methods/http.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: http.cc,v 1.59 2004/05/08 19:42:35 mdz Exp $
   4 /* ######################################################################
   5
   6    HTTP Aquire Method - This is the HTTP aquire method for APT.
   7
   8    It uses HTTP/1.1 and many of the fancy options there-in, such as
   9    pipelining, range, if-range and so on.
  10
  11    It is based on a doubly buffered select loop. A groupe of requests are
  12    fed into a single output buffer that is constantly fed out the
  13    socket. This provides ideal pipelining as in many cases all of the
  14    requests will fit into a single packet. The input socket is buffered
  15    the same way and fed into the fd for the file (may be a pipe in future).
  16
  17    This double buffering provides fairly substantial transfer rates,
  18    compared to wget the http method is about 4% faster. Most importantly,
  19    when HTTP is compared with FTP as a protocol the speed difference is
  20    huge. In tests over the internet from two sites to llug (via ATM) this
  21    program got 230k/s sustained http transfer rates. FTP on the other
  22    hand topped out at 170k/s. That combined with the time to setup the
  23    FTP connection makes HTTP a vastly superior protocol.
  24
  25    ##################################################################### */
  26                                                                         /*}}}*/
  27 // Include Files                                                        /*{{{*/
  28 #include <apt-pkg/fileutl.h>
  29 #include <apt-pkg/acquire-method.h>
  30 #include <apt-pkg/error.h>
  31 #include <apt-pkg/hashes.h>
  32
  33 #include <sys/stat.h>
  34 #include <sys/time.h>
  35 #include <utime.h>
  36 #include <unistd.h>
  37 #include <signal.h>
  38 #include <stdio.h>
  39 #include <errno.h>
  40 #include <string.h>
  41 #include <iostream>
  42 #include <apti18n.h>
  43
  44 // Internet stuff
  45 #include <netdb.h>
  46
  47 #include "config.h"
  48 #include "connect.h"
  49 #include "rfc2553emu.h"
  50 #include "http.h"
  51
  52                                                                         /*}}}*/
  53 using namespace std;
  54
  55 string HttpMethod::FailFile;
  56 int HttpMethod::FailFd = -1;
  57 time_t HttpMethod::FailTime = 0;
  58 unsigned long PipelineDepth = 10;
  59 unsigned long TimeOut = 120;
  60 bool Debug = false;
  61
  62
  63 unsigned long CircleBuf::BwReadLimit=0;
  64 unsigned long CircleBuf::BwTickReadData=0;
  65 struct timeval CircleBuf::BwReadTick={0,0};
  66 const unsigned int CircleBuf::BW_HZ=10;
  67
  68 // CircleBuf::CircleBuf - Circular input buffer                         /*{{{*/
  69 // ---------------------------------------------------------------------
  70 /* */
  71 CircleBuf::CircleBuf(unsigned long Size) : Size(Size), Hash(0)
  72 {
  73    Buf = new unsigned char[Size];
  74    Reset();
  75
  76    CircleBuf::BwReadLimit = _config->FindI("Acquire::http::Dl-Limit",0)*1024;
  77 }
  78                                                                         /*}}}*/
  79 // CircleBuf::Reset - Reset to the default state                        /*{{{*/
  80 // ---------------------------------------------------------------------
  81 /* */
  82 void CircleBuf::Reset()
  83 {
  84    InP = 0;
  85    OutP = 0;
  86    StrPos = 0;
  87    MaxGet = (unsigned int)-1;
  88    OutQueue = string();
  89    if (Hash != 0)
  90    {
  91       delete Hash;
  92       Hash = new Hashes;
  93    }
  94 };
  95                                                                         /*}}}*/
  96 // CircleBuf::Read - Read from a FD into the circular buffer            /*{{{*/
  97 // ---------------------------------------------------------------------
  98 /* This fills up the buffer with as much data as is in the FD, assuming it
  99    is non-blocking.. */
 100 bool CircleBuf::Read(int Fd)
 101 {
 102    unsigned long BwReadMax;
 103
 104    while (1)
 105    {
 106       // Woops, buffer is full
 107       if (InP - OutP == Size)
 108          return true;
 109
 110       // what's left to read in this tick
 111       BwReadMax = CircleBuf::BwReadLimit/BW_HZ;
 112
 113       if(CircleBuf::BwReadLimit) {
 114          struct timeval now;
 115          gettimeofday(&now,0);
 116
 117          unsigned long d = (now.tv_sec-CircleBuf::BwReadTick.tv_sec)*1000000 +
 118             now.tv_usec-CircleBuf::BwReadTick.tv_usec;
 119          if(d > 1000000/BW_HZ) {
 120             CircleBuf::BwReadTick = now;
 121             CircleBuf::BwTickReadData = 0;
 122          }
 123
 124          if(CircleBuf::BwTickReadData >= BwReadMax) {
 125             usleep(1000000/BW_HZ);
 126             return true;
 127          }
 128       }
 129
 130       // Write the buffer segment
 131       int Res;
 132       if(CircleBuf::BwReadLimit) {
 133          Res = read(Fd,Buf + (InP%Size),
 134                     BwReadMax > LeftRead() ? LeftRead() : BwReadMax);
 135       } else
 136          Res = read(Fd,Buf + (InP%Size),LeftRead());
 137
 138       if(Res > 0 && BwReadLimit > 0)
 139          CircleBuf::BwTickReadData += Res;
 140
 141       if (Res == 0)
 142          return false;
 143       if (Res < 0)
 144       {
