patch.c revision 345878 
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 1.54 2014/12/13 10:31:07 tobias Exp $
27 * $FreeBSD: stable/11/usr.bin/patch/patch.c 345878 2019-04-04 17:21:30Z kevans $
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
49mode_t		filemode = 0644;
50
51char		*buf;			/* general purpose buffer */
52size_t		buf_size;		/* size of the general purpose buffer */
53
54bool		using_plan_a = true;	/* try to keep everything in memory */
55bool		out_of_mem = false;	/* ran out of memory in plan a */
56bool		nonempty_patchf_seen = false;	/* seen nonempty patch file? */
57
58#define MAXFILEC 2
59
60char		*filearg[MAXFILEC];
61bool		ok_to_create_file = false;
62char		*outname = NULL;
63char		*origprae = NULL;
64char		*TMPOUTNAME;
65char		*TMPINNAME;
66char		*TMPREJNAME;
67char		*TMPPATNAME;
68bool		toutkeep = false;
69bool		trejkeep = false;
70bool		warn_on_invalid_line;
71bool		last_line_missing_eol;
72
73#ifdef DEBUGGING
74int		debug = 0;
75#endif
76
77bool		force = false;
78bool		batch = false;
79bool		verbose = true;
80bool		reverse = false;
81bool		noreverse = false;
82bool		skip_rest_of_patch = false;
83int		strippath = 957;
84bool		canonicalize = false;
85bool		check_only = false;
86int		diff_type = 0;
87char		*revision = NULL;	/* prerequisite revision, if any */
88LINENUM		input_lines = 0;	/* how long is input file in lines */
89int		posix = 0;		/* strict POSIX mode? */
90
91static void	reinitialize_almost_everything(void);
92static void	get_some_switches(void);
93static LINENUM	locate_hunk(LINENUM);
94static void	abort_context_hunk(void);
95static void	rej_line(int, LINENUM);
96static void	abort_hunk(void);
97static void	apply_hunk(LINENUM);
98static void	init_output(const char *);
99static void	init_reject(const char *);
100static void	copy_till(LINENUM, bool);
101static bool	spew_output(void);
102static void	dump_line(LINENUM, bool);
103static bool	patch_match(LINENUM, LINENUM, LINENUM);
104static bool	similar(const char *, const char *, int);
105static void	usage(void);
106
107/* true if -E was specified on command line.  */
108static bool	remove_empty_files = false;
109
110/* true if -R was specified on command line.  */
111static bool	reverse_flag_specified = false;
112
113static bool	Vflag = false;
114
115/* buffer holding the name of the rejected patch file. */
116static char	rejname[PATH_MAX];
117
118/* how many input lines have been irretractibly output */
119static LINENUM	last_frozen_line = 0;
120
121static int	Argc;		/* guess */
122static char	**Argv;
123static int	Argc_last;	/* for restarting plan_b */
124static char	**Argv_last;
125
126static FILE	*ofp = NULL;	/* output file pointer */
127static FILE	*rejfp = NULL;	/* reject file pointer */
128
129static int	filec = 0;	/* how many file arguments? */
130static LINENUM	last_offset = 0;
131static LINENUM	maxfuzz = 2;
132
133/* patch using ifdef, ifndef, etc. */
134static bool		do_defines = false;
135/* #ifdef xyzzy */
136static char		if_defined[128];
137/* #ifndef xyzzy */
138static char		not_defined[128];
139/* #else */
140static const char	else_defined[] = "#else\n";
141/* #endif xyzzy */
142static char		end_defined[128];
143
144
145/* Apply a set of diffs as appropriate. */
146
147int
148main(int argc, char *argv[])
149{
150	int	error = 0, hunk, failed, i, fd;
151	bool	patch_seen, reverse_seen;
152	LINENUM	where = 0, newwhere, fuzz, mymaxfuzz;
153	const	char *tmpdir;
154	char	*v;
155
156	setvbuf(stdout, NULL, _IOLBF, 0);
157	setvbuf(stderr, NULL, _IOLBF, 0);
158	for (i = 0; i < MAXFILEC; i++)
159		filearg[i] = NULL;
