use Xrandr to store monitor info; next we must use this info to place windows

client.c

@@ -6,6 +6,7 @@
 #include <X11/X.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #include "dat.h"
 #include "fns.h"

color.c

@@ -4,6 +4,7 @@
 #include <X11/X.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/extensions/Xrandr.h>
 #include "dat.h"
 #include "fns.h"
 

cursor.c

@@ -3,6 +3,7 @@
 #include <X11/X.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/extensions/Xrandr.h>
 #include "dat.h"
 #include "fns.h"
 

dat.h

@@ -1,5 +1,7 @@
 /* Copyright (c) 1994-1996 David Hogan, see README for licence details */
-
+#ifndef MAX_MONITORS
+#define MAX_MONITORS 8
+#endif
 #ifndef BORDER
 #define BORDER _border
 #endif
@@ -196,3 +198,8 @@ extern int ignore_badwindow;
 /* key.c and event.c share this */
 
 extern int kbLaunch;
+
+/* multimonitor biz */
+
+extern int nmonitors;
+extern XRRMonitorInfo* monitorinfo;

error.c

@@ -5,6 +5,7 @@
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/Xproto.h>
+#include <X11/extensions/Xrandr.h>
 #include "dat.h"
 #include "fns.h"
 

event.c

@@ -12,6 +12,7 @@
 #include <X11/Xutil.h>
 #include <X11/Xatom.h>
 #include <X11/extensions/shape.h>
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #include "dat.h"
 #include "fns.h"
@@ -19,6 +20,7 @@
 
 void mainloop(int shape_event) {
   XEvent ev;
+  int i;
 
   for (;;) {
     getevent(&ev);
@@ -37,6 +39,22 @@ void mainloop(int shape_event) {
 #endif
           fprintf(stderr, "ryudo: unknown ev.type %d\n", ev.type);
         break;
+      /* XRANDR related events; idk what the define for this is */
+      case 89:
+        if (XRRUpdateConfiguration(&ev)) {
+          fetchmonitorinfo();
+          fprintf(stderr, "%d monitors:\n", nmonitors);
+          for (i = 0; i < nmonitors; i++) {
+            fprintf(
+              stderr,
+              "  %d,%d,%d,%d\n",
+              monitorinfo[i].x,
+              monitorinfo[i].y,
+              monitorinfo[i].width,
+              monitorinfo[i].height);
+          }
+        }
+        break;
       case KeyPress:
         keypress(&ev.xkey);
         break;

fns.h

@@ -122,3 +122,7 @@ void dotrace();
 void initcurs();
 
 void ShowEvent(XEvent*);
+
+void fetchmonitorinfo();
+int getmonitorbyclient(Client*);
+int getmonitorbymouse();

grab.c

@@ -4,6 +4,7 @@
 #include <X11/Xos.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/extensions/Xrandr.h>
 #include "dat.h"
 #include "fns.h"
 

key.c

@@ -14,6 +14,7 @@
 #include <X11/Xatom.h>
 #include <X11/keysym.h>
 #include <X11/extensions/shape.h>
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #include "dat.h"
 #include "fns.h"

main.c

@@ -12,6 +12,7 @@
 #ifdef SHAPE
 #include <X11/extensions/shape.h>
 #endif
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #ifdef VIRTNOTIFY
 #include <libnotify/notify.h>
@@ -392,6 +393,9 @@ void initscreen(ScreenInfo* s, int i, int background) {
     s->vis,
     CWBackPixel | CWBorderPixel | CWColormap,
     &attrs);
+
+  XRRSelectInput(dpy, DefaultRootWindow(dpy), RRScreenChangeNotifyMask);
+  fetchmonitorinfo();
 }
 
 ScreenInfo* getscreen(Window w) {

manage.c

@@ -16,6 +16,7 @@
 #include <X11/Xutil.h>
 #include <X11/Xatom.h>
 #include <X11/extensions/shape.h>
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #include "dat.h"
 #include "fns.h"

menu.c

@@ -14,6 +14,7 @@
 #include <X11/X.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
+#include <X11/extensions/Xrandr.h>
 #include "config.h"
 #ifdef VIRTNOTIFY
 #include <libnotify/notify.h>

mkfile

@@ -12,6 +12,7 @@ RIOFILES=\
 	main.$O\
 	manage.$O\
 	menu.$O\
+	monitor.$O\
 
 HFILES=dat.h fns.h
 
@@ -22,7 +23,7 @@ TARG=rio xshove
 # Bug in mk? "$L64 -lXext" gobbles the space, so
 # add trailing slash.
 L64=`[ -d $X11/lib64 ] && echo 64; echo`
-LDFLAGS=-L$X11/lib$L64/ -Llibnotify/ -lnotify -lXext -lX11  $LDFLAGS
+LDFLAGS=-L$X11/lib$L64/ -Llibnotify/ -lnotify -lXext -lX11 -lXrandr $LDFLAGS
 
 <|sh mkriorules.sh
 

monitor.c

@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <X11/Xlib.h>
+#include <X11/extensions/Xrandr.h>
+#include "dat.h"
+#include "fns.h"
+
+int nmonitors = 0;
+XRRMonitorInfo* monitorinfo;
+
+void fetchmonitorinfo() {
+  if (monitorinfo)
+    XRRFreeMonitors(monitorinfo);
+
+  monitorinfo = XRRGetMonitors(dpy, DefaultRootWindow(dpy), 1, &nmonitors);
+}
+
+int getmonitorbyclient(Client* c) {
+  XRRMonitorInfo m;
+  int cx, cy, i, p;
+  cx = c->x + c->dx / 2;
+  cy = c->y + c->dy / 2;
+
+  p = 0;
+
+  for (i = 0; i < nmonitors; i++) {
+    m = monitorinfo[i];
+    if (cx >= m.x && cx < m.x + m.width && cy >= m.y && cy < m.y + m.height) {
+      return i;
+    }
+
+    if (m.primary) {
+      p = i;
+    }
+  }
+
+  /* if center is not within any window, return primary */
+  return p;
+}
+
+int getmonitorbymouse() {
+  Window w;
+  int x, y, i;
+  unsigned int mask;
+  XRRMonitorInfo m;
+
+  XQueryPointer(dpy, DefaultRootWindow(dpy), &w, &w, &x, &y, &x, &y, &mask);
+  for (i = 0; i < nmonitors; i++) {
+    m = monitorinfo[i];
+    if (x >= m.x && x < m.x + m.width && y >= m.y && y < m.y + m.height) {
+      return i;
+    }
+  }
+  /* should never reach here, but return first monitor if we do */
+  return 0;
+}