 145          if (errno == EAGAIN)
 146             return true;
 147          return false;
 148       }
 149
 150       if (InP == 0)
 151          gettimeofday(&Start,0);
 152       InP += Res;
 153    }
 154 }
 155                                                                         /*}}}*/
 156 // CircleBuf::Read - Put the string into the buffer                     /*{{{*/
 157 // ---------------------------------------------------------------------
 158 /* This will hold the string in and fill the buffer with it as it empties */
 159 bool CircleBuf::Read(string Data)
 160 {
 161    OutQueue += Data;
 162    FillOut();
 163    return true;
 164 }
 165                                                                         /*}}}*/
 166 // CircleBuf::FillOut - Fill the buffer from the output queue           /*{{{*/
 167 // ---------------------------------------------------------------------
 168 /* */
 169 void CircleBuf::FillOut()
 170 {
 171    if (OutQueue.empty() == true)
 172       return;
 173    while (1)
 174    {
 175       // Woops, buffer is full
 176       if (InP - OutP == Size)
 177          return;
 178
 179       // Write the buffer segment
 180       unsigned long Sz = LeftRead();
 181       if (OutQueue.length() - StrPos < Sz)
 182          Sz = OutQueue.length() - StrPos;
 183       memcpy(Buf + (InP%Size),OutQueue.c_str() + StrPos,Sz);
 184
 185       // Advance
 186       StrPos += Sz;
 187       InP += Sz;
 188       if (OutQueue.length() == StrPos)
 189       {
 190          StrPos = 0;
 191          OutQueue = "";
 192          return;
 193       }
 194    }
 195 }
 196                                                                         /*}}}*/
 197 // CircleBuf::Write - Write from the buffer into a FD                   /*{{{*/
 198 // ---------------------------------------------------------------------
 199 /* This empties the buffer into the FD. */
 200 bool CircleBuf::Write(int Fd)
 201 {
 202    while (1)
 203    {
 204       FillOut();
 205
 206       // Woops, buffer is empty
 207       if (OutP == InP)
 208          return true;
 209
 210       if (OutP == MaxGet)
 211          return true;
 212
 213       // Write the buffer segment
 214       int Res;
 215       Res = write(Fd,Buf + (OutP%Size),LeftWrite());
 216
 217       if (Res == 0)
 218          return false;
 219       if (Res < 0)
 220       {
 221          if (errno == EAGAIN)
 222             return true;
 223
 224          return false;
 225       }
 226
 227       if (Hash != 0)
 228          Hash->Add(Buf + (OutP%Size),Res);
 229
 230       OutP += Res;
 231    }
 232 }
 233                                                                         /*}}}*/
 234 // CircleBuf::WriteTillEl - Write from the buffer to a string           /*{{{*/
 235 // ---------------------------------------------------------------------
 236 /* This copies till the first empty line */
 237 bool CircleBuf::WriteTillEl(string &Data,bool Single)
 238 {
 239    // We cheat and assume it is unneeded to have more than one buffer load
 240    for (unsigned long I = OutP; I < InP; I++)
 241    {
 242       if (Buf[I%Size] != '\n')
 243          continue;
 244       ++I;
 245
 246       if (Single == false)
 247       {
 248          if (I < InP  && Buf[I%Size] == '\r')
 249             ++I;
 250          if (I >= InP || Buf[I%Size] != '\n')
 251             continue;
 252          ++I;
 253       }
 254
 255       Data = "";
 256       while (OutP < I)
 257       {
 258          unsigned long Sz = LeftWrite();
 259          if (Sz == 0)
 260             return false;
 261          if (I - OutP < Sz)
 262             Sz = I - OutP;
 263          Data += string((char *)(Buf + (OutP%Size)),Sz);
 264          OutP += Sz;
 265       }
 266       return true;
 267    }
 268    return false;
 269 }
 270                                                                         /*}}}*/
 271 // CircleBuf::Stats - Print out stats information                       /*{{{*/
 272 // ---------------------------------------------------------------------
 273 /* */
 274 void CircleBuf::Stats()
 275 {
 276    if (InP == 0)
 277       return;
 278
 279    struct timeval Stop;
 280    gettimeofday(&Stop,0);
 281 /*   float Diff = Stop.tv_sec - Start.tv_sec +
 282              (float)(Stop.tv_usec - Start.tv_usec)/1000000;
 283    clog << "Got " << InP << " in " << Diff << " at " << InP/Diff << endl;*/
 284 }
 285                                                                         /*}}}*/
 286
 287 // ServerState::ServerState - Constructor                               /*{{{*/
 288 // ---------------------------------------------------------------------
 289 /* */
 290 ServerState::ServerState(URI Srv,HttpMethod *Owner) : Owner(Owner),
 291                         In(64*1024), Out(4*1024),
 292                         ServerName(Srv)
 293 {
 294    Reset();
 295 }
 296                                                                         /*}}}*/
 297 // ServerState::Open - Open a connection to the server                  /*{{{*/
 298 // ---------------------------------------------------------------------
 299 /* This opens a connection to the server. */
 300 bool ServerState::Open()
 301 {
 302    // Use the already open connection if possible.
