apt-pkg/acquire-worker.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: acquire-worker.cc,v 1.11 1998/11/09 01:09:23 jgg Exp $
   4 /* ######################################################################
   5
   6    Acquire Worker
   7
   8    The worker process can startup either as a Configuration prober
   9    or as a queue runner. As a configuration prober it only reads the
  10    configuration message and
  11
  12    ##################################################################### */
  13                                                                         /*}}}*/
  14 // Include Files                                                        /*{{{*/
  15 #ifdef __GNUG__
  16 #pragma implementation "apt-pkg/acquire-worker.h"
  17 #endif
  18 #include <apt-pkg/acquire-worker.h>
  19 #include <apt-pkg/acquire-item.h>
  20 #include <apt-pkg/configuration.h>
  21 #include <apt-pkg/error.h>
  22 #include <apt-pkg/fileutl.h>
  23 #include <strutl.h>
  24
  25 #include <sys/stat.h>
  26 #include <unistd.h>
  27 #include <signal.h>
  28 #include <wait.h>
  29                                                                         /*}}}*/
  30
  31 // Worker::Worker - Constructor for Queue startup                       /*{{{*/
  32 // ---------------------------------------------------------------------
  33 /* */
  34 pkgAcquire::Worker::Worker(Queue *Q,MethodConfig *Cnf,
  35                            pkgAcquireStatus *Log) : Log(Log)
  36 {
  37    OwnerQ = Q;
  38    Config = Cnf;
  39    Access = Cnf->Access;
  40    CurrentItem = 0;
  41
  42    Construct();
  43 }
  44                                                                         /*}}}*/
  45 // Worker::Worker - Constructor for method config startup               /*{{{*/
  46 // ---------------------------------------------------------------------
  47 /* */
  48 pkgAcquire::Worker::Worker(MethodConfig *Cnf)
  49 {
  50    OwnerQ = 0;
  51    Config = Cnf;
  52    Access = Cnf->Access;
  53    CurrentItem = 0;
  54
  55    Construct();
  56 }
  57                                                                         /*}}}*/
  58 // Worker::Construct - Constructor helper                               /*{{{*/
  59 // ---------------------------------------------------------------------
  60 /* */
  61 void pkgAcquire::Worker::Construct()
  62 {
  63    NextQueue = 0;
  64    NextAcquire = 0;
  65    Process = -1;
  66    InFd = -1;
  67    OutFd = -1;
  68    OutReady = false;
  69    InReady = false;
  70    Debug = _config->FindB("Debug::pkgAcquire::Worker",false);
  71 }
  72                                                                         /*}}}*/
  73 // Worker::~Worker - Destructor                                         /*{{{*/
  74 // ---------------------------------------------------------------------
  75 /* */
  76 pkgAcquire::Worker::~Worker()
  77 {
  78    close(InFd);
  79    close(OutFd);
  80
  81    if (Process > 0)
  82    {
  83       kill(Process,SIGINT);
  84       if (waitpid(Process,0,0) != Process)
  85          _error->Warning("I waited but nothing was there!");
  86    }
  87 }
  88                                                                         /*}}}*/
  89 // Worker::Start - Start the worker process                             /*{{{*/
  90 // ---------------------------------------------------------------------
  91 /* This forks the method and inits the communication channel */
  92 bool pkgAcquire::Worker::Start()
  93 {
  94    // Get the method path
  95    string Method = _config->FindDir("Dir::Bin::Methods") + Access;
  96    if (FileExists(Method) == false)
  97       return _error->Error("The method driver %s could not be found.",Method.c_str());
  98
  99    if (Debug == true)
 100       clog << "Starting method '" << Method << '\'' << endl;
 101
 102    // Create the pipes
 103    int Pipes[4] = {-1,-1,-1,-1};
 104    if (pipe(Pipes) != 0 || pipe(Pipes+2) != 0)
 105    {
 106       _error->Errno("pipe","Failed to create IPC pipe to subprocess");
 107       for (int I = 0; I != 4; I++)
 108          close(Pipes[I]);
 109       return false;
 110    }
 111    for (int I = 0; I != 4; I++)
 112       SetCloseExec(Pipes[0],true);
