1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
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
|
;;; C declaration compiler.
;* Copyright (c) 1989-1993 Hewlett-Packard Development Company, L.P.
;* All Rights Reserved
;* 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.
;;; This module compiles "extern" forms which define C library procedures.
;;;
;;; <extern> ::= ( EXTERN <type> <fname> [ <arg> ... ] )
;;;
;;; <fname> ::= a Scheme string
;;;
;;; <arg> ::= ( <type> <id> )
;;; ( IN <type> <id> )
;;; ( OUT <type> <id> )
;;; ( IN_OUT <type> <id> )
;;;
;;; <id> ::= a Scheme symbol
(module extern)
;;; The following function syntax checks an extern expression. It will either
;;; report an error, or return the expression as its value.
(define (INPUT-EXTERN exp)
(if (and (>= (length exp) 3)
(parse-type (cadr exp))
(string? (caddr exp)))
(begin (for-each parse-arg (cdddr exp))
exp)
(error 'input-extern "Illegal EXTERN syntax: ~s" exp)))
;;; Parses the argument list and calls error on an error.
(define (PARSE-ARG exp)
(if (and (pair? exp)
(or (and (= (length exp) 2)
(parse-type (car exp))
(symbol? (cadr exp)))
(and (= (length exp) 3)
(memq (car exp) '(in out in_out))
(parse-type (cadr exp))
(symbol? (caddr exp)))))
#t
(error 'PARSE-ARG "Illegal ARGUMENT syntax: ~s" exp)))
;;; Code is generated by the following function.
(define (EMIT-EXTERNS externs extern-file-root type-file-root)
(let ((module (uis extern-file-root)))
(with-output-to-file
(string-append extern-file-root ".sc")
(lambda ()
(write `(module ,module))
(newline)
(write `(include ,(string-append type-file-root ".sch")))
(newline)
(for-each (lambda (x) (emit-extern x 'define)) externs)))
(with-output-to-file
(string-append extern-file-root ".sch")
(lambda ()
(for-each (lambda (x) (emit-define-external x module))
externs)))))
;;; The definition for the interface procedure for an extern is created by
;;; the following procedure.
(define (EMIT-EXTERN extern defform)
(let ((xname (uis (caddr extern) "*"))
(rettype (cadr extern))
(args (cdddr extern)))
(define (EMIT-CALL)
`(,xname ,@(map (lambda (x) (car (last-pair x))) args)))
(define (FORMALS args)
(if args
(if (eq? (caar args) 'out)
(formals (cdr args))
(cons (car (last-pair (car args)))
(formals (cdr args))))
'()))
(pp `(define-c-external
(,xname ,@(map simple-type args))
,(simple-type (list rettype 'returned))
,(caddr extern)))
(newline)
(pp `(,defform (,(uis (caddr extern)) ,@(formals args))
(let* (,@(map arg-in args)
(return-value
,(cond ((eq? rettype 'void)
`(begin ,(emit-call) #f))
((eq? rettype 'string)
`(c-string->string ,(emit-call)))
((isa-pointer? rettype)
`(cons ',(base-type rettype)
,(emit-call)))
(else (emit-call)))))
,(let ((out (args-out args)))
(if out
(if (eq? rettype 'void)
(if (= (length out) 1)
(car out)
`(list ,@out))
`(list return-value ,@out))
'return-value)))))
(newline)))
;;; Called to do input conversion for arguments. Return an expression
;;; of th form (<var> <value>).
(define (ARG-IN arg)
(let* ((flag (if (memq (car arg) '(in out in_out))
(car arg)
#f))
(type (if flag (cadr arg) (car arg)))
(var (if flag (caddr arg) (cadr arg))))
(case flag
((in in_out) (cond ((eq? (base-type type) 'int)
`(,var (let ((_buf (make-string
,(size-of 'int))))
(c-int-set! _buf 0 ,var)
_buf)))
(else `(,var (in->c ,var)))))
((out) `(,var (make-string ,(if (eq? type 'string)
(size-of 'pointer)
(aligned-size-of type)))))
(else (cond ((eq? type 'string)
`(,var (if (string? ,var)
,var
(error 'chk-string
"Argument is incorrect type: ~s"
,var))))
((isa-pointer? type)
`(,var (,(uis "CHK-" (base-type type)) ,var)))
(else `(,var ,var)))))))
;;; Return a list of the expressions required to do output conversion after
;;; an external call.
(define (ARGS-OUT args)
(define (ARG-OUT arg)
(let* ((flag (if (memq (car arg) '(in out in_out))
(car arg)
#f))
(type (if flag (cadr arg) (car arg)))
(var (if flag (caddr arg) (cadr arg))))
(case flag
((in) #f)
((in_out out)
(cond ((eq? type 'string)
`(c-string->string (c-unsigned-ref ,var 0)))
((isa-pointer? type)
`(cons ',(base-type type)
(c-unsigned-ref ,var 0)))
((or (isa-union? type) (isa-struct? type)
(isa-array? type))
`(cons ',(pointed-to-by type) ,var))
(else `(,(getprop (base-type type) 'to-get)
,var 0))))
(else #f))))
(if args
(let ((out (arg-out (car args))))
(if out
(cons out (args-out (cdr args)))
(args-out (cdr args))))
'()))
;;; Converts the type of a procedure argument to a simple C-type.
(define (SIMPLE-TYPE type)
(cond ((memq (car type) '(in out in_out string)) 'pointer)
((eq? (car type) 'void) 'void)
((isa-pointer? (car type)) 'pointer)
((isa-procp? (car type)) 'pointer)
(else (base-type (car type)))))
;;; The STUBS file is written by the following function.
(define (EMIT-STUBS externs stubs-file-root)
(with-output-to-file
(string-append stubs-file-root ".sc")
(lambda ()
(write `(module ,(uis stubs-file-root)))
(newline)
(for-each emit-stub externs))))
;;; The external definition for a procedure is written by the following
;;; function.
(define (EMIT-DEFINE-EXTERNAL extern module)
(let ((formals (let loop ((args (cdddr extern))
(formals '(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)))
(cond ((null? args) '())
((eq? (caar args) 'out)
(loop (cdr args) (cdr formals)))
(else (cons (car formals)
(loop (cdr args) (cdr formals))))))))
(pp `(define-external (,(uis (caddr extern)) ,@formals) ,module))
(newline)))
;;; The definition for a stub procedure is written by the following function.
(define (EMIT-STUB extern)
(let* ((c-name (uis (caddr extern) "**"))
(stub-name (uis (caddr extern) "*"))
(rettype (cadr extern))
(args (cdddr extern))
(formals (let loop ((args args)
(formals '(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)))
(if (not (null? args))
(cons (car formals)
(loop (cdr args) (cdr formals)))
'()))))
(pp `(define-c-external
(,c-name ,@(map simple-type args))
,(simple-type (list rettype 'returned))
,(caddr extern)))
(newline)
(pp `(define (,stub-name ,@formals)
(,c-name ,@formals)
,@(if (eq? rettype 'void) '(#f) '())))
(newline)))
|
