Finalize Kevin's handrolled parser.

And get rid of the Ragel parser.

This is 7% faster on activitypub, 15% after on twitter and 11% faster
on citm_catalog.

There might be some more optimization opportunities, I did a quick
optimization pass to fix a regression in string parsing, but other
than that I haven't dug much in performance.

.gitattributes

@@ -1,2 +1 @@
-ext/json/ext/parser/parser.c linguist-generated=true
 java/src/json/ext/Parser.java linguist-generated=true

Rakefile

@@ -33,7 +33,6 @@ end rescue nil
 EXT_ROOT_DIR      = 'ext/json/ext'
 EXT_PARSER_DIR    = "#{EXT_ROOT_DIR}/parser"
 EXT_PARSER_DL     = "#{EXT_PARSER_DIR}/parser.#{CONFIG['DLEXT']}"
-RAGEL_PATH        = "#{EXT_PARSER_DIR}/parser.rl"
 EXT_PARSER_SRC    = "#{EXT_PARSER_DIR}/parser.c"
 EXT_GENERATOR_DIR = "#{EXT_ROOT_DIR}/generator"
 EXT_GENERATOR_DL  = "#{EXT_GENERATOR_DIR}/generator.#{CONFIG['DLEXT']}"
@@ -234,53 +233,6 @@ else
     system 'ctags', *Dir['**/*.{rb,c,h,java}']
   end
 
-  file EXT_PARSER_SRC => RAGEL_PATH do
-    cd EXT_PARSER_DIR do
-      if RAGEL_CODEGEN == 'ragel'
-        sh "ragel parser.rl -G2 -o parser.c"
-      else
-        sh "ragel -x parser.rl | #{RAGEL_CODEGEN} -G2"
-      end
-      src = File.read("parser.c").gsub(/[ \t]+$/, '')
-      src.gsub!(/^static const int (JSON_.*=.*);$/, 'enum {\1};')
-      src.gsub!(/^(static const char) (_JSON(?:_\w+)?_nfa_\w+)(?=\[\] =)/, '\1 MAYBE_UNUSED(\2)')
-      src.gsub!(/0 <= ([\( ]+\*[\( ]*p\)+) && \1 <= 31/, "0 <= (signed char)(*(p)) && (*(p)) <= 31")
-      src[0, 0] = "/* This file is automatically generated from parser.rl by using ragel */"
-      File.open("parser.c", "w") {|f| f.print src}
-    end
-  end
-
-  desc "Generate diagrams of ragel parser (ps)"
-  task :ragel_dot_ps do
-    root = 'diagrams'
-    specs = []
-    File.new(RAGEL_PATH).grep(/^\s*machine\s*(\S+);\s*$/) { specs << $1 }
-    for s in specs
-      if RAGEL_DOTGEN == 'ragel'
-        sh "ragel #{RAGEL_PATH} -S#{s} -p -V | dot -Tps -o#{root}/#{s}.ps"
-      else
-        sh "ragel -x #{RAGEL_PATH} -S#{s} | #{RAGEL_DOTGEN} -p|dot -Tps -o#{root}/#{s}.ps"
-      end
-    end
-  end
-
-  desc "Generate diagrams of ragel parser (png)"
-  task :ragel_dot_png do
-    root = 'diagrams'
-    specs = []
-    File.new(RAGEL_PATH).grep(/^\s*machine\s*(\S+);\s*$/) { specs << $1 }
-    for s in specs
-      if RAGEL_DOTGEN == 'ragel'
-        sh "ragel #{RAGEL_PATH} -S#{s} -p -V | dot -Tpng -o#{root}/#{s}.png"
-      else
-        sh "ragel -x #{RAGEL_PATH} -S#{s} | #{RAGEL_DOTGEN} -p|dot -Tpng -o#{root}/#{s}.png"
-      end
-    end
-  end
-
-  desc "Generate diagrams of ragel parser"
-  task :ragel_dot => [ :ragel_dot_png, :ragel_dot_ps ]
-
   desc "Create the gem packages"
   task :package do
     sh "gem build json.gemspec"