1 /*
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/kbd_kern.h>
24 #include <linux/vt_kern.h>
25 #include <linux/consolemap.h>
26 #include <linux/selection.h>
27 #include <linux/tiocl.h>
28 #include <linux/console.h>
29
30 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
31 #define isspace(c) ((c) == ' ')
32
33 extern void poke_blanked_console(void);
34
35 /* Variables for selection control. */
36 /* Use a dynamic buffer, instead of static (Dec 1994) */
37 struct vc_data *sel_cons; /* must not be deallocated */
38 static int use_unicode;
39 static volatile int sel_start = -1; /* cleared by clear_selection */
40 static int sel_end;
41 static int sel_buffer_lth;
42 static char *sel_buffer;
43
44 /* clear_selection, highlight and highlight_pointer can be called
45 from interrupt (via scrollback/front) */
46
47 /* set reverse video on characters s-e of console with selection. */
highlight(const int s,const int e)48 static inline void highlight(const int s, const int e)
49 {
50 invert_screen(sel_cons, s, e-s+2, 1);
51 }
52
53 /* use complementary color to show the pointer */
highlight_pointer(const int where)54 static inline void highlight_pointer(const int where)
55 {
56 complement_pos(sel_cons, where);
57 }
58
59 static u16
sel_pos(int n)60 sel_pos(int n)
61 {
62 return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
63 use_unicode);
64 }
65
66 /* remove the current selection highlight, if any,
67 from the console holding the selection. */
68 void
clear_selection(void)69 clear_selection(void) {
70 highlight_pointer(-1); /* hide the pointer */
71 if (sel_start != -1) {
72 highlight(sel_start, sel_end);
73 sel_start = -1;
74 }
75 }
76
77 /*
78 * User settable table: what characters are to be considered alphabetic?
79 * 256 bits
80 */
81 static u32 inwordLut[8]={
82 0x00000000, /* control chars */
83 0x03FF0000, /* digits */
84 0x87FFFFFE, /* uppercase and '_' */
85 0x07FFFFFE, /* lowercase */
86 0x00000000,
87 0x00000000,
88 0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
89 0xFF7FFFFF /* latin-1 accented letters, not division sign */
90 };
91
inword(const u16 c)92 static inline int inword(const u16 c) {
93 return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
94 }
95
96 /* set inwordLut contents. Invoked by ioctl(). */
sel_loadlut(char __user * p)97 int sel_loadlut(char __user *p)
98 {
99 return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 0;
100 }
101
102 /* does screen address p correspond to character at LH/RH edge of screen? */
atedge(const int p,int size_row)103 static inline int atedge(const int p, int size_row)
104 {
105 return (!(p % size_row) || !((p + 2) % size_row));
106 }
107
108 /* constrain v such that v <= u */
limit(const unsigned short v,const unsigned short u)109 static inline unsigned short limit(const unsigned short v, const unsigned short u)
110 {
111 return (v > u) ? u : v;
112 }
113
114 /* stores the char in UTF8 and returns the number of bytes used (1-3) */
store_utf8(u16 c,char * p)115 static int store_utf8(u16 c, char *p)
116 {
117 if (c < 0x80) {
118 /* 0******* */
119 p[0] = c;
120 return 1;
121 } else if (c < 0x800) {
122 /* 110***** 10****** */
123 p[0] = 0xc0 | (c >> 6);
124 p[1] = 0x80 | (c & 0x3f);
125 return 2;
126 } else {
127 /* 1110**** 10****** 10****** */
128 p[0] = 0xe0 | (c >> 12);
129 p[1] = 0x80 | ((c >> 6) & 0x3f);
130 p[2] = 0x80 | (c & 0x3f);
131 return 3;
132 }
133 }
134
135 /* set the current selection. Invoked by ioctl() or by kernel code. */
set_selection(const struct tiocl_selection __user * sel,struct tty_struct * tty)136 int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
137 {
138 struct vc_data *vc = vc_cons[fg_console].d;
139 int sel_mode, new_sel_start, new_sel_end, spc;
140 char *bp, *obp;
141 int i, ps, pe, multiplier;
142 u16 c;
143 struct kbd_struct *kbd = kbd_table + fg_console;
144
145 poke_blanked_console();
146
147 { unsigned short xs, ys, xe, ye;
148
149 if (!access_ok(VERIFY_READ, sel, sizeof(*sel)))
150 return -EFAULT;
151 __get_user(xs, &sel->xs);
152 __get_user(ys, &sel->ys);
153 __get_user(xe, &sel->xe);
154 __get_user(ye, &sel->ye);
155 __get_user(sel_mode, &sel->sel_mode);
156 xs--; ys--; xe--; ye--;
157 xs = limit(xs, vc->vc_cols - 1);
158 ys = limit(ys, vc->vc_rows - 1);
159 xe = limit(xe, vc->vc_cols - 1);
160 ye = limit(ye, vc->vc_rows - 1);
161 ps = ys * vc->vc_size_row + (xs << 1);
162 pe = ye * vc->vc_size_row + (xe << 1);
163
164 if (sel_mode == TIOCL_SELCLEAR) {
165 /* useful for screendump without selection highlights */
166 clear_selection();
167 return 0;
168 }
169
170 if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) {
