1509 lines
66 KiB
Racket
1509 lines
66 KiB
Racket
#lang racket/base
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;; Foreign Racket interface
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(require '#%foreign setup/dirs racket/unsafe/ops
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(for-syntax racket/base racket/list syntax/stx
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racket/struct-info))
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(provide ctype-sizeof ctype-alignof compiler-sizeof
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malloc free end-stubborn-change
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cpointer? ptr-equal? ptr-add ptr-ref ptr-set! (protect-out cast)
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ptr-offset ptr-add! offset-ptr? set-ptr-offset!
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vector->cpointer flvector->cpointer saved-errno lookup-errno
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ctype? make-ctype make-cstruct-type make-sized-byte-string ctype->layout
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_void _int8 _uint8 _int16 _uint16 _int32 _uint32 _int64 _uint64
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_fixint _ufixint _fixnum _ufixnum
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_float _double _double*
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_bool _pointer _gcpointer _scheme (rename-out [_scheme _racket]) _fpointer function-ptr
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memcpy memmove memset
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malloc-immobile-cell free-immobile-cell
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make-late-weak-box make-late-weak-hasheq)
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(define-syntax define*
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(syntax-rules ()
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[(_ (name . args) body ...)
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(begin (provide name) (define (name . args) body ...))]
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[(_ name expr)
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(begin (provide name) (define name expr))]))
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;; ----------------------------------------------------------------------------
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;; C integer types
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(define* _sint8 _int8)
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(define* _sint16 _int16)
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(define* _sint32 _int32)
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(define* _sint64 _int64)
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;; _byte etc is a convenient name for _uint8 & _sint8
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;; (_byte is unsigned)
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(define* _byte _uint8)
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(define* _ubyte _uint8)
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(define* _sbyte _int8)
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;; _word etc is a convenient name for _uint16 & _sint16
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;; (_word is unsigned)
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(define* _word _uint16)
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(define* _uword _uint16)
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(define* _sword _int16)
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;; utility for the next few definitions
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(define (sizeof->3ints c-type)
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(case (compiler-sizeof c-type)
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[(2) (values _int16 _uint16 _int16)]
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[(4) (values _int32 _uint32 _int32)]
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[(8) (values _int64 _uint64 _int64)]
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[else (error 'foreign "internal error: bad compiler size for `~s'"
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c-type)]))
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;; _short etc is a convenient name for whatever is the compiler's `short'
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;; (_short is signed)
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(provide _short _ushort _sshort)
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(define-values (_short _ushort _sshort) (sizeof->3ints 'short))
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;; _int etc is a convenient name for whatever is the compiler's `int'
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;; (_int is signed)
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(provide _int _uint _sint)
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(define-values (_int _uint _sint) (sizeof->3ints 'int))
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;; _long etc is a convenient name for whatever is the compiler's `long'
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;; (_long is signed)
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(provide _long _ulong _slong)
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(define-values (_long _ulong _slong) (sizeof->3ints 'long))
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;; _llong etc is a convenient name for whatever is the compiler's `long long'
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;; (_llong is signed)
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(provide _llong _ullong _sllong)
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(define-values (_llong _ullong _sllong) (sizeof->3ints '(long long)))
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;; _intptr etc is a convenient name for whatever is the integer
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;; equivalent of the compiler's pointer (see `intptr_t') (_intptr is
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;; signed)
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(provide _intptr _uintptr _sintptr)
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(define-values (_intptr _uintptr _sintptr) (sizeof->3ints '(void *)))
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;; ----------------------------------------------------------------------------
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;; Getting and setting library objects
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(define lib-suffix (bytes->string/latin-1 (subbytes (system-type 'so-suffix) 1)))
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(define lib-suffix-re (regexp (string-append "\\." lib-suffix "$")))
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(define suffix-before-version? (not (equal? lib-suffix "dylib")))
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(provide (protect-out (rename-out [get-ffi-lib ffi-lib]))
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ffi-lib? ffi-lib-name)
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(define get-ffi-lib
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(case-lambda
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[(name) (get-ffi-lib name "")]
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[(name version/s)
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(cond
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[(not name) (ffi-lib name)] ; #f => NULL => open this executable
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[(not (or (string? name) (path? name)))
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(raise-type-error 'ffi-lib "library-name" name)]
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[else
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;; A possible way that this might be misleading: say that there is a
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;; "foo.so" file in the current directory, which refers to some
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;; undefined symbol, trying to use this function with "foo.so" will try
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;; a dlopen with "foo.so" which isn't found, then it tries a dlopen with
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;; "/<curpath>/foo.so" which fails because of the undefined symbol, and
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;; since all fails, it will use (ffi-lib "foo.so") to raise the original
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;; file-not-found error. This is because the dlopen doesn't provide a
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;; way to distinguish different errors (only dlerror, but that's
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;; unreliable).
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(let* ([versions (if (list? version/s) version/s (list version/s))]
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[versions (map (lambda (v)
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(if (or (not v) (zero? (string-length v)))
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"" (string-append "." v)))
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versions)]
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[fullpath (lambda (p) (path->complete-path (cleanse-path p)))]
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[absolute? (absolute-path? name)]
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[name0 (path->string (cleanse-path name))] ; orig name
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[names (map (if (regexp-match lib-suffix-re name0) ; name+suffix
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(lambda (v) (string-append name0 v))
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(lambda (v)
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(if suffix-before-version?
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(string-append name0 "." lib-suffix v)
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(string-append name0 v "." lib-suffix))))
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versions)]
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[ffi-lib* (lambda (name) (ffi-lib name #t))])
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(or ;; try to look in our library paths first
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(and (not absolute?)
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(ormap (lambda (dir)
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;; try good names first, then original
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(or (ormap (lambda (name)
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(ffi-lib* (build-path dir name)))
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names)
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(ffi-lib* (build-path dir name0))))
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(get-lib-search-dirs)))
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;; try a system search
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(ormap ffi-lib* names) ; try good names first
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(ffi-lib* name0) ; try original
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(ormap (lambda (name) ; try relative paths
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(and (file-exists? name) (ffi-lib* (fullpath name))))
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names)
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(and (file-exists? name0) ; relative with original
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(ffi-lib* (fullpath name0)))
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;; give up: call ffi-lib so it will raise an error
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(ffi-lib (car names))))])]))
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(define (get-ffi-lib-internal x)
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(if (ffi-lib? x) x (get-ffi-lib x)))
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;; These internal functions provide the functionality to be used by
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;; get-ffi-obj, set-ffi-obj! and define-c below
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(define (ffi-get ffi-obj type)
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(ptr-ref ffi-obj type))
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(define (ffi-set! ffi-obj type new)
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(let-values ([(new type) (get-lowlevel-object new type)])
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(hash-set! ffi-objects-ref-table ffi-obj new)
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(ptr-set! ffi-obj type new)))
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;; This is better handled with `make-c-parameter'
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(provide (protect-out ffi-obj-ref))
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(define ffi-obj-ref
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(case-lambda
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[(name lib) (ffi-obj-ref name lib #f)]
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[(name lib failure)
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(let ([name (get-ffi-obj-name 'ffi-obj-ref name)]
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[lib (get-ffi-lib-internal lib)])
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(with-handlers ([exn:fail:filesystem?
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(lambda (e) (if failure (failure) (raise e)))])
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(ffi-obj name lib)))]))
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;; get-ffi-obj is implemented as a syntax only to be able to propagate the
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;; foreign name into the type syntax, which allows generated wrappers to have a
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;; proper name.
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(provide (protect-out get-ffi-obj))
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(define get-ffi-obj*
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(case-lambda
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[(name lib type) (get-ffi-obj* name lib type #f)]
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[(name lib type failure)
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(let ([name (get-ffi-obj-name 'get-ffi-obj name)]
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[lib (get-ffi-lib-internal lib)])
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(let-values ([(obj error?)
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(with-handlers
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([exn:fail:filesystem?
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(lambda (e)
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(if failure (values (failure) #t) (raise e)))])
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(values (ffi-obj name lib) #f))])
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(if error? obj (ffi-get obj type))))]))
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(define-syntax (get-ffi-obj stx)
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(syntax-case stx ()
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[(_ name lib type)
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#`(get-ffi-obj* name lib #,(syntax-property #`type 'ffi-name #'name))]
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[(_ name lib type failure)
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#`(get-ffi-obj* name lib #,(syntax-property #`type 'ffi-name #'name)
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failure)]
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[x (identifier? #'x) #'get-ffi-obj*]))
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;; It is important to use the set-ffi-obj! wrapper because it takes care of
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;; keeping a handle on the object -- otherwise, setting a callback hook will
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;; crash when the Scheme function is gone.
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(provide (protect-out set-ffi-obj!))
