mdw@git.distorted.org.uk Git - xtoys/blob - xwait.c

   1 /* -*-c-*-
   2  *
   3  * $Id: xwait.c,v 1.1 1998/11/16 23:00:49 mdw Exp $
   4  *
   5  * Wait until prodded by another X client
   6  *
   7  * (c) 1998 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of the Edgeware X tools collection.
  13  *
  14  * X tools is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * X tools is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with X tools; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Revision history --------------------------------------------------*
  30  *
  31  * $Log: xwait.c,v $
  32  * Revision 1.1  1998/11/16 23:00:49  mdw
  33  * Initial versions.
  34  *
  35  */
  36
  37 /*----- Header files ------------------------------------------------------*/
  38
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 #include <unistd.h>
  44
  45 #include <X11/Xlib.h>
  46 #include <X11/Xutil.h>
  47
  48 #include "xwait.h"
  49
  50 /*----- Main code ---------------------------------------------------------*/
  51
  52 int main(int argc, char *argv[])
  53 {
  54   char *display = 0;
  55   Display *dpy;
  56   Atom xwait_die;
  57   XEvent ev;
  58   char *atom = XWAIT_DIE;
  59   char *msg = XWAIT_DIE_MSG;
  60   unsigned f = 0;
  61
  62   enum {
  63     f_force = 1
  64   };
  65
  66   /* --- Parse options --- */
  67
  68   for (;;) {
  69     int i = getopt(argc, argv, "d:a:m:f");
  70     if (i < 0)
  71       break;
  72     switch (i) {
  73       case 'd':
  74         display = optarg;
  75         break;
  76       case 'a':
  77         atom = optarg;
  78         break;
  79       case 'm':
  80         msg = optarg;
  81         break;
  82       case 'f':
  83         f |= f_force;
  84         break;
  85       default:
  86         fprintf(stderr,
  87                 "Usage: xwait [-f] [-d DISPLAY] [-a ATOM] [-m MSG]\n");
  88         exit(EXIT_FAILURE);
  89         break;
  90     }
  91   }
  92
  93   /* --- Connect to the X display --- */
  94
  95   dpy = XOpenDisplay(display);
  96   if (!dpy) {
  97     fprintf(stderr, "xwait: couldn't open display\n");
  98     exit(EXIT_FAILURE);
  99   }
 100
 101   /* --- Fetch the property name atom --- */
 102
 103   xwait_die = XInternAtom(dpy, atom, False);
 104
 105   /* --- Mark ourselves as listening to all the screens --- */
 106
 107   {
 108     int i;
 109     int nsc = ScreenCount(dpy);
 110
 111     /* --- First pass: make sure there's not a process already here --- */
 112
 113     if ((f & f_force) == 0) {
 114       for (i = 0; i < nsc; i++) {
 115         Window win = RootWindow(dpy, i);
 116         XTextProperty prop;
 117
 118         if (XGetTextProperty(dpy, win, &prop, xwait_die)) {
 119           fprintf(stderr, "xwait: already waiting for `%s'\n", atom);
 120           exit(EXIT_FAILURE);
 121         }
 122       }
 123     }
 124
 125     /* --- Second pass: set up listening to the property --- */
 126
 127     for (i = 0; i < nsc; i++) {
 128       Window win = RootWindow(dpy, i);
 129       XTextProperty prop;
 130       char *imsg = "XWAIT_READY";
 131
 132       XStringListToTextProperty(&imsg, 1, &prop);
 133       XSetTextProperty(dpy, win, &prop, xwait_die);
 134       XSelectInput(dpy, win, PropertyChangeMask);
 135     }
 136   }
 137
 138   /* --- Now wait for an event --- */
 139
 140   for (;;) {
 141     XNextEvent(dpy, &ev);
 142     switch (ev.type) {
 143       case PropertyNotify:
 144         if (ev.xproperty.atom == xwait_die) {
 145           XTextProperty prop;
 146           char **sl;
 147           int c;
 148
 149           if (XGetTextProperty(dpy, ev.xproperty.window, &prop, xwait_die)) {
 150             XTextPropertyToStringList(&prop, &sl, &c);
 151             if (strcmp(sl[0], msg) == 0)
 152               goto exit;
 153             XFreeStringList(sl);
 154           }
 155         }
 156     }
 157   }
 158
 159   /* --- Finished: remove the property from all the screens --- */
 160
 161 exit:
 162   {
 163     int i;
 164     int nsc = ScreenCount(dpy);
 165
 166     for (i = 0; i < nsc; i++)
 167       XDeleteProperty(dpy, RootWindow(dpy, i), xwait_die);
 168   }
 169
 170   /* --- Go away --- */
 171
 172   XCloseDisplay(dpy);
 173   return (0);
 174 }
 175
 176 /*----- That's all, folks -------------------------------------------------*/