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Date:: Mon Jun 11 20:02:49 2018 UTC
Message:: handle EILSEQ in tog(1)
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1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/queue.h>
18 
19 #include <errno.h>
20 #define _XOPEN_SOURCE_EXTENDED
21 #include <curses.h>
22 #undef _XOPEN_SOURCE_EXTENDED
23 #include <panel.h>
24 #include <locale.h>
25 #include <stdlib.h>
26 #include <stdio.h>
27 #include <getopt.h>
28 #include <string.h>
29 #include <err.h>
30 #include <unistd.h>
31 #include <util.h>
32 #include <limits.h>
33 #include <wchar.h>
34 
35 #include "got_error.h"
36 #include "got_object.h"
37 #include "got_reference.h"
38 #include "got_repository.h"
39 #include "got_diff.h"
40 #include "got_opentemp.h"
41 #include "got_commit_graph.h"
42 #include "got_utf8.h"
43 
44 #ifndef MIN
45 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
46 #endif
47 
48 #ifndef nitems
49 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
50 #endif
51 
52 struct tog_cmd {
53 	const char *name;
54 	const struct got_error *(*cmd_main)(int, char *[]);
55 	void (*cmd_usage)(void);
56 	const char *descr;
57 };
58 
59 __dead static void	usage(void);
60 __dead static void	usage_log(void);
61 __dead static void	usage_diff(void);
62 __dead static void	usage_blame(void);
63 
64 static const struct got_error*	cmd_log(int, char *[]);
65 static const struct got_error*	cmd_diff(int, char *[]);
66 static const struct got_error*	cmd_blame(int, char *[]);
67 
68 static struct tog_cmd tog_commands[] = {
69 	{ "log",	cmd_log,	usage_log,
70 	    "show repository history" },
71 	{ "diff",	cmd_diff,	usage_diff,
72 	    "compare files and directories" },
73 	{ "blame",	cmd_blame,	usage_blame,
74 	    "show line-by-line file history" },
75 };
76 
77 static struct tog_view {
78 	WINDOW *window;
79 	PANEL *panel;
80 } tog_log_view, tog_diff_view;
81 
82 static const struct got_error *
83 show_diff_view(struct got_object *, struct got_object *,
84     struct got_repository *);
85 static const struct got_error *
86 show_log_view(struct got_object_id *, struct got_repository *);
87 
88 __dead static void
89 usage_log(void)
90 {
91 	endwin();
92 	fprintf(stderr, "usage: %s log [-c commit] [repository-path]\n",
93 	    getprogname());
94 	exit(1);
95 }
96 
97 /* Create newly allocated wide-character string equivalent to a byte string. */
98 static const struct got_error *
99 mbs2ws(wchar_t **ws, size_t *wlen, const char *s)
100 {
101 	char *vis = NULL;
102 	const struct got_error *err = NULL;
103 
104 	*ws = NULL;
105 	*wlen = mbstowcs(NULL, s, 0);
106 	if (*wlen == (size_t)-1) {
107 		int vislen;
108 		if (errno != EILSEQ)
109 			return got_error_from_errno();
110 
111 		/* byte string invalid in current encoding; try to "fix" it */
112 		err = got_mbsavis(&vis, &vislen, s);
113 		if (err)
114 			return err;
115 		*wlen = mbstowcs(NULL, vis, 0);
116 		if (*wlen == (size_t)-1)
117 			return got_error_from_errno(); /* give up */
118 	}
119 
120 	*ws = calloc(*wlen + 1, sizeof(*ws));
121 	if (*ws == NULL)
122 		return got_error_from_errno();
123 
124 	if (mbstowcs(*ws, vis ? vis : s, *wlen) != *wlen)
125 		err = got_error_from_errno();
126 
127 	free(vis);
128 	if (err) {
129 		free(*ws);
130 		*ws = NULL;
131 		*wlen = 0;
132 	}
133 	return err;
134 }
135 
136 /* Format a line for display, ensuring that it won't overflow a width limit. */
137 static const struct got_error *
138 format_line(wchar_t **wlinep, int *widthp, char *line, int wlimit)
139 {
140 	const struct got_error *err = NULL;
141 	int cols = 0;
142 	wchar_t *wline = NULL;
143 	size_t wlen;
144 	int i;
145 
146 	*wlinep = NULL;
147 
148 	err = mbs2ws(&wline, &wlen, line);
149 	if (err)
150 		return err;
151 
152 	i = 0;
153 	while (i < wlen && cols <= wlimit) {
154 		int width = wcwidth(wline[i]);
155 		switch (width) {
156 		case 0:
157 			break;
158 		case 1:
159 		case 2:
160 			cols += width;
