xref: /freebsd/usr.bin/patch/patch.c (revision 6e660824a82f590542932de52f128db584029893)
1 /*-
2  * Copyright 1986, Larry Wall
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following condition is met:
6  * 1. Redistributions of source code must retain the above copyright notice,
7  * this condition and the following disclaimer.
8  *
9  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
10  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
11  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
12  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
13  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
14  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
15  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
16  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
17  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
18  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
19  * SUCH DAMAGE.
20  *
21  * patch - a program to apply diffs to original files
22  *
23  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
24  * behaviour
25  *
26  * $OpenBSD: patch.c,v 1.50 2012/05/15 19:32:02 millert Exp $
27  * $FreeBSD$
28  *
29  */
30 
31 #include <sys/types.h>
32 #include <sys/stat.h>
33 
34 #include <ctype.h>
35 #include <getopt.h>
36 #include <limits.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41 
42 #include "common.h"
43 #include "util.h"
44 #include "pch.h"
45 #include "inp.h"
46 #include "backupfile.h"
47 #include "pathnames.h"
48 
49 mode_t		filemode = 0644;
50 
51 char		*buf;			/* general purpose buffer */
52 size_t		buf_size;		/* size of the general purpose buffer */
53 
54 bool		using_plan_a = true;	/* try to keep everything in memory */
55 bool		out_of_mem = false;	/* ran out of memory in plan a */
56 
57 #define MAXFILEC 2
58 
59 char		*filearg[MAXFILEC];
60 bool		ok_to_create_file = false;
61 char		*outname = NULL;
62 char		*origprae = NULL;
63 char		*TMPOUTNAME;
64 char		*TMPINNAME;
65 char		*TMPREJNAME;
66 char		*TMPPATNAME;
67 bool		toutkeep = false;
68 bool		trejkeep = false;
69 bool		warn_on_invalid_line;
70 bool		last_line_missing_eol;
71 
72 #ifdef DEBUGGING
73 int		debug = 0;
74 #endif
75 
76 bool		force = false;
77 bool		batch = false;
78 bool		verbose = true;
79 bool		reverse = false;
80 bool		noreverse = false;
81 bool		skip_rest_of_patch = false;
82 int		strippath = 957;
83 bool		canonicalize = false;
84 bool		check_only = false;
85 int		diff_type = 0;
86 char		*revision = NULL;	/* prerequisite revision, if any */
87 LINENUM		input_lines = 0;	/* how long is input file in lines */
88 int		posix = 0;		/* strict POSIX mode? */
89 
90 static void	reinitialize_almost_everything(void);
91 static void	get_some_switches(void);
92 static LINENUM	locate_hunk(LINENUM);
93 static void	abort_context_hunk(void);
94 static void	rej_line(int, LINENUM);
95 static void	abort_hunk(void);
96 static void	apply_hunk(LINENUM);
97 static void	init_output(const char *);
98 static void	init_reject(const char *);
99 static void	copy_till(LINENUM, bool);
100 static bool	spew_output(void);
101 static void	dump_line(LINENUM, bool);
102 static bool	patch_match(LINENUM, LINENUM, LINENUM);
103 static bool	similar(const char *, const char *, int);
104 static void	usage(void);
105 
106 /* true if -E was specified on command line.  */
107 static bool	remove_empty_files = false;
108 
109 /* true if -R was specified on command line.  */
110 static bool	reverse_flag_specified = false;
111 
112 /* buffer holding the name of the rejected patch file. */
113 static char	rejname[NAME_MAX + 1];
114 
115 /* how many input lines have been irretractibly output */
