source: MondoRescue/branches/stable/mindi-busybox/util-linux/fbset.c@ 1770

/* vi: set sw=4 ts=4: */
/*
 * Mini fbset implementation for busybox
 *
 * Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 *
 * This is a from-scratch implementation of fbset; but the de facto fbset
 * implementation was a good reference. fbset (original) is released under
 * the GPL, and is (c) 1995-1999 by:
 *     Geert Uytterhoeven (Geert.Uytterhoeven@cs.kuleuven.ac.be)
 */

#include "libbb.h"

#define DEFAULTFBDEV  FB_0
#define DEFAULTFBMODE "/etc/fb.modes"

enum {
    OPT_CHANGE   = (1 << 0),
    OPT_INFO     = (1 << 1),
    OPT_READMODE = (1 << 2),
    OPT_ALL      = (1 << 9),

    CMD_FB = 1,
    CMD_DB = 2,
    CMD_GEOMETRY = 3,
    CMD_TIMING = 4,
    CMD_ACCEL = 5,
    CMD_HSYNC = 6,
    CMD_VSYNC = 7,
    CMD_LACED = 8,
    CMD_DOUBLE = 9,
/*  CMD_XCOMPAT =     10, */
    CMD_ALL = 11,
    CMD_INFO = 12,
    CMD_CHANGE = 13,

#if ENABLE_FEATURE_FBSET_FANCY
    CMD_XRES = 100,
    CMD_YRES = 101,
    CMD_VXRES = 102,
    CMD_VYRES = 103,
    CMD_DEPTH = 104,
    CMD_MATCH = 105,
    CMD_PIXCLOCK = 106,
    CMD_LEFT = 107,
    CMD_RIGHT = 108,
    CMD_UPPER = 109,
    CMD_LOWER = 110,
    CMD_HSLEN = 111,
    CMD_VSLEN = 112,
    CMD_CSYNC = 113,
    CMD_GSYNC = 114,
    CMD_EXTSYNC = 115,
    CMD_BCAST = 116,
    CMD_RGBA = 117,
    CMD_STEP = 118,
    CMD_MOVE = 119,
#endif
};

static unsigned g_options;

/* Stuff stolen from the kernel's fb.h */
#define FB_ACTIVATE_ALL 64
enum {
    FBIOGET_VSCREENINFO = 0x4600,
    FBIOPUT_VSCREENINFO = 0x4601
};
struct fb_bitfield {
    uint32_t offset;                /* beginning of bitfield */
    uint32_t length;        /* length of bitfield */
    uint32_t msb_right;             /* !=0: Most significant bit is right */
};
struct fb_var_screeninfo {
    uint32_t xres;                  /* visible resolution */
    uint32_t yres;
    uint32_t xres_virtual;          /* virtual resolution */
    uint32_t yres_virtual;
    uint32_t xoffset;               /* offset from virtual to visible */
    uint32_t yoffset;               /* resolution */

    uint32_t bits_per_pixel;
    uint32_t grayscale;             /* !=0 Graylevels instead of colors */

    struct fb_bitfield red;         /* bitfield in fb mem if true color, */
    struct fb_bitfield green;       /* else only length is significant */
    struct fb_bitfield blue;
    struct fb_bitfield transp;      /* transparency */

    uint32_t nonstd;                /* !=0 Non standard pixel format */

    uint32_t activate;              /* see FB_ACTIVATE_x */

    uint32_t height;                /* height of picture in mm */
    uint32_t width;                 /* width of picture in mm */

    uint32_t accel_flags;       /* acceleration flags (hints)   */

    /* Timing: All values in pixclocks, except pixclock (of course) */
    uint32_t pixclock;              /* pixel clock in ps (pico seconds) */
    uint32_t left_margin;           /* time from sync to picture */
    uint32_t right_margin;          /* time from picture to sync */
    uint32_t upper_margin;          /* time from sync to picture */
    uint32_t lower_margin;
    uint32_t hsync_len;             /* length of horizontal sync */
    uint32_t vsync_len;             /* length of vertical sync */
    uint32_t sync;                  /* see FB_SYNC_x */
    uint32_t vmode;                 /* see FB_VMODE_x */
    uint32_t reserved[6];           /* Reserved for future compatibility */
};


