Recursively deleting directories during state sync. (#189)

src/util/util.cpp

@@ -314,6 +314,19 @@ namespace util
             1, FTW_PHYS);
     }
 
+    /**
+     * Remove a directory recursively with it's content. FTW_DEPTH is provided so all of the files and subdirectories within
+     * The path will be processed. FTW_PHYS is provided so symbolic links won't be followed.
+     */
+    int remove_directory_recursively(std::string_view dir_path)
+    {
+        return nftw(
+            dir_path.data(), [](const char *fpath, const struct stat *sb, int typeflag, struct FTW *ftwbuf) {
+                return remove(fpath);
+            },
+            1, FTW_DEPTH | FTW_PHYS);
+    }
+
     void split_string(std::vector<std::string> &collection, std::string_view str, std::string_view delimeter)
     {
         if (str.empty())