apt-pkg/acquire-item.h

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: acquire-item.h,v 1.26.2.3 2004/01/02 18:51:00 mdz Exp $
   4 /* ######################################################################
   5
   6    Acquire Item - Item to acquire
   7
   8    When an item is instantiated it will add it self to the local list in
   9    the Owner Acquire class. Derived classes will then call QueueURI to
  10    register all the URI's they wish to fetch at the initial moment.
  11
  12    Three item classes are provided to provide functionality for
  13    downloading of Index, Translation and Packages files.
  14
  15    A Archive class is provided for downloading .deb files. It does Md5
  16    checking and source location as well as a retry algorithm.
  17
  18    ##################################################################### */
  19                                                                         /*}}}*/
  20 #ifndef PKGLIB_ACQUIRE_ITEM_H
  21 #define PKGLIB_ACQUIRE_ITEM_H
  22
  23 #include <apt-pkg/acquire.h>
  24 #include <apt-pkg/indexfile.h>
  25 #include <apt-pkg/vendor.h>
  26 #include <apt-pkg/sourcelist.h>
  27 #include <apt-pkg/pkgrecords.h>
  28 #include <apt-pkg/indexrecords.h>
  29
  30
  31 /** \addtogroup acquire
  32  *  @{
  33  *
  34  *  \file acquire-item.h
  35  */
  36
  37 /** \brief Represents the process by which a pkgAcquire object should
  38  *  retrieve a file or a collection of files.
  39  *
  40  *  By convention, Item subclasses should insert themselves into the
  41  *  acquire queue when they are created by calling QueueURI(), and
  42  *  remove themselves by calling Dequeue() when either Done() or
  43  *  Failed() is invoked.  Item objects are also responsible for
  44  *  notifying the download progress indicator (accessible via
  45  *  #Owner->Log) of their status.
  46  *
  47  *  \see pkgAcquire
  48  */
  49 class pkgAcquire::Item
  50 {
  51    protected:
  52
  53    /** \brief The acquire object with which this item is associated. */
  54    pkgAcquire *Owner;
  55
  56    /** \brief Insert this item into its owner's queue.
  57     *
  58     *  \param ItemDesc Metadata about this item (its URI and
  59     *  description).
  60     */
  61    inline void QueueURI(ItemDesc &Item)
  62                  {Owner->Enqueue(Item);};
  63
  64    /** \brief Remove this item from its owner's queue. */
  65    inline void Dequeue() {Owner->Dequeue(this);};
  66
  67    /** \brief Rename a file without modifying its timestamp.
  68     *
  69     *  Many item methods call this as their final action.
  70     *
  71     *  \param From The file to be renamed.
  72     *
  73     *  \param To The new name of #From.  If #To exists it will be
  74     *  overwritten.
  75     */
  76    void Rename(string From,string To);
  77
  78    public:
  79
  80    /** \brief The current status of this item. */
  81    enum ItemState
  82      {
  83        /** \brief The item is waiting to be downloaded. */
  84        StatIdle,
  85
  86        /** \brief The item is currently being downloaded. */
  87        StatFetching,
  88
  89        /** \brief The item has been successfully downloaded. */
  90        StatDone,
  91
  92        /** \brief An error was encountered while downloading this
  93         *  item.
  94         */
  95        StatError,
  96
  97        /** \brief The item was downloaded but its authenticity could
  98         *  not be verified.
  99         */
 100        StatAuthError
 101      } Status;
 102
 103    /** \brief Contains a textual description of the error encountered
 104     *  if #Status is #StatError or #StatAuthError.
 105     */
 106    string ErrorText;
 107
 108    /** \brief The size of the object to fetch. */
 109    unsigned long FileSize;
 110
 111    /** \brief How much of the object was already fetched. */
 112    unsigned long PartialSize;
 113
 114    /** \brief If not \b NULL, contains the name of a subprocess that
 115     *  is operating on this object (for instance, "gzip" or "gpgv").