 113
 114    // Fork off the process
 115    Process = fork();
 116    if (Process < 0)
 117    {
 118       cerr << "FATAL -> Failed to fork." << endl;
 119       exit(100);
 120    }
 121
 122    // Spawn the subprocess
 123    if (Process == 0)
 124    {
 125       // Setup the FDs
 126       dup2(Pipes[1],STDOUT_FILENO);
 127       dup2(Pipes[2],STDIN_FILENO);
 128       dup2(((filebuf *)clog.rdbuf())->fd(),STDERR_FILENO);
 129       SetCloseExec(STDOUT_FILENO,false);
 130       SetCloseExec(STDIN_FILENO,false);
 131       SetCloseExec(STDERR_FILENO,false);
 132
 133       const char *Args[2];
 134       Args[0] = Method.c_str();
 135       Args[1] = 0;
 136       execv(Args[0],(char **)Args);
 137       cerr << "Failed to exec method " << Args[0] << endl;
 138       exit(100);
 139    }
 140
 141    // Fix up our FDs
 142    InFd = Pipes[0];
 143    OutFd = Pipes[3];
 144    SetNonBlock(Pipes[0],true);
 145    SetNonBlock(Pipes[3],true);
 146    close(Pipes[1]);
 147    close(Pipes[2]);
 148    OutReady = false;
 149    InReady = true;
 150
 151    // Read the configuration data
 152    if (WaitFd(InFd) == false ||
 153        ReadMessages() == false)
 154       return _error->Error("Method %s did not start correctly",Method.c_str());
 155
 156    RunMessages();
 157    if (OwnerQ != 0)
 158       SendConfiguration();
 159
 160    return true;
 161 }
 162                                                                         /*}}}*/
 163 // Worker::ReadMessages - Read all pending messages into the list       /*{{{*/
 164 // ---------------------------------------------------------------------
 165 /* */
 166 bool pkgAcquire::Worker::ReadMessages()
 167 {
 168    if (::ReadMessages(InFd,MessageQueue) == false)
 169       return MethodFailure();
 170    return true;
 171 }
 172                                                                         /*}}}*/
 173 // Worker::RunMessage - Empty the message queue                         /*{{{*/
 174 // ---------------------------------------------------------------------
 175 /* This takes the messages from the message queue and runs them through
 176    the parsers in order. */
 177 bool pkgAcquire::Worker::RunMessages()
 178 {
 179    while (MessageQueue.empty() == false)
 180    {
 181       string Message = MessageQueue.front();
 182       MessageQueue.erase(MessageQueue.begin());
 183
 184       if (Debug == true)
 185          clog << " <- " << Access << ':' << QuoteString(Message,"\n") << endl;
 186
 187       // Fetch the message number
 188       char *End;
 189       int Number = strtol(Message.c_str(),&End,10);
 190       if (End == Message.c_str())
 191          return _error->Error("Invalid message from method %s: %s",Access.c_str(),Message.c_str());
 192
 193       string URI = LookupTag(Message,"URI");
 194       pkgAcquire::Queue::QItem *Itm = 0;
 195       if (URI.empty() == false)
 196          Itm = OwnerQ->FindItem(URI,this);
 197
 198       // Determine the message number and dispatch
 199       switch (Number)
 200       {
 201          // 100 Capabilities
 202          case 100:
 203          if (Capabilities(Message) == false)
 204             return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
 205          break;
 206
 207          // 101 Log
 208          case 101:
 209          if (Debug == true)
 210             clog << " <- (log) " << LookupTag(Message,"Message") << endl;
 211          break;
 212
 213          // 102 Status
 214          case 102:
 215          Status = LookupTag(Message,"Message");
 216          break;
 217
 218          // 200 URI Start
 219          case 200:
 220          {
 221             if (Itm == 0)
 222             {
 223                _error->Error("Method gave invalid 200 URI Start message");
 224                break;
 225             }
 226
 227             CurrentItem = Itm;
 228             CurrentSize = 0;
 229             TotalSize = atoi(LookupTag(Message,"Size","0").c_str());
 230             Itm->Owner->Start(Message,atoi(LookupTag(Message,"Size","0").c_str()));
 231
 232             if (Log != 0)
 233                Log->Fetch(*Itm);
 234
 235             break;
 236          }
 237
 238          // 201 URI Done
