xref: /openbsd/usr.bin/join/join.c (revision 73471bf0)
1 /* $OpenBSD: join.c,v 1.33 2020/07/23 20:13:01 martijn Exp $	*/
2 
3 /*-
4  * Copyright (c) 1991, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Steve Hayman of the Computer Science Department, Indiana University,
9  * Michiro Hikida and David Goodenough.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <err.h>
37 #include <errno.h>
38 #include <limits.h>
39 #include <locale.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 #include <wchar.h>
45 
46 /*
47  * There's a structure per input file which encapsulates the state of the
48  * file.  We repeatedly read lines from each file until we've read in all
49  * the consecutive lines from the file with a common join field.  Then we
50  * compare the set of lines with an equivalent set from the other file.
51  */
52 typedef struct {
53 	char *line;			/* line */
54 	size_t linealloc;		/* bytes allocated for line */
55 	char **fields;			/* line field(s) */
56 	u_long fieldcnt;		/* line field(s) count */
57 	u_long fieldalloc;		/* line field(s) allocated count */
58 } LINE;
59 
60 typedef struct {
61 	FILE *fp;			/* file descriptor */
62 	u_long joinf;			/* join field (-1, -2, -j) */
63 	int unpair;			/* output unpairable lines (-a) */
64 	u_long number;			/* 1 for file 1, 2 for file 2 */
65 	LINE *set;			/* set of lines with same field */
66 	int pushbool;			/* if pushback is set */
67 	u_long pushback;		/* line on the stack */
68 	u_long setcnt;			/* set count */
69 	u_long setalloc;		/* set allocated count */
70 } INPUT;
71 INPUT input1 = { NULL, 0, 0, 1, NULL, 0, 0, 0, 0 },
72       input2 = { NULL, 0, 0, 2, NULL, 0, 0, 0, 0 };
73 
74 typedef struct {
75 	u_long	filenum;	/* file number */
76 	u_long	fieldno;	/* field number */
77 } OLIST;
78 OLIST *olist;			/* output field list */
79 u_long olistcnt;		/* output field list count */
80 u_long olistalloc;		/* output field allocated count */
81 
82 int joinout = 1;		/* show lines with matched join fields (-v) */
83 int needsep;			/* need separator character */
84 int spans = 1;			/* span multiple delimiters (-t) */
85 char *empty;			/* empty field replacement string (-e) */
86 wchar_t tabchar[] = L" \t";	/* delimiter characters (-t) */
87 
88 int  cmp(LINE *, u_long, LINE *, u_long);
89 void fieldarg(char *);
90 void joinlines(INPUT *, INPUT *);
91 char *mbssep(char **, const wchar_t *);
92 void obsolete(char **);
93 void outfield(LINE *, u_long, int);
94 void outoneline(INPUT *, LINE *);
95 void outtwoline(INPUT *, LINE *, INPUT *, LINE *);
96 void slurp(INPUT *);
97 void usage(void);
98 
99 int
100 main(int argc, char *argv[])
101 {
102 	INPUT *F1, *F2;
103 	int aflag, ch, cval, vflag;
104 	char *end;
105 
106 	setlocale(LC_CTYPE, "");
107 
108 	if (pledge("stdio rpath", NULL) == -1)
109 		err(1, "pledge");
110 
111 	F1 = &input1;
112 	F2 = &input2;
113 
114 	aflag = vflag = 0;
115 	obsolete(argv);
116 	while ((ch = getopt(argc, argv, "\01a:e:j:1:2:o:t:v:")) != -1) {
117 		switch (ch) {
118 		case '\01':		/* See comment in obsolete(). */
119 			aflag = 1;
120 			F1->unpair = F2->unpair = 1;
121 			break;
122 		case '1':
123 			if ((F1->joinf = strtol(optarg, &end, 10)) < 1)
124 				errx(1, "-1 option field number less than 1");
125 			if (*end)
126 				errx(1, "illegal field number -- %s", optarg);
127 			--F1->joinf;
128 			break;
129 		case '2':
130 			if ((F2->joinf = strtol(optarg, &end, 10)) < 1)
131 				errx(1, "-2 option field number less than 1");
