xref: /dragonfly/usr.bin/vis/vis.c (revision 0dbf214d)
1 /*-
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#) Copyright (c) 1989, 1993 The Regents of the University of California.  All rights reserved.
30  * @(#)vis.c	8.1 (Berkeley) 6/6/93
31  * $NetBSD: vis.c,v 1.25 2015/05/24 19:42:39 christos Exp $
32  */
33 
34 #include <stdio.h>
35 #include <string.h>
36 #include <stdlib.h>
37 #include <errno.h>
38 #include <wchar.h>
39 #include <limits.h>
40 #include <unistd.h>
41 #include <err.h>
42 #include <vis.h>
43 
44 #include "extern.h"
45 
46 static int eflags, fold, foldwidth = 80, none, markeol;
47 #ifdef DEBUG
48 int debug;
49 #endif
50 static const char *extra = "";
51 
52 static void process(FILE *);
53 
54 int
55 main(int argc, char *argv[])
56 {
57 	FILE *fp;
58 	int ch;
59 	int rval;
60 
61 	while ((ch = getopt(argc, argv, "bcde:F:fhlMmNnoSstw")) != -1)
62 		switch((char)ch) {
63 		case 'b':
64 			eflags |= VIS_NOSLASH;
65 			break;
66 		case 'c':
67 			eflags |= VIS_CSTYLE;
68 			break;
69 #ifdef DEBUG
70 		case 'd':
71 			debug++;
72 			break;
73 #endif
74 		case 'e':
75 			extra = optarg;
76 			break;
77 		case 'F':
78 			if ((foldwidth = atoi(optarg)) < 5) {
79 				errx(1, "can't fold lines to less than 5 cols");
80 			}
81 			markeol++;
82 			break;
83 		case 'f':
84 			fold++;		/* fold output lines to 80 cols */
85 			break;		/* using hidden newline */
86 		case 'h':
87 			eflags |= VIS_HTTPSTYLE;
88 			break;
89 		case 'l':
90 			markeol++;	/* mark end of line with \$ */
91 			break;
92 		case 'M':
93 			eflags |= VIS_META;
94 			break;
95 		case 'm':
96 			eflags |= VIS_MIMESTYLE;
97 			if (foldwidth == 80)
98 				foldwidth = 76;
99 			break;
100 		case 'N':
101 			eflags |= VIS_NOLOCALE;
102 			break;
103 		case 'n':
104 			none++;
105 			break;
106 		case 'o':
107 			eflags |= VIS_OCTAL;
108 			break;
109 		case 'S':
110 			eflags |= VIS_SHELL;
111 			break;
112 		case 's':
113 			eflags |= VIS_SAFE;
114 			break;
115 		case 't':
116 			eflags |= VIS_TAB;
117 			break;
118 		case 'w':
119 			eflags |= VIS_WHITE;
120 			break;
121 		case '?':
122 		default:
123 			fprintf(stderr,
124 			    "usage: %s [-bcfhlMmNnoSstw] [-e extra]"
125 			    " [-F foldwidth] [file ...]\n", getprogname());
126 			return 1;
127 		}
128 
129 	if ((eflags & (VIS_HTTPSTYLE|VIS_MIMESTYLE)) ==
130 	    (VIS_HTTPSTYLE|VIS_MIMESTYLE))
131 		errx(1, "Can't specify -m and -h at the same time");
132 
133 	argc -= optind;
134 	argv += optind;
135 
136 	rval = 0;
137 
138 	if (*argv)
139 		while (*argv) {
140 			if ((fp = fopen(*argv, "r")) != NULL) {
141 				process(fp);
142 				fclose(fp);
143 			} else {
144 				warn("%s", *argv);
145 				rval = 1;
146 			}
147 			argv++;
148 		}
149 	else
150 		process(stdin);
151 	return rval;
152 }
153 
154 static void
155 process(FILE *fp)
156 {
157 	static int col = 0;
158 	static char nul[] = "\0";
159 	char *cp = nul + 1;	/* so *(cp-1) starts out != '\n' */
160 	wint_t c, c1, rachar;
161 	char mbibuff[2 * MB_LEN_MAX + 1]; /* max space for 2 wchars */
162 	char buff[4 * MB_LEN_MAX + 1]; /* max encoding length for one char */
163 	int mbilen, cerr = 0, raerr = 0;
164 
165         /*
166          * The input stream is considered to be multibyte characters.
