apt-pkg/acquire.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: acquire.cc,v 1.20 1998/12/05 04:19:03 jgg Exp $
   4 /* ######################################################################
   5
   6    Acquire - File Acquiration
   7
   8    The core element for the schedual system is the concept of a named
   9    queue. Each queue is unique and each queue has a name derived from the
  10    URI. The degree of paralization can be controled by how the queue
  11    name is derived from the URI.
  12
  13    ##################################################################### */
  14                                                                         /*}}}*/
  15 // Include Files                                                        /*{{{*/
  16 #ifdef __GNUG__
  17 #pragma implementation "apt-pkg/acquire.h"
  18 #endif
  19 #include <apt-pkg/acquire.h>
  20 #include <apt-pkg/acquire-item.h>
  21 #include <apt-pkg/acquire-worker.h>
  22 #include <apt-pkg/configuration.h>
  23 #include <apt-pkg/error.h>
  24 #include <strutl.h>
  25
  26 #include <dirent.h>
  27 #include <sys/time.h>
  28                                                                         /*}}}*/
  29
  30 // Acquire::pkgAcquire - Constructor                                    /*{{{*/
  31 // ---------------------------------------------------------------------
  32 /* We grab some runtime state from the configuration space */
  33 pkgAcquire::pkgAcquire(pkgAcquireStatus *Log) : Log(Log)
  34 {
  35    Queues = 0;
  36    Configs = 0;
  37    Workers = 0;
  38    ToFetch = 0;
  39    Running = false;
  40
  41    string Mode = _config->Find("Acquire::Queue-Mode","host");
  42    if (strcasecmp(Mode.c_str(),"host") == 0)
  43       QueueMode = QueueHost;
  44    if (strcasecmp(Mode.c_str(),"access") == 0)
  45       QueueMode = QueueAccess;
  46
  47    Debug = _config->FindB("Debug::pkgAcquire",false);
  48 }
  49                                                                         /*}}}*/
  50 // Acquire::~pkgAcquire - Destructor                                    /*{{{*/
  51 // ---------------------------------------------------------------------
  52 /* Free our memory, clean up the queues (destroy the workers) */
  53 pkgAcquire::~pkgAcquire()
  54 {
  55    while (Items.size() != 0)
  56       delete Items[0];
  57
  58    while (Configs != 0)
  59    {
  60       MethodConfig *Jnk = Configs;
  61       Configs = Configs->Next;
  62       delete Jnk;
  63    }
  64
  65    while (Queues != 0)
  66    {
  67       Queue *Jnk = Queues;
  68       Queues = Queues->Next;
  69       delete Jnk;
  70    }
  71 }
  72                                                                         /*}}}*/
  73 // Acquire::Add - Add a new item                                        /*{{{*/
  74 // ---------------------------------------------------------------------
  75 /* This puts an item on the acquire list. This list is mainly for tracking
  76    item status */
  77 void pkgAcquire::Add(Item *Itm)
  78 {
  79    Items.push_back(Itm);
  80 }
  81                                                                         /*}}}*/
  82 // Acquire::Remove - Remove a item                                      /*{{{*/
  83 // ---------------------------------------------------------------------
  84 /* Remove an item from the acquire list. This is usually not used.. */
  85 void pkgAcquire::Remove(Item *Itm)
  86 {
  87    for (vector<Item *>::iterator I = Items.begin(); I < Items.end(); I++)
  88    {
  89       if (*I == Itm)
  90          Items.erase(I);
  91    }
  92 }
  93                                                                         /*}}}*/
  94 // Acquire::Add - Add a worker                                          /*{{{*/
  95 // ---------------------------------------------------------------------
  96 /* A list of workers is kept so that the select loop can direct their FD
  97    usage. */
  98 void pkgAcquire::Add(Worker *Work)
