Gotweb

Blob

Date:: Thu Jun 23 14:09:35 2022 UTC
Message:: use the commitid in the patch diff3 conflict header suggested by and ok stsp@
Actions:: History | Blame | Raw File
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 
22 /*
23  * Copyright (c) 2022 Omar Polo <op@openbsd.org>
24  *
25  * Permission to use, copy, modify, and distribute this software for any
26  * purpose with or without fee is hereby granted, provided that the above
27  * copyright notice and this permission notice appear in all copies.
28  *
29  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
30  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
31  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
32  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
33  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
34  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
35  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
36  */
37 
38 #include <sys/types.h>
39 #include <sys/uio.h>
40 
41 #include <ctype.h>
42 #include <limits.h>
43 #include <paths.h>
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "got_error.h"
51 #include "got_object.h"
52 
53 #include "got_compat.h"
54 
55 #include "got_lib_delta.h"
56 #include "got_lib_object.h"
57 #include "got_lib_privsep.h"
58 #include "got_lib_sha1.h"
59 
60 struct imsgbuf ibuf;
61 
62 static const struct got_error *
63 send_patch(const char *oldname, const char *newname, const char *commitid,
64     const char *blob, int git)
65 {
66 	struct got_imsg_patch p;
67 
68 	memset(&p, 0, sizeof(p));
69 
70 	if (oldname != NULL)
71 		strlcpy(p.old, oldname, sizeof(p.old));
72 
73 	if (newname != NULL)
74 		strlcpy(p.new, newname, sizeof(p.new));
75 
76 	if (commitid != NULL && blob != NULL) {
77 		strlcpy(p.cid, commitid, sizeof(p.cid));
78 		strlcpy(p.blob, blob, sizeof(p.blob));
79 	}
80 
81 	p.git = git;
82 	if (imsg_compose(&ibuf, GOT_IMSG_PATCH, 0, 0, -1, &p, sizeof(p)) == -1)
83 		return got_error_from_errno("imsg_compose GOT_IMSG_PATCH");
84 	return NULL;
85 }
86 
87 static const struct got_error *
88 send_patch_done(void)
89 {
90 	if (imsg_compose(&ibuf, GOT_IMSG_PATCH_DONE, 0, 0, -1,
91 	    NULL, 0) == -1)
92 		return got_error_from_errno("imsg_compose GOT_IMSG_PATCH_EOF");
93 	if (imsg_flush(&ibuf) == -1)
94 		return got_error_from_errno("imsg_flush");
95 	return NULL;
96 }
97 
98 /* based on fetchname from usr.bin/patch/util.c */
99 static const struct got_error *
100 filename(const char *at, char **name)
101 {
102 	char	*tmp, *t;
103 
104 	*name = NULL;
105 	if (*at == '\0')
106 		return NULL;
107 
108 	while (isspace((unsigned char)*at))
109 		at++;
110 
111 	/* files can be created or removed by diffing against /dev/null */
112 	if (!strncmp(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
113 		return NULL;
114 
115 	tmp = strdup(at);
116 	if (tmp == NULL)
117 		return got_error_from_errno("strdup");
118 	if ((t = strchr(tmp, '\t')) != NULL)
119 		*t = '\0';
120 	if ((t = strchr(tmp, '\n')) != NULL)
121 		*t = '\0';
122 
123 	*name = strdup(tmp);
124 	free(tmp);
125 	if (*name == NULL)
126 		return got_error_from_errno("strdup");
127 	return NULL;
128 }
129 
130 static const struct got_error *
131 blobid(const char *line, char **blob)
132 {
133 	uint8_t digest[SHA1_DIGEST_LENGTH];
134 	size_t len;
135 
136 	*blob = NULL;
137 
138 	len = strspn(line, "0123456789abcdefABCDEF");
139 	if ((*blob = strndup(line, len)) == NULL)
140 		return got_error_from_errno("strndup");
141 
142 	if (!got_parse_sha1_digest(digest, *blob)) {
143 		/* silently ignore invalid blob ids */
144 		free(*blob);
145 		*blob = NULL;
146 	}
147 	return NULL;
148 }
149 
150 static const struct got_error *
151 find_patch(int *done, FILE *fp)
152 {
153 	const struct got_error *err = NULL;
154 	char	*old = NULL, *new = NULL;
155 	char	*commitid = NULL, *blob = NULL;
156 	char	*line = NULL;
157 	size_t	 linesize = 0;
158 	ssize_t	 linelen;
159 	int	 create, rename = 0, git = 0;
160 
161 	while ((linelen = getline(&line, &linesize, fp)) != -1) {
162 		/*
163 		 * Ignore the Index name like GNU and larry' patch,
164 		 * we don't have to follow POSIX.
