pch.c revision 293290
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: pch.c,v 1.43 2014/11/18 17:03:35 tobias Exp $
27 * $FreeBSD: stable/10/usr.bin/patch/pch.c 293290 2016-01-07 00:40:51Z bdrewery $
28 */
29
30#include <sys/types.h>
31#include <sys/stat.h>
32
33#include <ctype.h>
34#include <libgen.h>
35#include <limits.h>
36#include <stdint.h>
37#include <stdio.h>
38#include <stdlib.h>
39#include <string.h>
40#include <unistd.h>
41
42#include "common.h"
43#include "util.h"
44#include "pch.h"
45#include "pathnames.h"
46
47/* Patch (diff listing) abstract type. */
48
49static off_t	p_filesize;	/* size of the patch file */
50static LINENUM	p_first;	/* 1st line number */
51static LINENUM	p_newfirst;	/* 1st line number of replacement */
52static LINENUM	p_ptrn_lines;	/* # lines in pattern */
53static LINENUM	p_repl_lines;	/* # lines in replacement text */
54static LINENUM	p_end = -1;	/* last line in hunk */
55static LINENUM	p_max;		/* max allowed value of p_end */
56static LINENUM	p_context = 3;	/* # of context lines */
57static LINENUM	p_input_line = 0;	/* current line # from patch file */
58static char	**p_line = NULL;/* the text of the hunk */
59static unsigned short	*p_len = NULL; /* length of each line */
60static char	*p_char = NULL;	/* +, -, and ! */
61static int	hunkmax = INITHUNKMAX;	/* size of above arrays to begin with */
62static int	p_indent;	/* indent to patch */
63static off_t	p_base;		/* where to intuit this time */
64static LINENUM	p_bline;	/* line # of p_base */
65static off_t	p_start;	/* where intuit found a patch */
66static LINENUM	p_sline;	/* and the line number for it */
67static LINENUM	p_hunk_beg;	/* line number of current hunk */
68static LINENUM	p_efake = -1;	/* end of faked up lines--don't free */
69static LINENUM	p_bfake = -1;	/* beg of faked up lines */
70static FILE	*pfp = NULL;	/* patch file pointer */
71static char	*bestguess = NULL;	/* guess at correct filename */
72
73static void	grow_hunkmax(void);
74static int	intuit_diff_type(void);
75static void	next_intuit_at(off_t, LINENUM);
76static void	skip_to(off_t, LINENUM);
77static size_t	pgets(bool _do_indent);
78static char	*best_name(const struct file_name *, bool);
79static char	*posix_name(const struct file_name *, bool);
80static size_t	num_components(const char *);
81static LINENUM	strtolinenum(char *, char **);
82
83/*
84 * Prepare to look for the next patch in the patch file.
85 */
86void
87re_patch(void)
88{
89	p_first = 0;
90	p_newfirst = 0;
91	p_ptrn_lines = 0;
92	p_repl_lines = 0;
93	p_end = (LINENUM) - 1;
94	p_max = 0;
95	p_indent = 0;
96}
97
98/*
99 * Open the patch file at the beginning of time.
100 */
101void
102open_patch_file(const char *filename)
103{
104	struct stat filestat;
105	int nr, nw;
106
107	if (filename == NULL || *filename == '\0' || strEQ(filename, "-")) {
108		pfp = fopen(TMPPATNAME, "w");
109		if (pfp == NULL)
110			pfatal("can't create %s", TMPPATNAME);
111		while ((nr = fread(buf, 1, buf_size, stdin)) > 0) {
112			nw = fwrite(buf, 1, nr, pfp);
113			if (nr != nw)
114				pfatal("write error to %s", TMPPATNAME);
115		}
116		if (ferror(pfp) || fclose(pfp))
117			pfatal("can't write %s", TMPPATNAME);
118		filename = TMPPATNAME;
119	}
120	pfp = fopen(filename, "r");
121	if (pfp == NULL)
122		pfatal("patch file %s not found", filename);
123	if (fstat(fileno(pfp), &filestat))
124		pfatal("can't stat %s", filename);
125	p_filesize = filestat.st_size;
126	next_intuit_at(0, 1L);	/* start at the beginning */
127	set_hunkmax();
128}
129
130/*
131 * Make sure our dynamically realloced tables are malloced to begin with.
132 */
133void
134set_hunkmax(void)
135{
136	if (p_line == NULL)
137		p_line = malloc(hunkmax * sizeof(char *));
138	if (p_len == NULL)
139		p_len = malloc(hunkmax * sizeof(unsigned short));
140	if (p_char == NULL)
141		p_char = malloc(hunkmax * sizeof(char));
142}
143
144/*
145 * Enlarge the arrays containing the current hunk of patch.
146 */
147static void
148grow_hunkmax(void)
149{
150	int new_hunkmax = hunkmax * 2;
151
152	if (p_line == NULL || p_len == NULL || p_char == NULL)
153		fatal("Internal memory allocation error\n");
154
155	p_line = reallocf(p_line, new_hunkmax * sizeof(char *));
156	p_len = reallocf(p_len, new_hunkmax * sizeof(unsigned short));
157	p_char = reallocf(p_char, new_hunkmax * sizeof(char));
158
159	if (p_line != NULL && p_len != NULL && p_char != NULL) {
160		hunkmax = new_hunkmax;
161		return;
162	}
163
164	if (!using_plan_a)
165		fatal("out of memory\n");
166	out_of_mem = true;	/* whatever is null will be allocated again */
167				/* from within plan_a(), of all places */
168}
169
170/* True if the remainder of the patch file contains a diff of some sort. */
171
172bool
173there_is_another_patch(void)
174{
175	bool exists = false;
176
177	if (p_base != 0 && p_base >= p_filesize) {
178		if (verbose)
179			say("done\n");
180		return false;
181	}
182	if (verbose)
183		say("Hmm...");
184	diff_type = intuit_diff_type();
185	if (!diff_type) {
186		if (p_base != 0) {
187			if (verbose)
188				say("  Ignoring the trailing garbage.\ndone\n");
189		} else
190			say("  I can't seem to find a patch in there anywhere.\n");
191		return false;
192	}
193	if (verbose)
194		say("  %sooks like %s to me...\n",
195		    (p_base == 0 ? "L" : "The next patch l"),
196		    diff_type == UNI_DIFF ? "a unified diff" :
197		    diff_type == CONTEXT_DIFF ? "a context diff" :
198		diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
199		    diff_type == NORMAL_DIFF ? "a normal diff" :
200		    "an ed script");
201	if (p_indent && verbose)
202		say("(Patch is indented %d space%s.)\n", p_indent,
203		    p_indent == 1 ? "" : "s");
204	skip_to(p_start, p_sline);
205	while (filearg[0] == NULL) {
206		if (force || batch) {
207			say("No file to patch.  Skipping...\n");
208			filearg[0] = xstrdup(bestguess);
209			skip_rest_of_patch = true;
210			return true;
211		}
212		ask("File to patch: ");
213		if (*buf != '\n') {
214			free(bestguess);