  99 {
 100    Work->NextAcquire = Workers;
 101    Workers = Work;
 102 }
 103                                                                         /*}}}*/
 104 // Acquire::Remove - Remove a worker                                    /*{{{*/
 105 // ---------------------------------------------------------------------
 106 /* A worker has died. This can not be done while the select loop is running
 107    as it would require that RunFds could handling a changing list state and
 108    it cant.. */
 109 void pkgAcquire::Remove(Worker *Work)
 110 {
 111    if (Running == true)
 112       abort();
 113
 114    Worker **I = &Workers;
 115    for (; *I != 0;)
 116    {
 117       if (*I == Work)
 118          *I = (*I)->NextAcquire;
 119       else
 120          I = &(*I)->NextAcquire;
 121    }
 122 }
 123                                                                         /*}}}*/
 124 // Acquire::Enqueue - Queue an URI for fetching                         /*{{{*/
 125 // ---------------------------------------------------------------------
 126 /* This is the entry point for an item. An item calls this function when
 127    it is construction which creates a queue (based on the current queue
 128    mode) and puts the item in that queue. If the system is running then
 129    the queue might be started. */
 130 void pkgAcquire::Enqueue(ItemDesc &Item)
 131 {
 132    // Determine which queue to put the item in
 133    const MethodConfig *Config;
 134    string Name = QueueName(Item.URI,Config);
 135    if (Name.empty() == true)
 136       return;
 137
 138    // Find the queue structure
 139    Queue *I = Queues;
 140    for (; I != 0 && I->Name != Name; I = I->Next);
 141    if (I == 0)
 142    {
 143       I = new Queue(Name,this);
 144       I->Next = Queues;
 145       Queues = I;
 146
 147       if (Running == true)
 148          I->Startup();
 149    }
 150
 151    // See if this is a local only URI
 152    if (Config->LocalOnly == true && Item.Owner->Complete == false)
 153       Item.Owner->Local = true;
 154    Item.Owner->Status = Item::StatIdle;
 155
 156    // Queue it into the named queue
 157    I->Enqueue(Item);
 158    ToFetch++;
 159
 160    // Some trace stuff
 161    if (Debug == true)
 162    {
 163       clog << "Fetching " << Item.URI << endl;
 164       clog << " to " << Item.Owner->DestFile << endl;
 165       clog << " Queue is: " << Name << endl;
 166    }
 167 }
 168                                                                         /*}}}*/
 169 // Acquire::Dequeue - Remove an item from all queues                    /*{{{*/
 170 // ---------------------------------------------------------------------
 171 /* This is called when an item is finished being fetched. It removes it
 172    from all the queues */
 173 void pkgAcquire::Dequeue(Item *Itm)
 174 {
 175    Queue *I = Queues;
 176    bool Res = false;
 177    for (; I != 0; I = I->Next)
 178       Res |= I->Dequeue(Itm);
 179
 180    if (Debug == true)
 181       clog << "Dequeuing " << Itm->DestFile << endl;
 182    if (Res == true)
 183       ToFetch--;
 184 }
 185                                                                         /*}}}*/
 186 // Acquire::QueueName - Return the name of the queue for this URI       /*{{{*/
 187 // ---------------------------------------------------------------------
 188 /* The string returned depends on the configuration settings and the
 189    method parameters. Given something like http://foo.org/bar it can
 190    return http://foo.org or http */
 191 string pkgAcquire::QueueName(string Uri,MethodConfig const *&Config)
 192 {
 193    URI U(Uri);
 194
 195    Config = GetConfig(U.Access);
 196    if (Config == 0)
 197       return string();
 198
 199    /* Single-Instance methods get exactly one queue per URI. This is
 200       also used for the Access queue method  */
 201    if (Config->SingleInstance == true || QueueMode == QueueAccess)
 202        return U.Access;
 203
