.. _program_listing_file_include_ndef-lite_util.hpp:

Program Listing for File util.hpp
=================================

|exhale_lsh| :ref:`Return to documentation for file <file_include_ndef-lite_util.hpp>` (``include/ndef-lite/util.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #ifndef UTIL_H
   #define UTIL_H
   
   #include <deque>
   #include <memory>
   #include <stdexcept>
   #include <string>
   #include <vector>
   
   #include "exceptions.hpp"
   
   namespace util {
   // clang-format off
   #define BYTE_TO_BINARY_PATTERN "%c%c%c%c%c%c%c%c"
   #define BYTE_TO_BINARY(byte) \
     (byte & 0x80 ? '1' : '0'), \
     (byte & 0x40 ? '1' : '0'), \
     (byte & 0x20 ? '1' : '0'), \
     (byte & 0x10 ? '1' : '0'), \
     (byte & 0x08 ? '1' : '0'), \
     (byte & 0x04 ? '1' : '0'), \
     (byte & 0x02 ? '1' : '0'), \
     (byte & 0x01 ? '1' : '0')
   // clang-format on
   
   template <typename T>
   inline T pop_front(std::deque<T>& queue)
   {
     // Get front byte value and then remove it from queue
     auto byte = queue.front();
     queue.pop_front();
   
     return byte;
   }
   
   template <typename T>
   inline std::vector<T> drain_deque(std::deque<T>& queue, size_t n)
   {
     // Store values that have been "popped"
     std::vector<T> retVals{ queue.begin(), queue.begin() + n };
   
     // Remove values from queue
     queue.erase(queue.begin(), queue.begin() + n);
   
     return retVals;
   }
   
   constexpr inline uint32_t uint32FromBEBytes(uint8_t bytes[4])
   {
     return static_cast<uint32_t>(bytes[0] << 24 | bytes[1] << 16 | bytes[2] << 8 | bytes[3] << 0);
   }
   
   template <typename T>
   void assertHasValues(std::deque<T> queue, size_t n, std::string item)
   {
     if (queue.size() < n) {
       throw NDEFException("Too few elements in queue for " + item + " field: " + "require " + std::to_string(n) +
                           " have " + std::to_string(queue.size()));
     }
   
     // Number of elements >= n, no exception tossing today boys
     return;
   }
   
   template <typename T>
   void assertHasValue(std::deque<T> queue, std::string item)
   {
     // That's all we need to know
     if (queue.size() > 0)
       return;
   
     // Oh brother, there are 0 elements in the queue...
     throw NDEFException("Too few elements in queue for " + item + " field: require 1 have 0");
   }
   } // namespace util
   
   #endif // UTIL_H