• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 <linux/atomic.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 
18 unsigned short spk_xs, spk_ys, spk_xe, spk_ye; /* our region points */
19 
20 /* Variables for selection control. */
21 /* must not be deallocated */
22 struct vc_data *spk_sel_cons;
23 /* cleared by clear_selection */
24 static int sel_start = -1;
25 static int sel_end;
26 static int sel_buffer_lth;
27 static char *sel_buffer;
28 
sel_pos(int n)29 static unsigned char sel_pos(int n)
30 {
31 	return inverse_translate(spk_sel_cons,
32 		screen_glyph(spk_sel_cons, n), 0);
33 }
34 
speakup_clear_selection(void)35 void 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? */
atedge(const int p,int size_row)41 static 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 */
limit(const unsigned short v,const unsigned short u)47 static unsigned short limit(const unsigned short v, const unsigned short u)
48 {
49 	return (v > u) ? u : v;
50 }
51 
speakup_set_selection(struct tty_struct * tty)52 int 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 			 */
119 			if (obp != bp) {
120 				bp = obp;
121 				*bp++ = '\r';
122 			}
123 			obp = bp;
124 		}
125 	}
126 	sel_buffer_lth = bp - sel_buffer;
127 	return 0;
128 }
129 
130 struct speakup_paste_work {
131 	struct work_struct work;
132 	struct tty_struct *tty;
133 };
134 
__speakup_paste_selection(struct work_struct * work)135 static void __speakup_paste_selection(struct work_struct *work)
136 {
137 	struct speakup_paste_work *spw =
138 		container_of(work, struct speakup_paste_work, work);
139 	struct tty_struct *tty = xchg(&spw->tty, NULL);
140 	struct vc_data *vc = (struct vc_data *) tty->driver_data;
141 	int pasted = 0, count;
142 	struct tty_ldisc *ld;
143 	DECLARE_WAITQUEUE(wait, current);
144 
145 	ld = tty_ldisc_ref(tty);
146 	if (!ld)
147 		goto tty_unref;
148 	tty_buffer_lock_exclusive(&vc->port);
149 
150 	add_wait_queue(&vc->paste_wait, &wait);
151 	while (sel_buffer && sel_buffer_lth > pasted) {
152 		set_current_state(TASK_INTERRUPTIBLE);
153 		if (tty_throttled(tty)) {
154 			schedule();
155 			continue;
156 		}
157 		count = sel_buffer_lth - pasted;
158 		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
159 					      count);
160 		pasted += count;
161 	}
162 	remove_wait_queue(&vc->paste_wait, &wait);
163 	__set_current_state(TASK_RUNNING);
164 
165 	tty_buffer_unlock_exclusive(&vc->port);
166 	tty_ldisc_deref(ld);
167 tty_unref:
168 	tty_kref_put(tty);
169 }
170 
171 static struct speakup_paste_work speakup_paste_work = {
172 	.work = __WORK_INITIALIZER(speakup_paste_work.work,
173 				   __speakup_paste_selection)
174 };
175 
speakup_paste_selection(struct tty_struct * tty)176 int speakup_paste_selection(struct tty_struct *tty)
177 {
178 	if (cmpxchg(&speakup_paste_work.tty, NULL, tty) != NULL)
179 		return -EBUSY;
180 
181 	tty_kref_get(tty);
182 	schedule_work_on(WORK_CPU_UNBOUND, &speakup_paste_work.work);
183 	return 0;
184 }
185 
speakup_cancel_paste(void)186 void speakup_cancel_paste(void)
187 {
188 	cancel_work_sync(&speakup_paste_work.work);
189 	tty_kref_put(speakup_paste_work.tty);
190 }
191