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/selection.h>
6 
7 #include "speakup.h"
8 
9 /* ------ cut and paste ----- */
10 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
11 #define ishardspace(c)      ((c) == ' ')
12 
13 unsigned short xs, ys, xe, ye; /* our region points */
14 
15 /* Variables for selection control. */
16 /* must not be disallocated */
17 struct vc_data *spk_sel_cons;
18 /* cleared by clear_selection */
19 static int sel_start = -1;
20 static int sel_end;
21 static int sel_buffer_lth;
22 static char *sel_buffer;
23 
sel_pos(int n)24 static unsigned char sel_pos(int n)
25 {
26 	return inverse_translate(spk_sel_cons,
27 		screen_glyph(spk_sel_cons, n), 0);
28 }
29 
speakup_clear_selection(void)30 void speakup_clear_selection(void)
31 {
32 	sel_start = -1;
33 }
34 
35 /* does screen address p correspond to character at LH/RH edge of screen? */
atedge(const int p,int size_row)36 static int atedge(const int p, int size_row)
37 {
38 	return !(p % size_row) || !((p + 2) % size_row);
39 }
40 
41 /* constrain v such that v <= u */
limit(const unsigned short v,const unsigned short u)42 static unsigned short limit(const unsigned short v, const unsigned short u)
43 {
44 	return (v > u) ? u : v;
45 }
46 
speakup_set_selection(struct tty_struct * tty)47 int speakup_set_selection(struct tty_struct *tty)
48 {
49 	int new_sel_start, new_sel_end;
50 	char *bp, *obp;
51 	int i, ps, pe;
52 	struct vc_data *vc = vc_cons[fg_console].d;
53 
54 	xs = limit(xs, vc->vc_cols - 1);
55 	ys = limit(ys, vc->vc_rows - 1);
56 	xe = limit(xe, vc->vc_cols - 1);
57 	ye = limit(ye, vc->vc_rows - 1);
58 	ps = ys * vc->vc_size_row + (xs << 1);
59 	pe = ye * vc->vc_size_row + (xe << 1);
60 
61 	if (ps > pe) {
62 		/* make sel_start <= sel_end */
63 		int tmp = ps;
64 		ps = pe;
65 		pe = tmp;
66 	}
67 
68 	if (spk_sel_cons != vc_cons[fg_console].d) {
69 		speakup_clear_selection();
70 		spk_sel_cons = vc_cons[fg_console].d;
71 		printk(KERN_WARNING
72 			"Selection: mark console not the same as cut\n");
73 		return -EINVAL;
74 	}
75 
76 	new_sel_start = ps;
77 	new_sel_end = pe;
78 
79 	/* select to end of line if on trailing space */
80 	if (new_sel_end > new_sel_start &&
81 	    !atedge(new_sel_end, vc->vc_size_row) &&
82 	    ishardspace(sel_pos(new_sel_end))) {
83 		for (pe = new_sel_end + 2; ; pe += 2)
84 			if (!ishardspace(sel_pos(pe)) ||
85 			    atedge(pe, vc->vc_size_row))
86 				break;
87 		if (ishardspace(sel_pos(pe)))
88 			new_sel_end = pe;
89 	}
90 	if ((new_sel_start == sel_start) && (new_sel_end == sel_end))
91 		return 0; /* no action required */
92 
93 	sel_start = new_sel_start;
94 	sel_end = new_sel_end;
95 	/* Allocate a new buffer before freeing the old one ... */
96 	bp = kmalloc((sel_end-sel_start)/2+1, GFP_ATOMIC);
97 	if (!bp) {
98 		printk(KERN_WARNING "selection: kmalloc() failed\n");
99 		speakup_clear_selection();
100 		return -ENOMEM;
101 	}
102 	kfree(sel_buffer);
103 	sel_buffer = bp;
104 
105 	obp = bp;
106 	for (i = sel_start; i <= sel_end; i += 2) {
107 		*bp = sel_pos(i);
108 		if (!ishardspace(*bp++))
109 			obp = bp;
110 		if (!((i + 2) % vc->vc_size_row)) {
111 			/* strip trailing blanks from line and add newline,
112 			   unless non-space at end of line. */
113 			if (obp != bp) {
114 				bp = obp;
115 				*bp++ = '\r';
116 			}
117 			obp = bp;
118 		}
119 	}
120 	sel_buffer_lth = bp - sel_buffer;
121 	return 0;
122 }
123 
124 /* TODO: move to some helper thread, probably.  That'd fix having to check for
125  * in_atomic().  */
speakup_paste_selection(struct tty_struct * tty)126 int speakup_paste_selection(struct tty_struct *tty)
127 {
128 	struct vc_data *vc = (struct vc_data *) tty->driver_data;
129 	int pasted = 0, count;
130 	DECLARE_WAITQUEUE(wait, current);
131 	add_wait_queue(&vc->paste_wait, &wait);
132 	while (sel_buffer && sel_buffer_lth > pasted) {
133 		set_current_state(TASK_INTERRUPTIBLE);
134 		if (test_bit(TTY_THROTTLED, &tty->flags)) {
135 			if (in_atomic())
136 				/* if we are in an interrupt handler, abort */
137 				break;
138 			schedule();
139 			continue;
140 		}
141 		count = sel_buffer_lth - pasted;
142 		count = min_t(int, count, tty->receive_room);
143 		tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted,
144 			0, count);
145 		pasted += count;
146 	}
147 	remove_wait_queue(&vc->paste_wait, &wait);
148 	current->state = TASK_RUNNING;
149 	return 0;
150 }
151 
152