 239          case 201:
 240          {
 241             if (Itm == 0)
 242             {
 243                _error->Error("Method gave invalid 201 URI Done message");
 244                break;
 245             }
 246
 247             pkgAcquire::Item *Owner = Itm->Owner;
 248             pkgAcquire::ItemDesc Desc = *Itm;
 249             OwnerQ->ItemDone(Itm);
 250             Owner->Done(Message,atoi(LookupTag(Message,"Size","0").c_str()),
 251                                           LookupTag(Message,"MD5-Hash"));
 252             ItemDone();
 253
 254             // Log that we are done
 255             if (Log != 0)
 256             {
 257                if (StringToBool(LookupTag(Message,"IMS-Hit"),false) == true ||
 258                    StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false) == true)
 259                   Log->IMSHit(Desc);
 260                else
 261                   Log->Done(Desc);
 262             }
 263             break;
 264          }
 265
 266          // 400 URI Failure
 267          case 400:
 268          {
 269             if (Itm == 0)
 270             {
 271                _error->Error("Method gave invalid 400 URI Failure message");
 272                break;
 273             }
 274
 275             pkgAcquire::Item *Owner = Itm->Owner;
 276             pkgAcquire::ItemDesc Desc = *Itm;
 277             OwnerQ->ItemDone(Itm);
 278             Owner->Failed(Message);
 279             ItemDone();
 280
 281             if (Log != 0)
 282                Log->Fail(Desc);
 283
 284             break;
 285          }
 286
 287          // 401 General Failure
 288          case 401:
 289          _error->Error("Method %s General failure: %s",LookupTag(Message,"Message").c_str());
 290          break;
 291       }
 292    }
 293    return true;
 294 }
 295                                                                         /*}}}*/
 296 // Worker::Capabilities - 100 Capabilities handler                      /*{{{*/
 297 // ---------------------------------------------------------------------
 298 /* This parses the capabilities message and dumps it into the configuration
 299    structure. */
 300 bool pkgAcquire::Worker::Capabilities(string Message)
 301 {
 302    if (Config == 0)
 303       return true;
 304
 305    Config->Version = LookupTag(Message,"Version");
 306    Config->SingleInstance = StringToBool(LookupTag(Message,"Single-Instance"),false);
 307    Config->PreScan = StringToBool(LookupTag(Message,"Pre-Scan"),false);
 308    Config->Pipeline = StringToBool(LookupTag(Message,"Pipeline"),false);
 309    Config->SendConfig = StringToBool(LookupTag(Message,"Send-Config"),false);
 310
 311    // Some debug text
 312    if (Debug == true)
 313    {
 314       clog << "Configured access method " << Config->Access << endl;
 315       clog << "Version:" << Config->Version << " SingleInstance:" <<
 316          Config->SingleInstance << " PreScan: " << Config->PreScan <<
 317          " Pipeline:" << Config->Pipeline << " SendConfig:" <<
 318          Config->SendConfig << endl;
 319    }
 320
 321    return true;
 322 }
 323                                                                         /*}}}*/
 324 // Worker::SendConfiguration - Send the config to the method            /*{{{*/
 325 // ---------------------------------------------------------------------
 326 /* */
 327 bool pkgAcquire::Worker::SendConfiguration()
 328 {
 329    if (Config->SendConfig == false)
 330       return true;
 331
 332    if (OutFd == -1)
 333       return false;
 334
 335    string Message = "601 Configuration\n";
 336    Message.reserve(2000);
 337
 338    /* Write out all of the configuration directives by walking the
 339       configuration tree */
 340    const Configuration::Item *Top = _config->Tree(0);
 341    for (; Top != 0;)
 342    {
 343       if (Top->Value.empty() == false)
 344       {
 345          string Line = "Config-Item: " + Top->FullTag() + "=";
 346          Line += QuoteString(Top->Value,"\n") + '\n';
 347          Message += Line;
 348       }
 349
 350       if (Top->Child != 0)
 351       {
 352          Top = Top->Child;
 353          continue;
 354       }
 355
