Commit | Line | Data |
---|---|---|
9d774814 GH |
1 | ;;; installed-scm-file |
2 | ||
6d36532c | 3 | ;;;; Copyright (C) 1997, 1999, 2000, 2001 Free Software Foundation, Inc. |
9d774814 | 4 | ;;;; |
73be1d9e MV |
5 | ;;;; This library is free software; you can redistribute it and/or |
6 | ;;;; modify it under the terms of the GNU Lesser General Public | |
7 | ;;;; License as published by the Free Software Foundation; either | |
8 | ;;;; version 2.1 of the License, or (at your option) any later version. | |
9d774814 | 9 | ;;;; |
73be1d9e | 10 | ;;;; This library is distributed in the hope that it will be useful, |
9d774814 | 11 | ;;;; but WITHOUT ANY WARRANTY; without even the implied warranty of |
73be1d9e MV |
12 | ;;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | ;;;; Lesser General Public License for more details. | |
9d774814 | 14 | ;;;; |
73be1d9e MV |
15 | ;;;; You should have received a copy of the GNU Lesser General Public |
16 | ;;;; License along with this library; if not, write to the Free Software | |
92205699 | 17 | ;;;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
9d774814 GH |
18 | ;;;; |
19 | \f | |
20 | ||
6d36532c GH |
21 | ;;; This is the Scheme part of the module for delimited I/O. It's |
22 | ;;; similar to (scsh rdelim) but somewhat incompatible. | |
9d774814 | 23 | |
1a179b03 MD |
24 | (define-module (ice-9 rdelim) |
25 | :export (read-line read-line! read-delimited read-delimited! | |
26 | %read-delimited! %read-line write-line) ; C | |
27 | ) | |
9d774814 | 28 | |
43fd4402 MV |
29 | (%init-rdelim-builtins) |
30 | ||
9d774814 GH |
31 | (define (read-line! string . maybe-port) |
32 | ;; corresponds to SCM_LINE_INCREMENTORS in libguile. | |
33 | (define scm-line-incrementors "\n") | |
34 | ||
35 | (let* ((port (if (pair? maybe-port) | |
36 | (car maybe-port) | |
37 | (current-input-port)))) | |
38 | (let* ((rv (%read-delimited! scm-line-incrementors | |
39 | string | |
40 | #t | |
41 | port)) | |
42 | (terminator (car rv)) | |
43 | (nchars (cdr rv))) | |
44 | (cond ((and (= nchars 0) | |
45 | (eof-object? terminator)) | |
46 | terminator) | |
47 | ((not terminator) #f) | |
48 | (else nchars))))) | |
49 | ||
50 | (define (read-delimited! delims buf . args) | |
51 | (let* ((num-args (length args)) | |
52 | (port (if (> num-args 0) | |
53 | (car args) | |
54 | (current-input-port))) | |
55 | (handle-delim (if (> num-args 1) | |
56 | (cadr args) | |
57 | 'trim)) | |
58 | (start (if (> num-args 2) | |
59 | (caddr args) | |
60 | 0)) | |
61 | (end (if (> num-args 3) | |
62 | (cadddr args) | |
63 | (string-length buf)))) | |
64 | (let* ((rv (%read-delimited! delims | |
65 | buf | |
66 | (not (eq? handle-delim 'peek)) | |
67 | port | |
68 | start | |
69 | end)) | |
70 | (terminator (car rv)) | |
71 | (nchars (cdr rv))) | |
72 | (cond ((or (not terminator) ; buffer filled | |
73 | (eof-object? terminator)) | |
74 | (if (zero? nchars) | |
75 | (if (eq? handle-delim 'split) | |
76 | (cons terminator terminator) | |
77 | terminator) | |
78 | (if (eq? handle-delim 'split) | |
79 | (cons nchars terminator) | |
80 | nchars))) | |
81 | (else | |
82 | (case handle-delim | |
83 | ((trim peek) nchars) | |
84 | ((concat) (string-set! buf (+ nchars start) terminator) | |
85 | (+ nchars 1)) | |
