Join with aliencode

Author: jgg
Date: 2001-02-20 07:03:16 GMT
Join with aliencode

1 files changed, 262 insertions, 0 deletions

diff --git a/apt-inst/deb/debfile.cc b/apt-inst/deb/debfile.cc
new file mode 100644
index 000000000..c93ba88a8
--- /dev/null
+++ b/apt-inst/deb/debfile.cc
@@ -0,0 +1,262 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+// $Id: debfile.cc,v 1.2 2001/02/20 07:03:17 jgg Exp $
+/* ######################################################################
+
+   Debian Archive File (.deb)
+   
+   .DEB archives are AR files containing two tars and an empty marker
+   member called 'debian-binary'. The two tars contain the meta data and
+   the actual archive contents. Thus this class is a very simple wrapper
+   around ar/tar to simply extract the right tar files.
+   
+   It also uses the deb package list parser to parse the control file 
+   into the cache.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#ifdef __GNUG__
+#pragma implementation "apt-pkg/debfile.h"
+#endif
+
+#include <apt-pkg/debfile.h>
+#include <apt-pkg/extracttar.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/deblistparser.h>
+
+#include <sys/stat.h>
+#include <unistd.h>
+									/*}}}*/
+
+// DebFile::debDebFile - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* Open the AR file and check for consistency */
+debDebFile::debDebFile(FileFd &File) : File(File), AR(File)
+{
+   if (_error->PendingError() == true)
+      return;
+   
+   // Check the members for validity
+   if (CheckMember("debian-binary") == false ||
+       CheckMember("control.tar.gz") == false ||
+       CheckMember("data.tar.gz") == false)
+      return;
+}
+									/*}}}*/
+// DebFile::CheckMember - Check if a named member is in the archive	/*{{{*/
+// ---------------------------------------------------------------------
+/* This is used to check for a correct deb and to give nicer error messages
+   for people playing around. */
+bool debDebFile::CheckMember(const char *Name)
+{
+   if (AR.FindMember(Name) == 0)
+      return _error->Error("This is not a valid DEB archive, missing '%s' member",Name);
+   return true;
+}
+									/*}}}*/
+// DebFile::GotoMember - Jump to a Member				/*{{{*/
+// ---------------------------------------------------------------------
+/* Jump in the file to the start of a named member and return the information
+   about that member. The caller can then read from the file up to the 
+   returned size. Note, since this relies on the file position this is
+   a destructive operation, it also changes the last returned Member
+   structure - so don't nest them! */
+const ARArchive::Member *debDebFile::GotoMember(const char *Name)
+{
+   // Get the archive member and positition the file
+   const ARArchive::Member *Member = AR.FindMember(Name);
+   if (Member == 0)
+   {
+      _error->Error("Internal Error, could not locate member %s",Name);
+      return 0;
+   }
+   if (File.Seek(Member->Start) == false)
+      return 0;
+      
+   return Member;
+}
+									/*}}}*/
+// DebFile::ExtractControl - Extract Control information		/*{{{*/
+// ---------------------------------------------------------------------
+/* Extract the control information into the Database's temporary 
+   directory. */
+bool debDebFile::ExtractControl(pkgDataBase &DB)
+{
+   // Get the archive member and positition the file
+   const ARArchive::Member *Member = GotoMember("control.tar.gz");
+   if (Member == 0)
+      return false;
+      
+   // Prepare Tar
+   ControlExtract Extract;
+   ExtractTar Tar(File,Member->Size);
+   if (_error->PendingError() == true)
+      return false;
+   
+   // Get into the temporary directory
+   string Cwd = SafeGetCWD();
+   string Tmp;
+   if (DB.GetMetaTmp(Tmp) == false)
+      return false;
+   if (chdir(Tmp.c_str()) != 0)
+      return _error->Errno("chdir","Couldn't change to %s",Tmp.c_str());
+   
+   // Do extraction
+   if (Tar.Go(Extract) == false)
+      return false;
+   
+   // Switch out of the tmp directory.
+   if (chdir(Cwd.c_str()) != 0)
+      chdir("/");
+   
+   return true;
+}
+									/*}}}*/
+// DebFile::ExtractArchive - Extract the archive data itself		/*{{{*/
+// ---------------------------------------------------------------------
+/* Simple wrapper around tar.. */
+bool debDebFile::ExtractArchive(pkgDirStream &Stream)
+{
+   // Get the archive member and positition the file 
+   const ARArchive::Member *Member = AR.FindMember("data.tar.gz");
+   if (Member == 0)
+      return _error->Error("Internal Error, could not locate member");   
+   if (File.Seek(Member->Start) == false)
+      return false;
+      
+   // Prepare Tar