215			bestguess = xstrdup(buf);
216			filearg[0] = fetchname(buf, &exists, 0);
217		}
218		if (!exists) {
219			ask("No file found--skip this patch? [n] ");
220			if (*buf != 'y')
221				continue;
222			if (verbose)
223				say("Skipping patch...\n");
224			free(filearg[0]);
225			filearg[0] = fetchname(bestguess, &exists, 0);
226			skip_rest_of_patch = true;
227			return true;
228		}
229	}
230	return true;
231}
232
233static void
234p4_fetchname(struct file_name *name, char *str)
235{
236	char *t, *h;
237
238	/* Skip leading whitespace. */
239	while (isspace((unsigned char)*str))
240		str++;
241
242	/* Remove the file revision number. */
243	for (t = str, h = NULL; *t != '\0' && !isspace((unsigned char)*t); t++)
244		if (*t == '#')
245			h = t;
246	if (h != NULL)
247		*h = '\0';
248
249	name->path = fetchname(str, &name->exists, strippath);
250}
251
252/* Determine what kind of diff is in the remaining part of the patch file. */
253
254static int
255intuit_diff_type(void)
256{
257	off_t	this_line = 0, previous_line;
258	off_t	first_command_line = -1;
259	LINENUM	fcl_line = -1;
260	bool	last_line_was_command = false, this_is_a_command = false;
261	bool	stars_last_line = false, stars_this_line = false;
262	char	*s, *t;
263	int	indent, retval;
264	struct file_name names[MAX_FILE];
265
266	memset(names, 0, sizeof(names));
267	ok_to_create_file = false;
268	fseeko(pfp, p_base, SEEK_SET);
269	p_input_line = p_bline - 1;
270	for (;;) {
271		previous_line = this_line;
272		last_line_was_command = this_is_a_command;
273		stars_last_line = stars_this_line;
274		this_line = ftello(pfp);
275		indent = 0;
276		p_input_line++;
277		if (pgets(false) == 0) {
278			if (first_command_line >= 0) {
279				/* nothing but deletes!? */
280				p_start = first_command_line;
281				p_sline = fcl_line;
282				retval = ED_DIFF;
283				goto scan_exit;
284			} else {
285				p_start = this_line;
286				p_sline = p_input_line;
287				retval = 0;
288				goto scan_exit;
289			}
290		}
291		for (s = buf; *s == ' ' || *s == '\t' || *s == 'X'; s++) {
292			if (*s == '\t')
293				indent += 8 - (indent % 8);
294			else
295				indent++;
296		}
297		for (t = s; isdigit((unsigned char)*t) || *t == ','; t++)
298			;
299		this_is_a_command = (isdigit((unsigned char)*s) &&
300		    (*t == 'd' || *t == 'c' || *t == 'a'));
301		if (first_command_line < 0 && this_is_a_command) {
302			first_command_line = this_line;
303			fcl_line = p_input_line;
304			p_indent = indent;	/* assume this for now */
305		}
306		if (!stars_last_line && strnEQ(s, "*** ", 4))
307			names[OLD_FILE].path = fetchname(s + 4,
308			    &names[OLD_FILE].exists, strippath);
309		else if (strnEQ(s, "--- ", 4))
310			names[NEW_FILE].path = fetchname(s + 4,
311			    &names[NEW_FILE].exists, strippath);
312		else if (strnEQ(s, "+++ ", 4))
313			/* pretend it is the old name */
314			names[OLD_FILE].path = fetchname(s + 4,
315			    &names[OLD_FILE].exists, strippath);
316		else if (strnEQ(s, "Index:", 6))
317			names[INDEX_FILE].path = fetchname(s + 6,
318			    &names[INDEX_FILE].exists, strippath);
319		else if (strnEQ(s, "Prereq:", 7)) {
320			for (t = s + 7; isspace((unsigned char)*t); t++)
321				;
322			revision = xstrdup(t);
323			for (t = revision;
324			     *t && !isspace((unsigned char)*t); t++)
325				;
326			*t = '\0';
327			if (*revision == '\0') {
328				free(revision);
329				revision = NULL;
330			}
331		} else if (strnEQ(s, "==== ", 5)) {
332			/* Perforce-style diffs. */
333			if ((t = strstr(s + 5, " - ")) != NULL)
334				p4_fetchname(&names[NEW_FILE], t + 3);
335			p4_fetchname(&names[OLD_FILE], s + 5);
336		}
337		if ((!diff_type || diff_type == ED_DIFF) &&
338		    first_command_line >= 0 &&
339		    strEQ(s, ".\n")) {
340			p_indent = indent;
341			p_start = first_command_line;
342			p_sline = fcl_line;
343			retval = ED_DIFF;
344			goto scan_exit;
345		}
346		if ((!diff_type || diff_type == UNI_DIFF) && strnEQ(s, "@@ -", 4)) {
347			if (strnEQ(s + 4, "0,0", 3))
348				ok_to_create_file = true;
349			p_indent = indent;
350			p_start = this_line;
351			p_sline = p_input_line;
352			retval = UNI_DIFF;
353			goto scan_exit;
354		}
355		stars_this_line = strnEQ(s, "********", 8);
356		if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
357		    strnEQ(s, "*** ", 4)) {
358			if (strtolinenum(s + 4, &s) == 0)
359				ok_to_create_file = true;
360			/*
361			 * If this is a new context diff the character just
362			 * at the end of the line is a '*'.
363			 */
364			while (*s && *s != '\n')
365				s++;
366			p_indent = indent;
367			p_start = previous_line;
368			p_sline = p_input_line - 1;
369			retval = (*(s - 1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
370			goto scan_exit;
371		}
372		if ((!diff_type || diff_type == NORMAL_DIFF) &&
373		    last_line_was_command &&
374		    (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2))) {
375			p_start = previous_line;
376			p_sline = p_input_line - 1;
377			p_indent = indent;
378			retval = NORMAL_DIFF;
379			goto scan_exit;
380		}
381	}
382scan_exit:
383	if (retval == UNI_DIFF) {
384		/* unswap old and new */
385		struct file_name tmp = names[OLD_FILE];
386		names[OLD_FILE] = names[NEW_FILE];
387		names[NEW_FILE] = tmp;
388	}
389	if (filearg[0] == NULL) {
390		if (posix)
391			filearg[0] = posix_name(names, ok_to_create_file);
392		else {
393			/* Ignore the Index: name for context diffs, like GNU */
394			if (names[OLD_FILE].path != NULL ||
395			    names[NEW_FILE].path != NULL) {
396				free(names[INDEX_FILE].path);
397				names[INDEX_FILE].path = NULL;
398			}
399			filearg[0] = best_name(names, ok_to_create_file);
400		}
401	}
402
403	free(bestguess);
404	bestguess = NULL;
405	if (filearg[0] != NULL)
406		bestguess = xstrdup(filearg[0]);
407	else if (!ok_to_create_file) {
408		/*
409		 * We don't want to create a new file but we need a
410		 * filename to set bestguess.  Avoid setting filearg[0]
411		 * so the file is not created automatically.
