racket/collects/ffi/objc.ss
2009-01-06 19:52:40 +00:00

562 lines
21 KiB
Scheme

#lang scheme/base
(require scheme/foreign
scheme/stxparam
(for-syntax scheme/base))
(unsafe!)
(define objc-lib (ffi-lib "libobjc"))
(define-syntax define-objc/private
(syntax-rules ()
[(_ id type)
(define-objc/private id id type)]
[(_ id c-id type)
(define id (get-ffi-obj 'c-id objc-lib type))]))
(define-syntax-rule (define-objc id type)
(begin
(provide* (unsafe id))
(define-objc/private id id type)))
;; ----------------------------------------
(provide _id _Class _BOOL _SEL _Ivar
make-objc_super _objc_super)
(define _id (_cpointer/null 'id))
(define _SEL (_cpointer/null 'SEL))
(define _Ivar (_cpointer/null 'Ivar))
(define _Class (make-ctype _id
(lambda (v) v)
(lambda (p)
(when p (cpointer-push-tag! p 'Class))
p)))
(define _BOOL (make-ctype _byte
(lambda (v) (if v 1 0))
(lambda (v) (not (eq? v 0)))))
(define _IMP (_fun _id _id -> _id))
(define-cstruct _objc_super ([receiver _id][class _Class]))
(provide YES NO)
(define YES #t)
(define NO #f)
;; ----------------------------------------
(define-objc objc_lookUpClass (_fun _string -> _Class))
(define-objc sel_registerName (_fun _string -> _SEL))
(define-objc objc_allocateClassPair (_fun _Class _string _long -> _Class))
(define-objc objc_registerClassPair (_fun _Class -> _void))
(define-objc object_getClass (_fun _id -> _Class))
(provide class_addMethod)
(define (class_addMethod cls sel imp ty enc)
((get-ffi-obj 'class_addMethod objc-lib (_fun _Class _SEL ty _string -> _BOOL))
cls sel imp enc))
(define-objc class_addIvar (_fun _Class _string _long _uint8 _string -> _BOOL))
(define-objc object_getInstanceVariable (_fun _id _string [p : (_ptr o _pointer)]
-> [ivar : _Ivar]
-> (values ivar p)))
(define-objc object_setInstanceVariable (_fun _id _string _pointer -> _Ivar))
(define-objc/private objc_msgSend _fpointer)
(define-objc/private objc_msgSend_fpret _fpointer)
(define-objc/private objc_msgSendSuper _fpointer)
(define objc_msgSendSuper_fpret objc_msgSendSuper) ; why no fpret variant?
(define (lookup-send types msgSends msgSend msgSend_fpret first-arg-type)
;; First type in `types' vector is the result type
(or (hash-ref msgSends types #f)
(let ([m (function-ptr (if (memq (ctype->layout (vector-ref types 0))
'(float double double*))
msgSend_fpret
msgSend)
(_cprocedure
(list* first-arg-type _SEL (cdr (vector->list types)))
(vector-ref types 0)))])
(hash-set! msgSends types m)
m)))
(define msgSends (make-hash))
(define (objc_msgSend/typed types)
(lookup-send types msgSends objc_msgSend objc_msgSend_fpret _id))
(provide* (unsafe objc_msgSend/typed))
(define msgSendSupers (make-hash))
(define (objc_msgSendSuper/typed types)
(lookup-send types msgSendSupers objc_msgSendSuper objc_msgSendSuper_fpret _pointer))
(provide* (unsafe objc_msgSendSuper/typed))
;; ----------------------------------------
(provide* (unsafe import-class))
(define-syntax (import-class stx)
(syntax-case stx ()
[(_ id)
(quasisyntax/loc stx
(define id (objc_lookUpClass #,(symbol->string (syntax-e #'id)))))]
[(_ id ...)
(syntax/loc stx (begin (import-class id) ...))]))
;; ----------------------------------------
;; iget-value and set-ivar! work only with fields that contain Scheme values
(provide* (unsafe get-ivar) (unsafe set-ivar!))
