Use some semantically more correct buffer operations

[apt.git] / apt-inst / contrib / extracttar.cc

diff --git a/apt-inst/contrib/extracttar.cc b/apt-inst/contrib/extracttar.cc
index 01b6b38360bd61dd1dcfe505aed9a9312b0dc47f..60360053ed394364fda36b074a8355405423e6da 100644 (file)
--- a/apt-inst/contrib/extracttar.cc
+++ b/apt-inst/contrib/extracttar.cc
@@ -6,7 +6,7 @@
    Extract a Tar - Tar Extractor
 
    Some performance measurements showed that zlib performed quite poorly
    Extract a Tar - Tar Extractor
 
    Some performance measurements showed that zlib performed quite poorly

-   in comparision to a forked gzip process. This tar extractor makes use
+   in comparison to a forked gzip process. This tar extractor makes use

    of the fact that dup'd file descriptors have the same seek pointer
    and that gzip will not read past the end of a compressed stream, 
    even if there is more data. We use the dup property to track extraction
    of the fact that dup'd file descriptors have the same seek pointer
    and that gzip will not read past the end of a compressed stream, 
    even if there is more data. We use the dup property to track extraction


@@ -16,18 +16,23 @@
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/

-#include <apt-pkg/extracttar.h>
+#include<config.h>

 
 

+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/extracttar.h>

 #include <apt-pkg/error.h>
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/configuration.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/configuration.h>

-#include <apt-pkg/macros.h>
+#include <apt-pkg/fileutl.h>

 
 

-#include <stdlib.h>
+#include <string.h>
+#include <algorithm>
+#include <string>

 #include <unistd.h>
 #include <signal.h>
 #include <fcntl.h>
 #include <iostream>
 #include <unistd.h>
 #include <signal.h>
 #include <fcntl.h>
 #include <iostream>

+

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


@@ -55,12 +60,10 @@ struct ExtractTar::TarHeader
 // ExtractTar::ExtractTar - Constructor                                        /*{{{*/
 // ---------------------------------------------------------------------
 /* */
 // ExtractTar::ExtractTar - Constructor                                        /*{{{*/
 // ---------------------------------------------------------------------
 /* */

-ExtractTar::ExtractTar(FileFd &Fd,unsigned long Max,string DecompressionProgram) : File(Fd), 
-                         MaxInSize(Max), DecompressProg(DecompressionProgram)
-
+ExtractTar::ExtractTar(FileFd &Fd,unsigned long long Max,string DecompressionProgram)
+       : File(Fd), MaxInSize(Max), DecompressProg(DecompressionProgram)

 {
    GZPid = -1;
 {
    GZPid = -1;

-   InFd = -1;

    Eof = false;
 }
                                                                        /*}}}*/
    Eof = false;
 }
                                                                        /*}}}*/


@@ -70,36 +73,17 @@ ExtractTar::ExtractTar(FileFd &Fd,unsigned long Max,string DecompressionProgram)
 ExtractTar::~ExtractTar()
 {
    // Error close
 ExtractTar::~ExtractTar()
 {
    // Error close

-   Done(true);
+   Done();

 }
                                                                        /*}}}*/
 // ExtractTar::Done - Reap the gzip sub process                                /*{{{*/
 }
                                                                        /*}}}*/
 // ExtractTar::Done - Reap the gzip sub process                                /*{{{*/

-// ---------------------------------------------------------------------
-/* If the force flag is given then error messages are suppressed - this
-   means we hit the end of the tar file but there was still gzip data. */
-bool ExtractTar::Done(bool Force)
+bool ExtractTar::Done(bool)

 {
 {

-   InFd.Close();
-   if (GZPid <= 0)
-      return true;
-
-   /* If there is a pending error then we are cleaning up gzip and are
-      not interested in it's failures */
-   if (_error->PendingError() == true)
-      Force = true;
-   
-   // Make sure we clean it up!
-   kill(GZPid,SIGINT);
-   string confvar = string("dir::bin::") + DecompressProg;
-   if (ExecWait(GZPid,_config->Find(confvar.c_str(),DecompressProg.c_str()).c_str(),
-               Force) == false)
-   {
-      GZPid = -1;
-      return Force;
-   }
-   
-   GZPid = -1;
-   return true;
+   return Done();
+}
+bool ExtractTar::Done()
+{
+   return InFd.Close();

