fix#185, fix#489
* SSE4.2 is detected
* basic_parser uses SSE4.2 if available
* basic_parser tries to parse on the initial buffer and if
it does not find the end of header it shifts to a new
strategy of waiting for the end of header to defeat
slow loris attacks. This coincidentally is also faster
than the previous algorithm.
* detail::read_size_helper is removed
* public function read_size helps determine the optimum
size for calls to a DynamicBuffer's prepare function.
* special case for Asio types which don't conform to
the concept but have their own helper function.
read_size_helper can return zero if the buffer reaches
its maximum size, causing infinite loops in HTTP. The
function maybe_read_size_helper is provided to throw
an exception instead of returning a value for this case.
fix#440
WARNING
multi_buffer constructor now takes a maximum size instead of the
"allocation size". This is a breaking change. The allocation size
feature is removed. To update calling code, remove the allocation
size parameter from call sites.
* multi_buffer now uses a geometric growth algorithm for better performance.
fix#404
Parsing and serialization interfaces have been fine tuned and unified.
For parsing these stream operations are defined:
* read
* read_header
* read_some
* async_read
* async_read_header
* async_read_some
For serialization these stream operations are defined:
* write
* write_header
* write_some
* async_write
* async_write_header
* async_write_some
The concept type traits are renamed for consistency,
and consolidated into a single header file <beast/core/type_traits.hpp>
A new section, Core Concepts, is added to the documentation describing all
of the core utility classes and functions. This also includes a complete
explanation and sample program describing how to write asynchronous initiation
functions and their associated composed operations.
This function converts integers to their decimal
representation as a static string.
In addition, static_string::resize no longer initializes
characters if the new size is larger.
A new function, buffers(), returns an implementation defined object
which wraps a ConstBufferSequence and supports formatting to a
std::ostream.
The function to_string is removed, as the new implementation allows
conversion to string using boost::lexical_cast on the return value
of the call to buffers(). Streaming to an output stream is more
efficient: no dynamic allocations are performed.
Example:
streambuf sb;
std::cout << buffers(sb.data()) << std::endl;
This eliminates beast::write output for dynamic buffers and replaces
it with the function ostream() that wraps a caller provided dynamic
buffer and returns the result as a std::ostream derived object.
Callers may now produce formatted output into any object meeting the
requirements of DynamicBuffer using operator<< and the standard stream
modifiers such as std::endl.
This new technique is more efficient, as implementations of operator<<
can now write directly into the output using std::ostream::write and
std::ostream::put.
Example of use:
beast::streambuf sb;
beast::ostream(sb) << "Hello, world!" << std::endl;
Vinnie Falco
octopus-prime