indexing
	description: "Encapsulation of standard implementation of IStream interface."
	legal: "See notice at end of class."
	status: "See notice at end of class."
	date: "$Date: 2008-02-14 02:30:05 -0800 (Thu, 14 Feb 2008) $"
	revision: "$Revision: 72306 $"

class interface
	ECOM_STREAM


create 
	make_from_other (other: ECOM_INTERFACE)
			-- Make from other Queriable.
			-- (from ECOM_QUERIABLE)
		require -- from ECOM_QUERIABLE
			non_void_other: other /= Void
		ensure -- from ECOM_QUERIABLE
			valid_initializer: initializer /= default_pointer
			exists: exists

	make_from_pointer (cpp_obj: POINTER)
			-- Make from pointer
		require -- from ECOM_QUERIABLE
			non_default_pointer: cpp_obj /= default_pointer
		ensure -- from ECOM_QUERIABLE
			valid_initializer: initializer /= default_pointer
			exists: exists

feature -- Access

	access_time: WEL_FILE_TIME
			-- Access time

	creation_time: WEL_FILE_TIME
			-- Creation time

	description (stat_flag: INTEGER_32): ECOM_STATSTG
			-- STATSTG structure
			-- See class ECOM_STAT_FLAGS for `stat_flag' values.
		require
			valid_stat_flag: is_valid_stat_flag (stat_flag)
		ensure
			Result /= Void

	end_of_stream: BOOLEAN
			-- Is current seek pointer at end of stream?
			-- Valid only after read ,update_end_of_stream, start, or finish.

	exception_manager: EXCEPTION_MANAGER
			-- Exception manager
			-- (from EXCEPTION_MANAGER_FACTORY)
		ensure -- from EXCEPTION_MANAGER_FACTORY
			exception_manager_not_void: Result /= Void

	exists: BOOLEAN
			-- Is wrapped structure initialized?
			-- (from ECOM_QUERIABLE)

	generating_type: STRING_8
			-- Name of current object's generating type
			-- (type of which it is a direct instance)
			-- (from ANY)
		ensure -- from ANY
			generating_type_not_void: Result /= Void
			generating_type_not_empty: not Result.is_empty

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

	is_valid_lock (lock: INTEGER_32): BOOLEAN
			-- Is `lock' a valid locktype?
			-- (from ECOM_LOCK_TYPES)

	is_valid_seek (seek: INTEGER_32): BOOLEAN
			-- Is seek a valid IStorage and IStream seek flag?
			-- (from ECOM_STREAM_SEEK)

	is_valid_stat_flag (flag: INTEGER_32): BOOLEAN
			-- Is `flag' a valid stat flag?
			-- (from ECOM_STAT_FLAGS)

	item: POINTER
			-- Pointer to COM object wrapper.
			-- (from ECOM_QUERIABLE)

	last_boolean: BOOLEAN
			-- last read BOOLEAN

	last_character: CHARACTER_8
			-- last read CHARACTER

	last_integer: INTEGER_32
			-- last read INTEGER

	last_real: REAL_32
			-- last read REAL

	last_string: STRING_8
			-- last read STRING

	lock_exclusive: INTEGER_32
			-- Attempts to read or write this stream by other stream openings
			-- return error EOLE_STG_E_ACCESSDENIED.
			-- (from ECOM_LOCK_TYPES)

	lock_onlyonce: INTEGER_32
			-- If lock is granted, no other EOLE_LOCK_ONLYONCE lock can be
			-- obtained on bytes in given region. Usually this lock type
			-- is an alias for some other lock type and other semantics might occur
			-- as a side effect.
			-- (from ECOM_LOCK_TYPES)

	lock_write: INTEGER_32
			-- If lock is granted, specified region of stream
			-- can be read by calling IStream.Read from any opening of
			-- this stream. Attempts to write to this region from any opening
			-- of this stream other than the one to which lock was granted
			-- returns error EOLE_STG_E_ACCESSDENIED.
			-- (from ECOM_LOCK_TYPES)

	locks_supported: INTEGER_32
			-- Types of region locking supported by stream

	modification_time: WEL_FILE_TIME
			-- Modification time

	name: STRING_8
			-- Name

	size: ECOM_ULARGE_INTEGER
			-- Size in bytes

	statflag_default: INTEGER_32
			-- Indicate that this is not used for property
			-- (from ECOM_STAT_FLAGS)

	statflag_noname: INTEGER_32
			-- Indicate that this is not used for property
			-- (from ECOM_STAT_FLAGS)

	stream_seek_cur: INTEGER_32
			-- Sets seek position relative to
			-- current position of stream
			-- (from ECOM_STREAM_SEEK)

	stream_seek_end: INTEGER_32
			-- Sets seek position relative to
			-- current end of stream
			-- (from ECOM_STREAM_SEEK)

	stream_seek_set: INTEGER_32
			-- Sets seek position relative to
			-- beginning of stream
			-- (from ECOM_STREAM_SEEK)
	
feature -- Comparison

	frozen deep_equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		ensure -- from ANY
			shallow_implies_deep: standard_equal (some, other) implies Result
			both_or_none_void: (some = Void) implies (Result = (other = Void))
			same_type: (Result and (some /= Void)) implies (other /= Void and then some.same_type (other))
			symmetric: Result implies deep_equal (other, some)

	frozen equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

	frozen is_deep_equal (other: ECOM_STREAM): BOOLEAN
			-- Are `Current' and `other' attached to isomorphic object structures?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		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)

	is_equal (other: ECOM_STREAM): BOOLEAN
			-- Is `other' attached to an object considered
			-- equal to current object?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			symmetric: Result implies other.is_equal (Current)
			consistent: standard_is_equal (other) implies Result

	frozen standard_equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

	frozen standard_is_equal (other: ECOM_STREAM): 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
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
	
