note
	description: "Ancestor for reading/writing basic known entities from and to a particular location specified in concrete descendants of current."
	legal: "See notice at end of class."
	status: "See notice at end of class."
	date: "$Date: 2020-05-19 14:29:33 +0000 (Tue, 19 May 2020) $"
	revision: "$Revision: 104259 $"

deferred class 
	SED_READER_WRITER

feature {NONE} -- Initialization

	default_create
			-- Process instances of classes with no creation clause.
			-- (Default: do nothing.)
			-- (from ANY)
		do
		end
	
feature -- Access

	cleanup
			-- When a reading is stopped, perform the necessary cleanup to perform
			-- another reading or writing.
		require
			is_ready: is_ready_for_reading
		do
		end

	generating_type: TYPE [detachable SED_READER_WRITER]
			-- Type of current object
			-- (type of which it is a direct instance)
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			generating_type_not_void: Result /= Void
		end

	generator: STRING_8
			-- Name of current object's generating class
			-- (base class of the type of which it is a direct instance)
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			generator_not_void: Result /= Void
			generator_not_empty: not Result.is_empty
		end

	read_boolean: BOOLEAN
			-- Read next boolean
		require
			is_ready: is_ready_for_reading
		do
			Result := read_natural_8 = 1
		end

	read_character_32: CHARACTER_32
			-- Read next 32-bits character
		require
			is_ready: is_ready_for_reading
		do
			Result := read_natural_32.to_character_32
		end

	read_character_8: CHARACTER_8
			-- Read next 8-bits character
		require
			is_ready: is_ready_for_reading
		do
			Result := read_natural_8.to_character_8
		end

	read_compressed_integer_32: INTEGER_32
			-- Read next compressed integer_32.
			-- See read_compressed_natural_32 for more details about encoding.
		require
			is_ready: is_ready_for_reading
		do
			Result := read_compressed_natural_32.as_integer_32
		end

	read_compressed_natural_32: NATURAL_32
			-- Read next compressed natural_32.
			-- Depending on first natural_8 value read, it will tell how much more we need to read:
			-- 1 - Of the form 0xxxxxxx (0x00) for values between 0 and 127
			-- 2 - Of the form 10xxxxxx (0x80) for values between 128 and 16382 and one more to read.
			-- 3 - Of the form 110xxxxx (0xC0) for values between 16383 and 2097150 and 2 more to read.
			-- 4 - Of the form 1110xxxx (0xE0) for values between 2097151 and 268435454 and 3 more to read
			-- 5 - Otherwise a full natural_32 to read.
		require
			is_ready: is_ready_for_reading
		local
			l_nat8: NATURAL_8
		do
			l_nat8 := read_natural_8
			if l_nat8 & 128 = 0 then
				Result := l_nat8.to_natural_32
			elseif l_nat8 & 192 = 128 then
				Result := ((l_nat8.as_natural_32 & 63) |<< 8) | read_natural_8.as_natural_32
			elseif l_nat8 & 224 = 192 then
				Result := ((l_nat8.as_natural_32 & 31) |<< 16) | (read_natural_8.as_natural_32 |<< 8) | read_natural_8.as_natural_32
			elseif l_nat8 & 240 = 224 then
				Result := ((l_nat8.as_natural_32 & 15) |<< 24) | (read_natural_8.as_natural_32 |<< 16) | (read_natural_8.as_natural_32 |<< 8) | read_natural_8.as_natural_32
			else
				Result := read_natural_32
			end
		end

	read_immutable_string_32: IMMUTABLE_STRING_32
			-- Read next sequence of characters encoded in UTF-8 as an IMMUTABLE_STRING_32.
		require
			is_ready: is_ready_for_reading
		do
			create Result.make_from_string (read_string_32)
		ensure
			read_string_8_not_void: Result /= Void
		end

	read_immutable_string_8: IMMUTABLE_STRING_8
			-- Read next 8-bits sequence of character as an IMMUTABLE_STRING_8
		require
			is_ready: is_ready_for_reading
		do
			create Result.make_from_string (read_string_8)
		ensure
			read_immutable_string_8_not_void: Result /= Void
		end

	read_integer_16: INTEGER_16
			-- Read next integer_16
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_integer_32: INTEGER_32
			-- Read next integer_32
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_integer_64: INTEGER_64
			-- Read next integer_64
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_integer_8: INTEGER_8
			-- Read next integer_8
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_natural_16: NATURAL_16
			-- Read next natural_16
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_natural_32: NATURAL_32
			-- Read next natural_32
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_natural_64: NATURAL_64
			-- Read next natural_64
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_natural_8: NATURAL_8
			-- Read next natural_8
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_pointer: POINTER
			-- Read next pointer
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_real_32: REAL_32
			-- Read next real_32
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_real_64: REAL_64
			-- Read next real_64
		require
			is_ready: is_ready_for_reading
		deferred
		end

