xref: /freebsd/usr.bin/nl/nl.c (revision dfd52321b7beba716fa2bdd4f54e57e9ac806e96)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Klaus Klein.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/types.h>
33 
34 #include <err.h>
35 #include <errno.h>
36 #include <limits.h>
37 #include <locale.h>
38 #include <regex.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 #include <wchar.h>
44 
45 #include <capsicum_helpers.h>
46 
47 typedef enum {
48 	number_all,		/* number all lines */
49 	number_nonempty,	/* number non-empty lines */
50 	number_none,		/* no line numbering */
51 	number_regex		/* number lines matching regular expression */
52 } numbering_type;
53 
54 struct numbering_property {
55 	const char * const	name;		/* for diagnostics */
56 	numbering_type		type;		/* numbering type */
57 	regex_t			expr;		/* for type == number_regex */
58 };
59 
60 /* line numbering formats */
61 #define FORMAT_LN	"%-*d"	/* left justified, leading zeros suppressed */
62 #define FORMAT_RN	"%*d"	/* right justified, leading zeros suppressed */
63 #define FORMAT_RZ	"%0*d"	/* right justified, leading zeros kept */
64 
65 #define FOOTER		0
66 #define BODY		1
67 #define HEADER		2
68 #define NP_LAST		HEADER
69 
70 static struct numbering_property numbering_properties[NP_LAST + 1] = {
71 	{ .name = "footer", .type = number_none },
72 	{ .name = "body", .type = number_nonempty },
73 	{ .name = "header", .type = number_none }
74 };
75 
76 #define max(a, b)	((a) > (b) ? (a) : (b))
77 
78 /*
79  * Maximum number of characters required for a decimal representation of a
80  * (signed) int; courtesy of tzcode.
81  */
82 #define INT_STRLEN_MAXIMUM \
83 	((sizeof (int) * CHAR_BIT - 1) * 302 / 1000 + 2)
84 
85 static void	filter(void);
86 static void	parse_numbering(const char *, int);
87 static void	usage(void);
88 
89 /*
90  * Dynamically allocated buffer suitable for string representation of ints.
91  */
92 static char *intbuffer;
93 
94 /* delimiter characters that indicate the start of a logical page section */
95 static char delim[2 * MB_LEN_MAX];
96 static int delimlen;
97 
98 /*
99  * Configurable parameters.
100  */
101 
102 /* line numbering format */
103 static const char *format = FORMAT_RN;
104 
105 /* increment value used to number logical page lines */
106 static int incr = 1;
107 
108 /* number of adjacent blank lines to be considered (and numbered) as one */
109 static unsigned int nblank = 1;
110 
111 /* whether to restart numbering at logical page delimiters */
112 static int restart = 1;
113 
114 /* characters used in separating the line number and the corrsp. text line */
115 static const char *sep = "\t";
116 
117 /* initial value used to number logical page lines */
118 static int startnum = 1;
119 
120 /* number of characters to be used for the line number */
121 /* should be unsigned but required signed by `*' precision conversion */
122 static int width = 6;
123 
124 
125 int
main(int argc,char * argv[])126 main(int argc, char *argv[])
127 {
128 	int c;
129 	long val;
130 	unsigned long uval;
131 	char *ep;
132 	size_t intbuffersize, clen;
133 	char delim1[MB_LEN_MAX] = { '\\' }, delim2[MB_LEN_MAX] = { ':' };
134 	size_t delim1len = 1, delim2len = 1;
135 
136 	(void)setlocale(LC_ALL, "");
137 
138 	while ((c = getopt(argc, argv, "pb:d:f:h:i:l:n:s:v:w:")) != -1) {
139 		switch (c) {
140 		case 'p':
141 			restart = 0;
142 			break;
143 		case 'b':
144 			parse_numbering(optarg, BODY);
145 			break;
146 		case 'd':
147 			clen = mbrlen(optarg, MB_CUR_MAX, NULL);
148 			if (clen == (size_t)-1 || clen == (size_t)-2)
149 				errc(EXIT_FAILURE, EILSEQ, NULL);
150 			if (clen != 0) {
151 				memcpy(delim1, optarg, delim1len = clen);
152 				clen = mbrlen(optarg + delim1len,
153 				    MB_CUR_MAX, NULL);
154 				if (clen == (size_t)-1 ||
155 				    clen == (size_t)-2)
156 					errc(EXIT_FAILURE, EILSEQ, NULL);
157 				if (clen != 0) {
158 					memcpy(delim2, optarg + delim1len,
159 					    delim2len = clen);
160 				if (optarg[delim1len + clen] != '\0')
161 					errx(EXIT_FAILURE,
162 					    "invalid delim argument -- %s",
163 					    optarg);
164 				}
165 			}
166 			break;
