X-Git-Url: https://git.saurik.com/apt.git/blobdiff_plain/20801f613690b330c79b4f7a30dc3ff52b722468..6cfadda161ce19e6c8076d0aa118f8f436805a6a:/apt-pkg/acquire-worker.cc

diff --git a/apt-pkg/acquire-worker.cc b/apt-pkg/acquire-worker.cc
index f4d1ad412..dc03a8870 100644
--- a/apt-pkg/acquire-worker.cc
+++ b/apt-pkg/acquire-worker.cc
@@ -43,25 +43,11 @@
 
 using namespace std;
 
-static void ChangeOwnerAndPermissionOfFile(char const * const requester, char const * const file, char const * const user, char const * const group, mode_t const mode) /*{{{*/
-{
-   if (getuid() == 0 && strlen(user) != 0 && strlen(group) != 0) // if we aren't root, we can't chown, so don't try it
-   {
-      // ensure the file is owned by root and has good permissions
-      struct passwd const * const pw = getpwnam(user);
-      struct group const * const gr = getgrnam(group);
-      if (pw != NULL && gr != NULL && chown(file, pw->pw_uid, gr->gr_gid) != 0)
-	 _error->WarningE(requester, "chown to %s:%s of file %s failed", user, group, file);
-   }
-   if (chmod(file, mode) != 0)
-      _error->WarningE(requester, "chmod 0%o of file %s failed", mode, file);
-}
-									/*}}}*/
 // Worker::Worker - Constructor for Queue startup			/*{{{*/
 // ---------------------------------------------------------------------
 /* */
 pkgAcquire::Worker::Worker(Queue *Q,MethodConfig *Cnf,
-			   pkgAcquireStatus *Log) : Log(Log)
+			   pkgAcquireStatus *log) : d(NULL), Log(log)
 {
    OwnerQ = Q;
    Config = Cnf;
@@ -69,23 +55,18 @@ pkgAcquire::Worker::Worker(Queue *Q,MethodConfig *Cnf,
    CurrentItem = 0;
    TotalSize = 0;
    CurrentSize = 0;
-   
-   Construct();   
+
+   Construct();
 }
 									/*}}}*/
 // Worker::Worker - Constructor for method config startup		/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-pkgAcquire::Worker::Worker(MethodConfig *Cnf)
+pkgAcquire::Worker::Worker(MethodConfig *Cnf) : d(NULL), OwnerQ(NULL), Config(Cnf),
+						Access(Cnf->Access), CurrentItem(NULL),
+						CurrentSize(0), TotalSize(0)
 {
-   OwnerQ = 0;
-   Config = Cnf;
-   Access = Cnf->Access;
-   CurrentItem = 0;
-   TotalSize = 0;
-   CurrentSize = 0;
-   
-   Construct();   
+   Construct();
 }
 									/*}}}*/
 // Worker::Construct - Constructor helper				/*{{{*/
@@ -150,7 +131,7 @@ bool pkgAcquire::Worker::Start()
    }
    for (int I = 0; I != 4; I++)
       SetCloseExec(Pipes[I],true);
-   
+
    // Fork off the process
    Process = ExecFork();
    if (Process == 0)
@@ -159,9 +140,9 @@ bool pkgAcquire::Worker::Start()
       dup2(Pipes[1],STDOUT_FILENO);
       dup2(Pipes[2],STDIN_FILENO);
       SetCloseExec(STDOUT_FILENO,false);
-      SetCloseExec(STDIN_FILENO,false);      
+      SetCloseExec(STDIN_FILENO,false);
       SetCloseExec(STDERR_FILENO,false);
-      
+
       const char *Args[2];
       Args[0] = Method.c_str();
       Args[1] = 0;
@@ -179,7 +160,7 @@ bool pkgAcquire::Worker::Start()
    close(Pipes[2]);
    OutReady = false;
    InReady = true;
-   
+
    // Read the configuration data
    if (WaitFd(InFd) == false ||
        ReadMessages() == false)
@@ -188,7 +169,7 @@ bool pkgAcquire::Worker::Start()
    RunMessages();
    if (OwnerQ != 0)
       SendConfiguration();
-   
+
    return true;
 }
 									/*}}}*/
@@ -215,7 +196,7 @@ bool pkgAcquire::Worker::RunMessages()
 
       if (Debug == true)
 	 clog << " <- " << Access << ':' << QuoteString(Message,"\n") << endl;
-      
+
       // Fetch the message number
       char *End;
       int Number = strtol(Message.c_str(),&End,10);
@@ -223,21 +204,24 @@ bool pkgAcquire::Worker::RunMessages()
 	 return _error->Error("Invalid message from method %s: %s",Access.c_str(),Message.c_str());
 
       string URI = LookupTag(Message,"URI");
-      pkgAcquire::Queue::QItem *Itm = 0;
+      pkgAcquire::Queue::QItem *Itm = NULL;
       if (URI.empty() == false)
 	 Itm = OwnerQ->FindItem(URI,this);
 
