close server if parsing of header field failed

[apt.git] / apt-pkg / acquire-worker.cc

diff --git a/apt-pkg/acquire-worker.cc b/apt-pkg/acquire-worker.cc
index ef195d44bfb23541a27dfdd224e64691941e1f87..9ed7b5b28fb0d5cc3d42b09cdf14089134f5a63a 100644 (file)
--- a/apt-pkg/acquire-worker.cc
+++ b/apt-pkg/acquire-worker.cc
@@ -23,10 +23,10 @@
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/hashes.h>
 
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/hashes.h>
 

+#include <algorithm>

 #include <string>
 #include <vector>
 #include <iostream>
 #include <string>
 #include <vector>
 #include <iostream>

-#include <sstream>

 
 #include <sys/stat.h>
 #include <stdlib.h>
 
 #include <sys/stat.h>
 #include <stdlib.h>


@@ -34,9 +34,7 @@
 #include <signal.h>
 #include <stdio.h>
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 #include <errno.h>

-#include <sys/types.h>
-#include <pwd.h>
-#include <grp.h>
+#include <sstream>

 
 #include <apti18n.h>
                                                                        /*}}}*/
 
 #include <apti18n.h>
                                                                        /*}}}*/


@@ -44,34 +42,16 @@
 using namespace std;
 
 // Worker::Worker - Constructor for Queue startup                      /*{{{*/
 using namespace std;
 
 // Worker::Worker - Constructor for Queue startup                      /*{{{*/

-// ---------------------------------------------------------------------
-/* */
-pkgAcquire::Worker::Worker(Queue *Q,MethodConfig *Cnf,
-                          pkgAcquireStatus *Log) : Log(Log)
+pkgAcquire::Worker::Worker(Queue *Q, MethodConfig *Cnf, pkgAcquireStatus *log) :
+   d(NULL), OwnerQ(Q), Log(log), Config(Cnf), Access(Cnf->Access),
+   CurrentItem(nullptr), CurrentSize(0), TotalSize(0)

 {
 {

-   OwnerQ = Q;
-   Config = Cnf;
-   Access = Cnf->Access;
-   CurrentItem = 0;
-   TotalSize = 0;
-   CurrentSize = 0;
-

    Construct();
 }
                                                                        /*}}}*/
 // Worker::Worker - Constructor for method config startup              /*{{{*/
    Construct();
 }
                                                                        /*}}}*/
 // Worker::Worker - Constructor for method config startup              /*{{{*/

-// ---------------------------------------------------------------------
-/* */
-pkgAcquire::Worker::Worker(MethodConfig *Cnf)
+pkgAcquire::Worker::Worker(MethodConfig *Cnf) : Worker(nullptr, Cnf, nullptr)

 {
 {

-   OwnerQ = 0;
-   Config = Cnf;
-   Access = Cnf->Access;
-   CurrentItem = 0;
-   TotalSize = 0;
-   CurrentSize = 0;
-
-   Construct();

 }
                                                                        /*}}}*/
 // Worker::Construct - Constructor helper                              /*{{{*/
 }
                                                                        /*}}}*/
 // Worker::Construct - Constructor helper                              /*{{{*/


@@ -192,6 +172,25 @@ bool pkgAcquire::Worker::ReadMessages()
 // ---------------------------------------------------------------------
 /* This takes the messages from the message queue and runs them through
    the parsers in order. */
 // ---------------------------------------------------------------------
 /* This takes the messages from the message queue and runs them through
    the parsers in order. */

+enum class APT_HIDDEN MessageType {
+   CAPABILITIES = 100,
+   LOG = 101,
+   STATUS = 102,
+   REDIRECT = 103,
+   WARNING = 104,
+   URI_START = 200,
+   URI_DONE = 201,
+   URI_FAILURE = 400,
+   GENERAL_FAILURE = 401,
+   MEDIA_CHANGE = 403
+};
+static bool isDoomedItem(pkgAcquire::Item const * const Itm)
+{
+   auto const TransItm = dynamic_cast<pkgAcqTransactionItem const * const>(Itm);
+   if (TransItm == nullptr)
+      return false;
+   return TransItm->TransactionManager->State != pkgAcqTransactionItem::TransactionStarted;
+}

 bool pkgAcquire::Worker::RunMessages()
 {
    while (MessageQueue.empty() == false)
 bool pkgAcquire::Worker::RunMessages()
 {
    while (MessageQueue.empty() == false)


