1/* vi: set sw=4 ts=4: */
2/*
3 * loadfont.c - Eugene Crosser & Andries Brouwer
4 *
5 * Version 0.96bb
6 *
7 * Loads the console font, and possibly the corresponding screen map(s).
8 * (Adapted for busybox by Matej Vela.)
9 */
10#include "libbb.h"
11#include <sys/kd.h>
12
13enum {
14	PSF_MAGIC1 = 0x36,
15	PSF_MAGIC2 = 0x04,
16
17	PSF_MODE512 = 0x01,
18	PSF_MODEHASTAB = 0x02,
19	PSF_MAXMODE = 0x03,
20	PSF_SEPARATOR = 0xFFFF
21};
22
23struct psf_header {
24	unsigned char magic1, magic2;   /* Magic number */
25	unsigned char mode;             /* PSF font mode */
26	unsigned char charsize;         /* Character size */
27};
28
29#define PSF_MAGIC_OK(x)	((x).magic1 == PSF_MAGIC1 && (x).magic2 == PSF_MAGIC2)
30
31static void do_loadfont(int fd, unsigned char *inbuf, int unit, int fontsize)
32{
33	char *buf;
34	int i;
35
36	if (unit < 1 || unit > 32)
37		bb_error_msg_and_die("bad character size %d", unit);
38
39	buf = xzalloc(16 * 1024);
40	/*memset(buf, 0, 16 * 1024);*/
41	for (i = 0; i < fontsize; i++)
42		memcpy(buf + (32 * i), inbuf + (unit * i), unit);
43
44#if defined(PIO_FONTX) && !defined(__sparc__)
45	{
46		struct consolefontdesc cfd;
47
48		cfd.charcount = fontsize;
49		cfd.charheight = unit;
50		cfd.chardata = buf;
51
52		if (!ioctl_or_perror(fd, PIO_FONTX, &cfd, "PIO_FONTX ioctl failed (will try PIO_FONT)"))
53			goto ret;			/* success */
54	}
55#endif
56	xioctl(fd, PIO_FONT, buf);
57 ret:
58	free(buf);
59}
60
61static void
62do_loadtable(int fd, unsigned char *inbuf, int tailsz, int fontsize)
63{
64	struct unimapinit advice;
65	struct unimapdesc ud;
66	struct unipair *up;
67	int ct = 0, maxct;
68	int glyph;
69	uint16_t unicode;
70
71	maxct = tailsz;				/* more than enough */
72	up = xmalloc(maxct * sizeof(struct unipair));
73
74	for (glyph = 0; glyph < fontsize; glyph++) {
75		while (tailsz >= 2) {
76			unicode = (((uint16_t) inbuf[1]) << 8) + inbuf[0];
77			tailsz -= 2;
78			inbuf += 2;
79			if (unicode == PSF_SEPARATOR)
80				break;
81			up[ct].unicode = unicode;
82			up[ct].fontpos = glyph;
83			ct++;
84		}
85	}
86
87	/* Note: after PIO_UNIMAPCLR and before PIO_UNIMAP
88	   this printf did not work on many kernels */
89
90	advice.advised_hashsize = 0;
91	advice.advised_hashstep = 0;
92	advice.advised_hashlevel = 0;
93	xioctl(fd, PIO_UNIMAPCLR, &advice);
94	ud.entry_ct = ct;
95	ud.entries = up;
96	xioctl(fd, PIO_UNIMAP, &ud);
97}
98
99static void loadnewfont(int fd)
100{
101	enum { INBUF_SIZE = 32*1024 + 1 };
102
103	int unit;
104	unsigned inputlth, offset;
105	/* Was on stack, but 32k is a bit too much: */
106	unsigned char *inbuf = xmalloc(INBUF_SIZE);
107
108	/*
109	 * We used to look at the length of the input file
110	 * with stat(); now that we accept compressed files,
111	 * just read the entire file.
112	 */
113	inputlth = full_read(STDIN_FILENO, inbuf, INBUF_SIZE);
114	if (inputlth < 0)
115		bb_perror_msg_and_die("error reading input font");
116	if (inputlth >= INBUF_SIZE)
117		bb_error_msg_and_die("font too large");
118
119	/* test for psf first */
120	{
121		struct psf_header psfhdr;
122		int fontsize;
123		int hastable;
124		unsigned head0, head;
125
126		if (inputlth < sizeof(struct psf_header))
127			goto no_psf;
128
129		psfhdr = *(struct psf_header *) &inbuf[0];
130
131		if (!PSF_MAGIC_OK(psfhdr))
132			goto no_psf;
133
134		if (psfhdr.mode > PSF_MAXMODE)
135			bb_error_msg_and_die("unsupported psf file mode");
136		fontsize = ((psfhdr.mode & PSF_MODE512) ? 512 : 256);
137#if !defined(PIO_FONTX) || defined(__sparc__)
138		if (fontsize != 256)
139			bb_error_msg_and_die("only fontsize 256 supported");
140#endif
141		hastable = (psfhdr.mode & PSF_MODEHASTAB);
142		unit = psfhdr.charsize;
143		head0 = sizeof(struct psf_header);
144
145		head = head0 + fontsize * unit;
146		if (head > inputlth || (!hastable && head != inputlth))
147			bb_error_msg_and_die("input file: bad length");
148		do_loadfont(fd, inbuf + head0, unit, fontsize);
149		if (hastable)
150			do_loadtable(fd, inbuf + head, inputlth - head, fontsize);
151		return;
152	}
153
154 no_psf:
155	/* file with three code pages? */
156	if (inputlth == 9780) {
157		offset = 40;
158		unit = 16;
159	} else {
160		/* bare font */
161		if (inputlth & 0377)
162			bb_error_msg_and_die("bad input file size");
163		offset = 0;
164		unit = inputlth / 256;
165	}
166	do_loadfont(fd, inbuf + offset, unit, 256);
167}
168
169int loadfont_main(int argc, char **argv);
170int loadfont_main(int argc, char **argv)
171{
172	int fd;
173
174	if (argc != 1)
175		bb_show_usage();
176
177	fd = xopen(CURRENT_VC, O_RDWR);
178	loadnewfont(fd);
179
180	return EXIT_SUCCESS;
181}
182