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(define (set-ffi-obj! name lib type new)
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(ffi-set! (ffi-obj (get-ffi-obj-name 'set-ffi-obj! name)
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(get-ffi-lib-internal lib))
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type new))
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;; Combining the above two in a `define-c' special form which makes a Scheme
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;; `binding', first a `parameter'-like constructor:
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(provide (protect-out make-c-parameter))
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(define (make-c-parameter name lib type)
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(let ([obj (ffi-obj (get-ffi-obj-name 'make-c-parameter name)
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(get-ffi-lib-internal lib))])
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(case-lambda [() (ffi-get obj type)]
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[(new) (ffi-set! obj type new)])))
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;; Then the fake binding syntax, uses the defined identifier to name the
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;; object:
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(provide (protect-out define-c))
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(define-syntax (define-c stx)
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(syntax-case stx ()
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[(_ var-name lib-name type-expr)
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(with-syntax ([(p) (generate-temporaries (list #'var-name))])
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(namespace-syntax-introduce
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#'(begin (define p (make-c-parameter 'var-name lib-name type-expr))
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(define-syntax var-name
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(syntax-id-rules (set!)
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[(set! var val) (p val)]
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[(var . xs) ((p) . xs)]
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[var (p)])))))]))
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;; Used to convert strings and symbols to a byte-string that names an object
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(define (get-ffi-obj-name who objname)
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(cond [(bytes? objname) objname]
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[(symbol? objname) (get-ffi-obj-name who (symbol->string objname))]
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[(string? objname) (string->bytes/utf-8 objname)]
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[else (raise-type-error who "object-name" objname)]))
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;; This table keeps references to values that are set in foreign libraries, to
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;; avoid them being GCed. See set-ffi-obj! above.
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(define ffi-objects-ref-table (make-hasheq))
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;; ----------------------------------------------------------------------------
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;; Compile-time support for fun-expanders
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(begin-for-syntax
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;; The `_fun' macro tears its input apart and reassemble it using pieces from
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;; custom function types (macros). This whole deal needs some work to make
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;; it play nicely with code certificates, so Matthew wrote the following
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;; code. The idea is to create a define-fun-syntax which makes the new
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;; syntax transformer be an object that carries extra information, later used
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;; by `expand-fun-syntax/fun'.
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(define fun-cert-key (gensym))
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;; bug in begin-for-syntax (PR7104), see below
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(define foo!!! (make-parameter #f))
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(define (expand-fun-syntax/normal fun-stx stx)
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((foo!!!) fun-stx stx))
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(define-values (make-fun-syntax fun-syntax?
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fun-syntax-proc fun-syntax-certifier fun-syntax-name)
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(let-values ([(desc make pred? get set!)
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(make-struct-type
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'fun-syntax #f 3 0 #f '() (current-inspector)
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expand-fun-syntax/normal)])
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(values make pred?
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(make-struct-field-accessor get 0 'proc)
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(make-struct-field-accessor get 1 'certifier)
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(make-struct-field-accessor get 2 'name))))
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;; This is used to expand a fun-syntax in a _fun type context.
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(define (expand-fun-syntax/fun stx)
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(let loop ([stx stx])
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(define (do-expand id id?) ; id? == are we expanding an identifier?
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(define v (syntax-local-value id (lambda () #f)))
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(define set!-trans? (set!-transformer? v))
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(define proc (if set!-trans? (set!-transformer-procedure v) v))
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(if (and (fun-syntax? proc) (or (not id?) set!-trans?))
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;; Do essentially the same thing that `local-expand' does.
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;; First, create an "introducer" to mark introduced identifiers:
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(let* ([introduce (make-syntax-introducer)]
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[expanded
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;; Re-introduce mark related to expansion of `_fun':
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(syntax-local-introduce
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;; Re-add mark specific to this expansion, cancelling
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;; some marks applied before expanding (leaving only
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;; introuced syntax marked)
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(introduce
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;; Actually expand:
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((fun-syntax-proc proc)
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;; Add mark specific to this expansion:
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(introduce
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;; Remove mark related to expansion of `_fun':
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(syntax-local-introduce stx)))))])
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;; Certify based on definition of expander, then loop
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;; to continue expanding:
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(loop ((fun-syntax-certifier proc)
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expanded fun-cert-key introduce)))
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stx))
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(syntax-case stx ()
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[(id . rest) (identifier? #'id) (do-expand #'id #f)]
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[id (identifier? #'id) (do-expand #'id #t)]
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[_else stx])))
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;; Use module-or-top-identifier=? because we use keywords like `=' and want
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;; to make it possible to play with it at the toplevel.
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(define id=? module-or-top-identifier=?)
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(define (split-by key args)
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(let loop ([args args] [r (list '())])
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(cond [(null? args) (reverse (map reverse r))]
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[(eq? key (car args)) (loop (cdr args) (cons '() r))]
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[else (loop (cdr args)
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(cons (cons (car args) (car r)) (cdr r)))])))
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(define (add-renamer body from to)
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(with-syntax ([body body] [from from] [to to])
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#'(let-syntax ([to (syntax-id-rules ()
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[(_?_ . _rest_) (from . _rest_)] [_?_ from])])
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body)))
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(define (custom-type->keys type err)
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(define stops (map (lambda (s) (datum->syntax type s #f))
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'(#%app #%top #%datum)))
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;; Expand `type' using expand-fun-syntax/fun
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(define orig (expand-fun-syntax/fun type))
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(define (with-arg x)
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(syntax-case* x (=>) id=?
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[(id => body) (identifier? #'id)
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;; Extract #'body from its context, use a key it needs certification:
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(list (syntax-recertify #'id orig #f fun-cert-key)
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(syntax-recertify #'body orig #f fun-cert-key))]
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[_else x]))
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(define (cert-id id)
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(syntax-recertify id orig #f fun-cert-key))
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(let ([keys '()])
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(define (setkey! key val . id?)
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(cond
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[(assq key keys)
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(err "bad expansion of custom type (two `~a:'s)" key type)]
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[(and (pair? id?) (car id?) (not (identifier? val)))
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(err "bad expansion of custom type (`~a:' expects an identifier)"
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key type)]
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[else (set! keys (cons (cons key val) keys))]))
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(let loop ([t orig])
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(define (next rest . args) (apply setkey! args) (loop rest))
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(syntax-case* t
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(type: expr: bind: 1st-arg: prev-arg: pre: post: keywords: =>)
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id=?
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[(type: t x ...) (next #'(x ...) 'type #'t)]
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[(expr: e x ...) (next #'(x ...) 'expr #'e)]
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[(bind: id x ...) (next #'(x ...) 'bind (cert-id #'id) #t)]
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[(1st-arg: id x ...) (next #'(x ...) '1st (cert-id #'id) #t)]
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[(prev-arg: id x ...) (next #'(x ...) 'prev (cert-id #'id) #t)]
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;; in the following two cases pass along orig for recertifying
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;; first explicitly check if the `(id => expr)' form left off
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;; the parentheses
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[(pre: p => expr x ...) (err "bad form for `pre:'. Expected either `pre: (id => expression)' or `pre: expression'" #'(pre: p => expr))]
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[(pre: p x ...) (next #'(x ...) 'pre (with-arg #'p))]
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[(post: p => expr x ...) (err "bad form for `post:' Expected either `post: (id => expression)' or `post: expression'" #'(post: p => expr))]
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[(post: p x ...) (next #'(x ...) 'post (with-arg #'p))]
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[(keywords: x ...)
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(let kloop ([ks '()] [xs #'(x ...)])
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(syntax-case xs ()
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[(k v x ...) (syntax-e #'k)
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(kloop (cons (cons (syntax-e #'k) #'v) ks) #'(x ...))]
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[_ (next xs 'keywords (reverse ks))]))]
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[() (and (pair? keys) keys)]
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[_else #f]))))
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;; This is used for a normal expansion of fun-syntax, when not in a _fun type
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;; context.
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;; bug in begin-for-syntax (PR7104), see above
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;; should be (define (expand-fun-syntax/normal fun-stx stx) ...)
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(foo!!! (lambda (fun-stx stx)
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(define (err msg . sub)
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(apply raise-syntax-error (fun-syntax-name fun-stx) msg stx sub))
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(let ([keys (custom-type->keys stx err)])
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(define (getkey key) (cond [(assq key keys) => cdr] [else #f]))
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(define (notkey key)
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(when (getkey key)
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(err (format "this type must be used in a _fun expression (uses ~s)"
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key))))
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(if keys
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(let ([type (getkey 'type)] [pre (getkey 'pre)] [post (getkey 'post)])
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(unless type
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(err "this type must be used in a _fun expression (#f type)"))
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(for-each notkey '(expr bind 1st prev keywords))
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(if (or pre post)
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;; a type with pre/post blocks
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(let ([make-> (lambda (x what)
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(cond [(not x) #'#f]
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[(and (list? x) (= 2 (length x))
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(identifier? (car x)))
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#`(lambda (#,(car x)) #,(cadr x))]
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[else #`(lambda (_)
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(error '#,(fun-syntax-name fun-stx)
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"cannot be used to ~a"
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#,what))]))])
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(with-syntax ([type type]
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[scheme->c (make-> pre "send values to C")]
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[c->scheme (make-> post "get values from C")])
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#'(make-ctype type scheme->c c->scheme)))
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;; simple type
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type))
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;; no keys => normal expansion
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((fun-syntax-proc fun-stx) stx))))))
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;; Use define-fun-syntax instead of define-syntax for forms that
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;; are to be expanded by `_fun':
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(provide define-fun-syntax)
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(define-syntax define-fun-syntax
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(syntax-rules ()
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[(_ id trans)
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(define-syntax id
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(let* ([xformer trans]
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[set!-trans? (set!-transformer? xformer)])
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(unless (or (and (procedure? xformer)
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(procedure-arity-includes? xformer 1))
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|
set!-trans?)