116 static LINENUM	last_frozen_line = 0;
117 
118 static int	Argc;		/* guess */
119 static char	**Argv;
120 static int	Argc_last;	/* for restarting plan_b */
121 static char	**Argv_last;
122 
123 static FILE	*ofp = NULL;	/* output file pointer */
124 static FILE	*rejfp = NULL;	/* reject file pointer */
125 
126 static int	filec = 0;	/* how many file arguments? */
127 static LINENUM	last_offset = 0;
128 static LINENUM	maxfuzz = 2;
129 
130 /* patch using ifdef, ifndef, etc. */
131 static bool		do_defines = false;
132 /* #ifdef xyzzy */
133 static char		if_defined[128];
134 /* #ifndef xyzzy */
135 static char		not_defined[128];
136 /* #else */
137 static const char	else_defined[] = "#else\n";
138 /* #endif xyzzy */
139 static char		end_defined[128];
140 
141 
142 /* Apply a set of diffs as appropriate. */
143 
144 int
145 main(int argc, char *argv[])
146 {
147 	int	error = 0, hunk, failed, i, fd;
148 	bool	patch_seen;
149 	LINENUM	where = 0, newwhere, fuzz, mymaxfuzz;
150 	const	char *tmpdir;
151 	char	*v;
152 
153 	setlinebuf(stdout);
154 	setlinebuf(stderr);
155 	for (i = 0; i < MAXFILEC; i++)
156 		filearg[i] = NULL;
157 
158 	buf_size = INITLINELEN;
159 	buf = malloc((unsigned)(buf_size));
160 	if (buf == NULL)
161 		fatal("out of memory\n");
162 
163 	/* Cons up the names of the temporary files.  */
164 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
165 		tmpdir = _PATH_TMP;
166 	for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
167 		;
168 	i++;
169 	if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
170 		fatal("cannot allocate memory");
171 	if ((fd = mkstemp(TMPOUTNAME)) < 0)
172 		pfatal("can't create %s", TMPOUTNAME);
173 	close(fd);
174 
175 	if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
176 		fatal("cannot allocate memory");
177 	if ((fd = mkstemp(TMPINNAME)) < 0)
178 		pfatal("can't create %s", TMPINNAME);
179 	close(fd);
180 
181 	if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
182 		fatal("cannot allocate memory");
183 	if ((fd = mkstemp(TMPREJNAME)) < 0)
184 		pfatal("can't create %s", TMPREJNAME);
185 	close(fd);
186 
187 	if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
188 		fatal("cannot allocate memory");
189 	if ((fd = mkstemp(TMPPATNAME)) < 0)
190 		pfatal("can't create %s", TMPPATNAME);
191 	close(fd);
192 
193 	v = getenv("SIMPLE_BACKUP_SUFFIX");
194 	if (v)
195 		simple_backup_suffix = v;
196 	else
197 		simple_backup_suffix = ORIGEXT;
198 
199 	/* parse switches */
200 	Argc = argc;
201 	Argv = argv;
202 	get_some_switches();
203 
204 	if (backup_type == none) {
205 		if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
206 			v = getenv("VERSION_CONTROL");
207 		if (v != NULL || !posix)
208 			backup_type = get_version(v);	/* OK to pass NULL. */
209 	}
210 
211 	/* make sure we clean up /tmp in case of disaster */
212 	set_signals(0);
213 
214 	patch_seen = false;
215 	for (open_patch_file(filearg[1]); there_is_another_patch();
216 	    reinitialize_almost_everything()) {
217 		/* for each patch in patch file */
218 
219 		patch_seen = true;
220 
221 		warn_on_invalid_line = true;
222 
223 		if (outname == NULL)
224 			outname = savestr(filearg[0]);
225 
226 		/* for ed script just up and do it and exit */
227 		if (diff_type == ED_DIFF) {
228 			do_ed_script();
229 			continue;
230 		}
231 		/* initialize the patched file */
232 		if (!skip_rest_of_patch)
233 			init_output(TMPOUTNAME);
234 
235 		/* initialize reject file */
236 		init_reject(TMPREJNAME);
237 
238 		/* find out where all the lines are */
239 		if (!skip_rest_of_patch)
240 			scan_input(filearg[0]);
241 
242 		/*
243 		 * from here on, open no standard i/o files, because
