sys/src/libdraw/readcolmap.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <draw.h>
   4 #include <bio.h>
   5
   6 static ulong
   7 getval(char **p)
   8 {
   9         ulong v;
  10         char *q;
  11
  12         v = strtoul(*p, &q, 0);
  13         v |= v<<8;
  14         v |= v<<16;
  15         *p = q;
  16         return v;
  17 }
  18
  19 void
  20 readcolmap(Display *d, RGB *colmap)
  21 {
  22         int i;
  23         char *p, *q;
  24         Biobuf *b;
  25         char buf[128];
  26
  27         USED(screen);
  28
  29         sprint(buf, "/dev/draw/%d/colormap", d->dirno);
  30         b = Bopen(buf, OREAD);
  31         if(b == 0)
  32                 drawerror(d, "rdcolmap: can't open colormap device");
  33
  34         for(;;) {
  35                 p = Brdline(b, '\n');
  36                 if(p == 0)
  37                         break;
  38                 i = strtoul(p, &q, 0);
  39                 if(i < 0 || i > 255) {
  40                         fprint(2, "rdcolmap: bad index\n");
  41                         exits("bad");
  42                 }
  43                 p = q;
  44                 colmap[255-i].red = getval(&p);
  45                 colmap[255-i].green = getval(&p);
  46                 colmap[255-i].blue = getval(&p);
  47         }
  48         Bterm(b);
  49 }