 116     */
 117    const char *Mode;
 118
 119    /** \brief A client-supplied unique identifier.
 120     *
 121     *  This field is initalized to 0; it is meant to be filled in by
 122     *  clients that wish to use it to uniquely identify items.
 123     *
 124     *  \todo it's unused in apt itself
 125     */
 126    unsigned long ID;
 127
 128    /** \brief If \b true, the entire object has been successfully fetched.
 129     *
 130     *  Subclasses should set this to \b true when appropriate.
 131     */
 132    bool Complete;
 133
 134    /** \brief If \b true, the URI of this object is "local".
 135     *
 136     *  The only effect of this field is to exclude the object from the
 137     *  download progress indicator's overall statistics.
 138     */
 139    bool Local;
 140
 141    /** \brief The number of fetch queues into which this item has been
 142     *  inserted.
 143     *
 144     *  There is one queue for each source from which an item could be
 145     *  downloaded.
 146     *
 147     *  \sa pkgAcquire
 148     */
 149    unsigned int QueueCounter;
 150
 151    /** \brief The name of the file into which the retrieved object
 152     *  will be written.
 153     */
 154    string DestFile;
 155
 156    /** \brief Invoked by the acquire worker when the object couldn't
 157     *  be fetched.
 158     *
 159     *  This is a branch of the continuation of the fetch process.
 160     *
 161     *  \param Message An RFC822-formatted message from the acquire
 162     *  method describing what went wrong.  Use LookupTag() to parse
 163     *  it.
 164     *
 165     *  \param Cnf The method via which the worker tried to fetch this object.
 166     *
 167     *  \sa pkgAcqMethod
 168     */
 169    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 170
 171    /** \brief Invoked by the acquire worker when the object was
 172     *  fetched successfully.
 173     *
 174     *  Note that the object might \e not have been written to
 175     *  DestFile; check for the presence of an Alt-Filename entry in
 176     *  Message to find the file to which it was really written.
 177     *
 178     *  Done is often used to switch from one stage of the processing
 179     *  to the next (e.g. fetching, unpacking, copying).  It is one
 180     *  branch of the continuation of the fetch process.
 181     *
 182     *  \param Message Data from the acquire method.  Use LookupTag()
 183     *  to parse it.
 184     *  \param Size The size of the object that was fetched.
 185     *  \param Md5Hash The MD5Sum of the object that was fetched.
 186     *  \param Cnf The method via which the object was fetched.
 187     *
 188     *  \sa pkgAcqMethod
 189     */
 190    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 191                      pkgAcquire::MethodConfig *Cnf);
 192
 193    /** \brief Invoked when the worker starts to fetch this object.
 194     *
 195     *  \param Message RFC822-formatted data from the worker process.
 196     *  Use LookupTag() to parse it.
 197     *
 198     *  \param Size The size of the object being fetched.
 199     *
 200     *  \sa pkgAcqMethod
 201     */
 202    virtual void Start(string Message,unsigned long Size);
 203
 204    /** \brief Custom headers to be sent to the fetch process.
 205     *
 206     *  \return a string containing RFC822-style headers that are to be
 207     *  inserted into the 600 URI Acquire message sent to the fetch
 208     *  subprocess.  The headers are inserted after a newline-less
 209     *  line, so they should (if nonempty) have a leading newline and
 210     *  no trailing newline.
 211     */
 212    virtual string Custom600Headers() {return string();};
 213
 214    /** \brief A "descriptive" URI-like string.
 215     *
 216     *  \return a URI that should be used to describe what is being fetched.
 217     */
 218    virtual string DescURI() = 0;
 219    /** \brief Short item description.
 220     *
 221     *  \return a brief description of the object being fetched.
 222     */
 223    virtual string ShortDesc() {return DescURI();}
 224
 225    /** \brief Invoked by the worker when the download is completely done. */
 226    virtual void Finished() {};
 227
 228    /** \brief MD5Sum.
