xref: /openbsd-src/usr.bin/patch/patch.c (revision 9f11a5cfec7d60b9e193f526c84b9e125528f6fc)
1 /*	$OpenBSD: patch.c,v 1.39 2004/06/14 18:26:33 otto Exp $	*/
2 
3 /*
4  * patch - a program to apply diffs to original files
5  *
6  * Copyright 1986, Larry Wall
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following condition is met:
10  * 1. Redistributions of source code must retain the above copyright notice,
11  * this condition and the following disclaimer.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
17  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
19  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
20  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
26  * behaviour
27  */
28 
29 #ifndef lint
30 static const char rcsid[] = "$OpenBSD: patch.c,v 1.39 2004/06/14 18:26:33 otto Exp $";
31 #endif /* not lint */
32 
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <unistd.h>
36 
37 #include <ctype.h>
38 #include <getopt.h>
39 #include <limits.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <stdlib.h>
43 
44 #include "common.h"
45 #include "util.h"
46 #include "pch.h"
47 #include "inp.h"
48 #include "backupfile.h"
49 #include "pathnames.h"
50 
51 int		filemode = 0644;
52 
53 char		buf[MAXLINELEN];	/* general purpose buffer */
54 
55 bool		using_plan_a = true;	/* try to keep everything in memory */
56 bool		out_of_mem = false;	/* ran out of memory in plan a */
57 
58 #define MAXFILEC 2
59 
60 char		*filearg[MAXFILEC];
61 bool		ok_to_create_file = false;
62 char		*outname = NULL;
63 char		*origprae = NULL;
64 char		*TMPOUTNAME;
65 char		*TMPINNAME;
66 char		*TMPREJNAME;
67 char		*TMPPATNAME;
68 bool		toutkeep = false;
69 bool		trejkeep = false;
70 bool		warn_on_invalid_line;
71 bool		last_line_missing_eol;
72 
73 #ifdef DEBUGGING
74 int		debug = 0;
75 #endif
76 
77 bool		force = false;
78 bool		batch = false;
79 bool		verbose = true;
80 bool		reverse = false;
81 bool		noreverse = false;
82 bool		skip_rest_of_patch = false;
83 int		strippath = 957;
84 bool		canonicalize = false;
85 bool		check_only = false;
86 int		diff_type = 0;
87 char		*revision = NULL;	/* prerequisite revision, if any */
88 LINENUM		input_lines = 0;	/* how long is input file in lines */
89 int		posix = 0;		/* strict POSIX mode? */
90 
91 static void	reinitialize_almost_everything(void);
92 static void	get_some_switches(void);
93 static LINENUM	locate_hunk(LINENUM);
94 static void	abort_hunk(void);
95 static void	apply_hunk(LINENUM);
96 static void	init_output(const char *);
97 static void	init_reject(const char *);
98 static void	copy_till(LINENUM, bool);
99 static void	spew_output(void);
100 static void	dump_line(LINENUM, bool);
101 static bool	patch_match(LINENUM, LINENUM, LINENUM);
102 static bool	similar(const char *, const char *, int);
103 static __dead void usage(void);
104 
105 /* true if -E was specified on command line.  */
106 static bool	remove_empty_files = false;
107 
108 /* true if -R was specified on command line.  */
109 static bool	reverse_flag_specified = false;
110 
111 /* buffer holding the name of the rejected patch file. */
112 static char	rejname[NAME_MAX + 1];
113 
114 /* buffer for stderr */
115 static char	serrbuf[BUFSIZ];
116 
117 /* how many input lines have been irretractibly output */
118 static LINENUM	last_frozen_line = 0;
119 
120 static int	Argc;		/* guess */
121 static char	**Argv;
122 static int	Argc_last;	/* for restarting plan_b */
123 static char	**Argv_last;