165 		 */
166 
167 		if (!strncmp(line, "--- ", 4)) {
168 			free(old);
169 			err = filename(line+4, &old);
170 		} else if (rename && !strncmp(line, "rename from ", 12)) {
171 			free(old);
172 			err = filename(line+12, &old);
173 		} else if (!strncmp(line, "+++ ", 4)) {
174 			free(new);
175 			err = filename(line+4, &new);
176 		} else if (!git && !strncmp(line, "blob - ", 7)) {
177 			free(blob);
178 			err = blobid(line + 7, &blob);
179 		} else if (rename && !strncmp(line, "rename to ", 10)) {
180 			free(new);
181 			err = filename(line + 10, &new);
182 		} else if (git && !strncmp(line, "similarity index 100%", 21))
183 			rename = 1;
184 		else if (!strncmp(line, "diff --git a/", 13)) {
185 			git = 1;
186 			free(commitid);
187 			commitid = NULL;
188 			free(blob);
189 			blob = NULL;
190 		} else if (!git && !strncmp(line, "diff ", 5)) {
191 			free(commitid);
192 			err = blobid(line + 5, &commitid);
193 		}
194 
195 		if (err)
196 			break;
197 
198 		/*
199 		 * Git-style diffs with "similarity index 100%" don't
200 		 * have any hunks and ends with the "rename to foobar"
201 		 * line.
202 		 */
203 		if (rename && old != NULL && new != NULL) {
204 			*done = 1;
205 			err = send_patch(old, new, commitid,
206 			    blob, git);
207 			break;
208 		}
209 
210 		if (!strncmp(line, "@@ -", 4)) {
211 			create = !strncmp(line+4, "0,0", 3);
212 			if ((old == NULL && new == NULL) ||
213 			    (!create && old == NULL))
214 				err = got_error(GOT_ERR_PATCH_MALFORMED);
215 			else
216 				err = send_patch(old, new, commitid,
217 				    blob, git);
218 
219 			if (err)
220 				break;
221 
222 			/* rewind to previous line */
223 			if (fseeko(fp, -linelen, SEEK_CUR) == -1)
224 				err = got_error_from_errno("fseeko");
225 			break;
226 		}
227 	}
228 
229 	free(old);
230 	free(new);
231 	free(commitid);
232 	free(blob);
233 	free(line);
234 	if (ferror(fp) && err == NULL)
235 		err = got_error_from_errno("getline");
236 	if (feof(fp) && err == NULL)
237 		err = got_error(GOT_ERR_NO_PATCH);
238 	return err;
239 }
240 
241 static const struct got_error *
242 strtolnum(char **str, int *n)
243 {
244 	char		*p, c;
245 	const char	*errstr;
246 
247 	for (p = *str; isdigit((unsigned char)*p); ++p)
248 		/* nop */;
249 
250 	c = *p;
251 	*p = '\0';
252 
253 	*n = strtonum(*str, 0, INT_MAX, &errstr);
254 	if (errstr != NULL)
255 		return got_error(GOT_ERR_PATCH_MALFORMED);
256 
257 	*p = c;
258 	*str = p;
259 	return NULL;
260 }
261 
262 static const struct got_error *
263 parse_hdr(char *s, int *done, struct got_imsg_patch_hunk *hdr)
264 {
265 	static const struct got_error *err = NULL;
266 
267 	if (strncmp(s, "@@ -", 4)) {
268 		*done = 1;
269 		return NULL;
270 	}
271 
272 	s += 4;
273 	if (!*s)
274 		return NULL;
275 	err = strtolnum(&s, &hdr->oldfrom);
276 	if (err)
277 		return err;
278 	if (*s == ',') {
279 		s++;
280 		err = strtolnum(&s, &hdr->oldlines);
281 		if (err)
282 			return err;
283 	} else
284 		hdr->oldlines = 1;
285 
286 	if (*s == ' ')
287 		s++;
288 
289 	if (*s != '+' || !*++s)
290 		return got_error(GOT_ERR_PATCH_MALFORMED);
291 	err = strtolnum(&s, &hdr->newfrom);
292 	if (err)
293 		return err;
294 	if (*s == ',') {
295 		s++;
296 		err = strtolnum(&s, &hdr->newlines);
297 		if (err)
298 			return err;
299 	} else
300 		hdr->newlines = 1;
301 
302 	if (*s == ' ')
303 		s++;
304 
305 	if (*s != '@')
306 		return got_error(GOT_ERR_PATCH_MALFORMED);
307 
308 	if (hdr->oldfrom >= INT_MAX - hdr->oldlines ||
309 	    hdr->newfrom >= INT_MAX - hdr->newlines ||
310 	    /* not so sure about this one */
311 	    hdr->oldlines >= INT_MAX - hdr->newlines - 1 ||
312 	    (hdr->oldlines == 0 && hdr->newlines == 0))
313 		return got_error(GOT_ERR_PATCH_MALFORMED);
314 
315 	if (hdr->oldlines == 0) {
316 		/* larry says to "do append rather than insert"; I don't
317 		 * quite get it, but i trust him.
