vga.c

linux 下svgalib编的一个界面程序示例

static unsigned char *__svgalib_graph_mem_orginal;
static unsigned char *__svgalib_graph_mem_check;
unsigned char *__svgalib_graph_mem_linear_orginal;
unsigned char *__svgalib_graph_mem_linear_check;
static int __svgalib_linear_is_background=0;
int __svgalib_oktowrite=1;

/* __svgalib_oktowrite tells if it is safe to write registers. */

int __svgalib_currentpage;
int __svgalib_virtual_mem_fd=-1;
static int __svgalib_processnumber=-1;
static unsigned char *graph_buf2 = NULL;	/* saves linear graphics data during flip */

#endif

void *__svgalib_physaddr;
int __svgalib_linear_memory_size;


#ifdef __alpha__

/* same as graph mem, but mapped through sparse memory: */
unsigned char *__svgalib_sparse_mem;

#endif

static unsigned char *graph_buf = NULL;		/* saves graphics data during flip */

static unsigned char *font_buf1;	/* saved font data - plane 2 */
static unsigned char *font_buf2;	/* saved font data - plane 3 */
static unsigned char *text_buf1;	/* saved text data - plane 0 */
static unsigned char *text_buf2;	/* saved text data - plane 1 */

static struct termios text_termio;	/* text mode termio parameters     */
static struct termios graph_termio;	/* graphics mode termio parameters */

int __svgalib_flipchar = '\x1b';		/* flip character - initially  ESCAPE */

/* Chipset specific functions */

DriverSpecs *__svgalib_driverspecs = &__svgalib_vga_driverspecs;

#ifndef BACKGROUND
static void (*__svgalib_setpage) (int);	/* gives little faster vga_setpage() */
static void (*__svgalib_setrdpage) (int);
static void (*__svgalib_setwrpage) (int);
#endif
#ifdef BACKGROUND
void (*__svgalib_setpage) (int);	
void (*__svgalib_setrdpage) (int);
void (*__svgalib_setwrpage) (int);
#endif

static void readconfigfile(void);

DriverSpecs *__svgalib_driverspecslist[] =
{
    NULL,			/* chipset undefined */
    &__svgalib_vga_driverspecs,
#ifdef INCLUDE_ET4000_DRIVER
    &__svgalib_et4000_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_CIRRUS_DRIVER
    &__svgalib_cirrus_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_TVGA_DRIVER
    &__svgalib_tvga8900_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_OAK_DRIVER
    &__svgalib_oak_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_EGA_DRIVER
    &__svgalib_ega_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_S3_DRIVER
    &__svgalib_s3_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_ET3000_DRIVER
    &__svgalib_et3000_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_MACH32_DRIVER
    &__svgalib_mach32_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_GVGA6400_DRIVER
    &__svgalib_gvga6400_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_ARK_DRIVER
    &__svgalib_ark_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_ATI_DRIVER
    &__svgalib_ati_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_ALI_DRIVER
    &__svgalib_ali_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_MACH64_DRIVER
    &__svgalib_mach64_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_CHIPS_DRIVER
    &__svgalib_chips_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_APM_DRIVER
    &__svgalib_apm_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_NV3_DRIVER
    &__svgalib_nv3_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_ET6000_DRIVER
    &__svgalib_et6000_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_VESA_DRIVER
    &__svgalib_vesa_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_MX_DRIVER
    &__svgalib_mx_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_PARADISE_DRIVER
    &__svgalib_paradise_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_RAGE_DRIVER
    &__svgalib_rage_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_BANSHEE_DRIVER
    &__svgalib_banshee_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_SIS_DRIVER
    &__svgalib_sis_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_I740_DRIVER
    &__svgalib_i740_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_NEO_DRIVER
    &__svgalib_neo_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_LAGUNA_DRIVER
    &__svgalib_laguna_driverspecs,
#else
    NULL,
#endif
#ifdef INCLUDE_FBDEV_DRIVER
     &__svgalib_fbdev_driverspecs,
#else
     NULL,
#endif
#ifdef INCLUDE_G400_DRIVER
     &__svgalib_g400_driverspecs,
#else
     NULL,
#endif
#ifdef INCLUDE_R128_DRIVER
     &__svgalib_r128_driverspecs,
#else
     NULL,
#endif
#ifdef INCLUDE_SAVAGE_DRIVER
     &__svgalib_savage_driverspecs,
#else
     NULL,
#endif
};