161 			break;
162 		case -1:
163 			if (wline[i] == L'\t')
164 				cols += TABSIZE;
165 			break;
166 		default:
167 			err = got_error_from_errno();
168 			goto done;
169 		}
170 		if (cols <= COLS) {
171 			i++;
172 			if (widthp)
173 				*widthp = cols;
174 		}
175 	}
176 	wline[i] = L'\0';
177 done:
178 	if (err)
179 		free(wline);
180 	else
181 		*wlinep = wline;
182 	return err;
183 }
184 
185 static const struct got_error *
186 draw_commit(struct got_commit_object *commit, struct got_object_id *id)
187 {
188 	const struct got_error *err = NULL;
189 	char *logmsg0 = NULL, *logmsg = NULL;
190 	char *author0 = NULL, *author = NULL;
191 	wchar_t *wlogmsg = NULL, *wauthor = NULL;
192 	int author_width, logmsg_width;
193 	char *newline, *smallerthan;
194 	char *line = NULL;
195 	char *id_str = NULL;
196 	size_t id_len;
197 	int col, limit;
198 	static const size_t id_display_cols = 8;
199 	static const size_t author_display_cols = 16;
200 	const int avail = COLS;
201 
202 	err = got_object_id_str(&id_str, id);
203 	if (err)
204 		return err;
205 	id_len = strlen(id_str);
206 	if (avail < id_display_cols) {
207 		limit = MIN(id_len, avail);
208 		waddnstr(tog_log_view.window, id_str, limit);
209 	} else {
210 		limit = MIN(id_display_cols, id_len);
211 		waddnstr(tog_log_view.window, id_str, limit);
212 	}
213 	col = limit + 1;
214 	while (col <= avail && col < id_display_cols + 2) {
215 		waddch(tog_log_view.window, ' ');
216 		col++;
217 	}
218 	if (col > avail)
219 		goto done;
220 
221 	author0 = strdup(commit->author);
222 	if (author0 == NULL) {
223 		err = got_error_from_errno();
224 		goto done;
225 	}
226 	author = author0;
227 	smallerthan = strchr(author, '<');
228 	if (smallerthan)
229 		*smallerthan = '\0';
230 	else {
231 		char *at = strchr(author, '@');
232 		if (at)
233 			*at = '\0';
234 	}
235 	limit = MIN(avail, author_display_cols);
236 	err = format_line(&wauthor, &author_width, author, limit);
237 	if (err)
238 		goto done;
239 	waddwstr(tog_log_view.window, wauthor);
240 	col += author_width;
241 	while (col <= avail && author_width < author_display_cols + 1) {
242 		waddch(tog_log_view.window, ' ');
243 		col++;
244 		author_width++;
245 	}
246 	if (col > avail)
247 		goto done;
248 
249 	logmsg0 = strdup(commit->logmsg);
250 	if (logmsg0 == NULL) {
251 		err = got_error_from_errno();
252 		goto done;
253 	}
254 	logmsg = logmsg0;
255 	while (*logmsg == '\n')
256 		logmsg++;
257 	newline = strchr(logmsg, '\n');
258 	if (newline)
259 		*newline = '\0';
260 	limit = avail - col;
261 	err = format_line(&wlogmsg, &logmsg_width, logmsg, limit);
262 	if (err)
263 		goto done;
264 	waddwstr(tog_log_view.window, wlogmsg);
265 	col += logmsg_width;
266 	while (col <= avail) {
267 		waddch(tog_log_view.window, ' ');
268 		col++;
269 	}
270 done:
271 	free(logmsg0);
272 	free(wlogmsg);
273 	free(author0);
274 	free(wauthor);
275 	free(line);
276 	free(id_str);
277 	return err;
278 }
279 
280 struct commit_queue_entry {
281 	TAILQ_ENTRY(commit_queue_entry) entry;
282 	struct got_object_id *id;
283 	struct got_commit_object *commit;
284 };
285 TAILQ_HEAD(commit_queue, commit_queue_entry);
286 
287 static struct commit_queue_entry *
288 alloc_commit_queue_entry(struct got_commit_object *commit,
289     struct got_object_id *id)
290 {
291 	struct commit_queue_entry *entry;
292 
293 	entry = calloc(1, sizeof(*entry));
294 	if (entry == NULL)
295 		return NULL;
296 
297 	entry->id = id;
298 	entry->commit = commit;
299 	return entry;
300 }
301 
302 static void
303 pop_commit(struct commit_queue *commits)
304 {
305 	struct commit_queue_entry *entry;
306 
307 	entry = TAILQ_FIRST(commits);
308 	TAILQ_REMOVE(commits, entry, entry);
309 	got_object_commit_close(entry->commit);
310 	/* Don't free entry->id! It is owned by the commit graph. */
311 	free(entry);
312 }
313 
314 static void
315 free_commits(struct commit_queue *commits)
316 {