412		 */
413		if (posix)
414			bestguess = posix_name(names, true);
415		else
416			bestguess = best_name(names, true);
417	}
418	free(names[OLD_FILE].path);
419	free(names[NEW_FILE].path);
420	free(names[INDEX_FILE].path);
421	return retval;
422}
423
424/*
425 * Remember where this patch ends so we know where to start up again.
426 */
427static void
428next_intuit_at(off_t file_pos, LINENUM file_line)
429{
430	p_base = file_pos;
431	p_bline = file_line;
432}
433
434/*
435 * Basically a verbose fseeko() to the actual diff listing.
436 */
437static void
438skip_to(off_t file_pos, LINENUM file_line)
439{
440	size_t	len;
441
442	if (p_base > file_pos)
443		fatal("Internal error: seek %lld>%lld\n",
444		   (long long)p_base, (long long)file_pos);
445	if (verbose && p_base < file_pos) {
446		fseeko(pfp, p_base, SEEK_SET);
447		say("The text leading up to this was:\n--------------------------\n");
448		while (ftello(pfp) < file_pos) {
449			len = pgets(false);
450			if (len == 0)
451				fatal("Unexpected end of file\n");
452			say("|%s", buf);
453		}
454		say("--------------------------\n");
455	} else
456		fseeko(pfp, file_pos, SEEK_SET);
457	p_input_line = file_line - 1;
458}
459
460/* Make this a function for better debugging.  */
461static void
462malformed(void)
463{
464	fatal("malformed patch at line %ld: %s", p_input_line, buf);
465	/* about as informative as "Syntax error" in C */
466}
467
468/*
469 * True if the line has been discarded (i.e. it is a line saying
470 *  "\ No newline at end of file".)
471 */
472static bool
473remove_special_line(void)
474{
475	int	c;
476
477	c = fgetc(pfp);
478	if (c == '\\') {
479		do {
480			c = fgetc(pfp);
481		} while (c != EOF && c != '\n');
482
483		return true;
484	}
485	if (c != EOF)
486		fseeko(pfp, -1, SEEK_CUR);
487
488	return false;
489}
490
491/*
492 * True if there is more of the current diff listing to process.
493 */
494bool
495another_hunk(void)
496{
497	off_t	line_beginning;			/* file pos of the current line */
498	LINENUM	repl_beginning;			/* index of --- line */
499	LINENUM	fillcnt;			/* #lines of missing ptrn or repl */
500	LINENUM	fillsrc;			/* index of first line to copy */
501	LINENUM	filldst;			/* index of first missing line */
502	bool	ptrn_spaces_eaten;		/* ptrn was slightly malformed */
503	bool	repl_could_be_missing;		/* no + or ! lines in this hunk */
504	bool	repl_missing;			/* we are now backtracking */
505	off_t	repl_backtrack_position;	/* file pos of first repl line */
506	LINENUM	repl_patch_line;		/* input line number for same */
507	LINENUM	ptrn_copiable;			/* # of copiable lines in ptrn */
508	char	*s;
509	size_t	len;
510	int	context = 0;
511
512	while (p_end >= 0) {
513		if (p_end == p_efake)
514			p_end = p_bfake;	/* don't free twice */
515		else
516			free(p_line[p_end]);
517		p_end--;
518	}
519	p_efake = -1;
520
521	p_max = hunkmax;	/* gets reduced when --- found */
522	if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
523		line_beginning = ftello(pfp);
524		repl_beginning = 0;
525		fillcnt = 0;
526		fillsrc = 0;
527		filldst = 0;
528		ptrn_spaces_eaten = false;
529		repl_could_be_missing = true;
530		repl_missing = false;
531		repl_backtrack_position = 0;
532		repl_patch_line = 0;
533		ptrn_copiable = 0;
534
535		len = pgets(true);
536		p_input_line++;
537		if (len == 0 || strnNE(buf, "********", 8)) {
538			next_intuit_at(line_beginning, p_input_line);
539			return false;
540		}
541		p_context = 100;
542		p_hunk_beg = p_input_line + 1;
543		while (p_end < p_max) {
544			line_beginning = ftello(pfp);
545			len = pgets(true);
546			p_input_line++;
547			if (len == 0) {
548				if (p_max - p_end < 4) {
549					/* assume blank lines got chopped */
550					strlcpy(buf, "  \n", buf_size);
551				} else {
552					if (repl_beginning && repl_could_be_missing) {
553						repl_missing = true;
554						goto hunk_done;
555					}
556					fatal("unexpected end of file in patch\n");
557				}
558			}
559			p_end++;
560			if (p_end >= hunkmax)
561				fatal("Internal error: hunk larger than hunk "
562				    "buffer size");
563			p_char[p_end] = *buf;
564			p_line[p_end] = NULL;
565			switch (*buf) {
566			case '*':
567				if (strnEQ(buf, "********", 8)) {
568					if (repl_beginning && repl_could_be_missing) {
569						repl_missing = true;
570						goto hunk_done;
571					} else
572						fatal("unexpected end of hunk "
573						    "at line %ld\n",
574						    p_input_line);
575				}
576				if (p_end != 0) {
577					if (repl_beginning && repl_could_be_missing) {
578						repl_missing = true;
579						goto hunk_done;
580					}
581					fatal("unexpected *** at line %ld: %s",
582					    p_input_line, buf);
583				}
584				context = 0;
585				p_line[p_end] = savestr(buf);
586				if (out_of_mem) {
587					p_end--;
588					return false;
589				}
590				for (s = buf;
591				     *s && !isdigit((unsigned char)*s); s++)
592					;
593				if (!*s)
594					malformed();
595				if (strnEQ(s, "0,0", 3))
596					memmove(s, s + 2, strlen(s + 2) + 1);
597				p_first = strtolinenum(s, &s);
598				if (*s == ',') {
599					for (;
600					     *s && !isdigit((unsigned char)*s); s++)
601						;
602					if (!*s)
603						malformed();
604					p_ptrn_lines = strtolinenum(s, &s) - p_first + 1;
605					if (p_ptrn_lines < 0)
606						malformed();
607				} else if (p_first)
608					p_ptrn_lines = 1;
609				else {
610					p_ptrn_lines = 0;
611					p_first = 1;
612				}
613				if (p_first >= LINENUM_MAX - p_ptrn_lines ||
614				    p_ptrn_lines >= LINENUM_MAX - 6)
615					malformed();
616
617				/* we need this much at least */
618				p_max = p_ptrn_lines + 6;
619				while (p_max >= hunkmax)
620					grow_hunkmax();
621				p_max = hunkmax;
622				break;
623			case '-':
624				if (buf[1] == '-') {
625					if (repl_beginning ||
626					    (p_end != p_ptrn_lines + 1 +
627					    (p_char[p_end - 1] == '\n'))) {
628						if (p_end == 1) {
629							/*
630							 * `old' lines were omitted;
631							 * set up to fill them in
632							 * from 'new' context lines.