-      // update used mirror
-      string UsedMirror = LookupTag(Message,"UsedMirror", "");
-      if (!UsedMirror.empty() && 
-          Itm && 
-          Itm->Description.find(" ") != string::npos) 
+      if (Itm != NULL)
       {
-         Itm->Description.replace(0, Itm->Description.find(" "), UsedMirror);
-         // FIXME: will we need this as well?
-         //Itm->ShortDesc = UsedMirror;
+	 // update used mirror
+	 string UsedMirror = LookupTag(Message,"UsedMirror", "");
+	 if (UsedMirror.empty() == false)
+	 {
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+	       (*O)->UsedMirror = UsedMirror;
+
+	    if (Itm->Description.find(" ") != string::npos)
+	       Itm->Description.replace(0, Itm->Description.find(" "), UsedMirror);
+	 }
       }
-      
+
       // Determine the message number and dispatch
       switch (Number)
       {
@@ -246,18 +230,18 @@ bool pkgAcquire::Worker::RunMessages()
 	 if (Capabilities(Message) == false)
 	    return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
 	 break;
-	 
+
 	 // 101 Log
 	 case 101:
 	 if (Debug == true)
 	    clog << " <- (log) " << LookupTag(Message,"Message") << endl;
 	 break;
-	 
+
 	 // 102 Status
 	 case 102:
 	 Status = LookupTag(Message,"Message");
 	 break;
-	    
+
          // 103 Redirect
          case 103:
          {
@@ -266,27 +250,49 @@ bool pkgAcquire::Worker::RunMessages()
                _error->Error("Method gave invalid 103 Redirect message");
                break;
             }
- 
-            string NewURI = LookupTag(Message,"New-URI",URI.c_str());
+
+	    std::string const NewURI = LookupTag(Message,"New-URI",URI.c_str());
             Itm->URI = NewURI;
 
 	    ItemDone();
 
-	    pkgAcquire::Item *Owner = Itm->Owner;
-	    pkgAcquire::ItemDesc Desc = *Itm;
-
 	    // Change the status so that it can be dequeued
-	    Owner->Status = pkgAcquire::Item::StatIdle;
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+	       (*O)->Status = pkgAcquire::Item::StatIdle;
 	    // Mark the item as done (taking care of all queues)
 	    // and then put it in the main queue again
+	    std::vector<Item*> const ItmOwners = Itm->Owners;
 	    OwnerQ->ItemDone(Itm);
-	    OwnerQ->Owner->Enqueue(Desc);
-
-	    if (Log != 0)
-	       Log->Done(Desc);
+	    Itm = NULL;
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = ItmOwners.begin(); O != ItmOwners.end(); ++O)
+	    {
+	       pkgAcquire::Item *Owner = *O;
+	       pkgAcquire::ItemDesc &desc = Owner->GetItemDesc();
+	       // if we change site, treat it as a mirror change
+	       if (URI::SiteOnly(NewURI) != URI::SiteOnly(desc.URI))
+	       {
+		  std::string const OldSite = desc.Description.substr(0, desc.Description.find(" "));
+		  if (likely(APT::String::Startswith(desc.URI, OldSite)))
+		  {
+		     std::string const OldExtra = desc.URI.substr(OldSite.length() + 1);
+		     if (likely(APT::String::Endswith(NewURI, OldExtra)))
+		     {
+			std::string const NewSite = NewURI.substr(0, NewURI.length() - OldExtra.length());
+			Owner->UsedMirror = URI::ArchiveOnly(NewSite);
+			if (desc.Description.find(" ") != string::npos)
+			   desc.Description.replace(0, desc.Description.find(" "), Owner->UsedMirror);
+		     }
+		  }
+	       }
+	       desc.URI = NewURI;
+	       OwnerQ->Owner->Enqueue(desc);
+
+	       if (Log != 0)
+		  Log->Done(desc);
+	    }
             break;
          }
-   
+
 	 // 200 URI Start
 	 case 200:
 	 {
@@ -295,23 +301,27 @@ bool pkgAcquire::Worker::RunMessages()
 	       _error->Error("Method gave invalid 200 URI Start message");
 	       break;
 	    }
-	    
+
 	    CurrentItem = Itm;
 	    CurrentSize = 0;
 	    TotalSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
 	    ResumePoint = strtoull(LookupTag(Message,"Resume-Point","0").c_str(), NULL, 10);
-	    Itm->Owner->Start(Message,strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10));
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+	    {
+	       (*O)->Start(Message, TotalSize);
 