317 	while (!TAILQ_EMPTY(commits))
318 		pop_commit(commits);
319 }
320 
321 static const struct got_error *
322 queue_commits(struct got_commit_graph *graph, struct commit_queue *commits,
323     struct got_object_id *start_id, struct got_repository *repo)
324 {
325 	const struct got_error *err = NULL;
326 	struct got_object_id *id;
327 	struct commit_queue_entry *entry;
328 
329 	err = got_commit_graph_iter_start(graph, start_id);
330 	if (err)
331 		return err;
332 
333 	entry = TAILQ_LAST(commits, commit_queue);
334 	if (entry && got_object_id_cmp(entry->id, start_id) == 0) {
335 		int nfetched;
336 
337 		/* Start ID's commit is already on the queue; skip over it. */
338 		err = got_commit_graph_iter_next(&id, graph);
339 		if (err && err->code != GOT_ERR_ITER_NEED_MORE)
340 			return err;
341 
342 		err = got_commit_graph_fetch_commits(&nfetched, graph, 1, repo);
343 		if (err)
344 			return err;
345 	}
346 
347 	while (1) {
348 		struct got_commit_object *commit;
349 
350 		err = got_commit_graph_iter_next(&id, graph);
351 		if (err) {
352 			if (err->code == GOT_ERR_ITER_NEED_MORE)
353 				err = NULL;
354 			break;
355 		}
356 
357 		err = got_object_open_as_commit(&commit, repo, id);
358 		if (err)
359 			break;
360 
361 		entry = alloc_commit_queue_entry(commit, id);
362 		if (entry == NULL) {
363 			err = got_error_from_errno();
364 			break;
365 		}
366 
367 		TAILQ_INSERT_TAIL(commits, entry, entry);
368 	}
369 
370 	return err;
371 }
372 
373 static const struct got_error *
374 fetch_next_commit(struct commit_queue_entry **pentry,
375     struct commit_queue_entry *entry, struct commit_queue *commits,
376     struct got_commit_graph *graph, struct got_repository *repo)
377 {
378 	const struct got_error *err = NULL;
379 	struct got_object_qid *qid;
380 
381 	*pentry = NULL;
382 
383 	/* Populate commit graph with entry's parent commits. */
384 	SIMPLEQ_FOREACH(qid, &entry->commit->parent_ids, entry) {
385 		int nfetched;
386 		err = got_commit_graph_fetch_commits_up_to(&nfetched,
387 			graph, qid->id, repo);
388 		if (err)
389 			return err;
390 	}
391 
392 	/* Append outstanding commits to queue in graph sort order. */
393 	err = queue_commits(graph, commits, entry->id, repo);
394 	if (err) {
395 		if (err->code == GOT_ERR_ITER_COMPLETED)
396 			err = NULL;
397 		return err;
398 	}
399 
400 	/* Next entry to display should now be available. */
401 	*pentry = TAILQ_NEXT(entry, entry);
402 	if (*pentry == NULL)
403 		return got_error(GOT_ERR_NO_OBJ);
404 
405 	return NULL;
406 }
407 
408 static const struct got_error *
409 get_head_commit_id(struct got_object_id **head_id, struct got_repository *repo)
410 {
411 	const struct got_error *err = NULL;
412 	struct got_reference *head_ref;
413 
414 	*head_id = NULL;
415 
416 	err = got_ref_open(&head_ref, repo, GOT_REF_HEAD);
417 	if (err)
418 		return err;
419 
420 	err = got_ref_resolve(head_id, repo, head_ref);
421 	got_ref_close(head_ref);
422 	if (err) {
423 		*head_id = NULL;
424 		return err;
425 	}
426 
427 	return NULL;
428 }
429 
430 static const struct got_error *
431 draw_commits(struct commit_queue_entry **last, struct commit_queue_entry **selected,
432     struct commit_queue_entry *first, int selected_idx, int limit)
433 {
434 	const struct got_error *err = NULL;
435 	struct commit_queue_entry *entry;
436 	int ncommits = 0;
437 
438 	werase(tog_log_view.window);
439 
440 	entry = first;
441 	*last = first;
442 	while (entry) {
443 		if (ncommits == limit)
444 			break;
445 		if (ncommits == selected_idx) {
446 			wstandout(tog_log_view.window);
447 			*selected = entry;
448 		}
449 		err = draw_commit(entry->commit, entry->id);
450 		if (ncommits == selected_idx)
451 			wstandend(tog_log_view.window);
452 		if (err)
453 			break;
454 		ncommits++;
455 		*last = entry;
456 		entry = TAILQ_NEXT(entry, entry);
457 	}
458 
459 	update_panels();
460 	doupdate();
461 
462 	return err;
463 }
464 
465 static void
