xref: /freebsd/usr.bin/nl/nl.c (revision 02e9120893770924227138ba49df1edb3896112a)
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 typedef enum {
46 	number_all,		/* number all lines */
47 	number_nonempty,	/* number non-empty lines */
48 	number_none,		/* no line numbering */
49 	number_regex		/* number lines matching regular expression */
50 } numbering_type;
51 
52 struct numbering_property {
53 	const char * const	name;		/* for diagnostics */
54 	numbering_type		type;		/* numbering type */
55 	regex_t			expr;		/* for type == number_regex */
56 };
57 
58 /* line numbering formats */
59 #define FORMAT_LN	"%-*d"	/* left justified, leading zeros suppressed */
60 #define FORMAT_RN	"%*d"	/* right justified, leading zeros suppressed */
61 #define FORMAT_RZ	"%0*d"	/* right justified, leading zeros kept */
62 
63 #define FOOTER		0
64 #define BODY		1
65 #define HEADER		2
66 #define NP_LAST		HEADER
67 
68 static struct numbering_property numbering_properties[NP_LAST + 1] = {
69 	{ .name = "footer", .type = number_none },
70 	{ .name = "body", .type = number_nonempty },
71 	{ .name = "header", .type = number_none }
72 };
73 
74 #define max(a, b)	((a) > (b) ? (a) : (b))
75 
76 /*
77  * Maximum number of characters required for a decimal representation of a
78  * (signed) int; courtesy of tzcode.
79  */
80 #define INT_STRLEN_MAXIMUM \
81 	((sizeof (int) * CHAR_BIT - 1) * 302 / 1000 + 2)
82 
83 static void	filter(void);
84 static void	parse_numbering(const char *, int);
85 static void	usage(void);
86 
87 /*
88  * Dynamically allocated buffer suitable for string representation of ints.
89  */
90 static char *intbuffer;
91 
92 /* delimiter characters that indicate the start of a logical page section */
93 static char delim[2 * MB_LEN_MAX];
94 static int delimlen;
95 
96 /*
97  * Configurable parameters.
98  */
99 
100 /* line numbering format */
101 static const char *format = FORMAT_RN;
102 
103 /* increment value used to number logical page lines */
104 static int incr = 1;
105 
106 /* number of adjacent blank lines to be considered (and numbered) as one */
107 static unsigned int nblank = 1;
108 
109 /* whether to restart numbering at logical page delimiters */
110 static int restart = 1;
111 
112 /* characters used in separating the line number and the corrsp. text line */
113 static const char *sep = "\t";
114 
115 /* initial value used to number logical page lines */
116 static int startnum = 1;
117 
118 /* number of characters to be used for the line number */
119 /* should be unsigned but required signed by `*' precision conversion */
120 static int width = 6;
121 
122 
123 int
124 main(int argc, char *argv[])
125 {
126 	int c;
127 	long val;
128 	unsigned long uval;
129 	char *ep;
130 	size_t intbuffersize, clen;
131 	char delim1[MB_LEN_MAX] = { '\\' }, delim2[MB_LEN_MAX] = { ':' };
132 	size_t delim1len = 1, delim2len = 1;
133 
134 	(void)setlocale(LC_ALL, "");
135 
136 	while ((c = getopt(argc, argv, "pb:d:f:h:i:l:n:s:v:w:")) != -1) {
137 		switch (c) {
138 		case 'p':
139 			restart = 0;
140 			break;
141 		case 'b':
142 			parse_numbering(optarg, BODY);
143 			break;
144 		case 'd':
145 			clen = mbrlen(optarg, MB_CUR_MAX, NULL);
146 			if (clen == (size_t)-1 || clen == (size_t)-2)
147 				errc(EXIT_FAILURE, EILSEQ, NULL);
148 			if (clen != 0) {
149 				memcpy(delim1, optarg, delim1len = clen);
150 				clen = mbrlen(optarg + delim1len,
151 				    MB_CUR_MAX, NULL);
152 				if (clen == (size_t)-1 ||
153 				    clen == (size_t)-2)
154 					errc(EXIT_FAILURE, EILSEQ, NULL);
155 				if (clen != 0) {
156 					memcpy(delim2, optarg + delim1len,
157 					    delim2len = clen);
158 				if (optarg[delim1len + clen] != '\0')
159 					errx(EXIT_FAILURE,
160 					    "invalid delim argument -- %s",
161 					    optarg);
162 				}
163 			}
164 			break;
165 		case 'f':
166 			parse_numbering(optarg, FOOTER);
167 			break;