 204    return U.Access + ':' + U.Host;
 205 }
 206                                                                         /*}}}*/
 207 // Acquire::GetConfig - Fetch the configuration information             /*{{{*/
 208 // ---------------------------------------------------------------------
 209 /* This locates the configuration structure for an access method. If
 210    a config structure cannot be found a Worker will be created to
 211    retrieve it */
 212 pkgAcquire::MethodConfig *pkgAcquire::GetConfig(string Access)
 213 {
 214    // Search for an existing config
 215    MethodConfig *Conf;
 216    for (Conf = Configs; Conf != 0; Conf = Conf->Next)
 217       if (Conf->Access == Access)
 218          return Conf;
 219
 220    // Create the new config class
 221    Conf = new MethodConfig;
 222    Conf->Access = Access;
 223    Conf->Next = Configs;
 224    Configs = Conf;
 225
 226    // Create the worker to fetch the configuration
 227    Worker Work(Conf);
 228    if (Work.Start() == false)
 229       return 0;
 230
 231    return Conf;
 232 }
 233                                                                         /*}}}*/
 234 // Acquire::SetFds - Deal with readable FDs                             /*{{{*/
 235 // ---------------------------------------------------------------------
 236 /* Collect FDs that have activity monitors into the fd sets */
 237 void pkgAcquire::SetFds(int &Fd,fd_set *RSet,fd_set *WSet)
 238 {
 239    for (Worker *I = Workers; I != 0; I = I->NextAcquire)
 240    {
 241       if (I->InReady == true && I->InFd >= 0)
 242       {
 243          if (Fd < I->InFd)
 244             Fd = I->InFd;
 245          FD_SET(I->InFd,RSet);
 246       }
 247       if (I->OutReady == true && I->OutFd >= 0)
 248       {
 249          if (Fd < I->OutFd)
 250             Fd = I->OutFd;
 251          FD_SET(I->OutFd,WSet);
 252       }
 253    }
 254 }
 255                                                                         /*}}}*/
 256 // Acquire::RunFds - Deal with active FDs                               /*{{{*/
 257 // ---------------------------------------------------------------------
 258 /* Dispatch active FDs over to the proper workers. It is very important
 259    that a worker never be erased while this is running! The queue class
 260    should never erase a worker except during shutdown processing. */
 261 void pkgAcquire::RunFds(fd_set *RSet,fd_set *WSet)
 262 {
 263    for (Worker *I = Workers; I != 0; I = I->NextAcquire)
 264    {
 265       if (I->InFd >= 0 && FD_ISSET(I->InFd,RSet) != 0)
 266          I->InFdReady();
 267       if (I->OutFd >= 0 && FD_ISSET(I->OutFd,WSet) != 0)
 268          I->OutFdReady();
 269    }
 270 }
 271                                                                         /*}}}*/
 272 // Acquire::Run - Run the fetch sequence                                /*{{{*/
 273 // ---------------------------------------------------------------------
 274 /* This runs the queues. It manages a select loop for all of the
 275    Worker tasks. The workers interact with the queues and items to
 276    manage the actual fetch. */
 277 bool pkgAcquire::Run()
 278 {
 279    Running = true;
 280
 281    for (Queue *I = Queues; I != 0; I = I->Next)
 282       I->Startup();
 283
 284    if (Log != 0)
 285       Log->Start();
 286
 287    // Run till all things have been acquired
 288    struct timeval tv;
 289    tv.tv_sec = 0;
 290    tv.tv_usec = 500000;
 291    while (ToFetch > 0)
 292    {
 293       fd_set RFds;
 294       fd_set WFds;
 295       int Highest = 0;
 296       FD_ZERO(&RFds);
 297       FD_ZERO(&WFds);
 298       SetFds(Highest,&RFds,&WFds);
 299
 300       int Res = select(Highest+1,&RFds,&WFds,0,&tv);
 301       if (Res < 0)
 302       {
 303          _error->Errno("select","Select has failed");
 304          break;
 305       }
 306
 307       RunFds(&RFds,&WFds);
 308       if (_error->PendingError() == true)
 309          break;
 310
 311       // Timeout, notify the log class
