Add 'dist-clean' command to remove packages and list files

We assume all files in the 'listsdir' are candidates. Keep only files
ending with Release, Release.gpg, and InRelease.

Closes: #959093

1 files changed, 23 insertions, 0 deletions

diff --git a/apt-pkg/acquire.h b/apt-pkg/acquire.h
index 17b68768e..46115a27f 100644
--- a/apt-pkg/acquire.h
+++ b/apt-pkg/acquire.h
@@ -70,6 +70,7 @@
 #include <apt-pkg/weakptr.h>
 
 #include <chrono>
+#include <functional>
 #include <string>
 #include <vector>
 
@@ -330,6 +331,14 @@ class APT_PUBLIC pkgAcquire
     *  \return \b true if the directory exists and is readable.
     */
    bool Clean(std::string Dir);
+   
+   /** Deletes each package list and index file in the given directory.
+    *
+    *  \param Dir The directory to be cleaned.
+    *
+    *  \return \b true if the directory exists and is readable.
+    */
+   bool CleanLists(std::string Dir);
 
    /** \return the total size in bytes of all the items included in
     *  this download.
@@ -372,6 +381,20 @@ class APT_PUBLIC pkgAcquire
 
    private:
    APT_HIDDEN void Initialize();
+
+   /** Delete each entry in the given directory whose name does \em not match
+    *  a criterion.
+    *
+    *  \param Dir The directory to be cleaned.
+    *
+    *  \param KeepP A predicate telling to keep the named file; if it is
+    *  non-empty and returns true, the file is kept.
+    *
+    *  \param Caller Log name of the caller.
+    *
+    *  \return \b true if the directory exists and is readable.
+    */
+   APT_HIDDEN static bool CleanDir(std::string Dir, std::function<bool(char const*)> const &KeepP, char const * const Caller);
 };
 
 /** \brief Represents a single download source from which an item