 }
                                                                        /*}}}*/
 // ExtractTar::StartGzip - Startup gzip                                        /*{{{*/
 }
                                                                        /*}}}*/
 // ExtractTar::StartGzip - Startup gzip                                        /*{{{*/


@@ -109,43 +93,23 @@ bool ExtractTar::Done(bool Force)
    gzip will efficiently ignore the extra bits. */
 bool ExtractTar::StartGzip()
 {
    gzip will efficiently ignore the extra bits. */
 bool ExtractTar::StartGzip()
 {

-   int Pipes[2];
-   if (pipe(Pipes) != 0)
-      return _error->Errno("pipe",_("Failed to create pipes"));
-   
-   // Fork off the process
-   GZPid = ExecFork();
-
-   // Spawn the subprocess
-   if (GZPid == 0)
+   if (DecompressProg.empty())

    {
    {

-      // Setup the FDs
-      dup2(Pipes[1],STDOUT_FILENO);
-      dup2(File.Fd(),STDIN_FILENO);
-      int Fd = open("/dev/null",O_RDWR);
-      if (Fd == -1)
-        _exit(101);
-      dup2(Fd,STDERR_FILENO);
-      close(Fd);
-      SetCloseExec(STDOUT_FILENO,false);
-      SetCloseExec(STDIN_FILENO,false);      
-      SetCloseExec(STDERR_FILENO,false);
-      
-      const char *Args[3];
-      string confvar = string("dir::bin::") + DecompressProg;
-      string argv0 = _config->Find(confvar.c_str(),DecompressProg.c_str());
-      Args[0] = argv0.c_str();
-      Args[1] = "-d";
-      Args[2] = 0;
-      execvp(Args[0],(char **)Args);
-      cerr << _("Failed to exec gzip ") << Args[0] << endl;
-      _exit(100);
+      InFd.OpenDescriptor(File.Fd(), FileFd::ReadOnly, FileFd::None, false);
+      return true;

    }
 
    }
 

-   // Fix up our FDs
-   InFd.Fd(Pipes[0]);
-   close(Pipes[1]);
-   return true;
+   std::vector<APT::Configuration::Compressor> const compressors = APT::Configuration::getCompressors();
+   std::vector<APT::Configuration::Compressor>::const_iterator compressor = compressors.begin();
+   for (; compressor != compressors.end(); ++compressor) {
+      if (compressor->Name == DecompressProg) {
+        return InFd.OpenDescriptor(File.Fd(), FileFd::ReadOnly, *compressor, false);
+      }
+   }
+
+   return _error->Error(_("Cannot find a configured compressor for '%s'"),
+                       DecompressProg.c_str());
+

 }
                                                                        /*}}}*/
 // ExtractTar::Go - Perform extraction                                 /*{{{*/
 }
                                                                        /*}}}*/
 // ExtractTar::Go - Perform extraction                                 /*{{{*/


@@ -159,8 +123,8 @@ bool ExtractTar::Go(pkgDirStream &Stream)
       return false;
    
    // Loop over all blocks
       return false;
    
    // Loop over all blocks

-   string LastLongLink;
-   string LastLongName;
+   string LastLongLink, ItemLink;
+   string LastLongName, ItemName;

    while (1)
    {
       bool BadRecord = false;      
    while (1)
    {
       bool BadRecord = false;      


@@ -187,7 +151,7 @@ bool ExtractTar::Go(pkgDirStream &Stream)
       /* Check for a block of nulls - in this case we kill gzip, GNU tar
                 does this.. */
       if (NewSum == ' '*sizeof(Tar->Checksum))
       /* Check for a block of nulls - in this case we kill gzip, GNU tar
                 does this.. */
       if (NewSum == ' '*sizeof(Tar->Checksum))

-        return Done(true);
+        return Done();

       
       if (NewSum != CheckSum)
         return _error->Error(_("Tar checksum failed, archive corrupted"));
       
       if (NewSum != CheckSum)
         return _error->Error(_("Tar checksum failed, archive corrupted"));