167          * The input loop will read this data inputing one character,
168 	 * possibly multiple bytes, at a time and converting each to
169 	 * a wide character wchar_t.
170          *
171 	 * The vis(3) functions, however, require single either bytes
172 	 * or a multibyte string as their arguments.  So we convert
173 	 * our input wchar_t and the following look-ahead wchar_t to
174 	 * a multibyte string for processing by vis(3).
175          */
176 
177 	/* Read one multibyte character, store as wchar_t */
178 	c = getwc(fp);
179 	if (c == WEOF && errno == EILSEQ) {
180 		/* Error in multibyte data.  Read one byte. */
181 		c = (wint_t)getc(fp);
182 		cerr = 1;
183 	}
184 	while (c != WEOF) {
185 		/* Clear multibyte input buffer. */
186 		memset(mbibuff, 0, sizeof(mbibuff));
187 		/* Read-ahead next multibyte character. */
188 		if (!cerr)
189 			rachar = getwc(fp);
190 		if (cerr || (rachar == WEOF && errno == EILSEQ)) {
191 			/* Error in multibyte data.  Read one byte. */
192 			rachar = (wint_t)getc(fp);
193 			raerr = 1;
194 		}
195 		if (none) {
196 			/* Handle -n flag. */
197 			cp = buff;
198 			*cp++ = c;
199 			if (c == '\\')
200 				*cp++ = '\\';
201 			*cp = '\0';
202 		} else if (markeol && c == '\n') {
203 			/* Handle -l flag. */
204 			cp = buff;
205 			if ((eflags & VIS_NOSLASH) == 0)
206 				*cp++ = '\\';
207 			*cp++ = '$';
208 			*cp++ = '\n';
209 			*cp = '\0';
210 		} else {
211 			/*
212 			 * Convert character using vis(3) library.
213 			 * At this point we will process one character.
214 			 * But we must pass the vis(3) library this
215 			 * character plus the next one because the next
216 			 * one is used as a look-ahead to decide how to
217 			 * encode this one under certain circumstances.
218 			 *
219 			 * Since our characters may be multibyte, e.g.,
220 			 * in the UTF-8 locale, we cannot use vis() and
221 			 * svis() which require byte input, so we must
222 			 * create a multibyte string and use strvisx().
223 			 */
224 			/* Treat EOF as a NUL char. */
225 			c1 = rachar;
226 			if (c1 == WEOF)
227 				c1 = L'\0';
228 			/*
229 			 * If we hit a multibyte conversion error above,
230 			 * insert byte directly into string buff because
231 			 * wctomb() will fail.  Else convert wchar_t to
232 			 * multibyte using wctomb().
233 			 */
234 			if (cerr) {
235 				*mbibuff = (char)c;
236 				mbilen = 1;
237 			} else
238 				mbilen = wctomb(mbibuff, c);
239 			/* Same for look-ahead character. */
240 			if (raerr)
241 				mbibuff[mbilen] = (char)c1;
242 			else
243 				wctomb(mbibuff + mbilen, c1);
244 			/* Perform encoding on just first character. */
245 			strsenvisx(buff, 4 * MB_LEN_MAX, mbibuff,
246 			    1, eflags, extra, &cerr);
247 		}
248 
249 		cp = buff;
250 		if (fold) {
251 #ifdef DEBUG
252 			if (debug)
253 				printf("<%02d,", col);
254 #endif
255 			col = foldit(cp, col, foldwidth, eflags);
256 #ifdef DEBUG
257 			if (debug)
258 				printf("%02d>", col);
259 #endif
260 		}
261 		do {
262 			putchar(*cp);
263 		} while (*++cp);
264 		c = rachar;
265 		cerr = raerr;
266 	}
267 	/*
268 	 * terminate partial line with a hidden newline
269 	 */
270 	if (fold && *(cp - 1) != '\n')
271 		printf(eflags & VIS_MIMESTYLE ? "=\n" : "\\\n");
272 }
273