//
// Copyright (c) 2016-2019 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/beast
//

// Test that header file is self-contained.
#include <boost/beast/http/basic_parser.hpp>

#include "message_fuzz.hpp"
#include "test_parser.hpp"

#include <boost/beast/core/buffer_traits.hpp>
#include <boost/beast/core/buffers_cat.hpp>
#include <boost/beast/core/buffers_prefix.hpp>
#include <boost/beast/core/buffers_suffix.hpp>
#include <boost/beast/core/flat_buffer.hpp>
#include <boost/beast/core/multi_buffer.hpp>
#include <boost/beast/core/ostream.hpp>
#include <boost/beast/http/parser.hpp>
#include <boost/beast/http/string_body.hpp>
#include <boost/beast/test/fuzz.hpp>
#include <boost/beast/_experimental/unit_test/suite.hpp>

namespace boost {
namespace beast {
namespace http {

class basic_parser_test : public beast::unit_test::suite
{
public:
    enum parse_flag
    {
        chunked               =   1,
        connection_keep_alive =   2,
        connection_close      =   4,
        connection_upgrade    =   8,
        upgrade               =  16,
    };

    class expect_version
    {
        suite& s_;
        int version_;

    public:
        expect_version(suite& s, int version)
            : s_(s)
            , version_(version)
        {
        }

        template<class Parser>
        void
        operator()(Parser const& p) const
        {
            s_.BEAST_EXPECT(p.version == version_);
        }
    };

    class expect_status
    {
        suite& s_;
        int status_;

    public:
        expect_status(suite& s, int status)
            : s_(s)
            , status_(status)
        {
        }

        template<class Parser>
        void
        operator()(Parser const& p) const
        {
            s_.BEAST_EXPECT(p.status == status_);
        }
    };

    class expect_flags
    {
        suite& s_;
        unsigned flags_;

    public:
        expect_flags(suite& s, unsigned flags)
            : s_(s)
            , flags_(flags)
        {
        }

        template<class Parser>
        void
        operator()(Parser const& p) const
        {
            if(flags_ & parse_flag::chunked)
                s_.BEAST_EXPECT(p.chunked());
            if(flags_ & parse_flag::connection_keep_alive)
                s_.BEAST_EXPECT(p.keep_alive());
            if(flags_ & parse_flag::connection_close)
                s_.BEAST_EXPECT(! p.keep_alive());
            if(flags_ & parse_flag::upgrade)
                s_.BEAST_EXPECT(! p.upgrade());
        }
    };

    class expect_keepalive
    {
        suite& s_;
        bool v_;

    public:
        expect_keepalive(suite& s, bool v)
            : s_(s)
            , v_(v)
        {
        }

        template<class Parser>
        void
        operator()(Parser const& p) const
        {
            s_.BEAST_EXPECT(p.keep_alive() == v_);
        }
    };

    class expect_body
    {
        suite& s_;
        std::string const& body_;

    public:
        expect_body(expect_body&&) = default;

        expect_body(suite& s, std::string const& v)
            : s_(s)
            , body_(v)
        {
        }

        template<class Parser>
        void
        operator()(Parser const& p) const
        {
            s_.BEAST_EXPECT(p.body == body_);
        }
    };

    //--------------------------------------------------------------------------

    template<class Parser, class ConstBufferSequence, class Test>
    typename std::enable_if<
        net::is_const_buffer_sequence<ConstBufferSequence>::value>::type
    parsegrind(ConstBufferSequence const& buffers,
        Test const& test, bool skip = false)
    {
        auto const size = buffer_bytes(buffers);
        for(std::size_t i = 1; i < size - 1; ++i)
        {
            Parser p;
            p.eager(true);
            p.skip(skip);
            error_code ec;
            buffers_suffix<ConstBufferSequence> cb{buffers};
            auto n = p.put(buffers_prefix(i, cb), ec);
            if(! BEAST_EXPECTS(! ec ||
                    ec == error::need_more, ec.message()))
                continue;
            if(! BEAST_EXPECT(! p.is_done()))
                continue;
            cb.consume(n);
            n = p.put(cb, ec);
            if(! BEAST_EXPECTS(! ec, ec.message()))
                continue;
            if(! BEAST_EXPECT(n == buffer_bytes(cb)))
                continue;
            if(p.need_eof())
            {
                p.put_eof(ec);
                if(! BEAST_EXPECTS(! ec, ec.message()))
                    continue;
            }
            if(! BEAST_EXPECT(p.is_done()))
                continue;
            test(p);
        }
        for(std::size_t i = 1; i < size - 1; ++i)
        {
            Parser p;
            p.eager(true);
            error_code ec;
            buffers_suffix<ConstBufferSequence> cb{buffers};
            cb.consume(i);
            auto n = p.put(buffers_cat(
                buffers_prefix(i, buffers), cb), ec);
            if(! BEAST_EXPECTS(! ec, ec.message()))
                continue;
            if(! BEAST_EXPECT(n == size))
                continue;
            if(p.need_eof())
            {
                p.put_eof(ec);
                if(! BEAST_EXPECTS(! ec, ec.message()))
                    continue;
            }
            test(p);
        }
    }

    template<class Parser, class Test>
    void
    parsegrind(string_view msg, Test const& test, bool skip = false)
    {
        parsegrind<Parser>(net::const_buffer{
            msg.data(), msg.size()}, test, skip);
    }

    template<class Parser, class ConstBufferSequence>
    typename std::enable_if<
        net::is_const_buffer_sequence<ConstBufferSequence>::value>::type
    parsegrind(ConstBufferSequence const& buffers)
    {
        parsegrind<Parser>(buffers, [](Parser const&){});
    }

    template<class Parser>
    void
    parsegrind(string_view msg)
    {
        parsegrind<Parser>(msg, [](Parser const&){});
    }

    template<class Parser>
    void
    failgrind(string_view msg, error_code const& result)
    {
        for(std::size_t i = 1; i < msg.size() - 1; ++i)
        {
            Parser p;
            p.eager(true);
            error_code ec;
            buffers_suffix<net::const_buffer> cb{
                boost::in_place_init, msg.data(), msg.size()};
            auto n = p.put(buffers_prefix(i, cb), ec);
            if(ec == result)
            {
                pass();
                continue;
            }
            if(! BEAST_EXPECTS(
                ec == error::need_more, ec.message()))
                continue;
            if(! BEAST_EXPECT(! p.is_done()))
                continue;
            cb.consume(n);
            n = p.put(cb, ec);
            if(! ec)
                p.put_eof(ec);
            BEAST_EXPECTS(ec == result, ec.message());
        }
        for(std::size_t i = 1; i < msg.size() - 1; ++i)
        {
            Parser p;
            p.eager(true);
            error_code ec;
            p.put(buffers_cat(
                net::const_buffer{msg.data(), i},
                net::const_buffer{
                    msg.data() + i, msg.size() - i}), ec);
            if(! ec)
                p.put_eof(ec);
            BEAST_EXPECTS(ec == result, ec.message());
        }
    }

