parser is move constructible and move assignable

Author: ashtum

include/boost/http_proto/detail/managed.hpp

@@ -0,0 +1,54 @@
+//
+// Copyright (c) 2025 Mohammad Nejati
+//
+// 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/cppalliance/http_proto
+//
+
+#ifndef BOOST_HTTP_PROTO_DETAIL_MANAGED_HPP
+#define BOOST_HTTP_PROTO_DETAIL_MANAGED_HPP
+
+namespace boost {
+namespace http_proto {
+namespace detail {
+
+template<typename T, T Default>
+class managed
+{
+    T value_ = Default;
+
+public:
+    managed() = default;
+
+    managed(T s) noexcept
+        : value_(s)
+    {
+    }
+
+    managed(managed&& other) noexcept
+        : value_(other.value_)
+    {
+        other.value_ = Default;
+    }
+
+    managed&
+    operator=(managed&& other) noexcept
+    {
+        value_ = other.value_;
+        other.value_ = Default;
+        return *this;
+    }
+
+    operator T() const noexcept
+    {
+        return value_;
+    }
+};
+
+} // detail
+} // http_proto
+} // boost
+
+#endif

include/boost/http_proto/impl/parser.hpp

@@ -21,8 +21,6 @@
 namespace boost {
 namespace http_proto {
 
-//------------------------------------------------
-
 template<class ElasticBuffer>
 typename std::enable_if<
     ! detail::is_reference_wrapper<
@@ -44,21 +42,20 @@ set_body(
         buffers::is_dynamic_buffer<ElasticBuffer>::value,
         "Type requirements not met.");
 
-    // body must not be set already
-    if(how_ != how::in_place)
+    // body must not already be set
+    if(is_body_set())
         detail::throw_logic_error();
 
     // headers must be complete
     if(! got_header())
         detail::throw_logic_error();
 
-    auto& dyn = ws_.emplace<
+    auto& dyn = ws().emplace<
         buffers::any_dynamic_buffer_impl<typename
             std::decay<ElasticBuffer>::type,
                 buffers_N>>(std::forward<ElasticBuffer>(eb));
-    eb_ = &dyn;
-    how_ = how::elastic;
-    on_set_body();
+
+    set_body_impl(dyn);
 }
 
 template<class ElasticBuffer>
@@ -72,24 +69,21 @@ set_body(
         buffers::is_dynamic_buffer<ElasticBuffer>::value,
         "Type requirements not met.");
 
-    // body must not be set already
-    if(how_ != how::in_place)
+    // body must not already be set
+    if(is_body_set())
         detail::throw_logic_error();
 
     // headers must be complete
     if(! got_header())
         detail::throw_logic_error();
 
-    auto& dyn = ws_.emplace<
+    auto& dyn = ws().emplace<
         buffers::any_dynamic_buffer_impl<typename
             std::decay<ElasticBuffer>::type&,
                 buffers_N>>(eb);
-    eb_ = &dyn;
-    how_ = how::elastic;
-    on_set_body();
-}
 
-//------------------------------------------------
+    set_body_impl(dyn);
+}
 
 template<
     class Sink,
@@ -99,19 +93,18 @@ Sink&
 parser::
 set_body(Args&&... args)
 {
-    // body must not be set already
-    if(how_ != how::in_place)
+    // body must not already be set
+    if(is_body_set())
         detail::throw_logic_error();
 
     // headers must be complete
     if(! got_header())
         detail::throw_logic_error();
 
-    auto& s = ws_.emplace<Sink>(
+    auto& s = ws().emplace<Sink>(
         std::forward<Args>(args)...);
-    sink_ = &s;
-    how_ = how::sink;
-    on_set_body();
+
+    set_body_impl(s);
     return s;
 }
 

include/boost/http_proto/parser.hpp

@@ -15,18 +15,14 @@
 #include <boost/http_proto/detail/header.hpp>
 #include <boost/http_proto/detail/type_traits.hpp>
 #include <boost/http_proto/detail/workspace.hpp>
-#include <boost/http_proto/error.hpp>
 #include <boost/http_proto/header_limits.hpp>
 #include <boost/http_proto/sink.hpp>
 
 #include <boost/buffers/any_dynamic_buffer.hpp>
-#include <boost/buffers/circular_buffer.hpp>
-#include <boost/buffers/flat_buffer.hpp>
 #include <boost/buffers/mutable_buffer_pair.hpp>
 #include <boost/buffers/mutable_buffer_span.hpp>
 #include <boost/buffers/type_traits.hpp>
 #include <boost/rts/context_fwd.hpp>
-#include <boost/url/grammar/error.hpp>
 
 #include <cstddef>
 #include <cstdint>
@@ -37,10 +33,6 @@ namespace http_proto {
 // Forward declaration
 class request_parser;
 class response_parser;
-namespace detail {
-class parser_service;
-class filter;
-} // detail
 
 /** A parser for HTTP/1 messages.
 