160
161	buf_size = INITLINELEN;
162	buf = malloc((unsigned)(buf_size));
163	if (buf == NULL)
164		fatal("out of memory\n");
165
166	/* Cons up the names of the temporary files.  */
167	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
168		tmpdir = _PATH_TMP;
169	for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
170		;
171	i++;
172	if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
173		fatal("cannot allocate memory");
174	if ((fd = mkstemp(TMPOUTNAME)) < 0)
175		pfatal("can't create %s", TMPOUTNAME);
176	close(fd);
177
178	if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
179		fatal("cannot allocate memory");
180	if ((fd = mkstemp(TMPINNAME)) < 0)
181		pfatal("can't create %s", TMPINNAME);
182	close(fd);
183
184	if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
185		fatal("cannot allocate memory");
186	if ((fd = mkstemp(TMPREJNAME)) < 0)
187		pfatal("can't create %s", TMPREJNAME);
188	close(fd);
189
190	if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
191		fatal("cannot allocate memory");
192	if ((fd = mkstemp(TMPPATNAME)) < 0)
193		pfatal("can't create %s", TMPPATNAME);
194	close(fd);
195
196	v = getenv("SIMPLE_BACKUP_SUFFIX");
197	if (v)
198		simple_backup_suffix = v;
199	else
200		simple_backup_suffix = ORIGEXT;
201
202	/* parse switches */
203	Argc = argc;
204	Argv = argv;
205	get_some_switches();
206
207	if (!Vflag) {
208		if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
209			v = getenv("VERSION_CONTROL");
210		if (v != NULL || !posix)
211			backup_type = get_version(v);	/* OK to pass NULL. */
212	}
213
214	/* make sure we clean up /tmp in case of disaster */
215	set_signals(0);
216
217	patch_seen = false;
218	for (open_patch_file(filearg[1]); there_is_another_patch();
219	    reinitialize_almost_everything()) {
220		/* for each patch in patch file */
221
222		patch_seen = true;
223
224		warn_on_invalid_line = true;
225
226		if (outname == NULL)
227			outname = xstrdup(filearg[0]);
228
229		/* for ed script just up and do it and exit */
230		if (diff_type == ED_DIFF) {
231			do_ed_script();
232			continue;
233		}
234		/* initialize the patched file */
235		if (!skip_rest_of_patch)
236			init_output(TMPOUTNAME);
237
238		/* initialize reject file */
239		init_reject(TMPREJNAME);
240
241		/* find out where all the lines are */
242		if (!skip_rest_of_patch)
243			scan_input(filearg[0]);
244
245		/*
246		 * from here on, open no standard i/o files, because
247		 * malloc might misfire and we can't catch it easily
248		 */
249
250		/* apply each hunk of patch */
251		hunk = 0;
252		failed = 0;
253		reverse_seen = false;
254		out_of_mem = false;
255		while (another_hunk()) {
256			hunk++;
257			fuzz = 0;
258			mymaxfuzz = pch_context();
259			if (maxfuzz < mymaxfuzz)
260				mymaxfuzz = maxfuzz;
261			if (!skip_rest_of_patch) {
262				do {
263					where = locate_hunk(fuzz);
264					if (hunk == 1 && where == 0 && !force && !reverse_seen) {
265						/* dwim for reversed patch? */
266						if (!pch_swap()) {
267							if (fuzz == 0)
268								say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
269							continue;
270						}
271						reverse = !reverse;
272						/* try again */
273						where = locate_hunk(fuzz);
274						if (where == 0) {
275							/* didn't find it swapped */
276							if (!pch_swap())
277								/* put it back to normal */
278								fatal("lost hunk on alloc error!\n");
279							reverse = !reverse;
280						} else if (noreverse) {
281							if (!pch_swap())
282								/* put it back to normal */
283								fatal("lost hunk on alloc error!\n");