	read_string_32: STRING_32
			-- Read next sequence of characters encoded in UTF-8.
		require
			is_ready: is_ready_for_reading
		local
			u: UTF_CONVERTER
		do
			Result := u.utf_8_string_8_to_string_32 (read_string_8)
		ensure
			read_string_8_not_void: Result /= Void
		end

	read_string_8: STRING_8
			-- Read next 8-bits sequence of character
		require
			is_ready: is_ready_for_reading
		local
			i, nb: INTEGER_32
		do
			nb := read_compressed_natural_32.to_integer_32
			create Result.make (nb)
			from
				i := 1
				nb := nb + 1
			until
				i = nb
			loop
				Result.append_character (read_character_8)
				i := i + 1
			end
		ensure
			read_string_8_not_void: Result /= Void
		end
	
feature -- Comparison

	frozen deep_equal (a: detachable ANY; b: like arg #1): BOOLEAN
			-- Are a and b either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		do
			if a = Void then
				Result := b = Void
			else
				Result := b /= Void and then a.is_deep_equal (b)
			end
		ensure -- from ANY
			instance_free: class
			shallow_implies_deep: standard_equal (a, b) implies Result
			both_or_none_void: (a = Void) implies (Result = (b = Void))
			same_type: (Result and (a /= Void)) implies (b /= Void and then a.same_type (b))
			symmetric: Result implies deep_equal (b, a)
		end

	frozen equal (a: detachable ANY; b: like arg #1): BOOLEAN
			-- Are a and b either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		do
			if a = Void then
				Result := b = Void
			else
				Result := b /= Void and then a.is_equal (b)
			end
		ensure -- from ANY
			instance_free: class
			definition: Result = (a = Void and b = Void) or else ((a /= Void and b /= Void) and then a.is_equal (b))
		end

	frozen is_deep_equal alias "≡≡≡" (other: SED_READER_WRITER): BOOLEAN
			-- Are Current and other attached to isomorphic object structures?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		external
			"built_in"
		ensure -- from ANY
			shallow_implies_deep: standard_is_equal (other) implies Result
			same_type: Result implies same_type (other)
			symmetric: Result implies other.is_deep_equal (Current)
		end

	is_equal (other: SED_READER_WRITER): BOOLEAN
			-- Is other attached to an object considered
			-- equal to current object?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		external
			"built_in"
		ensure -- from ANY
			symmetric: Result implies other ~ Current
			consistent: standard_is_equal (other) implies Result
		end

	frozen standard_equal (a: detachable ANY; b: like arg #1): BOOLEAN
			-- Are a and b either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		do
			if a = Void then
				Result := b = Void
			else
				Result := b /= Void and then a.standard_is_equal (b)
			end
		ensure -- from ANY
			instance_free: class
			definition: Result = (a = Void and b = Void) or else ((a /= Void and b /= Void) and then a.standard_is_equal (b))
		end

	frozen standard_is_equal alias "≜" (other: SED_READER_WRITER): BOOLEAN
			-- Is other attached to an object of the same type
			-- as current object, and field-by-field identical to it?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		external
			"built_in"
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
		end
	
feature -- Status report

	conforms_to (other: ANY): BOOLEAN
			-- Does type of current object conform to type
			-- of other (as per Eiffel: The Language, chapter 13)?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		external
			"built_in"
		end

	is_pointer_value_stored: BOOLEAN
			-- Is value of a POINTER stored?

	is_ready_for_reading: BOOLEAN
			-- Is Current ready for future read operations?
		deferred
		end

	is_ready_for_writing: BOOLEAN
			-- Is Current ready for future write operations?
		deferred
		end

	same_type (other: ANY): BOOLEAN
			-- Is type of current object identical to type of other?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		external
			"built_in"
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))
		end
	
feature -- Element change

	write_boolean (v: BOOLEAN)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		do
			if v then
				write_natural_8 (1)
			else
				write_natural_8 (0)
			end
		end

	write_character_32 (v: CHARACTER_32)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		do
			write_natural_32 (v.natural_32_code)
		end

	write_character_8 (v: CHARACTER_8)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		do
			write_natural_8 (v.code.to_natural_8)
		end

	write_compressed_integer_32 (v: INTEGER_32)
			-- Write v as a compressed integer_32.
			-- See write_compressed_natural_32 for details about encoding.
		require
			is_ready: is_ready_for_writing
		do
			write_compressed_natural_32 (v.as_natural_32)
		end