633							 */
634							p_end = p_ptrn_lines + 1;
635							fillsrc = p_end + 1;
636							filldst = 1;
637							fillcnt = p_ptrn_lines;
638						} else {
639							if (repl_beginning) {
640								if (repl_could_be_missing) {
641									repl_missing = true;
642									goto hunk_done;
643								}
644								fatal("duplicate \"---\" at line %ld--check line numbers at line %ld\n",
645								    p_input_line, p_hunk_beg + repl_beginning);
646							} else {
647								fatal("%s \"---\" at line %ld--check line numbers at line %ld\n",
648								    (p_end <= p_ptrn_lines
649								    ? "Premature"
650								    : "Overdue"),
651								    p_input_line, p_hunk_beg);
652							}
653						}
654					}
655					repl_beginning = p_end;
656					repl_backtrack_position = ftello(pfp);
657					repl_patch_line = p_input_line;
658					p_line[p_end] = savestr(buf);
659					if (out_of_mem) {
660						p_end--;
661						return false;
662					}
663					p_char[p_end] = '=';
664					for (s = buf; *s && !isdigit((unsigned char)*s); s++)
665						;
666					if (!*s)
667						malformed();
668					p_newfirst = strtolinenum(s, &s);
669					if (*s == ',') {
670						for (; *s && !isdigit((unsigned char)*s); s++)
671							;
672						if (!*s)
673							malformed();
674						p_repl_lines = strtolinenum(s, &s) -
675						    p_newfirst + 1;
676						if (p_repl_lines < 0)
677							malformed();
678					} else if (p_newfirst)
679						p_repl_lines = 1;
680					else {
681						p_repl_lines = 0;
682						p_newfirst = 1;
683					}
684					if (p_newfirst >= LINENUM_MAX - p_repl_lines ||
685					    p_repl_lines >= LINENUM_MAX - p_end)
686						malformed();
687					p_max = p_repl_lines + p_end;
688					if (p_max > MAXHUNKSIZE)
689						fatal("hunk too large (%ld lines) at line %ld: %s",
690						    p_max, p_input_line, buf);
691					while (p_max >= hunkmax)
692						grow_hunkmax();
693					if (p_repl_lines != ptrn_copiable &&
694					    (p_context != 0 || p_repl_lines != 1))
695						repl_could_be_missing = false;
696					break;
697				}
698				goto change_line;
699			case '+':
700			case '!':
701				repl_could_be_missing = false;
702		change_line:
703				if (buf[1] == '\n' && canonicalize)
704					strlcpy(buf + 1, " \n", buf_size - 1);
705				if (!isspace((unsigned char)buf[1]) &&
706				    buf[1] != '>' && buf[1] != '<' &&
707				    repl_beginning && repl_could_be_missing) {
708					repl_missing = true;
709					goto hunk_done;
710				}
711				if (context >= 0) {
712					if (context < p_context)
713						p_context = context;
714					context = -1000;
715				}
716				p_line[p_end] = savestr(buf + 2);
717				if (out_of_mem) {
718					p_end--;
719					return false;
720				}
721				if (p_end == p_ptrn_lines) {
722					if (remove_special_line()) {
723						int	l;
724
725						l = strlen(p_line[p_end]) - 1;
726						(p_line[p_end])[l] = 0;
727					}
728				}
729				break;
730			case '\t':
731			case '\n':	/* assume the 2 spaces got eaten */
732				if (repl_beginning && repl_could_be_missing &&
733				    (!ptrn_spaces_eaten ||
734				    diff_type == NEW_CONTEXT_DIFF)) {
735					repl_missing = true;
736					goto hunk_done;
737				}
738				p_line[p_end] = savestr(buf);
739				if (out_of_mem) {
740					p_end--;
741					return false;
742				}
743				if (p_end != p_ptrn_lines + 1) {
744					ptrn_spaces_eaten |= (repl_beginning != 0);
745					context++;
746					if (!repl_beginning)
747						ptrn_copiable++;
748					p_char[p_end] = ' ';
749				}
750				break;
751			case ' ':
752				if (!isspace((unsigned char)buf[1]) &&
753				    repl_beginning && repl_could_be_missing) {
754					repl_missing = true;
755					goto hunk_done;
756				}
757				context++;
758				if (!repl_beginning)
759					ptrn_copiable++;
760				p_line[p_end] = savestr(buf + 2);
761				if (out_of_mem) {
762					p_end--;
763					return false;
764				}
765				break;
766			default:
767				if (repl_beginning && repl_could_be_missing) {
768					repl_missing = true;
769					goto hunk_done;
770				}
771				malformed();
772			}
773			/* set up p_len for strncmp() so we don't have to */
774			/* assume null termination */
775			if (p_line[p_end])
776				p_len[p_end] = strlen(p_line[p_end]);
777			else
778				p_len[p_end] = 0;
779		}
780
781hunk_done:
782		if (p_end >= 0 && !repl_beginning)
783			fatal("no --- found in patch at line %ld\n", pch_hunk_beg());
784
785		if (repl_missing) {
786
787			/* reset state back to just after --- */
788			p_input_line = repl_patch_line;
789			for (p_end--; p_end > repl_beginning; p_end--)
790				free(p_line[p_end]);
791			fseeko(pfp, repl_backtrack_position, SEEK_SET);
792
793			/* redundant 'new' context lines were omitted - set */
794			/* up to fill them in from the old file context */
795			if (!p_context && p_repl_lines == 1) {
796				p_repl_lines = 0;
797				p_max--;
798			}
799			fillsrc = 1;
800			filldst = repl_beginning + 1;
801			fillcnt = p_repl_lines;
802			p_end = p_max;
803		} else if (!p_context && fillcnt == 1) {
804			/* the first hunk was a null hunk with no context */
805			/* and we were expecting one line -- fix it up. */
806			while (filldst < p_end) {
807				p_line[filldst] = p_line[filldst + 1];
808				p_char[filldst] = p_char[filldst + 1];
809				p_len[filldst] = p_len[filldst + 1];
810				filldst++;
811			}
812#if 0
813			repl_beginning--;	/* this doesn't need to be fixed */
814#endif
815			p_end--;
816			p_first++;	/* do append rather than insert */
817			fillcnt = 0;
818			p_ptrn_lines = 0;
819		}
820		if (diff_type == CONTEXT_DIFF &&