284							reverse = !reverse;
285							say("Ignoring previously applied (or reversed) patch.\n");
286							skip_rest_of_patch = true;
287						} else if (batch) {
288							if (verbose)
289								say("%seversed (or previously applied) patch detected!  %s -R.",
290								    reverse ? "R" : "Unr",
291								    reverse ? "Assuming" : "Ignoring");
292						} else {
293							ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
294							    reverse ? "R" : "Unr",
295							    reverse ? "Assume" : "Ignore");
296							if (*buf == 'n') {
297								ask("Apply anyway? [n] ");
298								if (*buf != 'y')
299									skip_rest_of_patch = true;
300								else
301									reverse_seen = true;
302								where = 0;
303								reverse = !reverse;
304								if (!pch_swap())
305									/* put it back to normal */
306									fatal("lost hunk on alloc error!\n");
307							}
308						}
309					}
310				} while (!skip_rest_of_patch && where == 0 &&
311				    ++fuzz <= mymaxfuzz);
312
313				if (skip_rest_of_patch) {	/* just got decided */
314					if (ferror(ofp) || fclose(ofp)) {
315						say("Error writing %s\n",
316						    TMPOUTNAME);
317						error = 1;
318					}
319					ofp = NULL;
320				}
321			}
322			newwhere = pch_newfirst() + last_offset;
323			if (skip_rest_of_patch) {
324				abort_hunk();
325				failed++;
326				if (verbose)
327					say("Hunk #%d ignored at %ld.\n",
328					    hunk, newwhere);
329			} else if (where == 0) {
330				abort_hunk();
331				failed++;
332				if (verbose)
333					say("Hunk #%d failed at %ld.\n",
334					    hunk, newwhere);
335			} else {
336				apply_hunk(where);
337				if (verbose) {
338					say("Hunk #%d succeeded at %ld",
339					    hunk, newwhere);
340					if (fuzz != 0)
341						say(" with fuzz %ld", fuzz);
342					if (last_offset)
343						say(" (offset %ld line%s)",
344						    last_offset,
345						    last_offset == 1L ? "" : "s");
346					say(".\n");
347				}
348			}
349		}
350
351		if (out_of_mem && using_plan_a) {
352			Argc = Argc_last;
353			Argv = Argv_last;
354			say("\n\nRan out of memory using Plan A--trying again...\n\n");
355			if (ofp)
356				fclose(ofp);
357			ofp = NULL;
358			if (rejfp)
359				fclose(rejfp);
360			rejfp = NULL;
361			continue;
362		}
363		if (hunk == 0)
364			fatal("Internal error: hunk should not be 0\n");
365
366		/* finish spewing out the new file */
367		if (!skip_rest_of_patch && !spew_output()) {
368			say("Can't write %s\n", TMPOUTNAME);
369			error = 1;
370		}
371
372		/* and put the output where desired */
373		ignore_signals();
374		if (!skip_rest_of_patch) {
375			struct stat	statbuf;
376			char	*realout = outname;
377
378			if (!check_only) {
379				if (move_file(TMPOUTNAME, outname) < 0) {
380					toutkeep = true;
381					realout = TMPOUTNAME;
382					chmod(TMPOUTNAME, filemode);
383				} else
384					chmod(outname, filemode);
385
386				if (remove_empty_files &&
387				    stat(realout, &statbuf) == 0 &&
388				    statbuf.st_size == 0) {
389					if (verbose)
390						say("Removing %s (empty after patching).\n",
391						    realout);
392					unlink(realout);
393				}
394			}
395		}
396		if (ferror(rejfp) || fclose(rejfp)) {
397			say("Error writing %s\n", rejname);
398			error = 1;
399		}
400		rejfp = NULL;
401		if (failed) {
402			error = 1;
403			if (*rejname == '\0') {
404				if (strlcpy(rejname, outname,
405				    sizeof(rejname)) >= sizeof(rejname))
406					fatal("filename %s is too long\n", outname);
407				if (strlcat(rejname, REJEXT,
408				    sizeof(rejname)) >= sizeof(rejname))
