Newer
Older
;;;; -*- Mode: lisp; indent-tabs-mode: nil -*-
;;;
;;; cffi-ecl.lisp --- ECL backend for CFFI.
;;;
;;; Copyright (C) 2005-2006, James Bielman <jamesjb@jamesjb.com>
;;;
;;; Permission is hereby granted, free of charge, to any person
;;; obtaining a copy of this software and associated documentation
;;; files (the "Software"), to deal in the Software without
;;; restriction, including without limitation the rights to use, copy,
;;; modify, merge, publish, distribute, sublicense, and/or sell copies
;;; of the Software, and to permit persons to whom the Software is
;;; furnished to do so, subject to the following conditions:
;;;
;;; The above copyright notice and this permission notice shall be
;;; included in all copies or substantial portions of the Software.
;;;
;;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
;;; EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
;;; MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
;;; NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
;;; HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
;;; WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
;;; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
;;; DEALINGS IN THE SOFTWARE.
;;;
;;;# Administrivia
(defpackage #:cffi-sys
(:import-from #:si #:null-pointer-p)
#:with-foreign-pointer
#:null-pointer
#:null-pointer-p
#:inc-pointer
#:make-pointer
#:pointer-address
#:%mem-set
#:%foreign-type-alignment
#:%foreign-type-size
#:%load-foreign-library
#:%foreign-symbol-pointer))
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
;;;
;;; ECL allows many ways of calling a foreign function, and also many
;;; ways of finding the pointer associated to a function name. They
;;; depend on whether the FFI relies on libffi or on the C/C++ compiler,
;;; and whether they use the shared library loader to locate symbols
;;; or they are linked by the linker.
;;;
;;; :DFFI
;;;
;;; ECL uses libffi to call foreign functions. The only way to find out
;;; foreign symbols is by loading shared libraries and using dlopen()
;;; or similar.
;;;
;;; :DLOPEN
;;;
;;; ECL compiles FFI code as C/C++ statements. The names are resolved
;;; at run time by the shared library loader every time the function
;;; is called
;;;
;;; :C/C++
;;;
;;; ECL compiles FFI code as C/C++ statements, but the name resolution
;;; happens at link time. In this case you have to tell the ECL
;;; compiler which are the right ld-flags (c:*ld-flags*) to link in
;;; the library.
;;;
(defvar *cffi-ecl-method*
#+dffi :dffi
#+(and dlopen (not dffi)) :dlopen
#-(or dffi dlopen) :c/c++
"The type of code that CFFI generates for ECL: :DFFI when using the
dynamical foreign function interface; :DLOPEN when using C code and
dynamical references to symbols; :C/C++ for C/C++ code with static
references to symbols.")
(defun canonicalize-symbol-name-case (name)
(declare (string name))
(string-upcase name))
"Allocate SIZE bytes of foreign-addressable memory."
(si:allocate-foreign-data :void size))
(defun foreign-free (ptr)
"Free a pointer PTR allocated by FOREIGN-ALLOC."
(si:free-foreign-data ptr))
(defmacro with-foreign-pointer ((var size &optional size-var) &body body)
"Bind VAR to SIZE bytes of foreign memory during BODY. The
pointer in VAR is invalid beyond the dynamic extent of BODY, and
may be stack-allocated if supported by the implementation. If
SIZE-VAR is supplied, it will be bound to SIZE during BODY."
(unless size-var
(setf size-var (gensym "SIZE")))
`(let* ((,size-var ,size)
(unwind-protect
(progn ,@body)
(foreign-free ,var))))
;;;# Misc. Pointer Operations
(deftype foreign-pointer ()
'si:foreign-data)
(si:allocate-foreign-data :void 0))
(ffi:make-pointer (+ (ffi:pointer-address ptr) offset) :void))
(defun pointerp (ptr)
"Return true if PTR is a foreign pointer."
(typep ptr 'si:foreign-data))
(defun pointer-eq (ptr1 ptr2)
"Return true if PTR1 and PTR2 point to the same address."
(= (ffi:pointer-address ptr1) (ffi:pointer-address ptr2)))
(defun make-pointer (address)
"Return a pointer pointing to ADDRESS."
(ffi:make-pointer address :void))
(defun pointer-address (ptr)
"Return the address pointed to by PTR."
(ffi:pointer-address ptr))
;;;# Shareable Vectors
;;;
;;; This interface is very experimental. WITH-POINTER-TO-VECTOR-DATA
;;; should be defined to perform a copy-in/copy-out if the Lisp
;;; implementation can't do this.