@@ -206,25 +170,23 @@ bool ExtractTar::Go(pkgDirStream &Stream)
          StrToNum(Tar->Major,Itm.Major,sizeof(Tar->Major),8) == false ||
          StrToNum(Tar->Minor,Itm.Minor,sizeof(Tar->Minor),8) == false)
         return _error->Error(_("Corrupted archive"));
          StrToNum(Tar->Major,Itm.Major,sizeof(Tar->Major),8) == false ||
          StrToNum(Tar->Minor,Itm.Minor,sizeof(Tar->Minor),8) == false)
         return _error->Error(_("Corrupted archive"));

-      
-      // Grab the filename
+
+      // Grab the filename and link target: use last long name if one was
+      // set, otherwise use the header value as-is, but remember that it may
+      // fill the entire 100-byte block and needs to be zero-terminated.
+      // See Debian Bug #689582.

       if (LastLongName.empty() == false)
         Itm.Name = (char *)LastLongName.c_str();
       else
       if (LastLongName.empty() == false)
         Itm.Name = (char *)LastLongName.c_str();
       else

-      {
-        Tar->Name[sizeof(Tar->Name)-1] = 0;
-        Itm.Name = Tar->Name;
-      }      
+        Itm.Name = (char *)ItemName.assign(Tar->Name, sizeof(Tar->Name)).c_str();

       if (Itm.Name[0] == '.' && Itm.Name[1] == '/' && Itm.Name[2] != 0)
         Itm.Name += 2;
       if (Itm.Name[0] == '.' && Itm.Name[1] == '/' && Itm.Name[2] != 0)
         Itm.Name += 2;

-      
-      // Grab the link target
-      Tar->Name[sizeof(Tar->LinkName)-1] = 0;
-      Itm.LinkTarget = Tar->LinkName;

 
       if (LastLongLink.empty() == false)
         Itm.LinkTarget = (char *)LastLongLink.c_str();
 
       if (LastLongLink.empty() == false)
         Itm.LinkTarget = (char *)LastLongLink.c_str();

-      
+      else
+        Itm.LinkTarget = (char *)ItemLink.assign(Tar->LinkName, sizeof(Tar->LinkName)).c_str();
+

       // Convert the type over
       switch (Tar->LinkFlag)
       {
       // Convert the type over
       switch (Tar->LinkFlag)
       {


@@ -259,7 +221,7 @@ bool ExtractTar::Go(pkgDirStream &Stream)
 
         case GNU_LongLink:
         {
 
         case GNU_LongLink:
         {

-           unsigned long Length = Itm.Size;
+           unsigned long long Length = Itm.Size;

            unsigned char Block[512];
            while (Length > 0)
            {
            unsigned char Block[512];
            while (Length > 0)
            {


@@ -278,7 +240,7 @@ bool ExtractTar::Go(pkgDirStream &Stream)
         
         case GNU_LongName:
         {
         
         case GNU_LongName:
         {

-           unsigned long Length = Itm.Size;
+           unsigned long long Length = Itm.Size;

            unsigned char Block[512];
            while (Length > 0)
            {
            unsigned char Block[512];
            while (Length > 0)
            {


@@ -307,11 +269,11 @@ bool ExtractTar::Go(pkgDirStream &Stream)
            return false;
       
       // Copy the file over the FD
            return false;
       
       // Copy the file over the FD

-      unsigned long Size = Itm.Size;
+      unsigned long long Size = Itm.Size;

       while (Size != 0)
       {
         unsigned char Junk[32*1024];
       while (Size != 0)
       {
         unsigned char Junk[32*1024];

-        unsigned long Read = min(Size,(unsigned long)sizeof(Junk));
+        unsigned long Read = min(Size, (unsigned long long)sizeof(Junk));

         if (InFd.Read(Junk,((Read+511)/512)*512) == false)
            return false;
         
         if (InFd.Read(Junk,((Read+511)/512)*512) == false)
            return false;
         


@@ -344,6 +306,6 @@ bool ExtractTar::Go(pkgDirStream &Stream)
       LastLongLink.erase();
    }
    
       LastLongLink.erase();
    }
    

-   return Done(false);
+   return Done();

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