409					fatal("filename %s is too long\n", outname);
410			}
411			if (!check_only)
412				say("%d out of %d hunks %s--saving rejects to %s\n",
413				    failed, hunk, skip_rest_of_patch ? "ignored" : "failed", rejname);
414			else
415				say("%d out of %d hunks %s while patching %s\n",
416				    failed, hunk, skip_rest_of_patch ? "ignored" : "failed", filearg[0]);
417			if (!check_only && move_file(TMPREJNAME, rejname) < 0)
418				trejkeep = true;
419		}
420		set_signals(1);
421	}
422
423	if (!patch_seen && nonempty_patchf_seen)
424		error = 2;
425
426	my_exit(error);
427	/* NOTREACHED */
428}
429
430/* Prepare to find the next patch to do in the patch file. */
431
432static void
433reinitialize_almost_everything(void)
434{
435	re_patch();
436	re_input();
437
438	input_lines = 0;
439	last_frozen_line = 0;
440
441	filec = 0;
442	if (!out_of_mem) {
443		free(filearg[0]);
444		filearg[0] = NULL;
445	}
446
447	free(outname);
448	outname = NULL;
449
450	last_offset = 0;
451	diff_type = 0;
452
453	free(revision);
454	revision = NULL;
455
456	reverse = reverse_flag_specified;
457	skip_rest_of_patch = false;
458
459	get_some_switches();
460}
461
462/* Process switches and filenames. */
463
464static void
465get_some_switches(void)
466{
467	const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
468	static struct option longopts[] = {
469		{"backup",		no_argument,		0,	'b'},
470		{"batch",		no_argument,		0,	't'},
471		{"check",		no_argument,		0,	'C'},
472		{"context",		no_argument,		0,	'c'},
473		{"debug",		required_argument,	0,	'x'},
474		{"directory",		required_argument,	0,	'd'},
475		{"dry-run",		no_argument,		0,	'C'},
476		{"ed",			no_argument,		0,	'e'},
477		{"force",		no_argument,		0,	'f'},
478		{"forward",		no_argument,		0,	'N'},
479		{"fuzz",		required_argument,	0,	'F'},
480		{"ifdef",		required_argument,	0,	'D'},
481		{"input",		required_argument,	0,	'i'},
482		{"ignore-whitespace",	no_argument,		0,	'l'},
483		{"normal",		no_argument,		0,	'n'},
484		{"output",		required_argument,	0,	'o'},
485		{"prefix",		required_argument,	0,	'B'},
486		{"quiet",		no_argument,		0,	's'},
487		{"reject-file",		required_argument,	0,	'r'},
488		{"remove-empty-files",	no_argument,		0,	'E'},
489		{"reverse",		no_argument,		0,	'R'},
490		{"silent",		no_argument,		0,	's'},
491		{"strip",		required_argument,	0,	'p'},
492		{"suffix",		required_argument,	0,	'z'},
493		{"unified",		no_argument,		0,	'u'},
494		{"version",		no_argument,		0,	'v'},
495		{"version-control",	required_argument,	0,	'V'},
496		{"posix",		no_argument,		&posix,	1},
497		{NULL,			0,			0,	0}
498	};
499	int ch;
500
501	rejname[0] = '\0';
502	Argc_last = Argc;
503	Argv_last = Argv;
504	if (!Argc)
505		return;
506	optreset = optind = 1;
507	while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
508		switch (ch) {
509		case 'b':
510			if (backup_type == none)
511				backup_type = numbered_existing;
512			if (optarg == NULL)
513				break;
514			if (verbose)
515				say("Warning, the ``-b suffix'' option has been"
516				    " obsoleted by the -z option.\n");
517			/* FALLTHROUGH */
518		case 'z':
519			/* must directly follow 'b' case for backwards compat */
520			simple_backup_suffix = xstrdup(optarg);
521			break;
522		case 'B':
523			origprae = xstrdup(optarg);
524			break;
525		case 'c':
526			diff_type = CONTEXT_DIFF;
527			break;
528		case 'C':
529			check_only = true;
530			break;
531		case 'd':
532			if (chdir(optarg) < 0)
533				pfatal("can't cd to %s", optarg);
534			break;
535		case 'D':
536			do_defines = true;