    //--------------------------------------------------------------------------

    void
    testFlatten()
    {
        parsegrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "\r\n"
            );
        parsegrind<test_parser<true>>(
            "POST / HTTP/1.1\r\n"
            "Content-Length: 5\r\n"
            "\r\n"
            "*****"
            );
        parsegrind<test_parser<false>>(
            "HTTP/1.1 403 Not Found\r\n"
            "\r\n"
            );
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Content-Length: 5\r\n"
            "\r\n"
            "*****"
            );
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n"
            "5;x\r\n*****\r\n"
            "0\r\nMD5: 0xff30\r\n"
            "\r\n"
            );
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "\r\n"
            "*****"
            );
    }

    void
    testObsFold()
    {
        auto const check =
            [&](std::string const& s, string_view value)
            {
                std::string m =
                    "GET / HTTP/1.1\r\n"
                    "f: " + s + "\r\n"
                    "\r\n";
                parsegrind<request_parser<string_body>>(m,
                    [&](request_parser<string_body> const& p)
                    {
                        BEAST_EXPECT(p.get()["f"] == value);
                    });
            };
        check("x",                      "x");
        check(" x",                     "x");
        check("\tx",                    "x");
        check(" \tx",                   "x");
        check("\t x",                   "x");
        check("x ",                     "x");
        check(" x\t",                   "x");
        check("\tx \t",                 "x");
        check(" \tx\t ",                "x");
        check("\t x  \t  ",             "x");
        check("\r\n x",                 "x");
        check(" \r\n x",                "x");
        check(" \r\n\tx",               "x");
        check(" \r\n\t x",              "x");
        check(" \r\n \tx",              "x");
        check("  \r\n \r\n \r\n x \t",  "x");
        check("xy",                     "xy");
        check("\r\n x",                 "x");
        check("\r\n  x",                "x");
        check("\r\n   xy",              "xy");
        check("\r\n \r\n \r\n x",       "x");
        check("\r\n \r\n  \r\n xy",     "xy");
        check("x\r\n y",                "x y");
        check("x\r\n y\r\n z ",         "x y z");
    }

    // Check that all callbacks are invoked
    void
    testCallbacks()
    {
        parsegrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "\r\n",
            [&](test_parser<true> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 0);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 0);
                BEAST_EXPECT(p.got_on_chunk     == 0);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
        parsegrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "User-Agent: test\r\n"
            "Content-Length: 1\r\n"
            "\r\n"
            "*",
            [&](test_parser<true> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 2);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 1);
                BEAST_EXPECT(p.got_on_chunk     == 0);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
        parsegrind<test_parser<false>>(
            "HTTP/1.1 100 Continue\r\n"
            "\r\n",
            [&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 0);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 0);
                BEAST_EXPECT(p.got_on_chunk     == 0);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Content-Length: 1\r\n"
            "\r\n"
            "*",
            [&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 2);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 1);
                BEAST_EXPECT(p.got_on_chunk     == 0);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n"
            "1\r\n*\r\n"
            "0\r\n\r\n",
            [&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 2);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 1);
                BEAST_EXPECT(p.got_on_chunk     == 2);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n"
            "1;x\r\n*\r\n"
            "0\r\n\r\n",
            [&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.got_on_begin     == 1);
                BEAST_EXPECT(p.got_on_field     == 2);
                BEAST_EXPECT(p.got_on_header    == 1);
                BEAST_EXPECT(p.got_on_body      == 1);
                BEAST_EXPECT(p.got_on_chunk     == 2);
                BEAST_EXPECT(p.got_on_complete  == 1);
            });
    }

    void
    testRequestLine()
    {
        using P = test_parser<true>;

        parsegrind<P>("GET /x HTTP/1.0\r\n\r\n");
        parsegrind<P>("!#$%&'*+-.^_`|~0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz / HTTP/1.0\r\n\r\n");
        parsegrind<P>("GET / HTTP/1.0\r\n\r\n",         expect_version{*this, 10});
        parsegrind<P>("G / HTTP/1.1\r\n\r\n",           expect_version{*this, 11});
        // VFALCO TODO various forms of good request-target (uri)

        failgrind<P>("\tGET / HTTP/1.0\r\n"    "\r\n",  error::bad_method);
        failgrind<P>("GET\x01 / HTTP/1.0\r\n"  "\r\n",  error::bad_method);
        failgrind<P>("GET  / HTTP/1.0\r\n"     "\r\n",  error::bad_target);
        failgrind<P>("GET \x01 HTTP/1.0\r\n"   "\r\n",  error::bad_target);
        failgrind<P>("GET /\x01 HTTP/1.0\r\n"  "\r\n",  error::bad_target);
        // VFALCO TODO various forms of bad request-target (uri)
        failgrind<P>("GET /  HTTP/1.0\r\n"     "\r\n",  error::bad_version);
        failgrind<P>("GET / _TTP/1.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / H_TP/1.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HT_P/1.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTT_/1.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP_1.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/01.2\r\n"     "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/3.45\r\n"     "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/67.89\r\n"    "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/x.0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1.x\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1.0 \r\n"     "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1_0\r\n"      "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1.0\n\r\n"    "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1.0\n\r\r\n"  "\r\n",  error::bad_version);
        failgrind<P>("GET / HTTP/1.0\r\r\n"    "\r\n",  error::bad_version);
    }

    void
    testStatusLine()
    {
        using P = test_parser<false>;

        parsegrind<P>("HTTP/1.0 000 OK\r\n"   "\r\n",   expect_status{*this, 0});
        parsegrind<P>("HTTP/1.1 012 OK\r\n"   "\r\n",   expect_status{*this, 12});
        parsegrind<P>("HTTP/1.0 345 OK\r\n"   "\r\n",   expect_status{*this, 345});
        parsegrind<P>("HTTP/1.0 678 OK\r\n"   "\r\n",   expect_status{*this, 678});
        parsegrind<P>("HTTP/1.0 999 OK\r\n"   "\r\n",   expect_status{*this, 999});
        parsegrind<P>("HTTP/1.0 200 \tX\r\n"  "\r\n",   expect_version{*this, 10});
        parsegrind<P>("HTTP/1.1 200  X\r\n"   "\r\n",   expect_version{*this, 11});
        parsegrind<P>("HTTP/1.0 200 \r\n"     "\r\n");
        parsegrind<P>("HTTP/1.1 200 X \r\n"   "\r\n");
        parsegrind<P>("HTTP/1.1 200 X\t\r\n"  "\r\n");
        parsegrind<P>("HTTP/1.1 200 \x80\x81...\xfe\xff\r\n\r\n");
        parsegrind<P>("HTTP/1.1 200 !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\r\n\r\n");