318 		 */
319 		hdr->oldfrom++;
320 	}
321 
322 	if (imsg_compose(&ibuf, GOT_IMSG_PATCH_HUNK, 0, 0, -1,
323 	    hdr, sizeof(*hdr)) == -1)
324 		return got_error_from_errno(
325 		    "imsg_compose GOT_IMSG_PATCH_HUNK");
326 	return NULL;
327 }
328 
329 static const struct got_error *
330 send_line(const char *line)
331 {
332 	static const struct got_error *err = NULL;
333 	char *p = NULL;
334 
335 	if (*line != '+' && *line != '-' && *line != ' ' && *line != '\\') {
336 		if (asprintf(&p, " %s", line) == -1)
337 			return got_error_from_errno("asprintf");
338 		line = p;
339 	}
340 
341 	if (imsg_compose(&ibuf, GOT_IMSG_PATCH_LINE, 0, 0, -1,
342 	    line, strlen(line) + 1) == -1)
343 		err = got_error_from_errno(
344 		    "imsg_compose GOT_IMSG_PATCH_LINE");
345 
346 	free(p);
347 	return err;
348 }
349 
350 static const struct got_error *
351 peek_special_line(FILE *fp)
352 {
353 	const struct got_error *err;
354 	int ch;
355 
356 	ch = fgetc(fp);
357 	if (ch != EOF && ch != '\\') {
358 		ungetc(ch, fp);
359 		return NULL;
360 	}
361 
362 	if (ch == '\\') {
363 		err = send_line("\\");
364 		if (err)
365 			return err;
366 	}
367 
368 	while (ch != EOF && ch != '\n')
369 		ch = fgetc(fp);
370 
371 	if (ch != EOF || feof(fp))
372 		return NULL;
373 	return got_error(GOT_ERR_IO);
374 }
375 
376 static const struct got_error *
377 parse_hunk(FILE *fp, int *done)
378 {
379 	static const struct got_error *err = NULL;
380 	struct got_imsg_patch_hunk hdr;
381 	char	*line = NULL, ch;
382 	size_t	 linesize = 0;
383 	ssize_t	 linelen;
384 	int	 leftold, leftnew;
385 
386 	linelen = getline(&line, &linesize, fp);
387 	if (linelen == -1) {
388 		*done = 1;
389 		goto done;
390 	}
391 
392 	err = parse_hdr(line, done, &hdr);
393 	if (err)
394 		goto done;
395 	if (*done) {
396 		if (fseeko(fp, -linelen, SEEK_CUR) == -1)
397 			err = got_error_from_errno("fseeko");
398 		goto done;
399 	}
400 
401 	leftold = hdr.oldlines;
402 	leftnew = hdr.newlines;
403 
404 	while (leftold > 0 || leftnew > 0) {
405 		linelen = getline(&line, &linesize, fp);
406 		if (linelen == -1) {
407 			if (ferror(fp)) {
408 				err = got_error_from_errno("getline");
409 				goto done;
410 			}
411 
412 			/* trailing newlines may be chopped */
413 			if (leftold < 3 && leftnew < 3) {
414 				*done = 1;
415 				break;
416 			}
417 
418 			err = got_error(GOT_ERR_PATCH_TRUNCATED);
419 			goto done;
420 		}
421 		if (line[linelen - 1] == '\n')
422 			line[linelen - 1] = '\0';
423 
424 		/* usr.bin/patch allows '=' as context char */
425 		if (*line == '=')
426 			*line = ' ';
427 
428 		ch = *line;
429 		if (ch == '\t' || ch == '\0')
430 			ch = ' ';	/* the space got eaten */
431 
432 		switch (ch) {
433 		case '-':
434 			leftold--;
435 			break;
436 		case ' ':
437 			leftold--;
438 			leftnew--;
439 			break;
440 		case '+':
441 			leftnew--;
442 			break;
443 		default:
