Files
boost_beast/include/beast/http/impl/write.ipp
T
Vinnie Falco ff15cf8688 Refactor chunked-encoding serialization:
New buffer sequence classes are provided to allow full
control over the serialization of chunk-encoded message
payloads:

* chunk_header

    A ConstBufferSequence representing the chunk header.
    It includes a hexadecimal-encoded size, an optional
    set of chunk extensions, and the trailing CRLF
    required to denote the end of the chunk header.

    This allows the caller to manually serialize the chunk
    body in one or more calls to a stream output function.
    The caller must also output an object of type `chunk_crlf`
    to the stream to indicate the end of the chunk body.

* chunk_crlf

    A small ConstBufferSequence that simply represents
    the two character sequence "\r\n" (CRLF). This is needed
    for the case where the caller wants to output a chunk
    body as a series of buffers (i.e. "chunking a chunk").

* chunk_body

    A ConstBufferSequence representing a complete chunk.
    This includes the size, an optional set of chunk extensions,
    a caller provided buffer containing the body, and the
    required CRLF that follows.

* chunk_final

    A ConstBufferSequence representing a final chunk. It
    includes an optional set of caller-provided field trailers

* chunk_extensions

    A container for building a set of chunk extensions to use
    during serialization. The use of the container is optional,
    callers may provide their own buffer containing a correctly
    formatted set of chunk extensions, or they may use their
    own convenience container which meets the requirements.

The basic_fields container is modified to allow construction
outside the context of a message. The container can be used
to provide trailers to `chunk_final`.

Actions Required:

* Remove references to ChunkDecorators. Use the new chunk-encoding
  buffer sequences to manually produce a chunked payload body in
  the case where control over the chunk-extensions and/or trailers
  is required.
2017-07-20 08:15:31 -07:00