-	    // Display update before completion
-	    if (Log != 0 && Log->MorePulses == true)
-	       Log->Pulse(Itm->Owner->GetOwner());
-	    
-	    if (Log != 0)
-	       Log->Fetch(*Itm);
+	       // Display update before completion
+	       if (Log != 0)
+	       {
+		  if (Log->MorePulses == true)
+		     Log->Pulse((*O)->GetOwner());
+		  Log->Fetch((*O)->GetItemDesc());
+	       }
+	    }
 
 	    break;
 	 }
-	 
+
 	 // 201 URI Done
 	 case 201:
 	 {
@@ -320,72 +330,113 @@ bool pkgAcquire::Worker::RunMessages()
 	       _error->Error("Method gave invalid 201 URI Done message");
 	       break;
 	    }
-	    
-	    pkgAcquire::Item *Owner = Itm->Owner;
-	    pkgAcquire::ItemDesc Desc = *Itm;
 
-	    if (RealFileExists(Owner->DestFile))
-	       ChangeOwnerAndPermissionOfFile("201::URIDone", Owner->DestFile.c_str(), "root", "root", 0644);
+	    PrepareFiles("201::URIDone", Itm);
 
 	    // Display update before completion
 	    if (Log != 0 && Log->MorePulses == true)
-	       Log->Pulse(Owner->GetOwner());
-	    
-	    OwnerQ->ItemDone(Itm);
-	    unsigned long long const ServerSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
-            bool isHit = StringToBool(LookupTag(Message,"IMS-Hit"),false) ||
-                         StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false);
-            // Using the https method the server might return 200, but the
-            // If-Modified-Since condition is not satsified, libcurl will
-            // discard the download. In this case, however, TotalSize will be
-            // set to the actual size of the file, while ServerSize will be set
-            // to 0. Therefore, if the item is marked as a hit and the
-            // downloaded size (ServerSize) is 0, we ignore TotalSize.
-	    if (TotalSize != 0 && (!isHit || ServerSize != 0) && ServerSize != TotalSize)
-	       _error->Warning("Size of file %s is not what the server reported %s %llu",
-			       Owner->DestFile.c_str(), LookupTag(Message,"Size","0").c_str(),TotalSize);
-
-	    // see if there is a hash to verify
+	       for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+		  Log->Pulse((*O)->GetOwner());
+
+	    std::string const filename = LookupTag(Message, "Filename", Itm->Owner->DestFile.c_str());
 	    HashStringList ReceivedHashes;
-	    HashStringList expectedHashes = Owner->HashSums();
-	    for (HashStringList::const_iterator hs = expectedHashes.begin(); hs != expectedHashes.end(); ++hs)
 	    {
-	       std::string const tagname = hs->HashType() + "-Hash";
-	       std::string const hashsum = LookupTag(Message, tagname.c_str());
-	       if (hashsum.empty() == false)
-		  ReceivedHashes.push_back(HashString(hs->HashType(), hashsum));
+	       // see if we got hashes to verify
+	       for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
+	       {
+		  std::string const tagname = std::string(*type) + "-Hash";
+		  std::string const hashsum = LookupTag(Message, tagname.c_str());
+		  if (hashsum.empty() == false)
+		     ReceivedHashes.push_back(HashString(*type, hashsum));
+	       }
+	       // not all methods always sent Hashes our way
+	       if (ReceivedHashes.usable() == false)
+	       {
+		  HashStringList const ExpectedHashes = Itm->GetExpectedHashes();
+		  if (ExpectedHashes.usable() == true && RealFileExists(filename))
+		  {
+		     Hashes calc(ExpectedHashes);
+		     FileFd file(filename, FileFd::ReadOnly, FileFd::None);
+		     calc.AddFD(file);
+		     ReceivedHashes = calc.GetHashStringList();
+		  }
+	       }
 	    }
 