132 			if (*end)
133 				errx(1, "illegal field number -- %s", optarg);
134 			--F2->joinf;
135 			break;
136 		case 'a':
137 			aflag = 1;
138 			switch(strtol(optarg, &end, 10)) {
139 			case 1:
140 				F1->unpair = 1;
141 				break;
142 			case 2:
143 				F2->unpair = 1;
144 				break;
145 			default:
146 				errx(1, "-a option file number not 1 or 2");
147 				break;
148 			}
149 			if (*end)
150 				errx(1, "illegal file number -- %s", optarg);
151 			break;
152 		case 'e':
153 			empty = optarg;
154 			break;
155 		case 'j':
156 			if ((F1->joinf = F2->joinf = strtol(optarg, &end, 10)) < 1)
157 				errx(1, "-j option field number less than 1");
158 			if (*end)
159 				errx(1, "illegal field number -- %s", optarg);
160 			--F1->joinf;
161 			--F2->joinf;
162 			break;
163 		case 'o':
164 			fieldarg(optarg);
165 			break;
166 		case 't':
167 			spans = 0;
168 			if (mbtowc(tabchar, optarg, MB_CUR_MAX) !=
169 			    strlen(optarg))
170 				errx(1, "illegal tab character specification");
171 			tabchar[1] = L'\0';
172 			break;
173 		case 'v':
174 			vflag = 1;
175 			joinout = 0;
176 			switch (strtol(optarg, &end, 10)) {
177 			case 1:
178 				F1->unpair = 1;
179 				break;
180 			case 2:
181 				F2->unpair = 1;
182 				break;
183 			default:
184 				errx(1, "-v option file number not 1 or 2");
185 				break;
186 			}
187 			if (*end)
188 				errx(1, "illegal file number -- %s", optarg);
189 			break;
190 		case '?':
191 		default:
192 			usage();
193 		}
194 	}
195 	argc -= optind;
196 	argv += optind;
197 
198 	if (aflag && vflag)
199 		errx(1, "the -a and -v options are mutually exclusive");
200 
201 	if (argc != 2)
202 		usage();
203 
204 	/* Open the files; "-" means stdin. */
205 	if (!strcmp(*argv, "-"))
206 		F1->fp = stdin;
207 	else if ((F1->fp = fopen(*argv, "r")) == NULL)
208 		err(1, "%s", *argv);
209 	++argv;
210 	if (!strcmp(*argv, "-"))
211 		F2->fp = stdin;
212 	else if ((F2->fp = fopen(*argv, "r")) == NULL)
213 		err(1, "%s", *argv);
214 	if (F1->fp == stdin && F2->fp == stdin)
215 		errx(1, "only one input file may be stdin");
216 
217 	if (pledge("stdio", NULL) == -1)
218 		err(1, "pledge");
219 
220 	slurp(F1);
221 	slurp(F2);
222 
223 	/*
224 	 * We try to let the files have the same field value, advancing
225 	 * whoever falls behind and always advancing the file(s) we output
226 	 * from.
227 	*/
228 	while (F1->setcnt && F2->setcnt) {
229 		cval = cmp(F1->set, F1->joinf, F2->set, F2->joinf);
230 		if (cval == 0) {
231 			/* Oh joy, oh rapture, oh beauty divine! */
232 			if (joinout)
233 				joinlines(F1, F2);
234 			slurp(F1);
235 			slurp(F2);
236 		} else if (cval < 0) {
237 			/* File 1 takes the lead... */
238 			if (F1->unpair)
239 				joinlines(F1, NULL);
240 			slurp(F1);
241 		} else {
242 			/* File 2 takes the lead... */
243 			if (F2->unpair)
244 				joinlines(F2, NULL);
245 			slurp(F2);
246 		}
247 	}
248 
249 	/*
250 	 * Now that one of the files is used up, optionally output any
251 	 * remaining lines from the other file.
252 	 */
253 	if (F1->unpair)
254 		while (F1->setcnt) {
255 			joinlines(F1, NULL);
256 			slurp(F1);
257 		}
258 	if (F2->unpair)
259 		while (F2->setcnt) {
260 			joinlines(F2, NULL);
261 			slurp(F2);
262 		}
263 
264 	return 0;
265 }
266 
267 void
268 slurp(INPUT *F)
269 {
270 	LINE *lp, *lastlp, tmp;
271 	ssize_t len;
272 	u_long cnt;
273 	char *bp, *fieldp;
274 
275 	/*
276 	 * Read all of the lines from an input file that have the same
277 	 * join field.