821		    (fillcnt || (p_first > 1 && ptrn_copiable > 2 * p_context))) {
822			if (verbose)
823				say("%s\n%s\n%s\n",
824				    "(Fascinating--this is really a new-style context diff but without",
825				    "the telltale extra asterisks on the *** line that usually indicate",
826				    "the new style...)");
827			diff_type = NEW_CONTEXT_DIFF;
828		}
829		/* if there were omitted context lines, fill them in now */
830		if (fillcnt) {
831			p_bfake = filldst;	/* remember where not to free() */
832			p_efake = filldst + fillcnt - 1;
833			while (fillcnt-- > 0) {
834				while (fillsrc <= p_end && p_char[fillsrc] != ' ')
835					fillsrc++;
836				if (fillsrc > p_end)
837					fatal("replacement text or line numbers mangled in hunk at line %ld\n",
838					    p_hunk_beg);
839				p_line[filldst] = p_line[fillsrc];
840				p_char[filldst] = p_char[fillsrc];
841				p_len[filldst] = p_len[fillsrc];
842				fillsrc++;
843				filldst++;
844			}
845			while (fillsrc <= p_end && fillsrc != repl_beginning &&
846			    p_char[fillsrc] != ' ')
847				fillsrc++;
848#ifdef DEBUGGING
849			if (debug & 64)
850				printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
851				fillsrc, filldst, repl_beginning, p_end + 1);
852#endif
853			if (fillsrc != p_end + 1 && fillsrc != repl_beginning)
854				malformed();
855			if (filldst != p_end + 1 && filldst != repl_beginning)
856				malformed();
857		}
858		if (p_line[p_end] != NULL) {
859			if (remove_special_line()) {
860				p_len[p_end] -= 1;
861				(p_line[p_end])[p_len[p_end]] = 0;
862			}
863		}
864	} else if (diff_type == UNI_DIFF) {
865		LINENUM	fillold;	/* index of old lines */
866		LINENUM	fillnew;	/* index of new lines */
867		char	ch;
868
869		line_beginning = ftello(pfp); /* file pos of the current line */
870		len = pgets(true);
871		p_input_line++;
872		if (len == 0 || strnNE(buf, "@@ -", 4)) {
873			next_intuit_at(line_beginning, p_input_line);
874			return false;
875		}
876		s = buf + 4;
877		if (!*s)
878			malformed();
879		p_first = strtolinenum(s, &s);
880		if (*s == ',') {
881			p_ptrn_lines = strtolinenum(s + 1, &s);
882		} else
883			p_ptrn_lines = 1;
884		if (*s == ' ')
885			s++;
886		if (*s != '+' || !*++s)
887			malformed();
888		p_newfirst = strtolinenum(s, &s);
889		if (*s == ',') {
890			p_repl_lines = strtolinenum(s + 1, &s);
891		} else
892			p_repl_lines = 1;
893		if (*s == ' ')
894			s++;
895		if (*s != '@')
896			malformed();
897		if (p_first >= LINENUM_MAX - p_ptrn_lines ||
898		    p_newfirst > LINENUM_MAX - p_repl_lines ||
899		    p_ptrn_lines >= LINENUM_MAX - p_repl_lines - 1)
900			malformed();
901		if (!p_ptrn_lines)
902			p_first++;	/* do append rather than insert */
903		p_max = p_ptrn_lines + p_repl_lines + 1;
904		while (p_max >= hunkmax)
905			grow_hunkmax();
906		fillold = 1;
907		fillnew = fillold + p_ptrn_lines;
908		p_end = fillnew + p_repl_lines;
909		snprintf(buf, buf_size, "*** %ld,%ld ****\n", p_first,
910		    p_first + p_ptrn_lines - 1);
911		p_line[0] = savestr(buf);
912		if (out_of_mem) {
913			p_end = -1;
914			return false;
915		}
916		p_char[0] = '*';
917		snprintf(buf, buf_size, "--- %ld,%ld ----\n", p_newfirst,
918		    p_newfirst + p_repl_lines - 1);
919		p_line[fillnew] = savestr(buf);
920		if (out_of_mem) {
921			p_end = 0;
922			return false;
923		}
924		p_char[fillnew++] = '=';
925		p_context = 100;
926		context = 0;
927		p_hunk_beg = p_input_line + 1;
928		while (fillold <= p_ptrn_lines || fillnew <= p_end) {
929			line_beginning = ftello(pfp);
930			len = pgets(true);
931			p_input_line++;
932			if (len == 0) {
933				if (p_max - fillnew < 3) {
934					/* assume blank lines got chopped */
935					strlcpy(buf, " \n", buf_size);
936				} else {
937					fatal("unexpected end of file in patch\n");
938				}
939			}
940			if (*buf == '\t' || *buf == '\n') {
941				ch = ' ';	/* assume the space got eaten */
942				s = savestr(buf);
943			} else {
944				ch = *buf;
945				s = savestr(buf + 1);
946			}
947			if (out_of_mem) {
948				while (--fillnew > p_ptrn_lines)
949					free(p_line[fillnew]);
950				p_end = fillold - 1;
951				return false;
952			}
953			switch (ch) {
954			case '-':
955				if (fillold > p_ptrn_lines) {
956					free(s);
957					p_end = fillnew - 1;
958					malformed();
959				}
960				p_char[fillold] = ch;
961				p_line[fillold] = s;
962				p_len[fillold++] = strlen(s);
963				if (fillold > p_ptrn_lines) {
964					if (remove_special_line()) {
965						p_len[fillold - 1] -= 1;
966						s[p_len[fillold - 1]] = 0;
967					}
968				}
969				break;
970			case '=':
971				ch = ' ';
972				/* FALL THROUGH */
973			case ' ':
974				if (fillold > p_ptrn_lines) {
975					free(s);
976					while (--fillnew > p_ptrn_lines)
977						free(p_line[fillnew]);
978					p_end = fillold - 1;
979					malformed();
980				}
981				context++;
982				p_char[fillold] = ch;
983				p_line[fillold] = s;
984				p_len[fillold++] = strlen(s);
985				s = savestr(s);
986				if (out_of_mem) {
987					while (--fillnew > p_ptrn_lines)
988						free(p_line[fillnew]);
989					p_end = fillold - 1;
990					return false;
991				}
992				if (fillold > p_ptrn_lines) {
993					if (remove_special_line()) {
994						p_len[fillold - 1] -= 1;
995						s[p_len[fillold - 1]] = 0;
996					}
997				}
998				/* FALL THROUGH */
999			case '+':
1000				if (fillnew > p_end) {
1001					free(s);
1002					while (--fillnew > p_ptrn_lines)
1003						free(p_line[fillnew]);
1004					p_end = fillold - 1;
1005					malformed();
1006				}
1007				p_char[fillnew] = ch;