 303    if (ServerFd != -1)
 304       return true;
 305
 306    Close();
 307    In.Reset();
 308    Out.Reset();
 309    Persistent = true;
 310
 311    // Determine the proxy setting
 312    if (getenv("http_proxy") == 0)
 313    {
 314       string DefProxy = _config->Find("Acquire::http::Proxy");
 315       string SpecificProxy = _config->Find("Acquire::http::Proxy::" + ServerName.Host);
 316       if (SpecificProxy.empty() == false)
 317       {
 318          if (SpecificProxy == "DIRECT")
 319             Proxy = "";
 320          else
 321             Proxy = SpecificProxy;
 322       }
 323       else
 324          Proxy = DefProxy;
 325    }
 326    else
 327       Proxy = getenv("http_proxy");
 328
 329    // Parse no_proxy, a , separated list of domains
 330    if (getenv("no_proxy") != 0)
 331    {
 332       if (CheckDomainList(ServerName.Host,getenv("no_proxy")) == true)
 333          Proxy = "";
 334    }
 335
 336    // Determine what host and port to use based on the proxy settings
 337    int Port = 0;
 338    string Host;
 339    if (Proxy.empty() == true || Proxy.Host.empty() == true)
 340    {
 341       if (ServerName.Port != 0)
 342          Port = ServerName.Port;
 343       Host = ServerName.Host;
 344    }
 345    else
 346    {
 347       if (Proxy.Port != 0)
 348          Port = Proxy.Port;
 349       Host = Proxy.Host;
 350    }
 351
 352    // Connect to the remote server
 353    if (Connect(Host,Port,"http",80,ServerFd,TimeOut,Owner) == false)
 354       return false;
 355
 356    return true;
 357 }
 358                                                                         /*}}}*/
 359 // ServerState::Close - Close a connection to the server                /*{{{*/
 360 // ---------------------------------------------------------------------
 361 /* */
 362 bool ServerState::Close()
 363 {
 364    close(ServerFd);
 365    ServerFd = -1;
 366    return true;
 367 }
 368                                                                         /*}}}*/
 369 // ServerState::RunHeaders - Get the headers before the data            /*{{{*/
 370 // ---------------------------------------------------------------------
 371 /* Returns 0 if things are OK, 1 if an IO error occursed and 2 if a header
 372    parse error occured */
 373 int ServerState::RunHeaders()
 374 {
 375    State = Header;
 376
 377    Owner->Status(_("Waiting for headers"));
 378
 379    Major = 0;
 380    Minor = 0;
 381    Result = 0;
 382    Size = 0;
 383    StartPos = 0;
 384    Encoding = Closes;
 385    HaveContent = false;
 386    time(&Date);
 387
 388    do
 389    {
 390       string Data;
 391       if (In.WriteTillEl(Data) == false)
 392          continue;
 393
 394       if (Debug == true)
 395          clog << Data;
 396
 397       for (string::const_iterator I = Data.begin(); I < Data.end(); I++)
 398       {
 399          string::const_iterator J = I;
 400          for (; J != Data.end() && *J != '\n' && *J != '\r';J++);
 401          if (HeaderLine(string(I,J)) == false)
 402             return 2;
 403          I = J;
 404       }
 405
 406       // 100 Continue is a Nop...
 407       if (Result == 100)
 408          continue;
 409
 410       // Tidy up the connection persistance state.
 411       if (Encoding == Closes && HaveContent == true)
 412          Persistent = false;
 413
 414       return 0;
 415    }
 416    while (Owner->Go(false,this) == true);
 417
 418    return 1;
 419 }
 420                                                                         /*}}}*/
 421 // ServerState::RunData - Transfer the data from the socket             /*{{{*/
 422 // ---------------------------------------------------------------------
 423 /* */
 424 bool ServerState::RunData()
 425 {
 426    State = Data;
 427
 428    // Chunked transfer encoding is fun..
 429    if (Encoding == Chunked)
 430    {
 431       while (1)
 432       {
 433          // Grab the block size
 434          bool Last = true;
 435          string Data;
 436          In.Limit(-1);
 437          do
 438          {
 439             if (In.WriteTillEl(Data,true) == true)
 440                break;
 441          }
 442          while ((Last = Owner->Go(false,this)) == true);
 443
 444          if (Last == false)
 445             return false;
 446
 447          // See if we are done
 448          unsigned long Len = strtol(Data.c_str(),0,16);
 449          if (Len == 0)
 450          {
 451             In.Limit(-1);
 452
 453             // We have to remove the entity trailer
 454             Last = true;
 455             do
 456             {
 457                if (In.WriteTillEl(Data,true) == true && Data.length() <= 2)
 458                   break;
 459             }
 460             while ((Last = Owner->Go(false,this)) == true);
 461             if (Last == false)
 462                return false;
 463             return !_error->PendingError();
 464          }
 465
 466          // Transfer the block
 467          In.Limit(Len);
 468          while (Owner->Go(true,this) == true)
 469             if (In.IsLimit() == true)
 470                break;
 471
 472          // Error
 473          if (In.IsLimit() == false)
 474             return false;
 475
 476          // The server sends an extra new line before the next block specifier..