278 	 */
279 
280 	F->setcnt = 0;
281 	for (lastlp = NULL; ; ++F->setcnt) {
282 		/*
283 		 * If we're out of space to hold line structures, allocate
284 		 * more.  Initialize the structure so that we know that this
285 		 * is new space.
286 		 */
287 		if (F->setcnt == F->setalloc) {
288 			LINE *p;
289 			u_long newsize = F->setalloc + 50;
290 			cnt = F->setalloc;
291 			if ((p = reallocarray(F->set, newsize, sizeof(LINE)))
292 			    == NULL)
293 				err(1, NULL);
294 			F->set = p;
295 			F->setalloc = newsize;
296 			memset(F->set + cnt, 0, 50 * sizeof(LINE));
297 			/* re-set lastlp in case it moved */
298 			if (lastlp != NULL)
299 				lastlp = &F->set[F->setcnt - 1];
300 		}
301 		/*
302 		 * Get any pushed back line, else get the next line.  Allocate
303 		 * space as necessary.  If taking the line from the stack swap
304 		 * the two structures so that we don't lose space allocated to
305 		 * either structure.  This could be avoided by doing another
306 		 * level of indirection, but it's probably okay as is.
307 		 */
308 		lp = &F->set[F->setcnt];
309 		if (F->setcnt)
310 			lastlp = &F->set[F->setcnt - 1];
311 		if (F->pushbool) {
312 			tmp = F->set[F->setcnt];
313 			F->set[F->setcnt] = F->set[F->pushback];
314 			F->set[F->pushback] = tmp;
315 			F->pushbool = 0;
316 			continue;
317 		}
318 		if ((len = getline(&(lp->line), &(lp->linealloc), F->fp)) == -1)
319 			break;
320 
321 		/* Remove the trailing newline, if any. */
322 		if (lp->line[len - 1] == '\n')
323 			lp->line[--len] = '\0';
324 
325 		/* Split the line into fields, allocate space as necessary. */
326 		lp->fieldcnt = 0;
327 		bp = lp->line;
328 		while ((fieldp = mbssep(&bp, tabchar)) != NULL) {
329 			if (spans && *fieldp == '\0')
330 				continue;
331 			if (lp->fieldcnt == lp->fieldalloc) {
332 				char **p;
333 				u_long newsize = lp->fieldalloc + 50;
334 				if ((p = reallocarray(lp->fields, newsize,
335 				    sizeof(char *))) == NULL)
336 					err(1, NULL);
337 				lp->fields = p;
338 				lp->fieldalloc = newsize;
339 			}
340 			lp->fields[lp->fieldcnt++] = fieldp;
341 		}
342 
343 		/* See if the join field value has changed. */
344 		if (lastlp != NULL && cmp(lp, F->joinf, lastlp, F->joinf)) {
345 			F->pushbool = 1;
346 			F->pushback = F->setcnt;
347 			break;
348 		}
349 	}
350 }
351 
352 char *
353 mbssep(char **stringp, const wchar_t *wcdelim)
354 {
355 	char *s, *p;
356 	size_t ndelim;
357 	int i;
358 	/* tabchar is never more than 2 */
359 	char mbdelim[2][MB_LEN_MAX + 1];
360 	size_t mblen[2];
361 
362 	if ((s = *stringp) == NULL)
363 		return NULL;
364 	ndelim = wcslen(wcdelim);
365 	for (i = 0; i < ndelim; i++) {
366 		/* wcdelim generated via mbtowc */
367 		mblen[i] = wctomb(mbdelim[i], wcdelim[i]);
368 	}
369 	for (p = s; *p != '\0'; p++) {
370 		for (i = 0; i < ndelim; i++) {
371 			if (strncmp(p, mbdelim[i], mblen[i]) == 0) {
372 				*p = '\0';
373 				*stringp = p + mblen[i];
374 				return s;
375 			}
376 		}
377 	}
378 	*stringp = NULL;
379 	return s;
380 }
381 
382 int
383 cmp(LINE *lp1, u_long fieldno1, LINE *lp2, u_long fieldno2)
384 {
385 	if (lp1->fieldcnt <= fieldno1)
386 		return lp2->fieldcnt <= fieldno2 ? 0 : -1;
387 	if (lp2->fieldcnt <= fieldno2)
388 		return 1;
389 	return strcmp(lp1->fields[fieldno1], lp2->fields[fieldno2]);
390 }
391 
392 void
393 joinlines(INPUT *F1, INPUT *F2)
394 {
395 	u_long cnt1, cnt2;
396 
397 	/*
398 	 * Output the results of a join comparison.  The output may be from
399 	 * either file 1 or file 2 (in which case the first argument is the
400 	 * file from which to output) or from both.