(define-for-syntax (check-ivar ivar stx)
(unless (identifier? ivar)
(raise-type-error #f
"expected an identifier for an instance-variable name"
stx
ivar)))
(define-syntax (get-ivar stx)
(syntax-case stx ()
[(_ obj ivar)
(begin
(check-ivar #'ivar stx)
(quasisyntax/loc stx
(get-ivar-value obj #,(symbol->string (syntax-e #'ivar)))))]))
(define (get-ivar-value obj name)
(let-values ([(ivar p) (object_getInstanceVariable obj name)])
(and p (ptr-ref p _scheme))))
(define-syntax (set-ivar! stx)
(syntax-case stx ()
[(_ obj ivar val)
(begin
(check-ivar #'ivar stx)
(quasisyntax/loc stx
(set-ivar-value obj #,(symbol->string (syntax-e #'ivar)) val)))]))
(define (set-ivar-value obj name val)
(let-values ([(ivar p) (object_getInstanceVariable obj name)])
(if p
(ptr-set! p _scheme val)
(let ([p (malloc-immobile-cell val)])
(void (object_setInstanceVariable obj name p))))))
(define (free-fields obj names)
(for-each (lambda (name)
(let-values ([(ivar p) (object_getInstanceVariable obj name)])
(when p (free-immobile-cell p))))
names))
;; ----------------------------------------
(define-for-syntax method-sels (make-hash))
(define-for-syntax (register-selector sym)
(or (hash-ref method-sels (cons (syntax-local-lift-context) sym) #f)
(let ([id (syntax-local-lift-expression
#`(sel_registerName #,(symbol->string sym)))])
(hash-set! method-sels sym id)
id)))
(provide* (unsafe selector))
(define-syntax (selector stx)
(syntax-case stx ()
[(_ id)
(begin
(unless (identifier? #'id)
(raise-syntax-error #f
"expected an identifier"
stx
#'id))
(register-selector (syntax-e #'id)))]))
;; ----------------------------------------
(define-for-syntax (combine stxes)
(string->symbol
(apply
string-append
(map (lambda (e) (symbol->string (syntax-e e)))
(syntax->list stxes)))))
(define-for-syntax (check-method-name m stx)
(unless (identifier? m)
(raise-syntax-error #f
"expected an identifier for the method name"
stx
m)))
(define-for-syntax (check-id-colon id stx)
(unless (regexp-match #rx":$" (symbol->string (syntax-e id)))
(raise-syntax-error #f
"expected an identifier that ends in `:' to tag an argument"
stx
id)))
(define-for-syntax (parse-arg-list l stx formals?)
(define (is-typed? l)
(if formals?
(and (pair? (cdr l))
(let ([l (syntax->list (cadr l))])
(and (list? l)
(= 2 (length l)))))
(and (pair? (cdr l))
(eq? '#:type (syntax-e (cadr l))))))
(let loop ([l l])
(if (null? l)
null
(begin
(unless (identifier? (car l))
(raise-syntax-error #f
"expected an identifier to tag an argument"
stx
(car l)))
(check-id-colon (car l) stx)
(let ([tag (car l)]
[type (if (is-typed? l)
(if formals?
(car (syntax-e (cadr l)))
(if (pair? (cddr l))
(caddr l)
(raise-syntax-error #f
"missing type expression after tag with #:type"
stx
(car l))))
#'_id)]
[rest (if formals?
(cdr l)
(if (is-typed? l)
(cdddr l)
(cdr l)))])
(unless (pair? rest)
(raise-syntax-error #f
(format "missing an argument~a after tag"
(if formals? " identifier" " expression"))
stx
tag))
(cons
(list tag type (let ([arg (car rest)])
(if formals?
(if (identifier? arg)
arg
(let ([l (syntax->list arg)])
(unless (and (list? l)
(= 2 (length l))
(identifier? (cadr l)))
(raise-syntax-error #f
(string-append
"exepected an identifier for an argument name"
" or a parenthesized type--identifier sequence")
stx
arg))
(cadr l)))
arg)))
(loop (cdr rest))))))))
(provide* (unsafe tell) (unsafe tellv))
(define-for-syntax (build-send stx result-type send/typed send-args l-stx)
(let ([l (syntax->list l-stx)])
(with-syntax ([((tag type arg) ...) (parse-arg-list l stx #f)]
[send send/typed]
[(send-arg ...) send-args])
(quasisyntax/loc stx
((send (type-vector #,result-type type ...))
send-arg ... #,(register-selector (combine #'(tag ...)))
arg ...)))))
(define-syntax (tell stx)
(syntax-case stx ()
[(_ target)
(raise-syntax-error #f
"method identifier missing"
stx)]
[(_ #:type t)
(raise-syntax-error #f
"method target object missing"
stx)]
[(_ #:type t target)
(raise-syntax-error #f
"method identifier missing"
stx)]
[(_ #:type t target method)
(let ([m #'method])
(check-method-name m stx)
(quasisyntax/loc stx
((objc_msgSend/typed (type-vector t)) target #,(register-selector (syntax-e m)))))]
[(_ target method)
(not (keyword? (syntax-e #'target)))
(let ([m #'method])
(check-method-name m stx)
(quasisyntax/loc stx
((objc_msgSend/typed (type-vector _id)) target #,(register-selector (syntax-e m)))))]
[(_ #:type result-type target method/arg ...)