168 		case 'h':
169 			parse_numbering(optarg, HEADER);
170 			break;
171 		case 'i':
172 			errno = 0;
173 			val = strtol(optarg, &ep, 10);
174 			if ((ep != NULL && *ep != '\0') ||
175 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
176 				errx(EXIT_FAILURE,
177 				    "invalid incr argument -- %s", optarg);
178 			incr = (int)val;
179 			break;
180 		case 'l':
181 			errno = 0;
182 			uval = strtoul(optarg, &ep, 10);
183 			if ((ep != NULL && *ep != '\0') ||
184 			    (uval == ULONG_MAX && errno != 0))
185 				errx(EXIT_FAILURE,
186 				    "invalid num argument -- %s", optarg);
187 			nblank = (unsigned int)uval;
188 			break;
189 		case 'n':
190 			if (strcmp(optarg, "ln") == 0) {
191 				format = FORMAT_LN;
192 			} else if (strcmp(optarg, "rn") == 0) {
193 				format = FORMAT_RN;
194 			} else if (strcmp(optarg, "rz") == 0) {
195 				format = FORMAT_RZ;
196 			} else
197 				errx(EXIT_FAILURE,
198 				    "illegal format -- %s", optarg);
199 			break;
200 		case 's':
201 			sep = optarg;
202 			break;
203 		case 'v':
204 			errno = 0;
205 			val = strtol(optarg, &ep, 10);
206 			if ((ep != NULL && *ep != '\0') ||
207 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
208 				errx(EXIT_FAILURE,
209 				    "invalid startnum value -- %s", optarg);
210 			startnum = (int)val;
211 			break;
212 		case 'w':
213 			errno = 0;
214 			val = strtol(optarg, &ep, 10);
215 			if ((ep != NULL && *ep != '\0') ||
216 			 ((val == LONG_MIN || val == LONG_MAX) && errno != 0))
217 				errx(EXIT_FAILURE,
218 				    "invalid width value -- %s", optarg);
219 			width = (int)val;
220 			if (!(width > 0))
221 				errx(EXIT_FAILURE,
222 				    "width argument must be > 0 -- %d",
223 				    width);
224 			break;
225 		case '?':
226 		default:
227 			usage();
228 			/* NOTREACHED */
229 		}
230 	}
231 	argc -= optind;
232 	argv += optind;
233 
234 	switch (argc) {
235 	case 0:
236 		break;
237 	case 1:
238 		if (strcmp(argv[0], "-") != 0 &&
239 		    freopen(argv[0], "r", stdin) == NULL)
240 			err(EXIT_FAILURE, "%s", argv[0]);
241 		break;
242 	default:
243 		usage();
244 		/* NOTREACHED */
245 	}
246 
247 	/* Generate the delimiter sequence */
248 	memcpy(delim, delim1, delim1len);
249 	memcpy(delim + delim1len, delim2, delim2len);
250 	delimlen = delim1len + delim2len;
251 
252 	/* Allocate a buffer suitable for preformatting line number. */
253 	intbuffersize = max((int)INT_STRLEN_MAXIMUM, width) + 1; /* NUL */
254 	if ((intbuffer = malloc(intbuffersize)) == NULL)
255 		err(EXIT_FAILURE, "cannot allocate preformatting buffer");
256 
257 	/* Do the work. */
258 	filter();
259 
260 	exit(EXIT_SUCCESS);
261 	/* NOTREACHED */
262 }
263 
264 static void
265 filter(void)
266 {
267 	char *buffer;
268 	size_t buffersize;
269 	ssize_t linelen;
270 	int line;		/* logical line number */
271 	int section;		/* logical page section */
272 	unsigned int adjblank;	/* adjacent blank lines */
273 	int consumed;		/* intbuffer measurement */
274 	int donumber = 0, idx;
275 
276 	adjblank = 0;
277 	line = startnum;
278 	section = BODY;
279 
280 	buffer = NULL;
281 	buffersize = 0;
282 	while ((linelen = getline(&buffer, &buffersize, stdin)) > 0) {
283 		for (idx = FOOTER; idx <= NP_LAST; idx++) {
284 			/* Does it look like a delimiter? */
285 			if (delimlen * (idx + 1) > linelen)
286 				break;
287 			if (memcmp(buffer + delimlen * idx, delim,
288 			    delimlen) != 0)
289 				break;
290 			/* Was this the whole line? */
291 			if (buffer[delimlen * (idx + 1)] == '\n') {
292 				section = idx;
293 				adjblank = 0;
294 				if (restart)
295 					line = startnum;
296 				goto nextline;
297 			}
298 		}
299 
300 		switch (numbering_properties[section].type) {
301 		case number_all:
302 			/*
303 			 * Doing this for number_all only is disputable, but
304 			 * the standard expresses an explicit dependency on
305 			 * `-b a' etc.