466 scroll_up(struct commit_queue_entry **first_displayed_entry, int maxscroll,
467     struct commit_queue *commits)
468 {
469 	struct commit_queue_entry *entry;
470 	int nscrolled = 0;
471 
472 	entry = TAILQ_FIRST(commits);
473 	if (*first_displayed_entry == entry)
474 		return;
475 
476 	entry = *first_displayed_entry;
477 	while (entry && nscrolled < maxscroll) {
478 		entry = TAILQ_PREV(entry, commit_queue, entry);
479 		if (entry) {
480 			*first_displayed_entry = entry;
481 			nscrolled++;
482 		}
483 	}
484 }
485 
486 static const struct got_error *
487 scroll_down(struct commit_queue_entry **first_displayed_entry, int maxscroll,
488     struct commit_queue_entry *last_displayed_entry,
489     struct commit_queue *commits, struct got_commit_graph *graph,
490     struct got_repository *repo)
491 {
492 	const struct got_error *err = NULL;
493 	struct commit_queue_entry *pentry;
494 	int nscrolled = 0;
495 
496 	do {
497 		pentry = TAILQ_NEXT(last_displayed_entry, entry);
498 		if (pentry == NULL) {
499 			err = fetch_next_commit(&pentry, last_displayed_entry,
500 			    commits, graph, repo);
501 			if (err || pentry == NULL)
502 				break;
503 		}
504 		last_displayed_entry = pentry;
505 
506 		pentry = TAILQ_NEXT(*first_displayed_entry, entry);
507 		if (pentry == NULL)
508 			break;
509 		*first_displayed_entry = pentry;
510 	} while (++nscrolled < maxscroll);
511 
512 	return err;
513 }
514 
515 static int
516 num_parents(struct commit_queue_entry *entry)
517 {
518 	int nparents = 0;
519 
520 	while (entry) {
521 		entry = TAILQ_NEXT(entry, entry);
522 		nparents++;
523 	}
524 
525 	return nparents;
526 }
527 
528 static const struct got_error *
529 show_commit(struct commit_queue_entry *entry, struct got_repository *repo)
530 {
531 	const struct got_error *err;
532 	struct got_object *obj1 = NULL, *obj2 = NULL;
533 	struct got_object_qid *parent_id;
534 
535 	err = got_object_open(&obj2, repo, entry->id);
536 	if (err)
537 		return err;
538 
539 	parent_id = SIMPLEQ_FIRST(&entry->commit->parent_ids);
540 	if (parent_id) {
541 		err = got_object_open(&obj1, repo, parent_id->id);
542 		if (err)
543 			goto done;
544 	}
545 
546 	err = show_diff_view(obj1, obj2, repo);
547 done:
548 	if (obj1)
549 		got_object_close(obj1);
550 	if (obj2)
551 		got_object_close(obj2);
552 	return err;
553 }
554 
555 static const struct got_error *
556 show_log_view(struct got_object_id *start_id, struct got_repository *repo)
557 {
558 	const struct got_error *err = NULL;
559 	struct got_object_id *head_id = NULL;
560 	int ch, done = 0, selected = 0, nparents, nfetched;
561 	struct got_commit_graph *graph;
562 	struct commit_queue commits;
563 	struct commit_queue_entry *entry = NULL;
564 	struct commit_queue_entry *first_displayed_entry = NULL;
565 	struct commit_queue_entry *last_displayed_entry = NULL;
566 	struct commit_queue_entry *selected_entry = NULL;
567 
568 	if (tog_log_view.window == NULL) {
569 		tog_log_view.window = newwin(0, 0, 0, 0);
570 		if (tog_log_view.window == NULL)
571 			return got_error_from_errno();
572 		keypad(tog_log_view.window, TRUE);
573 	}
574 	if (tog_log_view.panel == NULL) {
575 		tog_log_view.panel = new_panel(tog_log_view.window);
576 		if (tog_log_view.panel == NULL)
577 			return got_error_from_errno();
578 	} else
579 		show_panel(tog_log_view.panel);
580 
581 	err = get_head_commit_id(&head_id, repo);
582 	if (err)
583 		return err;
584 
585 	TAILQ_INIT(&commits);
586 
587 	err = got_commit_graph_open(&graph, head_id, repo);
588 	if (err)
589 		goto done;
590 
591 	/* Populate commit graph with a sufficient number of commits. */
592 	err = got_commit_graph_fetch_commits_up_to(&nfetched, graph, start_id,
593 	    repo);
594 	if (err)
595 		goto done;
596 	err = got_commit_graph_fetch_commits(&nfetched, graph, LINES, repo);
597 	if (err)
598 		goto done;
599 
600 	/*
601 	 * Open the initial batch of commits, sorted in commit graph order.
