You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 

278 lines
9.2 KiB

// -*- mode: cpp; mode: fold -*-
// Description /*{{{*/
// $Id: debfile.cc,v 1.3.2.1 2004/01/16 18:58:50 mdz 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 /*{{{*/
#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>
#include <apti18n.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;
if (!CheckMember("debian-binary")) {
_error->Error(_("This is not a valid DEB archive, missing '%s' member"), "debian-binary");
return;
}
if (!CheckMember("control.tar.gz")) {
_error->Error(_("This is not a valid DEB archive, missing '%s' member"), "control.tar.gz");
return;
}
if (!CheckMember("data.tar.gz") &&
!CheckMember("data.tar.bz2") &&
!CheckMember("data.tar.lzma")) {
_error->Error(_("This is not a valid DEB archive, it has no '%s', '%s' or '%s' member"), "data.tar.gz", "data.tar.bz2", "data.tar.lzma");
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 false;
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)
{
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,"gzip");
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");
const char *Compressor = "gzip";
if (Member == 0) {
Member = AR.FindMember("data.tar.bz2");
Compressor = "bzip2";
}
if (Member == 0) {
Member = AR.FindMember("data.tar.lzma");
Compressor = "lzma";
}
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,Compressor);
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,"gzip");
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(_("Unparsable 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);
}
/*}}}*/