a crude BDF font loader for wsdisplay


(macallan)

PROG = bdfload
SRCS = bdfload.c

.include <bsd.prog.mk>

This will attempt to load a .bdf font into wsdisplay, to be used with
wsconsctl -dw font=<name>
Caveats:
- fonts wider than 16 pixels won't work yet
- the program does not distinguish between monospace and proportional fonts,
  and terminal output is necessarily monospace. Proportional fonts should
  work but the glyphs will be left justified in the character cell so things
  will look uneven.
- some drivers may have trouble with font widths that are not a multiple of 4
- no attempt has been made to make this play nice with vga text mode

/*	$NetBSD: bdfload.c,v 1.1 2019/01/02 22:05:24 macallan Exp $	*/

/*
 * Copyright (c) 2018 Michael Lorenz
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * a crude BDF loader for wsdisplay
 */

#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include <sys/ioctl.h>
#include <err.h>

#include <dev/wscons/wsconsio.h>

void
interpret(FILE *foo)
{
	char line[128], *arg, name[64] = "foop", *buffer, buflen = -1;
	int len, in_char = 0, current = -1, stride = 0, charsize = 0;
	int width, height, x, y, num;
	int first = 255, last = 0;
	int left, top, lines;
	int bl = 255, bt = 255, br = -1, bb = -1;
	struct wsdisplay_font f;
	int fdev;

	while (fgets(line, sizeof(line), foo) != NULL) {
		int i = 0;
		/* separate keyword from parameters */
		len = strlen(line);
		while (!isspace(line[i]) && (i < len)) i++;
		line[i] = 0;
		arg = &line[i + 1];
		i = 0;
		len = strlen(arg);
		/* get rid of garbage */
		while ((!iscntrl(arg[i])) && (arg[i] != 0)) {
			i++;
		}
		arg[i] = 0;
		if (strcmp(line, "FAMILY_NAME") == 0) {
			/* cut off quotation marks */
			strncpy(name, arg + 1, 64);
			name[strlen(name) - 1] = 0;
			printf("name: %s\n", name);
		} else if (strcmp(line, "FONTBOUNDINGBOX") == 0) {
			int res;
			res = sscanf(arg, "%d %d %d %d",
					  &width, &height, &x, &y);
			stride = (width + 7) >> 3;
			printf("box %d x %d\n", width, height);
			if (stride > 2) {
				printf("no fonts wider than 16 work for now\n");
				exit(1);
			}
			charsize = height * stride;
			buflen = 256 * charsize;
			buffer = malloc(buflen);
			if (buffer == NULL) {
				printf("failed to allocate %dKB for glyphs\n",
				    buflen);
				exit(1);
			} 
		} else if (strcmp(line, "CHARS") == 0) {
			if (sscanf(arg, "%d", &num) == 1)
				printf("number of characters: %d\n", num);
		} else if (strcmp(line, "STARTCHAR") == 0) {
			in_char = 1;
		} else if (strcmp(line, "ENDCHAR") == 0) {
			in_char = 0;
			current = -1;
		} else if (strcmp(line, "ENCODING") == 0) {
			if (sscanf(arg, "%d", &current) == 1) {
				if (current >= 0 && current < 256) {
					if (current < first) first = current;
					if (current > last) last = current;
				}
			}
		} else if (strcmp(line, "BBX") == 0) {
			int cx, cy, cwi, che;
			if (sscanf(arg, "%d %d %d %d", &cwi, &che, &cx, &cy)
			     == 4) {
				left = cx;
				lines = che;
				top = height + y - che - cy;
				if (left < bl) bl = left;
				if (top < bt) bt = top;
				if ((left + cwi) > br) br = left + cwi;
				if ((top + che) > bb) bb = top + che;
			}
		} else if (strcmp(line, "BITMAP") == 0) {
			int i, j, k, l;
			char num[32];
			char *gptr = &buffer[charsize * current];
			char *bptr = gptr + top;
			uint16_t *bptr16 = (uint16_t *)gptr;
			bptr16 += top;
			/* see if the character is in range */
			if ((current < 0) || (current > 255)) continue;
			/* now we read & render the character */
			for (i = 0; i < lines; i++) {
				fgets(num, 32, foo);
				sscanf(num, "%x", &l);
				if ((stride) == 2 && (strlen(num) < 4))
					l = l << 8;
				l = l >> left;
				if (stride == 1) {
					*gptr = l;
					gptr++;
				} else {
					*bptr16 = htobe16(l);
					bptr16++;
				}			
			}
		}
	}
	printf("range %d to %d\n", first, last);
	printf("actual box: %d %d %d %d\n", bl, bt, br, bb);
	/* now stuff it into a something wsfont understands */
	f.fontwidth = width /*(width + 3) & ~3*/;
	f.fontheight = height;
	f.firstchar = first;
	f.numchars = last - first;
	f.stride = stride;
	f.encoding = WSDISPLAY_FONTENC_ISO;
	f.name = name;
	f.bitorder = WSDISPLAY_FONTORDER_L2R;
	f.byteorder = WSDISPLAY_FONTORDER_L2R;
	f.data = &buffer[first * charsize];

	fdev = open("/dev/wsfont", O_RDWR, 0);
	if (fdev < 0) errx(1, "unable to open /dev/wsfont");	
	ioctl(fdev, WSDISPLAYIO_LDFONT, &f);
	close(fdev);
}

void
main(int argc, char *argv[])
{
	FILE *foo;
	if (argc > 1) {
		foo = fopen(argv[1], "r");
		if (foo == NULL) {
			printf("fopen error %d\n", errno);
			return;
		}
		interpret(foo);
	} else {
		printf("usage: bdfload <arg>\n");
	}
}