1;;; File input/output utilities
2
3;; Copyright (C) 2004 Brailcom, o.p.s.
4
5;; Author: Milan Zamazal <pdm@brailcom.org>
6
7;; COPYRIGHT NOTICE
8
9;; This program is free software; you can redistribute it and/or modify
10;; it under the terms of the GNU General Public License as published by
11;; the Free Software Foundation; either version 2 of the License, or
12;; (at your option) any later version.
13
14;; This program is distributed in the hope that it will be useful, but
15;; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
16;; or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
17;; for more details.
18
19;; You should have received a copy of the GNU General Public License
20;; along with this program; if not, write to the Free Software
21;; Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
22
23
24(require 'util)
25
26
27(defmac (with-open-file form)
28  (let* ((spec (nth 1 form))
29         (body (nth_cdr 2 form))
30         (var (nth 0 spec))
31         (filename (nth 1 spec))
32         (how (or (nth 2 spec) "r")))
33    `(let ((,var (fopen ,filename ,how)))
34       (unwind-protect* (begin ,@body)
35         (fclose ,var)))))
36
37(defmac (with-temp-file-data form)
38  (let* ((spec (nth 1 form))
39         (body (nth_cdr 2 form))
40         (filename (nth 0 spec))
41         (data (nth 1 spec)))
42    `(with-temp-file ,filename
43       (write-file ,filename ,data)
44       ,@body)))
45
46(define (write-file filename string)
47  (with-open-file (f filename "w")
48    (fwrite (if (symbol? string) (format nil "%s" string) string) f)))
49
50(define (read-file filename)
51  (with-open-file (f filename)
52    (let* ((strings '())
53           (buffer (format nil "%1024s" ""))
54           (buflen (length buffer))
55           (n 0)
56           (reading t))
57      (while reading
58        (set! n (fread buffer f))
59        (if n
60            (begin
61              (push (substring buffer 0 n) strings)
62              (when (< n buflen)
63                (set! reading nil)))
64            (set! reading nil)))
65      (apply string-append (reverse strings)))))
66
67(define (make-read-line-state)
68  (list ""))
69
70(define (read-line file state)
71  (let* ((text (car state))
72         (line (and text (string-before text "\n"))))
73    (cond
74     ((not text)
75      nil)
76     ((equal? line "")
77      (let* ((buffer (format nil "%256s" ""))
78             (n (fread buffer file)))
79        (cond
80         ((and (not n) (eqv? text ""))
81          (set! line nil)
82          (set! text nil))
83         ((not n)
84          (set! line text)
85          (set! text nil))
86         (t
87          (set! text (string-append text (substring buffer 0 n)))
88          (let ((state* (list text)))
89            (set! line (read-line file state*))
90            (set! text (car state*)))))))
91     (t
92      (set! text (string-after text "\n"))))
93    (set-car! state text)
94    line))
95
96
97(provide 'fileio)
98