 477          In.Limit(-1);
 478          Last = true;
 479          do
 480          {
 481             if (In.WriteTillEl(Data,true) == true)
 482                break;
 483          }
 484          while ((Last = Owner->Go(false,this)) == true);
 485          if (Last == false)
 486             return false;
 487       }
 488    }
 489    else
 490    {
 491       /* Closes encoding is used when the server did not specify a size, the
 492          loss of the connection means we are done */
 493       if (Encoding == Closes)
 494          In.Limit(-1);
 495       else
 496          In.Limit(Size - StartPos);
 497
 498       // Just transfer the whole block.
 499       do
 500       {
 501          if (In.IsLimit() == false)
 502             continue;
 503
 504          In.Limit(-1);
 505          return !_error->PendingError();
 506       }
 507       while (Owner->Go(true,this) == true);
 508    }
 509
 510    return Owner->Flush(this) && !_error->PendingError();
 511 }
 512                                                                         /*}}}*/
 513 // ServerState::HeaderLine - Process a header line                      /*{{{*/
 514 // ---------------------------------------------------------------------
 515 /* */
 516 bool ServerState::HeaderLine(string Line)
 517 {
 518    if (Line.empty() == true)
 519       return true;
 520
 521    // The http server might be trying to do something evil.
 522    if (Line.length() >= MAXLEN)
 523       return _error->Error(_("Got a single header line over %u chars"),MAXLEN);
 524
 525    string::size_type Pos = Line.find(' ');
 526    if (Pos == string::npos || Pos+1 > Line.length())
 527    {
 528       // Blah, some servers use "connection:closes", evil.
 529       Pos = Line.find(':');
 530       if (Pos == string::npos || Pos + 2 > Line.length())
 531          return _error->Error(_("Bad header line"));
 532       Pos++;
 533    }
 534
 535    // Parse off any trailing spaces between the : and the next word.
 536    string::size_type Pos2 = Pos;
 537    while (Pos2 < Line.length() && isspace(Line[Pos2]) != 0)
 538       Pos2++;
 539
 540    string Tag = string(Line,0,Pos);
 541    string Val = string(Line,Pos2);
 542
 543    if (stringcasecmp(Tag.c_str(),Tag.c_str()+4,"HTTP") == 0)
 544    {
 545       // Evil servers return no version
 546       if (Line[4] == '/')
 547       {
 548          if (sscanf(Line.c_str(),"HTTP/%u.%u %u %[^\n]",&Major,&Minor,
 549                     &Result,Code) != 4)
 550             return _error->Error(_("The HTTP server sent an invalid reply header"));
 551       }
 552       else
 553       {
 554          Major = 0;
 555          Minor = 9;
 556          if (sscanf(Line.c_str(),"HTTP %u %[^\n]",&Result,Code) != 2)
 557             return _error->Error(_("The HTTP server sent an invalid reply header"));
 558       }
 559
 560       /* Check the HTTP response header to get the default persistance
 561          state. */
 562       if (Major < 1)
 563          Persistent = false;
 564       else
 565       {
 566          if (Major == 1 && Minor <= 0)
 567             Persistent = false;
 568          else
 569             Persistent = true;
 570       }
 571
 572       return true;
 573    }
 574
 575    if (stringcasecmp(Tag,"Content-Length:") == 0)
 576    {
 577       if (Encoding == Closes)
 578          Encoding = Stream;
 579       HaveContent = true;
 580
 581       // The length is already set from the Content-Range header
 582       if (StartPos != 0)
 583          return true;
 584
 585       if (sscanf(Val.c_str(),"%lu",&Size) != 1)
 586          return _error->Error(_("The HTTP server sent an invalid Content-Length header"));
 587       return true;
 588    }
 589
 590    if (stringcasecmp(Tag,"Content-Type:") == 0)
 591    {
 592       HaveContent = true;
 593       return true;
 594    }
 595
 596    if (stringcasecmp(Tag,"Content-Range:") == 0)
 597    {
 598       HaveContent = true;
 599
 600       if (sscanf(Val.c_str(),"bytes %lu-%*u/%lu",&StartPos,&Size) != 2)
 601          return _error->Error(_("The HTTP server sent an invalid Content-Range header"));
 602       if ((unsigned)StartPos > Size)
 603          return _error->Error(_("This HTTP server has broken range support"));
 604       return true;
 605    }
 606
 607    if (stringcasecmp(Tag,"Transfer-Encoding:") == 0)
 608    {
 609       HaveContent = true;
 610       if (stringcasecmp(Val,"chunked") == 0)
 611          Encoding = Chunked;
 612       return true;
 613    }
 614
 615    if (stringcasecmp(Tag,"Connection:") == 0)
 616    {
 617       if (stringcasecmp(Val,"close") == 0)
 618          Persistent = false;
 619       if (stringcasecmp(Val,"keep-alive") == 0)
 620          Persistent = true;
 621       return true;
 622    }
 623
 624    if (stringcasecmp(Tag,"Last-Modified:") == 0)
 625    {
 626       if (StrToTime(Val,Date) == false)
 627          return _error->Error(_("Unknown date format"));
 628       return true;
 629    }
 630
 631    return true;
 632 }
 633                                                                         /*}}}*/
 634
 635 // HttpMethod::SendReq - Send the HTTP request                          /*{{{*/
 636 // ---------------------------------------------------------------------
 637 /* This places the http request in the outbound buffer */
 638 void HttpMethod::SendReq(FetchItem *Itm,CircleBuf &Out)
 639 {
 640    URI Uri = Itm->Uri;
 641
 642    // The HTTP server expects a hostname with a trailing :port
 643    char Buf[1000];
 644    string ProperHost = Uri.Host;
 645    if (Uri.Port != 0)
 646    {
 647       sprintf(Buf,":%u",Uri.Port);
 648       ProperHost += Buf;
 649    }
 650
 651    // Just in case.
