fix#242
* Add public constructors
* Add handler_ptr::empty()
* Add handler_ptr::element_type
* Remove make_handler_ptr free function
* Compiler error if element_type is an array type
* handler_ptr::get() returns nullptr if no object is owned
fix#215
This change guarantees that temporary memory allocated
through the asio hooks by the Beast implementation is
deallocated before invoking the final handler when performing
composed operations.
The change is accomplished by replacing std::shared_ptr with
a thread-safe custom container handler_ptr to manage composed
operation state. The container tracks other instances which
manage the same object and resets them in a safe way before
invoking the final handler.
handler_ptr is provided as a public interface so that users of
this library can utilize the same idiom to write their own
composed operations.
fix#171
Several names and HTTP identifiers are renamed to be
more consistent, self-explanatory, and concise:
* "Fields" is a collection of HTTP header fields (rfc7230 section 3.2)
* "Header" is the Start Line plus Fields. Another way to look at it is,
the HTTP message minus the body.
* `basic_fields` replaces `basic_headers`
* `fields` replaces `headers`
* `Fields` replaces `Headers` in template parameter lists
* `header` replaces `message_headers`
* `header::fields` replaces `message_headers::fields`
The changes are cosmetic and do not affect run-time behavior.
Vinnie Falco