aboutsummaryrefslogtreecommitdiff
path: root/drivers/staging/speakup/selection.c
blob: ca04d3669acca2cef588d8e2d61e1b858debbc36 (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
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
#include <linux/slab.h> /* for kmalloc */
#include <linux/consolemap.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/device.h> /* for dev_warn */
#include <linux/selection.h>
#include <linux/workqueue.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <asm/cmpxchg.h>

#include "speakup.h"

/* ------ cut and paste ----- */
/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
#define ishardspace(c)      ((c) == ' ')

unsigned short spk_xs, spk_ys, spk_xe, spk_ye; /* our region points */

/* Variables for selection control. */
/* must not be deallocated */
struct vc_data *spk_sel_cons;
/* cleared by clear_selection */
static int sel_start = -1;
static int sel_end;
static int sel_buffer_lth;
static char *sel_buffer;

static unsigned char sel_pos(int n)
{
	return inverse_translate(spk_sel_cons,
		screen_glyph(spk_sel_cons, n), 0);
}

void speakup_clear_selection(void)
{
	sel_start = -1;
}

/* does screen address p correspond to character at LH/RH edge of screen? */
static int atedge(const int p, int size_row)
{
	return !(p % size_row) || !((p + 2) % size_row);
}

/* constrain v such that v <= u */
static unsigned short limit(const unsigned short v, const unsigned short u)
{
	return (v > u) ? u : v;
}

int speakup_set_selection(struct tty_struct *tty)
{
	int new_sel_start, new_sel_end;
	char *bp, *obp;
	int i, ps, pe;
	struct vc_data *vc = vc_cons[fg_console].d;

	spk_xs = limit(spk_xs, vc->vc_cols - 1);
	spk_ys = limit(spk_ys, vc->vc_rows - 1);
	spk_xe = limit(spk_xe, vc->vc_cols - 1);
	spk_ye = limit(spk_ye, vc->vc_rows - 1);
	ps = spk_ys * vc->vc_size_row + (spk_xs << 1);
	pe = spk_ye * vc->vc_size_row + (spk_xe << 1);

	if (ps > pe) {
		/* make sel_start <= sel_end */
		int tmp = ps;
		ps = pe;
		pe = tmp;
	}

	if (spk_sel_cons != vc_cons[fg_console].d) {
		speakup_clear_selection();
		spk_sel_cons = vc_cons[fg_console].d;
		dev_warn(tty->dev,
			"Selection: mark console not the same as cut\n");
		return -EINVAL;
	}

	new_sel_start = ps;
	new_sel_end = pe;

	/* select to end of line if on trailing space */
	if (new_sel_end > new_sel_start &&
	    !atedge(new_sel_end, vc->vc_size_row) &&
	    ishardspace(sel_pos(new_sel_end))) {
		for (pe = new_sel_end + 2; ; pe += 2)
			if (!ishardspace(sel_pos(pe)) ||
			    atedge(pe, vc->vc_size_row))
				break;
		if (ishardspace(sel_pos(pe)))
			new_sel_end = pe;
	}
	if ((new_sel_start == sel_start) && (new_sel_end == sel_end))
		return 0; /* no action required */

	sel_start = new_sel_start;
	sel_end = new_sel_end;
	/* Allocate a new buffer before freeing the old one ... */
	bp = kmalloc((sel_end-sel_start)/2+1, GFP_ATOMIC);
	if (!bp) {
		speakup_clear_selection();
		return -ENOMEM;
	}
	kfree(sel_buffer);
	sel_buffer = bp;

	obp = bp;
	for (i = sel_start; i <= sel_end; i += 2) {
		*bp = sel_pos(i);
		if (!ishardspace(*bp++))
			obp = bp;
		if (!((i + 2) % vc->vc_size_row)) {
			/* strip trailing blanks from line and add newline,
			   unless non-space at end of line. */
			if (obp != bp) {
				bp = obp;
				*bp++ = '\r';
			}
			obp = bp;
		}
	}
	sel_buffer_lth = bp - sel_buffer;
	return 0;
}

struct speakup_paste_work {
	struct work_struct work;
	struct tty_struct *tty;
};

static void __speakup_paste_selection(struct work_struct *work)
{
	struct speakup_paste_work *spw =
		container_of(work, struct speakup_paste_work, work);
	struct tty_struct *tty = xchg(&spw->tty, NULL);
	struct vc_data *vc = (struct vc_data *) tty->driver_data;
	int pasted = 0, count;
	struct tty_ldisc *ld;
	DECLARE_WAITQUEUE(wait, current);

	ld = tty_ldisc_ref_wait(tty);
	tty_buffer_lock_exclusive(&vc->port);

	add_wait_queue(&vc->paste_wait, &wait);
	while (sel_buffer && sel_buffer_lth > pasted) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (test_bit(TTY_THROTTLED, &tty->flags)) {
			schedule();
			continue;
		}
		count = sel_buffer_lth - pasted;
		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
					      count);
		pasted += count;
	}
	remove_wait_queue(&vc->paste_wait, &wait);
	current->state = TASK_RUNNING;

	tty_buffer_unlock_exclusive(&vc->port);
	tty_ldisc_deref(ld);
	tty_kref_put(tty);
}

static struct speakup_paste_work speakup_paste_work = {
	.work = __WORK_INITIALIZER(speakup_paste_work.work,
				   __speakup_paste_selection)
};

int speakup_paste_selection(struct tty_struct *tty)
{
	if (cmpxchg(&speakup_paste_work.tty, NULL, tty) != NULL)
		return -EBUSY;

	tty_kref_get(tty);
	schedule_work_on(WORK_CPU_UNBOUND, &speakup_paste_work.work);
	return 0;
}

void speakup_cancel_paste(void)
{
	cancel_work_sync(&speakup_paste_work.work);
	tty_kref_put(speakup_paste_work.tty);
}