-	    if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
-	    {
-	       std::clog << "201 URI Done: " << Owner->DescURI() << endl
-		  << "ReceivedHash:" << endl;
-	       for (HashStringList::const_iterator hs = ReceivedHashes.begin(); hs != ReceivedHashes.end(); ++hs)
-		  std::clog <<  "\t- " << hs->toStr() << std::endl;
-	       std::clog << "ExpectedHash:" << endl;
-	       for (HashStringList::const_iterator hs = expectedHashes.begin(); hs != expectedHashes.end(); ++hs)
-		  std::clog <<  "\t- " << hs->toStr() << std::endl;
-	       std::clog << endl;
-	    }
-	    Owner->Done(Message, ServerSize, ReceivedHashes, Config);
-	    ItemDone();
+	    // only local files can refer other filenames and counting them as fetched would be unfair
+	    if (Log !=  NULL && filename != Itm->Owner->DestFile)
+	       Log->Fetched(ReceivedHashes.FileSize(),atoi(LookupTag(Message,"Resume-Point","0").c_str()));
+
+	    std::vector<Item*> const ItmOwners = Itm->Owners;
+	    OwnerQ->ItemDone(Itm);
+	    Itm = NULL;
 
-	    // Log that we are done
-	    if (Log != 0)
+	    bool const isIMSHit = StringToBool(LookupTag(Message,"IMS-Hit"),false) ||
+	       StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false);
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = ItmOwners.begin(); O != ItmOwners.end(); ++O)
 	    {
-	       if (isHit)
+	       pkgAcquire::Item * const Owner = *O;
+	       HashStringList const ExpectedHashes = Owner->GetExpectedHashes();
+	       if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
 	       {
-		  /* Hide 'hits' for local only sources - we also manage to
-		     hide gets */
-		  if (Config->LocalOnly == false)
-		     Log->IMSHit(Desc);
-	       }	       
+		  std::clog << "201 URI Done: " << Owner->DescURI() << endl
+		     << "ReceivedHash:" << endl;
+		  for (HashStringList::const_iterator hs = ReceivedHashes.begin(); hs != ReceivedHashes.end(); ++hs)
+		     std::clog <<  "\t- " << hs->toStr() << std::endl;
+		  std::clog << "ExpectedHash:" << endl;
+		  for (HashStringList::const_iterator hs = ExpectedHashes.begin(); hs != ExpectedHashes.end(); ++hs)
+		     std::clog <<  "\t- " << hs->toStr() << std::endl;
+		  std::clog << endl;
+	       }
+
+	       // decide if what we got is what we expected
+	       bool consideredOkay = false;
+	       if (ExpectedHashes.usable())
+	       {
+		  if (ReceivedHashes.usable() == false)
+		  {
+		     /* IMS-Hits can't be checked here as we will have uncompressed file,
+			but the hashes for the compressed file. What we have was good through
+			so all we have to ensure later is that we are not stalled. */
+		     consideredOkay = isIMSHit;
+		  }
+		  else if (ReceivedHashes == ExpectedHashes)
+		     consideredOkay = true;
+		  else
+		     consideredOkay = false;
+
+	       }
+	       else if (Owner->HashesRequired() == true)
+		  consideredOkay = false;
+	       else
+		  consideredOkay = true;
+
+	       if (consideredOkay == true)
+	       {
+		  Owner->Done(Message, ReceivedHashes, Config);
+
+		  // Log that we are done
+		  if (Log != 0)
+		  {
+		     if (isIMSHit)
+			Log->IMSHit(Owner->GetItemDesc());
+		     else
+			Log->Done(Owner->GetItemDesc());
+		  }
+	       }
 	       else
-		  Log->Done(Desc);
+	       {
+		  Owner->Status = pkgAcquire::Item::StatAuthError;
+		  Owner->Failed(Message,Config);
+
+		  if (Log != 0)
+		     Log->Fail(Owner->GetItemDesc());
+	       }
 	    }
+	    ItemDone();
 	    break;
-	 }	 
-	 
+	 }
+
 	 // 400 URI Failure
 	 case 400:
 	 {
@@ -396,44 +447,46 @@ bool pkgAcquire::Worker::RunMessages()
 	       break;
 	    }
 