        failgrind<P>("\rHTTP/1.0 200 OK\r\n"  "\r\n",   error::bad_version);
        failgrind<P>("\nHTTP/1.0 200 OK\r\n"  "\r\n",   error::bad_version);
        failgrind<P>(" HTTP/1.0 200 OK\r\n"   "\r\n",   error::bad_version);
        failgrind<P>("_TTP/1.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("H_TP/1.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HT_P/1.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTT_/1.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTTP_1.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTTP/01.2 200 OK\r\n"   "\r\n",   error::bad_version);
        failgrind<P>("HTTP/3.45 200 OK\r\n"   "\r\n",   error::bad_version);
        failgrind<P>("HTTP/67.89 200 OK\r\n"  "\r\n",   error::bad_version);
        failgrind<P>("HTTP/x.0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTTP/1.x 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTTP/1_0 200 OK\r\n"    "\r\n",   error::bad_version);
        failgrind<P>("HTTP/1.0  200 OK\r\n"   "\r\n",   error::bad_status);
        failgrind<P>("HTTP/1.0 0 OK\r\n"      "\r\n",   error::bad_status);
        failgrind<P>("HTTP/1.0 12 OK\r\n"     "\r\n",   error::bad_status);
        failgrind<P>("HTTP/1.0 3456 OK\r\n"   "\r\n",   error::bad_status);
        failgrind<P>("HTTP/1.0 200\r\n"       "\r\n",   error::bad_status);
        failgrind<P>("HTTP/1.0 200 \n\r\n"    "\r\n",   error::bad_reason);
        failgrind<P>("HTTP/1.0 200 \x01\r\n"  "\r\n",   error::bad_reason);
        failgrind<P>("HTTP/1.0 200 \x7f\r\n"  "\r\n",   error::bad_reason);
        failgrind<P>("HTTP/1.0 200 OK\n\r\n"  "\r\n",   error::bad_reason);
        failgrind<P>("HTTP/1.0 200 OK\r\r\n"  "\r\n",   error::bad_line_ending);
    }

    void
    testFields()
    {
        auto const m =
            [](std::string const& s)
            {
                return "GET / HTTP/1.1\r\n" + s + "\r\n";
            };

        using P = test_parser<true>;

        parsegrind<P>(m("f:\r\n"));
        parsegrind<P>(m("f: \r\n"));
        parsegrind<P>(m("f:\t\r\n"));
        parsegrind<P>(m("f: \t\r\n"));
        parsegrind<P>(m("f: v\r\n"));
        parsegrind<P>(m("f:\tv\r\n"));
        parsegrind<P>(m("f:\tv \r\n"));
        parsegrind<P>(m("f:\tv\t\r\n"));
        parsegrind<P>(m("f:\tv\t \r\n"));
        parsegrind<P>(m("f:\r\n \r\n"));
        parsegrind<P>(m("f:v\r\n"));
        parsegrind<P>(m("f: v\r\n u\r\n"));
        parsegrind<P>(m("!#$%&'*+-.^_`|~0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz: v\r\n"));
        parsegrind<P>(m("f: !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\x80\x81...\xfe\xff\r\n"));

        failgrind<P>(m(" f: v\r\n"),        error::bad_field);
        failgrind<P>(m("\tf: v\r\n"),       error::bad_field);
        failgrind<P>(m("f : v\r\n"),        error::bad_field);
        failgrind<P>(m("f\t: v\r\n"),       error::bad_field);
        failgrind<P>(m("f: \n\r\n"),        error::bad_value);
        failgrind<P>(m("f: v\r \r\n"),      error::bad_line_ending);
        failgrind<P>(m("f: \r v\r\n"),      error::bad_line_ending);
        failgrind<P>(
            "GET / HTTP/1.1\r\n"
            "\r \n\r\n"
            "\r\n",                         error::bad_line_ending);
    }

    void
    testConnectionField()
    {
        auto const m = [](std::string const& s)
            { return "GET / HTTP/1.1\r\n" + s + "\r\n"; };
        auto const cn = [](std::string const& s)
            { return "GET / HTTP/1.1\r\nConnection: " + s + "\r\n"; };
    #if 0
        auto const keepalive = [&](bool v)
            { //return keepalive_f{*this, v}; return true; };
    #endif

        using P = test_parser<true>;

        parsegrind<P>(cn("close\r\n"),                         expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn(",close\r\n"),                        expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn(" close\r\n"),                        expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("\tclose\r\n"),                       expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close,\r\n"),                        expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close\t\r\n"),                       expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close\r\n"),                         expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn(" ,\t,,close,, ,\t,,\r\n"),           expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("\r\n close\r\n"),                    expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close\r\n \r\n"),                    expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("any,close\r\n"),                     expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close,any\r\n"),                     expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("any\r\n ,close\r\n"),                expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close\r\n ,any\r\n"),                expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(cn("close,close\r\n"),                   expect_flags{*this, parse_flag::connection_close}); // weird but allowed

        parsegrind<P>(cn("keep-alive\r\n"),                    expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("keep-alive \r\n"),                   expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("keep-alive\t \r\n"),                 expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("keep-alive\t ,x\r\n"),               expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("\r\n keep-alive \t\r\n"),            expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("keep-alive \r\n \t \r\n"),           expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(cn("keep-alive\r\n \r\n"),               expect_flags{*this, parse_flag::connection_keep_alive});

        parsegrind<P>(cn("upgrade\r\n"),                       expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("upgrade \r\n"),                      expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("upgrade\t \r\n"),                    expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("upgrade\t ,x\r\n"),                  expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("\r\n upgrade \t\r\n"),               expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("upgrade \r\n \t \r\n"),              expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(cn("upgrade\r\n \r\n"),                  expect_flags{*this, parse_flag::connection_upgrade});

        // VFALCO What's up with these?
        //parsegrind<P>(cn("close,keep-alive\r\n"),              expect_flags{*this, parse_flag::connection_close | parse_flag::connection_keep_alive});
        parsegrind<P>(cn("upgrade,keep-alive\r\n"),            expect_flags{*this, parse_flag::connection_upgrade | parse_flag::connection_keep_alive});
        parsegrind<P>(cn("upgrade,\r\n keep-alive\r\n"),       expect_flags{*this, parse_flag::connection_upgrade | parse_flag::connection_keep_alive});
        //parsegrind<P>(cn("close,keep-alive,upgrade\r\n"),      expect_flags{*this, parse_flag::connection_close | parse_flag::connection_keep_alive | parse_flag::connection_upgrade});

        parsegrind<P>("GET / HTTP/1.1\r\n\r\n",                expect_keepalive(*this, true));
        parsegrind<P>("GET / HTTP/1.0\r\n\r\n",                expect_keepalive(*this, false));
        parsegrind<P>("GET / HTTP/1.0\r\n"
                   "Connection: keep-alive\r\n\r\n",        expect_keepalive(*this, true));
        parsegrind<P>("GET / HTTP/1.1\r\n"
                   "Connection: close\r\n\r\n",             expect_keepalive(*this, false));