1008				p_line[fillnew] = s;
1009				p_len[fillnew++] = strlen(s);
1010				if (fillold > p_ptrn_lines) {
1011					if (remove_special_line()) {
1012						p_len[fillnew - 1] -= 1;
1013						s[p_len[fillnew - 1]] = 0;
1014					}
1015				}
1016				break;
1017			default:
1018				p_end = fillnew;
1019				malformed();
1020			}
1021			if (ch != ' ' && context > 0) {
1022				if (context < p_context)
1023					p_context = context;
1024				context = -1000;
1025			}
1026		}		/* while */
1027	} else {		/* normal diff--fake it up */
1028		char	hunk_type;
1029		int	i;
1030		LINENUM	min, max;
1031
1032		line_beginning = ftello(pfp);
1033		p_context = 0;
1034		len = pgets(true);
1035		p_input_line++;
1036		if (len == 0 || !isdigit((unsigned char)*buf)) {
1037			next_intuit_at(line_beginning, p_input_line);
1038			return false;
1039		}
1040		p_first = strtolinenum(buf, &s);
1041		if (*s == ',') {
1042			p_ptrn_lines = strtolinenum(s + 1, &s) - p_first + 1;
1043			if (p_ptrn_lines < 0)
1044				malformed();
1045		} else
1046			p_ptrn_lines = (*s != 'a');
1047		hunk_type = *s;
1048		if (hunk_type == 'a')
1049			p_first++;	/* do append rather than insert */
1050		min = strtolinenum(s + 1, &s);
1051		if (*s == ',')
1052			max = strtolinenum(s + 1, &s);
1053		else
1054			max = min;
1055		if (min < 0 || min > max || max - min == LINENUM_MAX)
1056			malformed();
1057		if (hunk_type == 'd')
1058			min++;
1059		p_newfirst = min;
1060		p_repl_lines = max - min + 1;
1061		if (p_newfirst > LINENUM_MAX - p_repl_lines ||
1062		    p_ptrn_lines >= LINENUM_MAX - p_repl_lines - 1)
1063			malformed();
1064		p_end = p_ptrn_lines + p_repl_lines + 1;
1065		if (p_end > MAXHUNKSIZE)
1066			fatal("hunk too large (%ld lines) at line %ld: %s",
1067			    p_end, p_input_line, buf);
1068		while (p_end >= hunkmax)
1069			grow_hunkmax();
1070		snprintf(buf, buf_size, "*** %ld,%ld\n", p_first,
1071		    p_first + p_ptrn_lines - 1);
1072		p_line[0] = savestr(buf);
1073		if (out_of_mem) {
1074			p_end = -1;
1075			return false;
1076		}
1077		p_char[0] = '*';
1078		for (i = 1; i <= p_ptrn_lines; i++) {
1079			len = pgets(true);
1080			p_input_line++;
1081			if (len == 0)
1082				fatal("unexpected end of file in patch at line %ld\n",
1083				    p_input_line);
1084			if (*buf != '<')
1085				fatal("< expected at line %ld of patch\n",
1086				    p_input_line);
1087			p_line[i] = savestr(buf + 2);
1088			if (out_of_mem) {
1089				p_end = i - 1;
1090				return false;
1091			}
1092			p_len[i] = strlen(p_line[i]);
1093			p_char[i] = '-';
1094		}
1095
1096		if (remove_special_line()) {
1097			p_len[i - 1] -= 1;
1098			(p_line[i - 1])[p_len[i - 1]] = 0;
1099		}
1100		if (hunk_type == 'c') {
1101			len = pgets(true);
1102			p_input_line++;
1103			if (len == 0)
1104				fatal("unexpected end of file in patch at line %ld\n",
1105				    p_input_line);
1106			if (*buf != '-')
1107				fatal("--- expected at line %ld of patch\n",
1108				    p_input_line);
1109		}
1110		snprintf(buf, buf_size, "--- %ld,%ld\n", min, max);
1111		p_line[i] = savestr(buf);
1112		if (out_of_mem) {
1113			p_end = i - 1;
1114			return false;
1115		}
1116		p_char[i] = '=';
1117		for (i++; i <= p_end; i++) {
1118			len = pgets(true);
1119			p_input_line++;
1120			if (len == 0)
1121				fatal("unexpected end of file in patch at line %ld\n",
1122				    p_input_line);
1123			if (*buf != '>')
1124				fatal("> expected at line %ld of patch\n",
1125				    p_input_line);
1126			p_line[i] = savestr(buf + 2);
1127			if (out_of_mem) {
1128				p_end = i - 1;
1129				return false;
1130			}
1131			p_len[i] = strlen(p_line[i]);
1132			p_char[i] = '+';
1133		}
1134
1135		if (remove_special_line()) {
1136			p_len[i - 1] -= 1;
1137			(p_line[i - 1])[p_len[i - 1]] = 0;
1138		}
1139	}
1140	if (reverse)		/* backwards patch? */
1141		if (!pch_swap())
1142			say("Not enough memory to swap next hunk!\n");
1143#ifdef DEBUGGING
1144	if (debug & 2) {
1145		int	i;
1146		char	special;
1147
1148		for (i = 0; i <= p_end; i++) {
1149			if (i == p_ptrn_lines)
1150				special = '^';
1151			else
1152				special = ' ';
1153			fprintf(stderr, "%3d %c %c %s", i, p_char[i],
1154			    special, p_line[i]);
1155			fflush(stderr);
1156		}
1157	}
1158#endif
1159	if (p_end + 1 < hunkmax)/* paranoia reigns supreme... */
1160		p_char[p_end + 1] = '^';	/* add a stopper for apply_hunk */
1161	return true;
1162}
1163
1164/*
1165 * Input a line from the patch file.
1166 * Worry about indentation if do_indent is true.
1167 * The line is read directly into the buf global variable which
1168 * is resized if necessary in order to hold the complete line.
1169 * Returns the number of characters read including the terminating
1170 * '\n', if any.
1171 */
1172size_t
1173pgets(bool do_indent)
1174{
1175	char *line;
1176	size_t len;
1177	int indent = 0, skipped = 0;
1178
1179	line = fgetln(pfp, &len);
1180	if (line != NULL) {
1181		if (len + 1 > buf_size) {
1182			while (len + 1 > buf_size)
1183				buf_size *= 2;
1184			free(buf);
1185			buf = malloc(buf_size);
1186			if (buf == NULL)
1187				fatal("out of memory\n");
1188		}
1189		if (do_indent == 1 && p_indent) {
1190			for (;
1191			    indent < p_indent && (*line == ' ' || *line == '\t' || *line == 'X');
1192			    line++, skipped++) {
1193				if (*line == '\t')
1194					indent += 8 - (indent %7);
1195				else
1196					indent++;
1197			}
1198		}
1199		memcpy(buf, line, len - skipped);
1200		buf[len - skipped] = '\0';
1201	}
1202	return len;
1203}
1204
1205
1206/*
1207 * Reverse the old and new portions of the current hunk.
