linux下的framebuffer显示图片

void  showbmp2()
 {
     int x,y;
     unsigned char *p;
     int index=0;
     struct fb_var_screeninfo vinfo; 
     struct fb_fix_screeninfo finfo; 

     struct fb_bitfield red; 
     struct fb_bitfield green; 
     struct fb_bitfield blue; 

     //open the showdeviece
     fbfd = open("/dev/fb0", O_RDWR); 
     if (!fbfd) 
     { 
  printf("Error: cannot open framebuffer device.\n"); 
  exit(1); 
     } 
  
     if (ioctl(fbfd, FBIOGET_FSCREENINFO, &finfo)) 
     { 
  printf("Error£ºreading fixed information.\n"); 
  exit(2); 
     } 
  
     if (ioctl(fbfd, FBIOGET_VSCREENINFO, &vinfo)) 
     { 
  printf("Error: reading variable information.\n"); 
  exit(3); 
     } 
  
     printf("R:%d,G:%d,B:%d \n", vinfo.red, vinfo.green, vinfo.blue ); 
  
     printf("%dx%d, %dbpp\n", vinfo.xres, vinfo.yres, vinfo.bits_per_pixel ); 
     xres = vinfo.xres; 
     yres = vinfo.yres; 
     bits_per_pixel = vinfo.bits_per_pixel; 
  
     //ŒÆËãÆÁÄ»µÄ×ÜŽóС£š×֜ڣ©  
     screensize = vinfo.xres * vinfo.yres * vinfo.bits_per_pixel / 8; 
     printf("screensize=%d byte\n",screensize); 
  
     //¶ÔÏóÓ³Éä  
     fbp = (char *)mmap(0, screensize, PROT_READ | PROT_WRITE, MAP_SHARED, fbfd, 0); 
     if ((int)fbp == -1) 
     { 
  printf("Error: failed to map framebuffer device to memory.\n"); 
  exit(4); 
     } 
  
     printf("sizeof file header=%d\n", sizeof(BITMAPFILEHEADER)); 
  
     printf("into show_bmp function\n"); 
     FILE *fp[3];

  fp[0] = fopen("./333.bmp","rb+");
  fp[1] = fopen("./444.bmp","rb+");
  fp[2] = fopen("./555.bmp","rb+");

     fread(data,54,1,fp[0]);
     fread(data,WIDTH*HEIGHT*3,1,fp[0]);
     for(y=0;y<HEIGHT;y++)
     {
  for(x=0;x<WIDTH;x++)
  {
      //if(x<640)
      {
       buf[1][(((HEIGHT-1)-y)*WIDTH+x)*4 + 0] = data[((y*WIDTH) + x)*3 + 0];
          buf[1][(((HEIGHT-1)-y)*WIDTH+x)*4 + 1] = data[((y*WIDTH) + x)*3 + 1];
          buf[1][(((HEIGHT-1)-y)*WIDTH+x)*4 + 2] = data[((y*WIDTH) + x)*3 + 2];
          //buf[1][(479-y)*WIDTH+x)*4 + 3] = data[((y*640) + x)*3 + 0];
      }
  }
     }
 //
     fread(data,54,1,fp[1]);
     fread(data,WIDTH*HEIGHT*3,1,fp[1]);
     for(y=0;y<HEIGHT;y++)
     {
  for(x=0;x<WIDTH;x++)
  {
      //if(x<640)
      {
       buf[2][(((HEIGHT-1)-y)*WIDTH+x)*4 + 0] = data[((y*WIDTH) + x)*3 + 0];
          buf[2][(((HEIGHT-1)-y)*WIDTH+x)*4 + 1] = data[((y*WIDTH) + x)*3 + 1];
          buf[2][(((HEIGHT-1)-y)*WIDTH+x)*4 + 2] = data[((y*WIDTH) + x)*3 + 2];
          //buf[1][(479-y)*WIDTH+x)*4 + 3] = data[((y*640) + x)*3 + 0];
      }
  }
     }
 //
     fread(data,54,1,fp[2]);
     fread(data,WIDTH*HEIGHT*3,1,fp[2]);
     for(y=0;y<HEIGHT;y++)  
     {
  for(x=0;x<WIDTH;x++)
  {
     // if(x<640)
       {
       buf[3][(((HEIGHT-1)-y)*WIDTH+x)*4 + 0] = data[((y*WIDTH) + x)*3 + 0];
          buf[3][(((HEIGHT-1)-y)*WIDTH+x)*4 + 1] = data[((y*WIDTH) + x)*3 + 1];
          buf[3][(((HEIGHT-1)-y)*WIDTH+x)*4 + 2] = data[((y*WIDTH) + x)*3 + 2];
          //buf[1][(479-y)*WIDTH+x)*4 + 3] = data[((y*640) + x)*3 + 0];
      }
  }
     }
     fclose(fp[0]); fclose(fp[1]); fclose(fp[2]);
     //
     while(1)
     {

      memcpy(fbp,buf[index++%picindex + 1],WIDTH*HEIGHT*4);
      sleep(2);

     }   
     printf("/nover!/n");

     return ;
 }