444 			err = got_error(GOT_ERR_PATCH_MALFORMED);
445 			goto done;
446 		}
447 
448 		if (leftold < 0 || leftnew < 0) {
449 			err = got_error(GOT_ERR_PATCH_MALFORMED);
450 			goto done;
451 		}
452 
453 		err = send_line(line);
454 		if (err)
455 			goto done;
456 
457 		if ((ch == '-' && leftold == 0) ||
458 		    (ch == '+' && leftnew == 0)) {
459 			err = peek_special_line(fp);
460 			if (err)
461 				goto done;
462 		}
463 	}
464 
465 done:
466 	free(line);
467 	return err;
468 }
469 
470 static const struct got_error *
471 read_patch(struct imsgbuf *ibuf, int fd)
472 {
473 	const struct got_error *err = NULL;
474 	FILE *fp;
475 	int patch_found = 0;
476 
477 	if ((fp = fdopen(fd, "r")) == NULL) {
478 		err = got_error_from_errno("fdopen");
479 		close(fd);
480 		return err;
481 	}
482 
483 	while (!feof(fp)) {
484 		int done = 0;
485 
486 		err = find_patch(&done, fp);
487 		if (err)
488 			goto done;
489 
490 		patch_found = 1;
491 
492 		while (!done) {
493 			err = parse_hunk(fp, &done);
494 			if (err)
495 				goto done;
496 		}
497 
498 		err = send_patch_done();
499 		if (err)
500 			goto done;
501 	}
502 
503 done:
504 	fclose(fp);
505 
506 	/* ignore trailing gibberish */
507 	if (err != NULL && err->code == GOT_ERR_NO_PATCH && patch_found)
508 		err = NULL;
509 
510 	return err;
511 }
512 
513 int
514 main(int argc, char **argv)
515 {
516 	const struct got_error *err = NULL;
517 	struct imsg imsg;
518 #if 0
519 	static int attached;
520 	while (!attached)
521 		sleep(1);
522 #endif
523 
524 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
525 #ifndef PROFILE
526 	/* revoke access to most system calls */
527 	if (pledge("stdio recvfd", NULL) == -1) {
528 		err = got_error_from_errno("pledge");
529 		got_privsep_send_error(&ibuf, err);
530 		return 1;
531 	}
532 
533 	/* revoke fs access */
534 	if (landlock_no_fs() == -1) {
535 		err = got_error_from_errno("landlock_no_fs");
536 		got_privsep_send_error(&ibuf, err);
537 		return 1;
538 	}
539 #endif
540 
541 	err = got_privsep_recv_imsg(&imsg, &ibuf, 0);
542 	if (err)
543 		goto done;
544 	if (imsg.hdr.type != GOT_IMSG_PATCH_FILE || imsg.fd == -1) {
545 		err = got_error(GOT_ERR_PRIVSEP_MSG);
546 		goto done;
547 	}
548 
549 	err = read_patch(&ibuf, imsg.fd);
550 	if (err)
551 		goto done;
552 	if (imsg_compose(&ibuf, GOT_IMSG_PATCH_EOF, 0, 0, -1,
553 	    NULL, 0) == -1) {
554 		err = got_error_from_errno("imsg_compose GOT_IMSG_PATCH_EOF");
555 		goto done;
556 	}
557 	err = got_privsep_flush_imsg(&ibuf);
558 done:
559 	imsg_free(&imsg);
560 	if (err != NULL) {
561 		got_privsep_send_error(&ibuf, err);
562 		err = NULL;
563 	}
564 	if (close(GOT_IMSG_FD_CHILD) == -1 && err == NULL)
565 		err = got_error_from_errno("close");
566 	if (err && err->code != GOT_ERR_PRIVSEP_PIPE)
567 		fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
568 	return err ? 1 : 0;
569 }