blob: 16d630f58bb491cbf5394960ef5a8e90f30f4b4f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/char/selection.c
3 *
4 * This module exports the functions:
5 *
6 * 'int set_selection(struct tiocl_selection __user *, struct tty_struct *)'
7 * 'void clear_selection(void)'
8 * 'int paste_selection(struct tty_struct *)'
9 * 'int sel_loadlut(char __user *)'
10 *
11 * Now that /dev/vcs exists, most of this can disappear again.
12 */
13
14#include <linux/module.h>
15#include <linux/tty.h>
16#include <linux/sched.h>
17#include <linux/mm.h>
18#include <linux/slab.h>
19#include <linux/types.h>
20
21#include <asm/uaccess.h>
22
23#include <linux/vt_kern.h>
24#include <linux/consolemap.h>
25#include <linux/selection.h>
26#include <linux/tiocl.h>
27#include <linux/console.h>
28
29/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
30#define isspace(c) ((c) == ' ')
31
32extern void poke_blanked_console(void);
33
34/* Variables for selection control. */
35/* Use a dynamic buffer, instead of static (Dec 1994) */
36struct vc_data *sel_cons; /* must not be disallocated */
37static volatile int sel_start = -1; /* cleared by clear_selection */
38static int sel_end;
39static int sel_buffer_lth;
40static char *sel_buffer;
41
42/* clear_selection, highlight and highlight_pointer can be called
43 from interrupt (via scrollback/front) */
44
45/* set reverse video on characters s-e of console with selection. */
46static inline void highlight(const int s, const int e)
47{
48 invert_screen(sel_cons, s, e-s+2, 1);
49}
50
51/* use complementary color to show the pointer */
52static inline void highlight_pointer(const int where)
53{
54 complement_pos(sel_cons, where);
55}
56
57static unsigned char
58sel_pos(int n)
59{
60 return inverse_translate(sel_cons, screen_glyph(sel_cons, n));
61}
62
63/* remove the current selection highlight, if any,
64 from the console holding the selection. */
65void
66clear_selection(void) {
67 highlight_pointer(-1); /* hide the pointer */
68 if (sel_start != -1) {
69 highlight(sel_start, sel_end);
70 sel_start = -1;
71 }
72}
73
74/*
75 * User settable table: what characters are to be considered alphabetic?
76 * 256 bits
77 */
78static u32 inwordLut[8]={
79 0x00000000, /* control chars */
80 0x03FF0000, /* digits */
81 0x87FFFFFE, /* uppercase and '_' */
82 0x07FFFFFE, /* lowercase */
83 0x00000000,
84 0x00000000,
85 0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
86 0xFF7FFFFF /* latin-1 accented letters, not division sign */
87};
88
89static inline int inword(const unsigned char c) {
90 return ( inwordLut[c>>5] >> (c & 0x1F) ) & 1;
91}
92
93/* set inwordLut contents. Invoked by ioctl(). */
94int sel_loadlut(char __user *p)
95{
96 return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 0;
97}
98
99/* does screen address p correspond to character at LH/RH edge of screen? */
100static inline int atedge(const int p, int size_row)
101{
102 return (!(p % size_row) || !((p + 2) % size_row));
103}
104
105/* constrain v such that v <= u */
106static inline unsigned short limit(const unsigned short v, const unsigned short u)
107{
108 return (v > u) ? u : v;
109}
110
111/* set the current selection. Invoked by ioctl() or by kernel code. */
112int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
113{
114 struct vc_data *vc = vc_cons[fg_console].d;
115 int sel_mode, new_sel_start, new_sel_end, spc;
116 char *bp, *obp;
117 int i, ps, pe;
118
119 poke_blanked_console();
120
121 { unsigned short xs, ys, xe, ye;
122
123 if (!access_ok(VERIFY_READ, sel, sizeof(*sel)))
124 return -EFAULT;
125 __get_user(xs, &sel->xs);
126 __get_user(ys, &sel->ys);
127 __get_user(xe, &sel->xe);
128 __get_user(ye, &sel->ye);
129 __get_user(sel_mode, &sel->sel_mode);
130 xs--; ys--; xe--; ye--;
131 xs = limit(xs, vc->vc_cols - 1);
132 ys = limit(ys, vc->vc_rows - 1);
133 xe = limit(xe, vc->vc_cols - 1);
134 ye = limit(ye, vc->vc_rows - 1);
135 ps = ys * vc->vc_size_row + (xs << 1);
136 pe = ye * vc->vc_size_row + (xe << 1);
137
138 if (sel_mode == TIOCL_SELCLEAR) {
139 /* useful for screendump without selection highlights */
140 clear_selection();
141 return 0;
142 }
143
144 if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) {
145 mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys);