602 	 * We keep all commits open throughout the lifetime of the log view
603 	 * in order to avoid having to re-fetch commits from disk while
604 	 * updating the display.
605 	 */
606 	err = queue_commits(graph, &commits, head_id, repo);
607 	if (err && err->code != GOT_ERR_ITER_COMPLETED)
608 		goto done;
609 
610 	/* Find entry corresponding to the first commit to display. */
611 	TAILQ_FOREACH(entry, &commits, entry) {
612 		if (got_object_id_cmp(entry->id, start_id) == 0) {
613 			first_displayed_entry = entry;
614 			break;
615 		}
616 	}
617 	if (first_displayed_entry == NULL) {
618 		err = got_error(GOT_ERR_NO_OBJ);
619 		goto done;
620 	}
621 
622 	while (!done) {
623 		err = draw_commits(&last_displayed_entry, &selected_entry,
624 		    first_displayed_entry, selected, LINES);
625 		if (err)
626 			goto done;
627 
628 		nodelay(stdscr, FALSE);
629 		ch = wgetch(tog_log_view.window);
630 		nodelay(stdscr, TRUE);
631 		switch (ch) {
632 			case ERR:
633 				if (errno) {
634 					err = got_error_from_errno();
635 					goto done;
636 				}
637 				break;
638 			case 'q':
639 				done = 1;
640 				break;
641 			case 'k':
642 			case KEY_UP:
643 				if (selected > 0)
644 					selected--;
645 				if (selected > 0)
646 					break;
647 				scroll_up(&first_displayed_entry, 1, &commits);
648 				break;
649 			case KEY_PPAGE:
650 				if (TAILQ_FIRST(&commits) ==
651 				    first_displayed_entry) {
652 					selected = 0;
653 					break;
654 				}
655 				scroll_up(&first_displayed_entry, LINES,
656 				    &commits);
657 				break;
658 			case 'j':
659 			case KEY_DOWN:
660 				nparents = num_parents(first_displayed_entry);
661 				if (selected < LINES - 1 &&
662 				    selected < nparents - 1) {
663 					selected++;
664 					break;
665 				}
666 				err = scroll_down(&first_displayed_entry, 1,
667 				    last_displayed_entry, &commits, graph,
668 				    repo);
669 				if (err)
670 					goto done;
671 				break;
672 			case KEY_NPAGE:
673 				err = scroll_down(&first_displayed_entry, LINES,
674 				    last_displayed_entry, &commits, graph,
675 				    repo);
676 				if (err)
677 					goto done;
678 				if (last_displayed_entry->commit->nparents > 0)
679 					break;
680 				/* can't scroll any further; move cursor down */
681 				nparents = num_parents(first_displayed_entry);
682 				if (selected < LINES - 1 ||
683 				    selected < nparents - 1)
684 					selected = MIN(LINES - 1, nparents - 1);
685 				break;
686 			case KEY_RESIZE:
687 				if (selected > LINES)
688 					selected = LINES - 1;
689 				break;
690 			case KEY_ENTER:
691 			case '\r':
692 				err = show_commit(selected_entry, repo);
693 				if (err)
694 					break;
695 				show_panel(tog_log_view.panel);
696 				break;
697 			default:
698 				break;
699 		}
700 	}
701 done:
702 	free(head_id);
703 	if (graph)
704 		got_commit_graph_close(graph);
705 	free_commits(&commits);
706 	return err;
707 }
708 
709 static const struct got_error *
710 cmd_log(int argc, char *argv[])
711 {
712 	const struct got_error *error;
713 	struct got_repository *repo;
714 	struct got_object_id *start_id = NULL;
715 	char *repo_path = NULL;
716 	char *start_commit = NULL;
717 	int ch;
718 
719 #ifndef PROFILE
720 	if (pledge("stdio rpath wpath cpath flock proc tty", NULL) == -1)
721 		err(1, "pledge");
722 #endif
723 
724 	while ((ch = getopt(argc, argv, "c:")) != -1) {
725 		switch (ch) {
726 		case 'c':
727 			start_commit = optarg;