|
|
(raise-type-error 'define-fun-syntax
|
|
"procedure (arity 1) or set!-transformer"
|
|
xformer))
|
|
(let ([f (make-fun-syntax (if set!-trans?
|
|
(set!-transformer-procedure xformer)
|
|
xformer)
|
|
;; Capture definition-time certificates:
|
|
(syntax-local-certifier)
|
|
'id)])
|
|
(if set!-trans? (make-set!-transformer f) f))))]))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Function type
|
|
|
|
;; Creates a simple function type that can be used for callouts and callbacks,
|
|
;; optionally applying a wrapper function to modify the result primitive
|
|
;; (callouts) or the input procedure (callbacks).
|
|
(define* (_cprocedure itypes otype
|
|
#:abi [abi #f]
|
|
#:wrapper [wrapper #f]
|
|
#:keep [keep #t]
|
|
#:atomic? [atomic? #f]
|
|
#:async-apply [async-apply #f]
|
|
#:save-errno [errno #f])
|
|
(_cprocedure* itypes otype abi wrapper keep atomic? async-apply errno))
|
|
|
|
;; for internal use
|
|
(define held-callbacks (make-weak-hasheq))
|
|
(define (_cprocedure* itypes otype abi wrapper keep atomic? async-apply errno)
|
|
(define-syntax-rule (make-it wrap)
|
|
(make-ctype _fpointer
|
|
(lambda (x)
|
|
(and x
|
|
(let ([cb (ffi-callback (wrap x) itypes otype abi atomic? async-apply)])
|
|
(cond [(eq? keep #t) (hash-set! held-callbacks x cb)]
|
|
[(box? keep)
|
|
(let ([x (unbox keep)])
|
|
(set-box! keep
|
|
(if (or (null? x) (pair? x)) (cons cb x) cb)))]
|
|
[(procedure? keep) (keep cb)])
|
|
cb)))
|
|
(lambda (x) (and x (wrap (ffi-call x itypes otype abi errno))))))
|
|
(if wrapper (make-it wrapper) (make-it begin)))
|
|
|
|
;; Syntax for the special _fun type:
|
|
;; (_fun [{(name ... [. name]) | name} [-> expr] ::]
|
|
;; {type | (name : type [= expr]) | ([name :] type = expr)} ...
|
|
;; -> {type | (name : type)}
|
|
;; [-> expr])
|
|
;; Usage:
|
|
;; `{(name ...) | ...} ::' specify explicit wrapper function formal arguments
|
|
;; `-> expr' can be used instead of the last expr
|
|
;; `type' input type (implies input, but see type macros next)
|
|
;; `(name : type = expr)' specify name and type, `= expr' means computed input
|
|
;; `-> type' output type (possibly with name)
|
|
;; `-> expr' specify different output, can use previous names
|
|
;; Also, see below for custom function types.
|
|
|
|
(provide ->) ; to signal better errors when trying to use this with contracts
|
|
(define-syntax (-> stx)
|
|
(raise-syntax-error '-> "should be used only in a _fun context" stx))
|
|
|
|
(provide _fun)
|
|
(define-for-syntax _fun-keywords
|
|
`([#:abi ,#'#f] [#:keep ,#'#t] [#:atomic? ,#'#f] [#:async-apply ,#'#f] [#:save-errno ,#'#f]))
|
|
(define-syntax (_fun stx)
|
|
(define (err msg . sub) (apply raise-syntax-error '_fun msg stx sub))
|
|
(define xs #f)
|
|
(define inputs #f)
|
|
(define output #f)
|
|
(define bind '())
|
|
(define pre '())
|
|
(define post '())
|
|
(define input-names #f)
|
|
(define output-type #f)
|
|
(define output-expr #f)
|
|
(define 1st-arg #f)
|
|
(define prev-arg #f)
|
|
(define (bind! x) (set! bind (append bind (list x))))
|
|
(define (pre! x) (set! pre (append pre (list x))))
|
|
(define (post! x) (set! post (append post (list x))))
|
|
(define-values (kwd-ref kwd-set!)
|
|
(let ([ks '()])
|
|
(values
|
|
(lambda (k)
|
|
(cond [(assq k ks) => cdr]
|
|
[(assq k _fun-keywords) => cadr]
|
|
[else (error '_fun "internal error: unknown keyword: ~.s" k)]))
|
|
(lambda (k-stx v [sub k-stx])
|
|
(let ([k (if (syntax? k-stx) (syntax-e k-stx) k-stx)])
|
|
(cond [(assq k ks)
|
|
(err (if (keyword? k-stx)
|
|
(format "indirectly duplicate ~s keyword" k-stx)
|
|
"duplicate keyword")
|
|
sub)]
|
|
[(assq k _fun-keywords) (set! ks (cons (cons k v) ks))]
|
|
[else (err "unknown keyword" sub)]))))))
|
|
(define ((t-n-e clause) type name expr)
|
|
(let ([keys (custom-type->keys type err)])
|
|
(define (getkey key) (cond [(assq key keys) => cdr] [else #f]))
|
|
(define (arg x . no-expr?)
|
|
(define use-expr?
|
|
(and (list? x) (= 2 (length x)) (identifier? (car x))))
|
|
;; when the current expr is not used with a (x => ...) form,
|
|
;; either check that no expression is given or just make it
|
|
;; disappear from the inputs.
|
|
(unless use-expr?
|
|
(if (and (pair? no-expr?) (car no-expr?) expr)
|
|
(err "got an expression for a custom type that do not use it"
|
|
clause)
|
|
(set! expr (void))))
|
|
(set! x (if use-expr? (add-renamer (cadr x) name (car x)) x))
|
|
(cond [(getkey '1st) =>
|
|
(lambda (v)
|
|
(if 1st-arg
|
|
(set! x (add-renamer x 1st-arg v))
|
|
(err "got a custom type that wants 1st arg too early"
|
|
clause)))])
|
|
(cond [(getkey 'prev) =>
|
|
(lambda (v)
|
|
(if prev-arg
|
|
(set! x (add-renamer x prev-arg v))
|
|
(err "got a custom type that wants prev arg too early"
|
|
clause)))])
|
|
x)
|
|
(when keys
|
|
(set! type (getkey 'type))
|
|
(cond [(and (not expr) (getkey 'expr)) => (lambda (x) (set! expr x))])
|
|
(cond [(getkey 'bind) => (lambda (x) (bind! #`[#,x #,name]))])
|
|
(cond [(getkey 'pre ) => (lambda (x) (pre! #`[#,name #,(arg x #t)]))])
|
|
(cond [(getkey 'post) => (lambda (x) (post! #`[#,name #,(arg x)]))])
|
|
(cond [(getkey 'keywords)
|
|
=> (lambda (ks)
|
|
(for ([k+v (in-list ks)])
|
|
(kwd-set! (car k+v) (cdr k+v) clause)))]))
|
|
;; turn a #f syntax to #f
|
|
(set! type (and type (syntax-case type () [#f #f] [_ type])))
|
|
(when type ; remember these for later usages
|
|
(unless 1st-arg (set! 1st-arg name))
|
|
(set! prev-arg name))
|
|
(list type name expr)))
|
|
(define (do-fun)
|
|
;; parse keywords
|
|
(let loop ()
|
|
(let ([k (and (pair? xs) (pair? (cdr xs)) (car xs))])
|
|
(when (and (syntax? k)
|
|
(keyword? (syntax-e k)))
|
|
(kwd-set! k (cadr xs))
|
|
(set! xs (cddr xs))
|
|
(loop))))
|
|
;; parse known punctuation
|
|
(set! xs (map (lambda (x)
|
|
(syntax-case* x (-> ::) id=? [:: '::] [-> '->] [_ x]))
|
|
xs))
|
|
;; parse "::"
|
|
(let ([s (split-by ':: xs)])
|
|
(case (length s)
|
|
[(0) (err "something bad happened (::)")]
|
|
[(1) (void)]
|
|
[(2) (if (and (= 1 (length (car s))) (not (eq? '-> (caar s))))
|
|
(begin (set! xs (cadr s)) (set! input-names (caar s)))
|
|
(err "bad wrapper formals"))]
|
|
[else (err "saw two or more instances of `::'")]))
|
|
;; parse "->"
|
|
(let ([s (split-by '-> xs)])
|
|
(case (length s)
|
|
[(0) (err "something bad happened (->)")]
|
|
[(1) (err "missing output type")]
|
|
[(2 3) (set! inputs (car s))
|
|
(case (length (cadr s))
|
|
[(1) (set! output-type (caadr s))]
|
|
[(0) (err "missing output type after `->'")]
|
|
[else (err "extraneous output type" (cadadr s))])
|
|
(unless (null? (cddr s))
|
|
(case (length (caddr s))
|
|
[(1) (set! output-expr (caaddr s))]
|
|
[(0) (err "missing output expression after `->'")]
|
|
[else (err "extraneous output expression"
|
|
(cadr (caddr s)))]))]
|
|
[else (err "saw three or more instances of `->'")]))
|
|
(set! inputs
|
|
(map (lambda (sub temp)
|
|
(let ([t-n-e (t-n-e sub)])
|
|
(syntax-case* sub (: =) id=?
