xref: /openbsd-src/usr.bin/tmux/layout-custom.c (revision 8e1abdf8a8ed897046e3a8488250ad3c39dd6ab3)
1 /* $OpenBSD: layout-custom.c,v 1.13 2019/06/12 08:08:33 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 
21 #include <ctype.h>
22 #include <string.h>
23 
24 #include "tmux.h"
25 
26 static struct layout_cell	*layout_find_bottomright(struct layout_cell *);
27 static u_short			 layout_checksum(const char *);
28 static int			 layout_append(struct layout_cell *, char *,
29 				     size_t);
30 static struct layout_cell	*layout_construct(struct layout_cell *,
31 				     const char **);
32 static void			 layout_assign(struct window_pane **,
33 				     struct layout_cell *);
34 
35 /* Find the bottom-right cell. */
36 static struct layout_cell *
37 layout_find_bottomright(struct layout_cell *lc)
38 {
39 	if (lc->type == LAYOUT_WINDOWPANE)
40 		return (lc);
41 	lc = TAILQ_LAST(&lc->cells, layout_cells);
42 	return (layout_find_bottomright(lc));
43 }
44 
45 /* Calculate layout checksum. */
46 static u_short
47 layout_checksum(const char *layout)
48 {
49 	u_short	csum;
50 
51 	csum = 0;
52 	for (; *layout != '\0'; layout++) {
53 		csum = (csum >> 1) + ((csum & 1) << 15);
54 		csum += *layout;
55 	}
56 	return (csum);
57 }
58 
59 /* Dump layout as a string. */
60 char *
61 layout_dump(struct layout_cell *root)
62 {
63 	char	layout[BUFSIZ], *out;
64 
65 	*layout = '\0';
66 	if (layout_append(root, layout, sizeof layout) != 0)
67 		return (NULL);
68 
69 	xasprintf(&out, "%04hx,%s", layout_checksum(layout), layout);
70 	return (out);
71 }
72 
73 /* Append information for a single cell. */
74 static int
75 layout_append(struct layout_cell *lc, char *buf, size_t len)
76 {
77 	struct layout_cell     *lcchild;
78 	char			tmp[64];
79 	size_t			tmplen;
80 	const char	       *brackets = "][";
81 
82 	if (len == 0)
83 		return (-1);
84 
85 	if (lc->wp != NULL) {
86 		tmplen = xsnprintf(tmp, sizeof tmp, "%ux%u,%u,%u,%u",
87 		    lc->sx, lc->sy, lc->xoff, lc->yoff, lc->wp->id);
88 	} else {
89 		tmplen = xsnprintf(tmp, sizeof tmp, "%ux%u,%u,%u",
90 		    lc->sx, lc->sy, lc->xoff, lc->yoff);
91 	}
92 	if (tmplen > (sizeof tmp) - 1)
93 		return (-1);
94 	if (strlcat(buf, tmp, len) >= len)
95 		return (-1);
96 
97 	switch (lc->type) {
98 	case LAYOUT_LEFTRIGHT:
99 		brackets = "}{";
100 		/* FALLTHROUGH */
101 	case LAYOUT_TOPBOTTOM:
102 		if (strlcat(buf, &brackets[1], len) >= len)
103 			return (-1);
104 		TAILQ_FOREACH(lcchild, &lc->cells, entry) {
105 			if (layout_append(lcchild, buf, len) != 0)
106 				return (-1);
107 			if (strlcat(buf, ",", len) >= len)
108 				return (-1);
109 		}
110 		buf[strlen(buf) - 1] = brackets[0];
111 		break;
112 	case LAYOUT_WINDOWPANE:
113 		break;
114 	}
115 
116 	return (0);
117 }
118 
119 /* Parse a layout string and arrange window as layout. */
120 int
121 layout_parse(struct window *w, const char *layout)
122 {
123 	struct layout_cell	*lc, *lcchild;
124 	struct window_pane	*wp;
125 	u_int			 npanes, ncells, sx, sy;
126 	u_short			 csum;
127 
128 	/* Check validity. */
129 	if (sscanf(layout, "%hx,", &csum) != 1)
130 		return (-1);
131 	layout += 5;
132 	if (csum != layout_checksum(layout))
133 		return (-1);
134 
135 	/* Build the layout. */
136 	lc = layout_construct(NULL, &layout);
137 	if (lc == NULL)
138 		return (-1);
139 	if (*layout != '\0')
140 		goto fail;
141 
142 	/* Check this window will fit into the layout. */
143 	for (;;) {
144 		npanes = window_count_panes(w);