 652    if (Itm->Uri.length() >= sizeof(Buf))
 653        abort();
 654
 655    /* Build the request. We include a keep-alive header only for non-proxy
 656       requests. This is to tweak old http/1.0 servers that do support keep-alive
 657       but not HTTP/1.1 automatic keep-alive. Doing this with a proxy server
 658       will glitch HTTP/1.0 proxies because they do not filter it out and
 659       pass it on, HTTP/1.1 says the connection should default to keep alive
 660       and we expect the proxy to do this */
 661    if (Proxy.empty() == true || Proxy.Host.empty())
 662       sprintf(Buf,"GET %s HTTP/1.1\r\nHost: %s\r\nConnection: keep-alive\r\n",
 663               QuoteString(Uri.Path,"~").c_str(),ProperHost.c_str());
 664    else
 665    {
 666       /* Generate a cache control header if necessary. We place a max
 667          cache age on index files, optionally set a no-cache directive
 668          and a no-store directive for archives. */
 669       sprintf(Buf,"GET %s HTTP/1.1\r\nHost: %s\r\n",
 670               Itm->Uri.c_str(),ProperHost.c_str());
 671       // only generate a cache control header if we actually want to
 672       // use a cache
 673       if (_config->FindB("Acquire::http::No-Cache",false) == false)
 674       {
 675          if (Itm->IndexFile == true)
 676             sprintf(Buf+strlen(Buf),"Cache-Control: max-age=%u\r\n",
 677                     _config->FindI("Acquire::http::Max-Age",0));
 678          else
 679          {
 680             if (_config->FindB("Acquire::http::No-Store",false) == true)
 681                strcat(Buf,"Cache-Control: no-store\r\n");
 682          }
 683       }
 684    }
 685    // generate a no-cache header if needed
 686    if (_config->FindB("Acquire::http::No-Cache",false) == true)
 687       strcat(Buf,"Cache-Control: no-cache\r\nPragma: no-cache\r\n");
 688
 689
 690    string Req = Buf;
 691
 692    // Check for a partial file
 693    struct stat SBuf;
 694    if (stat(Itm->DestFile.c_str(),&SBuf) >= 0 && SBuf.st_size > 0)
 695    {
 696       // In this case we send an if-range query with a range header
 697       sprintf(Buf,"Range: bytes=%li-\r\nIf-Range: %s\r\n",(long)SBuf.st_size - 1,
 698               TimeRFC1123(SBuf.st_mtime).c_str());
 699       Req += Buf;
 700    }
 701    else
 702    {
 703       if (Itm->LastModified != 0)
 704       {
 705          sprintf(Buf,"If-Modified-Since: %s\r\n",TimeRFC1123(Itm->LastModified).c_str());
 706          Req += Buf;
 707       }
 708    }
 709
 710    if (Proxy.User.empty() == false || Proxy.Password.empty() == false)
 711       Req += string("Proxy-Authorization: Basic ") +
 712           Base64Encode(Proxy.User + ":" + Proxy.Password) + "\r\n";
 713
 714    if (Uri.User.empty() == false || Uri.Password.empty() == false)
 715       Req += string("Authorization: Basic ") +
 716           Base64Encode(Uri.User + ":" + Uri.Password) + "\r\n";
 717
 718    Req += "User-Agent: Ubuntu APT-HTTP/1.3 ("VERSION")\r\n\r\n";
 719
 720    if (Debug == true)
 721       cerr << Req << endl;
 722
 723    Out.Read(Req);
 724 }
 725                                                                         /*}}}*/
 726 // HttpMethod::Go - Run a single loop                                   /*{{{*/
 727 // ---------------------------------------------------------------------
 728 /* This runs the select loop over the server FDs, Output file FDs and
 729    stdin. */
 730 bool HttpMethod::Go(bool ToFile,ServerState *Srv)
 731 {
 732    // Server has closed the connection
 733    if (Srv->ServerFd == -1 && (Srv->In.WriteSpace() == false ||
 734                                ToFile == false))
 735       return false;
 736
 737    fd_set rfds,wfds;
 738    FD_ZERO(&rfds);
 739    FD_ZERO(&wfds);
 740
 741    /* Add the server. We only send more requests if the connection will
 742       be persisting */
 743    if (Srv->Out.WriteSpace() == true && Srv->ServerFd != -1
 744        && Srv->Persistent == true)
 745       FD_SET(Srv->ServerFd,&wfds);
 746    if (Srv->In.ReadSpace() == true && Srv->ServerFd != -1)
 747       FD_SET(Srv->ServerFd,&rfds);
 748
 749    // Add the file
 750    int FileFD = -1;
 751    if (File != 0)
 752       FileFD = File->Fd();
 753
 754    if (Srv->In.WriteSpace() == true && ToFile == true && FileFD != -1)
 755       FD_SET(FileFD,&wfds);