537			if (!isalpha((unsigned char)*optarg) && *optarg != '_')
538				fatal("argument to -D is not an identifier\n");
539			snprintf(if_defined, sizeof if_defined,
540			    "#ifdef %s\n", optarg);
541			snprintf(not_defined, sizeof not_defined,
542			    "#ifndef %s\n", optarg);
543			snprintf(end_defined, sizeof end_defined,
544			    "#endif /* %s */\n", optarg);
545			break;
546		case 'e':
547			diff_type = ED_DIFF;
548			break;
549		case 'E':
550			remove_empty_files = true;
551			break;
552		case 'f':
553			force = true;
554			break;
555		case 'F':
556			maxfuzz = atoi(optarg);
557			break;
558		case 'i':
559			if (++filec == MAXFILEC)
560				fatal("too many file arguments\n");
561			filearg[filec] = xstrdup(optarg);
562			break;
563		case 'l':
564			canonicalize = true;
565			break;
566		case 'n':
567			diff_type = NORMAL_DIFF;
568			break;
569		case 'N':
570			noreverse = true;
571			break;
572		case 'o':
573			outname = xstrdup(optarg);
574			break;
575		case 'p':
576			strippath = atoi(optarg);
577			break;
578		case 'r':
579			if (strlcpy(rejname, optarg,
580			    sizeof(rejname)) >= sizeof(rejname))
581				fatal("argument for -r is too long\n");
582			break;
583		case 'R':
584			reverse = true;
585			reverse_flag_specified = true;
586			break;
587		case 's':
588			verbose = false;
589			break;
590		case 't':
591			batch = true;
592			break;
593		case 'u':
594			diff_type = UNI_DIFF;
595			break;
596		case 'v':
597			version();
598			break;
599		case 'V':
600			backup_type = get_version(optarg);
601			Vflag = true;
602			break;
603#ifdef DEBUGGING
604		case 'x':
605			debug = atoi(optarg);
606			break;
607#endif
608		default:
609			if (ch != '\0')
610				usage();
611			break;
612		}
613	}
614	Argc -= optind;
615	Argv += optind;
616
617	if (Argc > 0) {
618		filearg[0] = xstrdup(*Argv++);
619		Argc--;
620		while (Argc > 0) {
621			if (++filec == MAXFILEC)
622				fatal("too many file arguments\n");
623			filearg[filec] = xstrdup(*Argv++);
624			Argc--;
625		}
626	}
627
628	if (getenv("POSIXLY_CORRECT") != NULL)
629		posix = 1;
630}
631
632static void
633usage(void)
634{
635	fprintf(stderr,
636"usage: patch [-bCcEeflNnRstuv] [-B backup-prefix] [-D symbol] [-d directory]\n"
637"             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
638"             [-r rej-name] [-V t | nil | never | none] [-x number]\n"
639"             [-z backup-ext] [--posix] [origfile [patchfile]]\n"
640"       patch <patchfile\n");
641	my_exit(EXIT_FAILURE);
642}
643
644/*
645 * Attempt to find the right place to apply this hunk of patch.
646 */
647static LINENUM
648locate_hunk(LINENUM fuzz)
649{
650	LINENUM	first_guess = pch_first() + last_offset;
651	LINENUM	offset;
652	LINENUM	pat_lines = pch_ptrn_lines();
653	LINENUM	max_pos_offset = input_lines - first_guess - pat_lines + 1;
654	LINENUM	max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
655
656	if (pat_lines == 0) {		/* null range matches always */
657		if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
658		    || diff_type == NEW_CONTEXT_DIFF
659		    || diff_type == UNI_DIFF)) {
660			say("Empty context always matches.\n");
661		}
662		return (first_guess);
663	}
664	if (max_neg_offset >= first_guess)	/* do not try lines < 0 */
665		max_neg_offset = first_guess - 1;
666	if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
667		return first_guess;
668	for (offset = 1; ; offset++) {
669		bool	check_after = (offset <= max_pos_offset);
670		bool	check_before = (offset <= max_neg_offset);
671
672		if (check_after && 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 && patch_match(first_guess, -offset, fuzz)) {