124 
125 static FILE	*ofp = NULL;	/* output file pointer */
126 static FILE	*rejfp = NULL;	/* reject file pointer */
127 
128 static int	filec = 0;	/* how many file arguments? */
129 static LINENUM	last_offset = 0;
130 static LINENUM	maxfuzz = 2;
131 
132 /* patch using ifdef, ifndef, etc. */
133 static bool		do_defines = false;
134 /* #ifdef xyzzy */
135 static char		if_defined[128];
136 /* #ifndef xyzzy */
137 static char		not_defined[128];
138 /* #else */
139 static const char	else_defined[] = "#else\n";
140 /* #endif xyzzy */
141 static char		end_defined[128];
142 
143 
144 /* Apply a set of diffs as appropriate. */
145 
146 int
147 main(int argc, char *argv[])
148 {
149 	int	error = 0, hunk, failed, patch_seen = 0, i, fd;
150 	LINENUM	where = 0, newwhere, fuzz, mymaxfuzz;
151 	const	char *tmpdir;
152 	char	*v;
153 
154 	setbuf(stderr, serrbuf);
155 	for (i = 0; i < MAXFILEC; i++)
156 		filearg[i] = NULL;
157 
158 	/* Cons up the names of the temporary files.  */
159 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
160 		tmpdir = _PATH_TMP;
161 	for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
162 		;
163 	i++;
164 	if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
165 		fatal("cannot allocate memory");
166 	if ((fd = mkstemp(TMPOUTNAME)) < 0)
167 		pfatal("can't create %s", TMPOUTNAME);
168 	close(fd);
169 
170 	if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
171 		fatal("cannot allocate memory");
172 	if ((fd = mkstemp(TMPINNAME)) < 0)
173 		pfatal("can't create %s", TMPINNAME);
174 	close(fd);
175 
176 	if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
177 		fatal("cannot allocate memory");
178 	if ((fd = mkstemp(TMPREJNAME)) < 0)
179 		pfatal("can't create %s", TMPREJNAME);
180 	close(fd);
181 
182 	if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
183 		fatal("cannot allocate memory");
184 	if ((fd = mkstemp(TMPPATNAME)) < 0)
185 		pfatal("can't create %s", TMPPATNAME);
186 	close(fd);
187 
188 	v = getenv("SIMPLE_BACKUP_SUFFIX");
189 	if (v)
190 		simple_backup_suffix = v;
191 	else
192 		simple_backup_suffix = ORIGEXT;
193 
194 	/* parse switches */
195 	Argc = argc;
196 	Argv = argv;
197 	get_some_switches();
198 
199 	if (backup_type == none) {
200 		if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
201 			v = getenv("VERSION_CONTROL");
202 		if (v != NULL || !posix)
203 			backup_type = get_version(v);	/* OK to pass NULL. */
204 	}
205 
206 	/* make sure we clean up /tmp in case of disaster */
207 	set_signals(0);
208 
209 	for (open_patch_file(filearg[1]); there_is_another_patch();
210 	    reinitialize_almost_everything()) {
211 		/* for each patch in patch file */
212 
213 		patch_seen = true;
214 		warn_on_invalid_line = true;
215 
216 		if (outname == NULL)
217 			outname = savestr(filearg[0]);
218 
219 		/* for ed script just up and do it and exit */
220 		if (diff_type == ED_DIFF) {
221 			do_ed_script();
222 			continue;
223 		}
224 		/* initialize the patched file */
225 		if (!skip_rest_of_patch)
226 			init_output(TMPOUTNAME);
227 
228 		/* initialize reject file */
229 		init_reject(TMPREJNAME);
230 
231 		/* find out where all the lines are */
232 		if (!skip_rest_of_patch)
233 			scan_input(filearg[0]);
234 
235 		/* from here on, open no standard i/o files, because malloc */
236 		/* might misfire and we can't catch it easily */
237 
238 		/* apply each hunk of patch */
239 		hunk = 0;
240 		failed = 0;
241 		out_of_mem = false;