	write_compressed_natural_32 (v: NATURAL_32)
			-- Write v as a compressed natural_32.
			-- Depending on value of v, it will tell how many natural_8 will
			-- be written. Below here is the actual encoding where x represents
			-- a meaningful bit for v and the last number in parenthesis is the
			-- marker value in hexadecimal which is added to the value of v.
			-- 1 - For values between 0 and 127, write 0xxxxxxx (0x00).
			-- 2 - For values between 128 and 16382, write 0x10xxxxxx xxxxxxxx (0xE0).
			-- 3 - For values between 16383 and 2097150, write 0x110xxxxx xxxxxxxx xxxxxxxx (0xC0).
			-- 4 - For values between 2097151 and 268435454, write 0x1110xxx xxxxxxxx xxxxxxxx xxxxxxxx (0xE0).
			-- 5 - Otherwise write v as a full natural_32.
		require
			is_ready: is_ready_for_writing
		do
			if v < 16384 then
				if v < 128 then
					write_natural_8 (v.as_natural_8)
				else
					write_natural_8 ((((v | 32768) & 65280) |>> 8).as_natural_8)
					write_natural_8 ((v & 255).as_natural_8)
				end
			elseif v < 2097152 then
				write_natural_8 ((((v | 12582912) & 16711680) |>> 16).as_natural_8)
				write_natural_8 (((v & 65280) |>> 8).as_natural_8)
				write_natural_8 ((v & 255).as_natural_8)
			elseif v < 268435456 then
				write_natural_8 ((((v | 3758096384) & 4278190080) |>> 24).as_natural_8)
				write_natural_8 (((v & 16711680) |>> 16).as_natural_8)
				write_natural_8 (((v & 65280) |>> 8).as_natural_8)
				write_natural_8 ((v & 255).as_natural_8)
			else
				write_natural_8 (240)
				write_natural_32 (v)
			end
		end

	write_immutable_string_8 (v: IMMUTABLE_STRING_8)
		obsolete "Use `write_string_8' instead. [2017-05-31]"
			-- Write v.
		require
			is_ready: is_ready_for_writing
			v_not_void: v /= Void
		do
			write_string_8 (v)
		end

	write_integer_16 (v: INTEGER_16)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_integer_32 (v: INTEGER_32)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_integer_64 (v: INTEGER_64)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_integer_8 (v: INTEGER_8)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_natural_16 (v: NATURAL_16)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_natural_32 (v: NATURAL_32)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_natural_64 (v: NATURAL_64)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_natural_8 (v: NATURAL_8)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_pointer (v: POINTER)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_real_32 (v: REAL_32)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_real_64 (v: REAL_64)
			-- Write v.
		require
			is_ready: is_ready_for_writing
		deferred
		end

	write_string_32 (v: READABLE_STRING_GENERAL)
			-- Write v in UTF-8 format.
		require
			is_ready: is_ready_for_writing
			v_not_void: v /= Void
		local
			u: UTF_CONVERTER
		do
			write_string_8 (u.utf_32_string_to_utf_8_string_8 (v))
		end

	write_string_8 (v: READABLE_STRING_8)
			-- Write v.
		require
			is_ready: is_ready_for_writing
			v_not_void: v /= Void
		local
			i, nb: INTEGER_32
		do
			write_compressed_natural_32 (v.count.to_natural_32)
			from
				i := 1
				nb := v.count + 1
			until
				i = nb
			loop
				write_character_8 (v.item (i))
				i := i + 1
			end
		end
	
feature -- Duplication

	frozen clone (other: detachable ANY): like other
		obsolete "Use `twin' instead. [2017-05-31]"
			-- Void if other is void; otherwise new object
			-- equal to other
			--
			-- For non-void other, clone calls copy;
			-- to change copying/cloning semantics, redefine copy.
			-- (from ANY)
		do
			if other /= Void then
				Result := other.twin
			end
		ensure -- from ANY
			instance_free: class
			equal: Result ~ other
		end

	copy (other: SED_READER_WRITER)
			-- Update current object using fields of object attached
			-- to other, so as to yield equal objects.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		external
			"built_in"
		ensure -- from ANY
			is_equal: Current ~ other
		end

	frozen deep_clone (other: detachable ANY): like other
		obsolete "Use `deep_twin' instead. [2017-05-31]"
			-- Void if other is void: otherwise, new object structure
			-- recursively duplicated from the one attached to other
			-- (from ANY)
		do
			if other /= Void then
				Result := other.deep_twin
			end
		ensure -- from ANY
			instance_free: class
			deep_equal: deep_equal (other, Result)
		end

	frozen deep_copy (other: SED_READER_WRITER)
			-- Effect equivalent to that of:
			--		copy (other . deep_twin)
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		do
			copy (other.deep_twin)
		ensure -- from ANY
			deep_equal: deep_equal (Current, other)
		end

	frozen deep_twin: SED_READER_WRITER
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			deep_twin_not_void: Result /= Void
			deep_equal: deep_equal (Current, Result)
		end

