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
|
;;; c-snarf.scm -- Parsing documentation "snarffed" from C files.
;;;
;;; Copyright 2006-2012 Free Software Foundation, Inc.
;;;
;;;
;;; This program is free software; you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or
;;; (at your option) any later version.
;;;
;;; This program 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 General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program; if not, write to the Free Software
;;; Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
(define-module (system documentation c-snarf)
:use-module (ice-9 popen)
:use-module (ice-9 rdelim)
:use-module (srfi srfi-13)
:use-module (srfi srfi-14)
:use-module (srfi srfi-39)
:export (run-cpp-and-extract-snarfing
parse-snarfing
parse-snarfed-line))
;;; Author: Ludovic Court�s
;;;
;;; Commentary:
;;;
;;; This module provides tools to parse and otherwise manipulate
;;; documentation "snarffed" from C files, i.e., information obtained by
;;; running the C preprocessor with the @code{-DSCM_MAGIC_SNARF_DOCS} flag.
;;;
;;; Code:
;;;
;;; High-level API.
;;;
(define (run-cpp-and-extract-snarfing file cpp cpp-flags)
(let ((pipe (apply open-pipe* OPEN_READ
(cons cpp (append cpp-flags (list file))))))
(parse-snarfing pipe)))
;;;
;;; Parsing magic-snarffed CPP output.
;;;
(define (parse-c-argument-list arg-string)
"Parse @var{arg-string} (a string representing a ANSI C argument list,
e.g., @var{(const SCM first, SCM second_arg)}) and return a list of strings
denoting the argument names."
(define %c-symbol-char-set
(char-set-adjoin char-set:letter+digit #\_))
(let loop ((args (string-tokenize (string-trim-both arg-string #\space)
%c-symbol-char-set))
(type? #t)
(result '()))
(if (null? args)
(reverse! result)
(let ((the-arg (car args)))
(cond ((and type? (string=? the-arg "const"))
(loop (cdr args) type? result))
((and type? (string=? the-arg "SCM"))
(loop (cdr args) (not type?) result))
(type? ;; any other type, e.g., `void'
(loop (cdr args) (not type?) result))
(else
(loop (cdr args) (not type?) (cons the-arg result))))))))
(define (parse-documentation-item item)
"Parse @var{item} (a string), a single function string produced by the C
preprocessor. The result is an alist whose keys represent specific aspects
of a procedure's documentation: @code{c-name}, @code{scheme-name},
@code{documentation} (a Texinfo documentation string), etc."
(define (read-strings)
;; Read several subsequent strings and return their concatenation.
(let loop ((str (read))
(result '()))
(if (or (eof-object? str)
(not (string? str)))
(string-concatenate (reverse! result))
(loop (read) (cons str result)))))
(let* ((item (string-trim-both item #\space))
(space (string-index item #\space)))
(if (not space)
(error "invalid documentation item" item)
(let ((kind (substring item 0 space))
(rest (substring item space (string-length item))))
(cond ((string=? kind "cname")
(cons 'c-name (string-trim-both rest #\space)))
((string=? kind "fname")
(cons 'scheme-name
(with-input-from-string rest read-strings)))
((string=? kind "type")
(cons 'type (with-input-from-string rest read)))
((string=? kind "location")
(cons 'location
(with-input-from-string rest
(lambda ()
(let loop ((str (read))
(result '()))
(if (eof-object? str)
(reverse! result)
(loop (read) (cons str result))))))))
((string=? kind "arglist")
(cons 'arguments
(parse-c-argument-list rest)))
((string=? kind "argsig")
(cons 'signature
(with-input-from-string rest
(lambda ()
(let ((req (read)) (opt (read)) (rst? (read)))
(list (cons 'required req)
(cons 'optional opt)
(cons 'rest? (= 1 rst?))))))))
(else
;; docstring (may consist of several C strings which we
;; assume to be equivalent to Scheme strings)
(cons 'documentation
(with-input-from-string item read-strings))))))))
(define (parse-snarfed-line line)
"Parse @var{line}, a string that contains documentation returned for a
single function by the C preprocessor with the @code{-DSCM_MAGIC_SNARF_DOCS}
option. @var{line} is assumed to be a complete \"^^ { ... ^^ }\" sequence."
(define (caret-split str)
(let loop ((str str)
(result '()))
(if (string=? str "")
(reverse! result)
(let ((caret (string-index str #\^))
(len (string-length str)))
(if caret
(if (and (> (- len caret) 0)
(eq? (string-ref str (+ caret 1)) #\^))
(loop (substring str (+ 2 caret) len)
(cons (string-take str (- caret 1)) result))
(error "single caret not allowed" str))
(loop "" (cons str result)))))))
(let ((items (caret-split (substring line 4
(- (string-length line) 4)))))
(map parse-documentation-item items)))
(define (parse-snarfing port)
"Read C preprocessor (where the @code{SCM_MAGIC_SNARF_DOCS} macro is
defined) output from @var{port} a return a list of alist, each of which
contains information about a specific function described in the C
preprocessor output."
(define start-marker "^^ {")
(define end-marker "^^ }")
(define (read-snarf-lines start)
;; Read the snarf lines that follow START until and end marker is found.
(let loop ((line start)
(result '()))
(cond ((eof-object? line)
;; EOF in the middle of a "^^ { ... ^^ }" sequence; shouldn't
;; happen.
line)
((string-contains line end-marker)
=>
(lambda (end)
(let ((result (cons (string-take line (+ 3 end))
result)))
(string-concatenate-reverse result))))
((string-prefix? "#" line)
;; Presumably a "# LINENUM" directive; skip it.
(loop (read-line port) result))
(else
(loop (read-line port)
(cons line result))))))
(let loop ((line (read-line port))
(result '()))
(cond ((eof-object? line)
result)
((string-contains line start-marker)
=>
(lambda (start)
(let ((line
(read-snarf-lines (string-drop line start))))
(loop (read-line port)
(cons (parse-snarfed-line line) result)))))
(else
(loop (read-line port) result)))))
;;; c-snarf.scm ends here
;;; Local Variables:
;;; mode: scheme
;;; coding: latin-1
;;; End:
;;; arch-tag: dcba2446-ee43-46d8-a47e-e6e12f121988
|