681#ifdef DEBUGGING
682			if (debug & 1)
683				say("Offset changing from %ld to %ld\n",
684				    last_offset, -offset);
685#endif
686			last_offset = -offset;
687			return first_guess - offset;
688		} else if (!check_before && !check_after)
689			return 0;
690	}
691}
692
693/* We did not find the pattern, dump out the hunk so they can handle it. */
694
695static void
696abort_context_hunk(void)
697{
698	LINENUM	i;
699	const LINENUM	pat_end = pch_end();
700	/*
701	 * add in last_offset to guess the same as the previous successful
702	 * hunk
703	 */
704	const LINENUM	oldfirst = pch_first() + last_offset;
705	const LINENUM	newfirst = pch_newfirst() + last_offset;
706	const LINENUM	oldlast = oldfirst + pch_ptrn_lines() - 1;
707	const LINENUM	newlast = newfirst + pch_repl_lines() - 1;
708	const char	*stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
709	const char	*minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
710
711	fprintf(rejfp, "***************\n");
712	for (i = 0; i <= pat_end; i++) {
713		switch (pch_char(i)) {
714		case '*':
715			if (oldlast < oldfirst)
716				fprintf(rejfp, "*** 0%s\n", stars);
717			else if (oldlast == oldfirst)
718				fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
719			else
720				fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
721				    oldlast, stars);
722			break;
723		case '=':
724			if (newlast < newfirst)
725				fprintf(rejfp, "--- 0%s\n", minuses);
726			else if (newlast == newfirst)
727				fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
728			else
729				fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
730				    newlast, minuses);
731			break;
732		case '\n':
733			fprintf(rejfp, "%s", pfetch(i));
734			break;
735		case ' ':
736		case '-':
737		case '+':
738		case '!':
739			fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
740			break;
741		default:
742			fatal("fatal internal error in abort_context_hunk\n");
743		}
744	}
745}
746
747static void
748rej_line(int ch, LINENUM i)
749{
750	size_t len;
751	const char *line = pfetch(i);
752
753	len = strlen(line);
754
755	fprintf(rejfp, "%c%s", ch, line);
756	if (len == 0 || line[len - 1] != '\n') {
757		if (len >= USHRT_MAX)
758			fprintf(rejfp, "\n\\ Line too long\n");
759		else
760			fprintf(rejfp, "\n\\ No newline at end of line\n");
761	}
762}
763
764static void
765abort_hunk(void)
766{
767	LINENUM		i, j, split;
768	int		ch1, ch2;
769	const LINENUM	pat_end = pch_end();
770	const LINENUM	oldfirst = pch_first() + last_offset;
771	const LINENUM	newfirst = pch_newfirst() + last_offset;
772
773	if (diff_type != UNI_DIFF) {
774		abort_context_hunk();
775		return;
776	}
777	split = -1;
778	for (i = 0; i <= pat_end; i++) {
779		if (pch_char(i) == '=') {
780			split = i;
781			break;
782		}
783	}
784	if (split == -1) {
785		fprintf(rejfp, "malformed hunk: no split found\n");
786		return;
787	}
788	i = 0;
789	j = split + 1;
790	fprintf(rejfp, "@@ -%ld,%ld +%ld,%ld @@\n",
791	    pch_ptrn_lines() ? oldfirst : 0,
792	    pch_ptrn_lines(), newfirst, pch_repl_lines());
793	while (i < split || j <= pat_end) {
794		ch1 = i < split ? pch_char(i) : -1;
795		ch2 = j <= pat_end ? pch_char(j) : -1;
796		if (ch1 == '-') {
797			rej_line('-', i);
798			i++;
799		} else if (ch1 == ' ' && ch2 == ' ') {
800			rej_line(' ', i);
801			i++;
802			j++;
803		} else if (ch1 == '!' && ch2 == '!') {
804			while (i < split && ch1 == '!') {
805				rej_line('-', i);
806				i++;
807				ch1 = i < split ? pch_char(i) : -1;
808			}
