XIQueryDevice.c revision 44584a44 
1/*
2 * Copyright © 2009 Red Hat, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 */
24
25#if HAVE_CONFIG_H
26#include <config.h>
27#endif
28
29#include <stdint.h>
30#include <X11/Xlibint.h>
31#include <X11/extensions/XI2proto.h>
32#include <X11/extensions/XInput2.h>
33#include <X11/extensions/extutil.h>
34#include "XIint.h"
35
36extern int copy_classes(XIDeviceInfo* to, xXIAnyInfo* from, int *nclasses);
37extern int size_classes(xXIAnyInfo* from, int nclasses);
38
39XIDeviceInfo*
40XIQueryDevice(Display *dpy, int deviceid, int *ndevices_return)
41{
42    XIDeviceInfo        *info = NULL;
43    xXIQueryDeviceReq   *req;
44    xXIQueryDeviceReply reply;
45    char                *ptr;
46    int                 i;
47    char                *buf;
48
49    XExtDisplayInfo *extinfo = XInput_find_display(dpy);
50
51    LockDisplay(dpy);
52    if (_XiCheckExtInit(dpy, XInput_2_0, extinfo) == -1)
53        goto error_unlocked;
54
55    GetReq(XIQueryDevice, req);
56    req->reqType  = extinfo->codes->major_opcode;
57    req->ReqType  = X_XIQueryDevice;
58    req->deviceid = deviceid;
59
60    if (!_XReply(dpy, (xReply*) &reply, 0, xFalse))
61        goto error;
62
63    *ndevices_return = reply.num_devices;
64    info = Xmalloc((reply.num_devices + 1) * sizeof(XIDeviceInfo));
65    if (!info)
66        goto error;
67
68    buf = Xmalloc(reply.length * 4);
69    _XRead(dpy, buf, reply.length * 4);
70    ptr = buf;
71
72    /* info is a null-terminated array */
73    info[reply.num_devices].name = NULL;
74
75    for (i = 0; i < reply.num_devices; i++)
76    {
77        int             nclasses;
78        size_t          sz;
79        XIDeviceInfo    *lib = &info[i];
80        xXIDeviceInfo   *wire = (xXIDeviceInfo*)ptr;
81
82        lib->deviceid    = wire->deviceid;
83        lib->use         = wire->use;
84        lib->attachment  = wire->attachment;
85        lib->enabled     = wire->enabled;
86        nclasses         = wire->num_classes;
87
88        ptr += sizeof(xXIDeviceInfo);
89
90        lib->name = Xcalloc(wire->name_len + 1, 1);
91        strncpy(lib->name, ptr, wire->name_len);
92        ptr += ((wire->name_len + 3)/4) * 4;
93
94        sz = size_classes((xXIAnyInfo*)ptr, nclasses);
95        lib->classes = Xmalloc(sz);
96        ptr += copy_classes(lib, (xXIAnyInfo*)ptr, &nclasses);
97        /* We skip over unused classes */
98        lib->num_classes = nclasses;
99    }
100
101    Xfree(buf);
102    UnlockDisplay(dpy);
103    SyncHandle();
104    return info;
105
106error:
107    UnlockDisplay(dpy);
108error_unlocked:
109    SyncHandle();
110    *ndevices_return = -1;
111    return NULL;
112}
113
114void
115XIFreeDeviceInfo(XIDeviceInfo* info)
116{
117    XIDeviceInfo *ptr = info;
118    while(ptr->name)
119    {
120        Xfree(ptr->classes);
121        Xfree(ptr->name);
122        ptr++;
123    }
124    Xfree(info);
125}
126