(build-send stx #'result-type
#'objc_msgSend/typed #'(target)
#'(method/arg ...))]
[(_ target method/arg ...)
(build-send stx #'_id
#'objc_msgSend/typed #'(target)
#'(method/arg ...))]))
(define-syntax-rule (tellv a ...)
(tell #:type _void a ...))
(define-for-syntax liftable-type?
(let ([prims
(syntax->list #'(_id _Class _SEL _void _int _long _float _double _double* _BOOL))])
(lambda (t)
(and (identifier? t)
(ormap (lambda (p) (free-identifier=? t p))
prims)))))
(define-syntax (type-vector stx)
(let ([types (cdr (syntax->list stx))])
((if (andmap liftable-type? (cdr (syntax->list stx)))
(lambda (e)
(syntax-local-lift-expression #`(intern-type-vector #,e)))
values)
(quasisyntax/loc stx (vector . #,types)))))
(define type-vectors (make-hash))
(define (intern-type-vector v)
(or (hash-ref type-vectors v #f)
(begin
(hash-set! type-vectors v v)
v)))
;; ----------------------------------------
(provide* (unsafe define-objc-class) self super-tell)
(define-syntax (define-objc-class stx)
(syntax-case stx ()
[(_ id superclass (ivar ...) method ...)
(begin
(unless (identifier? #'id)
(raise-syntax-error #f
"expected an identifier for class definition"
stx
#'id))
(for-each (lambda (ivar)
(unless (identifier? ivar)
(raise-syntax-error #f
"expected an identifier for an instance variable"
stx
ivar)))
(syntax->list #'(ivar ...)))
(let ([ivars (syntax->list #'(ivar ...))]
[methods (syntax->list #'(method ...))])
(with-syntax ([id-str (symbol->string (syntax-e #'id))]
[whole-stx stx]
[(dealloc-method ...)
(if (null? ivars)
;; no need to override dealloc:
#'()
;; add dealloc if it's not here:
(if (ormap (lambda (m)
(syntax-case m ()
[(+/- result-type (id . _) . _)
(eq? (syntax-e #'id) 'dealloc)]))
methods)
;; Given a dealloc extension:
#'()
;; Need to add one explicitly:
#'((-a _void (dealloc) (void)))))])
(syntax/loc stx
(begin
(define superclass-id superclass)
(define id (objc_allocateClassPair superclass-id id-str 0))
(add-ivar id 'ivar) ...
(let-syntax ([ivar (make-ivar-form 'ivar)] ...)
(add-method whole-stx id superclass-id method) ...
(add-method whole-stx id superclass-id dealloc-method) ...
(void))
(objc_registerClassPair id))))))]))
(define-for-syntax (make-ivar-form sym)
(with-syntax ([sym sym])
(make-set!-transformer
(lambda (stx)
(syntax-case stx (set!)
[(set! _ val)
(syntax/loc stx (set-ivar! self sym val))]
[(_ arg ...)
(quasisyntax/loc stx (#,(quasisyntax/loc #'sym #'(get-ivar self sym))
arg ...))]
[_ (quasisyntax/loc #'sym (get-ivar self sym))])))))
(define (layout->string l)
(case l
[(uint8) "C"]
[(int8) "c"]
[(float) "f"]
[(double) "d"]
[(bool) "B"]
[(void) "v"]
[(bytes) "*"]
[(pointer fpointer string/ucs-4 string/utf-16) "?"]
[else
(cond
[(list? l)
(apply string-append
(for/list ([l (in-list l)]
[i (in-naturals)])
(format "f~a=~a" i (layout->string l))))]
[(eq? l (ctype->layout _int)) "i"]
[(eq? l (ctype->layout _uint)) "I"]
[(eq? l (ctype->layout _short)) "s"]
[(eq? l (ctype->layout _ushort)) "S"]
[(eq? l (ctype->layout _long)) "l"]
[(eq? l (ctype->layout _ulong)) "L"]
[else (error 'generate-layout "unknown layout: ~e" l)])]))
(define (generate-layout rt arg-types)
(let ([rl (ctype->layout rt)]
[al (map ctype->layout arg-types)])
(apply
string-append
(layout->string rl)
"@:"
(map layout->string al))))
(define-syntax-parameter self
(lambda (stx)
(raise-syntax-error #f
"valid only within a `define-objc-class' method"
stx)))
(define-syntax-parameter super-class
(lambda (stx) #f))
(define-syntax-parameter super-tell
(lambda (stx)
(raise-syntax-error #f
"valid only within a `define-objc-class' method"
stx)))
(define-for-syntax (make-id-stx orig-id)
(make-set!-transformer
(lambda (stx)
(syntax-case stx (set!)