static const struct cmdoptions_t {
    const char name[10];
    const unsigned char param_count;
    const unsigned char code;
} g_cmdoptions[] = {
    { "-fb", 1, CMD_FB },
    { "-db", 1, CMD_DB },
    { "-a", 0, CMD_ALL },
    { "-i", 0, CMD_INFO },
    { "-g", 5, CMD_GEOMETRY },
    { "-t", 7, CMD_TIMING },
    { "-accel", 1, CMD_ACCEL },
    { "-hsync", 1, CMD_HSYNC },
    { "-vsync", 1, CMD_VSYNC },
    { "-laced", 1, CMD_LACED },
    { "-double", 1, CMD_DOUBLE },
    { "-n", 0, CMD_CHANGE },
#if ENABLE_FEATURE_FBSET_FANCY
    { "-all", 0, CMD_ALL },
    { "-xres", 1, CMD_XRES },
    { "-yres", 1, CMD_YRES },
    { "-vxres", 1, CMD_VXRES },
    { "-vyres", 1, CMD_VYRES },
    { "-depth", 1, CMD_DEPTH },
    { "-match", 0, CMD_MATCH },
    { "-geometry", 5, CMD_GEOMETRY },
    { "-pixclock", 1, CMD_PIXCLOCK },
    { "-left", 1, CMD_LEFT },
    { "-right", 1, CMD_RIGHT },
    { "-upper", 1, CMD_UPPER },
    { "-lower", 1, CMD_LOWER },
    { "-hslen", 1, CMD_HSLEN },
    { "-vslen", 1, CMD_VSLEN },
    { "-timings", 7, CMD_TIMING },
    { "-csync", 1, CMD_CSYNC },
    { "-gsync", 1, CMD_GSYNC },
    { "-extsync", 1, CMD_EXTSYNC },
    { "-bcast", 1, CMD_BCAST },
    { "-rgba", 1, CMD_RGBA },
    { "-step", 1, CMD_STEP },
    { "-move", 1, CMD_MOVE },
#endif
    { "", 0, 0 }
};

#if ENABLE_FEATURE_FBSET_READMODE
/* taken from linux/fb.h */
enum {
    FB_VMODE_INTERLACED = 1,    /* interlaced   */
    FB_VMODE_DOUBLE = 2,    /* double scan */
    FB_SYNC_HOR_HIGH_ACT = 1,   /* horizontal sync high active  */
    FB_SYNC_VERT_HIGH_ACT = 2,  /* vertical sync high active    */
    FB_SYNC_EXT = 4,    /* external sync        */
    FB_SYNC_COMP_HIGH_ACT = 8   /* composite sync high active   */
};
#endif

static int readmode(struct fb_var_screeninfo *base, const char *fn,
                    const char *mode)
{
#if ENABLE_FEATURE_FBSET_READMODE
    FILE *f;
    char buf[256];
    char *p = buf;

    f = xfopen(fn, "r");
    while (!feof(f)) {
        fgets(buf, sizeof(buf), f);
        if (!(p = strstr(buf, "mode ")) && !(p = strstr(buf, "mode\t")))
            continue;
        p += 5;
        if (!(p = strstr(buf, mode)))
            continue;
        p += strlen(mode);
        if (!isspace(*p) && (*p != 0) && (*p != '"')
                && (*p != '\r') && (*p != '\n'))
            continue;   /* almost, but not quite */