 312       if (Res == 0 || (Log != 0 && Log->Update == true))
 313       {
 314          tv.tv_usec = 500000;
 315          for (Worker *I = Workers; I != 0; I = I->NextAcquire)
 316             I->Pulse();
 317          if (Log != 0)
 318             Log->Pulse(this);
 319       }
 320    }
 321
 322    if (Log != 0)
 323       Log->Stop();
 324
 325    // Shut down the acquire bits
 326    Running = false;
 327    for (Queue *I = Queues; I != 0; I = I->Next)
 328       I->Shutdown();
 329
 330    return !_error->PendingError();
 331 }
 332                                                                         /*}}}*/
 333 // Acquire::Bump - Called when an item is dequeued                      /*{{{*/
 334 // ---------------------------------------------------------------------
 335 /* This routine bumps idle queues in hopes that they will be able to fetch
 336    the dequeued item */
 337 void pkgAcquire::Bump()
 338 {
 339    for (Queue *I = Queues; I != 0; I = I->Next)
 340       I->Bump();
 341 }
 342                                                                         /*}}}*/
 343 // Acquire::WorkerStep - Step to the next worker                        /*{{{*/
 344 // ---------------------------------------------------------------------
 345 /* Not inlined to advoid including acquire-worker.h */
 346 pkgAcquire::Worker *pkgAcquire::WorkerStep(Worker *I)
 347 {
 348    return I->NextAcquire;
 349 };
 350                                                                         /*}}}*/
 351 // Acquire::Clean - Cleans a directory                                  /*{{{*/
 352 // ---------------------------------------------------------------------
 353 /* This is a bit simplistic, it looks at every file in the dir and sees
 354    if it is part of the download set. */
 355 bool pkgAcquire::Clean(string Dir)
 356 {
 357    DIR *D = opendir(Dir.c_str());
 358    if (D == 0)
 359       return _error->Errno("opendir","Unable to read %s",Dir.c_str());
 360
 361    string StartDir = SafeGetCWD();
 362    if (chdir(Dir.c_str()) != 0)
 363    {
 364       closedir(D);
 365       return _error->Errno("chdir","Unable to change to ",Dir.c_str());
 366    }
 367
 368    for (struct dirent *Dir = readdir(D); Dir != 0; Dir = readdir(D))
 369    {
 370       // Skip some files..
 371       if (strcmp(Dir->d_name,"lock") == 0 ||
 372           strcmp(Dir->d_name,"partial") == 0 ||
 373           strcmp(Dir->d_name,".") == 0 ||
 374           strcmp(Dir->d_name,"..") == 0)
 375          continue;
 376
 377       // Look in the get list
 378       vector<Item *>::iterator I = Items.begin();
 379       for (; I != Items.end(); I++)
 380          if (flNotDir((*I)->DestFile) == Dir->d_name)
 381             break;
 382
 383       // Nothing found, nuke it
 384       if (I == Items.end())
 385          unlink(Dir->d_name);
 386    };
 387
 388    chdir(StartDir.c_str());
 389    closedir(D);
 390    return true;
 391 }
 392                                                                         /*}}}*/
 393 // Acquire::TotalNeeded - Number of bytes to fetch                      /*{{{*/
 394 // ---------------------------------------------------------------------
 395 /* This is the total number of bytes needed */
 396 unsigned long pkgAcquire::TotalNeeded()
 397 {
 398    unsigned long Total = 0;
 399    for (pkgAcquire::Item **I = ItemsBegin(); I != ItemsEnd(); I++)
 400       Total += (*I)->FileSize;
 401    return Total;
 402 }
 403                                                                         /*}}}*/
 404 // Acquire::FetchNeeded - Number of bytes needed to get                 /*{{{*/
 405 // ---------------------------------------------------------------------
 406 /* This is the number of bytes that is not local */
 407 unsigned long pkgAcquire::FetchNeeded()
 408 {
 409    unsigned long Total = 0;
 410    for (pkgAcquire::Item **I = ItemsBegin(); I != ItemsEnd(); I++)
 411       if ((*I)->Local == false)