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

	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
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))
	
feature -- Duplication

	copy (other: ECOM_STREAM)
			-- 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)
		ensure -- from ANY
			is_equal: is_equal (other)

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

	frozen deep_twin: ECOM_STREAM
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		ensure -- from ANY
			deep_twin_not_void: Result /= Void
			deep_equal: deep_equal (Current, Result)

	frozen standard_copy (other: ECOM_STREAM)
			-- 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)
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)

	frozen standard_twin: ECOM_STREAM
			-- New object field-by-field identical to `other'.
			-- Always uses default copying semantics.
			-- (from ANY)
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)

	frozen twin: ECOM_STREAM
			-- New object equal to `Current'
			-- twin calls copy; to change copying/twining semantics, redefine copy.
			-- (from ANY)
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result.is_equal (Current)
	
feature -- Basic operations

	frozen default: ?ECOM_STREAM
			-- Default value of object's type
			-- (from ANY)

	frozen default_pointer: POINTER
			-- Default value of type `POINTER'
			-- (Avoid the need to write `p'.default for
			-- some `p' of type `POINTER'.)
			-- (from ANY)

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

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)
	
feature -- Basic Operations

	clone_stream: ECOM_STREAM
			-- New stream referencing
			-- the same bytes as Current
			-- Seek pointer is also cloned
		ensure
			clone_created: Result /= Void and then Result.exists

	copy_to (destination: ECOM_STREAM; bytes: ECOM_ULARGE_INTEGER)
			-- Copy `bytes' number of bytes from current seek pointer
			-- in stream to current seek pointer in
			-- `destination'.
		require
			valid_destination: destination /= Void and then destination.exists
			valid_bytes_number: bytes /= Void and then bytes.exists

	finish
			-- Set seek pointer to end of stream.
		ensure
			at_end: end_of_stream

	lock_region (offset, count: ECOM_ULARGE_INTEGER; lock: INTEGER_32)
			-- Restricts access to range of bytes defined by
			-- `offset' and `count'.
		require
			valid_offset: offset /= Void and then offset.exists
			valid_count: count /= Void and then count.exists
			valid_lock: is_valid_lock (lock)

	read (buffer: POINTER; bytes: INTEGER_32)
			-- Reads `bytes' number of bytes from stream
			-- into `buffer' starting at current seek pointer.
		require
			valid_buffer: buffer /= default_pointer
			valid_bytes: bytes >= 0

	read_boolean
			-- Read boolean from stream.

	read_character
			-- Read character from stream.

	read_integer
			-- Read integer from stream.

	read_real
			-- Read real from stream.

	read_string
			-- Read string from stream.

	seek (displacement: ECOM_LARGE_INTEGER; origin: INTEGER_32)
			-- Move seek pointer by `displacement'
			-- relative to `origin'.
			-- See class ECOM_STREAM_SEEK for `origin' values.
		require
			non_void_displacement: displacement /= Void
			valid_displacement: displacement.exists
			valid_seek_origin: is_valid_seek (origin)

	set_size (new_size: ECOM_ULARGE_INTEGER)
			-- Change size of stream to `new_size'.
		require
			valid_new_size: new_size /= Void and then new_size.exists
		ensure
			size = new_size

	start
			-- Set seek pointer to beginning of stream.
		ensure
			not_end: not end_of_stream

	unlock_region (offset, count: ECOM_ULARGE_INTEGER; lock: INTEGER_32)
			-- Removes access restriction to range of bytes defined by
			-- `offset' and `count'.
		require
			valid_offset: offset /= Void and then offset.exists
			valid_count: count /= Void and then count.exists
			valid_lock: is_valid_lock (lock)

	update_end_of_stream
			-- Update value of end_of_stream.

	write (buffer: POINTER; bytes: INTEGER_32)
			-- Writes `bytes' number of bytes into stream
			-- starting at current seek pointer.
		require
			valid_buffer: buffer /= default_pointer

	write_boolean (boolean: BOOLEAN)
			-- Write `boolean' into stream.

	write_character (character: CHARACTER_8)
			-- Write `character' into stream.

	write_integer (integer: INTEGER_32)
			-- Write `integer' into stream.

	write_real (real: REAL_32)
			-- Write `real' into stream.

	write_string (string: STRING_8)
			-- Write `string' into stream.
		require
			string /= Void
	
feature -- Output

	io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)
		ensure -- from ANY
			io_not_void: Result /= Void

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

	print (some: ?ANY)
			-- Write terse external representation of `some'
			-- on standard output.
			-- (from ANY)

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

	operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
		ensure -- from ANY
			operating_environment_not_void: Result /= Void
	
invariant
		-- from ECOM_QUERIABLE
	queriable_invariant: initializer /= default_pointer and then exists

		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

indexing
	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
		Eiffel Software
		356 Storke Road, 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 ECOM_STREAM