242 		while (another_hunk()) {
243 			hunk++;
244 			fuzz = 0;
245 			mymaxfuzz = pch_context();
246 			if (maxfuzz < mymaxfuzz)
247 				mymaxfuzz = maxfuzz;
248 			if (!skip_rest_of_patch) {
249 				do {
250 					where = locate_hunk(fuzz);
251 					if (hunk == 1 && where == 0 && !force) {
252 						/* dwim for reversed patch? */
253 						if (!pch_swap()) {
254 							if (fuzz == 0)
255 								say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
256 							continue;
257 						}
258 						reverse = !reverse;
259 						/* try again */
260 						where = locate_hunk(fuzz);
261 						if (where == 0) {
262 							/* didn't find it swapped */
263 							if (!pch_swap())
264 								/* put it back to normal */
265 								fatal("lost hunk on alloc error!\n");
266 							reverse = !reverse;
267 						} else if (noreverse) {
268 							if (!pch_swap())
269 								/* put it back to normal */
270 								fatal("lost hunk on alloc error!\n");
271 							reverse = !reverse;
272 							say("Ignoring previously applied (or reversed) patch.\n");
273 							skip_rest_of_patch = true;
274 						} else if (batch) {
275 							if (verbose)
276 								say("%seversed (or previously applied) patch detected!  %s -R.",
277 								    reverse ? "R" : "Unr",
278 								    reverse ? "Assuming" : "Ignoring");
279 						} else {
280 							ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
281 							    reverse ? "R" : "Unr",
282 							    reverse ? "Assume" : "Ignore");
283 							if (*buf == 'n') {
284 								ask("Apply anyway? [n] ");
285 								if (*buf != 'y')
286 									skip_rest_of_patch = true;
287 								where = 0;
288 								reverse = !reverse;
289 								if (!pch_swap())
290 									/* put it back to normal */
291 									fatal("lost hunk on alloc error!\n");
292 							}
293 						}
294 					}
295 				} while (!skip_rest_of_patch && where == 0 &&
296 				    ++fuzz <= mymaxfuzz);
297 
298 				if (skip_rest_of_patch) {	/* just got decided */
299 					fclose(ofp);
300 					ofp = NULL;
301 				}
302 			}
303 			newwhere = pch_newfirst() + last_offset;
304 			if (skip_rest_of_patch) {
305 				abort_hunk();
306 				failed++;
307 				if (verbose)
308 					say("Hunk #%d ignored at %ld.\n",
309 					    hunk, newwhere);
310 			} else if (where == 0) {
311 				abort_hunk();
312 				failed++;
313 				if (verbose)
314 					say("Hunk #%d failed at %ld.\n",
315 					    hunk, newwhere);
316 			} else {
317 				apply_hunk(where);
318 				if (verbose) {
319 					say("Hunk #%d succeeded at %ld",
320 					    hunk, newwhere);
321 					if (fuzz != 0)
322 						say(" with fuzz %ld", fuzz);
323 					if (last_offset)
324 						say(" (offset %ld line%s)",
325 						    last_offset,
326 						    last_offset == 1L ? "" : "s");
327 					say(".\n");
328 				}
329 			}
330 		}
331 
332 		if (out_of_mem && using_plan_a) {
333 			Argc = Argc_last;
334 			Argv = Argv_last;
335 			say("\n\nRan out of memory using Plan A--trying again...\n\n");
336 			if (ofp)
337 				fclose(ofp);
338 			ofp = NULL;
339 			if (rejfp)
340 				fclose(rejfp);
341 			rejfp = NULL;
342 			continue;
343 		}
344 		if (hunk == 0)
345 			fatal("Internal error: hunk should not be 0\n");
346 
347 		/* finish spewing out the new file */
348 		if (!skip_rest_of_patch)
349 			spew_output();
350 
351 		/* and put the output where desired */
352 		ignore_signals();
353 		if (!skip_rest_of_patch) {
354 			struct stat	statbuf;
355 			char	*realout = outname;