 756
 757    // Add stdin
 758    FD_SET(STDIN_FILENO,&rfds);
 759
 760    // Figure out the max fd
 761    int MaxFd = FileFD;
 762    if (MaxFd < Srv->ServerFd)
 763       MaxFd = Srv->ServerFd;
 764
 765    // Select
 766    struct timeval tv;
 767    tv.tv_sec = TimeOut;
 768    tv.tv_usec = 0;
 769    int Res = 0;
 770    if ((Res = select(MaxFd+1,&rfds,&wfds,0,&tv)) < 0)
 771    {
 772       if (errno == EINTR)
 773          return true;
 774       return _error->Errno("select",_("Select failed"));
 775    }
 776
 777    if (Res == 0)
 778    {
 779       _error->Error(_("Connection timed out"));
 780       return ServerDie(Srv);
 781    }
 782
 783    // Handle server IO
 784    if (Srv->ServerFd != -1 && FD_ISSET(Srv->ServerFd,&rfds))
 785    {
 786       errno = 0;
 787       if (Srv->In.Read(Srv->ServerFd) == false)
 788          return ServerDie(Srv);
 789    }
 790
 791    if (Srv->ServerFd != -1 && FD_ISSET(Srv->ServerFd,&wfds))
 792    {
 793       errno = 0;
 794       if (Srv->Out.Write(Srv->ServerFd) == false)
 795          return ServerDie(Srv);
 796    }
 797
 798    // Send data to the file
 799    if (FileFD != -1 && FD_ISSET(FileFD,&wfds))
 800    {
 801       if (Srv->In.Write(FileFD) == false)
 802          return _error->Errno("write",_("Error writing to output file"));
 803    }
 804
 805    // Handle commands from APT
 806    if (FD_ISSET(STDIN_FILENO,&rfds))
 807    {
 808       if (Run(true) != -1)
 809          exit(100);
 810    }
 811
 812    return true;
 813 }
 814                                                                         /*}}}*/
 815 // HttpMethod::Flush - Dump the buffer into the file                    /*{{{*/
 816 // ---------------------------------------------------------------------
 817 /* This takes the current input buffer from the Server FD and writes it
 818    into the file */
 819 bool HttpMethod::Flush(ServerState *Srv)
 820 {
 821    if (File != 0)
 822    {
 823       // on GNU/kFreeBSD, apt dies on /dev/null because non-blocking
 824       // can't be set
 825       if (File->Name() != "/dev/null")
 826          SetNonBlock(File->Fd(),false);
 827       if (Srv->In.WriteSpace() == false)
 828          return true;
 829
 830       while (Srv->In.WriteSpace() == true)
 831       {
 832          if (Srv->In.Write(File->Fd()) == false)
 833             return _error->Errno("write",_("Error writing to file"));
 834          if (Srv->In.IsLimit() == true)
 835             return true;
 836       }
 837
 838       if (Srv->In.IsLimit() == true || Srv->Encoding == ServerState::Closes)
 839          return true;
 840    }
 841    return false;
 842 }
 843                                                                         /*}}}*/
 844 // HttpMethod::ServerDie - The server has closed the connection.        /*{{{*/
 845 // ---------------------------------------------------------------------
 846 /* */
 847 bool HttpMethod::ServerDie(ServerState *Srv)
 848 {
 849    unsigned int LErrno = errno;
 850
 851    // Dump the buffer to the file
 852    if (Srv->State == ServerState::Data)
 853    {
 854       // on GNU/kFreeBSD, apt dies on /dev/null because non-blocking
 855       // can't be set
 856       if (File->Name() != "/dev/null")
 857          SetNonBlock(File->Fd(),false);
 858       while (Srv->In.WriteSpace() == true)
 859       {
 860          if (Srv->In.Write(File->Fd()) == false)
 861             return _error->Errno("write",_("Error writing to the file"));
 862
 863          // Done
 864          if (Srv->In.IsLimit() == true)
 865             return true;
 866       }
 867    }
 868
 869    // See if this is because the server finished the data stream
 870    if (Srv->In.IsLimit() == false && Srv->State != ServerState::Header &&
 871        Srv->Encoding != ServerState::Closes)
 872    {
 873       Srv->Close();
 874       if (LErrno == 0)
 875          return _error->Error(_("Error reading from server. Remote end closed connection"));
 876       errno = LErrno;
 877       return _error->Errno("read",_("Error reading from server"));
 878    }
 879    else
 880    {
 881       Srv->In.Limit(-1);
 882
 883       // Nothing left in the buffer
 884       if (Srv->In.WriteSpace() == false)
 885          return false;
 886
 887       // We may have got multiple responses back in one packet..