728 			break;
729 		default:
730 			usage();
731 			/* NOTREACHED */
732 		}
733 	}
734 
735 	argc -= optind;
736 	argv += optind;
737 
738 	if (argc == 0) {
739 		repo_path = getcwd(NULL, 0);
740 		if (repo_path == NULL)
741 			return got_error_from_errno();
742 	} else if (argc == 1) {
743 		repo_path = realpath(argv[0], NULL);
744 		if (repo_path == NULL)
745 			return got_error_from_errno();
746 	} else
747 		usage_log();
748 
749 	error = got_repo_open(&repo, repo_path);
750 	free(repo_path);
751 	if (error != NULL)
752 		return error;
753 
754 	if (start_commit == NULL) {
755 		error = get_head_commit_id(&start_id, repo);
756 		if (error != NULL)
757 			return error;
758 	} else {
759 		struct got_object *obj;
760 		error = got_object_open_by_id_str(&obj, repo, start_commit);
761 		if (error == NULL) {
762 			start_id = got_object_get_id(obj);
763 			if (start_id == NULL)
764 				error = got_error_from_errno();
765 		}
766 	}
767 	if (error != NULL)
768 		return error;
769 	error = show_log_view(start_id, repo);
770 	free(start_id);
771 	got_repo_close(repo);
772 	return error;
773 }
774 
775 __dead static void
776 usage_diff(void)
777 {
778 	endwin();
779 	fprintf(stderr, "usage: %s diff [repository-path] object1 object2\n",
780 	    getprogname());
781 	exit(1);
782 }
783 
784 static char *
785 parse_next_line(FILE *f, size_t *len)
786 {
787 	char *line;
788 	size_t linelen;
789 	size_t lineno;
790 	const char delim[3] = { '\0', '\0', '\0'};
791 
792 	line = fparseln(f, &linelen, &lineno, delim, 0);
793 	if (len)
794 		*len = linelen;
795 	return line;
796 }
797 
798 static const struct got_error *
799 draw_diff(FILE *f, int *first_displayed_line, int *last_displayed_line,
800     int *eof, int max_lines)
801 {
802 	const struct got_error *err;
803 	int nlines = 0, nprinted = 0;
804 	char *line;
805 	size_t len;
806 	wchar_t *wline;
807 	int width;
808 
809 	rewind(f);
810 	werase(tog_diff_view.window);
811 
812 	*eof = 0;
813 	while (nprinted < max_lines) {
814 		line = parse_next_line(f, &len);
815 		if (line == NULL) {
816 			*eof = 1;
817 			break;
818 		}
819 		if (++nlines < *first_displayed_line) {
820 			free(line);
821 			continue;
822 		}
823 
824 		err = format_line(&wline, &width, line, COLS);
825 		if (err) {
826 			free(line);
827 			return err;
828 		}
829 		waddwstr(tog_diff_view.window, wline);
830 		if (width < COLS)
831 			waddch(tog_diff_view.window, '\n');
832 		if (++nprinted == 1)
833 			*first_displayed_line = nlines;
834 		free(line);
835 	}
836 	*last_displayed_line = nlines;
837 
838 	update_panels();
839 	doupdate();
840 
841 	return NULL;
842 }
843 
844 static const struct got_error *
845 show_diff_view(struct got_object *obj1, struct got_object *obj2,
846     struct got_repository *repo)
847 {
848 	const struct got_error *err;
849 	FILE *f;
850 	int ch, done = 0, first_displayed_line = 1, last_displayed_line = LINES;
851 	int eof, i;
852 
853 	if (obj1 != NULL && obj2 != NULL &&
854 	    got_object_get_type(obj1) != got_object_get_type(obj2))
855 		return got_error(GOT_ERR_OBJ_TYPE);
856 
857 	f = got_opentemp();
858 	if (f == NULL)
859 		return got_error_from_errno();
860 
861 	switch (got_object_get_type(obj1 ? obj1 : obj2)) {
862 	case GOT_OBJ_TYPE_BLOB:
863 		err = got_diff_objects_as_blobs(obj1, obj2, repo, f);
864 		break;
865 	case GOT_OBJ_TYPE_TREE:
866 		err = got_diff_objects_as_trees(obj1, obj2, repo, f);