356 
357 			if (!check_only) {
358 				if (move_file(TMPOUTNAME, outname) < 0) {
359 					toutkeep = true;
360 					realout = TMPOUTNAME;
361 					chmod(TMPOUTNAME, filemode);
362 				} else
363 					chmod(outname, filemode);
364 
365 				if (remove_empty_files &&
366 				    stat(realout, &statbuf) == 0 &&
367 				    statbuf.st_size == 0) {
368 					if (verbose)
369 						say("Removing %s (empty after patching).\n",
370 						    realout);
371 					unlink(realout);
372 				}
373 			}
374 		}
375 		fclose(rejfp);
376 		rejfp = NULL;
377 		if (failed) {
378 			error = 1;
379 			if (*rejname == '\0') {
380 				if (strlcpy(rejname, outname,
381 				    sizeof(rejname)) >= sizeof(rejname))
382 					fatal("filename %s is too long\n", outname);
383 				if (strlcat(rejname, REJEXT,
384 				    sizeof(rejname)) >= sizeof(rejname))
385 					fatal("filename %s is too long\n", outname);
386 			}
387 			if (skip_rest_of_patch) {
388 				say("%d out of %d hunks ignored--saving rejects to %s\n",
389 				    failed, hunk, rejname);
390 			} else {
391 				say("%d out of %d hunks failed--saving rejects to %s\n",
392 				    failed, hunk, rejname);
393 			}
394 			if (!check_only && move_file(TMPREJNAME, rejname) < 0)
395 				trejkeep = true;
396 		}
397 		set_signals(1);
398 	}
399 	my_exit(error);
400 	/* NOTREACHED */
401 }
402 
403 /* Prepare to find the next patch to do in the patch file. */
404 
405 static void
406 reinitialize_almost_everything(void)
407 {
408 	re_patch();
409 	re_input();
410 
411 	input_lines = 0;
412 	last_frozen_line = 0;
413 
414 	filec = 0;
415 	if (!out_of_mem) {
416 		free(filearg[0]);
417 		filearg[0] = NULL;
418 	}
419 
420 	free(outname);
421 	outname = NULL;
422 
423 	last_offset = 0;
424 	diff_type = 0;
425 
426 	free(revision);
427 	revision = NULL;
428 
429 	reverse = reverse_flag_specified;
430 	skip_rest_of_patch = false;
431 
432 	get_some_switches();
433 }
434 
435 /* Process switches and filenames. */
436 
437 static void
438 get_some_switches(void)
439 {
440 	const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
441 	static struct option longopts[] = {
442 		{"backup",		no_argument,		0,	'b'},
443 		{"batch",		no_argument,		0,	't'},
444 		{"check",		no_argument,		0,	'C'},
445 		{"context",		no_argument,		0,	'c'},
446 		{"debug",		required_argument,	0,	'x'},
447 		{"directory",		required_argument,	0,	'd'},
448 		{"ed",			no_argument,		0,	'e'},
449 		{"force",		no_argument,		0,	'f'},
450 		{"forward",		no_argument,		0,	'N'},
451 		{"fuzz",		required_argument,	0,	'F'},
452 		{"ifdef",		required_argument,	0,	'D'},
453 		{"input",		required_argument,	0,	'i'},
454 		{"ignore-whitespace",	no_argument,		0,	'l'},
455 		{"normal",		no_argument,		0,	'n'},
456 		{"output",		required_argument,	0,	'o'},
457 		{"prefix",		required_argument,	0,	'B'},
458 		{"quiet",		no_argument,		0,	's'},
459 		{"reject-file",		required_argument,	0,	'r'},
460 		{"remove-empty-files",	no_argument,		0,	'E'},
461 		{"reverse",		no_argument,		0,	'R'},
462 		{"silent",		no_argument,		0,	's'},
463 		{"strip",		required_argument,	0,	'p'},
464 		{"suffix",		required_argument,	0,	'z'},
465 		{"unified",		no_argument,		0,	'u'},
466 		{"version",		no_argument,		0,	'v'},
467 		{"version-control",	required_argument,	0,	'V'},
468 		{"posix",		no_argument,		&posix,	1},
469 		{NULL,			0,			0,	0}
470 	};
471 	int ch;
472 
473 	rejname[0] = '\0';
474 	Argc_last = Argc;
475 	Argv_last = Argv;
476 	if (!Argc)
477 		return;
