Blame


1 65d9b3ca 2021-03-14 op /*
2 65d9b3ca 2021-03-14 op * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3 65d9b3ca 2021-03-14 op *
4 65d9b3ca 2021-03-14 op * Permission to use, copy, modify, and distribute this software for any
5 65d9b3ca 2021-03-14 op * purpose with or without fee is hereby granted, provided that the above
6 65d9b3ca 2021-03-14 op * copyright notice and this permission notice appear in all copies.
7 65d9b3ca 2021-03-14 op *
8 65d9b3ca 2021-03-14 op * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 65d9b3ca 2021-03-14 op * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 65d9b3ca 2021-03-14 op * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 65d9b3ca 2021-03-14 op * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 65d9b3ca 2021-03-14 op * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 65d9b3ca 2021-03-14 op * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 65d9b3ca 2021-03-14 op * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 65d9b3ca 2021-03-14 op */
16 65d9b3ca 2021-03-14 op
17 65d9b3ca 2021-03-14 op #include <stdlib.h>
18 65d9b3ca 2021-03-14 op #include <string.h>
19 65d9b3ca 2021-03-14 op
20 88693f61 2021-07-15 op #include "defaults.h"
21 5caf7d67 2021-07-12 op #include "telescope.h"
22 5caf7d67 2021-07-12 op #include "utf8.h"
23 5caf7d67 2021-07-12 op
24 65d9b3ca 2021-03-14 op /*
25 65d9b3ca 2021-03-14 op * Text wrapping
26 65d9b3ca 2021-03-14 op * =============
27 65d9b3ca 2021-03-14 op *
28 65d9b3ca 2021-03-14 op * There's a simple text wrapping algorithm.
29 65d9b3ca 2021-03-14 op *
30 65d9b3ca 2021-03-14 op * 1. if it's a line in a pre-formatted block:
31 65d9b3ca 2021-03-14 op * a. hard wrap.
32 65d9b3ca 2021-03-14 op * b. repeat
33 676fba6f 2021-03-21 op * 2. otherwise advance the line char by char.
34 676fba6f 2021-03-21 op * 3. when ending the space, split the line at the last occurrence of
35 676fba6f 2021-03-21 op * a "word separator" (i.e. " \t-") or at point if none.
36 65d9b3ca 2021-03-14 op * 4. repeat
37 65d9b3ca 2021-03-14 op *
38 65d9b3ca 2021-03-14 op */
39 65d9b3ca 2021-03-14 op
40 ca5da938 2021-04-01 op void
41 bca92a4c 2021-07-01 op erase_buffer(struct buffer *buffer)
42 bca92a4c 2021-07-01 op {
43 bca92a4c 2021-07-01 op empty_vlist(buffer);
44 bca92a4c 2021-07-01 op empty_linelist(buffer);
45 bca92a4c 2021-07-01 op }
46 bca92a4c 2021-07-01 op
47 bca92a4c 2021-07-01 op void
48 46f6e974 2021-05-17 op empty_linelist(struct buffer *buffer)
49 ca5da938 2021-04-01 op {
50 ca5da938 2021-04-01 op struct line *l, *lt;
51 ca5da938 2021-04-01 op
52 46f6e974 2021-05-17 op TAILQ_FOREACH_SAFE(l, &buffer->page.head, lines, lt) {
53 46f6e974 2021-05-17 op TAILQ_REMOVE(&buffer->page.head, l, lines);
54 ca5da938 2021-04-01 op free(l->line);
55 fbadd395 2021-07-16 op free(l->alt);
56 ca5da938 2021-04-01 op free(l);
57 ca5da938 2021-04-01 op }
58 ca5da938 2021-04-01 op }
59 ca5da938 2021-04-01 op
60 ca5da938 2021-04-01 op void
61 46f6e974 2021-05-17 op empty_vlist(struct buffer *buffer)
62 ca5da938 2021-04-01 op {
63 ca5da938 2021-04-01 op struct vline *vl, *t;
64 ca5da938 2021-04-01 op
65 4ea9160a 2021-07-01 op buffer->top_line = NULL;