1208 */
1209bool
1210pch_swap(void)
1211{
1212	char	**tp_line;	/* the text of the hunk */
1213	unsigned short	*tp_len;/* length of each line */
1214	char	*tp_char;	/* +, -, and ! */
1215	LINENUM	i;
1216	LINENUM	n;
1217	bool	blankline = false;
1218	char	*s;
1219
1220	i = p_first;
1221	p_first = p_newfirst;
1222	p_newfirst = i;
1223
1224	/* make a scratch copy */
1225
1226	tp_line = p_line;
1227	tp_len = p_len;
1228	tp_char = p_char;
1229	p_line = NULL;	/* force set_hunkmax to allocate again */
1230	p_len = NULL;
1231	p_char = NULL;
1232	set_hunkmax();
1233	if (p_line == NULL || p_len == NULL || p_char == NULL) {
1234
1235		free(p_line);
1236		p_line = tp_line;
1237		free(p_len);
1238		p_len = tp_len;
1239		free(p_char);
1240		p_char = tp_char;
1241		return false;	/* not enough memory to swap hunk! */
1242	}
1243	/* now turn the new into the old */
1244
1245	i = p_ptrn_lines + 1;
1246	if (tp_char[i] == '\n') {	/* account for possible blank line */
1247		blankline = true;
1248		i++;
1249	}
1250	if (p_efake >= 0) {	/* fix non-freeable ptr range */
1251		if (p_efake <= i)
1252			n = p_end - i + 1;
1253		else
1254			n = -i;
1255		p_efake += n;
1256		p_bfake += n;
1257	}
1258	for (n = 0; i <= p_end; i++, n++) {
1259		p_line[n] = tp_line[i];
1260		p_char[n] = tp_char[i];
1261		if (p_char[n] == '+')
1262			p_char[n] = '-';
1263		p_len[n] = tp_len[i];
1264	}
1265	if (blankline) {
1266		i = p_ptrn_lines + 1;
1267		p_line[n] = tp_line[i];
1268		p_char[n] = tp_char[i];
1269		p_len[n] = tp_len[i];
1270		n++;
1271	}
1272	if (p_char[0] != '=')
1273		fatal("Malformed patch at line %ld: expected '=' found '%c'\n",
1274		    p_input_line, p_char[0]);
1275	p_char[0] = '*';
1276	for (s = p_line[0]; *s; s++)
1277		if (*s == '-')
1278			*s = '*';
1279
1280	/* now turn the old into the new */
1281
1282	if (p_char[0] != '*')
1283		fatal("Malformed patch at line %ld: expected '*' found '%c'\n",
1284		    p_input_line, p_char[0]);
1285	tp_char[0] = '=';
1286	for (s = tp_line[0]; *s; s++)
1287		if (*s == '*')
1288			*s = '-';
1289	for (i = 0; n <= p_end; i++, n++) {
1290		p_line[n] = tp_line[i];
1291		p_char[n] = tp_char[i];
1292		if (p_char[n] == '-')
1293			p_char[n] = '+';
1294		p_len[n] = tp_len[i];
1295	}
1296
1297	if (i != p_ptrn_lines + 1)
1298		fatal("Malformed patch at line %ld: expected %ld lines, "
1299		    "got %ld\n",
1300		    p_input_line, p_ptrn_lines + 1, i);
1301
1302	i = p_ptrn_lines;
1303	p_ptrn_lines = p_repl_lines;
1304	p_repl_lines = i;
1305
1306	free(tp_line);
1307	free(tp_len);
1308	free(tp_char);
1309
1310	return true;
1311}
1312
1313/*
1314 * Return the specified line position in the old file of the old context.
1315 */
1316LINENUM
1317pch_first(void)
1318{
1319	return p_first;
1320}
1321
1322/*
1323 * Return the number of lines of old context.
1324 */
1325LINENUM
1326pch_ptrn_lines(void)
1327{
1328	return p_ptrn_lines;
1329}
1330
1331/*
1332 * Return the probable line position in the new file of the first line.
1333 */
1334LINENUM
1335pch_newfirst(void)
1336{
1337	return p_newfirst;
1338}
1339
1340/*
1341 * Return the number of lines in the replacement text including context.
1342 */
1343LINENUM
1344pch_repl_lines(void)
1345{
1346	return p_repl_lines;
1347}
1348
1349/*
1350 * Return the number of lines in the whole hunk.
1351 */
1352LINENUM
1353pch_end(void)
1354{
1355	return p_end;
1356}
1357
1358/*
1359 * Return the number of context lines before the first changed line.
1360 */
1361LINENUM
1362pch_context(void)
1363{
1364	return p_context;
1365}
1366
1367/*
1368 * Return the length of a particular patch line.
1369 */
1370unsigned short
1371pch_line_len(LINENUM line)
1372{
1373	return p_len[line];
1374}
1375
1376/*
1377 * Return the control character (+, -, *, !, etc) for a patch line.
1378 */
1379char
1380pch_char(LINENUM line)
1381{
1382	return p_char[line];
1383}
1384
1385/*
1386 * Return a pointer to a particular patch line.
1387 */
1388char *
1389pfetch(LINENUM line)
1390{
1391	return p_line[line];
1392}
1393
1394/*
1395 * Return where in the patch file this hunk began, for error messages.
1396 */
1397LINENUM
1398pch_hunk_beg(void)
1399{
1400	return p_hunk_beg;
1401}
1402
1403/*
1404 * Apply an ed script by feeding ed itself.
