--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/net/http/server/parser.rb	Sun Sep 15 11:46:47 2019 +0200
@@ -0,0 +1,151 @@
+require 'net/protocol'
+require 'parslet'
+
+module Net
+  class HTTP < Protocol
+    module Server
+      #
+      # Inspired by:
+      #
+      # * [Thin](https://github.com/macournoyer/thin/blob/master/ext/thin_parser/common.rl)
+      # * [Unicorn](https://github.com/defunkt/unicorn/blob/master/ext/unicorn_http/unicorn_http_common.rl)
+      # * [RFC 2616](http://www.w3.org/Protocols/rfc2616/rfc2616.html)
+      #
+      class Parser < Parslet::Parser
+
+        #
+        # Character Classes
+        #
+        rule(:digit) { match['0-9'] }
+        rule(:digits) { digit.repeat(1) }
+        rule(:xdigit) { digit | match['a-fA-F'] }
+        rule(:upper) { match['A-Z'] }
+        rule(:lower) { match['a-z'] }
+        rule(:alpha) { upper | lower }
+        rule(:alnum) { alpha | digit }
+        rule(:cntrl) { match['\x00-\x1f'] }
+        rule(:ascii) { match['\x00-\x7f'] }
+
+        rule(:lws) { match[" \t"] }
+        rule(:crlf) { str("\r\n") }
+
+        rule(:ctl) { cntrl | str("\x7f") }
+        rule(:text) { lws | (ctl.absnt? >> ascii) }
+
+        rule(:safe) { charset('$', '-', '_', '.') }
+        rule(:extra) { charset('!', '*', "'", '(', ')', ',') }
+        rule(:reserved) { charset(';', '/', '?', ':', '@', '&', '=', '+') }
+        rule(:sorta_safe) { charset('"', '<', '>') }
+
+        rule(:unsafe) { ctl | charset(' ', '#', '%') | sorta_safe }
+        rule(:national) {
+          (alpha | digit | reserved | extra | safe | unsafe).absnt? >> any
+        }
+
+        rule(:unreserved) { alpha | digit | safe | extra | national }
+        rule(:uescape) { str("%u") >> xdigit >> xdigit >> xdigit >> xdigit }
+        rule(:escape) { str("%") >> xdigit >> xdigit }
+        rule(:uchar) { unreserved | uescape | escape | sorta_safe }
+        rule(:pchar) { uchar | charset(':', '@', '&', '=', '+') }
+        rule(:separators) {
+          lws | charset(
+            '(', ')', '<', '>', '@', ',', ';', ':', "\\", '"', '/', '[', ']',
+            '?', '=', '{', '}'
+          )
+        }
+
+        #
+        # Elements
+        #
+        rule(:token) { (ctl | separators).absnt? >> ascii }
+
+        rule(:comment_text) { (str('(') | str(')')).absnt? >> text }
+        rule(:comment) { str('(') >> comment_text.repeat >> str(')') }
+
+        rule(:quoted_pair) { str("\\") >> ascii }
+        rule(:quoted_text) { quoted_pair | str('"').absnt? >> text }
+        rule(:quoted_string) { str('"') >> quoted_text >> str('"') }
+
+        #
+        # URI Elements
+        #
+        rule(:scheme) {
+          (alpha | digit | charset('+', '-', '.')).repeat
+        }
+        rule(:host_name) {
+          (alnum | charset('-', '_', '.')).repeat(1)
+        }
+        rule(:user_info) {
+          (
+            unreserved | escape | charset(';', ':', '&', '=', '+')
+          ).repeat(1)
+        }
+
+        rule(:path) { pchar.repeat(1) >> (str('/') >> pchar.repeat).repeat }
+        rule(:query_string) { (uchar | reserved).repeat }
+        rule(:param) { (pchar | str('/')).repeat }
+        rule(:params) { param >> (str(';') >> param).repeat }
+        rule(:frag) { (uchar | reserved).repeat }
+
+        rule(:uri_path) {
+          (str('/').maybe >> path.maybe).as(:path) >>
+          (str(';') >> params.as(:params)).maybe >>
+          (str('?') >> query_string.as(:query)).maybe >>
+          (str('#') >> frag.as(:fragment)).maybe
+        }
+
+        rule(:uri) {
+          scheme.as(:scheme) >> str(':') >> str('//').maybe >>
+          (user_info.as(:user_info) >> str('@')).maybe >>
+          host_name.as(:host) >>
+          (str(':') >> digits.as(:port)).maybe >>
+          uri_path
+        }
+
+        rule(:request_uri) { str('*') | uri | uri_path }
+
+        #
+        # HTTP Elements
+        #
+        rule(:request_method) { upper.repeat(1,20) | token.repeat(1) }
+
+        rule(:version_number) { digits >> str('.') >> digits }
+        rule(:http_version) { str('HTTP/') >> version_number.as(:version) }
+        rule(:request_line) {
+          request_method.as(:method) >> str(' ') >>
+          request_uri.as(:uri) >> str(' ') >>
+          http_version
+        }
+
+        rule(:header_name) { (str(':').absnt? >> token).repeat(1) }
+        rule(:header_value) {
+          (text | token | separators | quoted_string).repeat(1)
+        }
+
+        rule(:header) {
+          header_name.as(:name) >> str(':') >> lws.repeat(1) >>
+          header_value.as(:value) >> crlf
+        }
+        rule(:request) {
+          request_line >> crlf >>
+          header.repeat.as(:headers) >> crlf
+        }
+
+        root :request
+
+        protected
+
+        #
+        # Creates a matcher for the given characters.
+        #
+        # @param [Array<String>] chars
+        #   The characters to match.
+        #
+        def charset(*chars)
+          match[chars.map { |c| Regexp.escape(c) }.join]
+        end
+
+      end
+    end
+  end
+end