66 4ea9160a 2021-07-01 op buffer->line_off = 0;
67 46f6e974 2021-05-17 op buffer->current_line = NULL;
68 46f6e974 2021-05-17 op buffer->line_max = 0;
69 ca5da938 2021-04-01 op
70 46f6e974 2021-05-17 op TAILQ_FOREACH_SAFE(vl, &buffer->head, vlines, t) {
71 46f6e974 2021-05-17 op TAILQ_REMOVE(&buffer->head, vl, vlines);
72 ca5da938 2021-04-01 op free(vl->line);
73 ca5da938 2021-04-01 op free(vl);
74 ca5da938 2021-04-01 op }
75 ca5da938 2021-04-01 op }
76 ca5da938 2021-04-01 op
77 65d9b3ca 2021-03-14 op static int
78 87f7918d 2021-07-14 op push_line(struct buffer *buffer, struct line *l, const char *buf, size_t len, int flags)
79 65d9b3ca 2021-03-14 op {
80 65d9b3ca 2021-03-14 op struct vline *vl;
81 65d9b3ca 2021-03-14 op
82 6e6c6afb 2021-07-14 op if (!(l->flags & L_HIDDEN))
83 6e6c6afb 2021-07-14 op buffer->line_max++;
84 65d9b3ca 2021-03-14 op
85 65d9b3ca 2021-03-14 op if ((vl = calloc(1, sizeof(*vl))) == NULL)
86 65d9b3ca 2021-03-14 op return 0;
87 65d9b3ca 2021-03-14 op
88 65d9b3ca 2021-03-14 op if (len != 0 && (vl->line = calloc(1, len+1)) == NULL) {
89 65d9b3ca 2021-03-14 op free(vl);
90 65d9b3ca 2021-03-14 op return 0;
91 65d9b3ca 2021-03-14 op }
92 65d9b3ca 2021-03-14 op
93 65d9b3ca 2021-03-14 op vl->parent = l;
94 65d9b3ca 2021-03-14 op if (len != 0)
95 65d9b3ca 2021-03-14 op memcpy(vl->line, buf, len);
96 5492b68f 2021-07-05 op vl->flags = flags;
97 65d9b3ca 2021-03-14 op
98 46f6e974 2021-05-17 op if (TAILQ_EMPTY(&buffer->head))
99 46f6e974 2021-05-17 op TAILQ_INSERT_HEAD(&buffer->head, vl, vlines);
100 65d9b3ca 2021-03-14 op else
101 46f6e974 2021-05-17 op TAILQ_INSERT_TAIL(&buffer->head, vl, vlines);
102 65d9b3ca 2021-03-14 op return 1;
103 65d9b3ca 2021-03-14 op }
104 65d9b3ca 2021-03-14 op
105 65d9b3ca 2021-03-14 op /*
106 e7b982f4 2021-07-14 op * Similar to wrap_text, but emit only o vline.
107 e7b982f4 2021-07-14 op */
108 e7b982f4 2021-07-14 op int
109 e7b982f4 2021-07-14 op wrap_one(struct buffer *buffer, const char *prfx, struct line *l, size_t width)
110 e7b982f4 2021-07-14 op {
111 e7b982f4 2021-07-14 op struct vline *vl, *t;
112 e7b982f4 2021-07-14 op
113 e7b982f4 2021-07-14 op /*
114 e7b982f4 2021-07-14 op * be lazy: call wrap_text and then discard the continuations.
115 e7b982f4 2021-07-14 op */
116 e7b982f4 2021-07-14 op
117 e7b982f4 2021-07-14 op if (!wrap_text(buffer, prfx, l, width))
118 e7b982f4 2021-07-14 op return 0;
119 e7b982f4 2021-07-14 op
120 e7b982f4 2021-07-14 op TAILQ_FOREACH_SAFE(vl, &buffer->head, vlines, t) {
121 e7b982f4 2021-07-14 op if (vl->flags & L_CONTINUATION) {
122 e7b982f4 2021-07-14 op TAILQ_REMOVE(&buffer->head, vl, vlines);
123 e7b982f4 2021-07-14 op free(vl->line);
124 e7b982f4 2021-07-14 op free(vl);
125 6eddfe3c 2021-07-15 op buffer->line_max--;
126 e7b982f4 2021-07-14 op }
127 e7b982f4 2021-07-14 op }
128 e7b982f4 2021-07-14 op
129 e7b982f4 2021-07-14 op return 1;
130 e7b982f4 2021-07-14 op }
131 e7b982f4 2021-07-14 op
132 e7b982f4 2021-07-14 op /*
133 65d9b3ca 2021-03-14 op * Build a list of visual line by wrapping the given line, assuming
134 65d9b3ca 2021-03-14 op * that when printed will have a leading prefix prfx.
