1 /*-
2 * Copyright (c) 2009 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Ed Schouten under sponsorship from the
6 * FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD: stable/10/sys/dev/vt/vt_font.c 331983 2018-04-04 05:26:33Z gordon $");
32
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/refcount.h>
37 #include <sys/systm.h>
38
39 #include <dev/vt/vt.h>
40
41 static MALLOC_DEFINE(M_VTFONT, "vtfont", "vt font");
42
43 /* Some limits to prevent abnormal fonts from being loaded. */
44 #define VTFONT_MAXMAPPINGS 65536
45 #define VTFONT_MAXGLYPHS 131072
46 #define VTFONT_MAXGLYPHSIZE 2097152
47 #define VTFONT_MAXDIMENSION 128
48
49 static uint16_t
vtfont_bisearch(const struct vt_font_map * map,unsigned int len,uint32_t src)50 vtfont_bisearch(const struct vt_font_map *map, unsigned int len, uint32_t src)
51 {
52 int min, mid, max;
53
54 min = 0;
55 max = len - 1;
56
57 /* Empty font map. */
58 if (len == 0)
59 return (0);
60 /* Character below minimal entry. */
61 if (src < map[0].vfm_src)
62 return (0);
63 /* Optimization: ASCII characters occur very often. */
64 if (src <= map[0].vfm_src + map[0].vfm_len)
65 return (src - map[0].vfm_src + map[0].vfm_dst);
66 /* Character above maximum entry. */
67 if (src > map[max].vfm_src + map[max].vfm_len)
68 return (0);
69
70 /* Binary search. */
71 while (max >= min) {
72 mid = (min + max) / 2;
73 if (src < map[mid].vfm_src)
74 max = mid - 1;
75 else if (src > map[mid].vfm_src + map[mid].vfm_len)
76 min = mid + 1;
77 else
78 return (src - map[mid].vfm_src + map[mid].vfm_dst);
79 }
80
81 return (0);
82 }
83
84 const uint8_t *
vtfont_lookup(const struct vt_font * vf,term_char_t c)85 vtfont_lookup(const struct vt_font *vf, term_char_t c)
86 {
87 uint32_t src;
88 uint16_t dst;
89 size_t stride;
90 unsigned int normal_map;
91 unsigned int bold_map;
92
93 /*
94 * No support for printing right hand sides for CJK fullwidth
95 * characters. Simply print a space and assume that the left
96 * hand side describes the entire character.
97 */
98 src = TCHAR_CHARACTER(c);
99 if (TCHAR_FORMAT(c) & TF_CJK_RIGHT) {
100 normal_map = VFNT_MAP_NORMAL_RIGHT;
101 bold_map = VFNT_MAP_BOLD_RIGHT;
102 } else {
103 normal_map = VFNT_MAP_NORMAL;
104 bold_map = VFNT_MAP_BOLD;
105 }
106
107 if (TCHAR_FORMAT(c) & TF_BOLD) {
108 dst = vtfont_bisearch(vf->vf_map[bold_map],
109 vf->vf_map_count[bold_map], src);
110 if (dst != 0)
111 goto found;
112 }
113 dst = vtfont_bisearch(vf->vf_map[normal_map],
114 vf->vf_map_count[normal_map], src);
115
116 found:
117 stride = howmany(vf->vf_width, 8) * vf->vf_height;
118 return (&vf->vf_bytes[dst * stride]);
119 }
120
121 struct vt_font *
vtfont_ref(struct vt_font * vf)122 vtfont_ref(struct vt_font *vf)
123 {
124
125 refcount_acquire(&vf->vf_refcount);
126 return (vf);
127 }
128
129 void
vtfont_unref(struct vt_font * vf)130 vtfont_unref(struct vt_font *vf)
131 {
132 unsigned int i;
133
134 if (refcount_release(&vf->vf_refcount)) {
135 for (i = 0; i < VFNT_MAPS; i++)
136 free(vf->vf_map[i], M_VTFONT);
137 free(vf->vf_bytes, M_VTFONT);
138 free(vf, M_VTFONT);
139 }
140 }
141
142 static int
vtfont_validate_map(struct vt_font_map * vfm,unsigned int length,unsigned int glyph_count)143 vtfont_validate_map(struct vt_font_map *vfm, unsigned int length,
144 unsigned int glyph_count)
145 {
146 unsigned int i, last = 0;
147
148 for (i = 0; i < length; i++) {
149 /* Not ordered. */
150 if (i > 0 && vfm[i].vfm_src <= last)
151 return (EINVAL);
152 /*
153 * Destination extends amount of glyphs.
154 */
155 if (vfm[i].vfm_dst >= glyph_count ||
156 vfm[i].vfm_dst + vfm[i].vfm_len >= glyph_count)
157 return (EINVAL);
158 last = vfm[i].vfm_src + vfm[i].vfm_len;
159 }
160
161 return (0);
162 }
163
164 int
vtfont_load(vfnt_t * f,struct vt_font ** ret)165 vtfont_load(vfnt_t *f, struct vt_font **ret)
166 {
167 size_t glyphsize, mapsize;
168 struct vt_font *vf;
169 int error;
170 unsigned int i;
171
172 /* Make sure the dimensions are valid. */
173 if (f->width < 1 || f->height < 1)
174 return (EINVAL);
175 if (f->width > VTFONT_MAXDIMENSION || f->height > VTFONT_MAXDIMENSION ||
176 f->glyph_count > VTFONT_MAXGLYPHS)
177 return (E2BIG);
178
179 /* Not too many mappings. */
180 for (i = 0; i < VFNT_MAPS; i++)
181 if (f->map_count[i] > VTFONT_MAXMAPPINGS)
182 return (E2BIG);
183
184 /* Character 0 must always be present. */
185 if (f->glyph_count < 1)
186 return (EINVAL);
187
188 glyphsize = howmany(f->width, 8) * f->height * f->glyph_count;
189 if (glyphsize > VTFONT_MAXGLYPHSIZE)
190 return (E2BIG);
191
192 /* Allocate new font structure. */
193 vf = malloc(sizeof *vf, M_VTFONT, M_WAITOK | M_ZERO);
194 vf->vf_bytes = malloc(glyphsize, M_VTFONT, M_WAITOK);
195 vf->vf_height = f->height;
196 vf->vf_width = f->width;
197 vf->vf_refcount = 1;
198
199 /* Allocate, copy in, and validate mappings. */
200 for (i = 0; i < VFNT_MAPS; i++) {
201 vf->vf_map_count[i] = f->map_count[i];
202 if (f->map_count[i] == 0)
203 continue;
204 mapsize = f->map_count[i] * sizeof(struct vt_font_map);
205 vf->vf_map[i] = malloc(mapsize, M_VTFONT, M_WAITOK);
206 error = copyin(f->map[i], vf->vf_map[i], mapsize);
207 if (error)
208 goto bad;
209 error = vtfont_validate_map(vf->vf_map[i], vf->vf_map_count[i],
210 f->glyph_count);
211 if (error)
212 goto bad;
213 }
214
215 /* Copy in glyph data. */
216 error = copyin(f->glyphs, vf->vf_bytes, glyphsize);
217 if (error)
218 goto bad;
219
220 /* Success. */
221 *ret = vf;
222 return (0);
223
224 bad: vtfont_unref(vf);
225 return (error);
226 }
227