809			while (j <= pat_end && ch2 == '!') {
810				rej_line('+', j);
811				j++;
812				ch2 = j <= pat_end ? pch_char(j) : -1;
813			}
814		} else if (ch1 == '*') {
815			i++;
816		} else if (ch2 == '+' || ch2 == ' ') {
817			rej_line(ch2, j);
818			j++;
819		} else {
820			fprintf(rejfp, "internal error on (%ld %ld %ld)\n",
821			    i, split, j);
822			rej_line(ch1, i);
823			rej_line(ch2, j);
824			return;
825		}
826	}
827}
828
829/* We found where to apply it (we hope), so do it. */
830
831static void
832apply_hunk(LINENUM where)
833{
834	LINENUM		old = 1;
835	const LINENUM	lastline = pch_ptrn_lines();
836	LINENUM		new = lastline + 1;
837#define OUTSIDE 0
838#define IN_IFNDEF 1
839#define IN_IFDEF 2
840#define IN_ELSE 3
841	int		def_state = OUTSIDE;
842	const LINENUM	pat_end = pch_end();
843
844	where--;
845	while (pch_char(new) == '=' || pch_char(new) == '\n')
846		new++;
847
848	while (old <= lastline) {
849		if (pch_char(old) == '-') {
850			copy_till(where + old - 1, false);
851			if (do_defines) {
852				if (def_state == OUTSIDE) {
853					fputs(not_defined, ofp);
854					def_state = IN_IFNDEF;
855				} else if (def_state == IN_IFDEF) {
856					fputs(else_defined, ofp);
857					def_state = IN_ELSE;
858				}
859				fputs(pfetch(old), ofp);
860			}
861			last_frozen_line++;
862			old++;
863		} else if (new > pat_end) {
864			break;
865		} else if (pch_char(new) == '+') {
866			copy_till(where + old - 1, false);
867			if (do_defines) {
868				if (def_state == IN_IFNDEF) {
869					fputs(else_defined, ofp);
870					def_state = IN_ELSE;
871				} else if (def_state == OUTSIDE) {
872					fputs(if_defined, ofp);
873					def_state = IN_IFDEF;
874				}
875			}
876			fputs(pfetch(new), ofp);
877			new++;
878		} else if (pch_char(new) != pch_char(old)) {
879			say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
880			    pch_hunk_beg() + old,
881			    pch_hunk_beg() + new);
882#ifdef DEBUGGING
883			say("oldchar = '%c', newchar = '%c'\n",
884			    pch_char(old), pch_char(new));
885#endif
886			my_exit(2);
887		} else if (pch_char(new) == '!') {
888			copy_till(where + old - 1, false);
889			if (do_defines) {
890				fputs(not_defined, ofp);
891				def_state = IN_IFNDEF;
892			}
893			while (pch_char(old) == '!') {
894				if (do_defines) {
895					fputs(pfetch(old), ofp);
896				}
897				last_frozen_line++;
898				old++;
899			}
900			if (do_defines) {
901				fputs(else_defined, ofp);
902				def_state = IN_ELSE;
903			}
904			while (pch_char(new) == '!') {
905				fputs(pfetch(new), ofp);
906				new++;
907			}
908		} else {
909			if (pch_char(new) != ' ')
910				fatal("Internal error: expected ' '\n");
911			old++;
912			new++;
913			if (do_defines && def_state != OUTSIDE) {
914				fputs(end_defined, ofp);
915				def_state = OUTSIDE;
916			}
917		}
918	}
919	if (new <= pat_end && pch_char(new) == '+') {
920		copy_till(where + old - 1, false);
921		if (do_defines) {
922			if (def_state == OUTSIDE) {
923				fputs(if_defined, ofp);
924				def_state = IN_IFDEF;
925			} else if (def_state == IN_IFNDEF) {
926				fputs(else_defined, ofp);
927				def_state = IN_ELSE;
928			}
929		}
930		while (new <= pat_end && pch_char(new) == '+') {
931			fputs(pfetch(new), ofp);
932			new++;
933		}
934	}
935	if (do_defines && def_state != OUTSIDE) {
936		fputs(end_defined, ofp);
937	}
938}
939
940/*
941 * Open the new file.
942 */
943static void
944init_output(const char *name)
945{
946	ofp = fopen(name, "w");
947	if (ofp == NULL)
948		pfatal("can't create %s", name);
949}
950
951/*
952 * Open a file to put hunks we can't locate.