887 lines
22 KiB
C++

//
// Copyright (c) 2013-2017 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)
//
#ifndef BEAST_HTTP_IMPL_WRITE_IPP
#define BEAST_HTTP_IMPL_WRITE_IPP
#include <beast/http/type_traits.hpp>
#include <beast/core/bind_handler.hpp>
#include <beast/core/ostream.hpp>
#include <beast/core/handler_alloc.hpp>
#include <beast/core/handler_ptr.hpp>
#include <beast/core/type_traits.hpp>
#include <beast/core/detail/config.hpp>
#include <boost/asio/handler_alloc_hook.hpp>
#include <boost/asio/handler_continuation_hook.hpp>
#include <boost/asio/handler_invoke_hook.hpp>
#include <boost/asio/write.hpp>
#include <boost/optional.hpp>
#include <boost/throw_exception.hpp>
#include <ostream>
#include <sstream>
namespace beast {
namespace http {
namespace detail {
template<
class Stream, class Handler,
bool isRequest, class Body, class Fields>
class write_some_op
{
Stream& s_;
serializer<isRequest,Body, Fields>& sr_;
Handler h_;
class lambda
{
write_some_op& op_;
public:
bool invoked = false;
explicit
lambda(write_some_op& op)
: op_(op)
{
}
template<class ConstBufferSequence>
void
operator()(error_code& ec,
ConstBufferSequence const& buffers)
{
invoked = true;
ec.assign(0, ec.category());
return op_.s_.async_write_some(
buffers, std::move(op_));
}
};
public:
write_some_op(write_some_op&&) = default;
write_some_op(write_some_op const&) = default;
template<class DeducedHandler>
write_some_op(DeducedHandler&& h, Stream& s,
serializer<isRequest, Body, Fields>& sr)
: s_(s)
, sr_(sr)
, h_(std::forward<DeducedHandler>(h))
{
}
void
operator()();
void
operator()(error_code ec,
std::size_t bytes_transferred);
friend
void* asio_handler_allocate(
std::size_t size, write_some_op* op)
{
using boost::asio::asio_handler_allocate;
return asio_handler_allocate(
size, std::addressof(op->h_));
}
friend
void asio_handler_deallocate(
void* p, std::size_t size, write_some_op* op)
{
using boost::asio::asio_handler_deallocate;
asio_handler_deallocate(
p, size, std::addressof(op->h_));
}
friend
bool asio_handler_is_continuation(write_some_op* op)
{
using boost::asio::asio_handler_is_continuation;
return asio_handler_is_continuation(
std::addressof(op->h_));
}
template<class Function>
friend
void asio_handler_invoke(Function&& f, write_some_op* op)
{
using boost::asio::asio_handler_invoke;
asio_handler_invoke(f, std::addressof(op->h_));
}
};
template<
class Stream, class Handler,
bool isRequest, class Body, class Fields>
void
write_some_op<
Stream, Handler, isRequest, Body, Fields>::
operator()()
{
error_code ec;
if(! sr_.is_done())
{
lambda f{*this};
sr_.next(ec, f);
if(ec)
{
BOOST_ASSERT(! f.invoked);
return s_.get_io_service().post(
bind_handler(std::move(*this), ec, 0));
}
if(f.invoked)
{
// *this has been moved from,
// cannot access members here.
return;
}
// What else could it be?
BOOST_ASSERT(sr_.is_done());
}
return s_.get_io_service().post(
bind_handler(std::move(*this), ec, 0));
}
template<
class Stream, class Handler,
bool isRequest, class Body, class Fields>
void
write_some_op<
Stream, Handler, isRequest, Body, Fields>::
operator()(
error_code ec, std::size_t bytes_transferred)
{
if(! ec)
{
sr_.consume(bytes_transferred);
if(sr_.is_done())
if(! sr_.keep_alive())
ec = error::end_of_stream;
}
h_(ec);
}
//------------------------------------------------------------------------------
struct serializer_is_header_done
{
template<
bool isRequest, class Body, class Fields>
bool
operator()(
serializer<isRequest, Body, Fields>& sr) const
{
return sr.is_header_done();
}
};
struct serializer_is_done
{
template<
bool isRequest, class Body, class Fields>
bool
operator()(
serializer<isRequest, Body, Fields>& sr) const
{
return sr.is_done();
}
};
//------------------------------------------------------------------------------
template<
class Stream, class Handler, class Predicate,
bool isRequest, class Body, class Fields>
class write_op
{
int state_ = 0;
Stream& s_;
serializer<isRequest, Body, Fields>& sr_;
Handler h_;
public:
write_op(write_op&&) = default;
write_op(write_op const&) = default;
template<class DeducedHandler>
write_op(DeducedHandler&& h, Stream& s,
serializer<isRequest, Body, Fields>& sr)
: s_(s)
, sr_(sr)
, h_(std::forward<DeducedHandler>(h))
{
}
void
operator()(error_code ec);
friend
void* asio_handler_allocate(
std::size_t size, write_op* op)
{
using boost::asio::asio_handler_allocate;
return asio_handler_allocate(
size, std::addressof(op->h_));
}
friend
void asio_handler_deallocate(
void* p, std::size_t size, write_op* op)
{
using boost::asio::asio_handler_deallocate;
asio_handler_deallocate(
p, size, std::addressof(op->h_));
}
friend
bool asio_handler_is_continuation(write_op* op)
{
using boost::asio::asio_handler_is_continuation;
return op->state_ >= 3 ||
asio_handler_is_continuation(
std::addressof(op->h_));
}
template<class Function>
friend
void asio_handler_invoke(Function&& f, write_op* op)
{
using boost::asio::asio_handler_invoke;
asio_handler_invoke(
f, std::addressof(op->h_));
}
};
template<
class Stream, class Handler, class Predicate,
bool isRequest, class Body, class Fields>
void
write_op<Stream, Handler, Predicate,
isRequest, Body, Fields>::
operator()(error_code ec)
{
if(ec)
goto upcall;
switch(state_)
{
case 0:
{
if(Predicate{}(sr_))
{
state_ = 1;
return s_.get_io_service().post(
bind_handler(std::move(*this), ec));
}
state_ = 2;