        parsegrind<P>(cn("x\r\n"),                             expect_flags{*this, 0});
        parsegrind<P>(cn("x,y\r\n"),                           expect_flags{*this, 0});
        parsegrind<P>(cn("x ,y\r\n"),                          expect_flags{*this, 0});
        parsegrind<P>(cn("x\t,y\r\n"),                         expect_flags{*this, 0});
        parsegrind<P>(cn("keep\r\n"),                          expect_flags{*this, 0});
        parsegrind<P>(cn(",keep\r\n"),                         expect_flags{*this, 0});
        parsegrind<P>(cn(" keep\r\n"),                         expect_flags{*this, 0});
        parsegrind<P>(cn("\tnone\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(cn("keep,\r\n"),                         expect_flags{*this, 0});
        parsegrind<P>(cn("keep\t\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(cn("keep\r\n"),                          expect_flags{*this, 0});
        parsegrind<P>(cn(" ,\t,,keep,, ,\t,,\r\n"),            expect_flags{*this, 0});
        parsegrind<P>(cn("\r\n keep\r\n"),                     expect_flags{*this, 0});
        parsegrind<P>(cn("keep\r\n \r\n"),                     expect_flags{*this, 0});
        parsegrind<P>(cn("closet\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(cn(",closet\r\n"),                       expect_flags{*this, 0});
        parsegrind<P>(cn(" closet\r\n"),                       expect_flags{*this, 0});
        parsegrind<P>(cn("\tcloset\r\n"),                      expect_flags{*this, 0});
        parsegrind<P>(cn("closet,\r\n"),                       expect_flags{*this, 0});
        parsegrind<P>(cn("closet\t\r\n"),                      expect_flags{*this, 0});
        parsegrind<P>(cn("closet\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(cn(" ,\t,,closet,, ,\t,,\r\n"),          expect_flags{*this, 0});
        parsegrind<P>(cn("\r\n closet\r\n"),                   expect_flags{*this, 0});
        parsegrind<P>(cn("closet\r\n \r\n"),                   expect_flags{*this, 0});
        parsegrind<P>(cn("clog\r\n"),                          expect_flags{*this, 0});
        parsegrind<P>(cn("key\r\n"),                           expect_flags{*this, 0});
        parsegrind<P>(cn("uptown\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(cn("keeper\r\n \r\n"),                   expect_flags{*this, 0});
        parsegrind<P>(cn("keep-alively\r\n \r\n"),             expect_flags{*this, 0});
        parsegrind<P>(cn("up\r\n \r\n"),                       expect_flags{*this, 0});
        parsegrind<P>(cn("upgrader\r\n \r\n"),                 expect_flags{*this, 0});
        parsegrind<P>(cn("none\r\n"),                          expect_flags{*this, 0});
        parsegrind<P>(cn("\r\n none\r\n"),                     expect_flags{*this, 0});

        parsegrind<P>(m("ConnectioX: close\r\n"),              expect_flags{*this, 0});
        parsegrind<P>(m("Condor: close\r\n"),                  expect_flags{*this, 0});
        parsegrind<P>(m("Connect: close\r\n"),                 expect_flags{*this, 0});
        parsegrind<P>(m("Connections: close\r\n"),             expect_flags{*this, 0});

        parsegrind<P>(m("Proxy-Connection: close\r\n"),        expect_flags{*this, parse_flag::connection_close});
        parsegrind<P>(m("Proxy-Connection: keep-alive\r\n"),   expect_flags{*this, parse_flag::connection_keep_alive});
        parsegrind<P>(m("Proxy-Connection: upgrade\r\n"),      expect_flags{*this, parse_flag::connection_upgrade});
        parsegrind<P>(m("Proxy-ConnectioX: none\r\n"),         expect_flags{*this, 0});
        parsegrind<P>(m("Proxy-Connections: 1\r\n"),           expect_flags{*this, 0});
        parsegrind<P>(m("Proxy-Connotes: see-also\r\n"),       expect_flags{*this, 0});

        failgrind<P>(cn("[\r\n"),                              error::bad_value);
        failgrind<P>(cn("close[\r\n"),                         error::bad_value);
        failgrind<P>(cn("close [\r\n"),                        error::bad_value);
        failgrind<P>(cn("close, upgrade [\r\n"),               error::bad_value);
        failgrind<P>(cn("upgrade[]\r\n"),                      error::bad_value);
        failgrind<P>(cn("keep\r\n -alive\r\n"),                error::bad_value);
        failgrind<P>(cn("keep-alive[\r\n"),                    error::bad_value);
        failgrind<P>(cn("keep-alive []\r\n"),                  error::bad_value);
        failgrind<P>(cn("no[ne]\r\n"),                         error::bad_value);
    }

    void
    testContentLengthField()
    {
        using P = test_parser<true>;
        auto const c = [](std::string const& s)
            { return "GET / HTTP/1.1\r\nContent-Length: " + s + "\r\n"; };
        auto const m = [](std::string const& s)
            { return "GET / HTTP/1.1\r\n" + s + "\r\n"; };
        auto const check =
            [&](std::string const& s, std::uint64_t v)
            {
                parsegrind<P>(c(s),
                    [&](P const& p)
                    {
                        BEAST_EXPECT(p.content_length());
                        BEAST_EXPECT(p.content_length() && *p.content_length() == v);
                    }, true);
            };

        check("0\r\n",          0);
        check("00\r\n",         0);
        check("1\r\n",          1);
        check("01\r\n",         1);
        check("9\r\n",          9);
        check("42 \r\n",        42);
        check("42\t\r\n",       42);
        check("42 \t \r\n",     42);
        check("42\r\n \t \r\n", 42);

        parsegrind<P>(m("Content-LengtX: 0\r\n"),           expect_flags{*this, 0});
        parsegrind<P>(m("Content-Lengths: many\r\n"),       expect_flags{*this, 0});
        parsegrind<P>(m("Content: full\r\n"),               expect_flags{*this, 0});
        parsegrind<P>(m("Content-Length: 0\r\n"
                        "Content-Length: 0\r\n"),           expect_flags{*this, 0});

        failgrind<P>(c("\r\n"),                             error::bad_content_length);
        failgrind<P>(c("18446744073709551616\r\n"),         error::bad_content_length);
        failgrind<P>(c("0 0\r\n"),                          error::bad_content_length);
        failgrind<P>(c("0 1\r\n"),                          error::bad_content_length);
        failgrind<P>(c(",\r\n"),                            error::bad_content_length);
        failgrind<P>(c("0,\r\n"),                           error::bad_content_length);
        failgrind<P>(m("Content-Length: 0\r\n"
                        "Content-Length: 100\r\n"),         error::multiple_content_length);
    }

    void
    testTransferEncodingField()
    {
        auto const m = [](std::string const& s)
            { return "GET / HTTP/1.1\r\n" + s + "\r\n"; };
        auto const ce = [](std::string const& s)
            { return "GET / HTTP/1.1\r\nTransfer-Encoding: " + s + "\r\n0\r\n\r\n"; };
        auto const te = [](std::string const& s)
            { return "GET / HTTP/1.1\r\nTransfer-Encoding: " + s + "\r\n"; };

        using P = test_parser<true>;

        parsegrind<P>(ce("chunked\r\n"),                expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked \r\n"),               expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked\t\r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked \t\r\n"),             expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(" chunked\r\n"),               expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("\tchunked\r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked,\r\n"),               expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked ,\r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked, \r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(",chunked\r\n"),               expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(", chunked\r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(" ,chunked\r\n"),              expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("chunked\r\n \r\n"),           expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("\r\n chunked\r\n"),           expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(",\r\n chunked\r\n"),          expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("\r\n ,chunked\r\n"),          expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce(",\r\n chunked\r\n"),          expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("gzip, chunked\r\n"),          expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("gzip, chunked \r\n"),         expect_flags{*this, parse_flag::chunked});
        parsegrind<P>(ce("gzip, \r\n chunked\r\n"),     expect_flags{*this, parse_flag::chunked});

