Added thirdparty: boost library

thirdparty/include/boost/url/grammar/hexdig_chars.hpp

@@ -0,0 +1,158 @@
+//
+// Copyright (c) 2021 Vinnie Falco (vinnie dot falco at gmail 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)
+//
+// Official repository: https://github.com/boostorg/url
+//
+
+#ifndef BOOST_URL_GRAMMAR_HEXDIG_CHARS_HPP
+#define BOOST_URL_GRAMMAR_HEXDIG_CHARS_HPP
+
+#include <boost/url/detail/config.hpp>
+#include <boost/url/grammar/detail/charset.hpp>
+
+namespace boost {
+namespace urls {
+namespace grammar {
+
+/** The set of hexadecimal digits
+
+    @par Example
+    Character sets are used with rules and the
+    functions @ref find_if and @ref find_if_not.
+    @code
+    system::result< core::string_view > rv = parse( "8086FC19", token_rule( hexdig_chars ) );
+    @endcode
+
+    @par BNF
+    @code
+    HEXDIG      = DIGIT
+                / "A" / "B" / "C" / "D" / "E" / "F"
+                / "a" / "b" / "c" / "d" / "e" / "f"
+    @endcode
+
+    @note The RFCs are inconsistent on the case
+    sensitivity of hexadecimal digits. Existing
+    uses suggest case-insensitivity is a de-facto
+    standard.
+
+    @par Specification
+    @li <a href="https://datatracker.ietf.org/doc/html/rfc5234#appendix-B.1"
+        >B.1. Core Rules (rfc5234)</a>
+    @li <a href="https://datatracker.ietf.org/doc/html/rfc7230#section-1.2"
+        >1.2. Syntax Notation (rfc7230)</a>
+    @li <a href="https://datatracker.ietf.org/doc/html/rfc5952#section-2.3"
+        >2.3. Uppercase or Lowercase (rfc5952)</a>
+    @li <a href="https://datatracker.ietf.org/doc/html/rfc5952#section-4.3"
+        >4.3. Lowercase (rfc5952)</a>
+
+    @see
+        @ref find_if,
+        @ref find_if_not,
+        @ref hexdig_value,
+        @ref parse,
+        @ref token_rule.
+*/
+#ifdef BOOST_URL_DOCS
+constexpr __implementation_defined__ hexdig_chars;
+#else
+struct hexdig_chars_t
+{
+    /** Return true if c is in the character set.
+    */
+    constexpr
+    bool
+    operator()(char c) const noexcept
+    {
+        return
+            (c >= '0' && c <= '9') ||
+            (c >= 'A' && c <= 'F') ||
+            (c >= 'a' && c <= 'f');
+    }
+
+#ifdef BOOST_URL_USE_SSE2
+    char const*
+    find_if(
+        char const* first,
+        char const* last) const noexcept
+    {
+        return detail::find_if_pred(
+            *this, first, last);
+    }
+
+    char const*
+    find_if_not(
+        char const* first,
+        char const* last) const noexcept
+    {
+        return detail::find_if_not_pred(
+            *this, first, last);
+    }
+#endif
+};
+
+constexpr hexdig_chars_t hexdig_chars{};
+#endif
+
+// VFALCO We can declare
+// these later if needed
+//
+//struct hexdig_upper_chars;
+//struct hexdig_lower_chars;
+
+/** Return the decimal value of a hex character
+
+    This function returns the decimal
+    value of a hexadecimal character,
+    or -1 if the argument is not a
+    valid hexadecimal digit.
+
+    @par BNF
+    @code
+    HEXDIG      = DIGIT
+                / "A" / "B" / "C" / "D" / "E" / "F"
+                / "a" / "b" / "c" / "d" / "e" / "f"
+    @endcode
+
+    @param ch The character to check
+
+    @return The decimal value or -1
+*/
+inline
+signed char
+hexdig_value(char ch) noexcept
+{
+    // Idea for switch statement to
+    // minimize emitted assembly from
+    // Glen Fernandes
+    signed char res;
+    switch(ch)
+    {
+    default:            res = -1; break;
+    case '0':           res =  0; break;
+    case '1':           res =  1; break;
+    case '2':           res =  2; break;
+    case '3':           res =  3; break;
+    case '4':           res =  4; break;
+    case '5':           res =  5; break;
+    case '6':           res =  6; break;
+    case '7':           res =  7; break;
+    case '8':           res =  8; break;
+    case '9':           res =  9; break;
+    case 'a': case 'A': res = 10; break;
+    case 'b': case 'B': res = 11; break;
+    case 'c': case 'C': res = 12; break;
+    case 'd': case 'D': res = 13; break;
+    case 'e': case 'E': res = 14; break;
+    case 'f': case 'F': res = 15; break;
+    }
+    return res;
+}
+
+} // grammar
+} // urls
+} // boost
+
+#endif