return beast::http::async_write_some(
s_, sr_, std::move(*this));
}
case 1:
goto upcall;
case 2:
state_ = 3;
BEAST_FALLTHROUGH;
case 3:
{
if(Predicate{}(sr_))
goto upcall;
return beast::http::async_write_some(
s_, sr_, std::move(*this));
}
}
upcall:
h_(ec);
}
//------------------------------------------------------------------------------
template<class Stream, class Handler,
bool isRequest, class Body, class Fields>
class write_msg_op
{
struct data
{
Stream& s;
serializer<isRequest, Body, Fields> sr;
data(Handler&, Stream& s_, message<
isRequest, Body, Fields>& m_)
: s(s_)
, sr(m_)
{
}
};
handler_ptr<data, Handler> d_;
public:
write_msg_op(write_msg_op&&) = default;
write_msg_op(write_msg_op const&) = default;
template<class DeducedHandler, class... Args>
write_msg_op(DeducedHandler&& h, Stream& s, Args&&... args)
: d_(std::forward<DeducedHandler>(h),
s, std::forward<Args>(args)...)
{
}
void
operator()();
void
operator()(error_code ec);
friend
void* asio_handler_allocate(
std::size_t size, write_msg_op* op)
{
using boost::asio::asio_handler_allocate;
return asio_handler_allocate(
size, std::addressof(op->d_.handler()));
}
friend
void asio_handler_deallocate(
void* p, std::size_t size, write_msg_op* op)
{
using boost::asio::asio_handler_deallocate;
asio_handler_deallocate(
p, size, std::addressof(op->d_.handler()));
}
friend
bool asio_handler_is_continuation(write_msg_op* op)
{
using boost::asio::asio_handler_is_continuation;
return asio_handler_is_continuation(
std::addressof(op->d_.handler()));
}
template<class Function>
friend
void asio_handler_invoke(Function&& f, write_msg_op* op)
{
using boost::asio::asio_handler_invoke;
asio_handler_invoke(
f, std::addressof(op->d_.handler()));
}
};
template<class Stream, class Handler,
bool isRequest, class Body, class Fields>
void
write_msg_op<
Stream, Handler, isRequest, Body, Fields>::
operator()()
{
auto& d = *d_;
return async_write(d.s, d.sr, std::move(*this));
}
template<class Stream, class Handler,
bool isRequest, class Body, class Fields>
void
write_msg_op<
Stream, Handler, isRequest, Body, Fields>::
operator()(error_code ec)
{
d_.invoke(ec);
}
//------------------------------------------------------------------------------
template<class Stream>
class write_some_lambda
{
Stream& stream_;
public:
bool invoked = false;
std::size_t bytes_transferred = 0;
explicit
write_some_lambda(Stream& stream)
: stream_(stream)
{
}
template<class ConstBufferSequence>
void
operator()(error_code& ec,
ConstBufferSequence const& buffers)
{
invoked = true;
bytes_transferred =
stream_.write_some(buffers, ec);
}
};
template<class Stream>
class write_lambda
{
Stream& stream_;
public:
bool invoked = false;
std::size_t bytes_transferred = 0;
explicit
write_lambda(Stream& stream)
: stream_(stream)
{
}
template<class ConstBufferSequence>
void
operator()(error_code& ec,
ConstBufferSequence const& buffers)
{
invoked = true;
bytes_transferred = boost::asio::write(
stream_, buffers, ec);
}
};
} // detail
//------------------------------------------------------------------------------
namespace detail {
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write_some(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
error_code& ec)
{
if(! sr.is_done())
{
write_some_lambda<SyncWriteStream> f{stream};
sr.next(ec, f);
if(ec)
return;
if(f.invoked)
sr.consume(f.bytes_transferred);
if(sr.is_done())
if(! sr.keep_alive())
ec = error::end_of_stream;
return;
}
if(! sr.keep_alive())
ec = error::end_of_stream;
else
ec.assign(0, ec.category());
}
template<
class AsyncWriteStream,
bool isRequest, class Body, class Fields,
class WriteHandler>
async_return_type<WriteHandler, void(error_code)>
async_write_some(
AsyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
WriteHandler&& handler)
{
async_completion<WriteHandler,
void(error_code)> init{handler};
detail::write_some_op<AsyncWriteStream,
handler_type<WriteHandler, void(error_code)>,
isRequest, Body, Fields>{
init.completion_handler, stream, sr}();
return init.result.get();
}
} // detail
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write_some(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
error_code ec;
write_some(stream, sr, ec);
if(ec)
BOOST_THROW_EXCEPTION(system_error{ec});
}
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write_some(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
error_code& ec)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
detail::write_some(stream, sr, ec);
}
template<
class AsyncWriteStream,
bool isRequest, class Body, class Fields,
class WriteHandler>
async_return_type<WriteHandler, void(error_code)>
async_write_some(
AsyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
WriteHandler&& handler)
{
static_assert(is_async_write_stream<
AsyncWriteStream>::value,
"AsyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
return detail::async_write_some(stream, sr,
std::forward<WriteHandler>(handler));
}
//------------------------------------------------------------------------------
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write_header(SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
error_code ec;
write_header(stream, sr, ec);
if(ec)
BOOST_THROW_EXCEPTION(system_error{ec});
}
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write_header(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