(defun make-shareable-byte-vector (size)
"Create a Lisp vector of SIZE bytes that can passed to
WITH-POINTER-TO-VECTOR-DATA."
(make-array size :element-type '(unsigned-byte 8)))
(defmacro with-pointer-to-vector-data ((ptr-var vector) &body body)
"Bind PTR-VAR to a foreign pointer to the data in VECTOR."
`(let ((,ptr-var (si:make-foreign-data-from-array ,vector)))
'((:char :byte "char")
(:unsigned-char :unsigned-byte "unsigned char")
(:short :short "short")
(:unsigned-short :unsigned-short "unsigned short")
(:int :int "int")
(:unsigned-int :unsigned-int "unsigned int")
(:long :long "long")
(:unsigned-long :unsigned-long "unsigned long")
#+long-long
(:long-long :long-long "long long")
#+long-long
(:unsigned-long-long :unsigned-long-long "unsigned long long")
(:float :float "float")
(:double :double "double")
(:pointer :pointer-void "void*")
(:void :void "void")))
"Convert a CFFI type keyword to an ECL type keyword."
(or (second (find type-keyword +translation-table+ :key #'first))
(error "~S is not a valid CFFI type" type-keyword)))
(defun ecl-type->c-type (type-keyword)
"Convert a CFFI type keyword to an valid C type keyword."
(or (third (find type-keyword +translation-table+ :key #'second))
(error "~S is not a valid CFFI type" type-keyword)))
(defun %foreign-type-size (type-keyword)
"Return the size in bytes of a foreign type."
(nth-value 0 (ffi:size-of-foreign-type
(defun %foreign-type-alignment (type-keyword)
"Return the alignment in bytes of a foreign type."
(nth-value 1 (ffi:size-of-foreign-type
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
;;;# Dereferencing
(defun %mem-ref (ptr type &optional (offset 0))
"Dereference an object of TYPE at OFFSET bytes from PTR."
(let* ((type (cffi-type->ecl-type type))
(type-size (ffi:size-of-foreign-type type)))
(si:foreign-data-ref-elt
(si:foreign-data-recast ptr (+ offset type-size) :void) offset type)))
(defun %mem-set (value ptr type &optional (offset 0))
"Set an object of TYPE at OFFSET bytes from PTR."
(let* ((type (cffi-type->ecl-type type))
(type-size (ffi:size-of-foreign-type type)))
(si:foreign-data-set-elt
(si:foreign-data-recast ptr (+ offset type-size) :void)
offset type value)))
;;; Inline versions that use C expressions instead of function calls.
(defparameter +mem-ref-strings+
(loop for (cffi-type ecl-type c-string) in +translation-table+
for string = (format nil "*((~A *)(((char*)#0)+#1))" c-string)
collect (list cffi-type ecl-type string)))
(defparameter +mem-set-strings+
(loop for (cffi-type ecl-type c-string) in +translation-table+
for string = (format nil "*((~A *)(((char*)#0)+#1))=#2" c-string)
collect (list cffi-type ecl-type string)))
(define-compiler-macro %mem-ref (&whole whole ptr type &optional (offset 0))
(if (and (constantp type) (constantp offset))
(let ((record (assoc (eval type) +mem-ref-strings+)))
`(ffi:c-inline (,ptr ,offset)
(:pointer-void :cl-index) ; argument types
,(second record) ; return type
,(third record) ; the precomputed expansion
:one-liner t))
whole))
(define-compiler-macro %mem-set (&whole whole value ptr type &optional (offset 0))
(if (and (constantp type) (constantp offset))
(let ((record (assoc (eval type) +mem-set-strings+)))
`(ffi:c-inline (,ptr ,offset ,value) ; arguments with type translated
(:pointer-void :cl-index ,(second record))
:void ; does not return anything
,(third record) ; precomputed expansion
:one-liner t))
whole))
(defconstant +ecl-inline-codes+ "#0,#1,#2,#3,#4,#5,#6,#7,#8,#9,#a,#b,#c,#d,#e,#f,#g,#h,#i,#j,#k,#l,#m,#n,#o,#p,#q,#r,#s,#t,#u,#v,#w,#x,#y,#z")
(defun c-inline-function-pointer-call (pointer types values return-type)
(cond ((not (stringp pointer))
`(ffi:c-inline
,(list* pointer values)
,(list* :pointer-void types) ,return-type
,(with-output-to-string (s)
(let ((types (mapcar #'ecl-type->c-type types)))
;; On AMD64, the following code only works with the extra
;; argument ",...". If this is not present, functions
;; like sprintf do not work
(format s "((~A (*)(~@[~{~A,~}...~]))(#0))(~A)"
(ecl-type->c-type return-type) types
(subseq +ecl-inline-codes+ 3
