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-rw-r--r--3rdparty/asio/src/examples/cpp03/icmp/icmp_header.hpp94
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diff --git a/3rdparty/asio/src/examples/cpp03/icmp/icmp_header.hpp b/3rdparty/asio/src/examples/cpp03/icmp/icmp_header.hpp
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+++ b/3rdparty/asio/src/examples/cpp03/icmp/icmp_header.hpp
@@ -0,0 +1,94 @@
+//
+// icmp_header.hpp
+// ~~~~~~~~~~~~~~~
+//
+// Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+
+#ifndef ICMP_HEADER_HPP
+#define ICMP_HEADER_HPP
+
+#include <istream>
+#include <ostream>
+#include <algorithm>
+
+// ICMP header for both IPv4 and IPv6.
+//
+// The wire format of an ICMP header is:
+//
+// 0 8 16 31
+// +---------------+---------------+------------------------------+ ---
+// | | | | ^
+// | type | code | checksum | |
+// | | | | |
+// +---------------+---------------+------------------------------+ 8 bytes
+// | | | |
+// | identifier | sequence number | |
+// | | | v
+// +-------------------------------+------------------------------+ ---
+
+class icmp_header
+{
+public:
+ enum { echo_reply = 0, destination_unreachable = 3, source_quench = 4,
+ redirect = 5, echo_request = 8, time_exceeded = 11, parameter_problem = 12,
+ timestamp_request = 13, timestamp_reply = 14, info_request = 15,
+ info_reply = 16, address_request = 17, address_reply = 18 };
+
+ icmp_header() { std::fill(rep_, rep_ + sizeof(rep_), 0); }
+
+ unsigned char type() const { return rep_[0]; }
+ unsigned char code() const { return rep_[1]; }
+ unsigned short checksum() const { return decode(2, 3); }
+ unsigned short identifier() const { return decode(4, 5); }
+ unsigned short sequence_number() const { return decode(6, 7); }
+
+ void type(unsigned char n) { rep_[0] = n; }
+ void code(unsigned char n) { rep_[1] = n; }
+ void checksum(unsigned short n) { encode(2, 3, n); }
+ void identifier(unsigned short n) { encode(4, 5, n); }
+ void sequence_number(unsigned short n) { encode(6, 7, n); }
+
+ friend std::istream& operator>>(std::istream& is, icmp_header& header)
+ { return is.read(reinterpret_cast<char*>(header.rep_), 8); }
+
+ friend std::ostream& operator<<(std::ostream& os, const icmp_header& header)
+ { return os.write(reinterpret_cast<const char*>(header.rep_), 8); }
+
+private:
+ unsigned short decode(int a, int b) const
+ { return (rep_[a] << 8) + rep_[b]; }
+
+ void encode(int a, int b, unsigned short n)
+ {
+ rep_[a] = static_cast<unsigned char>(n >> 8);
+ rep_[b] = static_cast<unsigned char>(n & 0xFF);
+ }
+
+ unsigned char rep_[8];
+};
+
+template <typename Iterator>
+void compute_checksum(icmp_header& header,
+ Iterator body_begin, Iterator body_end)
+{
+ unsigned int sum = (header.type() << 8) + header.code()
+ + header.identifier() + header.sequence_number();
+
+ Iterator body_iter = body_begin;
+ while (body_iter != body_end)
+ {
+ sum += (static_cast<unsigned char>(*body_iter++) << 8);
+ if (body_iter != body_end)
+ sum += static_cast<unsigned char>(*body_iter++);
+ }
+
+ sum = (sum >> 16) + (sum & 0xFFFF);
+ sum += (sum >> 16);
+ header.checksum(static_cast<unsigned short>(~sum));
+}
+
+#endif // ICMP_HEADER_HPP