145 		ncells = layout_count_cells(lc);
146 		if (npanes > ncells)
147 			goto fail;
148 		if (npanes == ncells)
149 			break;
150 
151 		/* Fewer panes than cells - close the bottom right. */
152 		lcchild = layout_find_bottomright(lc);
153 		layout_destroy_cell(w, lcchild, &lc);
154 	}
155 
156 	/* Save the old window size and resize to the layout size. */
157 	sx = w->sx; sy = w->sy;
158 	window_resize(w, lc->sx, lc->sy);
159 
160 	/* Destroy the old layout and swap to the new. */
161 	layout_free_cell(w->layout_root);
162 	w->layout_root = lc;
163 
164 	/* Assign the panes into the cells. */
165 	wp = TAILQ_FIRST(&w->panes);
166 	layout_assign(&wp, lc);
167 
168 	/* Update pane offsets and sizes. */
169 	layout_fix_offsets(lc);
170 	layout_fix_panes(w);
171 	recalculate_sizes();
172 
173 	layout_print_cell(lc, __func__, 0);
174 
175 	notify_window("window-layout-changed", w);
176 
177 	return (0);
178 
179 fail:
180 	layout_free_cell(lc);
181 	return (-1);
182 }
183 
184 /* Assign panes into cells. */
185 static void
186 layout_assign(struct window_pane **wp, struct layout_cell *lc)
187 {
188 	struct layout_cell	*lcchild;
189 
190 	switch (lc->type) {
191 	case LAYOUT_WINDOWPANE:
192 		layout_make_leaf(lc, *wp);
193 		*wp = TAILQ_NEXT(*wp, entry);
194 		return;
195 	case LAYOUT_LEFTRIGHT:
196 	case LAYOUT_TOPBOTTOM:
197 		TAILQ_FOREACH(lcchild, &lc->cells, entry)
198 			layout_assign(wp, lcchild);
199 		return;
200 	}
201 }
202 
203 /* Construct a cell from all or part of a layout tree. */
204 static struct layout_cell *
205 layout_construct(struct layout_cell *lcparent, const char **layout)
206 {
207 	struct layout_cell     *lc, *lcchild;
208 	u_int			sx, sy, xoff, yoff;
209 	const char	       *saved;
210 
211 	if (!isdigit((u_char) **layout))
212 		return (NULL);
213 	if (sscanf(*layout, "%ux%u,%u,%u", &sx, &sy, &xoff, &yoff) != 4)
214 		return (NULL);
215 
216 	while (isdigit((u_char) **layout))
217 		(*layout)++;
218 	if (**layout != 'x')
219 		return (NULL);
220 	(*layout)++;
221 	while (isdigit((u_char) **layout))
222 		(*layout)++;
223 	if (**layout != ',')
224 		return (NULL);
225 	(*layout)++;
226 	while (isdigit((u_char) **layout))
227 		(*layout)++;
228 	if (**layout != ',')
229 		return (NULL);
230 	(*layout)++;
231 	while (isdigit((u_char) **layout))
232 		(*layout)++;
233 	if (**layout == ',') {
234 		saved = *layout;
235 		(*layout)++;
236 		while (isdigit((u_char) **layout))
237 			(*layout)++;
238 		if (**layout == 'x')
239 			*layout = saved;
240 	}
241 
242 	lc = layout_create_cell(lcparent);
243 	lc->sx = sx;
244 	lc->sy = sy;
245 	lc->xoff = xoff;
246 	lc->yoff = yoff;
247 
248 	switch (**layout) {
249 	case ',':
250 	case '}':
251 	case ']':
252 	case '\0':
253 		return (lc);
254 	case '{':
255 		lc->type = LAYOUT_LEFTRIGHT;
256 		break;
257 	case '[':
258 		lc->type = LAYOUT_TOPBOTTOM;
259 		break;
260 	default:
261 		goto fail;
262 	}
263 
264 	do {
265 		(*layout)++;
266 		lcchild = layout_construct(lc, layout);
267 		if (lcchild == NULL)
268 			goto fail;
269 		TAILQ_INSERT_TAIL(&lc->cells, lcchild, entry);
270 	} while (**layout == ',');
271 
272 	switch (lc->type) {
273 	case LAYOUT_LEFTRIGHT:
274 		if (**layout != '}')
275 			goto fail;
276 		break;
277 	case LAYOUT_TOPBOTTOM:
278 		if (**layout != ']')
279 			goto fail;
280 		break;
281 	default:
282 		goto fail;
283 	}
284 	(*layout)++;
285 
286 	return (lc);
287 
288 fail:
289 	layout_free_cell(lc);
290 	return (NULL);
291 }
292