244 		 * malloc might misfire and we can't catch it easily
245 		 */
246 
247 		/* apply each hunk of patch */
248 		hunk = 0;
249 		failed = 0;
250 		out_of_mem = false;
251 		while (another_hunk()) {
252 			hunk++;
253 			fuzz = 0;
254 			mymaxfuzz = pch_context();
255 			if (maxfuzz < mymaxfuzz)
256 				mymaxfuzz = maxfuzz;
257 			if (!skip_rest_of_patch) {
258 				do {
259 					where = locate_hunk(fuzz);
260 					if (hunk == 1 && where == 0 && !force) {
261 						/* dwim for reversed patch? */
262 						if (!pch_swap()) {
263 							if (fuzz == 0)
264 								say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
265 							continue;
266 						}
267 						reverse = !reverse;
268 						/* try again */
269 						where = locate_hunk(fuzz);
270 						if (where == 0) {
271 							/* didn't find it swapped */
272 							if (!pch_swap())
273 								/* put it back to normal */
274 								fatal("lost hunk on alloc error!\n");
275 							reverse = !reverse;
276 						} else if (noreverse) {
277 							if (!pch_swap())
278 								/* put it back to normal */
279 								fatal("lost hunk on alloc error!\n");
280 							reverse = !reverse;
281 							say("Ignoring previously applied (or reversed) patch.\n");
282 							skip_rest_of_patch = true;
283 						} else if (batch) {
284 							if (verbose)
285 								say("%seversed (or previously applied) patch detected!  %s -R.",
286 								    reverse ? "R" : "Unr",
287 								    reverse ? "Assuming" : "Ignoring");
288 						} else {
289 							ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
290 							    reverse ? "R" : "Unr",
291 							    reverse ? "Assume" : "Ignore");
292 							if (*buf == 'n') {
293 								ask("Apply anyway? [n] ");
294 								if (*buf != 'y')
295 									skip_rest_of_patch = true;
296 								where = 0;
297 								reverse = !reverse;
298 								if (!pch_swap())
299 									/* put it back to normal */
300 									fatal("lost hunk on alloc error!\n");
301 							}
302 						}
303 					}
304 				} while (!skip_rest_of_patch && where == 0 &&
305 				    ++fuzz <= mymaxfuzz);
306 
307 				if (skip_rest_of_patch) {	/* just got decided */
308 					if (ferror(ofp) || fclose(ofp)) {
309 						say("Error writing %s\n",
310 						    TMPOUTNAME);
311 						error = 1;
312 					}
313 					ofp = NULL;
314 				}
315 			}
316 			newwhere = pch_newfirst() + last_offset;
317 			if (skip_rest_of_patch) {
318 				abort_hunk();
319 				failed++;
320 				if (verbose)
321 					say("Hunk #%d ignored at %ld.\n",
322 					    hunk, newwhere);
323 			} else if (where == 0) {
324 				abort_hunk();
325 				failed++;
326 				if (verbose)
327 					say("Hunk #%d failed at %ld.\n",
328 					    hunk, newwhere);
329 			} else {
330 				apply_hunk(where);
331 				if (verbose) {
332 					say("Hunk #%d succeeded at %ld",
333 					    hunk, newwhere);
334 					if (fuzz != 0)
335 						say(" with fuzz %ld", fuzz);
336 					if (last_offset)
337 						say(" (offset %ld line%s)",
338 						    last_offset,
339 						    last_offset == 1L ? "" : "s");
340 					say(".\n");
341 				}
342 			}
343 		}
344 
345 		if (out_of_mem && using_plan_a) {
346 			Argc = Argc_last;
347 			Argv = Argv_last;
348 			say("\n\nRan out of memory using Plan A--trying again...\n\n");
349 			if (ofp)
350 				fclose(ofp);
351 			ofp = NULL;
352 			if (rejfp)
353 				fclose(rejfp);
354 			rejfp = NULL;
355 			continue;
356 		}
357 		if (hunk == 0)
358 			fatal("Internal error: hunk should not be 0\n");
359 
360 		/* finish spewing out the new file */
361 		if (!skip_rest_of_patch && !spew_output()) {
362 			say("Can't write %s\n", TMPOUTNAME);
363 			error = 1;
364 		}