static char *driver_names[] =
{
"", 
"VGA", 
"ET4000", 
"Cirrus", 
"TVGA", 
"Oak", 
"EGA", 
"S3",
"ET3000", 
"Mach32", 
"GVGA6400",
"ARK",
"ATI",
"ALI",
"Mach64", 
"C&T",
"APM",
"NV3",
"ET6000",
"VESA",
"MX",
"PARADISE",
"RAGE",
"BANSHEE", 
"SIS",
"I740",
"NEOMAGIC",
"LAGUNA",
"FBDev",
"G400",
"R128",
"Savage",
 NULL};

/* Chipset drivers */

/* vgadrv       Standard VGA (also used by drivers below) */
/* et4000       Tseng ET4000 (from original vgalib) */
/* cirrus       Cirrus Logic GD542x */
/* tvga8900     Trident TVGA 8900/9000 (derived from tvgalib) */
/* oak          Oak Technologies 037/067/077 */
/* egadrv       IBM EGA (subset of VGA) */
/* s3           S3 911 */
/* mach32       ATI MACH32 */
/* ark          ARK Logic */
/* gvga6400     Genoa 6400 (old SVGA) */
/* ati          ATI */
/* ali          ALI2301 */
/* mach64	ATI MACH64 */
/* chips	chips & technologies*/
/* et6000       Tseng ET6000 */         /* DS */

/*#define DEBUG */

/* Debug config file parsing.. */
/*#define DEBUG_CONF */

#ifdef DEBUG
static void _DEBUG(int dnr)
{
    static int first = 1;
    FILE *dfile;

    dfile = fopen("svgalib.debug", (first ? "w" : "a"));
    first = 0;
    if (dfile == NULL)
	exit(1);
    fprintf(dfile, "debug #%d\n", dnr);
    fclose(dfile);
    sync();
}
#else
#define _DEBUG(d)
#endif

static void set_graphtermio(void)
{
    /* Leave keyboard alone when rawkeyboard is enabled! */
    if (__svgalib_kbd_fd < 0) {
	/* set graphics mode termio parameters */
	ioctl(0, TCSETSW, &graph_termio);
    }
}


static void set_texttermio(void)
{
    /* Leave keyboard alone when rawkeyboard is enabled! */
    if (__svgalib_kbd_fd < 0) {
	/* restore text mode termio parameters */
	ioctl(0, TCSETSW, &text_termio);
    }
}


static void disable_interrupt(void)
{
    struct termios cur_termio;

    /* Well, one could argue that sigint is not enabled at all when in __svgalib_nosigint
       but sometimes they *still* are enabled b4 graph_termio is set.. */
    ioctl(0, TCGETS, &cur_termio);
    cur_termio.c_lflag &= ~ISIG;
    ioctl(0, TCSETSW, &cur_termio);
}


static void enable_interrupt(void)
{
    struct termios cur_termio;

    if (__svgalib_nosigint) /* do not reenable, they are often reenabled by text_termio */
	return; 
    ioctl(0, TCGETS, &cur_termio);
    cur_termio.c_lflag |= ISIG;
    ioctl(0, TCSETSW, &cur_termio);
}

/* The following is rather messy and inelegant. The only solution I can */
/* see is getting a extra free VT for graphics like XFree86 does. */

void __svgalib_waitvtactive(void)
{
    if (__svgalib_tty_fd < 0)
	return; /* Not yet initialized */

    while (ioctl(__svgalib_tty_fd, VT_WAITACTIVE, svgalib_vc) < 0) {
	if ((errno != EAGAIN) && (errno != EINTR)) {
	    perror("ioctl(VT_WAITACTIVE)");
	    exit(1);
	}
	usleep(150000);
    }
}


/* open /dev/mem */
static void open_mem(void)
{
#ifdef BACKGROUND
#if BACKGROUND == 1
 char tmp[40];
#endif
#endif

    if (CHIPSET == FBDEV)
	return;