+	    PrepareFiles("400::URIFailure", Itm);
+
 	    // Display update before completion
 	    if (Log != 0 && Log->MorePulses == true)
-	       Log->Pulse(Itm->Owner->GetOwner());
-
-	    pkgAcquire::Item *Owner = Itm->Owner;
-	    pkgAcquire::ItemDesc Desc = *Itm;
-
-	    if (RealFileExists(Owner->DestFile))
-	       ChangeOwnerAndPermissionOfFile("400::URIFailure", Owner->DestFile.c_str(), "root", "root", 0644);
+	       for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+		  Log->Pulse((*O)->GetOwner());
 
+	    std::vector<Item*> const ItmOwners = Itm->Owners;
 	    OwnerQ->ItemDone(Itm);
+	    Itm = NULL;
+
+	    for (pkgAcquire::Queue::QItem::owner_iterator O = ItmOwners.begin(); O != ItmOwners.end(); ++O)
+	    {
+	       // set some status
+	       if(LookupTag(Message,"FailReason") == "Timeout" ||
+		     LookupTag(Message,"FailReason") == "TmpResolveFailure" ||
+		     LookupTag(Message,"FailReason") == "ResolveFailure" ||
+		     LookupTag(Message,"FailReason") == "ConnectionRefused")
+		  (*O)->Status = pkgAcquire::Item::StatTransientNetworkError;
 
-	    // set some status
-	    if(LookupTag(Message,"FailReason") == "Timeout" || 
-	       LookupTag(Message,"FailReason") == "TmpResolveFailure" ||
-	       LookupTag(Message,"FailReason") == "ResolveFailure" ||
-	       LookupTag(Message,"FailReason") == "ConnectionRefused") 
-	       Owner->Status = pkgAcquire::Item::StatTransientNetworkError;
+	       (*O)->Failed(Message,Config);
 
-	    Owner->Failed(Message,Config);
+	       if (Log != 0)
+		  Log->Fail((*O)->GetItemDesc());
+	    }
 	    ItemDone();
 
-	    if (Log != 0)
-	       Log->Fail(Desc);
-
 	    break;
-	 }	 
-	 
+	 }
+
 	 // 401 General Failure
 	 case 401:
 	 _error->Error("Method %s General failure: %s",Access.c_str(),LookupTag(Message,"Message").c_str());
 	 break;
-	 
+
 	 // 403 Media Change
 	 case 403:
-	 MediaChange(Message); 
+	 MediaChange(Message);
 	 break;
-      }      
+      }
    }
    return true;
 }
@@ -446,7 +499,7 @@ bool pkgAcquire::Worker::Capabilities(string Message)
 {
    if (Config == 0)
       return true;
-   
+
    Config->Version = LookupTag(Message,"Version");
    Config->SingleInstance = StringToBool(LookupTag(Message,"Single-Instance"),false);
    Config->Pipeline = StringToBool(LookupTag(Message,"Pipeline"),false);
@@ -461,13 +514,13 @@ bool pkgAcquire::Worker::Capabilities(string Message)
       clog << "Configured access method " << Config->Access << endl;
       clog << "Version:" << Config->Version <<
 	      " SingleInstance:" << Config->SingleInstance <<
-	      " Pipeline:" << Config->Pipeline << 
-	      " SendConfig:" << Config->SendConfig << 
-	      " LocalOnly: " << Config->LocalOnly << 
-	      " NeedsCleanup: " << Config->NeedsCleanup << 
+	      " Pipeline:" << Config->Pipeline <<
+	      " SendConfig:" << Config->SendConfig <<
+	      " LocalOnly: " << Config->LocalOnly <<
+	      " NeedsCleanup: " << Config->NeedsCleanup <<
 	      " Removable: " << Config->Removable << endl;
    }
-   
+
    return true;
 }
 									/*}}}*/
@@ -477,10 +530,10 @@ bool pkgAcquire::Worker::Capabilities(string Message)
 bool pkgAcquire::Worker::MediaChange(string Message)
 {
    int status_fd = _config->FindI("APT::Status-Fd",-1);
-   if(status_fd > 0) 
+   if(status_fd > 0)
    {
       string Media = LookupTag(Message,"Media");
-      string Drive = LookupTag(Message,"Drive"); 
+      string Drive = LookupTag(Message,"Drive");
       ostringstream msg,status;
       ioprintf(msg,_("Please insert the disc labeled: "
 		     "'%s' "
@@ -550,21 +603,29 @@ bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
 {
    if (OutFd == -1)
       return false;
-   
+
    string Message = "600 URI Acquire\n";
    Message.reserve(300);
    Message += "URI: " + Item->URI;
    Message += "\nFilename: " + Item->Owner->DestFile;
-   HashStringList const hsl = Item->Owner->HashSums();
+
+   HashStringList const hsl = Item->GetExpectedHashes();
    for (HashStringList::const_iterator hs = hsl.begin(); hs != hsl.end(); ++hs)
       Message += "\nExpected-" + hs->HashType() + ": " + hs->HashValue();
-   if(Item->Owner->FileSize > 0)
+
+   if (hsl.FileSize() == 0)
    {
-      string MaximumSize;
-      strprintf(MaximumSize, "%llu", Item->Owner->FileSize);
-      Message += "\nMaximum-Size: " + MaximumSize;
+      unsigned long long FileSize = Item->GetMaximumSize();
+      if(FileSize > 0)
+      {
+	 string MaximumSize;
+	 strprintf(MaximumSize, "%llu", FileSize);
+	 Message += "\nMaximum-Size: " + MaximumSize;
+      }
    }
-   Message += Item->Owner->Custom600Headers();
+
+   Item->SyncDestinationFiles();
+   Message += Item->Custom600Headers();
    Message += "\n\n";
 