 229     *
 230     *  \return the MD5Sum of this object, if applicable; otherwise, an
 231     *  empty string.
 232     */
 233    virtual string MD5Sum() {return string();};
 234
 235    /** \return the acquire process with which this item is associated. */
 236    pkgAcquire *GetOwner() {return Owner;};
 237
 238    /** \return \b true if this object is being fetched from a trusted source. */
 239    virtual bool IsTrusted() {return false;};
 240
 241    /** \brief Initialize an item.
 242     *
 243     *  Adds the item to the list of items known to the acquire
 244     *  process, but does not place it into any fetch queues (you must
 245     *  manually invoke QueueURI() to do so).
 246     *
 247     *  Initializes all fields of the item other than Owner to 0,
 248     *  false, or the empty string.
 249     *
 250     *  \param Owner The new owner of this item.
 251     */
 252    Item(pkgAcquire *Owner);
 253
 254    /** \brief Remove this item from its owner's queue by invoking
 255     *  pkgAcquire::Remove.
 256     */
 257    virtual ~Item();
 258 };
 259
 260 /** \brief Information about an index patch (aka diff). */
 261 struct DiffInfo {
 262    /** The filename of the diff. */
 263    string file;
 264
 265    /** The sha1 hash of the diff. */
 266    string sha1;
 267
 268    /** The size of the diff. */
 269    unsigned long size;
 270 };
 271
 272 /** \brief An item that is responsible for fetching an index file of
 273  *  package list diffs and starting the package list's download.
 274  *
 275  *  This item downloads the Index file and parses it, then enqueues
 276  *  additional downloads of either the individual patches (using
 277  *  pkgAcqIndexDiffs) or the entire Packages file (using pkgAcqIndex).
 278  *
 279  *  \sa pkgAcqIndexDiffs, pkgAcqIndex
 280  */
 281 class pkgAcqDiffIndex : public pkgAcquire::Item
 282 {
 283  protected:
 284    /** \brief If \b true, debugging information will be written to std::clog. */
 285    bool Debug;
 286
 287    /** \brief The item that is currently being downloaded. */
 288    pkgAcquire::ItemDesc Desc;
 289
 290    /** \brief The URI of the index file to recreate at our end (either
 291     *  by downloading it or by applying partial patches).
 292     */
 293    string RealURI;
 294
 295    /** \brief The MD5Sum that the real index file should have after
 296     *  all patches have been applied.
 297     */
 298    string ExpectedMD5;
 299
 300    /** \brief The index file which will be patched to generate the new
 301     *  file.
 302     */
 303    string CurrentPackagesFile;
 304
 305    /** \brief A description of the Packages file (stored in
 306     *  pkgAcquire::ItemDesc::Description).
 307     */
 308    string Description;
 309
 310  public:
 311    // Specialized action members
 312    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 313    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 314                      pkgAcquire::MethodConfig *Cnf);
 315    virtual string DescURI() {return RealURI + "Index";};
 316    virtual string Custom600Headers();
 317
 318    /** \brief Parse the Index file for a set of Packages diffs.
 319     *
 320     *  Parses the Index file and creates additional download items as
 321     *  necessary.
 322     *
 323     *  \param IndexDiffFile The name of the Index file.
 324     *
 325     *  \return \b true if the Index file was successfully parsed, \b
 326     *  false otherwise.
 327     */
 328    bool ParseDiffIndex(string IndexDiffFile);
 329
 330
 331    /** \brief Create a new pkgAcqDiffIndex.
 332     *
 333     *  \param Owner The Acquire object that owns this item.
 334     *
 335     *  \param URI The URI of the list file to download.
 336     *
 337     *  \param URIDesc A long description of the list file to download.
 338     *
 339     *  \param ShortDesc A short description of the list file to download.
 340     *
 341     *  \param ExpectedMD5 The list file's MD5 signature.