953 */
954static void
955init_reject(const char *name)
956{
957	rejfp = fopen(name, "w");
958	if (rejfp == NULL)
959		pfatal("can't create %s", name);
960}
961
962/*
963 * Copy input file to output, up to wherever hunk is to be applied.
964 * If endoffile is true, treat the last line specially since it may
965 * lack a newline.
966 */
967static void
968copy_till(LINENUM lastline, bool endoffile)
969{
970	if (last_frozen_line > lastline)
971		fatal("misordered hunks! output would be garbled\n");
972	while (last_frozen_line < lastline) {
973		if (++last_frozen_line == lastline && endoffile)
974			dump_line(last_frozen_line, !last_line_missing_eol);
975		else
976			dump_line(last_frozen_line, true);
977	}
978}
979
980/*
981 * Finish copying the input file to the output file.
982 */
983static bool
984spew_output(void)
985{
986	int rv;
987
988#ifdef DEBUGGING
989	if (debug & 256)
990		say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
991#endif
992	if (input_lines)
993		copy_till(input_lines, true);	/* dump remainder of file */
994	rv = ferror(ofp) == 0 && fclose(ofp) == 0;
995	ofp = NULL;
996	return rv;
997}
998
999/*
1000 * Copy one line from input to output.
1001 */
1002static void
1003dump_line(LINENUM line, bool write_newline)
1004{
1005	char	*s;
1006
1007	s = ifetch(line, 0);
1008	if (s == NULL)
1009		return;
1010	/* Note: string is not NUL terminated. */
1011	for (; *s != '\n'; s++)
1012		putc(*s, ofp);
1013	if (write_newline)
1014		putc('\n', ofp);
1015}
1016
1017/*
1018 * Does the patch pattern match at line base+offset?
1019 */
1020static bool
1021patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
1022{
1023	LINENUM		pline = 1 + fuzz;
1024	LINENUM		iline;
1025	LINENUM		pat_lines = pch_ptrn_lines() - fuzz;
1026	const char	*ilineptr;
1027	const char	*plineptr;
1028	unsigned short	plinelen;
1029
1030	/* Patch does not match if we don't have any more context to use */
1031	if (pline > pat_lines)
1032		return false;
1033	for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
1034		ilineptr = ifetch(iline, offset >= 0);
1035		if (ilineptr == NULL)
1036			return false;
1037		plineptr = pfetch(pline);
1038		plinelen = pch_line_len(pline);
1039		if (canonicalize) {
1040			if (!similar(ilineptr, plineptr, plinelen))
1041				return false;
1042		} else if (strnNE(ilineptr, plineptr, plinelen))
1043			return false;
1044		if (iline == input_lines) {
1045			/*
1046			 * We are looking at the last line of the file.
1047			 * If the file has no eol, the patch line should
1048			 * not have one either and vice-versa. Note that
1049			 * plinelen > 0.
1050			 */
1051			if (last_line_missing_eol) {
1052				if (plineptr[plinelen - 1] == '\n')
1053					return false;
1054			} else {
1055				if (plineptr[plinelen - 1] != '\n')
1056					return false;
1057			}
1058		}
1059	}
1060	return true;
1061}
1062
1063/*
1064 * Do two lines match with canonicalized white space?
1065 */
1066static bool
1067similar(const char *a, const char *b, int len)
1068{
1069	while (len) {
1070		if (isspace((unsigned char)*b)) {	/* whitespace (or \n) to match? */
1071			if (!isspace((unsigned char)*a))	/* no corresponding whitespace? */
1072				return false;
1073			while (len && isspace((unsigned char)*b) && *b != '\n')
1074				b++, len--;	/* skip pattern whitespace */
1075			while (isspace((unsigned char)*a) && *a != '\n')
1076				a++;	/* skip target whitespace */
1077			if (*a == '\n' || *b == '\n')
1078				return (*a == *b);	/* should end in sync */
1079		} else if (*a++ != *b++)	/* match non-whitespace chars */
1080			return false;
1081		else
1082			len--;	/* probably not necessary */
1083	}
1084	return true;		/* actually, this is not reached */
1085	/* since there is always a \n */
1086}
1087