summaryrefslogtreecommitdiffhomepage
path: root/console-tools/loadfont.c
blob: 843f4b035b0821c162227241d6c419ba8369251f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
/* vi: set sw=4 ts=4: */
/*
 * loadfont.c - Eugene Crosser & Andries Brouwer
 *
 * Version 0.96bb
 *
 * Loads the console font, and possibly the corresponding screen map(s).
 * (Adapted for busybox by Matej Vela.)
 */
#include "libbb.h"
#include <sys/kd.h>

enum {
	PSF_MAGIC1 = 0x36,
	PSF_MAGIC2 = 0x04,

	PSF_MODE512 = 0x01,
	PSF_MODEHASTAB = 0x02,
	PSF_MAXMODE = 0x03,
	PSF_SEPARATOR = 0xFFFF
};

struct psf_header {
	unsigned char magic1, magic2;   /* Magic number */
	unsigned char mode;             /* PSF font mode */
	unsigned char charsize;         /* Character size */
};

#define PSF_MAGIC_OK(x)	((x).magic1 == PSF_MAGIC1 && (x).magic2 == PSF_MAGIC2)

static void do_loadfont(int fd, unsigned char *inbuf, int unit, int fontsize)
{
	char *buf;
	int i;

	if (unit < 1 || unit > 32)
		bb_error_msg_and_die("bad character size %d", unit);

	buf = xzalloc(16 * 1024);
	/*memset(buf, 0, 16 * 1024);*/
	for (i = 0; i < fontsize; i++)
		memcpy(buf + (32 * i), inbuf + (unit * i), unit);

#if defined(PIO_FONTX) && !defined(__sparc__)
	{
		struct consolefontdesc cfd;

		cfd.charcount = fontsize;
		cfd.charheight = unit;
		cfd.chardata = buf;

		if (!ioctl_or_perror(fd, PIO_FONTX, &cfd, "PIO_FONTX ioctl failed (will try PIO_FONT)"))
			goto ret;			/* success */
	}
#endif
	xioctl(fd, PIO_FONT, buf);
 ret:
	free(buf);
}

static void
do_loadtable(int fd, unsigned char *inbuf, int tailsz, int fontsize)
{
	struct unimapinit advice;
	struct unimapdesc ud;
	struct unipair *up;
	int ct = 0, maxct;
	int glyph;
	uint16_t unicode;

	maxct = tailsz;				/* more than enough */
	up = xmalloc(maxct * sizeof(struct unipair));

	for (glyph = 0; glyph < fontsize; glyph++) {
		while (tailsz >= 2) {
			unicode = (((uint16_t) inbuf[1]) << 8) + inbuf[0];
			tailsz -= 2;
			inbuf += 2;
			if (unicode == PSF_SEPARATOR)
				break;
			up[ct].unicode = unicode;
			up[ct].fontpos = glyph;
			ct++;
		}
	}

	/* Note: after PIO_UNIMAPCLR and before PIO_UNIMAP
	   this printf did not work on many kernels */

	advice.advised_hashsize = 0;
	advice.advised_hashstep = 0;
	advice.advised_hashlevel = 0;
	xioctl(fd, PIO_UNIMAPCLR, &advice);
	ud.entry_ct = ct;
	ud.entries = up;
	xioctl(fd, PIO_UNIMAP, &ud);
}

static void loadnewfont(int fd)
{
	enum { INBUF_SIZE = 32*1024 + 1 };

	int unit;
	unsigned inputlth, offset;
	/* Was on stack, but 32k is a bit too much: */
	unsigned char *inbuf = xmalloc(INBUF_SIZE);

	/*
	 * We used to look at the length of the input file
	 * with stat(); now that we accept compressed files,
	 * just read the entire file.
	 */
	inputlth = full_read(STDIN_FILENO, inbuf, INBUF_SIZE);
	if (inputlth < 0)
		bb_perror_msg_and_die("error reading input font");
	if (inputlth >= INBUF_SIZE)
		bb_error_msg_and_die("font too large");

	/* test for psf first */
	{
		struct psf_header psfhdr;
		int fontsize;
		int hastable;
		unsigned head0, head;

		if (inputlth < sizeof(struct psf_header))
			goto no_psf;

		psfhdr = *(struct psf_header *) &inbuf[0];

		if (!PSF_MAGIC_OK(psfhdr))
			goto no_psf;

		if (psfhdr.mode > PSF_MAXMODE)
			bb_error_msg_and_die("unsupported psf file mode");
		fontsize = ((psfhdr.mode & PSF_MODE512) ? 512 : 256);
#if !defined(PIO_FONTX) || defined(__sparc__)
		if (fontsize != 256)
			bb_error_msg_and_die("only fontsize 256 supported");
#endif
		hastable = (psfhdr.mode & PSF_MODEHASTAB);
		unit = psfhdr.charsize;
		head0 = sizeof(struct psf_header);

		head = head0 + fontsize * unit;
		if (head > inputlth || (!hastable && head != inputlth))
			bb_error_msg_and_die("input file: bad length");
		do_loadfont(fd, inbuf + head0, unit, fontsize);
		if (hastable)
			do_loadtable(fd, inbuf + head, inputlth - head, fontsize);
		return;
	}

 no_psf:
	/* file with three code pages? */
	if (inputlth == 9780) {
		offset = 40;
		unit = 16;
	} else {
		/* bare font */
		if (inputlth & 0377)
			bb_error_msg_and_die("bad input file size");
		offset = 0;
		unit = inputlth / 256;
	}
	do_loadfont(fd, inbuf + offset, unit, 256);
}

int loadfont_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int loadfont_main(int argc, char **argv ATTRIBUTE_UNUSED)
{
	int fd;

	if (argc != 1)
		bb_show_usage();

	fd = xopen(CURRENT_VC, O_RDWR);
	loadnewfont(fd);

	return EXIT_SUCCESS;
}