 342     */
 343    pkgAcqDiffIndex(pkgAcquire *Owner,string URI,string URIDesc,
 344                    string ShortDesc, string ExpectedMD5);
 345 };
 346
 347 /** \brief An item that is responsible for fetching all the patches
 348  *  that need to be applied to a given package index file.
 349  *
 350  *  After downloading and applying a single patch, this item will
 351  *  enqueue a new pkgAcqIndexDiffs to download and apply the remaining
 352  *  patches.  If no patch can be found that applies to an intermediate
 353  *  file or if one of the patches cannot be downloaded, falls back to
 354  *  downloading the entire package index file using pkgAcqIndex.
 355  *
 356  *  \sa pkgAcqDiffIndex, pkgAcqIndex
 357  */
 358 class pkgAcqIndexDiffs : public pkgAcquire::Item
 359 {
 360    private:
 361
 362    /** \brief Queue up the next diff download.
 363     *
 364     *  Search for the next available diff that applies to the file
 365     *  that currently exists on disk, and enqueue it by calling
 366     *  QueueURI().
 367     *
 368     *  \return \b true if an applicable diff was found, \b false
 369     *  otherwise.
 370     */
 371    bool QueueNextDiff();
 372
 373    /** \brief Handle tasks that must be performed after the item
 374     *  finishes downloading.
 375     *
 376     *  Dequeues the item and checks the resulting file's md5sum
 377     *  against ExpectedMD5 after the last patch was applied.
 378     *  There is no need to check the md5/sha1 after a "normal"
 379     *  patch because QueueNextDiff() will check the sha1 later.
 380     *
 381     *  \param allDone If \b true, the file was entirely reconstructed,
 382     *  and its md5sum is verified.
 383     */
 384    void Finish(bool allDone=false);
 385
 386    protected:
 387
 388    /** \brief If \b true, debugging output will be written to
 389     *  std::clog.
 390     */
 391    bool Debug;
 392
 393    /** \brief A description of the item that is currently being
 394     *  downloaded.
 395     */
 396    pkgAcquire::ItemDesc Desc;
 397
 398    /** \brief The URI of the package index file that is being
 399     *  reconstructed.
 400     */
 401    string RealURI;
 402
 403    /** \brief The MD5Sum of the package index file that is being
 404     *  reconstructed.
 405     */
 406    string ExpectedMD5;
 407
 408    /** A description of the file being downloaded. */
 409    string Description;
 410
 411    /** The patches that remain to be downloaded, including the patch
 412     *  being downloaded right now.  This list should be ordered so
 413     *  that each diff appears before any diff that depends on it.
 414     *
 415     *  \todo These are indexed by sha1sum; why not use some sort of
 416     *  dictionary instead of relying on ordering and stripping them
 417     *  off the front?
 418     */
 419    vector<DiffInfo> available_patches;
 420    /** The current status of this patch. */
 421    enum DiffState
 422      {
 423         /** \brief The diff is in an unknown state. */
 424          StateFetchUnkown,
 425
 426          /** \brief The diff is currently being fetched. */
 427          StateFetchDiff,
 428
 429          /** \brief The diff is currently being uncompressed. */
 430          StateUnzipDiff,
 431
 432          /** \brief The diff is currently being applied. */
 433          StateApplyDiff
 434    } State;
 435
 436    public:
 437
 438    /** \brief Called when the patch file failed to be downloaded.
 439     *
 440     *  This method will fall back to downloading the whole index file
 441     *  outright; its arguments are ignored.
 442     */
 443    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 444
 445    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 446                      pkgAcquire::MethodConfig *Cnf);
 447    virtual string DescURI() {return RealURI + "Index";};
 448
 449    /** \brief Create an index diff item.
 450     *
 451     *  After filling in its basic fields, this invokes Finish(true) if
 452     *  #diffs is empty, or QueueNextDiff() otherwise.
 453     *
 454     *  \param Owner The pkgAcquire object that owns this item.
 455     *
 456     *  \param URI The URI of the package index file being
 457     *  reconstructed.
 458     *
 459     *  \param URIDesc A long description of this item.