1405 */
1406void
1407do_ed_script(void)
1408{
1409	char	*t;
1410	off_t	beginning_of_this_line;
1411	FILE	*pipefp = NULL;
1412	int	continuation;
1413
1414	if (!skip_rest_of_patch) {
1415		if (copy_file(filearg[0], TMPOUTNAME) < 0) {
1416			unlink(TMPOUTNAME);
1417			fatal("can't create temp file %s", TMPOUTNAME);
1418		}
1419		snprintf(buf, buf_size, "%s%s%s", _PATH_RED,
1420		    verbose ? " " : " -s ", TMPOUTNAME);
1421		pipefp = popen(buf, "w");
1422	}
1423	for (;;) {
1424		beginning_of_this_line = ftello(pfp);
1425		if (pgets(true) == 0) {
1426			next_intuit_at(beginning_of_this_line, p_input_line);
1427			break;
1428		}
1429		p_input_line++;
1430		for (t = buf; isdigit((unsigned char)*t) || *t == ','; t++)
1431			;
1432		/* POSIX defines allowed commands as {a,c,d,i,s} */
1433		if (isdigit((unsigned char)*buf) &&
1434		    (*t == 'a' || *t == 'c' || *t == 'd' || *t == 'i' || *t == 's')) {
1435			if (pipefp != NULL)
1436				fputs(buf, pipefp);
1437			if (*t == 's') {
1438				for (;;) {
1439					continuation = 0;
1440					t = strchr(buf, '\0') - 1;
1441					while (--t >= buf && *t == '\\')
1442						continuation = !continuation;
1443					if (!continuation ||
1444					    pgets(true) == 0)
1445						break;
1446					if (pipefp != NULL)
1447						fputs(buf, pipefp);
1448				}
1449			} else if (*t != 'd') {
1450				while (pgets(true)) {
1451					p_input_line++;
1452					if (pipefp != NULL)
1453						fputs(buf, pipefp);
1454					if (strEQ(buf, ".\n"))
1455						break;
1456				}
1457			}
1458		} else {
1459			next_intuit_at(beginning_of_this_line, p_input_line);
1460			break;
1461		}
1462	}
1463	if (pipefp == NULL)
1464		return;
1465	fprintf(pipefp, "w\n");
1466	fprintf(pipefp, "q\n");
1467	fflush(pipefp);
1468	pclose(pipefp);
1469	ignore_signals();
1470	if (!check_only) {
1471		if (move_file(TMPOUTNAME, outname) < 0) {
1472			toutkeep = true;
1473			chmod(TMPOUTNAME, filemode);
1474		} else
1475			chmod(outname, filemode);
1476	}
1477	set_signals(1);
1478}
1479
1480/*
1481 * Choose the name of the file to be patched based on POSIX rules.
1482 * NOTE: the POSIX rules are amazingly stupid and we only follow them
1483 *       if the user specified --posix or set POSIXLY_CORRECT.
1484 */
1485static char *
1486posix_name(const struct file_name *names, bool assume_exists)
1487{
1488	char *path = NULL;
1489	int i;
1490
1491	/*
1492	 * POSIX states that the filename will be chosen from one
1493	 * of the old, new and index names (in that order) if
1494	 * the file exists relative to CWD after -p stripping.
1495	 */
1496	for (i = 0; i < MAX_FILE; i++) {
1497		if (names[i].path != NULL && names[i].exists) {
1498			path = names[i].path;
1499			break;
1500		}
1501	}
1502	if (path == NULL && !assume_exists) {
1503		/*
1504		 * No files found, look for something we can checkout from
1505		 * RCS/SCCS dirs.  Same order as above.
1506		 */
1507		for (i = 0; i < MAX_FILE; i++) {
1508			if (names[i].path != NULL &&
1509			    (path = checked_in(names[i].path)) != NULL)
1510				break;
1511		}
1512		/*
1513		 * Still no match?  Check to see if the diff could be creating
1514		 * a new file.
1515		 */
1516		if (path == NULL && ok_to_create_file &&
1517		    names[NEW_FILE].path != NULL)
1518			path = names[NEW_FILE].path;
1519	}
1520
1521	return path ? xstrdup(path) : NULL;
1522}
1523
1524static char *
1525compare_names(const struct file_name *names, bool assume_exists, int phase)
1526{
1527	size_t min_components, min_baselen, min_len, tmp;
1528	char *best = NULL;
1529	char *path;
1530	int i;
1531
1532	/*
1533	 * The "best" name is the one with the fewest number of path
1534	 * components, the shortest basename length, and the shortest
1535	 * overall length (in that order).  We only use the Index: file
1536	 * if neither of the old or new files could be intuited from
1537	 * the diff header.
1538	 */
1539	min_components = min_baselen = min_len = SIZE_MAX;
1540	for (i = INDEX_FILE; i >= OLD_FILE; i--) {
1541		path = names[i].path;
1542		if (path == NULL ||
1543		    (phase == 1 && !names[i].exists && !assume_exists) ||
1544		    (phase == 2 && checked_in(path) == NULL))
1545			continue;
1546		if ((tmp = num_components(path)) > min_components)
1547			continue;
1548		if (tmp < min_components) {
1549			min_components = tmp;
1550			best = path;
1551		}
1552		if ((tmp = strlen(basename(path))) > min_baselen)
1553			continue;
1554		if (tmp < min_baselen) {
1555			min_baselen = tmp;
1556			best = path;
1557		}
1558		if ((tmp = strlen(path)) > min_len)
1559			continue;
1560		min_len = tmp;
1561		best = path;
1562	}
1563	return best;
1564}
1565
1566/*
1567 * Choose the name of the file to be patched based the "best" one
1568 * available.
1569 */
1570static char *
1571best_name(const struct file_name *names, bool assume_exists)
1572{
1573	char *best;
1574
1575	best = compare_names(names, assume_exists, 1);
1576	if (best == NULL) {
1577		best = compare_names(names, assume_exists, 2);
1578		/*
1579		 * Still no match?  Check to see if the diff could be creating
1580		 * a new file.
1581		 */
1582		if (best == NULL && ok_to_create_file &&
1583		    names[NEW_FILE].path != NULL)
1584			best = names[NEW_FILE].path;
1585	}
1586
1587	return best ? xstrdup(best) : NULL;
1588}
1589
1590static size_t
1591num_components(const char *path)
1592{
1593	size_t n;
1594	const char *cp;
1595
1596	for (n = 0, cp = path; (cp = strchr(cp, '/')) != NULL; n++, cp++) {
1597		while (*cp == '/')
1598			cp++;		/* skip consecutive slashes */
1599	}
1600	return n;
1601}
1602
1603/*
1604 * Convert number at NPTR into LINENUM and save address of first
1605 * character that is not a digit in ENDPTR.  If conversion is not
1606 * possible, call fatal.
1607 */
1608static LINENUM
1609strtolinenum(char *nptr, char **endptr)
1610{
1611	LINENUM rv;
1612	char c;
1613	char *p;
1614	const char *errstr;
1615
1616	for (p = nptr; isdigit((unsigned char)*p); p++)
1617		;
1618
1619	if (p == nptr)
1620		malformed();
1621
1622	c = *p;
1623	*p = '\0';
1624
1625	rv = strtonum(nptr, 0, LINENUM_MAX, &errstr);
1626	if (errstr != NULL)
1627		fatal("invalid line number at line %ld: `%s' is %s\n",
1628		    p_input_line, nptr, errstr);
1629
1630	*p = c;
1631	*endptr = p;
1632
1633	return rv;
1634}
1635