        // Technically invalid but beyond the parser's scope to detect
        // VFALCO Look into this
        //parsegrind<P>(ce("custom;key=\",chunked\r\n"),  expect_flags{*this, parse_flag::chunked});

        parsegrind<P>(te("gzip\r\n"),                   expect_flags{*this, 0});
        parsegrind<P>(te("chunked, gzip\r\n"),          expect_flags{*this, 0});
        parsegrind<P>(te("chunked\r\n , gzip\r\n"),     expect_flags{*this, 0});
        parsegrind<P>(te("chunked,\r\n gzip\r\n"),      expect_flags{*this, 0});
        parsegrind<P>(te("chunked,\r\n ,gzip\r\n"),     expect_flags{*this, 0});
        parsegrind<P>(te("bigchunked\r\n"),             expect_flags{*this, 0});
        parsegrind<P>(te("chunk\r\n ked\r\n"),          expect_flags{*this, 0});
        parsegrind<P>(te("bar\r\n ley chunked\r\n"),    expect_flags{*this, 0});
        parsegrind<P>(te("barley\r\n chunked\r\n"),     expect_flags{*this, 0});

        parsegrind<P>(m("Transfer-EncodinX: none\r\n"), expect_flags{*this, 0});
        parsegrind<P>(m("Transfer-Encodings: 2\r\n"),   expect_flags{*this, 0});
        parsegrind<P>(m("Transfer-Encoded: false\r\n"), expect_flags{*this, 0});

        failgrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Content-Length: 1\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n",                                     error::bad_transfer_encoding);
    }

    void
    testUpgradeField()
    {
        auto const m = [](std::string const& s)
            { return "GET / HTTP/1.1\r\n" + s + "\r\n"; };

        using P = test_parser<true>;

        parsegrind<P>(m("Upgrade:\r\n"),                       expect_flags{*this, parse_flag::upgrade});
        parsegrind<P>(m("Upgrade: \r\n"),                      expect_flags{*this, parse_flag::upgrade});
        parsegrind<P>(m("Upgrade: yes\r\n"),                   expect_flags{*this, parse_flag::upgrade});

        parsegrind<P>(m("Up: yes\r\n"),                        expect_flags{*this, 0});
        parsegrind<P>(m("UpgradX: none\r\n"),                  expect_flags{*this, 0});
        parsegrind<P>(m("Upgrades: 2\r\n"),                    expect_flags{*this, 0});
        parsegrind<P>(m("Upsample: 4x\r\n"),                   expect_flags{*this, 0});

        parsegrind<P>(
            "GET / HTTP/1.1\r\n"
            "Connection: upgrade\r\n"
            "Upgrade: WebSocket\r\n"
            "\r\n",
            [&](P const& p)
            {
                BEAST_EXPECT(p.upgrade());
            });
    }

    void
    testPartial()
    {
        // Make sure the slow-loris defense works and that
        // we don't get duplicate or missing fields on a split.
        parsegrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "a: 0\r\n"
            "b: 1\r\n"
            "c: 2\r\n"
            "d: 3\r\n"
            "e: 4\r\n"
            "f: 5\r\n"
            "g: 6\r\n"
            "h: 7\r\n"
            "i: 8\r\n"
            "j: 9\r\n"
            "\r\n",
            [&](test_parser<true> const& p)
            {
                BEAST_EXPECT(p.fields.size() == 10);
                BEAST_EXPECT(p.fields.at("a") == "0");
                BEAST_EXPECT(p.fields.at("b") == "1");
                BEAST_EXPECT(p.fields.at("c") == "2");
                BEAST_EXPECT(p.fields.at("d") == "3");
                BEAST_EXPECT(p.fields.at("e") == "4");
                BEAST_EXPECT(p.fields.at("f") == "5");
                BEAST_EXPECT(p.fields.at("g") == "6");
                BEAST_EXPECT(p.fields.at("h") == "7");
                BEAST_EXPECT(p.fields.at("i") == "8");
                BEAST_EXPECT(p.fields.at("j") == "9");
            });
    }

    void
    testLimits()
    {
        {
            multi_buffer b;
            ostream(b) <<
                "POST / HTTP/1.1\r\n"
                "Content-Length: 2\r\n"
                "\r\n"
                "**";
            error_code ec;
            test_parser<true> p;
            p.header_limit(10);
            p.eager(true);
            p.put(b.data(), ec);
            BEAST_EXPECTS(ec == error::header_limit, ec.message());
        }
        {
            multi_buffer b;
            ostream(b) <<
                "POST / HTTP/1.1\r\n";
            error_code ec;
            test_parser<true> p;
            p.header_limit(18);
            p.eager(true);
            b.consume(p.put(b.data(), ec));
            BEAST_EXPECTS(ec == error::need_more, ec.message());
            ostream(b) <<
                "field: value\r\n";
            b.consume(p.put(b.data(), ec));
            BEAST_EXPECT(! p.is_done());
            BEAST_EXPECTS(ec == error::header_limit, ec.message());
        }
        {
            multi_buffer b;
            ostream(b) <<
                "POST / HTTP/1.1\r\n"
                "Transfer-Encoding: chunked\r\n"
                "\r\n"
                "0\r\n";
            error_code ec;
            test_parser<true> p;
            p.header_limit(47);
            p.eager(true);
            b.consume(p.put(b.data(), ec));
            BEAST_EXPECTS(ec == error::need_more, ec.message());
            ostream(b) <<
                "field: value\r\n"
                "\r\n";
            b.consume(p.put(b.data(), ec));
            BEAST_EXPECT(! p.is_done());
            BEAST_EXPECTS(ec == error::header_limit, ec.message());
        }
        {
            multi_buffer b;
            ostream(b) <<
                "POST / HTTP/1.1\r\n"
                "Content-Length: 2\r\n"
                "\r\n"
                "**";
            error_code ec;
            test_parser<true> p;
            p.body_limit(1);
            p.eager(true);
            p.put(b.data(), ec);
            BEAST_EXPECTS(ec == error::body_limit, ec.message());
        }
        {
            multi_buffer b;
            ostream(b) <<
                "HTTP/1.1 200 OK\r\n"
                "\r\n"
                "**";
            error_code ec;
            test_parser<false> p;
            p.body_limit(1);
            p.eager(true);
            p.put(b.data(), ec);
            BEAST_EXPECTS(ec == error::body_limit, ec.message());
        }
        {
            multi_buffer b;
            ostream(b) <<
                "POST / HTTP/1.1\r\n"
                "Transfer-Encoding: chunked\r\n"
                "\r\n"
                "2\r\n"
                "**\r\n"
                "0\r\n\r\n";
            error_code ec;
            test_parser<true> p;
            p.body_limit(1);
            p.eager(true);
            p.put(b.data(), ec);
            BEAST_EXPECTS(ec == error::body_limit, ec.message());
        }
    }