 460     *
 461     *  \param ShortDesc A brief description of this item.
 462     *
 463     *  \param ExpectedMD5 The expected md5sum of the completely
 464     *  reconstructed package index file; the index file will be tested
 465     *  against this value when it is entirely reconstructed.
 466     *
 467     *  \param diffs The remaining diffs from the index of diffs.  They
 468     *  should be ordered so that each diff appears before any diff
 469     *  that depends on it.
 470     */
 471    pkgAcqIndexDiffs(pkgAcquire *Owner,string URI,string URIDesc,
 472                     string ShortDesc, string ExpectedMD5,
 473                     vector<DiffInfo> diffs=vector<DiffInfo>());
 474 };
 475
 476 /** \brief An acquire item that is responsible for fetching an index
 477  *  file (e.g., Packages or Sources).
 478  *
 479  *  \sa pkgAcqDiffIndex, pkgAcqIndexDiffs, pkgAcqIndexTrans
 480  *
 481  *  \todo Why does pkgAcqIndex have protected members?
 482  */
 483 class pkgAcqIndex : public pkgAcquire::Item
 484 {
 485    protected:
 486
 487    /** \brief If \b true, the index file has been decompressed. */
 488    bool Decompression;
 489
 490    /** \brief If \b true, the partially downloaded file will be
 491     *  removed when the download completes.
 492     */
 493    bool Erase;
 494
 495    /** \brief The download request that is currently being
 496     *   processed.
 497     */
 498    pkgAcquire::ItemDesc Desc;
 499
 500    /** \brief The object that is actually being fetched (minus any
 501     *  compression-related extensions).
 502     */
 503    string RealURI;
 504
 505    /** \brief The expected md5sum of the decompressed index file. */
 506    string ExpectedMD5;
 507
 508    /** \brief The compression-related file extension that is being
 509     *  added to the downloaded file (e.g., ".gz" or ".bz2").
 510     */
 511    string CompressionExtension;
 512
 513    public:
 514
 515    // Specialized action members
 516    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 517    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 518                      pkgAcquire::MethodConfig *Cnf);
 519    virtual string Custom600Headers();
 520    virtual string DescURI() {return RealURI + CompressionExtension;};
 521
 522    /** \brief Create a pkgAcqIndex.
 523     *
 524     *  \param Owner The pkgAcquire object with which this item is
 525     *  associated.
 526     *
 527     *  \param URI The URI of the index file that is to be downloaded.
 528     *
 529     *  \param URIDesc A "URI-style" description of this index file.
 530     *
 531     *  \param ShortDesc A brief description of this index file.
 532     *
 533     *  \param ExpectedMD5 The expected md5sum of this index file.
 534     *
 535     *  \param compressExt The compression-related extension with which
 536     *  this index file should be downloaded, or "" to autodetect
 537     *  (".bz2" is used if bzip2 is installed, ".gz" otherwise).
 538     */
 539    pkgAcqIndex(pkgAcquire *Owner,string URI,string URIDesc,
 540                string ShortDesc, string ExpectedMD5, string compressExt="");
 541 };
 542
 543 /** \brief An acquire item that is responsible for fetching a
 544  *  translated index file.
 545  *
 546  *  The only difference from pkgAcqIndex is that transient failures
 547  *  are suppressed: no error occurs if the translated index file is
 548  *  missing.
 549  */
 550 class pkgAcqIndexTrans : public pkgAcqIndex
 551 {
 552    public:
 553
 554    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 555
 556    /** \brief Create a pkgAcqIndexTrans.
 557     *
 558     *  \param Owner The pkgAcquire object with which this item is
 559     *  associated.
 560     *
 561     *  \param URI The URI of the index file that is to be downloaded.
 562     *
 563     *  \param URIDesc A "URI-style" description of this index file.
 564     *
 565     *  \param ShortDesc A brief description of this index file.
 566     *
 567     *  \param ExpectedMD5 The expected md5sum of this index file.