478 	optreset = optind = 1;
479 	while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
480 		switch (ch) {
481 		case 'b':
482 			if (backup_type == none)
483 				backup_type = numbered_existing;
484 			if (optarg == NULL)
485 				break;
486 			if (verbose)
487 				say("Warning, the ``-b suffix'' option has been"
488 				    " obsoleted by the -z option.\n");
489 			/* FALLTHROUGH */
490 		case 'z':
491 			/* must directly follow 'b' case for backwards compat */
492 			simple_backup_suffix = savestr(optarg);
493 			break;
494 		case 'B':
495 			origprae = savestr(optarg);
496 			break;
497 		case 'c':
498 			diff_type = CONTEXT_DIFF;
499 			break;
500 		case 'C':
501 			check_only = true;
502 			break;
503 		case 'd':
504 			if (chdir(optarg) < 0)
505 				pfatal("can't cd to %s", optarg);
506 			break;
507 		case 'D':
508 			do_defines = true;
509 			if (!isalpha(*optarg) && *optarg != '_')
510 				fatal("argument to -D is not an identifier\n");
511 			snprintf(if_defined, sizeof if_defined,
512 			    "#ifdef %s\n", optarg);
513 			snprintf(not_defined, sizeof not_defined,
514 			    "#ifndef %s\n", optarg);
515 			snprintf(end_defined, sizeof end_defined,
516 			    "#endif /* %s */\n", optarg);
517 			break;
518 		case 'e':
519 			diff_type = ED_DIFF;
520 			break;
521 		case 'E':
522 			remove_empty_files = true;
523 			break;
524 		case 'f':
525 			force = true;
526 			break;
527 		case 'F':
528 			maxfuzz = atoi(optarg);
529 			break;
530 		case 'i':
531 			if (++filec == MAXFILEC)
532 				fatal("too many file arguments\n");
533 			filearg[filec] = savestr(optarg);
534 			break;
535 		case 'l':
536 			canonicalize = true;
537 			break;
538 		case 'n':
539 			diff_type = NORMAL_DIFF;
540 			break;
541 		case 'N':
542 			noreverse = true;
543 			break;
544 		case 'o':
545 			outname = savestr(optarg);
546 			break;
547 		case 'p':
548 			strippath = atoi(optarg);
549 			break;
550 		case 'r':
551 			if (strlcpy(rejname, optarg,
552 			    sizeof(rejname)) >= sizeof(rejname))
553 				fatal("argument for -r is too long\n");
554 			break;
555 		case 'R':
556 			reverse = true;
557 			reverse_flag_specified = true;
558 			break;
559 		case 's':
560 			verbose = false;
561 			break;
562 		case 't':
563 			batch = true;
564 			break;
565 		case 'u':
566 			diff_type = UNI_DIFF;
567 			break;
568 		case 'v':
569 			version();
570 			break;
571 		case 'V':
572 			backup_type = get_version(optarg);
573 			break;
574 #ifdef DEBUGGING
575 		case 'x':
576 			debug = atoi(optarg);
577 			break;
578 #endif
579 		default:
580 			if (ch != '\0')
581 				usage();
582 			break;
583 		}
584 	}
585 	Argc -= optind;
586 	Argv += optind;
587 
588 	if (Argc > 0) {
589 		filearg[0] = savestr(*Argv++);
590 		Argc--;
591 		while (Argc > 0) {
592 			if (++filec == MAXFILEC)
593 				fatal("too many file arguments\n");
594 			filearg[filec] = savestr(*Argv++);
595 			Argc--;
596 		}
597 	}
598 
599 	if (getenv("POSIXLY_CORRECT") != NULL)
600 		posix = 1;
601 }
602 
603 static __dead void
604 usage(void)
605 {
606 	fprintf(stderr,
607 "usage: patch [-bcCeEflnNRstuv] [-B backup-prefix] [-d directory] [-D symbol]\n"
608 "             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
609 "             [-r rej-name] [-V {numbered,existing,simple}] [-z backup-ext]\n"
610 "             [origfile [patchfile]]\n");
611 	my_exit(EXIT_SUCCESS);
612 }
613 
614 /*
615  * Attempt to find the right place to apply this hunk of patch.