        while (!feof(f)) {
            fgets(buf, sizeof(buf), f);
            if ((p = strstr(buf, "geometry "))) {
                p += 9;
                /* FIXME: catastrophic on arches with 64bit ints */
                sscanf(p, "%d %d %d %d %d",
                    &(base->xres), &(base->yres),
                    &(base->xres_virtual), &(base->yres_virtual),
                    &(base->bits_per_pixel));
            } else if ((p = strstr(buf, "timings "))) {
                p += 8;
                sscanf(p, "%d %d %d %d %d %d %d",
                    &(base->pixclock),
                    &(base->left_margin), &(base->right_margin),
                    &(base->upper_margin), &(base->lower_margin),
                    &(base->hsync_len), &(base->vsync_len));
            } else if ((p = strstr(buf, "laced "))) {
                //p += 6;
                if (strstr(buf, "false")) {
                    base->vmode &= ~FB_VMODE_INTERLACED;
                } else {
                    base->vmode |= FB_VMODE_INTERLACED;
                }
            } else if ((p = strstr(buf, "double "))) {
                //p += 7;
                if (strstr(buf, "false")) {
                    base->vmode &= ~FB_VMODE_DOUBLE;
                } else {
                    base->vmode |= FB_VMODE_DOUBLE;
                }
            } else if ((p = strstr(buf, "vsync "))) {
                //p += 6;
                if (strstr(buf, "low")) {
                    base->sync &= ~FB_SYNC_VERT_HIGH_ACT;
                } else {
                    base->sync |= FB_SYNC_VERT_HIGH_ACT;
                }
            } else if ((p = strstr(buf, "hsync "))) {
                //p += 6;
                if (strstr(buf, "low")) {
                    base->sync &= ~FB_SYNC_HOR_HIGH_ACT;
                } else {
                    base->sync |= FB_SYNC_HOR_HIGH_ACT;
                }
            } else if ((p = strstr(buf, "csync "))) {
                //p += 6;
                if (strstr(buf, "low")) {
                    base->sync &= ~FB_SYNC_COMP_HIGH_ACT;
                } else {
                    base->sync |= FB_SYNC_COMP_HIGH_ACT;
                }
            } else if ((p = strstr(buf, "extsync "))) {
                //p += 8;
                if (strstr(buf, "false")) {
                    base->sync &= ~FB_SYNC_EXT;
                } else {
                    base->sync |= FB_SYNC_EXT;
                }
            }

            if (strstr(buf, "endmode"))
                return 1;
        }
    }
#else
    bb_error_msg("mode reading not compiled in");
#endif
    return 0;
}

static inline void setmode(struct fb_var_screeninfo *base,
                    struct fb_var_screeninfo *set)
{
    if ((int) set->xres > 0)
        base->xres = set->xres;
    if ((int) set->yres > 0)
        base->yres = set->yres;
    if ((int) set->xres_virtual > 0)
        base->xres_virtual = set->xres_virtual;
    if ((int) set->yres_virtual > 0)
        base->yres_virtual = set->yres_virtual;
    if ((int) set->bits_per_pixel > 0)
        base->bits_per_pixel = set->bits_per_pixel;
}

static inline void showmode(struct fb_var_screeninfo *v)
{
    double drate = 0, hrate = 0, vrate = 0;

    if (v->pixclock) {
        drate = 1e12 / v->pixclock;
        hrate = drate / (v->left_margin + v->xres + v->right_margin + v->hsync_len);
        vrate = hrate / (v->upper_margin + v->yres + v->lower_margin + v->vsync_len);
    }
    printf("\nmode \"%ux%u-%u\"\n"
#if ENABLE_FEATURE_FBSET_FANCY
    "\t# D: %.3f MHz, H: %.3f kHz, V: %.3f Hz\n"
#endif
    "\tgeometry %u %u %u %u %u\n"
    "\ttimings %u %u %u %u %u %u %u\n"
    "\taccel %s\n"
    "\trgba %u/%u,%u/%u,%u/%u,%u/%u\n"
    "endmode\n\n",
        v->xres, v->yres, (int) (vrate + 0.5),
#if ENABLE_FEATURE_FBSET_FANCY
        drate / 1e6, hrate / 1e3, vrate,
#endif
        v->xres, v->yres, v->xres_virtual, v->yres_virtual, v->bits_per_pixel,
        v->pixclock, v->left_margin, v->right_margin, v->upper_margin, v->lower_margin,
            v->hsync_len, v->vsync_len,
        (v->accel_flags > 0 ? "true" : "false"),
        v->red.length, v->red.offset, v->green.length, v->green.offset,
            v->blue.length, v->blue.offset, v->transp.length, v->transp.offset);
}