 568     *
 569     *  \param compressExt The compression-related extension with which
 570     *  this index file should be downloaded, or "" to autodetect
 571     *  (".bz2" is used if bzip2 is installed, ".gz" otherwise).
 572     */
 573    pkgAcqIndexTrans(pkgAcquire *Owner,string URI,string URIDesc,
 574                     string ShortDesc);
 575 };
 576
 577 /** \brief Information about an index file. */
 578 struct IndexTarget
 579 {
 580    /** \brief A URI from which the index file can be downloaded. */
 581    string URI;
 582
 583    /** \brief A description of the index file. */
 584    string Description;
 585
 586    /** \brief A shorter description of the index file. */
 587    string ShortDesc;
 588
 589    /** \brief The key by which this index file should be
 590     *  looked up within the meta signature file.
 591     */
 592    string MetaKey;
 593 };
 594
 595 /** \brief An acquire item that downloads the detached signature
 596  *  of a meta-index (Release) file, then queues up the release
 597  *  file itself.
 598  *
 599  *  \todo Why protected members?
 600  *
 601  *  \sa pkgAcqMetaIndex
 602  */
 603 class pkgAcqMetaSig : public pkgAcquire::Item
 604 {
 605    protected:
 606    /** \brief The fetch request that is currently being processed. */
 607    pkgAcquire::ItemDesc Desc;
 608
 609    /** \brief The URI of the signature file.  Unlike Desc.URI, this is
 610     *  never modified; it is used to determine the file that is being
 611     *  downloaded.
 612     */
 613    string RealURI;
 614
 615    /** \brief The URI of the meta-index file to be fetched after the signature. */
 616    string MetaIndexURI;
 617
 618    /** \brief A "URI-style" description of the meta-index file to be
 619     *  fetched after the signature.
 620     */
 621    string MetaIndexURIDesc;
 622
 623    /** \brief A brief description of the meta-index file to be fetched
 624     *  after the signature.
 625     */
 626    string MetaIndexShortDesc;
 627
 628    /** \brief A package-system-specific parser for the meta-index file. */
 629    indexRecords* MetaIndexParser;
 630
 631    /** \brief The index files which should be looked up in the meta-index
 632     *  and then downloaded.
 633     *
 634     *  \todo Why a list of pointers instead of a list of structs?
 635     */
 636    const vector<struct IndexTarget*>* IndexTargets;
 637
 638    public:
 639
 640    // Specialized action members
 641    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 642    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 643                      pkgAcquire::MethodConfig *Cnf);
 644    virtual string Custom600Headers();
 645    virtual string DescURI() {return RealURI; };
 646
 647    /** \brief Create a new pkgAcqMetaSig. */
 648    pkgAcqMetaSig(pkgAcquire *Owner,string URI,string URIDesc, string ShortDesc,
 649                  string MetaIndexURI, string MetaIndexURIDesc, string MetaIndexShortDesc,
 650                  const vector<struct IndexTarget*>* IndexTargets,
 651                  indexRecords* MetaIndexParser);
 652 };
 653
 654 /** \brief An item that is responsible for downloading the meta-index
 655  *  file (i.e., Release) itself and verifying its signature.
 656  *
 657  *  Once the download and verification are complete, the downloads of
 658  *  the individual index files are queued up using pkgAcqDiffIndex.
 659  *  If the meta-index file had a valid signature, the expected md5sums
 660  *  of the index files will be the md5sums listed in the meta-index;
 661  *  otherwise, the expected md5sums will be "" (causing the
 662  *  authentication of the index files to be bypassed).
 663  */
 664 class pkgAcqMetaIndex : public pkgAcquire::Item
 665 {
 666    protected:
 667    /** \brief The fetch command that is currently being processed. */
 668    pkgAcquire::ItemDesc Desc;
 669
 670    /** \brief The URI that is actually being downloaded; never
 671     *  modified by pkgAcqMetaIndex.