616  */
617 static LINENUM
618 locate_hunk(LINENUM fuzz)
619 {
620 	LINENUM	first_guess = pch_first() + last_offset;
621 	LINENUM	offset;
622 	LINENUM	pat_lines = pch_ptrn_lines();
623 	LINENUM	max_pos_offset = input_lines - first_guess - pat_lines + 1;
624 	LINENUM	max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
625 
626 	if (pat_lines == 0) {		/* null range matches always */
627 		if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
628 		    || diff_type == NEW_CONTEXT_DIFF
629 		    || diff_type == UNI_DIFF)) {
630 			say("Empty context always matches.\n");
631 		}
632 		if (fuzz == 0)
633 			return (input_lines == 0 ? first_guess : 0);
634 	}
635 	if (max_neg_offset >= first_guess)	/* do not try lines < 0 */
636 		max_neg_offset = first_guess - 1;
637 	if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
638 		return first_guess;
639 	for (offset = 1; ; offset++) {
640 		bool	check_after = (offset <= max_pos_offset);
641 		bool	check_before = (offset <= max_neg_offset);
642 
643 		if (check_after && patch_match(first_guess, offset, fuzz)) {
644 #ifdef DEBUGGING
645 			if (debug & 1)
646 				say("Offset changing from %ld to %ld\n",
647 				    last_offset, offset);
648 #endif
649 			last_offset = offset;
650 			return first_guess + offset;
651 		} else if (check_before && patch_match(first_guess, -offset, fuzz)) {
652 #ifdef DEBUGGING
653 			if (debug & 1)
654 				say("Offset changing from %ld to %ld\n",
655 				    last_offset, -offset);
656 #endif
657 			last_offset = -offset;
658 			return first_guess - offset;
659 		} else if (!check_before && !check_after)
660 			return 0;
661 	}
662 }
663 
664 /* We did not find the pattern, dump out the hunk so they can handle it. */
665 
666 static void
667 abort_hunk(void)
668 {
669 	LINENUM	i;
670 	const LINENUM	pat_end = pch_end();
671 	/*
672 	 * add in last_offset to guess the same as the previous successful
673 	 * hunk
674 	 */
675 	const LINENUM	oldfirst = pch_first() + last_offset;
676 	const LINENUM	newfirst = pch_newfirst() + last_offset;
677 	const LINENUM	oldlast = oldfirst + pch_ptrn_lines() - 1;
678 	const LINENUM	newlast = newfirst + pch_repl_lines() - 1;
679 	const char	*stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
680 	const char	*minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
681 
682 	fprintf(rejfp, "***************\n");
683 	for (i = 0; i <= pat_end; i++) {
684 		switch (pch_char(i)) {
685 		case '*':
686 			if (oldlast < oldfirst)
687 				fprintf(rejfp, "*** 0%s\n", stars);
688 			else if (oldlast == oldfirst)
689 				fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
690 			else
691 				fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
692 				    oldlast, stars);
693 			break;
694 		case '=':
695 			if (newlast < newfirst)
696 				fprintf(rejfp, "--- 0%s\n", minuses);
697 			else if (newlast == newfirst)
698 				fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
699 			else
700 				fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
701 				    newlast, minuses);
702 			break;
703 		case '\n':
704 			fprintf(rejfp, "%s", pfetch(i));
705 			break;
706 		case ' ':
707 		case '-':
708 		case '+':
709 		case '!':