|
|
[(name : type) (t-n-e #'type #'name #f)]
|
|
[(type = expr) (t-n-e #'type temp #'expr)]
|
|
[(name : type = expr) (t-n-e #'type #'name #'expr)]
|
|
[type (t-n-e #'type temp #f)])))
|
|
inputs
|
|
(generate-temporaries (map (lambda (x) 'tmp) inputs))))
|
|
;; when processing the output type, only the post code matters
|
|
(set! pre! (lambda (x) #f))
|
|
(set! output
|
|
(let ([temp (car (generate-temporaries #'(ret)))]
|
|
[t-n-e (t-n-e output-type)])
|
|
(syntax-case* output-type (: =) id=?
|
|
[(name : type) (t-n-e #'type #'name output-expr)]
|
|
[(type = expr) (if output-expr
|
|
(err "extraneous output expression" #'expr)
|
|
(t-n-e #'type temp #'expr))]
|
|
[(name : type = expr)
|
|
(if output-expr
|
|
(err "extraneous output expression" #'expr)
|
|
(t-n-e #'type #'name #'expr))]
|
|
[type (t-n-e #'type temp output-expr)])))
|
|
(let ([make-cprocedure
|
|
(lambda (wrapper)
|
|
#`(_cprocedure* (list #,@(filter-map car inputs))
|
|
#,(car output)
|
|
#,(kwd-ref '#:abi)
|
|
#,wrapper
|
|
#,(kwd-ref '#:keep)
|
|
#,(kwd-ref '#:atomic?)
|
|
#,(kwd-ref '#:async-apply)
|
|
#,(kwd-ref '#:save-errno)))])
|
|
(if (or (caddr output) input-names (ormap caddr inputs)
|
|
(ormap (lambda (x) (not (car x))) inputs)
|
|
(pair? bind) (pair? pre) (pair? post))
|
|
(let* ([input-names
|
|
(or input-names
|
|
(filter-map (lambda (i) (and (not (caddr i)) (cadr i)))
|
|
inputs))]
|
|
[output-expr
|
|
(let ([o (caddr output)])
|
|
(or (and (not (void? o)) o) (cadr output)))]
|
|
[args
|
|
(filter-map (lambda (i)
|
|
(and (caddr i)
|
|
(not (void? (caddr i)))
|
|
#`[#,(cadr i) #,(caddr i)]))
|
|
inputs)]
|
|
[ffi-args
|
|
(filter-map (lambda (x) (and (car x) (cadr x))) inputs)]
|
|
;; the actual wrapper body
|
|
[body (quasisyntax/loc stx
|
|
(lambda #,input-names
|
|
(let* (#,@args
|
|
#,@bind
|
|
#,@pre
|
|
[#,(cadr output) (ffi #,@ffi-args)]
|
|
#,@post)
|
|
#,output-expr)))]
|
|
;; if there is a string 'ffi-name property, use it as a name
|
|
[body (let ([n (cond [(syntax-property stx 'ffi-name)
|
|
=> syntax->datum]
|
|
[else #f])])
|
|
(if (string? n)
|
|
(syntax-property
|
|
body 'inferred-name
|
|
(string->symbol (string-append "ffi-wrapper:" n)))
|
|
body))])
|
|
(make-cprocedure #`(lambda (ffi) #,body)))
|
|
(make-cprocedure #'#f))))
|
|
(syntax-case stx ()
|
|
[(_ x ...) (begin (set! xs (syntax->list #'(x ...))) (do-fun))]))
|
|
|
|
(define (function-ptr p fun-ctype)
|
|
(if (or (cpointer? p) (procedure? p))
|
|
(if (eq? (ctype->layout fun-ctype) 'fpointer)
|
|
(if (procedure? p)
|
|
((ctype-scheme->c fun-ctype) p)
|
|
((ctype-c->scheme fun-ctype) p))
|
|
(raise-type-error 'function-ptr "function ctype" fun-ctype))
|
|
(raise-type-error 'function-ptr "cpointer" p)))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; String types
|
|
|
|
;; The internal _string type uses the native ucs-4 encoding, also providing a
|
|
;; utf-16 type
|
|
(provide _string/ucs-4 _string/utf-16)
|
|
|
|
;; 8-bit string encodings, #f is NULL
|
|
(define ((false-or-op op) x) (and x (op x)))
|
|
(define* _string/utf-8
|
|
(make-ctype _bytes
|
|
(false-or-op string->bytes/utf-8) (false-or-op bytes->string/utf-8)))
|
|
(define* _string/locale
|
|
(make-ctype _bytes
|
|
(false-or-op string->bytes/locale) (false-or-op bytes->string/locale)))
|
|
(define* _string/latin-1
|
|
(make-ctype _bytes
|
|
(false-or-op string->bytes/latin-1) (false-or-op bytes->string/latin-1)))
|
|
|
|
;; 8-bit string encodings, #f is NULL, can also use bytes and paths
|
|
(define ((any-string-op op) x)
|
|
(cond [(not x) x]
|
|
[(bytes? x) x]
|
|
[(path? x) (path->bytes x)]
|
|
[else (op x)]))
|
|
(define* _string*/utf-8
|
|
(make-ctype _bytes
|
|
(any-string-op string->bytes/utf-8) (false-or-op bytes->string/utf-8)))
|
|
(define* _string*/locale
|
|
(make-ctype _bytes
|
|
(any-string-op string->bytes/locale) (false-or-op bytes->string/locale)))
|
|
(define* _string*/latin-1
|
|
(make-ctype _bytes
|
|
(any-string-op string->bytes/latin-1) (false-or-op bytes->string/latin-1)))
|
|
|
|
;; A generic _string type that usually does the right thing via a parameter
|
|
(define* default-_string-type
|
|
(make-parameter _string*/utf-8
|
|
(lambda (x)
|
|
(if (ctype? x)
|
|
x (error 'default-_string-type "expecting a C type, got ~e" x)))))
|
|
;; The type looks like an identifier, but it's actually using the parameter
|
|
(provide _string)
|
|
(define-syntax _string
|
|
(syntax-id-rules ()
|
|
[(_ . xs) ((default-_string-type) . xs)]
|
|
[_ (default-_string-type)]))
|
|
|
|
;; _symbol is defined in C, since it uses simple C strings
|
|
(provide _symbol)
|
|
|
|
(provide _path)
|
|
;; `file' type: path-expands a path string, provide _path too.
|
|
(define* _file (make-ctype _path cleanse-path #f))
|
|
|
|
;; `string/eof' type: converts an output #f (NULL) to an eof-object.
|
|
(define string-type->string/eof-type
|
|
(let ([table (make-hasheq)])
|
|
(lambda (string-type)
|
|
(hash-ref table string-type
|
|
(lambda ()
|
|
(let ([new-type (make-ctype string-type
|
|
(lambda (x) (and (not (eof-object? x)) x))
|
|
(lambda (x) (or x eof)))])
|
|
(hash-set! table string-type new-type)
|
|
new-type))))))
|
|
(provide _string/eof _bytes/eof)
|
|
(define _bytes/eof
|
|
(make-ctype _bytes
|
|
(lambda (x) (and (not (eof-object? x)) x))
|
|
(lambda (x) (or x eof))))
|
|
(define-syntax _string/eof ; make it a syntax so it depends on the _string type
|
|
(syntax-id-rules ()
|
|
[(_ . xs) ((string-type->string/eof-type _string) . xs)]
|
|
[_ (string-type->string/eof-type _string)]))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Utility types
|
|
|
|
;; Call this with a name (symbol) and a list of symbols, where a symbol can be
|
|
;; followed by a '= and an integer to have a similar effect of C's enum.
|
|
(define (_enum name symbols [basetype _ufixint] #:unknown [unknown _enum])
|
|
(define sym->int '())
|
|
(define int->sym '())
|
|
(define s->c
|
|
(if name (string->symbol (format "enum:~a->int" name)) 'enum->int))
|
|
(define c->s
|
|
(if name (string->symbol (format "enum:int->~a" name)) 'int->enum))
|
|
(let loop ([i 0] [symbols symbols])
|
|
(unless (null? symbols)
|
|
(let-values ([(i rest) (if (and (pair? (cdr symbols))
|
|
(eq? '= (cadr symbols))
|
|
(pair? (cddr symbols)))
|
|
(values (caddr symbols) (cdddr symbols))
|
|
(values i (cdr symbols)))])
|
|
(set! sym->int (cons (cons (car symbols) i) sym->int))
|
|
(set! int->sym (cons (cons i (car symbols)) int->sym))
|
|
(loop (add1 i) rest))))
|
|
(make-ctype basetype
|
|
(lambda (x)
|
|
(let ([a (assq x sym->int)])
|
|
(if a
|
|
(cdr a)
|
|
(raise-type-error s->c (format "~a" (or name "enum")) x))))
|
|
(lambda (x)
|
|
(cond [(assq x int->sym) => cdr]
|
|
[(eq? unknown _enum)
|
|
(error c->s "expected a known ~a, got: ~s" basetype x)]
|
|
[(procedure? unknown) (unknown x)]
|
|
[else unknown]))))
|
|
|
|
;; Macro wrapper -- no need for a name
|
|
(provide (rename-out [_enum* _enum]))
|
|
(define-syntax (_enum* stx)
|
|
(syntax-case stx ()
|
|
[(_ x ...)