365 
366 		/* and put the output where desired */
367 		ignore_signals();
368 		if (!skip_rest_of_patch) {
369 			struct stat	statbuf;
370 			char	*realout = outname;
371 
372 			if (!check_only) {
373 				if (move_file(TMPOUTNAME, outname) < 0) {
374 					toutkeep = true;
375 					realout = TMPOUTNAME;
376 					chmod(TMPOUTNAME, filemode);
377 				} else
378 					chmod(outname, filemode);
379 
380 				if (remove_empty_files &&
381 				    stat(realout, &statbuf) == 0 &&
382 				    statbuf.st_size == 0) {
383 					if (verbose)
384 						say("Removing %s (empty after patching).\n",
385 						    realout);
386 					unlink(realout);
387 				}
388 			}
389 		}
390 		if (ferror(rejfp) || fclose(rejfp)) {
391 			say("Error writing %s\n", rejname);
392 			error = 1;
393 		}
394 		rejfp = NULL;
395 		if (failed) {
396 			error = 1;
397 			if (*rejname == '\0') {
398 				if (strlcpy(rejname, outname,
399 				    sizeof(rejname)) >= sizeof(rejname))
400 					fatal("filename %s is too long\n", outname);
401 				if (strlcat(rejname, REJEXT,
402 				    sizeof(rejname)) >= sizeof(rejname))
403 					fatal("filename %s is too long\n", outname);
404 			}
405 			if (!check_only)
406 				say("%d out of %d hunks %s--saving rejects to %s\n",
407 				    failed, hunk, skip_rest_of_patch ? "ignored" : "failed", rejname);
408 			else
409 				say("%d out of %d hunks %s\n",
410 				    failed, hunk, skip_rest_of_patch ? "ignored" : "failed");
411 			if (!check_only && move_file(TMPREJNAME, rejname) < 0)
412 				trejkeep = true;
413 		}
414 		set_signals(1);
415 	}
416 
417 	if (!patch_seen)
418 		error = 2;
419 
420 	my_exit(error);
421 	/* NOTREACHED */
422 }
423 
424 /* Prepare to find the next patch to do in the patch file. */
425 
426 static void
427 reinitialize_almost_everything(void)
428 {
429 	re_patch();
430 	re_input();
431 
432 	input_lines = 0;
433 	last_frozen_line = 0;
434 
435 	filec = 0;
436 	if (!out_of_mem) {
437 		free(filearg[0]);
438 		filearg[0] = NULL;
439 	}
440 
441 	free(outname);
442 	outname = NULL;
443 
444 	last_offset = 0;
445 	diff_type = 0;
446 
447 	free(revision);
448 	revision = NULL;
449 
450 	reverse = reverse_flag_specified;
451 	skip_rest_of_patch = false;
452 
453 	get_some_switches();
454 }
455 
456 /* Process switches and filenames. */
457 
458 static void
459 get_some_switches(void)
460 {
461 	const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
462 	static struct option longopts[] = {
463 		{"backup",		no_argument,		0,	'b'},
464 		{"batch",		no_argument,		0,	't'},
465 		{"check",		no_argument,		0,	'C'},
466 		{"context",		no_argument,		0,	'c'},
467 		{"debug",		required_argument,	0,	'x'},
468 		{"directory",		required_argument,	0,	'd'},
469 		{"ed",			no_argument,		0,	'e'},
470 		{"force",		no_argument,		0,	'f'},
471 		{"forward",		no_argument,		0,	'N'},
472 		{"fuzz",		required_argument,	0,	'F'},
473 		{"ifdef",		required_argument,	0,	'D'},
474 		{"input",		required_argument,	0,	'i'},
475 		{"ignore-whitespace",	no_argument,		0,	'l'},
476 		{"normal",		no_argument,		0,	'n'},
477 		{"output",		required_argument,	0,	'o'},
478 		{"prefix",		required_argument,	0,	'B'},
479 		{"quiet",		no_argument,		0,	's'},
480 		{"reject-file",		required_argument,	0,	'r'},
481 		{"remove-empty-files",	no_argument,		0,	'E'},
482 		{"reverse",		no_argument,		0,	'R'},
483 		{"silent",		no_argument,		0,	's'},
484 		{"strip",		required_argument,	0,	'p'},
485 		{"suffix",		required_argument,	0,	'z'},
486 		{"unified",		no_argument,		0,	'u'},
487 		{"version",		no_argument,		0,	'v'},
488 		{"version-control",	required_argument,	0,	'V'},
489 		{"posix",		no_argument,		&posix,	1},