@@ -204,88 +203,106 @@ bool pkgAcquire::Worker::RunMessages()
 
       // Fetch the message number
       char *End;
 
       // Fetch the message number
       char *End;

-      int Number = strtol(Message.c_str(),&End,10);
+      MessageType const Number = static_cast<MessageType>(strtoul(Message.c_str(),&End,10));

       if (End == Message.c_str())
         return _error->Error("Invalid message from method %s: %s",Access.c_str(),Message.c_str());
 
       string URI = LookupTag(Message,"URI");
       if (End == Message.c_str())
         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);
 
       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)
       {
       }
 
       // Determine the message number and dispatch
       switch (Number)
       {

-        // 100 Capabilities
-        case 100:
+        case MessageType::CAPABILITIES:

         if (Capabilities(Message) == false)
            return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
         break;
 
         if (Capabilities(Message) == false)
            return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
         break;
 

-        // 101 Log
-        case 101:
+        case MessageType::LOG:

         if (Debug == true)
            clog << " <- (log) " << LookupTag(Message,"Message") << endl;
         break;
 
         if (Debug == true)
            clog << " <- (log) " << LookupTag(Message,"Message") << endl;
         break;
 

-        // 102 Status
-        case 102:
+        case MessageType::STATUS:

         Status = LookupTag(Message,"Message");
         break;
 
         Status = LookupTag(Message,"Message");
         break;
 

-         // 103 Redirect
-         case 103:
+        case MessageType::REDIRECT:

          {
          {

-            if (Itm == 0)
+            if (Itm == nullptr)

             {
                _error->Error("Method gave invalid 103 Redirect message");
                break;
             }
 
             {
                _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();
 
            // Change the status so that it can be dequeued
             Itm->URI = NewURI;
 
            ItemDone();
 
            // Change the status so that it can be dequeued

-           for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
-           {
-              pkgAcquire::Item *Owner = *O;
-              Owner->Status = pkgAcquire::Item::StatIdle;
-           }
+           for (auto const &O: Itm->Owners)
+              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);
            // 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);

-           Itm = NULL;
-           for (pkgAcquire::Queue::QItem::owner_iterator O = ItmOwners.begin(); O != ItmOwners.end(); ++O)
+           Itm = nullptr;
+           for (auto const &Owner: ItmOwners)

            {
            {

-              pkgAcquire::Item *Owner = *O;
-              pkgAcquire::ItemDesc desc = Owner->GetItemDesc();
-              desc.URI = NewURI;
-              OwnerQ->Owner->Enqueue(desc);
+              pkgAcquire::ItemDesc &desc = Owner->GetItemDesc();
+              if (Log != nullptr)
+                 Log->Done(desc);

 
 

-              if (Log != 0)
-                 Log->Done(Owner->GetItemDesc());
+              // if we change site, treat it as a mirror change
+              if (URI::SiteOnly(NewURI) != URI::SiteOnly(desc.URI))
+              {
+                 auto const firstSpace = desc.Description.find(" ");
+                 if (firstSpace != std::string::npos)
+                 {
+                    std::string const OldSite = desc.Description.substr(0, firstSpace);
+                    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);
+                          desc.Description.replace(0, firstSpace, Owner->UsedMirror);
+                       }
+                    }
+                 }
+              }
+              desc.URI = NewURI;
+              if (isDoomedItem(Owner) == false)
+                 OwnerQ->Owner->Enqueue(desc);

            }
             break;
          }
 
            }
             break;
          }
 

-        // 200 URI Start
-        case 200:
+        case MessageType::WARNING:
+           _error->Warning("%s: %s", Itm->Owner->DescURI().c_str(), LookupTag(Message,"Message").c_str());
+           break;
+
+        case MessageType::URI_START:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               _error->Error("Method gave invalid 200 URI Start message");
               break;
            {
               _error->Error("Method gave invalid 200 URI Start message");
               break;


@@ -295,26 +312,24 @@ bool pkgAcquire::Worker::RunMessages()
            CurrentSize = 0;
            TotalSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
            ResumePoint = strtoull(LookupTag(Message,"Resume-Point","0").c_str(), NULL, 10);
            CurrentSize = 0;
            TotalSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
            ResumePoint = strtoull(LookupTag(Message,"Resume-Point","0").c_str(), NULL, 10);