401 	 */
402 	if (F2 == NULL) {
403 		for (cnt1 = 0; cnt1 < F1->setcnt; ++cnt1)
404 			outoneline(F1, &F1->set[cnt1]);
405 		return;
406 	}
407 	for (cnt1 = 0; cnt1 < F1->setcnt; ++cnt1)
408 		for (cnt2 = 0; cnt2 < F2->setcnt; ++cnt2)
409 			outtwoline(F1, &F1->set[cnt1], F2, &F2->set[cnt2]);
410 }
411 
412 void
413 outoneline(INPUT *F, LINE *lp)
414 {
415 	u_long cnt;
416 
417 	/*
418 	 * Output a single line from one of the files, according to the
419 	 * join rules.  This happens when we are writing unmatched single
420 	 * lines.  Output empty fields in the right places.
421 	 */
422 	if (olist)
423 		for (cnt = 0; cnt < olistcnt; ++cnt) {
424 			if (olist[cnt].filenum == F->number)
425 				outfield(lp, olist[cnt].fieldno, 0);
426 			else if (olist[cnt].filenum == 0)
427 				outfield(lp, F->joinf, 0);
428 			else
429 				outfield(lp, 0, 1);
430 		}
431 	else {
432 		/*
433 		 * Output the join field, then the remaining fields from F
434 		 */
435 		outfield(lp, F->joinf, 0);
436 		for (cnt = 0; cnt < lp->fieldcnt; ++cnt)
437 			if (F->joinf != cnt)
438 				outfield(lp, cnt, 0);
439 	}
440 
441 	putchar('\n');
442 	if (ferror(stdout))
443 		err(1, "stdout");
444 	needsep = 0;
445 }
446 
447 void
448 outtwoline(INPUT *F1, LINE *lp1, INPUT *F2, LINE *lp2)
449 {
450 	u_long cnt;
451 
452 	/* Output a pair of lines according to the join list (if any). */
453 	if (olist) {
454 		for (cnt = 0; cnt < olistcnt; ++cnt)
455 			if (olist[cnt].filenum == 0) {
456 				if (lp1->fieldcnt >= F1->joinf)
457 					outfield(lp1, F1->joinf, 0);
458 				else
459 					outfield(lp2, F2->joinf, 0);
460 			} else if (olist[cnt].filenum == 1)
461 				outfield(lp1, olist[cnt].fieldno, 0);
462 			else /* if (olist[cnt].filenum == 2) */
463 				outfield(lp2, olist[cnt].fieldno, 0);
464 	} else {
465 		/*
466 		 * Output the join field, then the remaining fields from F1
467 		 * and F2.
468 		 */
469 		outfield(lp1, F1->joinf, 0);
470 		for (cnt = 0; cnt < lp1->fieldcnt; ++cnt)
471 			if (F1->joinf != cnt)
472 				outfield(lp1, cnt, 0);
473 		for (cnt = 0; cnt < lp2->fieldcnt; ++cnt)
474 			if (F2->joinf != cnt)
475 				outfield(lp2, cnt, 0);
476 	}
477 	putchar('\n');
478 	if (ferror(stdout))
479 		err(1, "stdout");
480 	needsep = 0;
481 }
482 
483 void
484 outfield(LINE *lp, u_long fieldno, int out_empty)
485 {
486 	if (needsep++)
487 		putwchar(*tabchar);
488 	if (!ferror(stdout)) {
489 		if (lp->fieldcnt <= fieldno || out_empty) {
490 			if (empty != NULL)
491 				fputs(empty, stdout);
492 		} else {
493 			if (*lp->fields[fieldno] == '\0')
494 				return;
495 			fputs(lp->fields[fieldno], stdout);
496 		}
497 	}
498 	if (ferror(stdout))
499 		err(1, "stdout");
500 }
501 
502 /*
503  * Convert an output list argument "2.1, 1.3, 2.4" into an array of output
504  * fields.