490 		{NULL,			0,			0,	0}
491 	};
492 	int ch;
493 
494 	rejname[0] = '\0';
495 	Argc_last = Argc;
496 	Argv_last = Argv;
497 	if (!Argc)
498 		return;
499 	optreset = optind = 1;
500 	while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
501 		switch (ch) {
502 		case 'b':
503 			if (backup_type == none)
504 				backup_type = numbered_existing;
505 			if (optarg == NULL)
506 				break;
507 			if (verbose)
508 				say("Warning, the ``-b suffix'' option has been"
509 				    " obsoleted by the -z option.\n");
510 			/* FALLTHROUGH */
511 		case 'z':
512 			/* must directly follow 'b' case for backwards compat */
513 			simple_backup_suffix = savestr(optarg);
514 			break;
515 		case 'B':
516 			origprae = savestr(optarg);
517 			break;
518 		case 'c':
519 			diff_type = CONTEXT_DIFF;
520 			break;
521 		case 'C':
522 			check_only = true;
523 			break;
524 		case 'd':
525 			if (chdir(optarg) < 0)
526 				pfatal("can't cd to %s", optarg);
527 			break;
528 		case 'D':
529 			do_defines = true;
530 			if (!isalpha((unsigned char)*optarg) && *optarg != '_')
531 				fatal("argument to -D is not an identifier\n");
532 			snprintf(if_defined, sizeof if_defined,
533 			    "#ifdef %s\n", optarg);
534 			snprintf(not_defined, sizeof not_defined,
535 			    "#ifndef %s\n", optarg);
536 			snprintf(end_defined, sizeof end_defined,
537 			    "#endif /* %s */\n", optarg);
538 			break;
539 		case 'e':
540 			diff_type = ED_DIFF;
541 			break;
542 		case 'E':
543 			remove_empty_files = true;
544 			break;
545 		case 'f':
546 			force = true;
547 			break;
548 		case 'F':
549 			maxfuzz = atoi(optarg);
550 			break;
551 		case 'i':
552 			if (++filec == MAXFILEC)
553 				fatal("too many file arguments\n");
554 			filearg[filec] = savestr(optarg);
555 			break;
556 		case 'l':
557 			canonicalize = true;
558 			break;
559 		case 'n':
560 			diff_type = NORMAL_DIFF;
561 			break;
562 		case 'N':
563 			noreverse = true;
564 			break;
565 		case 'o':
566 			outname = savestr(optarg);
567 			break;
568 		case 'p':
569 			strippath = atoi(optarg);
570 			break;
571 		case 'r':
572 			if (strlcpy(rejname, optarg,
573 			    sizeof(rejname)) >= sizeof(rejname))
574 				fatal("argument for -r is too long\n");
575 			break;
576 		case 'R':
577 			reverse = true;
578 			reverse_flag_specified = true;
579 			break;
580 		case 's':
581 			verbose = false;
582 			break;
583 		case 't':
584 			batch = true;
585 			break;
586 		case 'u':
587 			diff_type = UNI_DIFF;
588 			break;
589 		case 'v':
590 			version();
591 			break;
592 		case 'V':
593 			backup_type = get_version(optarg);
594 			break;
595 #ifdef DEBUGGING
596 		case 'x':
597 			debug = atoi(optarg);
598 			break;
599 #endif
600 		default:
601 			if (ch != '\0')
602 				usage();
603 			break;
604 		}
605 	}
606 	Argc -= optind;
607 	Argv += optind;
608 
609 	if (Argc > 0) {
610 		filearg[0] = savestr(*Argv++);
611 		Argc--;
612 		while (Argc > 0) {
613 			if (++filec == MAXFILEC)
614 				fatal("too many file arguments\n");
615 			filearg[filec] = savestr(*Argv++);
616 			Argc--;
617 		}
618 	}
619 
620 	if (getenv("POSIXLY_CORRECT") != NULL)
621 		posix = 1;
622 }
623 
624 static void
625 usage(void)
626 {
627 	fprintf(stderr,
628 "usage: patch [-bCcEeflNnRstuv] [-B backup-prefix] [-D symbol] [-d directory]\n"
629 "             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
630 "             [-r rej-name] [-V t | nil | never] [-x number] [-z backup-ext]\n"
631 "             [--posix] [origfile [patchfile]]\n"
632 "       patch <patchfile\n");
633 	my_exit(EXIT_SUCCESS);
634 }
635 
636 /*
637  * Attempt to find the right place to apply this hunk of patch.