    //--------------------------------------------------------------------------

    static
    net::const_buffer
    buf(string_view s)
    {
        return {s.data(), s.size()};
    }

    template<class ConstBufferSequence, bool isRequest>
    std::size_t
    feed(ConstBufferSequence const& buffers,
        basic_parser<isRequest>& p, error_code& ec)
    {
        p.eager(true);
        return p.put(buffers, ec);
    }

    void
    testBody()
    {
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Transfer-Encoding: chunked\r\n"
            "Content-Type: application/octet-stream\r\n"
            "\r\n"
            "4\r\nabcd\r\n"
            "0\r\n\r\n"
            ,[&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.body == "abcd");
            });
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Expect: Expires, MD5-Fingerprint\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n"
            "5\r\n"
            "*****\r\n"
            "2;a;b=1;c=\"2\"\r\n"
            "--\r\n"
            "0;d;e=3;f=\"4\"\r\n"
            "Expires: never\r\n"
            "MD5-Fingerprint: -\r\n"
            "\r\n"
            ,[&](test_parser<false> const& p)
            {
                BEAST_EXPECT(p.body == "*****--");
            });

        parsegrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "Content-Length: 1\r\n"
            "\r\n"
            "1",
            expect_body(*this, "1"));

        parsegrind<test_parser<false>>(
            "HTTP/1.0 200 OK\r\n"
            "\r\n"
            "hello",
            expect_body(*this, "hello"));

        parsegrind<test_parser<true>>(buffers_cat(
            buf("GET / HTTP/1.1\r\n"
                "Content-Length: 10\r\n"
                "\r\n"),
            buf("12"),
            buf("345"),
            buf("67890")));

        // request without Content-Length or
        // Transfer-Encoding: chunked has no body.
        {
            error_code ec;
            test_parser<true> p;
            feed(buf(
                "GET / HTTP/1.0\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }
        {
            error_code ec;
            test_parser<true> p;
            feed(buf(
                "GET / HTTP/1.1\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }

        // response without Content-Length or
        // Transfer-Encoding: chunked requires eof.
        {
            error_code ec;
            test_parser<false> p;
            feed(buf(
                "HTTP/1.0 200 OK\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(! p.is_done());
            BEAST_EXPECT(p.need_eof());
        }

        // 304 "Not Modified" response does not require eof
        {
            error_code ec;
            test_parser<false> p;
            feed(buf(
                "HTTP/1.0 304 Not Modified\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }

        // Chunked response does not require eof
        {
            error_code ec;
            test_parser<false> p;
            feed(buf(
                "HTTP/1.1 200 OK\r\n"
                "Transfer-Encoding: chunked\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(! p.is_done());
            feed(buf(
                "0\r\n\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }

        // restart: 1.0 assumes Connection: close
        {
            error_code ec;
            test_parser<true> p;
            feed(buf(
                "GET / HTTP/1.0\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }

        // restart: 1.1 assumes Connection: keep-alive
        {
            error_code ec;
            test_parser<true> p;
            feed(buf(
                "GET / HTTP/1.1\r\n"
                "\r\n"
                ), p, ec);
            BEAST_EXPECTS(! ec, ec.message());
            BEAST_EXPECT(p.is_done());
        }

        failgrind<test_parser<true>>(
            "GET / HTTP/1.1\r\n"
            "Content-Length: 1\r\n"
            "\r\n",
            error::partial_message);
    }

    //--------------------------------------------------------------------------

    // https://github.com/boostorg/beast/issues/430
    void
    testIssue430()
    {
        parsegrind<test_parser<false>>(
            "HTTP/1.1 200 OK\r\n"
            "Transfer-Encoding: chunked\r\n"
            "Content-Type: application/octet-stream\r\n"
            "\r\n"
            "4\r\nabcd\r\n"
            "0\r\n\r\n");
    }

    // https://github.com/boostorg/beast/issues/452
    void
    testIssue452()
    {
        error_code ec;
        test_parser<true> p;
        p.eager(true);
        string_view s =
            "GET / HTTP/1.1\r\n"
            "\r\n"
            "die!";
        p.put(net::buffer(
            s.data(), s.size()), ec);
        if(! BEAST_EXPECTS(! ec, ec.message()))
            return;
        BEAST_EXPECT(p.is_done());
    }

    // https://github.com/boostorg/beast/issues/496
    void
    testIssue496()
    {
        // The bug affected hex parsing with leading zeroes
        using P = test_parser<false>;
        parsegrind<P>(
            "HTTP/1.1 200 OK\r\n"
            "Transfer-Encoding: chunked\r\n"
            "Content-Type: application/octet-stream\r\n"
            "\r\n"
            "0004\r\nabcd\r\n"
            "0\r\n\r\n"
            ,[&](P const& p)
            {
                BEAST_EXPECT(p.body == "abcd");
            });
    }

    // https://github.com/boostorg/beast/issues/692
    void
    testIssue692()
    {
        error_code ec;
        test_parser<false> p;
        p.eager(true);
        string_view s =
            "HTTP/1.1 101 Switching Protocols\r\n"
            "Content-Length: 2147483648\r\n"
            "\r\n";
        p.put(net::buffer(
            s.data(), s.size()), ec);
        if(! BEAST_EXPECTS(! ec, ec.message()))
            return;
        BEAST_EXPECT(p.is_done());
    }

    //--------------------------------------------------------------------------

    void
    testFuzz()
    {
        auto const grind =
        [&](string_view s)
        {
            static_string<100> ss(s.data(), s.size());
            test::fuzz_rand r;
            test::fuzz(ss, 4, 5, r,
            [&](string_view s)
            {
                error_code ec;
                test_parser<false> p;
                p.eager(true);
                p.put(net::const_buffer{
                    s.data(), s.size()}, ec);
            });
        };
        auto const good =
        [&](string_view s)
        {
            std::string msg =
                "HTTP/1.1 200 OK\r\n"
                "Transfer-Encoding: chunked\r\n"
                "\r\n"
                "0" + std::string(s) + "\r\n"
                "\r\n";
            error_code ec;
            test_parser<false> p;
            p.eager(true);
            p.put(net::const_buffer{
                msg.data(), msg.size()}, ec);
            BEAST_EXPECTS(! ec, ec.message());
            grind(msg);
        };
        auto const bad =
        [&](string_view s)
        {
            std::string msg =
                "HTTP/1.1 200 OK\r\n"
                "Transfer-Encoding: chunked\r\n"
                "\r\n"
                "0" + std::string(s) + "\r\n"
                "\r\n";
            error_code ec;
            test_parser<false> p;
            p.eager(true);
            p.put(net::const_buffer{
                msg.data(), msg.size()}, ec);
            BEAST_EXPECT(ec);
            grind(msg);
        };
        chunkExtensionsTest(good, bad);
    }