-           for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+           for (auto const Owner: Itm->Owners)

            {
            {

-              (*O)->Start(Message, TotalSize);
-
+              Owner->Start(Message, TotalSize);

               // Display update before completion
               // Display update before completion

-              if (Log != 0)
+              if (Log != nullptr)

               {
                  if (Log->MorePulses == true)
               {
                  if (Log->MorePulses == true)

-                    Log->Pulse((*O)->GetOwner());
-                 Log->Fetch((*O)->GetItemDesc());
+                    Log->Pulse(Owner->GetOwner());
+                 Log->Fetch(Owner->GetItemDesc());

               }
            }
 
            break;
         }
 
               }
            }
 
            break;
         }
 

-        // 201 URI Done
-        case 201:
+        case MessageType::URI_DONE:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               _error->Error("Method gave invalid 201 URI Done message");
               break;
            {
               _error->Error("Method gave invalid 201 URI Done message");
               break;


@@ -327,9 +342,10 @@ bool pkgAcquire::Worker::RunMessages()
               for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
                  Log->Pulse((*O)->GetOwner());
 
               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 ReceivedHashes;
            {

+              std::string const givenfilename = LookupTag(Message, "Filename");
+              std::string const filename = givenfilename.empty() ? Itm->Owner->DestFile : givenfilename;

               // see if we got hashes to verify
               for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
               {
               // see if we got hashes to verify
               for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
               {


@@ -350,11 +366,11 @@ bool pkgAcquire::Worker::RunMessages()
                     ReceivedHashes = calc.GetHashStringList();
                  }
               }
                     ReceivedHashes = calc.GetHashStringList();
                  }
               }

-           }

 
 

-           // 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()));
+              // only local files can refer other filenames and counting them as fetched would be unfair
+              if (Log != NULL && Itm->Owner->Complete == false && Itm->Owner->Local == false && givenfilename == filename)
+                 Log->Fetched(ReceivedHashes.FileSize(),atoi(LookupTag(Message,"Resume-Point","0").c_str()));
+           }

 
            std::vector<Item*> const ItmOwners = Itm->Owners;
            OwnerQ->ItemDone(Itm);
 
            std::vector<Item*> const ItmOwners = Itm->Owners;
            OwnerQ->ItemDone(Itm);


@@ -362,9 +378,9 @@ bool pkgAcquire::Worker::RunMessages()
 
            bool const isIMSHit = StringToBool(LookupTag(Message,"IMS-Hit"),false) ||
               StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false);
 
            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)
+           auto const forcedHash = _config->Find("Acquire::ForceHash");
+           for (auto const Owner: ItmOwners)

            {
            {

-              pkgAcquire::Item * const Owner = *O;

               HashStringList const ExpectedHashes = Owner->GetExpectedHashes();
               if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
               {
               HashStringList const ExpectedHashes = Owner->GetExpectedHashes();
               if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
               {


@@ -380,9 +396,10 @@ bool pkgAcquire::Worker::RunMessages()
 
               // decide if what we got is what we expected
               bool consideredOkay = false;
 
               // decide if what we got is what we expected
               bool consideredOkay = false;

-              if (ExpectedHashes.usable())
+              if ((forcedHash.empty() && ExpectedHashes.empty() == false) ||
+                    (forcedHash.empty() == false && ExpectedHashes.usable()))

               {
               {

-                 if (ReceivedHashes.usable() == false)
+                 if (ReceivedHashes.empty())

                  {
                     /* 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
                  {
                     /* 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


@@ -395,17 +412,20 @@ bool pkgAcquire::Worker::RunMessages()
                     consideredOkay = false;
 
               }
                     consideredOkay = false;
 
               }

-              else if (Owner->HashesRequired() == true)
-                 consideredOkay = false;

               else
               else

-                 consideredOkay = true;
+                 consideredOkay = !Owner->HashesRequired();

 
               if (consideredOkay == true)
 
               if (consideredOkay == true)

-              {
-                 Owner->Done(Message, ReceivedHashes, Config);
+                 consideredOkay = Owner->VerifyDone(Message, Config);
+              else // hashsum mismatch
+                 Owner->Status = pkgAcquire::Item::StatAuthError;

 
 