86 | ((split) (cons nchars terminator)) | |
87 | (else (error "unexpected handle-delim value: " | |
88 | handle-delim)))))))) | |
89 | ||
90 | (define (read-delimited delims . args) | |
91 | (let* ((port (if (pair? args) | |
92 | (let ((pt (car args))) | |
93 | (set! args (cdr args)) | |
94 | pt) | |
95 | (current-input-port))) | |
96 | (handle-delim (if (pair? args) | |
97 | (car args) | |
98 | 'trim))) | |
bf4aaed2 | 99 | (let loop ((substrings '()) |
9d774814 GH |
100 | (total-chars 0) |
101 | (buf-size 100)) ; doubled each time through. | |
102 | (let* ((buf (make-string buf-size)) | |
103 | (rv (%read-delimited! delims | |
104 | buf | |
105 | (not (eq? handle-delim 'peek)) | |
106 | port)) | |
107 | (terminator (car rv)) | |
108 | (nchars (cdr rv)) | |
109 | (join-substrings | |
110 | (lambda () | |
111 | (apply string-append | |
112 | (reverse | |
113 | (cons (if (and (eq? handle-delim 'concat) | |
114 | (not (eof-object? terminator))) | |
115 | (string terminator) | |
116 | "") | |
117 | (cons (substring buf 0 nchars) | |
118 | substrings)))))) | |
119 | (new-total (+ total-chars nchars))) | |
120 | (cond ((not terminator) | |
121 | ;; buffer filled. | |
122 | (loop (cons (substring buf 0 nchars) substrings) | |
123 | new-total | |
124 | (* buf-size 2))) | |
125 | ((eof-object? terminator) | |
126 | (if (zero? new-total) | |
127 | (if (eq? handle-delim 'split) | |
128 | (cons terminator terminator) | |
129 | terminator) | |
130 | (if (eq? handle-delim 'split) | |
131 | (cons (join-substrings) terminator) | |
132 | (join-substrings)))) | |
133 | (else | |
134 | (case handle-delim | |
135 | ((trim peek concat) (join-substrings)) | |
136 | ((split) (cons (join-substrings) terminator)) | |
137 | ||
138 | ||
139 | (else (error "unexpected handle-delim value: " | |
140 | handle-delim))))))))) | |
141 | ||
142 | ;;; read-line [PORT [HANDLE-DELIM]] reads a newline-terminated string | |
143 | ;;; from PORT. The return value depends on the value of HANDLE-DELIM, | |
144 | ;;; which may be one of the symbols `trim', `concat', `peek' and | |
145 | ;;; `split'. If it is `trim' (the default), the trailing newline is | |
146 | ;;; removed and the string is returned. If `concat', the string is | |
147 | ;;; returned with the trailing newline intact. If `peek', the newline | |
148 | ;;; is left in the input port buffer and the string is returned. If | |
149 | ;;; `split', the newline is split from the string and read-line | |
150 | ;;; returns a pair consisting of the truncated string and the newline. | |
151 | ||
152 | (define (read-line . args) | |
153 | (let* ((port (if (null? args) | |
154 | (current-input-port) | |
155 | (car args))) | |
156 | (handle-delim (if (> (length args) 1) | |
157 | (cadr args) | |
158 | 'trim)) | |
159 | (line/delim (%read-line port)) | |
160 | (line (car line/delim)) | |
161 | (delim (cdr line/delim))) | |
162 | (case handle-delim | |
163 | ((trim) line) | |
164 | ((split) line/delim) | |
165 | ((concat) (if (and (string? line) (char? delim)) | |
166 | (string-append line (string delim)) | |
167 | line)) | |
168 | ((peek) (if (char? delim) | |
169 | (unread-char delim port)) | |
170 | line) | |
171 | (else | |
172 | (error "unexpected handle-delim value: " handle-delim))))) |