 412          Total += (*I)->FileSize;
 413    return Total;
 414 }
 415                                                                         /*}}}*/
 416
 417 // Acquire::MethodConfig::MethodConfig - Constructor                    /*{{{*/
 418 // ---------------------------------------------------------------------
 419 /* */
 420 pkgAcquire::MethodConfig::MethodConfig()
 421 {
 422    SingleInstance = false;
 423    Pipeline = false;
 424    SendConfig = false;
 425    LocalOnly = false;
 426    Next = 0;
 427 }
 428                                                                         /*}}}*/
 429
 430 // Queue::Queue - Constructor                                           /*{{{*/
 431 // ---------------------------------------------------------------------
 432 /* */
 433 pkgAcquire::Queue::Queue(string Name,pkgAcquire *Owner) : Name(Name),
 434             Owner(Owner)
 435 {
 436    Items = 0;
 437    Next = 0;
 438    Workers = 0;
 439 }
 440                                                                         /*}}}*/
 441 // Queue::~Queue - Destructor                                           /*{{{*/
 442 // ---------------------------------------------------------------------
 443 /* */
 444 pkgAcquire::Queue::~Queue()
 445 {
 446    Shutdown();
 447
 448    while (Items != 0)
 449    {
 450       QItem *Jnk = Items;
 451       Items = Items->Next;
 452       delete Jnk;
 453    }
 454 }
 455                                                                         /*}}}*/
 456 // Queue::Enqueue - Queue an item to the queue                          /*{{{*/
 457 // ---------------------------------------------------------------------
 458 /* */
 459 void pkgAcquire::Queue::Enqueue(ItemDesc &Item)
 460 {
 461    QItem **I = &Items;
 462    for (; *I != 0; I = &(*I)->Next);
 463
 464    // Create a new item
 465    QItem *Itm = new QItem;
 466    *Itm = Item;
 467    Itm->Next = 0;
 468    *I = Itm;
 469
 470    Item.Owner->QueueCounter++;
 471    if (Items->Next == 0)
 472       Cycle();
 473 }
 474                                                                         /*}}}*/
 475 // Queue::Dequeue - Remove an item from the queue                       /*{{{*/
 476 // ---------------------------------------------------------------------
 477 /* We return true if we hit something*/
 478 bool pkgAcquire::Queue::Dequeue(Item *Owner)
 479 {
 480    bool Res = false;
 481
 482    QItem **I = &Items;
 483    for (; *I != 0;)
 484    {
 485       if ((*I)->Owner == Owner)
 486       {
 487          QItem *Jnk= *I;
 488          *I = (*I)->Next;
 489          Owner->QueueCounter--;
 490          delete Jnk;
 491          Res = true;
 492       }
 493       else
 494          I = &(*I)->Next;
 495    }
 496
 497    return Res;
 498 }
 499                                                                         /*}}}*/
 500 // Queue::Startup - Start the worker processes                          /*{{{*/
 501 // ---------------------------------------------------------------------
 502 /* */
 503 bool pkgAcquire::Queue::Startup()
 504 {
 505    Shutdown();
 506
 507    URI U(Name);
 508    pkgAcquire::MethodConfig *Cnf = Owner->GetConfig(U.Access);
 509    if (Cnf == 0)
 510       return false;
 511
 512    Workers = new Worker(this,Cnf,Owner->Log);
 513    Owner->Add(Workers);
 514    if (Workers->Start() == false)
 515       return false;
 516
 517    /* When pipelining we commit 10 items. This needs to change when we
 518       added other source retry to have cycle maintain a pipeline depth
 519       on its own. */
 520    if (Cnf->Pipeline == true)
 521    {
 522       bool Res = true;
 523       for (int I = 0; I != 10 && Res == true; I++)
 524          Res &= Cycle();
 525       return Res;
 526    }
 527
 528    return Cycle();
 529 }
 530                                                                         /*}}}*/
 531 // Queue::Shutdown - Shutdown the worker processes                      /*{{{*/