135 65d9b3ca 2021-03-14 op */
136 676fba6f 2021-03-21 op int
137 46f6e974 2021-05-17 op wrap_text(struct buffer *buffer, const char *prfx, struct line *l, size_t width)
138 65d9b3ca 2021-03-14 op {
139 676fba6f 2021-03-21 op const char *separators = " \t-";
140 676fba6f 2021-03-21 op const char *start, *end, *line, *lastsep, *lastchar;
141 676fba6f 2021-03-21 op uint32_t cp = 0, state = 0;
142 676fba6f 2021-03-21 op size_t cur, prfxwidth, w;
143 5492b68f 2021-07-05 op int flags;
144 65d9b3ca 2021-03-14 op
145 676fba6f 2021-03-21 op if ((line = l->line) == NULL)
146 46f6e974 2021-05-17 op return push_line(buffer, l, NULL, 0, 0);
147 65d9b3ca 2021-03-14 op
148 676fba6f 2021-03-21 op prfxwidth = utf8_swidth(prfx);
149 676fba6f 2021-03-21 op cur = prfxwidth;
150 676fba6f 2021-03-21 op start = line;
151 676fba6f 2021-03-21 op lastsep = NULL;
152 676fba6f 2021-03-21 op lastchar = line;
153 5492b68f 2021-07-05 op flags = 0;
154 676fba6f 2021-03-21 op for (; *line; line++) {
155 676fba6f 2021-03-21 op if (utf8_decode(&state, &cp, *line))
156 676fba6f 2021-03-21 op continue;
157 676fba6f 2021-03-21 op w = utf8_chwidth(cp);
158 676fba6f 2021-03-21 op if (cur + w >= width -1) {
159 676fba6f 2021-03-21 op end = lastsep == NULL
160 676fba6f 2021-03-21 op ? utf8_next_cp((char*)lastchar)
161 676fba6f 2021-03-21 op : utf8_next_cp((char*)lastsep);
162 5492b68f 2021-07-05 op if (!push_line(buffer, l, start, end - start, flags))
163 676fba6f 2021-03-21 op return 0;
164 963c680c 2021-07-05 op flags = L_CONTINUATION;
165 676fba6f 2021-03-21 op start = end;
166 676fba6f 2021-03-21 op cur = prfxwidth + utf8_swidth_between(start, lastchar);
167 5b010818 2021-07-05 op } else if (strchr(separators, *line) != NULL) {
168 5b010818 2021-07-05 op lastsep = line;
169 65d9b3ca 2021-03-14 op }
170 65d9b3ca 2021-03-14 op
171 676fba6f 2021-03-21 op lastchar = utf8_prev_cp(line, l->line);
172 676fba6f 2021-03-21 op cur += w;
173 65d9b3ca 2021-03-14 op }
174 65d9b3ca 2021-03-14 op
175 5492b68f 2021-07-05 op return push_line(buffer, l, start, line - start, flags);
176 65d9b3ca 2021-03-14 op }
177 65d9b3ca 2021-03-14 op
178 65d9b3ca 2021-03-14 op int
179 46f6e974 2021-05-17 op hardwrap_text(struct buffer *buffer, struct line *l, size_t width)
180 65d9b3ca 2021-03-14 op {
181 676fba6f 2021-03-21 op const char *line, *start, *lastchar;
182 65d9b3ca 2021-03-14 op int cont;
183 676fba6f 2021-03-21 op uint32_t state = 0, cp = 0;
184 676fba6f 2021-03-21 op size_t cur, w;
185 65d9b3ca 2021-03-14 op
186 676fba6f 2021-03-21 op if ((line = l->line) == NULL)
187 46f6e974 2021-05-17 op return push_line(buffer, l, NULL, 0, 0);
188 166712b4 2021-03-14 op
189 676fba6f 2021-03-21 op start = line;
190 676fba6f 2021-03-21 op lastchar = line;
191 676fba6f 2021-03-21 op cont = 0;
192 676fba6f 2021-03-21 op cur = 0;
193 676fba6f 2021-03-21 op for (; *line; line++) {
194 676fba6f 2021-03-21 op if (utf8_decode(&state, &cp, *line))
195 676fba6f 2021-03-21 op continue;
196 676fba6f 2021-03-21 op w = utf8_chwidth(cp);
197 676fba6f 2021-03-21 op if (cur + w >= width) {
198 46f6e974 2021-05-17 op if (!push_line(buffer, l, start, lastchar - start, cont))
199 676fba6f 2021-03-21 op return 0;
200 88693f61 2021-07-15 op cont = L_CONTINUATION;
201 88693f61 2021-07-15 op if (dont_wrap_pre)
202 88693f61 2021-07-15 op return 1;
203 676fba6f 2021-03-21 op cur = 0;
204 676fba6f 2021-03-21 op start = lastchar;
205 676fba6f 2021-03-21 op }
206 65d9b3ca 2021-03-14 op
207 676fba6f 2021-03-21 op lastchar = utf8_prev_cp(line, l->line);
208 676fba6f 2021-03-21 op cur += w;
209 65d9b3ca 2021-03-14 op }
210 65d9b3ca 2021-03-14 op
211 46f6e974 2021-05-17 op return push_line(buffer, l, start, line - start, cont);
212 65d9b3ca 2021-03-14 op }