1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
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 "compat.h"
18 
19 #include <errno.h>
20 #include <limits.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <time.h>
25 #include <unistd.h>
26 
27 #include "defaults.h"
28 #include "fs.h"
29 #include "minibuffer.h"
30 #include "session.h"
31 #include "ui.h"
32 
33 struct history	history;
34 
35 static struct event	 autosaveev;
36 
37 void
38 switch_to_tab(struct tab *tab)
39 {
40 	current_tab = tab;
41 	tab->flags &= ~TAB_URGENT;
42 
43 	if (operating && tab->flags & TAB_LAZY)
44 		load_url_in_tab(tab, tab->hist_cur->h, NULL, LU_MODE_NOHIST);
45 }
46 
47 unsigned int
48 tab_new_id(void)
49 {
50 	static uint32_t tab_counter;
51 
52 	return tab_counter++;
53 }
54 
55 struct tab *
56 new_tab(const char *url, const char *base, struct tab *after)
57 {
58 	struct tab	*tab;
59 
60 	ui_schedule_redraw();
61 	autosave_hook();
62 
63 	if ((tab = calloc(1, sizeof(*tab))) == NULL) {
64 		event_loopbreak();
65 		return NULL;
66 	}
67 
68 	TAILQ_INIT(&tab->hist.head);
69 	TAILQ_INIT(&tab->buffer.head);
70 	TAILQ_INIT(&tab->buffer.page.head);
71 	evtimer_set(&tab->loadingev, NULL, NULL);
72 
73 	tab->id = tab_new_id();
74 
75 	if (after != NULL)
76 		TAILQ_INSERT_AFTER(&tabshead, after, tab, tabs);
77 	else
78 		TAILQ_INSERT_TAIL(&tabshead, tab, tabs);
79 
80 	if (!operating)
81 		tab->flags |= TAB_LAZY;
82 	load_url_in_tab(tab, url, base, 0);
83 	switch_to_tab(tab);
84 	return tab;
85 }
86 
87 /*
88  * Move a tab from the tablist to the killed tab list and erase its
89  * contents.  Append should always be 0 to prepend tabs so unkill_tab
90  * can work correctly; appending is only useful during startup when
91  * receiving the list of killed tabs to keep the correct order.
92  * NB: doesn't update the current_tab.
93  */
94 void
95 kill_tab(struct tab *tab, int append)
96 {
97 	int count;
98 
99 	stop_tab(tab);
100 	erase_buffer(&tab->buffer);
101 	TAILQ_REMOVE(&tabshead, tab, tabs);
102 	ui_schedule_redraw();
103 	autosave_hook();
104 
105 	if (evtimer_pending(&tab->loadingev, NULL))
106 		evtimer_del(&tab->loadingev);
107 
108 	if (append)
109 		TAILQ_INSERT_TAIL(&ktabshead, tab, tabs);
110 	else
111 		TAILQ_INSERT_HEAD(&ktabshead, tab, tabs);
112 
113 	/* gc closed tabs */
114 	count = 0;
115 	TAILQ_FOREACH(tab, &ktabshead, tabs)
116 		count++;
117 	while (count > max_killed_tabs) {
118 		count--;
119 		free_tab(TAILQ_LAST(&ktabshead, tabshead));
120 	}
121 }
122 
123 /*
124  * Resurrects the lastest killed tab and returns it.  The tab is already
125  * added to the tab list with the TAB_LAZY flag set.  NB: this doesn't
126  * update current_tab.
127  */
128 struct tab *
129 unkill_tab(void)
130 {
131 	struct tab *t;
132 
133 	if (TAILQ_EMPTY(&ktabshead))
134 		return NULL;
135 
136 	ui_schedule_redraw();
137 	autosave_hook();
138 
139 	t = TAILQ_FIRST(&ktabshead);
140 	TAILQ_REMOVE(&ktabshead, t, tabs);
141 	TAILQ_INSERT_TAIL(&tabshead, t, tabs);
142 	t->flags |= TAB_LAZY;
143 	return t;
144 }
145 
146 /*
147  * Free every resource linked to the tab, including the tab itself, and
148  * removes it from the *killed* tablist.