 532 // ---------------------------------------------------------------------
 533 /* */
 534 bool pkgAcquire::Queue::Shutdown()
 535 {
 536    // Delete all of the workers
 537    while (Workers != 0)
 538    {
 539       pkgAcquire::Worker *Jnk = Workers;
 540       Workers = Workers->NextQueue;
 541       Owner->Remove(Jnk);
 542       delete Jnk;
 543    }
 544
 545    return true;
 546 }
 547                                                                         /*}}}*/
 548 // Queue::Finditem - Find a URI in the item list                        /*{{{*/
 549 // ---------------------------------------------------------------------
 550 /* */
 551 pkgAcquire::Queue::QItem *pkgAcquire::Queue::FindItem(string URI,pkgAcquire::Worker *Owner)
 552 {
 553    for (QItem *I = Items; I != 0; I = I->Next)
 554       if (I->URI == URI && I->Worker == Owner)
 555          return I;
 556    return 0;
 557 }
 558                                                                         /*}}}*/
 559 // Queue::ItemDone - Item has been completed                            /*{{{*/
 560 // ---------------------------------------------------------------------
 561 /* The worker signals this which causes the item to be removed from the
 562    queue. If this is the last queue instance then it is removed from the
 563    main queue too.*/
 564 bool pkgAcquire::Queue::ItemDone(QItem *Itm)
 565 {
 566    if (Itm->Owner->QueueCounter <= 1)
 567       Owner->Dequeue(Itm->Owner);
 568    else
 569    {
 570       Dequeue(Itm->Owner);
 571       Owner->Bump();
 572    }
 573
 574    return Cycle();
 575 }
 576                                                                         /*}}}*/
 577 // Queue::Cycle - Queue new items into the method                       /*{{{*/
 578 // ---------------------------------------------------------------------
 579 /* This locates a new idle item and sends it to the worker */
 580 bool pkgAcquire::Queue::Cycle()
 581 {
 582    if (Items == 0 || Workers == 0)
 583       return true;
 584
 585    // Look for a queable item
 586    QItem *I = Items;
 587    for (; I != 0; I = I->Next)
 588       if (I->Owner->Status == pkgAcquire::Item::StatIdle)
 589          break;
 590
 591    // Nothing to do, queue is idle.
 592    if (I == 0)
 593       return true;
 594
 595    I->Worker = Workers;
 596    I->Owner->Status = pkgAcquire::Item::StatFetching;
 597    return Workers->QueueItem(I);
 598 }
 599                                                                         /*}}}*/
 600 // Queue::Bump - Fetch any pending objects if we are idle               /*{{{*/
 601 // ---------------------------------------------------------------------
 602 /* */
 603 void pkgAcquire::Queue::Bump()
 604 {
 605 }
 606                                                                         /*}}}*/
 607
 608 // AcquireStatus::pkgAcquireStatus - Constructor                        /*{{{*/
 609 // ---------------------------------------------------------------------
 610 /* */
 611 pkgAcquireStatus::pkgAcquireStatus()
 612 {
 613    Start();
 614 }
 615                                                                         /*}}}*/
 616 // AcquireStatus::Pulse - Called periodically                           /*{{{*/
 617 // ---------------------------------------------------------------------
 618 /* This computes some internal state variables for the derived classes to
 619    use. It generates the current downloaded bytes and total bytes to download
 620    as well as the current CPS estimate. */
 621 void pkgAcquireStatus::Pulse(pkgAcquire *Owner)
 622 {
 623    TotalBytes = 0;
 624    CurrentBytes = 0;
 625    TotalItems = 0;
 626    CurrentItems = 0;
 627
 628    // Compute the total number of bytes to fetch
 629    unsigned int Unknown = 0;
 630    unsigned int Count = 0;
 631    for (pkgAcquire::Item **I = Owner->ItemsBegin(); I != Owner->ItemsEnd();
 632         I++, Count++)
 633    {
 634       TotalItems++;