    /*  Ensure that the open will get a file descriptor greater
     *  than 2, else problems can occur with stdio functions
     *  under certain strange conditions:  */
    if (fcntl(0,F_GETFD) < 0) open("/dev/null", O_RDONLY);
    if (fcntl(1,F_GETFD) < 0) open("/dev/null", O_WRONLY);
    if (fcntl(2,F_GETFD) < 0) open("/dev/null", O_WRONLY);

    if (__svgalib_mem_fd < 0)
	if ((__svgalib_mem_fd = open("/dev/mem", O_RDWR)) < 0) {
	    printf("svgalib: Cannot open /dev/mem.\n");
	    exit(1);
	}
#ifdef BACKGROUND
#if BACKGROUND == 1

    /* Needs proc-fs. */
    /* printf("procc\n"); */
    /* char tmp[40];*/
    if (__svgalib_virtual_mem_fd<0)
        {
	 __svgalib_processnumber=getpid(); 
	 sprintf(tmp,"/proc/%d/mem",__svgalib_processnumber);
	 if ((__svgalib_virtual_mem_fd = open(tmp,O_RDWR)) < 0) 
	     {
	      printf("svgalib: Cannot open /proc/%d/mem.\n",
	          __svgalib_processnumber);
	      exit(-1);
	     }
	}
#endif
#endif
}

static int check_owner(int vc)
{
    struct stat sbuf;
    char fname[30];

#ifdef ROOT_VC_SHORTCUT
    if (!getuid())
        return 1;               /* root can do it always */
#endif
    sprintf(fname, "/dev/tty%d", vc);
    if ((stat(fname, &sbuf) >= 0) && (getuid() == sbuf.st_uid)) {
        return 1;
    }
    printf("You must be the owner of the current console to use svgalib.\n");
    return 0;
}

void __svgalib_open_devconsole(void)
{
    struct vt_mode vtm;
    struct vt_stat vts;
    struct stat sbuf;
    char fname[30];

    if(__svgalib_novccontrol)return;

    if (__svgalib_tty_fd >= 0)
        return;

    /*  The code below assumes file descriptors 0, 1, and 2
     *  are already open; make sure that's true.  */
    if (fcntl(0,F_GETFD) < 0) open("/dev/null", O_RDONLY);
    if (fcntl(1,F_GETFD) < 0) open("/dev/null", O_WRONLY);
    if (fcntl(2,F_GETFD) < 0) open("/dev/null", O_WRONLY);

    /*
     * Now, it would be great if we could use /dev/tty and see what it is connected to.
     * Alas, we cannot find out reliably what VC /dev/tty is bound to. Thus we parse
     * stdin through stderr for a reliable VC
     */
    for (__svgalib_tty_fd = 0; __svgalib_tty_fd < 3; __svgalib_tty_fd++) {
        if (fstat(__svgalib_tty_fd, &sbuf) < 0)
            continue;
        if (ioctl(__svgalib_tty_fd, VT_GETMODE, &vtm) < 0)
            continue;
        if ((sbuf.st_rdev & 0xff00) != 0x400)
            continue;
        if (!(sbuf.st_rdev & 0xff))
            continue;
        svgalib_vc = sbuf.st_rdev & 0xff;
        return;                 /* perfect */
    }

    if ((__svgalib_tty_fd = open("/dev/console", O_RDWR)) < 0) {
        printf("svgalib: can't open /dev/console \n");
        exit(1);
    }
    if (ioctl(__svgalib_tty_fd, VT_OPENQRY, &svgalib_vc) < 0)
        goto error;
    if (svgalib_vc <= 0)
        goto error;
    sprintf(fname, "/dev/tty%d", svgalib_vc);
    close(__svgalib_tty_fd);
    /* change our control terminal: */
    setpgid(0,getppid());
    setsid();
    /* We must use RDWR to allow for output... */
    if (((__svgalib_tty_fd = open(fname, O_RDWR)) >= 0) &&
        (ioctl(__svgalib_tty_fd, VT_GETSTATE, &vts) >= 0)) {
        if (!check_owner(vts.v_active))
            goto error;
        /* success, redirect all stdios */
        if (DREP)
            printf("[svgalib: allocated virtual console #%d]\n", svgalib_vc);
        fflush(stdin);
        fflush(stdout);
        fflush(stderr);
        close(0);
        close(1);
        close(2);
        dup(__svgalib_tty_fd);
        dup(__svgalib_tty_fd);
        dup(__svgalib_tty_fd);