149  */
150 void
151 free_tab(struct tab *tab)
152 {
153 	TAILQ_REMOVE(&ktabshead, tab, tabs);
154 	hist_clear(&tab->hist);
155 	free(tab);
156 }
157 
158 void
159 stop_tab(struct tab *tab)
160 {
161 	ui_send_net(IMSG_STOP, tab->id, NULL, 0);
162 }
163 
164 static inline void
165 savetab(FILE *fp, struct tab *tab, int killed)
166 {
167 	struct hist	*h;
168 	size_t		 top_line, current_line;
169 	int		 future;
170 
171 	get_scroll_position(tab, &top_line, &current_line);
172 
173 	fprintf(fp, "%s ", tab->hist_cur->h);
174 	if (tab == current_tab)
175 		fprintf(fp, "current,");
176 	if (killed)
177 		fprintf(fp, "killed,");
178 
179 	fprintf(fp, "top=%zu,cur=%zu %s\n", top_line, current_line,
180 	    tab->buffer.page.title);
181 
182 	future = 0;
183 	TAILQ_FOREACH(h, &tab->hist.head, entries) {
184 		if (h == tab->hist_cur) {
185 			future = 1;
186 			continue;
187 		}
188 
189 		fprintf(fp, "%s %s\n", future ? ">" : "<", h->h);
190 	}
191 }
192 
193 void
194 save_session(void)
195 {
196 	FILE		*tmp;
197 	struct tab	*tab;
198 	size_t		 i;
199 	int		 fd, err=  0;
200 	char		 sfn[PATH_MAX];
201 
202 	if (safe_mode)
203 		return;
204 
205 	strlcpy(sfn, session_file_tmp, sizeof(sfn));
206 	if ((fd = mkstemp(sfn)) == -1 ||
207 	    (tmp = fdopen(fd, "w")) == NULL) {
208 		if (fd != -1) {
209 			unlink(sfn);
210 			close(fd);
211 		}
212 		return;
213 	}
214 
215 	TAILQ_FOREACH(tab, &tabshead, tabs)
216 		savetab(tmp, tab, 0);
217 	TAILQ_FOREACH(tab, &ktabshead, tabs)
218 		savetab(tmp, tab, 1);
219 
220 	err = ferror(tmp);
221 	fclose(tmp);
222 
223 	if (err) {
224 		unlink(sfn);
225 		return;
226 	}
227 
228 	if (rename(sfn, session_file))
229 		return;
230 
231 	strlcpy(sfn, history_file_tmp, sizeof(sfn));
232 	if ((fd = mkstemp(sfn)) == -1 ||
233 	    (tmp = fdopen(fd, "w")) == NULL) {
234 		if (fd != -1) {
235 			unlink(sfn);
236 			close(fd);
237 		}
238 		return;
239 	}
240 
241 	if (history.dirty) {
242 		for (i = 0; i < history.len && history.dirty > 0; ++i) {
243 			if (!history.items[i].dirty)
244 				continue;
245 			history.dirty--;
246 			history.items[i].dirty = 0;
247 
248 			fprintf(tmp, "%lld %s\n",
249 			    (long long)history.items[i].ts,
250 			    history.items[i].uri);
251 		}
252 		history.dirty = 0;
253 	}
254 
255 	err = ferror(tmp);
256 	fclose(tmp);
257 
258 	if (err) {
259 		unlink(sfn);
260 		return;
261 	}
262 
263 	rename(sfn, history_file);
264 }
265 
266 void
267 history_push(struct histitem *hi)
268 {
269 	size_t		 i, oldest = 0;
270 	char		*uri;
271 
272 	for (i = 0; i < history.len; ++i) {
273 		if (history.items[i].ts < history.items[oldest].ts)
274 			oldest = i;
275 
276 		/* remove duplicates */
277 		if (!strcmp(history.items[i].uri, hi->uri))
278 			return;
279 	}
280 
281 	if ((uri = strdup(hi->uri)) == NULL)
282 		abort();
283 
284 	/* don't grow too much; replace the oldest */
285 	if (history.len == HISTORY_CAP) {
286 		history.items[oldest].ts = hi->ts;
287 		free(history.items[oldest].uri);
288 		history.items[oldest].uri = uri;
289 		return;
290 	}
291 
292 	history.items[history.len].ts = hi->ts;
293 	history.items[history.len].uri = uri;
294 	history.len++;
295 }
296 
297 static int
298 history_cmp(const void *a, const void *b)
299 {
300 	const struct history_item *i = a, *j = b;
301 	return strcmp(i->uri, j->uri);
302 }
303 
304 void
305 history_sort(void)
306 {
307 	qsort(history.items, history.len, sizeof(history.items[0]),
308 	    history_cmp);
309 }
310 
311 void
312 history_add(const char *uri)
313 {
314 	size_t	 i, j, insert = 0, oldest = 0;
315 	char	*u;
316 	int	 c;
317 
318 	for (i = 0; i < history.len; ++i) {
319 		if (history.items[i].ts < history.items[oldest].ts)
320 			oldest = i;
321 
322 		if (insert != 0 && insert < i)
323 			continue;
324 
325 		c = strcmp(uri, history.items[i].uri);
326 		if (c == 0) {
327 			history.items[i].ts = time(NULL);
328 			history.items[i].dirty = 1;
329 			history.dirty++;
330 			autosave_hook();
331 			return;
332 		}
333 
334 		if (c > 0)
335 			insert = i;
336 	}
337 
338 	if ((u = strdup(uri)) == NULL)
339 		return;
340 
341 	/* if history is full, replace the oldest one */
342 	if (history.len == HISTORY_CAP) {
343 		free(history.items[oldest].uri);
344 		history.items[oldest].uri = u;
345 		history.items[oldest].ts = time(NULL);
346 		history.items[oldest].dirty = 1;
347 		history.dirty++;
348 		history_sort();
349 		autosave_hook();
350 		return;
351 	}
352 
353 	/* otherwise just insert in the right spot */
354 
355 	for (j = history.len; j > insert; --j)
356 		memcpy(&history.items[j], &history.items[j-1],
357 		    sizeof(history.items[j]));
358 
359 	history.items[insert].ts = time(NULL);
360 	history.items[insert].uri = u;
361 	history.items[insert].dirty = 1;
362 	history.dirty++;
363 	history.len++;
364 	autosave_hook();
365 }
366 
367 void
368 autosave_init(void)
369 {
370 	evtimer_set(&autosaveev, autosave_timer, NULL);
371 }
372 
373 void
374 autosave_timer(int fd, short event, void *data)
375 {
376 	save_session();
377 }
378 
379 /*
380  * Function to be called in "interesting" places where we may want to
381  * schedule an autosave (like on new tab or before loading an url.)
382  */
383 void
384 autosave_hook(void)
385 {
386 	struct timeval tv;
387 
388 	if (autosave <= 0)
389 		return;
390 
391 	if (!evtimer_pending(&autosaveev, NULL)) {
392 		tv.tv_sec = autosave;
393 		tv.tv_usec = 0;
394 
395 		evtimer_add(&autosaveev, &tv);
396 	}
397 }