-                 // Log that we are done
-                 if (Log != 0)
+
+              if (consideredOkay == true)
+              {
+                 if (isDoomedItem(Owner) == false)
+                    Owner->Done(Message, ReceivedHashes, Config);
+                 if (Log != nullptr)

                  {
                     if (isIMSHit)
                        Log->IMSHit(Owner->GetItemDesc());
                  {
                     if (isIMSHit)
                        Log->IMSHit(Owner->GetItemDesc());


@@ -415,10 +435,18 @@ bool pkgAcquire::Worker::RunMessages()
               }
               else
               {
               }
               else
               {

-                 Owner->Status = pkgAcquire::Item::StatAuthError;
-                 Owner->Failed(Message,Config);
-
-                 if (Log != 0)
+                 if (isDoomedItem(Owner) == false)
+                 {
+                    if (Message.find("\nFailReason:") == std::string::npos)
+                    {
+                       if (ReceivedHashes != ExpectedHashes)
+                          Message.append("\nFailReason: HashSumMismatch");
+                       else
+                          Message.append("\nFailReason: WeakHashSums");
+                    }
+                    Owner->Failed(Message,Config);
+                 }
+                 if (Log != nullptr)

                     Log->Fail(Owner->GetItemDesc());
               }
            }
                     Log->Fail(Owner->GetItemDesc());
               }
            }


@@ -426,10 +454,9 @@ bool pkgAcquire::Worker::RunMessages()
            break;
         }
 
            break;
         }
 

-        // 400 URI Failure
-        case 400:
+        case MessageType::URI_FAILURE:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               std::string const msg = LookupTag(Message,"Message");
               _error->Error("Method gave invalid 400 URI Failure message: %s", msg.c_str());
            {
               std::string const msg = LookupTag(Message,"Message");
               _error->Error("Method gave invalid 400 URI Failure message: %s", msg.c_str());


@@ -439,40 +466,51 @@ bool pkgAcquire::Worker::RunMessages()
            PrepareFiles("400::URIFailure", Itm);
 
            // Display update before completion
            PrepareFiles("400::URIFailure", Itm);
 
            // Display update before completion

-           if (Log != 0 && Log->MorePulses == true)
+           if (Log != nullptr && Log->MorePulses == true)

               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);
               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;
+           Itm = nullptr;

 
 

-           for (pkgAcquire::Queue::QItem::owner_iterator O = ItmOwners.begin(); O != ItmOwners.end(); ++O)
+           bool errTransient = false, errAuthErr = false;

            {
            {

-              // 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;
+              std::string const failReason = LookupTag(Message, "FailReason");
+              {
+                 auto const reasons = { "Timeout", "ConnectionRefused",
+                    "ConnectionTimedOut", "ResolveFailure", "TmpResolveFailure" };
+                 errTransient = std::find(std::begin(reasons), std::end(reasons), failReason) != std::end(reasons);
+              }
+              if (errTransient == false)
+              {
+                 auto const reasons = { "HashSumMismatch", "WeakHashSums", "MaximumSizeExceeded" };
+                 errAuthErr = std::find(std::begin(reasons), std::end(reasons), failReason) != std::end(reasons);
+              }
+           }

 
 

-              (*O)->Failed(Message,Config);
+           for (auto const Owner: ItmOwners)
+           {
+              if (errAuthErr && Owner->GetExpectedHashes().empty() == false)
+                 Owner->Status = pkgAcquire::Item::StatAuthError;
+              else if (errTransient)
+                 Owner->Status = pkgAcquire::Item::StatTransientNetworkError;

 
 

-              if (Log != 0)
-                 Log->Fail((*O)->GetItemDesc());
+              if (isDoomedItem(Owner) == false)
+                 Owner->Failed(Message,Config);
+              if (Log != nullptr)
+                 Log->Fail(Owner->GetItemDesc());

            }
            ItemDone();
 
            break;
         }
 
            }
            ItemDone();
 
            break;
         }
 

-        // 401 General Failure
-        case 401:
+        case MessageType::GENERAL_FAILURE:

         _error->Error("Method %s General failure: %s",Access.c_str(),LookupTag(Message,"Message").c_str());
         break;
 
         _error->Error("Method %s General failure: %s",Access.c_str(),LookupTag(Message,"Message").c_str());
         break;
 

-        // 403 Media Change
-        case 403:
+        case MessageType::MEDIA_CHANGE:

         MediaChange(Message);
         break;
       }
         MediaChange(Message);
         break;
       }