 888       Srv->Close();
 889       return true;
 890    }
 891
 892    return false;
 893 }
 894                                                                         /*}}}*/
 895 // HttpMethod::DealWithHeaders - Handle the retrieved header data       /*{{{*/
 896 // ---------------------------------------------------------------------
 897 /* We look at the header data we got back from the server and decide what
 898    to do. Returns
 899      0 - File is open,
 900      1 - IMS hit
 901      3 - Unrecoverable error
 902      4 - Error with error content page
 903      5 - Unrecoverable non-server error (close the connection) */
 904 int HttpMethod::DealWithHeaders(FetchResult &Res,ServerState *Srv)
 905 {
 906    // Not Modified
 907    if (Srv->Result == 304)
 908    {
 909       unlink(Queue->DestFile.c_str());
 910       Res.IMSHit = true;
 911       Res.LastModified = Queue->LastModified;
 912       return 1;
 913    }
 914
 915    /* We have a reply we dont handle. This should indicate a perm server
 916       failure */
 917    if (Srv->Result < 200 || Srv->Result >= 300)
 918    {
 919       _error->Error("%u %s",Srv->Result,Srv->Code);
 920       if (Srv->HaveContent == true)
 921          return 4;
 922       return 3;
 923    }
 924
 925    // This is some sort of 2xx 'data follows' reply
 926    Res.LastModified = Srv->Date;
 927    Res.Size = Srv->Size;
 928
 929    // Open the file
 930    delete File;
 931    File = new FileFd(Queue->DestFile,FileFd::WriteAny);
 932    if (_error->PendingError() == true)
 933       return 5;
 934
 935    FailFile = Queue->DestFile;
 936    FailFile.c_str();   // Make sure we dont do a malloc in the signal handler
 937    FailFd = File->Fd();
 938    FailTime = Srv->Date;
 939
 940    // Set the expected size
 941    if (Srv->StartPos >= 0)
 942    {
 943       Res.ResumePoint = Srv->StartPos;
 944       ftruncate(File->Fd(),Srv->StartPos);
 945    }
 946
 947    // Set the start point
 948    lseek(File->Fd(),0,SEEK_END);
 949
 950    delete Srv->In.Hash;
 951    Srv->In.Hash = new Hashes;
 952
 953    // Fill the Hash if the file is non-empty (resume)
 954    if (Srv->StartPos > 0)
 955    {
 956       lseek(File->Fd(),0,SEEK_SET);
 957       if (Srv->In.Hash->AddFD(File->Fd(),Srv->StartPos) == false)
 958       {
 959          _error->Errno("read",_("Problem hashing file"));
 960          return 5;
 961       }
 962       lseek(File->Fd(),0,SEEK_END);
 963    }
 964
 965    SetNonBlock(File->Fd(),true);
 966    return 0;
 967 }
 968                                                                         /*}}}*/
 969 // HttpMethod::SigTerm - Handle a fatal signal                          /*{{{*/
 970 // ---------------------------------------------------------------------
 971 /* This closes and timestamps the open file. This is neccessary to get
 972    resume behavoir on user abort */
 973 void HttpMethod::SigTerm(int)
 974 {
 975    if (FailFd == -1)
 976       _exit(100);
 977    close(FailFd);
 978
 979    // Timestamp
 980    struct utimbuf UBuf;
 981    UBuf.actime = FailTime;
 982    UBuf.modtime = FailTime;
 983    utime(FailFile.c_str(),&UBuf);
 984
 985    _exit(100);
 986 }
 987                                                                         /*}}}*/
 988 // HttpMethod::Fetch - Fetch an item                                    /*{{{*/
 989 // ---------------------------------------------------------------------
 990 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 991    depth. */
 992 bool HttpMethod::Fetch(FetchItem *)
 993 {
 994    if (Server == 0)
 995       return true;
 996
 997    // Queue the requests
 998    int Depth = -1;
 999    bool Tail = false;
1000    for (FetchItem *I = Queue; I != 0 && Depth < (signed)PipelineDepth;
1001         I = I->Next, Depth++)
1002    {
1003       // If pipelining is disabled, we only queue 1 request
1004       if (Server->Pipeline == false && Depth >= 0)
1005          break;
1006
1007       // Make sure we stick with the same server
1008       if (Server->Comp(I->Uri) == false)
1009          break;
1010       if (QueueBack == I)
1011          Tail = true;
1012       if (Tail == true)
1013       {
1014          QueueBack = I->Next;
1015          SendReq(I,Server->Out);
1016          continue;
1017       }
1018    }
1019
1020    return true;
1021 };
1022                                                                         /*}}}*/
1023 // HttpMethod::Configuration - Handle a configuration message           /*{{{*/
1024 // ---------------------------------------------------------------------
1025 /* We stash the desired pipeline depth */
1026 bool HttpMethod::Configuration(string Message)
1027 {
1028    if (pkgAcqMethod::Configuration(Message) == false)
1029       return false;
1030
1031    TimeOut = _config->FindI("Acquire::http::Timeout",TimeOut);
1032    PipelineDepth = _config->FindI("Acquire::http::Pipeline-Depth",
1033                                   PipelineDepth);
1034    Debug = _config->FindB("Debug::Acquire::http",false);
1035
1036    return true;
1037 }
1038                                                                         /*}}}*/
1039 // HttpMethod::Loop - Main loop                                         /*{{{*/
1040 // ---------------------------------------------------------------------
1041 /* */