638  */
639 static LINENUM
640 locate_hunk(LINENUM fuzz)
641 {
642 	LINENUM	first_guess = pch_first() + last_offset;
643 	LINENUM	offset;
644 	LINENUM	pat_lines = pch_ptrn_lines();
645 	LINENUM	max_pos_offset = input_lines - first_guess - pat_lines + 1;
646 	LINENUM	max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
647 
648 	if (pat_lines == 0) {		/* null range matches always */
649 		if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
650 		    || diff_type == NEW_CONTEXT_DIFF
651 		    || diff_type == UNI_DIFF)) {
652 			say("Empty context always matches.\n");
653 		}
654 		return (first_guess);
655 	}
656 	if (max_neg_offset >= first_guess)	/* do not try lines < 0 */
657 		max_neg_offset = first_guess - 1;
658 	if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
659 		return first_guess;
660 	for (offset = 1; ; offset++) {
661 		bool	check_after = (offset <= max_pos_offset);
662 		bool	check_before = (offset <= max_neg_offset);
663 
664 		if (check_after && patch_match(first_guess, offset, fuzz)) {
665 #ifdef DEBUGGING
666 			if (debug & 1)
667 				say("Offset changing from %ld to %ld\n",
668 				    last_offset, offset);
669 #endif
670 			last_offset = offset;
671 			return first_guess + offset;
672 		} else if (check_before && patch_match(first_guess, -offset, fuzz)) {
673 #ifdef DEBUGGING
674 			if (debug & 1)
675 				say("Offset changing from %ld to %ld\n",
676 				    last_offset, -offset);
677 #endif
678 			last_offset = -offset;
679 			return first_guess - offset;
680 		} else if (!check_before && !check_after)
681 			return 0;
682 	}
683 }
684 
685 /* We did not find the pattern, dump out the hunk so they can handle it. */
686 
687 static void
688 abort_context_hunk(void)
689 {
690 	LINENUM	i;
691 	const LINENUM	pat_end = pch_end();
692 	/*
693 	 * add in last_offset to guess the same as the previous successful
694 	 * hunk
695 	 */
696 	const LINENUM	oldfirst = pch_first() + last_offset;
697 	const LINENUM	newfirst = pch_newfirst() + last_offset;
698 	const LINENUM	oldlast = oldfirst + pch_ptrn_lines() - 1;
699 	const LINENUM	newlast = newfirst + pch_repl_lines() - 1;
700 	const char	*stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
701 	const char	*minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
702 
703 	fprintf(rejfp, "***************\n");
704 	for (i = 0; i <= pat_end; i++) {
705 		switch (pch_char(i)) {
706 		case '*':
707 			if (oldlast < oldfirst)
708 				fprintf(rejfp, "*** 0%s\n", stars);
709 			else if (oldlast == oldfirst)
710 				fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
711 			else
712 				fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
713 				    oldlast, stars);
714 			break;
715 		case '=':
716 			if (newlast < newfirst)
717 				fprintf(rejfp, "--- 0%s\n", minuses);
718 			else if (newlast == newfirst)
719 				fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
720 			else
721 				fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
722 				    newlast, minuses);
723 			break;
724 		case '\n':
725 			fprintf(rejfp, "%s", pfetch(i));
726 			break;
727 		case ' ':
728 		case '-':
729 		case '+':
730 		case '!':
731 			fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
732 			break;
733 		default:
734 			fatal("fatal internal error in abort_context_hunk\n");
735 		}
736 	}
737 }
738 
739 static void
740 rej_line(int ch, LINENUM i)
741 {
742 	size_t len;
743 	const char *line = pfetch(i);
744 
745 	len = strlen(line);
746 
747 	fprintf(rejfp, "%c%s", ch, line);
748 	if (len == 0 || line[len-1] != '\n')
749 		fprintf(rejfp, "\n\\ No newline at end of file\n");
750 }
751 
752 static void
753 abort_hunk(void)
754 {
755 	LINENUM		i, j, split;
756 	int		ch1, ch2;
757 	const LINENUM	pat_end = pch_end();
758 	const LINENUM	oldfirst = pch_first() + last_offset;
759 	const LINENUM	newfirst = pch_newfirst() + last_offset;
760 
761 	if (diff_type != UNI_DIFF) {
762 		abort_context_hunk();
763 		return;
764 	}
765 	split = -1;
766 	for (i = 0; i <= pat_end; i++) {
767 		if (pch_char(i) == '=') {
768 			split = i;
769 			break;
770 		}
771 	}
772 	if (split == -1) {
773 		fprintf(rejfp, "malformed hunk: no split found\n");
