ceph/src/boost/libs/asio/example/cpp03/chat/chat_message.hpp

   1 //
   2 // chat_message.hpp
   3 // ~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #ifndef CHAT_MESSAGE_HPP
  12 #define CHAT_MESSAGE_HPP
  13
  14 #include <cstdio>
  15 #include <cstdlib>
  16 #include <cstring>
  17
  18 class chat_message
  19 {
  20 public:
  21   enum
  22   {
  23     header_length = 4,
  24     max_body_length = 512
  25   };
  26
  27   chat_message()
  28     : body_length_(0)
  29   {
  30   }
  31
  32   const char* data() const
  33   {
  34     return data_;
  35   }
  36
  37   char* data()
  38   {
  39     return data_;
  40   }
  41
  42   size_t length() const
  43   {
  44     return header_length + body_length_;
  45   }
  46
  47   const char* body() const
  48   {
  49     return data_ + header_length;
  50   }
  51
  52   char* body()
  53   {
  54     return data_ + header_length;
  55   }
  56
  57   size_t body_length() const
  58   {
  59     return body_length_;
  60   }
  61
  62   void body_length(size_t new_length)
  63   {
  64     body_length_ = new_length;
  65     if (body_length_ > max_body_length)
  66       body_length_ = max_body_length;
  67   }
  68
  69   bool decode_header()
  70   {
  71     using namespace std; // For strncat and atoi.
  72     char header[header_length + 1] = "";
  73     strncat(header, data_, header_length);
  74     body_length_ = atoi(header);
  75     if (body_length_ > max_body_length)
  76     {
  77       body_length_ = 0;
  78       return false;
  79     }
  80     return true;
  81   }
  82
  83   void encode_header()
  84   {
  85     using namespace std; // For sprintf and memcpy.
  86     char header[header_length + 1] = "";
  87     sprintf(header, "%4d", static_cast<int>(body_length_));
  88     memcpy(data_, header, header_length);
  89   }
  90
  91 private:
  92   char data_[header_length + max_body_length];
  93   size_t body_length_;
  94 };
  95
  96 #endif // CHAT_MESSAGE_HPP