xref: /freebsd/usr.bin/uniq/uniq.c (revision 6e660824a82f590542932de52f128db584029893)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Case Larsen.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1989, 1993\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)uniq.c	8.3 (Berkeley) 5/4/95";
42 #endif
43 static const char rcsid[] =
44   "$FreeBSD$";
45 #endif /* not lint */
46 
47 #include <sys/capability.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <limits.h>
53 #include <locale.h>
54 #include <nl_types.h>
55 #include <stdint.h>
56 #define _WITH_GETLINE
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <termios.h>
61 #include <unistd.h>
62 #include <wchar.h>
63 #include <wctype.h>
64 
65 static int cflag, dflag, uflag, iflag;
66 static int numchars, numfields, repeats;
67 
68 static FILE	*file(const char *, const char *);
69 static wchar_t	*convert(const char *);
70 static int	 inlcmp(const char *, const char *);
71 static void	 show(FILE *, const char *);
72 static wchar_t	*skip(wchar_t *);
73 static void	 obsolete(char *[]);
74 static void	 usage(void);
75 
76 static void
77 strerror_init(void)
78 {
79 
80 	/*
81 	 * Cache NLS data before entering capability mode.
82 	 * XXXPJD: There should be strerror_init() and strsignal_init() in libc.
83 	 */
84 	(void)catopen("libc", NL_CAT_LOCALE);
85 }
86 
87 int
88 main (int argc, char *argv[])
89 {
90 	wchar_t *tprev, *tthis;
91 	FILE *ifp, *ofp;
92 	int ch, comp;
93 	size_t prevbuflen, thisbuflen, b1;
94 	char *prevline, *thisline, *p;
95 	const char *ifn;
96 	cap_rights_t rights;
97 
98 	(void) setlocale(LC_ALL, "");
99 
100 	obsolete(argv);
101 	while ((ch = getopt(argc, argv, "cdif:s:u")) != -1)
102 		switch (ch) {
103 		case 'c':
104 			cflag = 1;
105 			break;
106 		case 'd':
107 			dflag = 1;
108 			break;
109 		case 'i':
110 			iflag = 1;
111 			break;
112 		case 'f':
113 			numfields = strtol(optarg, &p, 10);
114 			if (numfields < 0 || *p)
115 				errx(1, "illegal field skip value: %s", optarg);
116 			break;
117 		case 's':
118 			numchars = strtol(optarg, &p, 10);
119 			if (numchars < 0 || *p)
120 				errx(1, "illegal character skip value: %s", optarg);
121 			break;
122 		case 'u':
123 			uflag = 1;
124 			break;
125 		case '?':
126 		default:
127 			usage();
128 		}
129 
130 	argc -= optind;
131 	argv += optind;
132 
133 	/* If no flags are set, default is -d -u. */
134 	if (cflag) {
135 		if (dflag || uflag)
136 			usage();
137 	} else if (!dflag && !uflag)
138 		dflag = uflag = 1;
139 
140 	if (argc > 2)
141 		usage();
142 
143 	ifp = stdin;
144 	ifn = "stdin";
145 	ofp = stdout;
146 	if (argc > 0 && strcmp(argv[0], "-") != 0)
147 		ifp = file(ifn = argv[0], "r");
148 	if (cap_rights_limit(fileno(ifp), CAP_FSTAT | CAP_READ) < 0 &&
149 	    errno != ENOSYS) {
150 		err(1, "unable to limit rights for %s", ifn);
151 	}
152 	rights = CAP_FSTAT | CAP_WRITE;
153 	if (argc > 1)
154 		ofp = file(argv[1], "w");
155 	else
156 		rights |= CAP_IOCTL;
157 	if (cap_rights_limit(fileno(ofp), rights) < 0 && errno != ENOSYS) {
158 		err(1, "unable to limit rights for %s",
159 		    argc > 1 ? argv[1] : "stdout");
160 	}
161 	if ((rights & CAP_IOCTL) != 0) {
162 		unsigned long cmd;
163 
164 		cmd = TIOCGETA; /* required by isatty(3) in printf(3) */
165 
166 		if (cap_ioctls_limit(fileno(ofp), &cmd, 1) < 0 &&
167 		    errno != ENOSYS) {
168 			err(1, "unable to limit ioctls for %s",
169 			    argc > 1 ? argv[1] : "stdout");
170 		}
171 	}
172 
173 	strerror_init();
174 	if (cap_enter() < 0 && errno != ENOSYS)
175 		err(1, "unable to enter capability mode");
176 
177 	prevbuflen = thisbuflen = 0;
178 	prevline = thisline = NULL;
179 
180 	if (getline(&prevline, &prevbuflen, ifp) < 0) {
181 		if (ferror(ifp))
182 			err(1, "%s", ifn);
183 		exit(0);
184 	}
185 	tprev = convert(prevline);
186 
187 	if (!cflag && uflag && dflag)
188 		show(ofp, prevline);
189 
190 	tthis = NULL;
191 	while (getline(&thisline, &thisbuflen, ifp) >= 0) {