167 		case 'f':
168 			parse_numbering(optarg, FOOTER);
169 			break;
170 		case 'h':
171 			parse_numbering(optarg, HEADER);
172 			break;
173 		case 'i':
174 			errno = 0;
175 			val = strtol(optarg, &ep, 10);
176 			if ((ep != NULL && *ep != '\0') ||
177 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
178 				errx(EXIT_FAILURE,
179 				    "invalid incr argument -- %s", optarg);
180 			incr = (int)val;
181 			break;
182 		case 'l':
183 			errno = 0;
184 			uval = strtoul(optarg, &ep, 10);
185 			if ((ep != NULL && *ep != '\0') ||
186 			    (uval == ULONG_MAX && errno != 0))
187 				errx(EXIT_FAILURE,
188 				    "invalid num argument -- %s", optarg);
189 			nblank = (unsigned int)uval;
190 			break;
191 		case 'n':
192 			if (strcmp(optarg, "ln") == 0) {
193 				format = FORMAT_LN;
194 			} else if (strcmp(optarg, "rn") == 0) {
195 				format = FORMAT_RN;
196 			} else if (strcmp(optarg, "rz") == 0) {
197 				format = FORMAT_RZ;
198 			} else
199 				errx(EXIT_FAILURE,
200 				    "illegal format -- %s", optarg);
201 			break;
202 		case 's':
203 			sep = optarg;
204 			break;
205 		case 'v':
206 			errno = 0;
207 			val = strtol(optarg, &ep, 10);
208 			if ((ep != NULL && *ep != '\0') ||
209 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
210 				errx(EXIT_FAILURE,
211 				    "invalid startnum value -- %s", optarg);
212 			startnum = (int)val;
213 			break;
214 		case 'w':
215 			errno = 0;
216 			val = strtol(optarg, &ep, 10);
217 			if ((ep != NULL && *ep != '\0') ||
218 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
219 				errx(EXIT_FAILURE,
220 				    "invalid width value -- %s", optarg);
221 			width = (int)val;
222 			if (!(width > 0))
223 				errx(EXIT_FAILURE,
224 				    "width argument must be > 0 -- %d",
225 				    width);
226 			break;
227 		case '?':
228 		default:
229 			usage();
230 			/* NOTREACHED */
231 		}
232 	}
233 	argc -= optind;
234 	argv += optind;
235 
236 	switch (argc) {
237 	case 0:
238 		break;
239 	case 1:
240 		if (strcmp(argv[0], "-") != 0 &&
241 		    freopen(argv[0], "r", stdin) == NULL)
242 			err(EXIT_FAILURE, "%s", argv[0]);
243 		break;
244 	default:
245 		usage();
246 		/* NOTREACHED */
247 	}
248 
249 	/* Limit standard descriptors and enter capability mode */
250 	caph_cache_catpages();
251 	if (caph_limit_stdio() < 0 || caph_enter() < 0)
252 		err(EXIT_FAILURE, "capsicum");
253 
254 	/* Generate the delimiter sequence */
255 	memcpy(delim, delim1, delim1len);
256 	memcpy(delim + delim1len, delim2, delim2len);
257 	delimlen = delim1len + delim2len;
258 
259 	/* Allocate a buffer suitable for preformatting line number. */
260 	intbuffersize = max((int)INT_STRLEN_MAXIMUM, width) + 1; /* NUL */
261 	if ((intbuffer = malloc(intbuffersize)) == NULL)
262 		err(EXIT_FAILURE, "cannot allocate preformatting buffer");
263 
264 	/* Do the work. */
265 	filter();
266 
267 	exit(EXIT_SUCCESS);
268 	/* NOTREACHED */
269 }
270 
271 static void
filter(void)272 filter(void)
273 {
274 	char *buffer;
275 	size_t buffersize;
276 	ssize_t linelen;
277 	int line;		/* logical line number */
278 	int section;		/* logical page section */
279 	unsigned int adjblank;	/* adjacent blank lines */
280 	int consumed;		/* intbuffer measurement */
281 	int donumber = 0, idx;
282 
283 	adjblank = 0;
284 	line = startnum;
285 	section = BODY;
286 
287 	buffer = NULL;
288 	buffersize = 0;
289 	while ((linelen = getline(&buffer, &buffersize, stdin)) > 0) {
290 		for (idx = FOOTER; idx <= NP_LAST; idx++) {
291 			/* Does it look like a delimiter? */
292 			if (delimlen * (idx + 1) > linelen)
293 				break;
294 			if (memcmp(buffer + delimlen * idx, delim,
295 			    delimlen) != 0)
296 				break;
297 			/* Was this the whole line? */
298 			if (buffer[delimlen * (idx + 1)] == '\n') {
299 				section = idx;
300 				adjblank = 0;
301 				if (restart)
302 					line = startnum;
303 				goto nextline;
304 			}
305 		}
306 
307 		switch (numbering_properties[section].type) {
308 		case number_all:
309 			/*
310 			 * Doing this for number_all only is disputable, but
311 			 * the standard expresses an explicit dependency on
312 			 * `-b a' etc.
