Added thirdparty: boost library

thirdparty/include/boost/json/detail/buffer.hpp

@@ -0,0 +1,146 @@
+//
+// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.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)
+//
+// Official repository: https://github.com/boostorg/json
+//
+
+#ifndef BOOST_JSON_DETAIL_BUFFER_HPP
+#define BOOST_JSON_DETAIL_BUFFER_HPP
+
+#include <boost/json/detail/config.hpp>
+#include <boost/json/string_view.hpp>
+#include <cstring>
+
+namespace boost {
+namespace json {
+namespace detail {
+
+// A simple string-like temporary static buffer
+template<std::size_t N>
+class buffer
+{
+public:
+    using size_type = std::size_t;
+
+    buffer() = default;
+
+    bool
+    empty() const noexcept
+    {
+        return size_ == 0;
+    }
+
+    string_view
+    get() const noexcept
+    {
+        return {buf_, size_};
+    }
+
+    operator string_view() const noexcept
+    {
+        return get();
+    }
+
+    char const*
+    data() const noexcept
+    {
+        return buf_;
+    }
+
+    size_type
+    size() const noexcept
+    {
+        return size_;
+    }
+
+    size_type
+    capacity() const noexcept
+    {
+        return N - size_;
+    }
+
+    size_type
+    max_size() const noexcept
+    {
+        return N;
+    }
+
+    void
+    clear() noexcept
+    {
+        size_ = 0;
+    }
+
+    void
+    push_back(char ch) noexcept
+    {
+        BOOST_ASSERT(capacity() > 0);
+        buf_[size_++] = ch;
+    }
+
+    // append an unescaped string
+    void
+    append(
+        char const* s,
+        size_type n)
+    {
+        BOOST_ASSERT(n <= N - size_);
+        std::memcpy(buf_ + size_, s, n);
+        size_ += n;
+    }
+
+    // append valid 32-bit code point as utf8
+    void
+    append_utf8(
+        unsigned long cp) noexcept
+    {
+        auto dest = buf_ + size_;
+        if(cp < 0x80)
+        {
+            BOOST_ASSERT(size_ <= N - 1);
+            dest[0] = static_cast<char>(cp);
+            size_ += 1;
+            return;
+        }
+
+        if(cp < 0x800)
+        {
+            BOOST_ASSERT(size_ <= N - 2);
+            dest[0] = static_cast<char>( (cp >> 6)          | 0xc0);
+            dest[1] = static_cast<char>( (cp & 0x3f)        | 0x80);
+            size_ += 2;
+            return;
+        }
+
+        if(cp < 0x10000)
+        {
+            BOOST_ASSERT(size_ <= N - 3);
+            dest[0] = static_cast<char>( (cp >> 12)         | 0xe0);
+            dest[1] = static_cast<char>(((cp >> 6) & 0x3f)  | 0x80);
+            dest[2] = static_cast<char>( (cp       & 0x3f)  | 0x80);
+            size_ += 3;
+            return;
+        }
+
+        {
+            BOOST_ASSERT(size_ <= N - 4);
+            dest[0] = static_cast<char>( (cp >> 18)         | 0xf0);
+            dest[1] = static_cast<char>(((cp >> 12) & 0x3f) | 0x80);
+            dest[2] = static_cast<char>(((cp >> 6)  & 0x3f) | 0x80);
+            dest[3] = static_cast<char>( (cp        & 0x3f) | 0x80);
+            size_ += 4;
+        }
+    }
+private:
+    char buf_[N];
+    size_type size_ = 0;
+};
+
+} // detail
+} // namespace json
+} // namespace boost
+
+#endif