1 /* $NetBSD: fold.c,v 1.17 2011/09/04 20:24:59 joerg Exp $ */
2
3 /*-
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kevin Ruddy.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 #ifndef lint
37 __COPYRIGHT("@(#) Copyright (c) 1990, 1993\
38 The Regents of the University of California. All rights reserved.");
39 #endif /* not lint */
40
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "@(#)fold.c 8.1 (Berkeley) 6/6/93";
44 #endif
45 __RCSID("$NetBSD: fold.c,v 1.17 2011/09/04 20:24:59 joerg Exp $");
46 #endif /* not lint */
47
48 #include <limits.h>
49 #include <locale.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <unistd.h>
53 #include <wchar.h>
54 #include <err.h>
55
56 #define DEFLINEWIDTH 80
57
58 static void fold(int);
59 static int new_column_position(int, wint_t);
60 __dead static void usage(void);
61
62 static int count_bytes = 0;
63 static int split_words = 0;
64
65 int
main(int argc,char ** argv)66 main(int argc, char **argv)
67 {
68 int ch;
69 int width;
70 char *p;
71
72 setlocale(LC_CTYPE, "");
73 setprogname(argv[0]);
74
75 width = -1;
76 while ((ch = getopt(argc, argv, "0123456789bsw:")) != -1)
77 switch (ch) {
78 case 'b':
79 count_bytes = 1;
80 break;
81 case 's':
82 split_words = 1;
83 break;
84 case 'w':
85 if ((width = atoi(optarg)) <= 0)
86 errx(1, "illegal width value");
87 break;
88 case '0': case '1': case '2': case '3': case '4':
89 case '5': case '6': case '7': case '8': case '9':
90 if (width == -1) {
91 p = argv[optind - 1];
92 if (p[0] == '-' && p[1] == ch && !p[2])
93 width = atoi(++p);
94 else
95 width = atoi(argv[optind] + 1);
96 }
97 break;
98 default:
99 usage();
100 }
101 argv += optind;
102 argc -= optind;
103
104 if (width == -1)
105 width = DEFLINEWIDTH;
106
107 if (!*argv)
108 fold(width);
109 else for (; *argv; ++argv)
110 if (!freopen(*argv, "r", stdin)) {
111 err (1, "%s", *argv);
112 /* NOTREACHED */
113 } else
114 fold(width);
115 exit(0);
116 }
117
118 /*
119 * Fold the contents of standard input to fit within WIDTH columns
120 * (or bytes) and write to standard output.
121 *
122 * If split_words is set, split the line at the last space character
123 * on the line. This flag necessitates storing the line in a buffer
124 * until the current column > width, or a newline or EOF is read.
125 *
126 * The buffer can grow larger than WIDTH due to backspaces and carriage
127 * returns embedded in the input stream.
128 */
129 static void
fold(int width)130 fold(int width)
131 {
132 static wchar_t *buf = NULL;
133 wchar_t *nbuf;
134 static int buf_max = 0;
135 wint_t ch;
136 int col, indx, i;
137
138 col = indx = 0;
139 while ((ch = getwchar()) != WEOF) {
140 if (ch == L'\n') {
141 if (indx != 0) {
142 for (i = 0; i < indx; i++)
143 putwchar(buf[i]);
144 }
145 putwchar(L'\n');
146 col = indx = 0;
147 continue;
148 }
149
150 col = new_column_position (col, ch);
151 if (col > width) {
152 int last_space;
153
154 #ifdef __GNUC__
155 last_space = 0; /* XXX gcc */
156 #endif
157 if (split_words) {
158 for (i = 0, last_space = -1; i < indx; i++)
159 if (buf[i] == L' ')
160 last_space = i;
161 }
162
163 if (split_words && last_space != -1) {
164 for (i = 0; i < last_space; i++)
165 putwchar(buf[i]);
166
167 /* increase last_space here, so we skip trailing whitespace */
168 last_space++;
169 wmemmove (buf, buf+last_space, indx-last_space);
170
171 indx -= last_space;
172 col = 0;
173 for (i = 0; i < indx; i++) {
174 col = new_column_position (col, buf[i]);
175 }
176 } else {
177 for (i = 0; i < indx; i++)
178 putwchar(buf[i]);
179 col = indx = 0;
180 }
181 putwchar('\n');
182
183 /* calculate the column position for the next line. */
184 col = new_column_position (col, ch);
185 }
186
187 if (indx + 1 > buf_max) {
188 /* Allocate buffer in LINE_MAX increments */
189 if ((nbuf = realloc (buf, buf_max + 2048)) == NULL) {
190 err (1, "realloc");
191 /* NOTREACHED */
192 }
193 buf = nbuf;
194 buf_max += 2048;
195 }
196 buf[indx++] = ch;
197 }
198
199 if (indx != 0) {
200 for (i = 0; i < indx; i++)
201 putwchar(buf[i]);
202 }
203 }
204
205 /*
206 * calculate the column position
207 */
208 static int
new_column_position(int col,wint_t ch)209 new_column_position (int col, wint_t ch)
210 {
211 int w;
212
213 if (!count_bytes) {
214 switch (ch) {
215 case L'\b':
216 if (col > 0)
217 --col;
218 break;
219 case L'\r':
220 col = 0;
221 break;
222 case L'\t':
223 col = (col + 8) & ~7;
224 break;
225 default:
226 w = wcwidth(ch);
227 if (w > 0)
228 col += w;
229 break;
230 }
231 } else {
232 char dummy[MB_LEN_MAX];
233
234 /* XXX: we assume stateless encoding */
235 col += wcrtomb(dummy, ch, NULL);
236 }
237
238 return col;
239 }
240
241 static void
usage(void)242 usage(void)
243 {
244 (void)fprintf(stderr,
245 "usage: %s [-bs] [-w width] [file ...]\n", getprogname());
246 exit(1);
247 }
248
249