admin/alloc-colors.c

   1 /* Allocate X colors.  Used for testing with dense colormaps.
   2
   3 Copyright (C) 2001-2024 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software: you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation, either version 3 of the License, or (at
  10 your option) any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
  19
  20
  21 #include <X11/Xlib.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stdarg.h>
  25 #include <unistd.h>
  26 #include <string.h>
  27
  28 void
  29 fatal (const char *fmt, ...)
  30 {
  31   va_list ap;
  32
  33   va_start (ap, fmt);
  34   vfprintf (stderr, fmt, ap);
  35   fputc ('\n', stderr);
  36   va_end (ap);
  37   exit (1);
  38 }
  39
  40 void
  41 usage (const char *progname)
  42 {
  43   fprintf (stderr, "Usage %s options\n", progname);
  44   fprintf (stderr, "-n NCOLORS  allocate NCOLORS colors\n");
  45   exit (1);
  46 }
  47
  48 int
  49 main (int argc, char **argv)
  50 {
  51   Display *dpy;
  52   int opt, ncolors = 0, i;
  53   XColor *allocated;
  54   int nallocated;
  55   XColor color;
  56   Colormap cmap;
  57
  58   while ((opt = getopt (argc, argv, "n:")) != EOF)
  59     switch (opt)
  60       {
  61       case 'n':
  62         ncolors = atoi (optarg);
  63         break;
  64
  65       case '?':
  66         usage (argv[0]);
  67       }
  68
  69   if (ncolors == 0)
  70     usage (argv[0]);
  71
  72   dpy = XOpenDisplay ("");
  73   if (dpy == NULL)
  74     fatal ("Cannot open display");
  75   cmap = DefaultColormap (dpy, 0);
  76
  77   allocated = malloc (ncolors * sizeof *allocated);
  78   nallocated = 0;
  79   memset (&color, 0, sizeof color);
  80
  81   while (nallocated < ncolors
  82          && color.red < 65536)
  83     {
  84       allocated[nallocated] = color;
  85       if (XAllocColor (dpy, cmap, &allocated[nallocated]))
  86         {
  87           for (i = 0; i < nallocated; ++i)
  88             if (allocated[i].red == allocated[nallocated].red
  89                 && allocated[i].green == allocated[nallocated].green
  90                 && allocated[i].blue == allocated[nallocated].blue)
  91               break;
  92
  93           if (i == nallocated)
  94             {
  95               printf ("allocated %d/%d/%d\n",
  96                       allocated[nallocated].red,
  97                       allocated[nallocated].green,
  98                       allocated[nallocated].blue);
  99               ++nallocated;
 100             }
 101         }
 102
 103       ++color.red;
 104       ++color.green;
 105       ++color.blue;
 106     }
 107
 108   fprintf (stderr, "Waiting.  Press ^C to stop.\n");
 109   while (1)
 110     sleep (10);
 111
 112   XCloseDisplay (dpy);
 113   return 0;
 114 }