1#include <linux/slab.h> /* for kmalloc */
2#include <linux/consolemap.h>
3#include <linux/interrupt.h>
4#include <linux/sched.h>
5#include <linux/device.h> /* for dev_warn */
6#include <linux/selection.h>
7#include <linux/workqueue.h>
8#include <linux/tty.h>
9#include <linux/tty_flip.h>
10#include <asm/cmpxchg.h>
11
12#include "speakup.h"
13
14/* ------ cut and paste ----- */
15/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
16#define ishardspace(c)      ((c) == ' ')
17
18unsigned short spk_xs, spk_ys, spk_xe, spk_ye; /* our region points */
19
20/* Variables for selection control. */
21/* must not be deallocated */
22struct vc_data *spk_sel_cons;
23/* cleared by clear_selection */
24static int sel_start = -1;
25static int sel_end;
26static int sel_buffer_lth;
27static char *sel_buffer;
28
29static unsigned char sel_pos(int n)
30{
31	return inverse_translate(spk_sel_cons,
32		screen_glyph(spk_sel_cons, n), 0);
33}
34
35void speakup_clear_selection(void)
36{
37	sel_start = -1;
38}
39
40/* does screen address p correspond to character at LH/RH edge of screen? */
41static int atedge(const int p, int size_row)
42{
43	return !(p % size_row) || !((p + 2) % size_row);
44}
45
46/* constrain v such that v <= u */
47static unsigned short limit(const unsigned short v, const unsigned short u)
48{
49	return (v > u) ? u : v;
50}
51
52int speakup_set_selection(struct tty_struct *tty)
53{
54	int new_sel_start, new_sel_end;
55	char *bp, *obp;
56	int i, ps, pe;
57	struct vc_data *vc = vc_cons[fg_console].d;
58
59	spk_xs = limit(spk_xs, vc->vc_cols - 1);
60	spk_ys = limit(spk_ys, vc->vc_rows - 1);
61	spk_xe = limit(spk_xe, vc->vc_cols - 1);
62	spk_ye = limit(spk_ye, vc->vc_rows - 1);
63	ps = spk_ys * vc->vc_size_row + (spk_xs << 1);
64	pe = spk_ye * vc->vc_size_row + (spk_xe << 1);
65
66	if (ps > pe) {
67		/* make sel_start <= sel_end */
68		int tmp = ps;
69
70		ps = pe;
71		pe = tmp;
72	}
73
74	if (spk_sel_cons != vc_cons[fg_console].d) {
75		speakup_clear_selection();
76		spk_sel_cons = vc_cons[fg_console].d;
77		dev_warn(tty->dev,
78			"Selection: mark console not the same as cut\n");
79		return -EINVAL;
80	}
81
82	new_sel_start = ps;
83	new_sel_end = pe;
84
85	/* select to end of line if on trailing space */
86	if (new_sel_end > new_sel_start &&
87	    !atedge(new_sel_end, vc->vc_size_row) &&
88	    ishardspace(sel_pos(new_sel_end))) {
89		for (pe = new_sel_end + 2; ; pe += 2)
90			if (!ishardspace(sel_pos(pe)) ||
91			    atedge(pe, vc->vc_size_row))
92				break;
93		if (ishardspace(sel_pos(pe)))
94			new_sel_end = pe;
95	}
96	if ((new_sel_start == sel_start) && (new_sel_end == sel_end))
97		return 0; /* no action required */
98
99	sel_start = new_sel_start;
100	sel_end = new_sel_end;
101	/* Allocate a new buffer before freeing the old one ... */
102	bp = kmalloc((sel_end-sel_start)/2+1, GFP_ATOMIC);
103	if (!bp) {
104		speakup_clear_selection();
105		return -ENOMEM;
106	}
107	kfree(sel_buffer);
108	sel_buffer = bp;
109
110	obp = bp;
111	for (i = sel_start; i <= sel_end; i += 2) {
112		*bp = sel_pos(i);
113		if (!ishardspace(*bp++))
114			obp = bp;
115		if (!((i + 2) % vc->vc_size_row)) {
116			/* strip trailing blanks from line and add newline,
117			   unless non-space at end of line. */
118			if (obp != bp) {
119				bp = obp;
120				*bp++ = '\r';
121			}
122			obp = bp;
123		}
124	}
125	sel_buffer_lth = bp - sel_buffer;
126	return 0;
127}
128
129struct speakup_paste_work {
130	struct work_struct work;
131	struct tty_struct *tty;
132};
133
134static void __speakup_paste_selection(struct work_struct *work)
135{
136	struct speakup_paste_work *spw =
137		container_of(work, struct speakup_paste_work, work);
138	struct tty_struct *tty = xchg(&spw->tty, NULL);
139	struct vc_data *vc = (struct vc_data *) tty->driver_data;
140	int pasted = 0, count;
141	struct tty_ldisc *ld;
142	DECLARE_WAITQUEUE(wait, current);
143
144	ld = tty_ldisc_ref(tty);
145	if (!ld)
146		goto tty_unref;
147	tty_buffer_lock_exclusive(&vc->port);
148
149	add_wait_queue(&vc->paste_wait, &wait);
150	while (sel_buffer && sel_buffer_lth > pasted) {
151		set_current_state(TASK_INTERRUPTIBLE);
152		if (test_bit(TTY_THROTTLED, &tty->flags)) {
153			schedule();
154			continue;
155		}
156		count = sel_buffer_lth - pasted;
157		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
158					      count);
159		pasted += count;
160	}
161	remove_wait_queue(&vc->paste_wait, &wait);
162	__set_current_state(TASK_RUNNING);
163
164	tty_buffer_unlock_exclusive(&vc->port);
165	tty_ldisc_deref(ld);
166tty_unref:
167	tty_kref_put(tty);
168}
169
170static struct speakup_paste_work speakup_paste_work = {
171	.work = __WORK_INITIALIZER(speakup_paste_work.work,
172				   __speakup_paste_selection)
173};
174
175int speakup_paste_selection(struct tty_struct *tty)
176{
177	if (cmpxchg(&speakup_paste_work.tty, NULL, tty) != NULL)
178		return -EBUSY;
179
180	tty_kref_get(tty);
181	schedule_work_on(WORK_CPU_UNBOUND, &speakup_paste_work.work);
182	return 0;
183}
184
185void speakup_cancel_paste(void)
186{
187	cancel_work_sync(&speakup_paste_work.work);
188	tty_kref_put(speakup_paste_work.tty);
189}
190