|
|
(with-syntax ([name (syntax-local-name)]) #'(_enum 'name x ...))]
|
|
[id (identifier? #'id) #'_enum]))
|
|
|
|
;; Call this with a name (symbol) and a list of (symbol int) or symbols like
|
|
;; the above with '= -- but the numbers have to be specified in some way. The
|
|
;; generated type will convert a list of these symbols into the logical-or of
|
|
;; their values and back.
|
|
(define (_bitmask name orig-symbols->integers . base?)
|
|
(define basetype (if (pair? base?) (car base?) _uint))
|
|
(define s->c
|
|
(if name (string->symbol (format "bitmask:~a->int" name)) 'bitmask->int))
|
|
(define symbols->integers
|
|
(let loop ([s->i orig-symbols->integers])
|
|
(cond
|
|
[(null? s->i)
|
|
null]
|
|
[(and (pair? (cdr s->i)) (eq? '= (cadr s->i)) (pair? (cddr s->i)))
|
|
(cons (list (car s->i) (caddr s->i))
|
|
(loop (cdddr s->i)))]
|
|
[(and (pair? (car s->i)) (pair? (cdar s->i)) (null? (cddar s->i))
|
|
(symbol? (caar s->i)) (integer? (cadar s->i)))
|
|
(cons (car s->i) (loop (cdr s->i)))]
|
|
[else
|
|
(error '_bitmask "bad spec in ~e" orig-symbols->integers)])))
|
|
(make-ctype basetype
|
|
(lambda (symbols)
|
|
(if (null? symbols) ; probably common
|
|
0
|
|
(let loop ([xs (if (pair? symbols) symbols (list symbols))] [n 0])
|
|
(cond [(null? xs) n]
|
|
[(assq (car xs) symbols->integers) =>
|
|
(lambda (x) (loop (cdr xs) (bitwise-ior (cadr x) n)))]
|
|
[else (raise-type-error s->c (format "~a" (or name "bitmask"))
|
|
symbols)]))))
|
|
(lambda (n)
|
|
(if (zero? n) ; probably common
|
|
'()
|
|
(let loop ([s->i symbols->integers] [l '()])
|
|
(if (null? s->i)
|
|
(reverse l)
|
|
(loop (cdr s->i)
|
|
(let ([i (cadar s->i)])
|
|
(if (and (not (= i 0)) (= i (bitwise-and i n)))
|
|
(cons (caar s->i) l)
|
|
l)))))))))
|
|
|
|
;; Macro wrapper -- no need for a name
|
|
(provide (rename-out [_bitmask* _bitmask]))
|
|
(define-syntax (_bitmask* stx)
|
|
(syntax-case stx ()
|
|
[(_ x ...)
|
|
(with-syntax ([name (syntax-local-name)]) #'(_bitmask 'name x ...))]
|
|
[id (identifier? #'id) #'_bitmask]))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Custom function type macros
|
|
|
|
;; These macros get expanded by the _fun type. They can expand to a form that
|
|
;; looks like (keyword: value ...), where the keyword is one of:
|
|
;; * `type:' for the type that will be used,
|
|
;; * `expr:' an expression that will always be used for these arguments, as
|
|
;; if `= expr' is always given, when an expression is actually
|
|
;; given in an argument specification, it supersedes this.
|
|
;; * `bind:' for an additional binding that holds the initial value,
|
|
;; * `1st-arg:' is used to name an identifier that will be bound to the value
|
|
;; of the 1st foreign argument in pre/post chunks (good for
|
|
;; common cases where the first argument has a special meaning,
|
|
;; eg, for method calls),
|
|
;; * `prev-arg:' similar to 1st-arg: but for the previous argument,
|
|
;; * `pre:' for a binding that will be inserted before the ffi call,
|
|
;; * `post:' for a binding after the ffi call,
|
|
;; * `keywords:' specifying keywords to be used in the surrounding _fun
|
|
;; (the keywords and values follow).
|
|
;; The pre: and post: bindings can be of the form (id => expr) to use the
|
|
;; existing value. Note that if the pre: expression is not (id => expr), then
|
|
;; it means that there is no input for this argument. Also note that if a
|
|
;; custom type is used as an output type of a function, then only the post:
|
|
;; code is used -- for example, this is useful for foreign functions that
|
|
;; allocate a memory block and return it to the user. The resulting wrapper
|
|
;; looks like:
|
|
;; (let* (...bindings for arguments...
|
|
;; ...bindings for bind: identifiers...
|
|
;; ...bindings for pre-code...
|
|
;; (ret-name ffi-call)
|
|
;; ...bindings for post-code...)
|
|
;; return-expression)
|
|
;;
|
|
;; Finally, the code in a custom-function macro needs special treatment when it
|
|
;; comes to dealing with code certificates, so instead of using
|
|
;; `define-syntax', you should use `define-fun-syntax' (used in the same way).
|
|
|
|
;; _?
|
|
;; This is not a normal ffi type -- it is a marker for expressions that should
|
|
;; not be sent to the ffi function. Use this to bind local values in a
|
|
;; computation that is part of an ffi wrapper interface.
|
|
(provide _?)
|
|
(define-fun-syntax _?
|
|
(syntax-id-rules () [(_ . xs) ((type: #f) . xs)] [_ (type: #f)]))
|
|
|
|
;; (_ptr <mode> <type>)
|
|
;; This is for pointers, where mode indicates input or output pointers (or
|
|
;; both). If the mode is `o' (output), then the wrapper will not get an
|
|
;; argument for it, instead it generates the matching argument.
|
|
(provide _ptr)
|
|
(define-fun-syntax _ptr
|
|
(syntax-rules (i o io)
|
|
[(_ i t) (type: _pointer
|
|
pre: (x => (let ([p (malloc t)]) (ptr-set! p t x) p)))]
|
|
[(_ o t) (type: _pointer
|
|
pre: (malloc t)
|
|
post: (x => (ptr-ref x t)))]
|
|
[(_ io t) (type: _pointer
|
|
pre: (x => (let ([p (malloc t)]) (ptr-set! p t x) p))
|
|
post: (x => (ptr-ref x t)))]))
|
|
|
|
;; (_box <type>)
|
|
;; This is similar to a (_ptr io <type>) argument, where the input is expected
|
|
;; to be a box, which is unboxed on entry and modified on exit.
|
|
(provide _box)
|
|
(define-fun-syntax _box
|
|
(syntax-rules ()
|
|
[(_ t) (type: _pointer
|
|
bind: tmp ; need to save the box so we can get back to it
|
|
pre: (x => (let ([p (malloc t)]) (ptr-set! p t (unbox x)) p))
|
|
post: (x => (begin (set-box! tmp (ptr-ref x t)) tmp)))]))
|
|
|
|
;; (_list <mode> <type> [<len>])
|
|
;; Similar to _ptr, except that it is used for converting lists to/from C
|
|
;; vectors. The length is needed for output values where it is used in the
|
|
;; post code, and in the pre code of an output mode to allocate the block. In
|
|
;; any case it can refer to a previous binding for the length of the list which
|
|
;; the C function will most likely require.
|
|
(provide _list)
|
|
(define-fun-syntax _list
|
|
(syntax-rules (i o io)
|
|
[(_ i t ) (type: _pointer
|
|
pre: (x => (list->cblock x t)))]
|
|
[(_ o t n) (type: _pointer
|
|
pre: (malloc n t)
|
|
post: (x => (cblock->list x t n)))]
|
|
[(_ io t n) (type: _pointer
|
|
pre: (x => (list->cblock x t))
|
|
post: (x => (cblock->list x t n)))]))
|
|
|
|
;; (_vector <mode> <type> [<len>])
|
|
;; Same as _list, except that it uses Scheme vectors.
|
|
(provide _vector)
|
|
(define-fun-syntax _vector
|
|
(syntax-rules (i o io)
|
|
[(_ i t ) (type: _pointer
|
|
pre: (x => (vector->cblock x t)))]
|
|
[(_ o t n) (type: _pointer
|
|
pre: (malloc n t)
|
|
post: (x => (cblock->vector x t n)))]
|
|
[(_ io t n) (type: _pointer
|
|
pre: (x => (vector->cblock x t))
|
|
post: (x => (cblock->vector x t n)))]))
|
|
|
|
;; _bytes or (_bytes o n) is for a memory block represented as a Scheme byte
|
|
;; string. _bytes is just like a byte-string, and (_bytes o n) is for
|
|
;; pre-malloc of the string. There is no need for other modes: i or io would
|
|
;; be just like _bytes since the string carries its size information (so there
|
|
;; is no real need for the `o', but it's there for consistency with the above
|
|
;; macros).