    //--------------------------------------------------------------------------

    void
    testRegression1()
    {
        // crash_00cda0b02d5166bd1039ddb3b12618cd80da75f3
        unsigned char buf[] ={
	        0x4C,0x4F,0x43,0x4B,0x20,0x2F,0x25,0x65,0x37,0x6C,0x59,0x3B,0x2F,0x3B,0x3B,0x25,0x30,0x62,0x38,0x3D,0x70,0x2F,0x72,0x20,
	        0x48,0x54,0x54,0x50,0x2F,0x31,0x2E,0x31,0x0D,0x0A,0x41,0x63,0x63,0x65,0x70,0x74,0x2D,0x45,0x6E,0x63,0x6F,0x64,0x69,0x6E,
	        0x67,0x3A,0x0D,0x0A,0x09,0x20,0xEE,0x0D,0x0A,0x4F,0x72,0x69,0x67,0x69,0x6E,0x61,0x6C,0x2D,0x4D,0x65,0x73,0x73,0x61,0x67,
	        0x65,0x2D,0x49,0x44,0x3A,0xEB,0x09,0x09,0x09,0x09,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x3A,0x20,0x0D,0x0A,0x09,0x20,
	        0xF7,0x44,0x9B,0xA5,0x06,0x9F,0x0D,0x0A,0x52,0x65,0x73,0x65,0x6E,0x74,0x2D,0x44,0x61,0x74,0x65,0x3A,0xF4,0x0D,0x0A,0x41,
	        0x6C,0x74,0x2D,0x53,0x76,0x63,0x3A,0x20,0x0D,0x0A,0x54,0x72,0x61,0x69,0x6C,0x65,0x72,0x3A,0x20,0x20,0x09,0x20,0x20,0x20,
	        0x0D,0x0A,0x4C,0x69,0x73,0x74,0x2D,0x49,0x44,0x3A,0xA6,0x6B,0x86,0x09,0x09,0x20,0x09,0x0D,0x0A,0x41,0x6C,0x74,0x65,0x72,
	        0x6E,0x61,0x74,0x65,0x2D,0x52,0x65,0x63,0x69,0x70,0x69,0x65,0x6E,0x74,0x3A,0xF3,0x13,0xE3,0x22,0x9D,0xEF,0xFB,0x84,0x71,
	        0x4A,0xCC,0xBC,0x96,0xF7,0x5B,0x72,0xF1,0xF2,0x0D,0x0A,0x4C,0x6F,0x63,0x61,0x74,0x69,0x6F,0x6E,0x3A,0x20,0x0D,0x0A,0x41,
	        0x63,0x63,0x65,0x70,0x74,0x2D,0x41,0x64,0x64,0x69,0x74,0x69,0x6F,0x6E,0x73,0x3A,0x20,0x0D,0x0A,0x4D,0x4D,0x48,0x53,0x2D,
	        0x4F,0x72,0x69,0x67,0x69,0x6E,0x61,0x74,0x6F,0x72,0x2D,0x50,0x4C,0x41,0x44,0x3A,0x20,0x0D,0x0A,0x4F,0x72,0x69,0x67,0x69,
	        0x6E,0x61,0x6C,0x2D,0x53,0x65,0x6E,0x64,0x65,0x72,0x3A,0x20,0x0D,0x0A,0x4F,0x72,0x69,0x67,0x69,0x6E,0x61,0x6C,0x2D,0x53,
	        0x65,0x6E,0x64,0x65,0x72,0x3A,0x0D,0x0A,0x50,0x49,0x43,0x53,0x2D,0x4C,0x61,0x62,0x65,0x6C,0x3A,0x0D,0x0A,0x20,0x09,0x0D,
	        0x0A,0x49,0x66,0x3A,0x20,0x40,0xC1,0x50,0x5C,0xD6,0xC3,0x86,0xFC,0x8D,0x5C,0x7C,0x96,0x45,0x0D,0x0A,0x4D,0x4D,0x48,0x53,
	        0x2D,0x45,0x78,0x65,0x6D,0x70,0x74,0x65,0x64,0x2D,0x41,0x64,0x64,0x72,0x65,0x73,0x73,0x3A,0x0D,0x0A,0x49,0x6E,0x6A,0x65,
	        0x63,0x74,0x69,0x6F,0x6E,0x2D,0x49,0x6E,0x66,0x6F,0x3A,0x20,0x0D,0x0A,0x43,0x6F,0x6E,0x74,0x65,0x74,0x6E,0x2D,0x4C,0x65,
            0x6E,0x67,0x74,0x68,0x3A,0x20,0x30,0x0D,0x0A,0x0D,0x0A
        };

        error_code ec;
        test_parser<true> p;
        feed(net::buffer(buf, sizeof(buf)), p, ec);
        BEAST_EXPECT(ec);
    }

    void
    testIssue1211()
    {
        using base = detail::basic_parser_base;
        auto const good =
            [&](string_view s, std::uint32_t v0)
            {
                std::uint64_t v;
                auto const result =
                    base::parse_dec(s, v);
                if(BEAST_EXPECTS(result, s))
                    BEAST_EXPECTS(v == v0, s);
            };
        auto const bad =
            [&](string_view s)
            {
                std::uint64_t v;
                auto const result =
                    base::parse_dec(s, v);
                BEAST_EXPECTS(! result, s);
            };
        good("0",           0);
        good("00",          0);
        good("001",         1);
        good("255",         255);
        good("65535",       65535);
        good("65536",       65536);
        good("4294967295",  4294967295);
        bad ("");
        bad (" ");
        bad (" 0");
        bad ("0 ");
        bad ("-1");
        bad ("18446744073709551616"); // max(uint64) + 1
    }

    void
    testIssue1267()
    {
        using base = detail::basic_parser_base;
        auto const good =
            [&](string_view s, std::uint64_t v0)
            {
                std::uint64_t v;
                auto it = s.data();
                auto const result =
                    base::parse_hex(it, v);
                if(BEAST_EXPECTS(result, s))
                    BEAST_EXPECTS(v == v0, s);
            };
        auto const bad =
            [&](string_view s)
            {
                std::uint64_t v;
                auto it = s.data();
                auto const result =
                    base::parse_hex(it, v);
                BEAST_EXPECTS(! result, s);
            };
        good("f\r\n",               15);
        good("ff\r\n",              255);
        good("ffff\r\n",            65535);
        good("ffffffffr\n",         4294967295);
        good("ffffffffffffffff\r\n", 18446744073709551615ULL);
        bad ("\r\n");
        bad ("g\r\n");
        bad ("10000000000000000\r\n");
        bad ("ffffffffffffffffffffff\r\n");
    }

    //--------------------------------------------------------------------------

    // https://github.com/boostorg/beast/issues/1734

    void
    testIssue1734()
    {
        // Ensure more than one buffer, this is to avoid an optimized path in
        // basic_parser::put(ConstBufferSequence const&,...) which avoids
        // buffer flattening.
        auto multibufs = [](multi_buffer::const_buffers_type buffers) {
            std::vector<net::const_buffer> bs;
            for (auto b : buffers_range(buffers))
                bs.push_back(b);
            while (std::distance(bs.begin(), bs.end()) < 2) {
                bs.push_back({});
            }
            return bs;
        };

        // Buffers must be bigger than max_stack_buffer to force flattening
        // in basic_parser::put(ConstBufferSequence const&,...)
        std::string first_chunk_data(
            2 * basic_parser<false>::max_stack_buffer + 1, 'x');

        std::string second_chunk_data_part1(
            basic_parser<false>::max_stack_buffer + 2, 'x');
        std::string second_chunk_data_part2(
            basic_parser<false>::max_stack_buffer + 1, 'x');

        multi_buffer b;
        parser<false, string_body> p;
        p.eager(true);
        error_code ec;
        std::size_t used;

        ostream(b) <<
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n";

        used = p.put(b.data(), ec);
        b.consume(used);