 672     */
 673    string RealURI;
 674
 675    /** \brief The file in which the signature for this index was stored.
 676     *
 677     *  If empty, the signature and the md5sums of the individual
 678     *  indices will not be checked.
 679     */
 680    string SigFile;
 681
 682    /** \brief The index files to download. */
 683    const vector<struct IndexTarget*>* IndexTargets;
 684
 685    /** \brief The parser for the meta-index file. */
 686    indexRecords* MetaIndexParser;
 687
 688    /** \brief If \b true, the index's signature is currently being verified.
 689     */
 690    bool AuthPass;
 691    // required to deal gracefully with problems caused by incorrect ims hits
 692    bool IMSHit;
 693
 694    /** \brief Check that the release file is a release file for the
 695     *  correct distribution.
 696     *
 697     *  \return \b true if no fatal errors were encountered.
 698     */
 699    bool VerifyVendor(string Message);
 700
 701    /** \brief Called when a file is finished being retrieved.
 702     *
 703     *  If the file was not downloaded to DestFile, a copy process is
 704     *  set up to copy it to DestFile; otherwise, Complete is set to \b
 705     *  true and the file is moved to its final location.
 706     *
 707     *  \param Message The message block received from the fetch
 708     *  subprocess.
 709     */
 710    void RetrievalDone(string Message);
 711
 712    /** \brief Called when authentication succeeded.
 713     *
 714     *  Sanity-checks the authenticated file, queues up the individual
 715     *  index files for download, and saves the signature in the lists
 716     *  directory next to the authenticated list file.
 717     *
 718     *  \param Message The message block received from the fetch
 719     *  subprocess.
 720     */
 721    void AuthDone(string Message);
 722
 723    /** \brief Starts downloading the individual index files.
 724     *
 725     *  \param verify If \b true, only indices whose expected md5sum
 726     *  can be determined from the meta-index will be downloaded, and
 727     *  the md5sums of indices will be checked (reporting
 728     *  #StatAuthError if there is a mismatch).  If verify is \b false,
 729     *  no md5sum checking will be performed.
 730     */
 731    void QueueIndexes(bool verify);
 732
 733    public:
 734
 735    // Specialized action members
 736    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 737    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 738                      pkgAcquire::MethodConfig *Cnf);
 739    virtual string Custom600Headers();
 740    virtual string DescURI() {return RealURI; };
 741
 742    /** \brief Create a new pkgAcqMetaIndex. */
 743    pkgAcqMetaIndex(pkgAcquire *Owner,
 744                    string URI,string URIDesc, string ShortDesc,
 745                    string SigFile,
 746                    const vector<struct IndexTarget*>* IndexTargets,
 747                    indexRecords* MetaIndexParser);
 748 };
 749
 750 /** \brief An item that is responsible for fetching a package file.
 751  *
 752  *  If the package file already exists in the cache, nothing will be
 753  *  done.
 754  */
 755 class pkgAcqArchive : public pkgAcquire::Item
 756 {
 757    protected:
 758    /** \brief The package version being fetched. */
 759    pkgCache::VerIterator Version;
 760
 761    /** \brief The fetch command that is currently being processed. */
 762    pkgAcquire::ItemDesc Desc;
 763
 764    /** \brief The list of sources from which to pick archives to
 765     *  download this package from.
 766     */
 767    pkgSourceList *Sources;
 768
 769    /** \brief A package records object, used to look up the file
 770     *  corresponding to each version of the package.
 771     */
 772    pkgRecords *Recs;
 773
 774    /** \brief The md5sum of this package. */
 775    string MD5;
 776
 777    /** \brief A location in which the actual filename of the package
 778     *  should be stored.
 779     */
 780    string &StoreFilename;
 781
 782    /** \brief The next file for this version to try to download. */
 783    pkgCache::VerFileIterator Vf;
 784
 785    /** \brief How many (more) times to try to find a new source from
 786     *  which to download this package version if it fails.
 787     *
 788     *  Set from Acquire::Retries.