774 		return;
775 	}
776 	i = 0;
777 	j = split + 1;
778 	fprintf(rejfp, "@@ -%ld,%ld +%ld,%ld @@\n",
779 	    pch_ptrn_lines() ? oldfirst : 0,
780 	    pch_ptrn_lines(), newfirst, pch_repl_lines());
781 	while (i < split || j <= pat_end) {
782 		ch1 = i < split ? pch_char(i) : -1;
783 		ch2 = j <= pat_end ? pch_char(j) : -1;
784 		if (ch1 == '-') {
785 			rej_line('-', i);
786 			i++;
787 		} else if (ch1 == ' ' && ch2 == ' ') {
788 			rej_line(' ', i);
789 			i++;
790 			j++;
791 		} else if (ch1 == '!' && ch2 == '!') {
792 			while (i < split && ch1 == '!') {
793 				rej_line('-', i);
794 				i++;
795 				ch1 = i < split ? pch_char(i) : -1;
796 			}
797 			while (j <= pat_end && ch2 == '!') {
798 				rej_line('+', j);
799 				j++;
800 				ch2 = j <= pat_end ? pch_char(j) : -1;
801 			}
802 		} else if (ch1 == '*') {
803 			i++;
804 		} else if (ch2 == '+' || ch2 == ' ') {
805 			rej_line(ch2, j);
806 			j++;
807 		} else {
808 			fprintf(rejfp, "internal error on (%ld %ld %ld)\n",
809 			    i, split, j);
810 			rej_line(ch1, i);
811 			rej_line(ch2, j);
812 			return;
813 		}
814 	}
815 }
816 
817 /* We found where to apply it (we hope), so do it. */
818 
819 static void
820 apply_hunk(LINENUM where)
821 {
822 	LINENUM		old = 1;
823 	const LINENUM	lastline = pch_ptrn_lines();
824 	LINENUM		new = lastline + 1;
825 #define OUTSIDE 0
826 #define IN_IFNDEF 1
827 #define IN_IFDEF 2
828 #define IN_ELSE 3
829 	int		def_state = OUTSIDE;
830 	const LINENUM	pat_end = pch_end();
831 
832 	where--;
833 	while (pch_char(new) == '=' || pch_char(new) == '\n')
834 		new++;
835 
836 	while (old <= lastline) {
837 		if (pch_char(old) == '-') {
838 			copy_till(where + old - 1, false);
839 			if (do_defines) {
840 				if (def_state == OUTSIDE) {
841 					fputs(not_defined, ofp);
842 					def_state = IN_IFNDEF;
843 				} else if (def_state == IN_IFDEF) {
844 					fputs(else_defined, ofp);
845 					def_state = IN_ELSE;
846 				}
847 				fputs(pfetch(old), ofp);
848 			}
849 			last_frozen_line++;
850 			old++;
851 		} else if (new > pat_end) {
852 			break;
853 		} else if (pch_char(new) == '+') {
854 			copy_till(where + old - 1, false);
855 			if (do_defines) {
856 				if (def_state == IN_IFNDEF) {
857 					fputs(else_defined, ofp);
858 					def_state = IN_ELSE;
859 				} else if (def_state == OUTSIDE) {
860 					fputs(if_defined, ofp);
861 					def_state = IN_IFDEF;
862 				}
863 			}
864 			fputs(pfetch(new), ofp);
865 			new++;
866 		} else if (pch_char(new) != pch_char(old)) {
867 			say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
868 			    pch_hunk_beg() + old,
869 			    pch_hunk_beg() + new);
870 #ifdef DEBUGGING
871 			say("oldchar = '%c', newchar = '%c'\n",
872 			    pch_char(old), pch_char(new));
873 #endif
874 			my_exit(2);
875 		} else if (pch_char(new) == '!') {
876 			copy_till(where + old - 1, false);
877 			if (do_defines) {
878 				fputs(not_defined, ofp);
879 				def_state = IN_IFNDEF;
880 			}
881 			while (pch_char(old) == '!') {
882 				if (do_defines) {
883 					fputs(pfetch(old), ofp);
884 				}
885 				last_frozen_line++;
886 				old++;
887 			}
888 			if (do_defines) {
889 				fputs(else_defined, ofp);
890 				def_state = IN_ELSE;
891 			}
892 			while (pch_char(new) == '!') {
893 				fputs(pfetch(new), ofp);
894 				new++;
895 			}
896 		} else {
897 			if (pch_char(new) != ' ')
898 				fatal("Internal error: expected ' '\n");
899 			old++;
900 			new++;
901 			if (do_defines && def_state != OUTSIDE) {
902 				fputs(end_defined, ofp);
903 				def_state = OUTSIDE;
904 			}
905 		}
906 	}
907 	if (new <= pat_end && pch_char(new) == '+') {
908 		copy_till(where + old - 1, false);
909 		if (do_defines) {
910 			if (def_state == OUTSIDE) {
911 				fputs(if_defined, ofp);
912 				def_state = IN_IFDEF;
913 			} else if (def_state == IN_IFNDEF) {
914 				fputs(else_defined, ofp);
915 				def_state = IN_ELSE;
916 			}
917 		}
918 		while (new <= pat_end && pch_char(new) == '+') {
919 			fputs(pfetch(new), ofp);
920 			new++;
921 		}
922 	}
923 	if (do_defines && def_state != OUTSIDE) {
924 		fputs(end_defined, ofp);
925 	}
926 }
927 
928 /*
929  * Open the new file.