505  */
506 void
507 fieldarg(char *option)
508 {
509 	u_long fieldno, filenum;
510 	char *end, *token;
511 
512 	while ((token = strsep(&option, ", \t")) != NULL) {
513 		if (*token == '\0')
514 			continue;
515 		if (token[0] == '0')
516 			filenum = fieldno = 0;
517 		else if ((token[0] == '1' || token[0] == '2') &&
518 		    token[1] == '.') {
519 			filenum = token[0] - '0';
520 			fieldno = strtol(token + 2, &end, 10);
521 			if (*end)
522 				errx(1, "malformed -o option field");
523 			if (fieldno == 0)
524 				errx(1, "field numbers are 1 based");
525 			--fieldno;
526 		} else
527 			errx(1, "malformed -o option field");
528 		if (olistcnt == olistalloc) {
529 			OLIST *p;
530 			u_long newsize = olistalloc + 50;
531 			if ((p = reallocarray(olist, newsize, sizeof(OLIST)))
532 			    == NULL)
533 				err(1, NULL);
534 			olist = p;
535 			olistalloc = newsize;
536 		}
537 		olist[olistcnt].filenum = filenum;
538 		olist[olistcnt].fieldno = fieldno;
539 		++olistcnt;
540 	}
541 }
542 
543 void
544 obsolete(char **argv)
545 {
546 	size_t len;
547 	char **p, *ap, *t;
548 
549 	while ((ap = *++argv) != NULL) {
550 		/* Return if "--". */
551 		if (ap[0] == '-' && ap[1] == '-')
552 			return;
553 		/* skip if not an option */
554 		if (ap[0] != '-')
555 			continue;
556 		switch (ap[1]) {
557 		case 'a':
558 			/*
559 			 * The original join allowed "-a", which meant the
560 			 * same as -a1 plus -a2.  POSIX 1003.2, Draft 11.2
561 			 * only specifies this as "-a 1" and "a -2", so we
562 			 * have to use another option flag, one that is
563 			 * unlikely to ever be used or accidentally entered
564 			 * on the command line.  (Well, we could reallocate
565 			 * the argv array, but that hardly seems worthwhile.)
566 			 */
567 			if (ap[2] == '\0' && (argv[1] == NULL ||
568 			    (strcmp(argv[1], "1") != 0 &&
569 			    strcmp(argv[1], "2") != 0))) {
570 				ap[1] = '\01';
571 				warnx("-a option used without an argument; "
572 				    "reverting to historical behavior");
573 			}
574 			break;
575 		case 'j':
576 			/*
577 			 * The original join allowed "-j[12] arg" and "-j arg".
578 			 * Convert the former to "-[12] arg".  Don't convert
579 			 * the latter since getopt(3) can handle it.
580 			 */
581 			switch(ap[2]) {
582 			case '1':
583 			case '2':
584 				if (ap[3] != '\0')
585 					goto jbad;
586 				ap[1] = ap[2];
587 				ap[2] = '\0';
588 				break;
589 			case '\0':
590 				break;
591 			default:
592 jbad:				warnx("unknown option -- %s", ap + 1);
593 				usage();
594 			}
595 			break;
596 		case 'o':
597 			/*
598 			 * The original join allowed "-o arg arg".
599 			 * Convert to "-o arg -o arg".
600 			 */
601 			if (ap[2] != '\0' || argv[1] == NULL)
602 				break;
603 			for (p = argv + 2; *p != NULL; ++p) {
604 				if (p[0][0] == '0' || ((p[0][0] != '1' &&
605 				    p[0][0] != '2') || p[0][1] != '.'))
606 					break;
607 				len = strlen(*p);
608 				if (len - 2 != strspn(*p + 2, "0123456789"))
609 					break;
610 				if ((t = malloc(len + 3)) == NULL)
611 					err(1, NULL);
612 				t[0] = '-';
613 				t[1] = 'o';
614 				memmove(t + 2, *p, len + 1);
615 				*p = t;
616 			}
617 			argv = p - 1;
618 			break;
619 		}
620 	}
621 }
622 
623 void
624 usage(void)
625 {
626 	int len;
627 	extern char *__progname;
628 
629 	len = strlen(__progname) + sizeof("usage: ");
630 	(void)fprintf(stderr, "usage: %s [-1 field] [-2 field] "
631 	    "[-a file_number | -v file_number] [-e string]\n"
632 	    "%*s[-o list] [-t char] file1 file2\n",
633 	    __progname, len, "");
634 	exit(1);
635 }
636