factor/basis/xml/autoencoding/autoencoding.factor

85 lines
2.3 KiB
Factor

! Copyright (C) 2005, 2009 Daniel Ehrenberg
! See http://factorcode.org/license.txt for BSD license.
USING: kernel namespaces xml.name io.encodings.utf8 xml.elements
io.encodings.utf16 xml.tokenize xml.state math ascii sequences
io.encodings.string io.encodings combinators accessors
xml.data io.encodings.iana xml.errors ;
IN: xml.autoencoding
: decode-stream ( encoding -- )
spot get [ swap re-decode ] change-stream drop ;
: continue-make-tag ( str -- tag )
parse-name-starting middle-tag end-tag ;
: start-utf16le ( -- tag )
utf16le decode-stream
"?\0" expect
check instruct ;
: 10xxxxxx? ( ch -- ? )
-6 shift 3 bitand 2 = ;
: start<name ( ch -- tag )
! This is unfortunate, and exists for the corner case
! that the first letter of the document is < and second is
! not ASCII
ascii?
[ utf8 decode-stream next make-tag ] [
next
[ drop get-next 10xxxxxx? not ] take-until
get-char suffix utf8 decode
utf8 decode-stream next
continue-make-tag
] if ;
: prolog-encoding ( prolog -- )
encoding>> dup "UTF-16" =
[ drop ] [
dup name>encoding
[ decode-stream ] [ bad-encoding ] ?if
] if ;
: instruct-encoding ( instruct/prolog -- )
dup prolog?
[ prolog-encoding ]
[ drop utf8 decode-stream ] if ;
: go-utf8 ( -- )
check utf8 decode-stream next next ;
: start< ( -- tag )
! What if first letter of processing instruction is non-ASCII?
get-next {
{ 0 [ next next start-utf16le ] }
{ CHAR: ? [ go-utf8 instruct dup instruct-encoding ] }
{ CHAR: ! [ go-utf8 direct ] }
[ check start<name ]
} case ;
: skip-utf8-bom ( -- tag )
"\u0000bb\u0000bf" expect utf8 decode-stream
"<" expect check make-tag ;
: decode-expecting ( encoding string -- tag )
[ decode-stream next ] [ expect ] bi* check make-tag ;
: start-utf16be ( -- tag )
utf16be "<" decode-expecting ;
: skip-utf16le-bom ( -- tag )
utf16le "\u0000fe<" decode-expecting ;
: skip-utf16be-bom ( -- tag )
utf16be "\u0000ff<" decode-expecting ;
: start-document ( -- tag )
get-char {
{ CHAR: < [ start< ] }
{ 0 [ start-utf16be ] }
{ 0xEF [ skip-utf8-bom ] }
{ 0xFF [ skip-utf16le-bom ] }
{ 0xFE [ skip-utf16be-bom ] }
[ drop utf8 decode-stream check f ]
} case ;