 789     */
 790    unsigned int Retries;
 791
 792    /** \brief \b true if this version file is being downloaded from a
 793     *  trusted source.
 794     */
 795    bool Trusted;
 796
 797    /** \brief Queue up the next available file for this version. */
 798    bool QueueNext();
 799
 800    public:
 801
 802    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 803    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 804                      pkgAcquire::MethodConfig *Cnf);
 805    virtual string MD5Sum() {return MD5;};
 806    virtual string DescURI() {return Desc.URI;};
 807    virtual string ShortDesc() {return Desc.ShortDesc;};
 808    virtual void Finished();
 809
 810    virtual bool IsTrusted();
 811
 812    /** \brief Create a new pkgAcqArchive.
 813     *
 814     *  \param Owner The pkgAcquire object with which this item is
 815     *  associated.
 816     *
 817     *  \param Sources The sources from which to download version
 818     *  files.
 819     *
 820     *  \param Recs A package records object, used to look up the file
 821     *  corresponding to each version of the package.
 822     *
 823     *  \param Version The package version to download.
 824     *
 825     *  \param StoreFilename A location in which the actual filename of
 826     *  the package should be stored.  It will be set to a guessed
 827     *  basename in the constructor, and filled in with a fully
 828     *  qualified filename once the download finishes.
 829     */
 830    pkgAcqArchive(pkgAcquire *Owner,pkgSourceList *Sources,
 831                  pkgRecords *Recs,pkgCache::VerIterator const &Version,
 832                  string &StoreFilename);
 833 };
 834
 835 /** \brief Retrieve an arbitrary file to the current directory.
 836  *
 837  *  The file is retrieved even if it is accessed via a URL type that
 838  *  normally is a NOP, such as "file".  If the download fails, the
 839  *  partial file is renamed to get a ".FAILED" extension.
 840  */
 841 class pkgAcqFile : public pkgAcquire::Item
 842 {
 843    /** \brief The currently active download process. */
 844    pkgAcquire::ItemDesc Desc;
 845
 846    /** \brief The md5sum of the file to download, if it is known. */
 847    string Md5Hash;
 848
 849    /** \brief How many times to retry the download, set from
 850     *  Acquire::Retries.
 851     */
 852    unsigned int Retries;
 853
 854    public:
 855
 856    // Specialized action members
 857    virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf);
 858    virtual void Done(string Message,unsigned long Size,string Md5Hash,
 859                      pkgAcquire::MethodConfig *Cnf);
 860    virtual string MD5Sum() {return Md5Hash;};
 861    virtual string DescURI() {return Desc.URI;};
 862
 863    /** \brief Create a new pkgAcqFile object.
 864     *
 865     *  \param Owner The pkgAcquire object with which this object is
 866     *  associated.
 867     *
 868     *  \param URI The URI to download.
 869     *
 870     *  \param MD5 The md5sum of the file to download, if it is known;
 871     *  otherwise "".
 872     *
 873     *  \param Size The size of the file to download, if it is known;
 874     *  otherwise 0.
 875     *
 876     *  \param Desc A description of the file being downloaded.
 877     *
 878     *  \param ShortDesc A brief description of the file being
 879     *  downloaded.
 880     *
 881     *  \param DestDir The directory the file should be downloaded into.
 882     *
 883     *  \param DestFilename The filename+path the file is downloaded to.
 884     *
 885     *
 886     * If DestFilename is empty, download to DestDir/<basename> if
 887     * DestDir is non-empty, $CWD/<basename> otherwise.  If
 888     * DestFilename is NOT empty, DestDir is ignored and DestFilename
 889     * is the absolute name to which the file should be downloaded.
 890     */
 891
 892    pkgAcqFile(pkgAcquire *Owner, string URI, string MD5, unsigned long Size,
 893               string Desc, string ShortDesc,
 894               const string &DestDir="", const string &DestFilename="");
 895 };
 896
 897 /** @} */
 898
 899 #endif