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