src/tmd.c

   1 /* gcc -o part2 `pkg-config --cflags --libs xi` part2.c */
   2 #include <stdio.h>
   3 #include <string.h>
   4 #include <stdlib.h>
   5 #include <unistd.h>
   6 #include <X11/Xlib.h>
   7 #include <X11/extensions/XInput2.h>
   8
   9 #define MD_PREFIX "TUIO "
  10
  11 typedef struct _attach_info {
  12     struct _attach_info *next;
  13     int slaveid;
  14     char *m_name;
  15 } AttachInfo, *AttachInfoPtr;
  16
  17 static AttachInfo ais;
  18
  19 /**
  20  * Creates a new master device.
  21  */
  22 int create_master(Display* dpy, char* name)
  23 {
  24     XIAddMasterInfo c;
  25
  26     c.type = XIAddMaster;
  27     c.name = name;
  28     c.send_core = 1;
  29     c.enable = 1;
  30
  31     return XIChangeHierarchy(dpy, (XIAnyHierarchyChangeInfo*)&c, 1);
  32 }
  33
  34 /**
  35  * Attaches a slave device to a master device.
  36  */
  37 int change_attachment(Display* dpy, int slaveid, int masterid)
  38 {
  39     XIAttachSlaveInfo c;
  40
  41     c.type = XIAttachSlave;
  42     c.deviceid = slaveid;
  43     c.new_master = masterid;
  44
  45     return XIChangeHierarchy(dpy, (XIAnyHierarchyChangeInfo*)&c, 1);
  46 }
  47
  48 /**
  49  * Listens for the creation of slave and master devices.  When a new slave
  50  * device is found, a new master device will be created and attached to
  51  * when the message for the new master device comes back around.
  52  */
  53 void listen(Display *dpy, int xi_opcode)
  54 {
  55     int num_devices;
  56     unsigned char hmask[2] = { 0, 0 };
  57     char *m_name, *s_name;
  58     XIEvent ev;
  59     XIEventMask evmask_h;
  60     AttachInfoPtr ai;
  61
  62     Cursor m_cur;
  63     m_cur = XCreateFontCursor(dpy, 88);
  64     if (m_cur == BadAlloc || m_cur == BadValue) {
  65         printf("Unable to create cursor\n");
  66     }
  67
  68     evmask_h.mask = hmask;
  69     evmask_h.mask_len = sizeof(hmask);
  70     evmask_h.deviceid = XIAllDevices;
  71     XISetMask(hmask, XI_HierarchyChanged);
  72     //XFlush(dpy);
  73
  74     XISelectEvents(dpy, DefaultRootWindow(dpy), &evmask_h, 1);
  75
  76     while (1) {
  77         XNextEvent(dpy, (XIEvent *)&ev);
  78         if (ev.type != GenericEvent ||
  79                 ev.extension != xi_opcode)
  80             continue;
  81
  82         if (ev.evtype == XI_HierarchyChanged) {
  83             int i;
  84             XIHierarchyEvent *event = (XIHierarchyEvent*)&ev;
  85             printf("Hierarchy Event.\n");
  86
  87             /* Look for slave or masters added */
  88             if (event->flags & XISlaveAdded) {
  89                 printf("Slave added\n");
  90                 for (i=0; i < event->num_info; i++) {
  91                     if(event->info[i].flags & XISlaveAdded) {
  92                         s_name = XIQueryDevice(dpy, event->info[i].deviceid, &num_devices)->name;
  93
  94                         /* This is a hack.  Xtst slave devices are created and
  95                          * attached to each new master device.  If we were to
  96                          * actually create a new master device for this device
  97                          * we would end up with a recurring creation of
  98                          * master devices and slave devices. */
  99                         if (strstr(s_name, "Xtst")) continue;
 100
 101                         asprintf(&m_name, MD_PREFIX"%s", s_name);
 102                         create_master(dpy, m_name);
 103                         free(m_name);
 104
 105                         ai = malloc(sizeof(AttachInfo));
 106                         ai->next = ais.next;
 107                         ais.next = ai;
 108
 109                         asprintf(&ai->m_name, MD_PREFIX"%s pointer", s_name);
 110                         ai->slaveid = event->info[i].deviceid;
 111                     }
 112                 }
 113             } else if (event->flags & XIMasterAdded) {
 114                 printf("Master added\n");
 115
 116                 for (i=0; i < event->num_info; i++) {
 117                     if(event->info[i].flags & XIMasterAdded) {
 118
 119                         m_name = XIQueryDevice(dpy, event->info[i].deviceid, &num_devices)->name;
 120
 121                         ai = ais.next;
 122                         while (ai != NULL) {
 123                             if (strcmp(ai->m_name, m_name) == 0) {
 124                                 printf("  New Master: %d %s\n", event->info[i].deviceid,
 125                                         m_name);
 126                                 change_attachment(dpy, ai->slaveid, event->info[i].deviceid);
 127                                 XIDefineCursor(dpy, event->info[i].deviceid,
 128                                                DefaultRootWindow(dpy), m_cur);
 129                             }
 130                             ai = ai->next;
 131                         }
 132                     }
 133                 }
 134             }
 135         }
 136     }
 137 }
 138
 139 int main (int argc, char **argv)
 140 {
 141     Display *dpy;
 142     int xi_opcode, event, error;
 143     int major, minor;
 144     int ret;
 145
 146     ais.next = NULL;
 147
 148     /* Open X display */
 149     dpy = XOpenDisplay(NULL);
 150     if (!dpy) {
 151         printf("Failed to open display.\n");
 152         return -1;
 153     }
 154
 155     /* Make sure the X Input extension is available */
 156     if (!XQueryExtension(dpy, "XInputExtension", &xi_opcode, &event, &error)) {
 157         printf("X Input extension not available.\n");
 158         return -1;
 159     }
 160
 161     /* Check XI version, need 2.0 */
 162     major = 2;
 163     minor = 0;
 164     ret = XIQueryVersion(dpy, &major, &minor);
 165     if (ret == BadRequest) {
 166         printf("XInput 2.0 not supported.  Server supports %i.%i.\n", major, minor);
 167         return -1;
 168     }
 169
 170     listen(dpy, xi_opcode);
 171
 172     XCloseDisplay(dpy);
 173     return 0;
 174 }