1042 int HttpMethod::Loop()
1043 {
1044    signal(SIGTERM,SigTerm);
1045    signal(SIGINT,SigTerm);
1046
1047    Server = 0;
1048
1049    int FailCounter = 0;
1050    while (1)
1051    {
1052       // We have no commands, wait for some to arrive
1053       if (Queue == 0)
1054       {
1055          if (WaitFd(STDIN_FILENO) == false)
1056             return 0;
1057       }
1058
1059       /* Run messages, we can accept 0 (no message) if we didn't
1060          do a WaitFd above.. Otherwise the FD is closed. */
1061       int Result = Run(true);
1062       if (Result != -1 && (Result != 0 || Queue == 0))
1063          return 100;
1064
1065       if (Queue == 0)
1066          continue;
1067
1068       // Connect to the server
1069       if (Server == 0 || Server->Comp(Queue->Uri) == false)
1070       {
1071          delete Server;
1072          Server = new ServerState(Queue->Uri,this);
1073       }
1074
1075       /* If the server has explicitly said this is the last connection
1076          then we pre-emptively shut down the pipeline and tear down
1077          the connection. This will speed up HTTP/1.0 servers a tad
1078          since we don't have to wait for the close sequence to
1079          complete */
1080       if (Server->Persistent == false)
1081          Server->Close();
1082
1083       // Reset the pipeline
1084       if (Server->ServerFd == -1)
1085          QueueBack = Queue;
1086
1087       // Connnect to the host
1088       if (Server->Open() == false)
1089       {
1090          Fail(true);
1091          delete Server;
1092          Server = 0;
1093          continue;
1094       }
1095
1096       // Fill the pipeline.
1097       Fetch(0);
1098
1099       // Fetch the next URL header data from the server.
1100       switch (Server->RunHeaders())
1101       {
1102          case 0:
1103          break;
1104
1105          // The header data is bad
1106          case 2:
1107          {
1108             _error->Error(_("Bad header data"));
1109             Fail(true);
1110             RotateDNS();
1111             continue;
1112          }
1113
1114          // The server closed a connection during the header get..
1115          default:
1116          case 1:
1117          {
1118             FailCounter++;
1119             _error->Discard();
1120             Server->Close();
1121             Server->Pipeline = false;
1122
1123             if (FailCounter >= 2)
1124             {
1125                Fail(_("Connection failed"),true);
1126                FailCounter = 0;
1127             }
1128
1129             RotateDNS();
1130             continue;
1131          }
1132       };
1133
1134       // Decide what to do.
1135       FetchResult Res;
1136       Res.Filename = Queue->DestFile;
1137       switch (DealWithHeaders(Res,Server))
1138       {
1139          // Ok, the file is Open
1140          case 0:
1141          {
1142             URIStart(Res);
1143
1144             // Run the data
1145             bool Result =  Server->RunData();
1146
1147             /* If the server is sending back sizeless responses then fill in
1148                the size now */
1149             if (Res.Size == 0)
1150                Res.Size = File->Size();
1151
1152             // Close the file, destroy the FD object and timestamp it
1153             FailFd = -1;
1154             delete File;
1155             File = 0;
1156
1157             // Timestamp
1158             struct utimbuf UBuf;
1159             time(&UBuf.actime);
1160             UBuf.actime = Server->Date;
1161             UBuf.modtime = Server->Date;
1162             utime(Queue->DestFile.c_str(),&UBuf);
1163
1164             // Send status to APT
1165             if (Result == true)
1166             {
1167                Res.TakeHashes(*Server->In.Hash);
1168                URIDone(Res);
1169             }
1170             else
1171                Fail(true);
1172
1173             break;
1174          }
1175
1176          // IMS hit
1177          case 1:
1178          {
1179             URIDone(Res);
1180             break;
1181          }
1182
1183          // Hard server error, not found or something
1184          case 3:
1185          {
1186             Fail();
1187             break;
1188          }
1189
1190          // Hard internal error, kill the connection and fail
1191          case 5:
1192          {
1193             delete File;
1194             File = 0;
1195
1196             Fail();
1197             RotateDNS();
1198             Server->Close();
1199             break;
1200          }
1201
1202          // We need to flush the data, the header is like a 404 w/ error text
1203          case 4:
1204          {
1205             Fail();
1206
1207             // Send to content to dev/null
1208             File = new FileFd("/dev/null",FileFd::WriteExists);
1209             Server->RunData();
1210             delete File;
1211             File = 0;
1212             break;
1213          }
1214
1215          default:
1216          Fail(_("Internal error"));
1217          break;
1218       }
1219
1220       FailCounter = 0;
1221    }
1222
1223    return 0;
1224 }
1225                                                                         /*}}}*/
1226
1227 int main()
1228 {
1229    setlocale(LC_ALL, "");
1230
1231    HttpMethod Mth;
1232
1233    return Mth.Loop();
1234 }
1235
1236