#ifdef STANDALONE
int main(int argc, char **argv)
#else
int fbset_main(int argc, char **argv);
int fbset_main(int argc, char **argv)
#endif
{
    struct fb_var_screeninfo var, varset;
    int fh, i;
    const char *fbdev = DEFAULTFBDEV;
    const char *modefile = DEFAULTFBMODE;
    char *thisarg, *mode = NULL;

    memset(&varset, 0xFF, sizeof(varset));

    /* parse cmd args.... why do they have to make things so difficult? */
    argv++;
    argc--;
    for (; argc > 0 && (thisarg = *argv); argc--, argv++) {
        for (i = 0; g_cmdoptions[i].name[0]; i++) {
            if (strcmp(thisarg, g_cmdoptions[i].name))
                continue;
            if (argc-1 < g_cmdoptions[i].param_count)
                bb_show_usage();

            switch (g_cmdoptions[i].code) {
            case CMD_FB:
                fbdev = argv[1];
                break;
            case CMD_DB:
                modefile = argv[1];
                break;
            case CMD_GEOMETRY:
                varset.xres = xatou32(argv[1]);
                varset.yres = xatou32(argv[2]);
                varset.xres_virtual = xatou32(argv[3]);
                varset.yres_virtual = xatou32(argv[4]);
                varset.bits_per_pixel = xatou32(argv[5]);
                break;
            case CMD_TIMING:
                varset.pixclock = xatou32(argv[1]);
                varset.left_margin = xatou32(argv[2]);
                varset.right_margin = xatou32(argv[3]);
                varset.upper_margin = xatou32(argv[4]);
                varset.lower_margin = xatou32(argv[5]);
                varset.hsync_len = xatou32(argv[6]);
                varset.vsync_len = xatou32(argv[7]);
                break;
            case CMD_ALL:
                g_options |= OPT_ALL;
                break;
            case CMD_CHANGE:
                g_options |= OPT_CHANGE;
                break;
#if ENABLE_FEATURE_FBSET_FANCY
            case CMD_XRES:
                varset.xres = xatou32(argv[1]);
                break;
            case CMD_YRES:
                varset.yres = xatou32(argv[1]);
                break;
            case CMD_DEPTH:
                varset.bits_per_pixel = xatou32(argv[1]);
                break;
#endif
            }
            argc -= g_cmdoptions[i].param_count;
            argv += g_cmdoptions[i].param_count;
            break;
        }
        if (!g_cmdoptions[i].name[0]) {
            if (argc != 1)
                bb_show_usage();
            mode = *argv;
            g_options |= OPT_READMODE;
        }
    }

    fh = xopen(fbdev, O_RDONLY);
    xioctl(fh, FBIOGET_VSCREENINFO, &var);
    if (g_options & OPT_READMODE) {
        if (!readmode(&var, modefile, mode)) {
            bb_error_msg_and_die("unknown video mode '%s'", mode);
        }
    }

    setmode(&var, &varset);
    if (g_options & OPT_CHANGE) {
        if (g_options & OPT_ALL)
            var.activate = FB_ACTIVATE_ALL;
        xioctl(fh, FBIOPUT_VSCREENINFO, &var);
    }
    showmode(&var);
    /* Don't close the file, as exiting will take care of that */
    /* close(fh); */

    return EXIT_SUCCESS;
}