146 return 0;
147 }
148 }
149
150 if (ps > pe) /* make sel_start <= sel_end */
151 {
152 int tmp = ps;
153 ps = pe;
154 pe = tmp;
155 }
156
157 if (sel_cons != vc_cons[fg_console].d) {
158 clear_selection();
159 sel_cons = vc_cons[fg_console].d;
160 }
161
162 switch (sel_mode)
163 {
164 case TIOCL_SELCHAR: /* character-by-character selection */
165 new_sel_start = ps;
166 new_sel_end = pe;
167 break;
168 case TIOCL_SELWORD: /* word-by-word selection */
169 spc = isspace(sel_pos(ps));
170 for (new_sel_start = ps; ; ps -= 2)
171 {
172 if ((spc && !isspace(sel_pos(ps))) ||
173 (!spc && !inword(sel_pos(ps))))
174 break;
175 new_sel_start = ps;
176 if (!(ps % vc->vc_size_row))
177 break;
178 }
179 spc = isspace(sel_pos(pe));
180 for (new_sel_end = pe; ; pe += 2)
181 {
182 if ((spc && !isspace(sel_pos(pe))) ||
183 (!spc && !inword(sel_pos(pe))))
184 break;
185 new_sel_end = pe;
186 if (!((pe + 2) % vc->vc_size_row))
187 break;
188 }
189 break;
190 case TIOCL_SELLINE: /* line-by-line selection */
191 new_sel_start = ps - ps % vc->vc_size_row;
192 new_sel_end = pe + vc->vc_size_row
193 - pe % vc->vc_size_row - 2;
194 break;
195 case TIOCL_SELPOINTER:
196 highlight_pointer(pe);
197 return 0;
198 default:
199 return -EINVAL;
200 }
201
202 /* remove the pointer */
203 highlight_pointer(-1);
204
205 /* select to end of line if on trailing space */
206 if (new_sel_end > new_sel_start &&
207 !atedge(new_sel_end, vc->vc_size_row) &&
208 isspace(sel_pos(new_sel_end))) {
209 for (pe = new_sel_end + 2; ; pe += 2)
210 if (!isspace(sel_pos(pe)) ||
211 atedge(pe, vc->vc_size_row))
212 break;
213 if (isspace(sel_pos(pe)))
214 new_sel_end = pe;
215 }
216 if (sel_start == -1) /* no current selection */
217 highlight(new_sel_start, new_sel_end);
218 else if (new_sel_start == sel_start)
219 {
220 if (new_sel_end == sel_end) /* no action required */
221 return 0;
222 else if (new_sel_end > sel_end) /* extend to right */
223 highlight(sel_end + 2, new_sel_end);
224 else /* contract from right */
225 highlight(new_sel_end + 2, sel_end);
226 }
227 else if (new_sel_end == sel_end)
228 {
229 if (new_sel_start < sel_start) /* extend to left */
230 highlight(new_sel_start, sel_start - 2);
231 else /* contract from left */
232 highlight(sel_start, new_sel_start - 2);
233 }
234 else /* some other case; start selection from scratch */
235 {
236 clear_selection();
237 highlight(new_sel_start, new_sel_end);
238 }
239 sel_start = new_sel_start;
240 sel_end = new_sel_end;
241
242 /* Allocate a new buffer before freeing the old one ... */
243 bp = kmalloc((sel_end-sel_start)/2+1, GFP_KERNEL);
244 if (!bp) {
245 printk(KERN_WARNING "selection: kmalloc() failed\n");
246 clear_selection();
247 return -ENOMEM;
248 }
249 if (sel_buffer)
250 kfree(sel_buffer);
251 sel_buffer = bp;
252
253 obp = bp;
254 for (i = sel_start; i <= sel_end; i += 2) {
255 *bp = sel_pos(i);
256 if (!isspace(*bp++))
257 obp = bp;
258 if (! ((i + 2) % vc->vc_size_row)) {
259 /* strip trailing blanks from line and add newline,
260 unless non-space at end of line. */
261 if (obp != bp) {
262 bp = obp;
263 *bp++ = '\r';
264 }
265 obp = bp;
266 }
267 }
268 sel_buffer_lth = bp - sel_buffer;
269 return 0;
270}
271
272/* Insert the contents of the selection buffer into the
273 * queue of the tty associated with the current console.
274 * Invoked by ioctl().
275 */
276int paste_selection(struct tty_struct *tty)
277{
278 struct vc_data *vc = (struct vc_data *)tty->driver_data;
279 int pasted = 0, count;
280 struct tty_ldisc *ld;
281 DECLARE_WAITQUEUE(wait, current);
282
283 acquire_console_sem();
284 poke_blanked_console();
285 release_console_sem();
286
287 ld = tty_ldisc_ref_wait(tty);
288
289 add_wait_queue(&vc->paste_wait, &wait);
290 while (sel_buffer && sel_buffer_lth > pasted) {
291 set_current_state(TASK_INTERRUPTIBLE);
292 if (test_bit(TTY_THROTTLED, &tty->flags)) {
293 schedule();
294 continue;
295 }
296 count = sel_buffer_lth - pasted;
297 count = min(count, tty->ldisc.receive_room(tty));
298 tty->ldisc.receive_buf(tty, sel_buffer + pasted, NULL, count);
299 pasted += count;
300 }
301 remove_wait_queue(&vc->paste_wait, &wait);
302 current->state = TASK_RUNNING;
303
304 tty_ldisc_deref(ld);
305 return 0;
306}