930  */
931 static void
932 init_output(const char *name)
933 {
934 	ofp = fopen(name, "w");
935 	if (ofp == NULL)
936 		pfatal("can't create %s", name);
937 }
938 
939 /*
940  * Open a file to put hunks we can't locate.
941  */
942 static void
943 init_reject(const char *name)
944 {
945 	rejfp = fopen(name, "w");
946 	if (rejfp == NULL)
947 		pfatal("can't create %s", name);
948 }
949 
950 /*
951  * Copy input file to output, up to wherever hunk is to be applied.
952  * If endoffile is true, treat the last line specially since it may
953  * lack a newline.
954  */
955 static void
956 copy_till(LINENUM lastline, bool endoffile)
957 {
958 	if (last_frozen_line > lastline)
959 		fatal("misordered hunks! output would be garbled\n");
960 	while (last_frozen_line < lastline) {
961 		if (++last_frozen_line == lastline && endoffile)
962 			dump_line(last_frozen_line, !last_line_missing_eol);
963 		else
964 			dump_line(last_frozen_line, true);
965 	}
966 }
967 
968 /*
969  * Finish copying the input file to the output file.
970  */
971 static bool
972 spew_output(void)
973 {
974 	int rv;
975 
976 #ifdef DEBUGGING
977 	if (debug & 256)
978 		say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
979 #endif
980 	if (input_lines)
981 		copy_till(input_lines, true);	/* dump remainder of file */
982 	rv = ferror(ofp) == 0 && fclose(ofp) == 0;
983 	ofp = NULL;
984 	return rv;
985 }
986 
987 /*
988  * Copy one line from input to output.
989  */
990 static void
991 dump_line(LINENUM line, bool write_newline)
992 {
993 	char	*s;
994 
995 	s = ifetch(line, 0);
996 	if (s == NULL)
997 		return;
998 	/* Note: string is not NUL terminated. */
999 	for (; *s != '\n'; s++)
1000 		putc(*s, ofp);
1001 	if (write_newline)
1002 		putc('\n', ofp);
1003 }
1004 
1005 /*
1006  * Does the patch pattern match at line base+offset?
1007  */
1008 static bool
1009 patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
1010 {
1011 	LINENUM		pline = 1 + fuzz;
1012 	LINENUM		iline;
1013 	LINENUM		pat_lines = pch_ptrn_lines() - fuzz;
1014 	const char	*ilineptr;
1015 	const char	*plineptr;
1016 	short		plinelen;
1017 
1018 	for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
1019 		ilineptr = ifetch(iline, offset >= 0);
1020 		if (ilineptr == NULL)
1021 			return false;
1022 		plineptr = pfetch(pline);
1023 		plinelen = pch_line_len(pline);
1024 		if (canonicalize) {
1025 			if (!similar(ilineptr, plineptr, plinelen))
1026 				return false;
1027 		} else if (strnNE(ilineptr, plineptr, plinelen))
1028 			return false;
1029 		if (iline == input_lines) {
1030 			/*
1031 			 * We are looking at the last line of the file.
1032 			 * If the file has no eol, the patch line should
1033 			 * not have one either and vice-versa. Note that
1034 			 * plinelen > 0.
1035 			 */
1036 			if (last_line_missing_eol) {
1037 				if (plineptr[plinelen - 1] == '\n')
1038 					return false;
1039 			} else {
1040 				if (plineptr[plinelen - 1] != '\n')
1041 					return false;
1042 			}
1043 		}
1044 	}
1045 	return true;
1046 }
1047 
1048 /*
1049  * Do two lines match with canonicalized white space?
1050  */
1051 static bool
1052 similar(const char *a, const char *b, int len)
1053 {
1054 	while (len) {
1055 		if (isspace((unsigned char)*b)) {	/* whitespace (or \n) to match? */
1056 			if (!isspace((unsigned char)*a))	/* no corresponding whitespace? */
1057 				return false;
1058 			while (len && isspace((unsigned char)*b) && *b != '\n')
1059 				b++, len--;	/* skip pattern whitespace */
1060 			while (isspace((unsigned char)*a) && *a != '\n')
1061 				a++;	/* skip target whitespace */
1062 			if (*a == '\n' || *b == '\n')
1063 				return (*a == *b);	/* should end in sync */
1064 		} else if (*a++ != *b++)	/* match non-whitespace chars */
1065 			return false;
1066 		else
1067 			len--;	/* probably not necessary */
1068 	}
1069 	return true;		/* actually, this is not reached */
1070 	/* since there is always a \n */
1071 }
1072