|
|
(provide (rename-out [_bytes* _bytes]))
|
|
(define-fun-syntax _bytes*
|
|
(syntax-id-rules (o)
|
|
[(_ o n) (type: _pointer
|
|
pre: (make-sized-byte-string (malloc n) n)
|
|
;; post is needed when this is used as a function output type
|
|
post: (x => (make-sized-byte-string x n)))]
|
|
[(_ . xs) (_bytes . xs)]
|
|
[_ _bytes]))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Tagged pointers
|
|
|
|
;; Make these operations available for unsafe interfaces (they can be used to
|
|
;; grab a hidden tag value and break code).
|
|
(provide cpointer-tag set-cpointer-tag!
|
|
cpointer-has-tag? cpointer-push-tag!)
|
|
|
|
;; Defined as syntax for efficiency, but can be used as procedures too.
|
|
(define-syntax (cpointer-has-tag? stx)
|
|
(syntax-case stx ()
|
|
[(_ cptr tag)
|
|
#'(let ([ptag (cpointer-tag cptr)])
|
|
(if (pair? ptag) (memq tag ptag) (eq? tag ptag)))]
|
|
[id (identifier? #'id)
|
|
#'(lambda (cptr tag) (cpointer-has-tag? cptr tag))]))
|
|
(define-syntax (cpointer-push-tag! stx)
|
|
(syntax-case stx ()
|
|
[(_ cptr tag)
|
|
#'(let ([ptag (cpointer-tag cptr)])
|
|
(set-cpointer-tag! cptr
|
|
(cond [(not ptag) tag]
|
|
[(pair? ptag) (cons tag ptag)]
|
|
[else (list tag ptag)])))]
|
|
[id (identifier? #'id)
|
|
#'(lambda (cptr tag) (cpointer-push-tag! cptr tag))]))
|
|
|
|
(define (cpointer-maker nullable?)
|
|
(case-lambda
|
|
[(tag) ((cpointer-maker nullable?) tag #f #f #f)]
|
|
[(tag ptr-type) ((cpointer-maker nullable?) tag ptr-type #f #f)]
|
|
[(tag ptr-type scheme->c c->scheme)
|
|
(let* ([tag->C (string->symbol (format "~a->C" tag))]
|
|
[error-str (format "~a`~a' pointer"
|
|
(if nullable? "" "non-null ") tag)]
|
|
[error* (lambda (p) (raise-type-error tag->C error-str p))])
|
|
(define-syntax-rule (tag-or-error ptr t)
|
|
(let ([p ptr])
|
|
(if (cpointer? p)
|
|
(if (cpointer-has-tag? p t) p (error* p))
|
|
(error* p))))
|
|
(define-syntax-rule (tag-or-error/null ptr t)
|
|
(let ([p ptr])
|
|
(if (cpointer? p)
|
|
(and p (if (cpointer-has-tag? p t) p (error* p)))
|
|
(error* p))))
|
|
(make-ctype (or ptr-type _pointer)
|
|
;; bad hack: `if's outside the lambda for efficiency
|
|
(if nullable?
|
|
(if scheme->c
|
|
(lambda (p) (tag-or-error/null (scheme->c p) tag))
|
|
(lambda (p) (tag-or-error/null p tag)))
|
|
(if scheme->c
|
|
(lambda (p) (tag-or-error (scheme->c p) tag))
|
|
(lambda (p) (tag-or-error p tag))))
|
|
(if nullable?
|
|
(if c->scheme
|
|
(lambda (p) (when p (cpointer-push-tag! p tag)) (c->scheme p))
|
|
(lambda (p) (when p (cpointer-push-tag! p tag)) p))
|
|
(if c->scheme
|
|
(lambda (p)
|
|
(if p (cpointer-push-tag! p tag) (error* p))
|
|
(c->scheme p))
|
|
(lambda (p)
|
|
(if p (cpointer-push-tag! p tag) (error* p))
|
|
p)))))]))
|
|
|
|
;; This is a kind of a pointer that gets a specific tag when converted to
|
|
;; Scheme, and accepts only such tagged pointers when going to C. An optional
|
|
;; `ptr-type' can be given to be used as the base pointer type, instead of
|
|
;; _pointer, `scheme->c' and `c->scheme' can be used for adding conversion
|
|
;; hooks.
|
|
(define* _cpointer (cpointer-maker #f))
|
|
|
|
;; Similar to the above, but can tolerate null pointers (#f).
|
|
(define* _cpointer/null (cpointer-maker #t))
|
|
|
|
(define (cast p from-type to-type)
|
|
(unless (ctype? from-type)
|
|
(raise-type-error 'cast "ctype" from-type))
|
|
(unless (ctype? to-type)
|
|
(raise-type-error 'cast "ctype" to-type))
|
|
(unless (= (ctype-sizeof to-type)
|
|
(ctype-sizeof from-type))
|
|
(raise-mismatch-error 'cast
|
|
(format "representation sizes of from and to types differ: ~e and "
|
|
(ctype-sizeof from-type))
|
|
(ctype-sizeof to-type)))
|
|
(let ([p2 (malloc from-type)])
|
|
(ptr-set! p2 from-type p)
|
|
(ptr-ref p2 to-type)))
|
|
|
|
(define* (_or-null ctype)
|
|
(let ([coretype (ctype-coretype ctype)])
|
|
(unless (memq coretype '(pointer gcpointer fpointer))
|
|
(raise-type-error '_or-null "ctype buit on pointer, gcpointer, or fpointer" ctype))
|
|
(make-ctype
|
|
(case coretype
|
|
[(pointer) _pointer]
|
|
[(gcpointer) _gcpointer]
|
|
[(fpointer) _fpointer])
|
|
(lambda (v) (and v (cast v _pointer _pointer)))
|
|
(lambda (v) (and v (cast v _pointer ctype))))))
|
|
|
|
(define* (_gcable ctype)
|
|
(unless (memq (ctype-coretype ctype) '(pointer gcpointer))
|
|
(raise-type-error '_or-null "pointer ctype" ctype))
|
|
(let loop ([ctype ctype])
|
|
(if (eq? ctype 'pointer)
|
|
_gcpointer
|
|
(make-ctype
|
|
(loop (ctype-basetype ctype))
|
|
(ctype-scheme->c ctype)
|
|
(ctype-c->scheme ctype)))))
|
|
|
|
(define (ctype-coretype c)
|
|
(let loop ([c (ctype-basetype c)])
|
|
(if (symbol? c)
|
|
c
|
|
(loop (ctype-basetype c)))))
|
|
|
|
;; A macro version of the above two functions, using the defined name for a tag
|
|
;; string, and defining a predicate too. The name should look like `_foo', the
|
|
;; predicate will be `foo?', and the tag will be "foo". In addition, `foo-tag'
|
|
;; is bound to the tag. The optional `ptr-type', `scheme->c', and `c->scheme'
|
|
;; arguments are the same as those of `_cpointer'. `_foo' will be bound to the
|
|
;; _cpointer type, and `_foo/null' to the _cpointer/null type.
|
|
(provide define-cpointer-type)
|
|
(define-syntax (define-cpointer-type stx)
|
|
(syntax-case stx ()
|
|
[(_ _TYPE) #'(define-cpointer-type _TYPE #f #f #f)]
|
|
[(_ _TYPE ptr-type) #'(define-cpointer-type _TYPE ptr-type #f #f)]
|
|
[(_ _TYPE ptr-type scheme->c c->scheme)
|
|
(and (identifier? #'_TYPE)
|
|
(regexp-match #rx"^_.+" (symbol->string (syntax-e #'_TYPE))))
|
|
(let ([name (cadr (regexp-match #rx"^_(.+)$"
|
|
(symbol->string (syntax-e #'_TYPE))))])
|
|
(define (id . strings)
|
|
(datum->syntax
|
|
#'_TYPE (string->symbol (apply string-append strings)) #'_TYPE))
|
|
(with-syntax ([name-string name]
|
|
[TYPE? (id name "?")]
|
|
[TYPE-tag (id name "-tag")]
|
|
[_TYPE/null (id "_" name "/null")])
|
|
#'(define-values (_TYPE _TYPE/null TYPE? TYPE-tag)
|
|
(let ([TYPE-tag name-string])
|
|
(values (_cpointer TYPE-tag ptr-type scheme->c c->scheme)
|
|
(_cpointer/null TYPE-tag ptr-type scheme->c c->scheme)
|
|
(lambda (x)
|
|
(and (cpointer? x) (cpointer-has-tag? x TYPE-tag)))
|
|
TYPE-tag)))))]))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Struct wrappers
|
|
|
|
(define (compute-offsets types alignment)
|
|
(let ([alignment (if (memq alignment '(#f 1 2 4 8 16))
|
|
alignment
|
|
#f)])
|
|
(let loop ([ts types] [cur 0] [r '()])
|
|
(if (null? ts)
|
|
(reverse r)
|
|
(let* ([algn (if alignment
|
|
(min alignment (ctype-alignof (car ts)))
|
|
(ctype-alignof (car ts)))]
|
|
[pos (+ cur (modulo (- (modulo cur algn)) algn))])
|
|
(loop (cdr ts)
|
|
(+ pos (ctype-sizeof (car ts)))
|
|
(cons pos r)))))))
|
|
|
|
;; Simple structs: call this with a list of types, and get a type that marshals
|
|
;; C structs to/from Scheme lists.
