this cleaned up functions and global constants and hid them away in to their header and source files

tarconst.h

@@ -0,0 +1,40 @@
+/* this headerfile contains global constant variables needed during parsing of a tar file
+ *
+ * by Marcel Nowicki (github@epenis.de | github.com/blindi0815)
+ */
+
+#ifndef TARSTATS___TARCONST_H
+#define TARSTATS___TARCONST_H
+
+#include <string>
+#include <utility>
+
+namespace tarconstant {
+    // global itemtype definition
+    inline std::string const typeFile = "FILES";
+    inline std::string const typeDir = "DIRECTORIES";
+    inline std::string const typeSym = "SYMLINKS";
+    inline std::string const typeHard = "HARDLINKS";
+    inline std::string const typeOther = "OTHER";
+
+    // valid magicfield
+    inline std::string const mgcfield = "ustar";
+
+    // Byte offsets
+    inline uint16_t blocksize = 512; // tar consists of continuous 512 Byte data blocks
+    inline uint8_t itemtypeByte = 156;
+    inline std::pair<uint16_t, uint8_t> mgcfieldByte {257,6};      // { offset , length }
+    inline std::pair<uint8_t , uint8_t> itemoctlnByte {124,11};    // at offset 124 because first byte
+                                                                        // marks octal or base256 coding
+    inline std::string helptext
+            {"usage: tarstats-pp [-h] [-j] [-f] tarfile.\n"
+             "A tool to calculate basics statistics on tarball. Shamelessly inspired by github.com/isotopp/tarstats!\n\n"
+             "mandatory argument:\n"
+             "tarfile   a tarfile to calculate stats on\n\n"
+             "optional arguments\n"
+             "-h        this helptext\n"
+             "-j        stats in JSON format printed to stdout\n"
+             "-f        print stats to file <tarfilename>.txt or .json if -j invoked"};
+}
+
+#endif //TARSTATS___TARCONST_H