306 			 */
307 			if (buffer[0] == '\n' && ++adjblank < nblank)
308 				donumber = 0;
309 			else
310 				donumber = 1, adjblank = 0;
311 			break;
312 		case number_nonempty:
313 			donumber = (buffer[0] != '\n');
314 			break;
315 		case number_none:
316 			donumber = 0;
317 			break;
318 		case number_regex:
319 			donumber =
320 			    (regexec(&numbering_properties[section].expr,
321 			    buffer, 0, NULL, 0) == 0);
322 			break;
323 		}
324 
325 		if (donumber) {
326 			/* Note: sprintf() is safe here. */
327 			consumed = sprintf(intbuffer, format, width, line);
328 			(void)printf("%s",
329 			    intbuffer + max(0, consumed - width));
330 			line += incr;
331 		} else {
332 			(void)printf("%*s", width, "");
333 		}
334 		(void)fputs(sep, stdout);
335 		(void)fwrite(buffer, linelen, 1, stdout);
336 
337 		if (ferror(stdout))
338 			err(EXIT_FAILURE, "output error");
339 nextline:
340 		;
341 	}
342 
343 	if (ferror(stdin))
344 		err(EXIT_FAILURE, "input error");
345 
346 	free(buffer);
347 }
348 
349 /*
350  * Various support functions.
351  */
352 
353 static void
354 parse_numbering(const char *argstr, int section)
355 {
356 	int error;
357 	char errorbuf[NL_TEXTMAX];
358 
359 	switch (argstr[0]) {
360 	case 'a':
361 		numbering_properties[section].type = number_all;
362 		break;
363 	case 'n':
364 		numbering_properties[section].type = number_none;
365 		break;
366 	case 't':
367 		numbering_properties[section].type = number_nonempty;
368 		break;
369 	case 'p':
370 		/* If there was a previous expression, throw it away. */
371 		if (numbering_properties[section].type == number_regex)
372 			regfree(&numbering_properties[section].expr);
373 		else
374 			numbering_properties[section].type = number_regex;
375 
376 		/* Compile/validate the supplied regular expression. */
377 		if ((error = regcomp(&numbering_properties[section].expr,
378 		    &argstr[1], REG_NEWLINE|REG_NOSUB)) != 0) {
379 			(void)regerror(error,
380 			    &numbering_properties[section].expr,
381 			    errorbuf, sizeof (errorbuf));
382 			errx(EXIT_FAILURE,
383 			    "%s expr: %s -- %s",
384 			    numbering_properties[section].name, errorbuf,
385 			    &argstr[1]);
386 		}
387 		break;
388 	default:
389 		errx(EXIT_FAILURE,
390 		    "illegal %s line numbering type -- %s",
391 		    numbering_properties[section].name, argstr);
392 	}
393 }
394 
395 static void
396 usage(void)
397 {
398 
399 	(void)fprintf(stderr,
400 "usage: nl [-p] [-b type] [-d delim] [-f type] [-h type] [-i incr] [-l num]\n"
401 "          [-n format] [-s sep] [-v startnum] [-w width] [file]\n");
402 	exit(EXIT_FAILURE);
403 }
404