error_code& ec)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
sr.split(true);
if(! sr.is_header_done())
{
detail::write_lambda<SyncWriteStream> f{stream};
do
{
sr.next(ec, f);
if(ec)
return;
BOOST_ASSERT(f.invoked);
sr.consume(f.bytes_transferred);
}
while(! sr.is_header_done());
}
else
{
ec.assign(0, ec.category());
}
}
template<
class AsyncWriteStream,
bool isRequest, class Body, class Fields,
class WriteHandler>
async_return_type<WriteHandler, void(error_code)>
async_write_header(
AsyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
WriteHandler&& handler)
{
static_assert(is_async_write_stream<
AsyncWriteStream>::value,
"AsyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
sr.split(true);
async_completion<WriteHandler,
void(error_code)> init{handler};
detail::write_op<AsyncWriteStream, handler_type<
WriteHandler, void(error_code)>,
detail::serializer_is_header_done,
isRequest, Body, Fields>{
init.completion_handler, stream, sr}(
error_code{}, 0);
return init.result.get();
}
//------------------------------------------------------------------------------
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
error_code ec;
write(stream, sr, ec);
if(ec)
BOOST_THROW_EXCEPTION(system_error{ec});
}
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write(
SyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
error_code& ec)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
sr.split(false);
for(;;)
{
write_some(stream, sr, ec);
if(ec)
return;
if(sr.is_done())
break;
}
}
template<
class AsyncWriteStream,
bool isRequest, class Body, class Fields,
class WriteHandler>
async_return_type<WriteHandler, void(error_code)>
async_write(
AsyncWriteStream& stream,
serializer<isRequest, Body, Fields>& sr,
WriteHandler&& handler)
{
static_assert(is_async_write_stream<
AsyncWriteStream>::value,
"AsyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
sr.split(false);
async_completion<WriteHandler,
void(error_code)> init{handler};
detail::write_op<AsyncWriteStream, handler_type<
WriteHandler, void(error_code)>,
detail::serializer_is_done, isRequest, Body, Fields>{
init.completion_handler, stream, sr}(error_code{});
return init.result.get();
}
//------------------------------------------------------------------------------
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write(
SyncWriteStream& stream,
message<isRequest, Body, Fields> const& msg)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
error_code ec;
write(stream, msg, ec);
if(ec)
BOOST_THROW_EXCEPTION(system_error{ec});
}
template<
class SyncWriteStream,
bool isRequest, class Body, class Fields>
void
write(
SyncWriteStream& stream,
message<isRequest, Body, Fields> const& msg,
error_code& ec)
{
static_assert(is_sync_write_stream<SyncWriteStream>::value,
"SyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
serializer<isRequest, Body, Fields> sr{msg};
write(stream, sr, ec);
}
template<
class AsyncWriteStream,
bool isRequest, class Body, class Fields,
class WriteHandler>
async_return_type<
WriteHandler, void(error_code)>
async_write(
AsyncWriteStream& stream,
message<isRequest, Body, Fields>& msg,
WriteHandler&& handler)
{
static_assert(
is_async_write_stream<AsyncWriteStream>::value,
"AsyncWriteStream requirements not met");
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
async_completion<WriteHandler,
void(error_code)> init{handler};
detail::write_msg_op<AsyncWriteStream, handler_type<
WriteHandler, void(error_code)>, isRequest,
Body, Fields>{init.completion_handler,
stream, msg}();
return init.result.get();
}
//------------------------------------------------------------------------------
namespace detail {
template<class Serializer>
class write_ostream_lambda
{
std::ostream& os_;
Serializer& sr_;
public:
write_ostream_lambda(std::ostream& os,
Serializer& sr)
: os_(os)
, sr_(sr)
{
}
template<class ConstBufferSequence>
void
operator()(error_code& ec,
ConstBufferSequence const& buffers) const
{
ec.assign(0, ec.category());
if(os_.fail())
return;
std::size_t bytes_transferred = 0;
using boost::asio::buffer_cast;
using boost::asio::buffer_size;
for(auto it = buffers.begin();
it != buffers.end(); ++it)
{
boost::asio::const_buffer b = *it;
auto const n = buffer_size(b);
os_.write(buffer_cast<char const*>(b), n);
if(os_.fail())
return;
bytes_transferred += n;
}
sr_.consume(bytes_transferred);
}
};
} // detail
template<class Fields>
std::ostream&
operator<<(std::ostream& os,
header<true, Fields> const& h)
{
typename Fields::reader fr{
h, h.version, h.method()};
return os << buffers(fr.get());
}
template<class Fields>
std::ostream&
operator<<(std::ostream& os,
header<false, Fields> const& h)
{
typename Fields::reader fr{
h, h.version, h.result_int()};
return os << buffers(fr.get());
}
template<bool isRequest, class Body, class Fields>
std::ostream&
operator<<(std::ostream& os,
message<isRequest, Body, Fields> const& msg)
{
static_assert(is_body<Body>::value,
"Body requirements not met");
static_assert(is_body_reader<Body>::value,
"BodyReader requirements not met");
serializer<isRequest, Body, Fields> sr{msg};
error_code ec;
detail::write_ostream_lambda<decltype(sr)> f{os, sr};
do
{
sr.next(ec, f);
if(os.fail())
break;
if(ec == error::end_of_stream)
ec.assign(0, ec.category());
if(ec)
{
os.setstate(std::ios::failbit);
break;
}
}
while(! sr.is_done());
return os;
}
} // http
} // beast
#endif