source: MondoRescue/branches/2.2.8.selinux/mindi-busybox/console-tools/loadfont.c@ 2850

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

    if (argc != 1)
        bb_show_usage();

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

    return EXIT_SUCCESS;
}