 635       if ((*I)->Status == pkgAcquire::Item::StatDone)
 636          CurrentItems++;
 637
 638       // Totally ignore local items
 639       if ((*I)->Local == true)
 640          continue;
 641
 642       TotalBytes += (*I)->FileSize;
 643       if ((*I)->Complete == true)
 644          CurrentBytes += (*I)->FileSize;
 645       if ((*I)->FileSize == 0 && (*I)->Complete == false)
 646          Unknown++;
 647    }
 648
 649    // Compute the current completion
 650    for (pkgAcquire::Worker *I = Owner->WorkersBegin(); I != 0;
 651         I = Owner->WorkerStep(I))
 652       if (I->CurrentItem != 0 && I->CurrentItem->Owner->Complete == false)
 653          CurrentBytes += I->CurrentSize;
 654
 655    // Normalize the figures and account for unknown size downloads
 656    if (TotalBytes <= 0)
 657       TotalBytes = 1;
 658    if (Unknown == Count)
 659       TotalBytes = Unknown;
 660    else
 661       TotalBytes += TotalBytes/(Count - Unknown)*Unknown;
 662
 663    // Compute the CPS
 664    struct timeval NewTime;
 665    gettimeofday(&NewTime,0);
 666    if (NewTime.tv_sec - Time.tv_sec == 6 && NewTime.tv_usec > Time.tv_usec ||
 667        NewTime.tv_sec - Time.tv_sec > 6)
 668    {
 669       // Compute the delta time with full accuracy
 670       long usdiff = NewTime.tv_usec - Time.tv_usec;
 671       long sdiff = NewTime.tv_sec - Time.tv_sec;
 672
 673       // Borrow
 674       if (usdiff < 0)
 675       {
 676          usdiff += 1000000;
 677          sdiff--;
 678       }
 679
 680       // Compute the CPS value
 681       if (sdiff == 0 && usdiff == 0)
 682          CurrentCPS = 0;
 683       else
 684          CurrentCPS = (CurrentBytes - LastBytes)/(sdiff + usdiff/1000000.0);
 685       LastBytes = CurrentBytes;
 686       ElapsedTime = NewTime.tv_sec - StartTime.tv_sec;
 687       Time = NewTime;
 688    }
 689 }
 690                                                                         /*}}}*/
 691 // AcquireStatus::Start - Called when the download is started           /*{{{*/
 692 // ---------------------------------------------------------------------
 693 /* We just reset the counters */
 694 void pkgAcquireStatus::Start()
 695 {
 696    gettimeofday(&Time,0);
 697    gettimeofday(&StartTime,0);
 698    LastBytes = 0;
 699    CurrentCPS = 0;
 700    CurrentBytes = 0;
 701    TotalBytes = 0;
 702    FetchedBytes = 0;
 703    ElapsedTime = 0;
 704    TotalItems = 0;
 705    CurrentItems = 0;
 706 }
 707                                                                         /*}}}*/
 708 // AcquireStatus::Stop - Finished downloading                           /*{{{*/
 709 // ---------------------------------------------------------------------
 710 /* This accurately computes the elapsed time and the total overall CPS. */
 711 void pkgAcquireStatus::Stop()
 712 {
 713    // Compute the CPS and elapsed time
 714    struct timeval NewTime;
 715    gettimeofday(&NewTime,0);
 716
 717    // Compute the delta time with full accuracy
 718    long usdiff = NewTime.tv_usec - StartTime.tv_usec;
 719    long sdiff = NewTime.tv_sec - StartTime.tv_sec;
 720
 721    // Borrow
 722    if (usdiff < 0)
 723    {
 724       usdiff += 1000000;
 725       sdiff--;
 726    }
 727
 728    // Compute the CPS value
 729    if (sdiff == 0 && usdiff == 0)
 730       CurrentCPS = 0;
 731    else
 732       CurrentCPS = FetchedBytes/(sdiff + usdiff/1000000.0);
 733    LastBytes = CurrentBytes;
 734    ElapsedTime = sdiff;
 735 }
 736                                                                         /*}}}*/
 737 // AcquireStatus::Fetched - Called when a byte set has been fetched     /*{{{*/
 738 // ---------------------------------------------------------------------
 739 /* This is used to get accurate final transfer rate reporting. */
 740 void pkgAcquireStatus::Fetched(unsigned long Size,unsigned long Resume)
 741 {
 742    FetchedBytes += Size - Resume;
 743 }
 744                                                                         /*}}}*/