|
|
(define* (_list-struct #:alignment [alignment #f] . types)
|
|
(let ([stype (make-cstruct-type types #f alignment)]
|
|
[offsets (compute-offsets types alignment)]
|
|
[len (length types)])
|
|
(make-ctype stype
|
|
(lambda (vals)
|
|
(unless (and (list vals) (= len (length vals)))
|
|
(raise-type-error 'list-struct (format "list of ~a items" len) vals))
|
|
(let ([block (malloc stype)])
|
|
(for-each (lambda (type ofs val) (ptr-set! block type 'abs ofs val))
|
|
types offsets vals)
|
|
block))
|
|
(lambda (block)
|
|
(map (lambda (type ofs) (ptr-ref block type 'abs ofs))
|
|
types offsets)))))
|
|
|
|
;; (define-cstruct _foo ([slot type] ...))
|
|
;; or
|
|
;; (define-cstruct (_foo _super) ([slot type] ...))
|
|
;; defines a type called _foo for a C struct, with user-procedues: make-foo,
|
|
;; foo? foo-slot... and set-foo-slot!.... The `_' prefix is required. Objects
|
|
;; of this new type are actually cpointers, with a type tag that is "foo" and
|
|
;; (possibly more if the first type is itself a cstruct type or if a super type
|
|
;; is given,) provided as foo-tag, and tags of pointers are checked before
|
|
;; attempting to use them (see define-cpointer-type above). Note that since
|
|
;; structs are implemented as pointers, they can be used for a _pointer input
|
|
;; to a foreign function: their address will be used, to make this possible,
|
|
;; the corresponding cpointer type is defined as _foo-pointer. If a super
|
|
;; cstruct type is given, the constructor function expects values for every
|
|
;; field of the super type as well as other fields that are specified, and a
|
|
;; slot named `super' can be used to extract this initial struct -- although
|
|
;; pointers to the new struct type can be used as pointers to the super struct
|
|
;; type.
|
|
(provide define-cstruct)
|
|
(define-syntax (define-cstruct stx)
|
|
(define (make-syntax _TYPE-stx has-super? slot-names-stx slot-types-stx alignment-stx)
|
|
(define name
|
|
(cadr (regexp-match #rx"^_(.+)$" (symbol->string (syntax-e _TYPE-stx)))))
|
|
(define slot-names (map (lambda (x) (symbol->string (syntax-e x)))
|
|
(syntax->list slot-names-stx)))
|
|
(define 1st-type
|
|
(let ([xs (syntax->list slot-types-stx)]) (and (pair? xs) (car xs))))
|
|
(define (id . strings)
|
|
(datum->syntax
|
|
_TYPE-stx (string->symbol (apply string-append strings)) _TYPE-stx))
|
|
(define (ids name-func)
|
|
(map (lambda (s)
|
|
(datum->syntax
|
|
_TYPE-stx
|
|
(string->symbol (apply string-append (name-func s)))
|
|
_TYPE-stx))
|
|
slot-names))
|
|
(define (safe-id=? x y)
|
|
(and (identifier? x) (identifier? y) (free-identifier=? x y)))
|
|
(with-syntax
|
|
([has-super? has-super?]
|
|
[name-string name]
|
|
[struct-string (format "struct:~a" name)]
|
|
[(slot ...) slot-names-stx]
|
|
[(slot-type ...) slot-types-stx]
|
|
[TYPE (id name)]
|
|
[_TYPE _TYPE-stx]
|
|
[_TYPE-pointer (id "_"name"-pointer")]
|
|
[_TYPE-pointer/null (id "_"name"-pointer/null")]
|
|
[_TYPE/null (id "_"name"/null")]
|
|
[_TYPE* (id "_"name"*")]
|
|
[TYPE? (id name"?")]
|
|
[make-TYPE (id "make-"name)]
|
|
[list->TYPE (id "list->"name)]
|
|
[list*->TYPE (id "list*->"name)]
|
|
[TYPE->list (id name"->list")]
|
|
[TYPE->list* (id name"->list*")]
|
|
[TYPE-tag (id name"-tag")]
|
|
[(stype ...) (ids (lambda (s) `(,name"-",s"-type")))]
|
|
[(TYPE-SLOT ...) (ids (lambda (s) `(,name"-",s)))]
|
|
[(set-TYPE-SLOT! ...) (ids (lambda (s) `("set-",name"-",s"!")))]
|
|
[(offset ...) (generate-temporaries
|
|
(ids (lambda (s) `(,s"-offset"))))]
|
|
[alignment alignment-stx])
|
|
(with-syntax ([get-super-info
|
|
;; the 1st-type might be a pointer to this type
|
|
(if (or (safe-id=? 1st-type #'_TYPE-pointer/null)
|
|
(safe-id=? 1st-type #'_TYPE-pointer))
|
|
#'(values #f '() #f #f #f #f)
|
|
#`(cstruct-info #,1st-type
|
|
(lambda () (values #f '() #f #f #f #f))))])
|
|
#'(begin
|
|
(define-syntax TYPE
|
|
(make-struct-info
|
|
(lambda ()
|
|
(list #f ; no struct:
|
|
(quote-syntax make-TYPE)
|
|
(quote-syntax TYPE?)
|
|
(reverse (list (quote-syntax TYPE-SLOT) ...))
|
|
(reverse (list (quote-syntax set-TYPE-SLOT!) ...))
|
|
#t))))
|
|
(define-values (_TYPE _TYPE-pointer _TYPE-pointer/null TYPE? TYPE-tag
|
|
make-TYPE TYPE-SLOT ... set-TYPE-SLOT! ...
|
|
list->TYPE list*->TYPE TYPE->list TYPE->list*)
|
|
(let-values ([(super-pointer super-tags super-types super-offsets
|
|
super->list* list*->super)
|
|
get-super-info])
|
|
(define-cpointer-type _TYPE super-pointer)
|
|
;; these makes it possible to use recursive pointer definitions
|
|
(define _TYPE-pointer _TYPE)
|
|
(define _TYPE-pointer/null _TYPE/null)
|
|
(let*-values ([(stype ...) (values slot-type ...)]
|
|
[(types) (list stype ...)]
|
|
[(alignment-v) alignment]
|
|
[(offsets) (compute-offsets types alignment-v)]
|
|
[(offset ...) (apply values offsets)])
|
|
(define all-tags (cons TYPE-tag super-tags))
|
|
(define _TYPE*
|
|
;; c->scheme adjusts all tags
|
|
(let* ([cst (make-cstruct-type types #f alignment-v)]
|
|
[t (_cpointer TYPE-tag cst)]
|
|
[c->s (ctype-c->scheme t)])
|
|
(make-ctype cst (ctype-scheme->c t)
|
|
;; hack: modify & reuse the procedure made by _cpointer
|
|
(lambda (p)
|
|
(if p (set-cpointer-tag! p all-tags) (c->s p))
|
|
p))))
|
|
(define-values (all-types all-offsets)
|
|
(if (and has-super? super-types super-offsets)
|
|
(values (append super-types (cdr types))
|
|
(append super-offsets (cdr offsets)))
|
|
(values types offsets)))
|
|
(define (TYPE-SLOT x)
|
|
(unless (TYPE? x)
|
|
(raise-type-error 'TYPE-SLOT struct-string x))
|
|
(ptr-ref x stype 'abs offset))
|
|
...
|
|
(define (set-TYPE-SLOT! x slot)
|
|
(unless (TYPE? x)
|
|
(raise-type-error 'set-TYPE-SLOT! struct-string 0 x slot))
|
|
(ptr-set! x stype 'abs offset slot))
|
|
...
|
|
(define make-TYPE
|
|
(if (and has-super? super-types super-offsets)
|
|
;; init using all slots
|
|
(lambda vals
|
|
(if (= (length vals) (length all-types))
|
|
(let ([block (malloc _TYPE*)])
|
|
(set-cpointer-tag! block all-tags)
|
|
(for-each (lambda (type ofs value)
|
|
(ptr-set! block type 'abs ofs value))
|
|
all-types all-offsets vals)
|
|
block)
|
|
(error '_TYPE "expecting ~s values, got ~s: ~e"
|
|
(length all-types) (length vals) vals)))
|
|
;; normal initializer
|
|
(lambda (slot ...)
|
|
(let ([block (malloc _TYPE*)])
|
|
(set-cpointer-tag! block all-tags)
|
|
(ptr-set! block stype 'abs offset slot)
|
|
...