710 			fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
711 			break;
712 		default:
713 			fatal("fatal internal error in abort_hunk\n");
714 		}
715 	}
716 }
717 
718 /* We found where to apply it (we hope), so do it. */
719 
720 static void
721 apply_hunk(LINENUM where)
722 {
723 	LINENUM		old = 1;
724 	const LINENUM	lastline = pch_ptrn_lines();
725 	LINENUM		new = lastline + 1;
726 #define OUTSIDE 0
727 #define IN_IFNDEF 1
728 #define IN_IFDEF 2
729 #define IN_ELSE 3
730 	int		def_state = OUTSIDE;
731 	const LINENUM	pat_end = pch_end();
732 
733 	where--;
734 	while (pch_char(new) == '=' || pch_char(new) == '\n')
735 		new++;
736 
737 	while (old <= lastline) {
738 		if (pch_char(old) == '-') {
739 			copy_till(where + old - 1, false);
740 			if (do_defines) {
741 				if (def_state == OUTSIDE) {
742 					fputs(not_defined, ofp);
743 					def_state = IN_IFNDEF;
744 				} else if (def_state == IN_IFDEF) {
745 					fputs(else_defined, ofp);
746 					def_state = IN_ELSE;
747 				}
748 				fputs(pfetch(old), ofp);
749 			}
750 			last_frozen_line++;
751 			old++;
752 		} else if (new > pat_end) {
753 			break;
754 		} else if (pch_char(new) == '+') {
755 			copy_till(where + old - 1, false);
756 			if (do_defines) {
757 				if (def_state == IN_IFNDEF) {
758 					fputs(else_defined, ofp);
759 					def_state = IN_ELSE;
760 				} else if (def_state == OUTSIDE) {
761 					fputs(if_defined, ofp);
762 					def_state = IN_IFDEF;
763 				}
764 			}
765 			fputs(pfetch(new), ofp);
766 			new++;
767 		} else if (pch_char(new) != pch_char(old)) {
768 			say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
769 			    pch_hunk_beg() + old,
770 			    pch_hunk_beg() + new);
771 #ifdef DEBUGGING
772 			say("oldchar = '%c', newchar = '%c'\n",
773 			    pch_char(old), pch_char(new));
774 #endif
775 			my_exit(2);
776 		} else if (pch_char(new) == '!') {
777 			copy_till(where + old - 1, false);
778 			if (do_defines) {
779 				fputs(not_defined, ofp);
780 				def_state = IN_IFNDEF;
781 			}
782 			while (pch_char(old) == '!') {
783 				if (do_defines) {
784 					fputs(pfetch(old), ofp);
785 				}
786 				last_frozen_line++;
787 				old++;
788 			}
789 			if (do_defines) {
790 				fputs(else_defined, ofp);
791 				def_state = IN_ELSE;
792 			}
793 			while (pch_char(new) == '!') {
794 				fputs(pfetch(new), ofp);
795 				new++;
796 			}
797 		} else {
798 			if (pch_char(new) != ' ')
799 				fatal("Internal error: expected ' '\n");
800 			old++;
801 			new++;
802 			if (do_defines && def_state != OUTSIDE) {
803 				fputs(end_defined, ofp);
804 				def_state = OUTSIDE;
805 			}
806 		}
807 	}
808 	if (new <= pat_end && pch_char(new) == '+') {
809 		copy_till(where + old - 1, false);
810 		if (do_defines) {
811 			if (def_state == OUTSIDE) {
812 				fputs(if_defined, ofp);
813 				def_state = IN_IFDEF;
814 			} else if (def_state == IN_IFNDEF) {
815 				fputs(else_defined, ofp);
816 				def_state = IN_ELSE;
817 			}
818 		}
819 		while (new <= pat_end && pch_char(new) == '+') {
820 			fputs(pfetch(new), ofp);
821 			new++;
822 		}
823 	}
824 	if (do_defines && def_state != OUTSIDE) {
825 		fputs(end_defined, ofp);
826 	}
827 }
828 
829 /*
830  * Open the new file.
