false;
      // Breaks: ${self}:other (!= ${binary:Version})
      if (S->Type == pkgCache::Dep::DpkgBreaks && S->CompareOp == pkgCache::Dep::NotEquals && strcmp(PV.VerStr(), TargetVer()) == 0)
	 return false;
      return true;
   }

   return false;
}
bool pkgCache::DepIterator::IsIgnorable(PrvIterator const &Prv) const
{
   if (IsNegative() == false)
      return false;

   PkgIterator const Pkg = ParentPkg();
   /* Provides may never be applied against the same package (or group)
      if it is a conflicts. See the comment above. */
   if (Prv.OwnerPkg()->Group == Pkg->Group)
      return true;
   // Implicit group-conflicts should not be applied on providers of other groups
   if (Pkg->Group == TargetPkg()->Group && Prv.OwnerPkg()->Group != Pkg->Group)
      return true;

   return false;
}
									/*}}}*/
// DepIterator::IsMultiArchImplicit - added by the cache generation	/*{{{*/
// ---------------------------------------------------------------------
/* MultiArch can be translated to SingleArch for an resolver and we did so,
   by adding dependencies to help the resolver understand the problem, but
   sometimes it is needed to identify these to ignore them… */
bool pkgCache::DepIterator::IsMultiArchImplicit() const
{
   if (ParentPkg()->Arch != TargetPkg()->Arch &&
       (S->Type == pkgCache::Dep::Replaces ||
	S->Type == pkgCache::Dep::DpkgBreaks ||
	S->Type == pkgCache::Dep::Conflicts))
      return true;
   return false;
}
									/*}}}*/
// DepIterator::IsSatisfied - check if a version satisfied the dependency /*{{{*/
bool pkgCache::DepIterator::IsSatisfied(VerIterator const &Ver) const
{
   return Owner->VS->CheckDep(Ver.VerStr(),S->CompareOp,TargetVer());
}
bool pkgCache::DepIterator::IsSatisfied(PrvIterator const &Prv) const
{
   return Owner->VS->CheckDep(Prv.ProvideVersion(),S->CompareOp,TargetVer());
}
									/*}}}*/
// ostream operator to handle string representation of a dependecy	/*{{{*/
// ---------------------------------------------------------------------
/* */
std::ostream& operator<<(std::ostream& out, pkgCache::DepIterator D)
{
   if (D.end() == true)
      return out << "invalid dependency";

   pkgCache::PkgIterator P = D.ParentPkg();
   pkgCache::PkgIterator T = D.TargetPkg();

   out << (P.end() ? "invalid pkg" : P.FullName(false)) << " " << D.DepType()
	<< " on ";
   if (T.end() == true)
      out << "invalid pkg";
   else
      out << T;

   if (D->Version != 0)
      out << " (" << D.CompType() << " " << D.TargetVer() << ")";

   return out;
}
									/*}}}*/
// VerIterator::CompareVer - Fast version compare for same pkgs		/*{{{*/
// ---------------------------------------------------------------------
/* This just looks over the version list to see if B is listed before A. In
   most cases this will return in under 4 checks, ver lists are short. */
int pkgCache::VerIterator::CompareVer(const VerIterator &B) const
{
   // Check if they are equal
   if (*this == B)
      return 0;
   if (end() == true)
      return -1;
   if (B.end() == true)
      return 1;
       
   /* Start at A and look for B. If B is found then A > B otherwise
      B was before A so A < B */
   VerIterator I = *this;
   for (;I.end() == false; ++I)
      if (I == B)
	 return 1;
   return -1;
}
									/*}}}*/
// VerIterator::Downloadable - Checks if the version is downloadable	/*{{{*/
// ---------------------------------------------------------------------
/* */
APT_PURE bool pkgCache::VerIterator::Downloadable() const
{
   VerFileIterator Files = FileList();
   for (; Files.end() == false; ++Files)
      if ((Files.File()->Flags & pkgCache::Flag::NotSource) != pkgCache::Flag::NotSource)
	 return true;
   return false;
}
									/*}}}*/
// VerIterator::Automatic - Check if this version is 'automatic'	/*{{{*/
// ---------------------------------------------------------------------
/* This checks to see if any of the versions files are not NotAutomatic. 
   True if this version is selectable for automatic installation. */
APT_PURE bool pkgCache::VerIterator::Automatic() const
{
   VerFileIterator Files = FileList();
   for (; Files.end() == false; ++Files)
      // Do not check ButAutomaticUpgrades here as it is kind of automatic…
      if ((Files.File()->Flags & pkgCache::Flag::NotAutomatic) != pkgCache::Flag::NotAutomatic)
	 return true;
   return false;
}
									/*}}}*/
// VerIterator::NewestFile - Return the newest file version relation	/*{{{*/
// ---------------------------------------------------------------------
/* This looks at the version numbers associated with all of the sources
   this version is in and returns the highest.*/
pkgCache::VerFileIterator pkgCache::VerIterator::NewestFile() const
{
   VerFileIterator Files = FileList();
   VerFileIterator Highest = Files;
   for (; Files.end() == false; ++Files)
   {
      if (Owner->VS->CmpReleaseVer(Files.File().Version(),Highest.File().Version()) > 0)
	 Highest = Files;
   }
   
   return Highest;
}
									/*}}}*/
// VerIterator::RelStr - Release description string			/*{{{*/
// ---------------------------------------------------------------------
/* This describes the version from a release-centric manner. The output is a 
   list of Label:Version/Archive */
string pkgCache::VerIterator::RelStr() const
{
   bool First = true;
   string Res;
   for (pkgCache::VerFileIterator I = this->FileList(); I.end() == false; ++I)
   {
      // Do not print 'not source' entries'
      pkgCache::PkgFileIterator File = I.File();
      if ((File->Flags & pkgCache::Flag::NotSource) == pkgCache::Flag::NotSource)
	 continue;