@@ -526,7 +564,7 @@ bool pkgAcquire::Worker::MediaChange(string Message)
       ostringstream msg,status;
       ioprintf(msg,_("Please insert the disc labeled: "
                     "'%s' "
       ostringstream msg,status;
       ioprintf(msg,_("Please insert the disc labeled: "
                     "'%s' "

-                    "in the drive '%s' and press enter."),
+                    "in the drive '%s' and press [Enter]."),

               Media.c_str(),Drive.c_str());
       status << "media-change: "  // message
             << Media  << ":"     // media
               Media.c_str(),Drive.c_str());
       status << "media-change: "  // message
             << Media  << ":"     // media


@@ -593,12 +631,36 @@ bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
    if (OutFd == -1)
       return false;
 
    if (OutFd == -1)
       return false;
 

+   HashStringList const hsl = Item->GetExpectedHashes();
+
+   if (isDoomedItem(Item->Owner))
+      return true;
+
+   if (hsl.usable() == false && Item->Owner->HashesRequired() &&
+        _config->Exists("Acquire::ForceHash") == false)
+   {
+      std::string const Message = "400 URI Failure"
+        "\nURI: " + Item->URI +
+        "\nFilename: " + Item->Owner->DestFile +
+        "\nFailReason: WeakHashSums";
+
+      auto const ItmOwners = Item->Owners;
+      for (auto &O: ItmOwners)
+      {
+        O->Status = pkgAcquire::Item::StatAuthError;
+        O->Failed(Message, Config);
+        if (Log != nullptr)
+           Log->Fail(O->GetItemDesc());
+      }
+      // "queued" successfully, the item just instantly failed
+      return true;
+   }
+

    string Message = "600 URI Acquire\n";
    Message.reserve(300);
    Message += "URI: " + Item->URI;
    Message += "\nFilename: " + Item->Owner->DestFile;
 
    string Message = "600 URI Acquire\n";
    Message.reserve(300);
    Message += "URI: " + Item->URI;
    Message += "\nFilename: " + Item->Owner->DestFile;
 

-   HashStringList const hsl = Item->GetExpectedHashes();

    for (HashStringList::const_iterator hs = hsl.begin(); hs != hsl.end(); ++hs)
       Message += "\nExpected-" + hs->HashType() + ": " + hs->HashValue();
 
    for (HashStringList::const_iterator hs = hsl.begin(); hs != hsl.end(); ++hs)
       Message += "\nExpected-" + hs->HashType() + ": " + hs->HashValue();
 


@@ -619,7 +681,7 @@ bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
 
    if (RealFileExists(Item->Owner->DestFile))
    {
 
    if (RealFileExists(Item->Owner->DestFile))
    {

-      std::string SandboxUser = _config->Find("APT::Sandbox::User");
+      std::string const SandboxUser = _config->Find("APT::Sandbox::User");

       ChangeOwnerAndPermissionOfFile("Item::QueueURI", Item->Owner->DestFile.c_str(),
                                      SandboxUser.c_str(), "root", 0600);
    }
       ChangeOwnerAndPermissionOfFile("Item::QueueURI", Item->Owner->DestFile.c_str(),
                                      SandboxUser.c_str(), "root", 0600);
    }


@@ -722,12 +784,12 @@ void pkgAcquire::Worker::PrepareFiles(char const * const caller, pkgAcquire::Que
       for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
       {
         pkgAcquire::Item const * const Owner = *O;
       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)
+        if (Owner->DestFile == filename || filename == "/dev/null")

            continue;
            continue;

-        unlink(Owner->DestFile.c_str());
+        RemoveFile("PrepareFiles", Owner->DestFile);

         if (link(filename.c_str(), Owner->DestFile.c_str()) != 0)
         {
         if (link(filename.c_str(), Owner->DestFile.c_str()) != 0)
         {

-           // diferent mounts can't happen for us as we download to lists/ by default,
+           // 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
            // 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


@@ -739,7 +801,7 @@ void pkgAcquire::Worker::PrepareFiles(char const * const caller, pkgAcquire::Que
    else
    {
       for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
    else
    {
       for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)

-        unlink((*O)->DestFile.c_str());
+        RemoveFile("PrepareFiles", (*O)->DestFile);

    }
 }
                                                                        /*}}}*/
    }
 }
                                                                        /*}}}*/