;;;; foreign.test --- FFI.           -*- mode: scheme; coding: utf-8; -*-
;;;;
;;;; 	Copyright (C) 2010 Free Software Foundation, Inc.
;;;;
;;;; This library is free software; you can redistribute it and/or
;;;; modify it under the terms of the GNU Lesser General Public
;;;; License as published by the Free Software Foundation; either
;;;; version 3 of the License, or (at your option) any later version.
;;;;
;;;; This library is distributed in the hope that it will be useful,
;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;;; Lesser General Public License for more details.
;;;;
;;;; You should have received a copy of the GNU Lesser General Public
;;;; License along with this library; if not, write to the Free Software
;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

;;;
;;; See also ../standalone/test-ffi for FFI tests.
;;;

(define-module (test-foreign)
  #:use-module (system foreign)
  #:use-module (rnrs bytevectors)
  #:use-module (srfi srfi-1)
  #:use-module (srfi srfi-26)
  #:use-module (test-suite lib))


(with-test-prefix "null pointer"

  (pass-if "zero"
    (= 0 (pointer-address %null-pointer)))

  (pass-if "null pointer identity"
    (eq? %null-pointer (make-pointer 0)))

  (pass-if "null-pointer? %null-pointer"
    (null-pointer? %null-pointer))

  (pass-if-exception "pointer->bytevector %null-pointer"
    exception:null-pointer-error
    (pointer->bytevector %null-pointer 7)))


(with-test-prefix "make-pointer"

  (pass-if "address preserved"
    (= 123 (pointer-address (make-pointer 123))))

  (pass-if "equal?"
    (equal? (make-pointer 123) (make-pointer 123)))

  (pass-if "equal? modulo finalizer"
    (let ((finalizer (dynamic-func "scm_is_pair" (dynamic-link))))
      (equal? (make-pointer 123)
              (make-pointer 123 finalizer))))

  (pass-if "not equal?"
    (not (equal? (make-pointer 123) (make-pointer 456)))))


(with-test-prefix "pointer<->bytevector"

  (pass-if "bijection"
    (let ((bv #vu8(0 1 2 3 4 5 6 7)))
      (equal? (pointer->bytevector (bytevector->pointer bv)
                                   (bytevector-length bv))
              bv)))

  (pass-if "pointer from bits"
    (let* ((bytes (iota (sizeof '*)))
           (bv    (u8-list->bytevector bytes)))
      (= (pointer-address
          (make-pointer (bytevector-uint-ref bv 0 (native-endianness)
                                             (sizeof '*))))
         (fold-right (lambda (byte address)
                       (+ byte (* 256 address)))
                     0
                     bytes))))

  (pass-if "dereference-pointer"
    (let* ((bytes (iota (sizeof '*)))
           (bv    (u8-list->bytevector bytes)))
      (= (pointer-address
          (dereference-pointer (bytevector->pointer bv)))
         (fold-right (lambda (byte address)
                       (+ byte (* 256 address)))
                     0
                     bytes)))))


(with-test-prefix "pointer<->string"

  (pass-if "bijection"
    (let ((s "hello, world"))
      (string=? s (pointer->string (string->pointer s)))))

  (pass-if "bijection [latin1]"
    (with-latin1-locale
      (let ((s "Szép jó napot!"))
        (string=? s (pointer->string (string->pointer s)))))))


(with-test-prefix "procedure->pointer"

  (define qsort
    ;; Bindings for libc's `qsort' function.
    (pointer->procedure void
                        (dynamic-func "qsort" (dynamic-link))
                        (list '* size_t size_t '*)))

  (define (dereference-pointer-to-byte ptr)
    (let ((b (pointer->bytevector ptr 1)))
      (bytevector-u8-ref b 0)))

  (define input
    '(7 1 127 3 5 4 77 2 9 0))

  (pass-if "qsort"
    (if (defined? 'procedure->pointer)
        (let* ((called? #f)
               (cmp     (lambda (x y)
                          (set! called? #t)
                          (- (dereference-pointer-to-byte x)
                             (dereference-pointer-to-byte y))))
               (ptr     (procedure->pointer int cmp (list '* '*)))
               (bv      (u8-list->bytevector input)))
          (qsort (bytevector->pointer bv) (bytevector-length bv) 1
                 (procedure->pointer int cmp (list '* '*)))
          (and called?
               (equal? (bytevector->u8-list bv)
                       (sort input <))))
        (throw 'unresolved)))

  (pass-if-exception "qsort, wrong return type"
    exception:wrong-type-arg

    (if (defined? 'procedure->pointer)
        (let* ((cmp     (lambda (x y) #f)) ; wrong return type
               (ptr     (procedure->pointer int cmp (list '* '*)))
               (bv      (u8-list->bytevector input)))
          (qsort (bytevector->pointer bv) (bytevector-length bv) 1
                 (procedure->pointer int cmp (list '* '*)))
          #f)
        (throw 'unresolved)))

  (pass-if-exception "qsort, wrong arity"
    exception:wrong-num-args

    (if (defined? 'procedure->pointer)
        (let* ((cmp     (lambda (x y z) #f)) ; wrong arity
               (ptr     (procedure->pointer int cmp (list '* '*)))
               (bv      (u8-list->bytevector input)))
          (qsort (bytevector->pointer bv) (bytevector-length bv) 1
                 (procedure->pointer int cmp (list '* '*)))
          #f)
        (throw 'unresolved)))

  (pass-if "bijection"
    (if (defined? 'procedure->pointer)
        (let* ((proc  (lambda (x y z)
                        (+ x y z 0.0)))
               (ret   double)
               (args  (list float int16 double))
               (proc* (pointer->procedure ret
                                          (procedure->pointer ret proc args)
                                          args))
               (arg1  (map (cut / <> 2.0) (iota 123)))
               (arg2  (iota 123 32000))
               (arg3  (map (cut / <> 4.0) (iota 123 100 4))))
          (equal? (map proc arg1 arg2 arg3)
                  (map proc* arg1 arg2 arg3)))
        (throw 'unresolved))))


(with-test-prefix "structs"

  (pass-if "sizeof { int8, double }"
    (= (sizeof (list int8 double))
       (+ (alignof double) (sizeof double))))

  (pass-if "sizeof { short, int, long, pointer }"
    (let ((layout (list short int long '*)))
      (>= (sizeof layout)
          (reduce + 0.0 (map sizeof layout)))))

  (pass-if "parse-c-struct"
    (let ((layout (list int64 uint8))
          (data   (list -300 43)))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data)))

  (pass-if "alignment constraints honored"
    (let ((layout (list int8 double))
          (data   (list -7 3.14)))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data)))

  (pass-if "int8, pointer"
    (let ((layout (list uint8 '*))
          (data   (list 222 (make-pointer 7777))))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data)))

  (pass-if "unsigned-long, int8, size_t"
    (let ((layout (list unsigned-long int8 size_t))
          (data   (list (expt 2 17) -128 (expt 2 18))))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data)))

  (pass-if "long, int, pointer"
    (let ((layout (list long int '*))
          (data   (list (- (expt 2 17)) -222 (make-pointer 777))))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data)))

  (pass-if "int8, pointer, short, double"
    (let ((layout (list int8 '* short double))
          (data   (list 77 %null-pointer -42 3.14)))
      (equal? (parse-c-struct (make-c-struct layout data)
                              layout)
              data))))