867 		break;
868 	case GOT_OBJ_TYPE_COMMIT:
869 		err = got_diff_objects_as_commits(obj1, obj2, repo, f);
870 		break;
871 	default:
872 		return got_error(GOT_ERR_OBJ_TYPE);
873 	}
874 
875 	fflush(f);
876 
877 	if (tog_diff_view.window == NULL) {
878 		tog_diff_view.window = newwin(0, 0, 0, 0);
879 		if (tog_diff_view.window == NULL)
880 			return got_error_from_errno();
881 		keypad(tog_diff_view.window, TRUE);
882 	}
883 	if (tog_diff_view.panel == NULL) {
884 		tog_diff_view.panel = new_panel(tog_diff_view.window);
885 		if (tog_diff_view.panel == NULL)
886 			return got_error_from_errno();
887 	} else
888 		show_panel(tog_diff_view.panel);
889 
890 	while (!done) {
891 		err = draw_diff(f, &first_displayed_line, &last_displayed_line,
892 		    &eof, LINES);
893 		if (err)
894 			break;
895 		nodelay(stdscr, FALSE);
896 		ch = wgetch(tog_diff_view.window);
897 		nodelay(stdscr, TRUE);
898 		switch (ch) {
899 			case 'q':
900 				done = 1;
901 				break;
902 			case 'k':
903 			case KEY_UP:
904 			case KEY_BACKSPACE:
905 				if (first_displayed_line > 1)
906 					first_displayed_line--;
907 				break;
908 			case KEY_PPAGE:
909 				i = 0;
910 				while (i++ < LINES - 1 &&
911 				    first_displayed_line > 1)
912 					first_displayed_line--;
913 				break;
914 			case 'j':
915 			case KEY_DOWN:
916 			case KEY_ENTER:
917 			case '\r':
918 				if (!eof)
919 					first_displayed_line++;
920 				break;
921 			case KEY_NPAGE:
922 			case ' ':
923 				i = 0;
924 				while (!eof && i++ < LINES - 1) {
925 					char *line = parse_next_line(f, NULL);
926 					first_displayed_line++;
927 					if (line == NULL)
928 						break;
929 				}
930 				break;
931 			default:
932 				break;
933 		}
934 	}
935 	fclose(f);
936 	return err;
937 }
938 
939 static const struct got_error *
940 cmd_diff(int argc, char *argv[])
941 {
942 	const struct got_error *error = NULL;
943 	struct got_repository *repo = NULL;
944 	struct got_object *obj1 = NULL, *obj2 = NULL;
945 	char *repo_path = NULL;
946 	char *obj_id_str1 = NULL, *obj_id_str2 = NULL;
947 	int ch;
948 
949 #ifndef PROFILE
950 	if (pledge("stdio rpath wpath cpath flock proc tty", NULL) == -1)
951 		err(1, "pledge");
952 #endif
953 
954 	while ((ch = getopt(argc, argv, "")) != -1) {
955 		switch (ch) {
956 		default:
957 			usage();
958 			/* NOTREACHED */
959 		}
960 	}
961 
962 	argc -= optind;
963 	argv += optind;
964 
965 	if (argc == 0) {
966 		usage_diff(); /* TODO show local worktree changes */
967 	} else if (argc == 2) {
968 		repo_path = getcwd(NULL, 0);
969 		if (repo_path == NULL)
970 			return got_error_from_errno();
971 		obj_id_str1 = argv[0];
972 		obj_id_str2 = argv[1];
973 	} else if (argc == 3) {
974 		repo_path = realpath(argv[0], NULL);
975 		if (repo_path == NULL)
976 			return got_error_from_errno();
977 		obj_id_str1 = argv[1];
978 		obj_id_str2 = argv[2];
979 	} else
980 		usage_diff();
981 
982 	error = got_repo_open(&repo, repo_path);
983 	free(repo_path);
984 	if (error)
985 		goto done;
986 
987 	error = got_object_open_by_id_str(&obj1, repo, obj_id_str1);
988 	if (error)
989 		goto done;
990 
991 	error = got_object_open_by_id_str(&obj2, repo, obj_id_str2);
992 	if (error)
993 		goto done;
994 
995 	error = show_diff_view(obj1, obj2, repo);
996 done:
997 	got_repo_close(repo);
998 	if (obj1)
999 		got_object_close(obj1);
1000 	if (obj2)
1001 		got_object_close(obj2);
1002 	return error;
1003 }
1004 
