summaryrefslogtreecommitdiff
path: root/src/common.h
blob: e06f7f704d3092b8e27604c8e9b2846badb17717 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
/*****************************************************************************
 *
 * mtdev - Multitouch Protocol Translation Library (MIT license)
 *
 * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
 * Copyright (C) 2010 Canonical Ltd.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 *
 ****************************************************************************/

#ifndef COMMON_H
#define COMMON_H

#include <mtdev-mapping.h>
#include <mtdev-plumbing.h>
#include <malloc.h>
#include <string.h>
#include <errno.h>

#define DIM_FINGER 32
#define DIM2_FINGER (DIM_FINGER * DIM_FINGER)

/* event buffer size (must be a power of two) */
#define DIM_EVENTS 512

/* all bit masks have this type */
typedef unsigned int bitmask_t;

#define BITMASK(x) (1U << (x))
#define BITONES(x) (BITMASK(x) - 1U)
#define GETBIT(m, x) (((m) >> (x)) & 1U)
#define SETBIT(m, x) (m |= BITMASK(x))
#define CLEARBIT(m, x) (m &= ~BITMASK(x))
#define MODBIT(m, x, b) ((b) ? SETBIT(m, x) : CLEARBIT(m, x))

static inline int maxval(int x, int y) { return x > y ? x : y; }
static inline int minval(int x, int y) { return x < y ? x : y; }

static inline int clamp15(int x)
{
	return x < -32767 ? -32767 : x > 32767 ? 32767 : x;
}

/* absolute scale is assumed to fit in 15 bits */
static inline int dist2(int dx, int dy)
{
	dx = clamp15(dx);
	dy = clamp15(dy);
	return dx * dx + dy * dy;
}

/* Count number of bits (Sean Eron Andersson's Bit Hacks) */
static inline int bitcount(unsigned v)
{
	v -= ((v>>1) & 0x55555555);
	v = (v&0x33333333) + ((v>>2) & 0x33333333);
	return (((v + (v>>4)) & 0xF0F0F0F) * 0x1010101) >> 24;
}

/* Return index of first bit [0-31], -1 on zero */
#define firstbit(v) (__builtin_ffs(v) - 1)

/* boost-style foreach bit */
#define foreach_bit(i, m)						\
	for (i = firstbit(m); i >= 0; i = firstbit((m) & (~0U << (i + 1))))

/* robust system ioctl calls */
#define SYSCALL(call) while (((call) == -1) && (errno == EINTR))

#endif