[(set! id v) (raise-syntax-error #f
"assignment to self identifier disallowed"
stx)]
[(id arg ...) (quasisyntax/loc stx (#,orig-id arg ...))]
[id (datum->syntax orig-id (syntax-e orig-id) stx orig-id orig-id)]))))
(define-syntax (add-method stx)
(syntax-case stx ()
[(_ whole-stx cls superclass-id m)
(let ([stx #'whole-stx])
(syntax-case #'m ()
[(kind result-type (id arg ...) body0 body ...)
(or (free-identifier=? #'kind #'+)
(free-identifier=? #'kind #'-)
(free-identifier=? #'kind #'+a)
(free-identifier=? #'kind #'-a))
(let ([id #'id]
[args (syntax->list #'(arg ...))]
[in-class? (or (free-identifier=? #'kind #'+)
(free-identifier=? #'kind #'+a))])
(when (null? args)
(unless (identifier? id)
(raise-syntax-error #f
"expected an identifier for method name"
stx
id)))
(with-syntax ([((arg-tag arg-type arg-id) ...)
(if (null? args)
null
(parse-arg-list (cons id args) stx #t))])
(with-syntax ([id-str (if (null? args)
(symbol->string (syntax-e id))
(symbol->string (combine #'(arg-tag ...))))]
[(dealloc-body ...)
(if (eq? (syntax-e id) 'dealloc)
(syntax-case stx ()
[(_ _ _ [ivar ...] . _)
(with-syntax ([(ivar-str ...)
(map (lambda (ivar)
(symbol->string (syntax-e ivar)))
(syntax->list #'(ivar ...)))])
#'((free-fields self '(ivar-str ...))
(super-tell #:type _void dealloc)))]
[_ (error "oops")])
'())]
[in-cls (if in-class?
#'(object_getClass cls)
#'cls)]
[atomic? (or (free-identifier=? #'kind #'+a)
(free-identifier=? #'kind #'-a))])
(syntax/loc stx
(let ([rt result-type]
[arg-id arg-type] ...)
(void (class_addMethod in-cls
(sel_registerName id-str)
(save-method!
(lambda (self-id cmd arg-id ...)
(syntax-parameterize ([self (make-id-stx #'self-id)]
[super-class (make-id-stx #'superclass-id)]
[super-tell do-super-tell])
body0 body ...
dealloc-body ...)))
(_fun #:atomic? atomic? _id _id arg-type ... -> rt)
(generate-layout rt (list arg-id ...)))))))))]
[else (raise-syntax-error #f
"bad method form"
stx
#'m)]))]))
(define methods (make-hasheq))
(define (save-method! m)
;; Methods are never GCed, since classes are never unregistered
(hash-set! methods m #t)
m)
(define (add-ivar cls name)
(void (class_addIvar cls
(symbol->string name)
(ctype-sizeof _pointer)
(sub1 (integer-length (ctype-alignof _pointer)))
(layout->string (ctype->layout _pointer)))))
(define-for-syntax (do-super-tell stx)
(syntax-case stx ()
[(_ #:type t)
(raise-syntax-error #f
"method name missing"
stx)]
[(_ #:type t method)
(let ([m #'method])
(check-method-name m stx)
(quasisyntax/loc stx
((objc_msgSendSuper/typed (type-vector t))
(make-objc_super self super-class)
#,(register-selector (syntax-e m)))))]
[(_ method)
(not (keyword? (syntax-e #'method)))
(let ([m #'method])
(check-method-name m stx)
(quasisyntax/loc stx
((objc_msgSendSuper/typed (type-vector _id))
(make-objc_super self super-class)
#,(register-selector (syntax-e m)))))]
[(_ #:type result-type method/arg ...)
(build-send stx #'result-type
#'objc_msgSendSuper/typed
#'((make-objc_super self super-class))
#'(method/arg ...))]
[(_ method/arg ...)
(build-send stx #'_id
#'objc_msgSendSuper/typed
#'((make-objc_super self super-class))
#'(method/arg ...))]))
;; --------------------------------------------------
(define-unsafer objc-unsafe!)