    if (RealFileExists(Item->Owner->DestFile))
@@ -578,7 +639,7 @@ bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
       clog << " -> " << Access << ':' << QuoteString(Message,"\n") << endl;
    OutQueue += Message;
    OutReady = true;
-   
+
    return true;
 }
 									/*}}}*/
@@ -600,7 +661,7 @@ bool pkgAcquire::Worker::OutFdReady()
    OutQueue.erase(0,Res);
    if (OutQueue.empty() == true)
       OutReady = false;
-   
+
    return true;
 }
 									/*}}}*/
@@ -622,7 +683,7 @@ bool pkgAcquire::Worker::InFdReady()
 bool pkgAcquire::Worker::MethodFailure()
 {
    _error->Error("Method %s has died unexpectedly!",Access.c_str());
-   
+
    // do not reap the child here to show meaningfull error to the user
    ExecWait(Process,Access.c_str(),false);
    Process = -1;
@@ -634,26 +695,22 @@ bool pkgAcquire::Worker::MethodFailure()
    InReady = false;
    OutQueue = string();
    MessageQueue.erase(MessageQueue.begin(),MessageQueue.end());
-   
+
    return false;
 }
 									/*}}}*/
-// Worker::Pulse - Called periodically 					/*{{{*/
+// Worker::Pulse - Called periodically					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
 void pkgAcquire::Worker::Pulse()
 {
    if (CurrentItem == 0)
       return;
- 
+
    struct stat Buf;
    if (stat(CurrentItem->Owner->DestFile.c_str(),&Buf) != 0)
       return;
    CurrentSize = Buf.st_size;
-   
-   // Hmm? Should not happen...
-   if (CurrentSize > TotalSize && TotalSize != 0)
-      TotalSize = CurrentSize;
 }
 									/*}}}*/
 // Worker::ItemDone - Called when the current item is finished		/*{{{*/
@@ -667,3 +724,33 @@ void pkgAcquire::Worker::ItemDone()
    Status = string();
 }
 									/*}}}*/
+void pkgAcquire::Worker::PrepareFiles(char const * const caller, pkgAcquire::Queue::QItem const * const Itm)/*{{{*/
+{
+   if (RealFileExists(Itm->Owner->DestFile))
+   {
+      ChangeOwnerAndPermissionOfFile(caller, Itm->Owner->DestFile.c_str(), "root", "root", 0644);
+      std::string const filename = Itm->Owner->DestFile;
+      for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+      {
+	 pkgAcquire::Item const * const Owner = *O;
+	 if (Owner->DestFile == filename)
+	    continue;
+	 unlink(Owner->DestFile.c_str());
+	 if (link(filename.c_str(), Owner->DestFile.c_str()) != 0)
+	 {
+	    // different mounts can't happen for us as we download to lists/ by default,
+	    // but if the system is reused by others the locations can potentially be on
+	    // different disks, so use symlink as poor-men replacement.
+	    // FIXME: Real copying as last fallback, but that is costly, so offload to a method preferable
+	    if (symlink(filename.c_str(), Owner->DestFile.c_str()) != 0)
+	       _error->Error("Can't create (sym)link of file %s to %s", filename.c_str(), Owner->DestFile.c_str());
+	 }
+      }
+   }
+   else
+   {
+      for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+	 unlink((*O)->DestFile.c_str());
+   }
+}
+									/*}}}*/