831  */
832 static void
833 init_output(const char *name)
834 {
835 	ofp = fopen(name, "w");
836 	if (ofp == NULL)
837 		pfatal("can't create %s", name);
838 }
839 
840 /*
841  * Open a file to put hunks we can't locate.
842  */
843 static void
844 init_reject(const char *name)
845 {
846 	rejfp = fopen(name, "w");
847 	if (rejfp == NULL)
848 		pfatal("can't create %s", name);
849 }
850 
851 /*
852  * Copy input file to output, up to wherever hunk is to be applied.
853  * If endoffile is true, treat the last line specially since it may
854  * lack a newline.
855  */
856 static void
857 copy_till(LINENUM lastline, bool endoffile)
858 {
859 	if (last_frozen_line > lastline)
860 		fatal("misordered hunks! output would be garbled\n");
861 	while (last_frozen_line < lastline) {
862 		if (++last_frozen_line == lastline && endoffile)
863 			dump_line(last_frozen_line, !last_line_missing_eol);
864 		else
865 			dump_line(last_frozen_line, true);
866 	}
867 }
868 
869 /*
870  * Finish copying the input file to the output file.
871  */
872 static void
873 spew_output(void)
874 {
875 #ifdef DEBUGGING
876 	if (debug & 256)
877 		say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
878 #endif
879 	if (input_lines)
880 		copy_till(input_lines, true);	/* dump remainder of file */
881 	fclose(ofp);
882 	ofp = NULL;
883 }
884 
885 /*
886  * Copy one line from input to output.
887  */
888 static void
889 dump_line(LINENUM line, bool write_newline)
890 {
891 	char	*s;
892 
893 	s = ifetch(line, 0);
894 	if (s == NULL)
895 		return;
896 	/* Note: string is not NUL terminated. */
897 	for (; *s != '\n'; s++)
898 		putc(*s, ofp);
899 	if (write_newline)
900 		putc('\n', ofp);
901 }
902 
903 /*
904  * Does the patch pattern match at line base+offset?
905  */
906 static bool
907 patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
908 {
909 	LINENUM		pline = 1 + fuzz;
910 	LINENUM		iline;
911 	LINENUM		pat_lines = pch_ptrn_lines() - fuzz;
912 	const char	*ilineptr;
913 	const char	*plineptr;
914 	short		plinelen;
915 
916 	for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
917 		ilineptr = ifetch(iline, offset >= 0);
918 		if (ilineptr == NULL)
919 			return false;
920 		plineptr = pfetch(pline);
921 		plinelen = pch_line_len(pline);
922 		if (canonicalize) {
923 			if (!similar(ilineptr, plineptr, plinelen))
924 				return false;
925 		} else if (strnNE(ilineptr, plineptr, plinelen))
926 			return false;
927 	}
928 	return true;
929 }
930 
931 /*
932  * Do two lines match with canonicalized white space?
933  */
934 static bool
935 similar(const char *a, const char *b, int len)
936 {
937 	while (len) {
938 		if (isspace(*b)) {	/* whitespace (or \n) to match? */
939 			if (!isspace(*a))	/* no corresponding whitespace? */
940 				return false;
941 			while (len && isspace(*b) && *b != '\n')
942 				b++, len--;	/* skip pattern whitespace */
943 			while (isspace(*a) && *a != '\n')
944 				a++;	/* skip target whitespace */
945 			if (*a == '\n' || *b == '\n')
946 				return (*a == *b);	/* should end in sync */
947 		} else if (*a++ != *b++)	/* match non-whitespace chars */
948 			return false;
949 		else
950 			len--;	/* probably not necessary */
951 	}
952 	return true;		/* actually, this is not reached */
953 	/* since there is always a \n */
954 }
955