|
|
block))))
|
|
(define (list->TYPE vals) (apply make-TYPE vals))
|
|
(define (list*->TYPE vals)
|
|
(cond
|
|
[(TYPE? vals) vals]
|
|
[(= (length vals) (length all-types))
|
|
(let ([block (malloc _TYPE*)])
|
|
(set-cpointer-tag! block all-tags)
|
|
(for-each
|
|
(lambda (type ofs value)
|
|
(let-values
|
|
([(ptr tags types offsets T->list* list*->T)
|
|
(cstruct-info
|
|
type
|
|
(lambda () (values #f '() #f #f #f #f)))])
|
|
(ptr-set! block type 'abs ofs
|
|
(if list*->T (list*->T value) value))))
|
|
all-types all-offsets vals)
|
|
block)]
|
|
[else (error '_TYPE "expecting ~s values, got ~s: ~e"
|
|
(length all-types) (length vals) vals)]))
|
|
(define (TYPE->list x)
|
|
(unless (TYPE? x)
|
|
(raise-type-error 'TYPE-list struct-string x))
|
|
(map (lambda (type ofs) (ptr-ref x type 'abs ofs))
|
|
all-types all-offsets))
|
|
(define (TYPE->list* x)
|
|
(unless (TYPE? x)
|
|
(raise-type-error 'TYPE-list struct-string x))
|
|
(map (lambda (type ofs)
|
|
(let-values
|
|
([(v) (ptr-ref x type 'abs ofs)]
|
|
[(ptr tags types offsets T->list* list*->T)
|
|
(cstruct-info
|
|
type
|
|
(lambda () (values #f '() #f #f #f #f)))])
|
|
(if T->list* (T->list* v) v)))
|
|
all-types all-offsets))
|
|
(cstruct-info
|
|
_TYPE* 'set!
|
|
_TYPE all-tags all-types all-offsets TYPE->list* list*->TYPE)
|
|
(values _TYPE* _TYPE-pointer _TYPE-pointer/null TYPE? TYPE-tag
|
|
make-TYPE TYPE-SLOT ... set-TYPE-SLOT! ...
|
|
list->TYPE list*->TYPE TYPE->list TYPE->list*))))))))
|
|
(define (err what . xs)
|
|
(apply raise-syntax-error #f
|
|
(if (list? what) (apply string-append what) what)
|
|
stx xs))
|
|
(syntax-case stx ()
|
|
[(_ type ([slot slot-type] ...) . more)
|
|
(let-values ([(_TYPE _SUPER)
|
|
(syntax-case #'type ()
|
|
[(t s) (values #'t #'s)]
|
|
[_ (values #'type #f)])]
|
|
[(alignment)
|
|
(syntax-case #'more ()
|
|
[() #'#f]
|
|
[(#:alignment) (err "missing expression for #:alignment")]
|
|
[(#:alignment a) #'a]
|
|
[(#:alignment a x . _) (err "unexpected form" #'x)]
|
|
[(x . _) (err (if (keyword? (syntax-e #'x))
|
|
"unknown keyword" "unexpected form")
|
|
#'x)])])
|
|
(unless (identifier? _TYPE)
|
|
(err "bad type, expecting a _name identifier or (_name super-ctype)"
|
|
_TYPE))
|
|
(unless (regexp-match? #rx"^_." (symbol->string (syntax-e _TYPE)))
|
|
(err "cstruct name must begin with a `_'" _TYPE))
|
|
(for ([s (in-list (syntax->list #'(slot ...)))])
|
|
(unless (identifier? s)
|
|
(err "bad field name, expecting an identifier identifier" s)))
|
|
(if _SUPER
|
|
(make-syntax _TYPE #t
|
|
#`(#,(datum->syntax _TYPE 'super _TYPE) slot ...)
|
|
#`(#,_SUPER slot-type ...)
|
|
alignment)
|
|
(make-syntax _TYPE #f #'(slot ...) #`(slot-type ...) alignment)))]
|
|
;; specific errors for bad slot specs, leave the rest for a generic error
|
|
[(_ type (bad ...) . more)
|
|
(err "bad slot specification, expecting [name ctype]"
|
|
(ormap (lambda (s) (syntax-case s () [[n ct] #t] [_ s]))
|
|
(syntax->list #'(bad ...))))]
|
|
[(_ type bad . more)
|
|
(err "bad slot specification, expecting a sequence of [name ctype]"
|
|
#'bad)]))
|
|
|
|
;; helper for the above: keep runtime information on structs
|
|
(define cstruct-info
|
|
(let ([table (make-weak-hasheq)])
|
|
(lambda (cstruct msg/fail-thunk . args)
|
|
(cond [(eq? 'set! msg/fail-thunk)
|
|
(hash-set! table cstruct (make-ephemeron cstruct args))]
|
|
[(and cstruct ; might get a #f if there were no slots
|
|
(hash-ref table cstruct (lambda () #f)))
|
|
=> (lambda (xs)
|
|
(let ([v (ephemeron-value xs)])
|
|
(if v (apply values v) (msg/fail-thunk))))]
|
|
[else (msg/fail-thunk)]))))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;;
|
|
|
|
(define prim-synonyms
|
|
#hasheq((double* . double)
|
|
(fixint . long)
|
|
(ufixint . ulong)
|
|
(fixnum . long)
|
|
(ufixnum . ulong)
|
|
(path . bytes)
|
|
(symbol . bytes)
|
|
(scheme . pointer)))
|
|
|
|
(define (ctype->layout c)
|
|
(let ([b (ctype-basetype c)])
|
|
(cond
|
|
[(ctype? b) (ctype->layout b)]
|
|
[(list? b) (map ctype->layout b)]
|
|
[else (hash-ref prim-synonyms b b)])))
|
|
|
|
;; ----------------------------------------------------------------------------
|
|
;; Misc utilities
|
|
|
|
;; Used by set-ffi-obj! to get the actual value so it can be kept around
|
|
(define (get-lowlevel-object x type)
|
|
(let ([basetype (ctype-basetype type)])
|
|
(if (ctype? basetype)
|
|
(let ([s->c (ctype-scheme->c type)])
|
|
(get-lowlevel-object (if s->c (s->c x) x) basetype))
|
|
(values x type))))
|
|
|
|
;; Converting Scheme lists to/from C vectors (going back requires a length)
|
|
(define* (list->cblock l type)
|
|
(if (null? l)
|
|
#f ; null => NULL
|
|
(let ([cblock (malloc (length l) type)])
|
|
(let loop ([l l] [i 0])
|
|
(unless (null? l)
|
|
(ptr-set! cblock type i (car l))
|
|
(loop (cdr l) (add1 i))))
|
|
cblock)))
|
|
(provide (protect-out cblock->list))
|
|
(define (cblock->list cblock type len)
|
|
(cond [(zero? len) '()]
|
|
[(cpointer? cblock)
|
|
(let loop ([i (sub1 len)] [r '()])
|
|
(if (< i 0)
|
|
r
|
|
(loop (sub1 i) (cons (ptr-ref cblock type i) r))))]
|
|
[else (error 'cblock->list
|
|
"expecting a non-void pointer, got ~s" cblock)]))
|
|
|
|
;; Converting Scheme vectors to/from C vectors
|
|
(define* (vector->cblock v type)
|
|
(let ([len (vector-length v)])
|
|
(if (zero? len)
|
|
#f ; #() => NULL
|
|
(let ([cblock (malloc len type)])
|
|
(let loop ([i 0])
|
|
(when (< i len)
|
|
(ptr-set! cblock type i (vector-ref v i))
|
|
(loop (add1 i))))
|
|
cblock))))
|
|
(provide (protect-out cblock->vector))
|
|
(define (cblock->vector cblock type len)
|
|
(cond [(zero? len) '#()]
|
|
[(cpointer? cblock)
|
|
(let ([v (make-vector len)])
|
|
(let loop ([i (sub1 len)])
|
|
(unless (< i 0)
|
|
(vector-set! v i (ptr-ref cblock type i))
|
|
(loop (sub1 i))))
|
|
v)]
|
|
[else (error 'cblock->vector
|
|
"expecting a non-void pointer, got ~s" cblock)]))
|
|
|
|
;; Useful for automatic definitions
|
|
;; If a provided regexp begins with a "^" or ends with a "$", then
|
|
;; `regexp-replace' is used, otherwise use `regexp-replace*'.
|
|
(define* (regexp-replaces x rs)
|
|
(let loop ([str (if (bytes? x) (bytes->string/utf-8 x) (format "~a" x))]
|
|
[rs rs])
|
|
(if (null? rs)
|
|
str
|
|
(loop ((if (regexp-match #rx"^\\^|\\$$"
|
|
(if (regexp? (caar rs))
|
|
(object-name (caar rs)) (caar rs)))
|
|
regexp-replace regexp-replace*)
|
|
(caar rs) str (cadar rs)) (cdr rs)))))
|
|
|
|
;; A facility for running finalizers using executors. The "stubborn" kind
|
|
;; of will executor is provided by '#%foreign, and it doesn't get GC'ed if
|
|
;; any finalizers are attached to it (while the normal kind can get GCed
|
|
;; even if a thread that is otherwise inaccessible is blocked on the executor).
|
|
;; Also it registers level-2 finalizers (which are run after non-late weak
|
|
;; boxes are cleared).
|
|
(define killer-executor (make-stubborn-will-executor))
|
|
(define killer-thread #f)
|
|
|
|
(define* (register-finalizer obj finalizer)
|
|
(unless killer-thread
|
|
(let ([priviledged-custodian ((get-ffi-obj 'scheme_make_custodian #f (_fun _pointer -> _scheme)) #f)])
|
|
(set! killer-thread
|
|
(parameterize ([current-custodian priviledged-custodian])
|
|
(thread (lambda ()
|
|
(let loop () (will-execute killer-executor) (loop))))))))
|
|
(will-register killer-executor obj finalizer))
|