 356       while (Top != 0 && Top->Next == 0)
 357          Top = Top->Parent;
 358       if (Top != 0)
 359          Top = Top->Next;
 360    }
 361    Message += '\n';
 362
 363    if (Debug == true)
 364       clog << " -> " << Access << ':' << QuoteString(Message,"\n") << endl;
 365    OutQueue += Message;
 366    OutReady = true;
 367
 368    return true;
 369 }
 370                                                                         /*}}}*/
 371 // Worker::QueueItem - Add an item to the outbound queue                /*{{{*/
 372 // ---------------------------------------------------------------------
 373 /* Send a URI Acquire message to the method */
 374 bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
 375 {
 376    if (OutFd == -1)
 377       return false;
 378
 379    string Message = "600 URI Acquire\n";
 380    Message.reserve(300);
 381    Message += "URI: " + Item->URI;
 382    Message += "\nFilename: " + Item->Owner->DestFile;
 383    Message += Item->Owner->Custom600Headers();
 384    Message += "\n\n";
 385
 386    if (Debug == true)
 387       clog << " -> " << Access << ':' << QuoteString(Message,"\n") << endl;
 388    OutQueue += Message;
 389    OutReady = true;
 390
 391    return true;
 392 }
 393                                                                         /*}}}*/
 394 // Worker::OutFdRead - Out bound FD is ready                            /*{{{*/
 395 // ---------------------------------------------------------------------
 396 /* */
 397 bool pkgAcquire::Worker::OutFdReady()
 398 {
 399    int Res = write(OutFd,OutQueue.begin(),OutQueue.length());
 400    if (Res <= 0)
 401       return MethodFailure();
 402
 403    // Hmm.. this should never happen.
 404    if (Res < 0)
 405       return true;
 406
 407    OutQueue.erase(0,Res);
 408    if (OutQueue.empty() == true)
 409       OutReady = false;
 410
 411    return true;
 412 }
 413                                                                         /*}}}*/
 414 // Worker::InFdRead - In bound FD is ready                              /*{{{*/
 415 // ---------------------------------------------------------------------
 416 /* */
 417 bool pkgAcquire::Worker::InFdReady()
 418 {
 419    if (ReadMessages() == false)
 420       return false;
 421    RunMessages();
 422    return true;
 423 }
 424                                                                         /*}}}*/
 425 // Worker::MethodFailure - Called when the method fails                 /*{{{*/
 426 // ---------------------------------------------------------------------
 427 /* This is called when the method is belived to have failed, probably because
 428    read returned -1. */
 429 bool pkgAcquire::Worker::MethodFailure()
 430 {
 431    cerr << "Method " << Access << " has died unexpectedly!" << endl;
 432    if (waitpid(Process,0,0) != Process)
 433       _error->Warning("I waited but nothing was there!");
 434    Process = -1;
 435    close(InFd);
 436    close(OutFd);
 437    InFd = -1;
 438    OutFd = -1;
 439    OutReady = false;
 440    InReady = false;
 441    OutQueue = string();
 442    MessageQueue.erase(MessageQueue.begin(),MessageQueue.end());
 443
 444    return false;
 445 }
 446                                                                         /*}}}*/
 447 // Worker::Pulse - Called periodically                                  /*{{{*/
 448 // ---------------------------------------------------------------------
 449 /* */
 450 void pkgAcquire::Worker::Pulse()
 451 {
 452    if (CurrentItem == 0)
 453       return;
 454
 455
 456    struct stat Buf;
 457    if (stat(CurrentItem->Owner->DestFile.c_str(),&Buf) != 0)
 458       return;
 459    CurrentSize = Buf.st_size;
 460 }
 461                                                                         /*}}}*/
 462 // Worker::ItemDone - Called when the current item is finished          /*{{{*/
 463 // ---------------------------------------------------------------------
 464 /* */
 465 void pkgAcquire::Worker::ItemDone()
 466 {
 467    CurrentItem = 0;
 468    CurrentSize = 0;
 469    TotalSize = 0;
 470    Status = string();
 471 }
 472                                                                         /*}}}*/