+   ExtractTar Tar(File,Member->Size);
+   if (_error->PendingError() == true)
+      return false;
+   return Tar.Go(Stream);
+}
+									/*}}}*/
+// DebFile::MergeControl - Merge the control information		/*{{{*/
+// ---------------------------------------------------------------------
+/* This reads the extracted control file into the cache and returns the
+   version that was parsed. All this really does is select the correct
+   parser and correct file to parse. */
+pkgCache::VerIterator debDebFile::MergeControl(pkgDataBase &DB)
+{
+   // Open the control file
+   string Tmp;
+   if (DB.GetMetaTmp(Tmp) == false)
+      return pkgCache::VerIterator(DB.GetCache());
+   FileFd Fd(Tmp + "control",FileFd::ReadOnly);
+   if (_error->PendingError() == true)
+      return pkgCache::VerIterator(DB.GetCache());
+   
+   // Parse it
+   debListParser Parse(&Fd);
+   pkgCache::VerIterator Ver(DB.GetCache());
+   if (DB.GetGenerator().MergeList(Parse,&Ver) == false)
+      return pkgCache::VerIterator(DB.GetCache());
+   
+   if (Ver.end() == true)
+      _error->Error("Failed to locate a valid control file");
+   return Ver;
+}
+									/*}}}*/
+
+// DebFile::ControlExtract::DoItem - Control Tar Extraction		/*{{{*/
+// ---------------------------------------------------------------------
+/* This directory stream handler for the control tar handles extracting
+   it into the temporary meta directory. It only extracts files, it does
+   not create directories, links or anything else. */
+bool debDebFile::ControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   if (Itm.Type != Item::File)
+      return true;
+   
+   /* Cleanse the file name, prevent people from trying to unpack into
+      absolute paths, .., etc */
+   for (char *I = Itm.Name; *I != 0; I++)
+      if (*I == '/')
+	 *I = '_';
+
+   /* Force the ownership to be root and ensure correct permissions, 
+      go-w, the rest are left untouched */
+   Itm.UID = 0;
+   Itm.GID = 0;
+   Itm.Mode &= ~(S_IWGRP | S_IWOTH);
+   
+   return pkgDirStream::DoItem(Itm,Fd);
+}
+									/*}}}*/
+
+// MemControlExtract::DoItem - Check if it is the control file		/*{{{*/
+// ---------------------------------------------------------------------
+/* This sets up to extract the control block member file into a memory 
+   block of just the right size. All other files go into the bit bucket. */
+bool debDebFile::MemControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   // At the control file, allocate buffer memory.
+   if (Member == Itm.Name)
+   {
+      delete [] Control;
+      Control = new char[Itm.Size+2];
+      IsControl = true;
+      Fd = -2; // Signal to pass to Process
+      Length = Itm.Size;
+   }   
+   else
+      IsControl = false;
+   
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Process - Process extracting the control file	/*{{{*/
+// ---------------------------------------------------------------------
+/* Just memcopy the block from the tar extractor and put it in the right
+   place in the pre-allocated memory block. */
+bool debDebFile::MemControlExtract::Process(Item &Itm,const unsigned char *Data,
+			     unsigned long Size,unsigned long Pos)
+{
+   memcpy(Control + Pos, Data,Size);
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Read - Read the control information from the deb	/*{{{*/
+// ---------------------------------------------------------------------
+/* This uses the internal tar extractor to fetch the control file, and then
+   it parses it into a tag section parser. */
+bool debDebFile::MemControlExtract::Read(debDebFile &Deb)
+{
+   // Get the archive member and positition the file 
+   const ARArchive::Member *Member = Deb.GotoMember("control.tar.gz");
+   if (Member == 0)
+      return false;
+
+   // Extract it.
+   ExtractTar Tar(Deb.GetFile(),Member->Size);
+   if (Tar.Go(*this) == false)
+      return false;
+
+   if (Control == 0)
+      return true;
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   if (Section.Scan(Control,Length+2) == false)
+      return _error->Error("Unparsible control file");
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::TakeControl - Parse a memory block		/*{{{*/
+// ---------------------------------------------------------------------
+/* The given memory block is loaded into the parser and parsed as a control
+   record. */
+bool debDebFile::MemControlExtract::TakeControl(const void *Data,unsigned long Size)
+{
+   delete [] Control;
+   Control = new char[Size+2];
+   Length = Size;
+   memcpy(Control,Data,Size);
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   return Section.Scan(Control,Length+2);
+}
+									/*}}}*/
+