(max 3 (+ 2 (* (length values) 3)))))))
:one-liner t :side-effects t))
((eq *cffi-ecl-method* :c/c++)
`(ffi:c-inline ,values ,types ,return-type
,(with-output-to-string (s)
(let ((types (mapcar #'ecl-type->c-type types)))
;; On AMD64, the following code only works with the extra
;; argument ",...". If this is not present, functions
;; like sprintf do not work
(format s "{ extern ~A ~A(~@[~{~A~^, ~}~]); ~A~A(~A); }"
(ecl-type->c-type return-type) pointer types
(if (eq return-type :void) "" "@(return) = ")
pointer
(subseq +ecl-inline-codes+ 0
(max 0 (1- (* (length values) 3)))))))
:one-liner nil :side-effects t))
(t
(c-inline-function-pointer-call
`(%foreign-symbol-pointer ,pointer nil)
types values return-type))))
(defun dffi-function-pointer-call (pointer types values return-type)
(when (stringp pointer)
(setf pointer `(%foreign-symbol-pointer ,pointer nil)))
#-dffi
`(error "In interpreted code, attempted to call a foreign function~% ~A~%~
but ECL was built without support for that." ,pointer)
#+dffi
`(si::call-cfun ,pointer ,return-type (list ,@types) (list ,@values)))
#.(cl:when (>= ext:+ecl-version-number+ 100402)
(cl:pushnew :ecl-with-backend cl:*features*)
cl:nil)
(defun produce-function-pointer-call (pointer types values return-type)
(if (eq *cffi-dffi-method* :dffi)
(dffi-function-pointer-call pointer types values return-type)
(c-inline-function-pointer-call pointer types values return-type)))
#+ecl-with-backend
`(ext:with-backend
:bytecodes
,(dffi-function-pointer-call pointer types values return-type)
:c/c++
,(c-inline-function-pointer-call pointer types values return-type)))
(defun foreign-funcall-parse-args (args)
"Return three values, lists of arg types, values, and result type."
(let ((return-type :void))
(loop for (type arg) on args by #'cddr
finally (return (values types values return-type)))))
Stelian Ionescu
committed
(defmacro %foreign-funcall (name args &key library convention)
Stelian Ionescu
committed
(declare (ignore library convention))
(multiple-value-bind (types values return-type)
(foreign-funcall-parse-args args)
(produce-function-pointer-call name types values return-type)))
Stelian Ionescu
committed
(defmacro %foreign-funcall-pointer (ptr args &key convention)
"Funcall a pointer to a foreign function."
Stelian Ionescu
committed
(declare (ignore convention))
(multiple-value-bind (types values return-type)
(foreign-funcall-parse-args args)
(produce-function-pointer-call ptr types values return-type)))
(defun %load-foreign-library (name path)
"Load a foreign library."
(declare (ignore name))
#-dffi (error "LOAD-FOREIGN-LIBRARY requires ECL's DFFI support. Use ~
FFI:LOAD-FOREIGN-LIBRARY with a constant argument instead.")
#+dffi
(handler-case (si:load-foreign-module path)
(file-error ()
(error "file error while trying to load `~A'" path))))
(defun %close-foreign-library (handle)
(error "%CLOSE-FOREIGN-LIBRARY unimplemented."))
(defun native-namestring (pathname)
(namestring pathname))
;;; Create a package to contain the symbols for callback functions.
;;; We want to redefine callbacks with the same symbol so the internal
;;; data structures are reused.
(defpackage #:cffi-callbacks
(:use))
;;; Intern a symbol in the CFFI-CALLBACKS package used to name the
;;; internal callback for NAME.
(eval-when (:compile-toplevel :load-toplevel :execute)
(defun intern-callback (name)
(intern (format nil "~A::~A"
(if-let (package (symbol-package name))
(package-name package)
"#")
(symbol-name name))
'#:cffi-callbacks)))
(defmacro %defcallback (name rettype arg-names arg-types body
Stelian Ionescu
committed
&key convention)
(declare (ignore convention))
(let ((cb-name (intern-callback name)))
(ffi:defcallback (,cb-name :cdecl)
(setf (gethash ',name *callbacks*) ',cb-name))))
(defun %callback (name)
(multiple-value-bind (symbol winp)
(gethash name *callbacks*)
(unless winp
(error "Undefined callback: ~S" name))
(defun %foreign-symbol-pointer (name library)
"Returns a pointer to a foreign symbol NAME."
(handler-case
(si:find-foreign-symbol name :default :pointer-void 0)
(error (c) nil)))