add a config option to switch uncompress methods to compress

Not very useful in the normal operation of work, but handy for tests.

Git-Dch: Ignore

methods/gzip.cc

@@ -11,6 +11,7 @@
 // Include Files							/*{{{*/
 #include <config.h>
 
+#include <apt-pkg/configuration.h>
 #include <apt-pkg/acquire-method.h>
 #include <apt-pkg/error.h>
 #include <apt-pkg/fileutl.h>
@@ -60,17 +61,25 @@ bool GzipMethod::Fetch(FetchItem *Itm)
       return _error->Error("Extraction of file %s requires unknown compressor %s", Path.c_str(), Prog);
 
    // Open the source and destination files
-   FileFd From;
-   From.Open(Path, FileFd::ReadOnly, *compressor);
-
-   if(From.FileSize() == 0)
-      return _error->Error(_("Empty files can't be valid archives"));
-
-   FileFd To(Itm->DestFile,FileFd::WriteAtomic);   
+   FileFd From, To;
+   if (_config->FindB("Method::Compress", false) == false)
+   {
+      From.Open(Path, FileFd::ReadOnly, *compressor);
+      if(From.FileSize() == 0)
+	 return _error->Error(_("Empty files can't be valid archives"));
+      To.Open(Itm->DestFile, FileFd::WriteAtomic);
+   }
+   else
+   {
+      From.Open(Path, FileFd::ReadOnly);
+      To.Open(Itm->DestFile, FileFd::WriteOnly | FileFd::Create | FileFd::Empty, *compressor);
+   }
    To.EraseOnFailure();
-   if (_error->PendingError() == true)
+
+   if (From.IsOpen() == false || From.Failed() == true ||
+	 To.IsOpen() == false || To.Failed() == true)
       return false;
-   
+
    // Read data from source, generate checksums and write
    Hashes Hash;
    bool Failed = false;