192 		if (tthis != NULL)
193 			free(tthis);
194 		tthis = convert(thisline);
195 
196 		if (tthis == NULL && tprev == NULL)
197 			comp = inlcmp(thisline, prevline);
198 		else if (tthis == NULL || tprev == NULL)
199 			comp = 1;
200 		else
201 			comp = wcscoll(tthis, tprev);
202 
203 		if (comp) {
204 			/* If different, print; set previous to new value. */
205 			if (cflag || !dflag || !uflag)
206 				show(ofp, prevline);
207 			p = prevline;
208 			b1 = prevbuflen;
209 			prevline = thisline;
210 			prevbuflen = thisbuflen;
211 			if (tprev != NULL)
212 				free(tprev);
213 			tprev = tthis;
214 			if (!cflag && uflag && dflag)
215 				show(ofp, prevline);
216 			thisline = p;
217 			thisbuflen = b1;
218 			tthis = NULL;
219 			repeats = 0;
220 		} else
221 			++repeats;
222 	}
223 	if (ferror(ifp))
224 		err(1, "%s", ifn);
225 	if (cflag || !dflag || !uflag)
226 		show(ofp, prevline);
227 	exit(0);
228 }
229 
230 static wchar_t *
231 convert(const char *str)
232 {
233 	size_t n;
234 	wchar_t *buf, *ret, *p;
235 
236 	if ((n = mbstowcs(NULL, str, 0)) == (size_t)-1)
237 		return (NULL);
238 	if (SIZE_MAX / sizeof(*buf) < n + 1)
239 		errx(1, "conversion buffer length overflow");
240 	if ((buf = malloc((n + 1) * sizeof(*buf))) == NULL)
241 		err(1, "malloc");
242 	if (mbstowcs(buf, str, n + 1) != n)
243 		errx(1, "internal mbstowcs() error");
244 	/* The last line may not end with \n. */
245 	if (n > 0 && buf[n - 1] == L'\n')
246 		buf[n - 1] = L'\0';
247 
248 	/* If requested get the chosen fields + character offsets. */
249 	if (numfields || numchars) {
250 		if ((ret = wcsdup(skip(buf))) == NULL)
251 			err(1, "wcsdup");
252 		free(buf);
253 	} else
254 		ret = buf;
255 
256 	if (iflag) {
257 		for (p = ret; *p != L'\0'; p++)
258 			*p = towlower(*p);
259 	}
260 
261 	return (ret);
262 }
263 
264 static int
265 inlcmp(const char *s1, const char *s2)
266 {
267 	int c1, c2;
268 
269 	while (*s1 == *s2++)
270 		if (*s1++ == '\0')
271 			return (0);
272 	c1 = (unsigned char)*s1;
273 	c2 = (unsigned char)*(s2 - 1);
274 	/* The last line may not end with \n. */
275 	if (c1 == '\n')
276 		c1 = '\0';
277 	if (c2 == '\n')
278 		c2 = '\0';
279 	return (c1 - c2);
280 }
281 
282 /*
283  * show --
284  *	Output a line depending on the flags and number of repetitions
285  *	of the line.
286  */
287 static void
288 show(FILE *ofp, const char *str)
289 {
290 
291 	if (cflag)
292 		(void)fprintf(ofp, "%4d %s", repeats + 1, str);
293 	if ((dflag && repeats) || (uflag && !repeats))
294 		(void)fprintf(ofp, "%s", str);
295 }
296 
297 static wchar_t *
298 skip(wchar_t *str)
299 {
300 	int nchars, nfields;
301 
302 	for (nfields = 0; *str != L'\0' && nfields++ != numfields; ) {
303 		while (iswblank(*str))
304 			str++;
305 		while (*str != L'\0' && !iswblank(*str))
306 			str++;
307 	}
308 	for (nchars = numchars; nchars-- && *str != L'\0'; ++str)
309 		;
310 	return(str);
311 }
312 
313 static FILE *
314 file(const char *name, const char *mode)
315 {
316 	FILE *fp;
317 
318 	if ((fp = fopen(name, mode)) == NULL)
319 		err(1, "%s", name);
320 	return(fp);
321 }
322 
323 static void
324 obsolete(char *argv[])
325 {
326 	int len;
327 	char *ap, *p, *start;
328 
329 	while ((ap = *++argv)) {
330 		/* Return if "--" or not an option of any form. */
331 		if (ap[0] != '-') {
332 			if (ap[0] != '+')
333 				return;
334 		} else if (ap[1] == '-')
335 			return;
336 		if (!isdigit((unsigned char)ap[1]))
337 			continue;
338 		/*
339 		 * Digit signifies an old-style option.  Malloc space for dash,
340 		 * new option and argument.
341 		 */
342 		len = strlen(ap);
343 		if ((start = p = malloc(len + 3)) == NULL)
344 			err(1, "malloc");
345 		*p++ = '-';
346 		*p++ = ap[0] == '+' ? 's' : 'f';
347 		(void)strcpy(p, ap + 1);
348 		*argv = start;
349 	}
350 }
351 
352 static void
353 usage(void)
354 {
355 	(void)fprintf(stderr,
356 "usage: uniq [-c | -d | -u] [-i] [-f fields] [-s chars] [input [output]]\n");
357 	exit(1);
358 }
359