1005 __dead static void
1006 usage_blame(void)
1007 {
1008 	endwin();
1009 	fprintf(stderr, "usage: %s blame [repository-path] blob-object\n",
1010 	    getprogname());
1011 	exit(1);
1012 }
1013 
1014 static const struct got_error *
1015 cmd_blame(int argc, char *argv[])
1016 {
1017 	return got_error(GOT_ERR_NOT_IMPL);
1018 }
1019 
1020 static void
1021 init_curses(void)
1022 {
1023 	initscr();
1024 	cbreak();
1025 	noecho();
1026 	nonl();
1027 	intrflush(stdscr, FALSE);
1028 	keypad(stdscr, TRUE);
1029 	curs_set(0);
1030 }
1031 
1032 __dead static void
1033 usage(void)
1034 {
1035 	int i;
1036 
1037 	fprintf(stderr, "usage: %s [-h] [command] [arg ...]\n\n"
1038 	    "Available commands:\n", getprogname());
1039 	for (i = 0; i < nitems(tog_commands); i++) {
1040 		struct tog_cmd *cmd = &tog_commands[i];
1041 		fprintf(stderr, "    %s: %s\n", cmd->name, cmd->descr);
1042 	}
1043 	exit(1);
1044 }
1045 
1046 static char **
1047 make_argv(const char *arg0, const char *arg1)
1048 {
1049 	char **argv;
1050 	int argc = (arg1 == NULL ? 1 : 2);
1051 
1052 	argv = calloc(argc, sizeof(char *));
1053 	if (argv == NULL)
1054 		err(1, "calloc");
1055 	argv[0] = strdup(arg0);
1056 	if (argv[0] == NULL)
1057 		err(1, "calloc");
1058 	if (arg1) {
1059 		argv[1] = strdup(arg1);
1060 		if (argv[1] == NULL)
1061 			err(1, "calloc");
1062 	}
1063 
1064 	return argv;
1065 }
1066 
1067 int
1068 main(int argc, char *argv[])
1069 {
1070 	const struct got_error *error = NULL;
1071 	struct tog_cmd *cmd = NULL;
1072 	int ch, hflag = 0;
1073 	char **cmd_argv = NULL;
1074 
1075 	setlocale(LC_ALL, "");
1076 
1077 	while ((ch = getopt(argc, argv, "h")) != -1) {
1078 		switch (ch) {
1079 		case 'h':
1080 			hflag = 1;
1081 			break;
1082 		default:
1083 			usage();
1084 			/* NOTREACHED */
1085 		}
1086 	}
1087 
1088 	argc -= optind;
1089 	argv += optind;
1090 	optind = 0;
1091 	optreset = 1;
1092 
1093 	if (argc == 0) {
1094 		/* Build an argument vector which runs a default command. */
1095 		cmd = &tog_commands[0];
1096 		cmd_argv = make_argv(cmd->name, NULL);
1097 		argc = 1;
1098 	} else {
1099 		int i;
1100 
1101 		/* Did the user specific a command? */
1102 		for (i = 0; i < nitems(tog_commands); i++) {
1103 			if (strncmp(tog_commands[i].name, argv[0],
1104 			    strlen(argv[0])) == 0) {
1105 				cmd = &tog_commands[i];
1106 				if (hflag)
1107 					tog_commands[i].cmd_usage();
1108 				break;
1109 			}
1110 		}
1111 		if (cmd == NULL) {
1112 			/* Did the user specify a repository? */
1113 			char *repo_path = realpath(argv[0], NULL);
1114 			if (repo_path) {
1115 				struct got_repository *repo;
1116 				error = got_repo_open(&repo, repo_path);
1117 				if (error == NULL)
1118 					got_repo_close(repo);
1119 			} else
1120 				error = got_error_from_errno();
1121 			if (error) {
1122 				fprintf(stderr, "%s: '%s' is neither a known "
1123 				    "command nor a path to a repository\n",
1124 				    getprogname(), argv[0]);
1125 				free(repo_path);
1126 				return 1;
1127 			}
1128 			cmd = &tog_commands[0];
1129 			cmd_argv = make_argv(cmd->name, repo_path);
1130 			argc = 2;
1131 			free(repo_path);
1132 		}
1133 	}
1134 
1135 	init_curses();
1136 
1137 	error = cmd->cmd_main(argc, cmd_argv ? cmd_argv : argv);
1138 	if (error)
1139 		goto done;
1140 done:
1141 	endwin();
1142 	free(cmd_argv);
1143 	if (error)
1144 		fprintf(stderr, "%s: %s\n", getprogname(), error->msg);
1145 	return 0;
1146 }