1 files changed, 19 insertions, 0 deletions
diff --git a/src/libutil/tarfile.hh b/src/libutil/tarfile.hh
index 89a024f1d..4d9141fd4 100644
--- a/src/libutil/tarfile.hh
+++ b/src/libutil/tarfile.hh
@@ -1,7 +1,26 @@
 #include "serialise.hh"
+#include <archive.h>
 
 namespace nix {
 
+struct TarArchive {
+    struct archive * archive;
+    Source * source;
+    std::vector<unsigned char> buffer;
+
+    void check(int err, const std::string & reason = "failed to extract archive (%s)");
+
+    TarArchive(Source & source, bool raw = false);
+
+    TarArchive(const Path & path);
+
+    // disable copy constructor
+    TarArchive(const TarArchive &) = delete;
+
+    void close();
+
+    ~TarArchive();
+};
 void unpackTarfile(Source & source, const Path & destDir);
 
 void unpackTarfile(const Path & tarFile, const Path & destDir);