Allow the FileFd to use an external Compressor to uncompress a given file

internally so that it is exported and can be used like a "normal"
uncompressed file with FileFd

This allows us to hide th zlib usage in the implementation and use gzip
instead if we don't have zlib builtin (the same for other compressors).

The code includes quiet a few FIXME's so while all tests are working
it shouldn't be used just yet outside of libapt as it might break.

2 files changed, 4 insertions, 72 deletions

diff --git a/ftparchive/multicompress.cc b/ftparchive/multicompress.cc
index bf0f858d9..37a713efd 100644
--- a/ftparchive/multicompress.cc
+++ b/ftparchive/multicompress.cc
@@ -16,6 +16,7 @@
 // Include Files							/*{{{*/
 #include <config.h>
 
+#include <apt-pkg/fileutl.h>
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/md5.h>
@@ -261,73 +262,6 @@ bool MultiCompress::Finalize(unsigned long long &OutSize)
    return true;
 }
 									/*}}}*/
-// MultiCompress::OpenCompress - Open the compressor			/*{{{*/
-// ---------------------------------------------------------------------
-/* This opens the compressor, either in compress mode or decompress 
-   mode. FileFd is always the compressor input/output file, 
-   OutFd is the created pipe, Input for Compress, Output for Decompress. */
-bool MultiCompress::OpenCompress(APT::Configuration::Compressor const &Prog,
-				 pid_t &Pid,int const &FileFd,int &OutFd,bool const &Comp)
-{
-   Pid = -1;
-   
-   // No compression
-   if (Prog.Binary.empty() == true)
-   {
-      OutFd = dup(FileFd);
-      return true;
-   }
-      
-   // Create a data pipe
-   int Pipe[2] = {-1,-1};
-   if (pipe(Pipe) != 0)
-      return _error->Errno("pipe",_("Failed to create subprocess IPC"));
-   for (int J = 0; J != 2; J++)
-      SetCloseExec(Pipe[J],true);
-
-   if (Comp == true)
-      OutFd = Pipe[1];
-   else
-      OutFd = Pipe[0];
-   
-   // The child..
-   Pid = ExecFork();
-   if (Pid == 0)
-   {
-      if (Comp == true)
-      {
-	 dup2(FileFd,STDOUT_FILENO);
-	 dup2(Pipe[0],STDIN_FILENO);
-      }   
-      else
-      {
-	 dup2(FileFd,STDIN_FILENO);
-	 dup2(Pipe[1],STDOUT_FILENO);
-      }
-      
-      SetCloseExec(STDOUT_FILENO,false);
-      SetCloseExec(STDIN_FILENO,false);
-
-      std::vector<char const*> Args;
-      Args.push_back(Prog.Binary.c_str());
-      std::vector<std::string> const * const addArgs =
-		(Comp == true) ? &(Prog.CompressArgs) : &(Prog.UncompressArgs);
-      for (std::vector<std::string>::const_iterator a = addArgs->begin();
-	   a != addArgs->end(); ++a)
-	 Args.push_back(a->c_str());
-      Args.push_back(NULL);
-
-      execvp(Args[0],(char **)&Args[0]);
-      cerr << _("Failed to exec compressor ") << Args[0] << endl;
-      _exit(100);
-   };      
-   if (Comp == true)
-      close(Pipe[0]);
-   else
-      close(Pipe[1]);
-   return true;
-}
-									/*}}}*/
 // MultiCompress::OpenOld - Open an old file				/*{{{*/
 // ---------------------------------------------------------------------
 /* This opens one of the original output files, possibly decompressing it. */
@@ -344,7 +278,7 @@ bool MultiCompress::OpenOld(int &Fd,pid_t &Proc)
       return false;
    
    // Decompress the file so we can read it
-   if (OpenCompress(Best->CompressProg,Proc,F.Fd(),Fd,false) == false)
+   if (ExecCompressor(Best->CompressProg,&Proc,F.Fd(),Fd,false) == false)
       return false;
    
    return true;
@@ -374,8 +308,8 @@ bool MultiCompress::Child(int const &FD)
    // Start the compression children.
    for (Files *I = Outputs; I != 0; I = I->Next)
    {
-      if (OpenCompress(I->CompressProg,I->CompressProc,I->TmpFile.Fd(),
-		       I->Fd,true) == false)
+      if (ExecCompressor(I->CompressProg,&(I->CompressProc),I->TmpFile.Fd(),
+			 I->Fd,true) == false)
 	 return false;      
    }
 
diff --git a/ftparchive/multicompress.h b/ftparchive/multicompress.h
index 5496b06d0..ac8bd0746 100644
--- a/ftparchive/multicompress.h
+++ b/ftparchive/multicompress.h
@@ -41,8 +41,6 @@ class MultiCompress
    pid_t Outputter;
    mode_t Permissions;
 
-   bool OpenCompress(APT::Configuration::Compressor const &Prog,
-		     pid_t &Pid,int const &FileFd, int &OutFd,bool const &Comp);
    bool Child(int const &Fd);
    bool Start();
    bool Die();