171 mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys);
172 return 0;
173 }
174 }
175
176 if (ps > pe) /* make sel_start <= sel_end */
177 {
178 int tmp = ps;
179 ps = pe;
180 pe = tmp;
181 }
182
183 if (sel_cons != vc_cons[fg_console].d) {
184 clear_selection();
185 sel_cons = vc_cons[fg_console].d;
186 }
187 use_unicode = kbd && kbd->kbdmode == VC_UNICODE;
188
189 switch (sel_mode)
190 {
191 case TIOCL_SELCHAR: /* character-by-character selection */
192 new_sel_start = ps;
193 new_sel_end = pe;
194 break;
195 case TIOCL_SELWORD: /* word-by-word selection */
196 spc = isspace(sel_pos(ps));
197 for (new_sel_start = ps; ; ps -= 2)
198 {
199 if ((spc && !isspace(sel_pos(ps))) ||
200 (!spc && !inword(sel_pos(ps))))
201 break;
202 new_sel_start = ps;
203 if (!(ps % vc->vc_size_row))
204 break;
205 }
206 spc = isspace(sel_pos(pe));
207 for (new_sel_end = pe; ; pe += 2)
208 {
209 if ((spc && !isspace(sel_pos(pe))) ||
210 (!spc && !inword(sel_pos(pe))))
211 break;
212 new_sel_end = pe;
213 if (!((pe + 2) % vc->vc_size_row))
214 break;
215 }
216 break;
217 case TIOCL_SELLINE: /* line-by-line selection */
218 new_sel_start = ps - ps % vc->vc_size_row;
219 new_sel_end = pe + vc->vc_size_row
220 - pe % vc->vc_size_row - 2;
221 break;
222 case TIOCL_SELPOINTER:
223 highlight_pointer(pe);
224 return 0;
225 default:
226 return -EINVAL;
227 }
228
229 /* remove the pointer */
230 highlight_pointer(-1);
231
232 /* select to end of line if on trailing space */
233 if (new_sel_end > new_sel_start &&
234 !atedge(new_sel_end, vc->vc_size_row) &&
235 isspace(sel_pos(new_sel_end))) {
236 for (pe = new_sel_end + 2; ; pe += 2)
237 if (!isspace(sel_pos(pe)) ||
238 atedge(pe, vc->vc_size_row))
239 break;
240 if (isspace(sel_pos(pe)))
241 new_sel_end = pe;
242 }
243 if (sel_start == -1) /* no current selection */
244 highlight(new_sel_start, new_sel_end);
245 else if (new_sel_start == sel_start)
246 {
247 if (new_sel_end == sel_end) /* no action required */
248 return 0;
249 else if (new_sel_end > sel_end) /* extend to right */
250 highlight(sel_end + 2, new_sel_end);
251 else /* contract from right */
252 highlight(new_sel_end + 2, sel_end);
253 }
254 else if (new_sel_end == sel_end)
255 {
256 if (new_sel_start < sel_start) /* extend to left */
257 highlight(new_sel_start, sel_start - 2);
258 else /* contract from left */
259 highlight(sel_start, new_sel_start - 2);
260 }
261 else /* some other case; start selection from scratch */
262 {
263 clear_selection();
264 highlight(new_sel_start, new_sel_end);
265 }
266 sel_start = new_sel_start;
267 sel_end = new_sel_end;
268
269 /* Allocate a new buffer before freeing the old one ... */
270 multiplier = use_unicode ? 3 : 1; /* chars can take up to 3 bytes */
271 bp = kmalloc(((sel_end-sel_start)/2+1)*multiplier, GFP_KERNEL);
272 if (!bp) {
273 printk(KERN_WARNING "selection: kmalloc() failed\n");
274 clear_selection();
275 return -ENOMEM;
276 }
277 kfree(sel_buffer);
278 sel_buffer = bp;
279
280 obp = bp;
281 for (i = sel_start; i <= sel_end; i += 2) {
282 c = sel_pos(i);
283 if (use_unicode)
284 bp += store_utf8(c, bp);
285 else
286 *bp++ = c;
287 if (!isspace(c))
288 obp = bp;
289 if (! ((i + 2) % vc->vc_size_row)) {
290 /* strip trailing blanks from line and add newline,
291 unless non-space at end of line. */
292 if (obp != bp) {
293 bp = obp;
294 *bp++ = '\r';
295 }
296 obp = bp;
297 }
298 }
299 sel_buffer_lth = bp - sel_buffer;
300 return 0;
301 }
302
303 /* Insert the contents of the selection buffer into the
304 * queue of the tty associated with the current console.
305 * Invoked by ioctl().
306 */
paste_selection(struct tty_struct * tty)307 int paste_selection(struct tty_struct *tty)
308 {
309 struct vc_data *vc = tty->driver_data;
310 int pasted = 0;
311 unsigned int count;
312 struct tty_ldisc *ld;
313 DECLARE_WAITQUEUE(wait, current);
314
315 /* always called with BTM from vt_ioctl */
316 WARN_ON(!tty_locked());
317
318 console_lock();
319 poke_blanked_console();
320 console_unlock();
321
322 ld = tty_ldisc_ref(tty);
323 if (!ld) {
324 tty_unlock();
325 ld = tty_ldisc_ref_wait(tty);
326 tty_lock();
327 }
328
329 add_wait_queue(&vc->paste_wait, &wait);
330 while (sel_buffer && sel_buffer_lth > pasted) {
331 set_current_state(TASK_INTERRUPTIBLE);
332 if (test_bit(TTY_THROTTLED, &tty->flags)) {
333 schedule();
334 continue;
335 }
336 count = sel_buffer_lth - pasted;
337 count = min(count, tty->receive_room);
338 tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted,
339 NULL, count);
340 pasted += count;
341 }
342 remove_wait_queue(&vc->paste_wait, &wait);
343 __set_current_state(TASK_RUNNING);
344
345 tty_ldisc_deref(ld);
346 return 0;
347 }
348