        BEAST_EXPECT(net::buffer_size(b.data()) == 0);
        BEAST_EXPECTS(!ec, ec.message());
        BEAST_EXPECT(!p.is_done());
        BEAST_EXPECT(p.is_header_done());

        ostream(b) <<
            std::hex <<
            first_chunk_data.size() << "\r\n" <<
            first_chunk_data << "\r\n";

        // First chunk
        used = p.put(multibufs(b.data()), ec);
        b.consume(used);

        BEAST_EXPECTS(ec == error::need_more, ec.message());
        BEAST_EXPECT(!p.is_done());

        ostream(b) <<
            std::hex <<
            (second_chunk_data_part1.size() +
             second_chunk_data_part2.size() ) << "\r\n" <<
            second_chunk_data_part1;

        // Second chunk, part 1
        used = p.put(multibufs(b.data()), ec);
        b.consume(used);

        BEAST_EXPECTS(!ec, ec.message());
        BEAST_EXPECT(!p.is_done());

        ostream(b) <<
            second_chunk_data_part2 << "\r\n"
            << "0\r\n\r\n";

        // Second chunk, part 2
        used = p.put(multibufs(b.data()), ec);
        b.consume(used);

        BEAST_EXPECTS(!ec, ec.message()); // <-- Error: bad chunk
        if(p.need_eof())
        {
            p.put_eof(ec);
            BEAST_EXPECTS(! ec, ec.message());
        }
        BEAST_EXPECT(p.is_done());
    }

    void
    testChunkedOverflow()
    {
        {
            const std::string hdr =
                "HTTP/1.1 200 OK" "\r\n"
                "Server: test" "\r\n"
                "Transfer-Encoding: chunked" "\r\n"
                "\r\n";
            const std::string chunk1 =
                "10000000000000000" "\r\n"
                "data...";
            test_parser<false> p;
            error_code ec;
            p.put(net::buffer(hdr), ec);
            BEAST_EXPECT(!ec);
            BEAST_EXPECT(p.is_header_done());
            auto bt = p.put(net::buffer(chunk1), ec);
            BEAST_EXPECT(bt == 0);
            BEAST_EXPECT(ec == error::bad_chunk);
        }
        {
            const std::string hdr =
                "HTTP/1.1 200 OK" "\r\n"
                "Server: test" "\r\n"
                "Transfer-Encoding: chunked" "\r\n"
                "\r\n"
                "1" "\r\n"
                "x" "\r\n";
            const std::string chunk2 =
                "FFFFFFFFFFFFFFFF" "\r\n"
                "data...";
            test_parser<false> p;
            p.eager(true);
            error_code ec;
            flat_buffer fb;
            fb.commit(net::buffer_copy(fb.prepare(10000), net::buffer(hdr)));
            fb.consume(p.put(fb.data(), ec));
            BEAST_EXPECT(p.is_header_done());
            BEAST_EXPECT(ec = error::need_more);
            fb.commit(net::buffer_copy(fb.prepare(10000), net::buffer(chunk2)));
            auto bt = p.put(fb.data(), ec);
            BEAST_EXPECT(bt == 0);
            BEAST_EXPECT(ec == error::body_limit);
        }
        {
            const std::string hdr =
                "HTTP/1.1 200 OK" "\r\n"
                "Server: test" "\r\n"
                "Transfer-Encoding: chunked" "\r\n"
                "\r\n"
                "1" "\r\n"
                "x" "\r\n";
            const std::string chunk2 =
                "FFFFFFFFFFFFFFFF" "\r\n"
                "data...";
            test_parser<false> p;
            p.eager(true);
            p.body_limit(boost::none);
            error_code ec;
            flat_buffer fb;
            fb.commit(net::buffer_copy(fb.prepare(10000), net::buffer(hdr)));
            fb.consume(p.put(fb.data(), ec));
            BEAST_EXPECT(p.is_header_done());
            BEAST_EXPECTS(ec = error::need_more, ec.message());
            fb.commit(net::buffer_copy(fb.prepare(10000), net::buffer(chunk2)));
            auto bt = p.put(fb.data(), ec);
            BEAST_EXPECT(bt == 27);
            BEAST_EXPECT(!ec);
        }
    }

    void testChunkedBodySize()
    {
        string_view resp =
            "HTTP/1.1 200 OK\r\n"
            "Server: test\r\n"
            "Transfer-Encoding: chunked\r\n"
            "\r\n"

            // chunk 1
            "4\r\n"
            "Wiki\r\n"

            // chunk 2
            "5\r\n"
            "pedia\r\n"

            // chunk 3
            "E\r\n"
            " in\r\n"
            "\r\n"
            "chunks.\r\n"

            // end
            "0\r\n"
            "\r\n";

        {  // body limit not exceeded
            test_parser<false> p;
            p.eager(true);
            p.body_limit(23);
            error_code ec;
            p.put(net::buffer(resp.data(), resp.size()), ec);
            BEAST_EXPECT(!ec);
            p.put_eof(ec);
            BEAST_EXPECT(!ec);
        }

        {  // body limit exceeded
            test_parser<false> p;
            p.eager(true);
            p.body_limit(22);
            error_code ec;
            p.put(net::buffer(resp.data(), resp.size()), ec);
            BEAST_EXPECT(ec == error::body_limit);
            p.put_eof(ec);
            BEAST_EXPECT(ec == error::partial_message);
        }
    }

    void
    testUnlimitedBody()
    {
        const char data[] =
            "POST / HTTP/1.1\r\n"
            "Content-Length: 5\r\n"
            "\r\n"
            "*****";

        test::fail_count fc(1000);
        test_parser<true> p(fc);
        p.body_limit(none);
        error_code ec;
        p.put(net::buffer(data, strlen(data)), ec);
        BEAST_EXPECTS(!ec, ec.message());
    }

    void
    testIssue2201()
    {
        const char data[] =
            "HTTP/1.1 200 OK\r\n"
            "Content-Length: 5\r\n"
            "\r\n"
            "*****";

        test_parser<false> p;
        p.eager(true);
        p.body_limit(3);
        error_code ec;
        p.put(net::buffer(data, strlen(data)), ec);
        BEAST_EXPECT(ec == error::body_limit);
    }

    //--------------------------------------------------------------------------

    void
    run() override
    {
        testFlatten();
        testObsFold();
        testCallbacks();
        testRequestLine();
        testStatusLine();
        testFields();
        testConnectionField();
        testContentLengthField();
        testTransferEncodingField();
        testUpgradeField();
        testPartial();
        testLimits();
        testBody();
        testIssue430();
        testIssue452();
        testIssue496();
        testIssue692();
        testFuzz();
        testRegression1();
        testIssue1211();
        testIssue1267();
        testChunkedOverflow();
        testChunkedBodySize();
        testUnlimitedBody();
        testIssue2201();
    }
};

BEAST_DEFINE_TESTSUITE(beast,http,basic_parser);

} // http
} // beast
} // boost