@@ -92,30 +84,6 @@ class parser
     using const_buffers_type =
         buffers::const_buffer_span;
 
-    //--------------------------------------------
-    //
-    // Special Members
-    //
-    //--------------------------------------------
-
-    /** Constructor (deleted)
-    */
-    // TODO
-    parser(parser&&) = delete;
-
-    /** Assignment (deleted)
-    */
-    // TODO
-    parser& operator=(parser&&) = delete;
-
-    /** Destructor.
-
-        Any views or buffers obtained from this
-        parser become invalid.
-    */
-    BOOST_HTTP_PROTO_DECL
-    ~parser();
-
     //--------------------------------------------
     //
     // Observers
@@ -643,87 +611,47 @@ class parser
 private:
     friend class request_parser;
     friend class response_parser;
+    class impl;
 
     BOOST_HTTP_PROTO_DECL
     parser(
         const rts::context&,
         detail::kind);
 
     BOOST_HTTP_PROTO_DECL
-    void
-    start_impl(bool);
+    parser(parser&& other) noexcept;
 
     BOOST_HTTP_PROTO_DECL
-    void
-    on_set_body() noexcept;
+    parser& operator=(parser&& other) noexcept;
 
-    std::size_t
-    apply_filter(
-        system::error_code&,
-        std::size_t,
-        bool);
+    BOOST_HTTP_PROTO_DECL
+    ~parser();
+
+    BOOST_HTTP_PROTO_DECL
+    void
+    start_impl(bool);
 
     detail::header const*
     safe_get_header() const;
 
+    BOOST_HTTP_PROTO_DECL
+    detail::workspace&
+    ws() noexcept;
+
+    BOOST_HTTP_PROTO_DECL
     bool
-    is_plain() const noexcept;
+    is_body_set() const noexcept;
 
-    std::uint64_t
-    body_limit_remain() const noexcept;
+    BOOST_HTTP_PROTO_DECL
+    void
+    set_body_impl(buffers::any_dynamic_buffer&) noexcept;
 
-    static constexpr unsigned buffers_N = 8;
+    BOOST_HTTP_PROTO_DECL
+    void
+    set_body_impl(sink&) noexcept;
 
-    enum class state
-    {
-        reset,
-        start,
-        header,
-        header_done,
-        body,
-        set_body,
-        complete_in_place,
-        complete
-    };
-
-    enum class how
-    {
-        in_place,
-        sink,
-        elastic,
-    };
-
-    const rts::context& ctx_;
-    detail::parser_service& svc_;
-
-    detail::workspace ws_;
-    detail::header h_;
-    std::uint64_t body_limit_;
-    std::uint64_t body_total_;
-    std::uint64_t payload_remain_;
-    std::uint64_t chunk_remain_;
-    std::size_t body_avail_;
-    std::size_t nprepare_;
-
-    buffers::flat_buffer fb_;
-    buffers::circular_buffer cb0_;
-    buffers::circular_buffer cb1_;
-
-    buffers::mutable_buffer_pair mbp_;
-    buffers::const_buffer_pair cbp_;
-
-    detail::filter* filter_;
-    buffers::any_dynamic_buffer* eb_;
-    sink* sink_;
-
-    state st_;
-    how how_;
-    bool got_header_;
-    bool got_eof_;
-    bool head_response_;
-    bool needs_chunk_close_;
-    bool trailer_headers_;
-    bool chunked_body_ended;
+    static constexpr unsigned buffers_N = 8;
+    impl* impl_;
 };
 
 //------------------------------------------------

include/boost/http_proto/request_parser.hpp

@@ -86,7 +86,55 @@ class request_parser
     explicit
     request_parser(const rts::context& ctx);
 
-    /// @copydoc parser
+    /** Constructor.
+
+        The states of `other` are transferred
+        to the newly constructed object,
+        including the allocated buffer.
+        After construction, the only valid
+        operations on the moved-from object
+        are destruction and assignment.
+
+        Buffer sequences previously obtained
+        using @ref prepare or @ref pull_body
+        remain valid.
+
+        @par Complexity
+        Constant.
+
+        @param other The parser to move from.
+    */
+    request_parser(
+        request_parser&& other) noexcept = default;
+
+    /** Assignment.
+
+        The states of `other` are transferred to
+        `this`, including the allocated buffer.
+        The previous states of `this` are
+        destroyed. After assignment, the only
+        valid operations on the moved-from object
+        are destruction and assignment.
+
+        Buffer sequences previously obtained
+        using @ref prepare or @ref pull_body
+        remain valid.
+
+        @par Complexity
+        Constant.
+
+        @return A reference to this object.
+
+        @param other The parser to assign from.
+    */
+    request_parser& operator=(
+        request_parser&& other) noexcept = default;
+
+    /** Destructor.
+
+        Any views or buffers obtained from this
+        parser become invalid.
+    */
     ~request_parser() = default;
 
     /** Return a read-only view to the parsed request headers.