      // See if we have already printed this out..
      bool Seen = false;
      for (pkgCache::VerFileIterator J = this->FileList(); I != J; ++J)
      {
	 pkgCache::PkgFileIterator File2 = J.File();
	 if (File2->Label == 0 || File->Label == 0)
	    continue;

	 if (strcmp(File.Label(),File2.Label()) != 0)
	    continue;
	 
	 if (File2->Version == File->Version)
	 {
	    Seen = true;
	    break;
	 }
	 if (File2->Version == 0 || File->Version == 0)
	    break;
	 if (strcmp(File.Version(),File2.Version()) == 0)
	    Seen = true;
      }
      
      if (Seen == true)
	 continue;
      
      if (First == false)
	 Res += ", ";
      else
	 First = false;
      
      if (File->Label != 0)
	 Res = Res + File.Label() + ':';

      if (File->Archive != 0)
      {
	 if (File->Version == 0)
	    Res += File.Archive();
	 else
	    Res = Res + File.Version() + '/' +  File.Archive();
      }
      else
      {
	 // No release file, print the host name that this came from
	 if (File->Site == 0 || File.Site()[0] == 0)
	    Res += "localhost";
	 else
	    Res += File.Site();
      }      
   }
   if (S->ParentPkg != 0)
      Res.append(" [").append(Arch()).append("]");
   return Res;
}
									/*}}}*/
// VerIterator::MultiArchType - string representing MultiArch flag	/*{{{*/
const char * pkgCache::VerIterator::MultiArchType() const
{
   if ((S->MultiArch & pkgCache::Version::Same) == pkgCache::Version::Same)
      return "same";
   else if ((S->MultiArch & pkgCache::Version::Foreign) == pkgCache::Version::Foreign)
      return "foreign";
   else if ((S->MultiArch & pkgCache::Version::Allowed) == pkgCache::Version::Allowed)
      return "allowed";
   return "none";
}
									/*}}}*/
// PkgFileIterator::IsOk - Checks if the cache is in sync with the file	/*{{{*/
// ---------------------------------------------------------------------
/* This stats the file and compares its stats with the ones that were
   stored during generation. Date checks should probably also be 
   included here. */
bool pkgCache::PkgFileIterator::IsOk()
{
   struct stat Buf;
   if (stat(FileName(),&Buf) != 0)
      return false;

   if (Buf.st_size != (signed)S->Size || Buf.st_mtime != S->mtime)
      return false;

   return true;
}
									/*}}}*/
// PkgFileIterator::RelStr - Return the release string			/*{{{*/
// ---------------------------------------------------------------------
/* */
string pkgCache::PkgFileIterator::RelStr()
{
   string Res;
   if (Version() != 0)
      Res = Res + (Res.empty() == true?"v=":",v=") + Version();
   if (Origin() != 0)
      Res = Res + (Res.empty() == true?"o=":",o=")  + Origin();
   if (Archive() != 0)
      Res = Res + (Res.empty() == true?"a=":",a=")  + Archive();
   if (Codename() != 0)
      Res = Res + (Res.empty() == true?"n=":",n=")  + Codename();
   if (Label() != 0)
      Res = Res + (Res.empty() == true?"l=":",l=")  + Label();
   if (Component() != 0)
      Res = Res + (Res.empty() == true?"c=":",c=")  + Component();
   if (Architecture() != 0)
      Res = Res + (Res.empty() == true?"b=":",b=")  + Architecture();
   return Res;
}
									/*}}}*/
// VerIterator::TranslatedDescription - Return the a DescIter for locale/*{{{*/
// ---------------------------------------------------------------------
/* return a DescIter for the current locale or the default if none is
 * found
 */
pkgCache::DescIterator pkgCache::VerIterator::TranslatedDescription() const
{
   std::vector<string> const lang = APT::Configuration::getLanguages();
   for (std::vector<string>::const_iterator l = lang.begin();
	l != lang.end(); ++l)
   {
      pkgCache::DescIterator Desc = DescriptionList();
      for (; Desc.end() == false; ++Desc)
	 if (*l == Desc.LanguageCode())
	    break;
      if (Desc.end() == true)
      {
	 if (*l == "en")
	 {
	    Desc = DescriptionList();
	    for (; Desc.end() == false; ++Desc)
	       if (strcmp(Desc.LanguageCode(), "") == 0)
		  break;
	    if (Desc.end() == true)
	       continue;
	 }
	 else
	    continue;
      }
      return Desc;
   }
   for (pkgCache::DescIterator Desc = DescriptionList();
	Desc.end() == false; ++Desc)
      if (strcmp(Desc.LanguageCode(), "") == 0)
	 return Desc;
   return DescriptionList();
}

									/*}}}*/
// PrvIterator::IsMultiArchImplicit - added by the cache generation	/*{{{*/
// ---------------------------------------------------------------------
/* MultiArch can be translated to SingleArch for an resolver and we did so,
   by adding provides to help the resolver understand the problem, but
   sometimes it is needed to identify these to ignore them… */
bool pkgCache::PrvIterator::IsMultiArchImplicit() const
{
   pkgCache::PkgIterator const Owner = OwnerPkg();
   pkgCache::PkgIterator const Parent = ParentPkg();
   if (strcmp(Owner.Arch(), Parent.Arch()) != 0 || Owner->Name == Parent->Name)
      return true;
   return false;
}
									/*}}}*/