xref: /openbsd-src/usr.bin/tmux/layout-custom.c (revision fe1f7dfa9438a02ac3cf846b995d81cf559db7f5)
1 /* $OpenBSD: layout-custom.c,v 1.14 2019/06/15 06:33:48 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;
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 	/* Resize to the layout size. */
157 	window_resize(w, lc->sx, lc->sy);
158 
159 	/* Destroy the old layout and swap to the new. */
160 	layout_free_cell(w->layout_root);
161 	w->layout_root = lc;
162 
163 	/* Assign the panes into the cells. */
164 	wp = TAILQ_FIRST(&w->panes);
165 	layout_assign(&wp, lc);
166 
167 	/* Update pane offsets and sizes. */
168 	layout_fix_offsets(lc);
169 	layout_fix_panes(w);
170 	recalculate_sizes();
171 
172 	layout_print_cell(lc, __func__, 0);
173 
174 	notify_window("window-layout-changed", w);
175 
176 	return (0);
177 
178 fail:
179 	layout_free_cell(lc);
180 	return (-1);
181 }
182 
183 /* Assign panes into cells. */
184 static void
185 layout_assign(struct window_pane **wp, struct layout_cell *lc)
186 {
187 	struct layout_cell	*lcchild;
188 
189 	switch (lc->type) {
190 	case LAYOUT_WINDOWPANE:
191 		layout_make_leaf(lc, *wp);
192 		*wp = TAILQ_NEXT(*wp, entry);
193 		return;
194 	case LAYOUT_LEFTRIGHT:
195 	case LAYOUT_TOPBOTTOM:
196 		TAILQ_FOREACH(lcchild, &lc->cells, entry)
197 			layout_assign(wp, lcchild);
198 		return;
199 	}
200 }
201 
202 /* Construct a cell from all or part of a layout tree. */
203 static struct layout_cell *
204 layout_construct(struct layout_cell *lcparent, const char **layout)
205 {
206 	struct layout_cell     *lc, *lcchild;
207 	u_int			sx, sy, xoff, yoff;
208 	const char	       *saved;
209 
210 	if (!isdigit((u_char) **layout))
211 		return (NULL);
212 	if (sscanf(*layout, "%ux%u,%u,%u", &sx, &sy, &xoff, &yoff) != 4)
213 		return (NULL);
214 
215 	while (isdigit((u_char) **layout))
216 		(*layout)++;
217 	if (**layout != 'x')
218 		return (NULL);
219 	(*layout)++;
220 	while (isdigit((u_char) **layout))
221 		(*layout)++;
222 	if (**layout != ',')
223 		return (NULL);
224 	(*layout)++;
225 	while (isdigit((u_char) **layout))
226 		(*layout)++;
227 	if (**layout != ',')
228 		return (NULL);
229 	(*layout)++;
230 	while (isdigit((u_char) **layout))
231 		(*layout)++;
232 	if (**layout == ',') {
233 		saved = *layout;
234 		(*layout)++;
235 		while (isdigit((u_char) **layout))
236 			(*layout)++;
237 		if (**layout == 'x')
238 			*layout = saved;
239 	}
240 
241 	lc = layout_create_cell(lcparent);
242 	lc->sx = sx;
243 	lc->sy = sy;
244 	lc->xoff = xoff;
245 	lc->yoff = yoff;
246 
247 	switch (**layout) {
248 	case ',':
249 	case '}':
250 	case ']':
251 	case '\0':
252 		return (lc);
253 	case '{':
254 		lc->type = LAYOUT_LEFTRIGHT;
255 		break;
256 	case '[':
257 		lc->type = LAYOUT_TOPBOTTOM;
258 		break;
259 	default:
260 		goto fail;
261 	}
262 
263 	do {
264 		(*layout)++;
265 		lcchild = layout_construct(lc, layout);
266 		if (lcchild == NULL)
267 			goto fail;
268 		TAILQ_INSERT_TAIL(&lc->cells, lcchild, entry);
269 	} while (**layout == ',');
270 
271 	switch (lc->type) {
272 	case LAYOUT_LEFTRIGHT:
273 		if (**layout != '}')
274 			goto fail;
275 		break;
276 	case LAYOUT_TOPBOTTOM:
277 		if (**layout != ']')
278 			goto fail;
279 		break;
280 	default:
281 		goto fail;
282 	}
283 	(*layout)++;
284 
285 	return (lc);
286 
287 fail:
288 	layout_free_cell(lc);
289 	return (NULL);
290 }
291