x-on-resize.c

   1 /*
   2  * Copyright © 2011 Keith Packard <keithp@keithp.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; version 2 of the License.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  16  */
  17
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include <getopt.h>
  21 #include <unistd.h>
  22 #include <X11/Xlib.h>
  23 #include <X11/extensions/Xrandr.h>
  24 #include "config.h"
  25
  26 struct output_info {
  27         struct output_info      *next;
  28         RROutput                output;
  29         XRROutputInfo           *info;
  30 };
  31
  32 static struct output_info       *output_info;
  33
  34 static struct output_info *
  35 find_output_info (RROutput output)
  36 {
  37         struct output_info      *oi;
  38
  39         for (oi = output_info; oi; oi = oi->next)
  40                 if (oi->output == output)
  41                         return oi;
  42         return NULL;
  43 }
  44
  45 static void
  46 clear_output_info (RROutput output)
  47 {
  48         struct output_info      *oi, **prev;
  49
  50         for (prev = &output_info; (oi = *prev); prev = &(oi->next))
  51                 if (oi->output == output) {
  52                         XRRFreeOutputInfo (oi->info);
  53                         *prev = oi->next;
  54                         free (oi);
  55                         break;
  56                 }
  57 }
  58
  59 /*
  60  * Check to see if the monitor attached to an output
  61  * is the same
  62  */
  63 static int
  64 same_monitor(XRROutputInfo *a, XRROutputInfo *b)
  65 {
  66         int     m;
  67
  68         if (a->connection != b->connection)
  69                 return 0;
  70         if (a->nmode != b->nmode)
  71                 return 0;
  72         if (a->npreferred != b->npreferred)
  73                 return 0;
  74         for (m = 0; m < a->nmode; m++)
  75                 if (a->modes[m] != b->modes[m])
  76                         return 0;
  77         return 1;
  78 }
  79
  80 static int
  81 check_output (Display *dpy, XRRScreenResources *resources, RROutput output)
  82 {
  83         XRROutputInfo           *info;
  84         struct output_info      *oi;
  85
  86         info = XRRGetOutputInfo (dpy, resources, output);
  87         if (!info) {
  88                 clear_output_info(output);
  89                 return 0;
  90         }
  91         oi = find_output_info(output);
  92         if (oi) {
  93                 int     same = same_monitor(oi->info, info);
  94                 XRRFreeOutputInfo(oi->info);
  95                 oi->info = info;
  96                 return same;
  97         }
  98         oi = calloc(1, sizeof (struct output_info));
  99         oi->output = output;
 100         oi->info = info;
 101         oi->next = output_info;
 102         output_info = oi;
 103         return 0;
 104 }
 105
 106
 107 int
 108 main (int argc, char **argv)
 109 {
 110         Display         *dpy;
 111         int             event_base, error_base;
 112         int             major, minor;
 113         XEvent          ev;
 114         XRRNotifyEvent  *nev;
 115         const char      *config = NULL;
 116         const char      *resize = NULL;
 117         const char      *display = NULL;
 118         int             c, o;
 119         int             start = 0;
 120         XRRScreenResources      *resources;
 121
 122         static struct option opts[] = {
 123                 { "config", 1, NULL, 'c' },
 124                 { "resize", 1, NULL, 'r' },
 125                 { "start", 0, NULL, 's' },
 126                 { "auto", 0, NULL, 'a' },
 127                 { "display", 1, NULL, 'd' },
 128                 { "help", 0, NULL, 'h' },
 129                 { "version", 0, NULL, 'v' },
 130                 { 0, 0, NULL, 0 }
 131         };
 132
 133         while ((c = getopt_long(argc, argv, "c:r:d:hsav", opts, NULL)) != -1) {
 134                 switch (c) {
 135                 case 'c':
 136                         config = optarg;
 137                         break;
 138                 case 'r':
 139                         resize = optarg;
 140                         break;
 141                 case 'd':
 142                         display = optarg;
 143                         break;
 144                 case 'a':
 145                         config = "xrandr --auto";
 146                         break;
 147                 case 's':
 148                         start = 1;
 149                         break;
 150                 case 'v':
 151                         printf("%s\n", PACKAGE_STRING);
 152                         exit(0);
 153                 case 'h':
 154                 default:
 155                         fprintf(stderr, "Usage: %s --display <display> --config <config> --resize <resize> --auto --start --version\n", argv[0]);
 156                         exit(1);
 157                         break;
 158                 }
 159         }
 160
 161         dpy = XOpenDisplay(display);
 162         if (!dpy) {
 163                 fprintf(stderr, "XOpenDisplay %s failed\n", XDisplayName(display));
 164                 exit(1);
 165         }
 166         if (!XRRQueryExtension (dpy, &event_base, &error_base) ||
 167             !XRRQueryVersion (dpy, &major, &minor))
 168         {
 169                 fprintf (stderr, "RandR extension missing on %s\n", XDisplayName(display));
 170                 exit (1);
 171         }
 172         XRRSelectInput(dpy, RootWindow(dpy, 0), RROutputChangeNotifyMask);
 173         XSelectInput(dpy, RootWindow(dpy, 0), StructureNotifyMask);
 174
 175         /* Get current configuration */
 176         resources = XRRGetScreenResourcesCurrent(dpy, RootWindow(dpy, 0));
 177         for (o = 0; o < resources->noutput; o++)
 178                 (void) check_output(dpy, resources, resources->outputs[o]);
 179         XRRFreeScreenResources (resources);
 180
 181         if (start) {
 182                 if (config)
 183                         system(config);
 184                 if (resize)
 185                         system(resize);
 186         }
 187         for (;;) {
 188                 int     configed = 0;
 189                 int     resized = 0;
 190
 191                 do {
 192                         XNextEvent(dpy, &ev);
 193                         switch (ev.type - event_base) {
 194                         case RRNotify:
 195                                 nev = (XRRNotifyEvent *) &ev;
 196                                 if (nev->subtype == RRNotify_OutputChange) {
 197                                         XRROutputChangeNotifyEvent *noev = (XRROutputChangeNotifyEvent *) nev;
 198                                         resources = XRRGetScreenResources(dpy, RootWindow(dpy, 0));
 199                                         if (!check_output(dpy, resources, noev->output))
 200                                                 configed = 1;
 201                                         XRRFreeScreenResources (resources);
 202                                 }
 203                                 break;
 204                         }
 205                         switch (ev.type) {
 206                         case ConfigureNotify:
 207                                 resized = 1;
 208                                 break;
 209                         }
 210                         usleep(100000);
 211                 } while (XEventsQueued(dpy, QueuedAfterFlush));
 212                 if (configed) {
 213                         if (config)
 214                                 system(config);
 215                         else
 216                                 printf ("config\n");
 217                 }
 218                 if (resized) {
 219                         if (resize)
 220                                 system(resize);
 221                         else
 222                                 printf ("resize\n");
 223                 }
 224         }
 225 }