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
|
; Copyright (c) 1993-2008 by Richard Kelsey and Jonathan Rees. See file COPYING.
; Exports:
; make-regexp
; regexp?
; regexp-match
; regexp-match?
; regexp-match-start
; regexp-match-end
; regexp-option
(import-dynamic-externals "=scheme48external/posix")
; The compiled version of the expression is produced when needed.
(define-record-type regexp :regexp
(really-make-regexp pattern pattern-byte-string
compiled
extended? ignore-case? submatches? newline?)
regexp?
(pattern regexp-pattern) ; immutable string
(pattern-byte-string regexp-pattern-byte-string)
(compiled real-regexp-compiled set-regexp-compiled!) ; #f or a c-record
(extended? regexp-extended?) ; four flags
(ignore-case? regexp-ignore-case?)
(submatches? regexp-submatches?)
(newline? regexp-newline?))
; Drop the compiled version when resuming. We may be resuming on a different
; architecture, or version of the library, or whatever.
(define-record-resumer :regexp
(lambda (regexp)
(set-regexp-compiled! regexp #f)))
; There are four options when making a regular expression.
(define-enumerated-type regexp-option :regexp-option
regexp-option?
regexp-options
regexp-option-name
regexp-option-index
(extended ignore-case submatches newline))
; Loop down finding which options are present and checking for duplicates.
; This is not specific to regular expressions.
;
; It would be nice if this could handle values as well, as in
; (make-regexp "sldkjf" (regexp-option size 10))
(define (decode-boolean-options options all-options predicate indexer)
(let ((map (make-vector (vector-length all-options) #f)))
(let loop ((options options))
(if (null? options)
(vector->list map)
(let ((option (car options)))
(if (predicate option)
(let ((index (indexer option)))
(if (vector-ref map index)
'duplicates
(begin
(vector-set! map index #t)
(loop (cdr options)))))
'bad-value))))))
; The only thing we do here is to decode the options and make sure that the
; pattern is immutable, as it won't be used until later.
(define (make-regexp pattern . options)
(let ((options (decode-boolean-options options
regexp-options
regexp-option?
regexp-option-index)))
(if (and (string? pattern)
(pair? options))
(let* ((pattern (string->immutable-string pattern))
(pattern-byte-string (string->byte-vector pattern))
(regexp (apply really-make-regexp pattern pattern-byte-string #f options)))
(add-finalizer! regexp free-compiled-regexp)
regexp)
(apply call-error "invalid argument(s)"
make-regexp
pattern
options))))
; Free up the C-heap storage used for the compiled regexp.
(define (free-compiled-regexp regexp)
(let ((compiled (real-regexp-compiled regexp)))
(if compiled
(call-imported-binding posix-free-regexp compiled))))
; We compile the pattern if that hasn't already been done, raising an error
; if anything goes wrong.
(define (regexp-compiled regexp)
(or (real-regexp-compiled regexp)
(let ((compiled (call-imported-binding posix-compile-regexp
(regexp-pattern-byte-string regexp)
(regexp-extended? regexp)
(regexp-ignore-case? regexp)
(regexp-submatches? regexp)
(regexp-newline? regexp))))
(if (not (integer? compiled))
(begin
(set-regexp-compiled! regexp compiled)
compiled)
(let ((message (call-imported-binding posix-regexp-error-message
(regexp-pattern-byte-string regexp)
(regexp-extended? regexp)
(regexp-ignore-case? regexp)
(regexp-submatches? regexp)
(regexp-newline? regexp))))
(error (if message
(string-append "Posix regexp: " message)
"inconsistent results from Posix regexp compiler")
regexp))))))
; Call the pattern matcher. We return #F if the match fails. On a successful
; match, we either return #T or a list of match records, depending on the value
; of SUBMATCHES?.
(define (regexp-match regexp string start submatches? starts-line? ends-line?)
(cond
((not (and (regexp? regexp)
(string? string)))
(call-error "invalid argument"
regexp-match
regexp string start starts-line? ends-line?))
((and submatches?
(not (regexp-submatches? regexp)))
(call-error "regexp not compiled for submatches"
regexp-match
regexp string start starts-line? ends-line?))
(else
(call-imported-binding posix-regexp-match
(regexp-compiled regexp)
(string->byte-vector string)
start
submatches?
starts-line?
ends-line?))))
; we can't do any better with POSIX, Mike thinks
(define (string->byte-vector s)
(os-string->byte-vector
(call-with-os-string-text-codec
latin-1-codec
(lambda ()
(string->os-string s)))))
; These are made by the C code. The SUBMATCHES field is not used by us,
; but is used by the functional interface.
(define-record-type match :match
(make-match start end submatches)
match?
(start match-start)
(end match-end)
(submatches match-submatches))
(define-record-discloser :match
(lambda (rem)
(list 'match
(match-start rem)
(match-end rem))))
(define-exported-binding "posix-regexp-match-type" :match)
; The various C functions we use.
(import-definition posix-compile-regexp)
(import-definition posix-regexp-match)
(import-definition posix-regexp-error-message)
(import-definition posix-free-regexp)
|