313 			 */
314 			if (buffer[0] == '\n' && ++adjblank < nblank)
315 				donumber = 0;
316 			else
317 				donumber = 1, adjblank = 0;
318 			break;
319 		case number_nonempty:
320 			donumber = (buffer[0] != '\n');
321 			break;
322 		case number_none:
323 			donumber = 0;
324 			break;
325 		case number_regex:
326 			donumber =
327 			    (regexec(&numbering_properties[section].expr,
328 			    buffer, 0, NULL, 0) == 0);
329 			break;
330 		}
331 
332 		if (donumber) {
333 			/* Note: sprintf() is safe here. */
334 			consumed = sprintf(intbuffer, format, width, line);
335 			(void)printf("%s",
336 			    intbuffer + max(0, consumed - width));
337 			line += incr;
338 		} else {
339 			(void)printf("%*s", width, "");
340 		}
341 		(void)fputs(sep, stdout);
342 		(void)fwrite(buffer, linelen, 1, stdout);
343 
344 		if (ferror(stdout))
345 			err(EXIT_FAILURE, "output error");
346 nextline:
347 		;
348 	}
349 
350 	if (ferror(stdin))
351 		err(EXIT_FAILURE, "input error");
352 
353 	free(buffer);
354 }
355 
356 /*
357  * Various support functions.
358  */
359 
360 static void
parse_numbering(const char * argstr,int section)361 parse_numbering(const char *argstr, int section)
362 {
363 	int error;
364 	char errorbuf[NL_TEXTMAX];
365 
366 	switch (argstr[0]) {
367 	case 'a':
368 		numbering_properties[section].type = number_all;
369 		break;
370 	case 'n':
371 		numbering_properties[section].type = number_none;
372 		break;
373 	case 't':
374 		numbering_properties[section].type = number_nonempty;
375 		break;
376 	case 'p':
377 		/* If there was a previous expression, throw it away. */
378 		if (numbering_properties[section].type == number_regex)
379 			regfree(&numbering_properties[section].expr);
380 		else
381 			numbering_properties[section].type = number_regex;
382 
383 		/* Compile/validate the supplied regular expression. */
384 		if ((error = regcomp(&numbering_properties[section].expr,
385 		    &argstr[1], REG_NEWLINE|REG_NOSUB)) != 0) {
386 			(void)regerror(error,
387 			    &numbering_properties[section].expr,
388 			    errorbuf, sizeof (errorbuf));
389 			errx(EXIT_FAILURE,
390 			    "%s expr: %s -- %s",
391 			    numbering_properties[section].name, errorbuf,
392 			    &argstr[1]);
393 		}
394 		break;
395 	default:
396 		errx(EXIT_FAILURE,
397 		    "illegal %s line numbering type -- %s",
398 		    numbering_properties[section].name, argstr);
399 	}
400 }
401 
402 static void
usage(void)403 usage(void)
404 {
405 
406 	(void)fprintf(stderr,
407 "usage: nl [-p] [-b type] [-d delim] [-f type] [-h type] [-i incr] [-l num]\n"
408 "          [-n format] [-s sep] [-v startnum] [-w width] [file]\n");
409 	exit(EXIT_FAILURE);
410 }
411