	frozen standard_clone (other: detachable ANY): like other
		obsolete "Use `standard_twin' instead. [2017-05-31]"
			-- Void if other is void; otherwise new object
			-- field-by-field identical to other.
			-- Always uses default copying semantics.
			-- (from ANY)
		do
			if other /= Void then
				Result := other.standard_twin
			end
		ensure -- from ANY
			instance_free: class
			equal: standard_equal (Result, other)
		end

	frozen standard_copy (other: SED_READER_WRITER)
			-- Copy every field of other onto corresponding field
			-- of current object.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		external
			"built_in"
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)
		end

	frozen standard_twin: SED_READER_WRITER
			-- New object field-by-field identical to other.
			-- Always uses default copying semantics.
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)
		end

	frozen twin: SED_READER_WRITER
			-- New object equal to Current
			-- twin calls copy; to change copying/twinning semantics, redefine copy.
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result ~ Current
		end
	
feature -- Basic operations

	frozen as_attached: attached SED_READER_WRITER
		obsolete "Remove calls to this feature. [2017-05-31]"
			-- Attached version of Current.
			-- (Can be used during transitional period to convert
			-- non-void-safe classes to void-safe ones.)
			-- (from ANY)
		do
			Result := Current
		end

	frozen default: detachable SED_READER_WRITER
			-- Default value of object's type
			-- (from ANY)
		do
		end

	frozen default_pointer: POINTER
			-- Default value of type POINTER
			-- (Avoid the need to write p.default for
			-- some p of type POINTER.)
			-- (from ANY)
		do
		ensure -- from ANY
			instance_free: class
		end

	default_rescue
			-- Process exception for routines with no Rescue clause.
			-- (Default: do nothing.)
			-- (from ANY)
		do
		end

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)
		do
		ensure -- from ANY
			instance_free: class
		end
	
feature -- Header/Footer

	read_footer
			-- Action being executed after finishing to read data.
		require
			is_ready: is_ready_for_reading
		do
		end

	read_header
			-- Action being executed before starting to read data.
		require
			is_ready: is_ready_for_reading
		do
		end

	write_footer
			-- Action being executed after finishing to write data.
		require
			is_ready: is_ready_for_writing
		do
		end

	write_header
			-- Action being executed before starting to write data.
		require
			is_ready: is_ready_for_writing
		do
		end
	
feature -- Output

	Io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)
		once
			create Result;
			Result.set_output_default
		ensure -- from ANY
			instance_free: class
			io_not_void: Result /= Void
		end

	out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- (from ANY)
		do
			Result := tagged_out
		ensure -- from ANY
			out_not_void: Result /= Void
		end

	print (o: detachable ANY)
			-- Write terse external representation of o
			-- on standard output.
			-- (from ANY)
		local
			s: READABLE_STRING_8
		do
			if attached o then
				s := o.out
				if attached {READABLE_STRING_32} s as s32 then
					Io.put_string_32 (s32)
				elseif attached {READABLE_STRING_8} s as s8 then
					Io.put_string (s8)
				else
					Io.put_string_32 (s.as_string_32)
				end
			end
		ensure -- from ANY
			instance_free: class
		end

	frozen tagged_out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- (from ANY)
		external
			"built_in"
		ensure -- from ANY
			tagged_out_not_void: Result /= Void
		end
	
feature -- Platform

	Operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
		once
			create Result
		ensure -- from ANY
			instance_free: class
			operating_environment_not_void: Result /= Void
		end
	
feature {NONE} -- Retrieval

	frozen internal_correct_mismatch
			-- Called from runtime to perform a proper dynamic dispatch on correct_mismatch
			-- from MISMATCH_CORRECTOR.
			-- (from ANY)
		local
			l_msg: STRING_32
			l_exc: EXCEPTIONS
		do
			if attached {MISMATCH_CORRECTOR} Current as l_corrector then
				l_corrector.correct_mismatch
			else
				create l_msg.make_from_string ("Mismatch: ".as_string_32)
				create l_exc;
				l_msg.append (generating_type.name_32);
				l_exc.raise_retrieval_exception (l_msg)
			end
		end
	
feature -- Settings

	set_is_pointer_value_stored (v: like is_pointer_value_stored)
			-- Set is_pointer_value_stored with v.
		do
			is_pointer_value_stored := v
		ensure
			is_pointer_value_stored_set: is_pointer_value_stored = v
		end
	
invariant
		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

note
	library: "EiffelBase: Library of reusable components for Eiffel."
	copyright: "Copyright (c) 1984-2020, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
		Eiffel Software
		5949 Hollister Ave., Goleta, CA 93117 USA
		Telephone 805-685-1006, Fax 805-685-6869
		Website http://www.eiffel.com
		Customer support http://support.eiffel.com
	]"

end -- class SED_READER_WRITER

Generated by ISE EiffelStudio