1 /*
2 * This module exports the functions:
3 *
4 * 'int set_selection(struct tiocl_selection __user *, struct tty_struct *)'
5 * 'void clear_selection(void)'
6 * 'int paste_selection(struct tty_struct *)'
7 * 'int sel_loadlut(char __user *)'
8 *
9 * Now that /dev/vcs exists, most of this can disappear again.
10 */
11
12 #include <linux/module.h>
13 #include <linux/tty.h>
14 #include <linux/sched.h>
15 #include <linux/mm.h>
16 #include <linux/slab.h>
17 #include <linux/types.h>
18
19 #include <asm/uaccess.h>
20
21 #include <linux/kbd_kern.h>
22 #include <linux/vt_kern.h>
23 #include <linux/consolemap.h>
24 #include <linux/selection.h>
25 #include <linux/tiocl.h>
26 #include <linux/console.h>
27
28 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
29 #define isspace(c) ((c) == ' ')
30
31 extern void poke_blanked_console(void);
32
33 /* FIXME: all this needs locking */
34 /* Variables for selection control. */
35 /* Use a dynamic buffer, instead of static (Dec 1994) */
36 struct vc_data *sel_cons; /* must not be deallocated */
37 static int use_unicode;
38 static volatile int sel_start = -1; /* cleared by clear_selection */
39 static int sel_end;
40 static int sel_buffer_lth;
41 static char *sel_buffer;
42
43 /* clear_selection, highlight and highlight_pointer can be called
44 from interrupt (via scrollback/front) */
45
46 /* set reverse video on characters s-e of console with selection. */
highlight(const int s,const int e)47 static inline void highlight(const int s, const int e)
48 {
49 invert_screen(sel_cons, s, e-s+2, 1);
50 }
51
52 /* use complementary color to show the pointer */
highlight_pointer(const int where)53 static inline void highlight_pointer(const int where)
54 {
55 complement_pos(sel_cons, where);
56 }
57
58 static u16
sel_pos(int n)59 sel_pos(int n)
60 {
61 return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
62 use_unicode);
63 }
64
65 /**
66 * clear_selection - remove current selection
67 *
68 * Remove the current selection highlight, if any from the console
69 * holding the selection. The caller must hold the console lock.
70 */
clear_selection(void)71 void clear_selection(void)
72 {
73 highlight_pointer(-1); /* hide the pointer */
74 if (sel_start != -1) {
75 highlight(sel_start, sel_end);
76 sel_start = -1;
77 }
78 }
79
80 /*
81 * User settable table: what characters are to be considered alphabetic?
82 * 256 bits. Locked by the console lock.
83 */
84 static u32 inwordLut[8]={
85 0x00000000, /* control chars */
86 0x03FF0000, /* digits */
87 0x87FFFFFE, /* uppercase and '_' */
88 0x07FFFFFE, /* lowercase */
89 0x00000000,
90 0x00000000,
91 0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
92 0xFF7FFFFF /* latin-1 accented letters, not division sign */
93 };
94
inword(const u16 c)95 static inline int inword(const u16 c) {
96 return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
97 }
98
99 /**
100 * set loadlut - load the LUT table
101 * @p: user table
102 *
103 * Load the LUT table from user space. The caller must hold the console
104 * lock. Make a temporary copy so a partial update doesn't make a mess.
105 */
sel_loadlut(char __user * p)106 int sel_loadlut(char __user *p)
107 {
108 u32 tmplut[8];
109 if (copy_from_user(tmplut, (u32 __user *)(p+4), 32))
110 return -EFAULT;
111 memcpy(inwordLut, tmplut, 32);
112 return 0;
113 }
114
115 /* does screen address p correspond to character at LH/RH edge of screen? */
atedge(const int p,int size_row)116 static inline int atedge(const int p, int size_row)
117 {
118 return (!(p % size_row) || !((p + 2) % size_row));
119 }
120
121 /* constrain v such that v <= u */
limit(const unsigned short v,const unsigned short u)122 static inline unsigned short limit(const unsigned short v, const unsigned short u)
123 {
124 return (v > u) ? u : v;
125 }
126
127 /* stores the char in UTF8 and returns the number of bytes used (1-3) */
store_utf8(u16 c,char * p)128 static int store_utf8(u16 c, char *p)
129 {
130 if (c < 0x80) {
131 /* 0******* */
132 p[0] = c;
133 return 1;
134 } else if (c < 0x800) {
135 /* 110***** 10****** */
136 p[0] = 0xc0 | (c >> 6);
137 p[1] = 0x80 | (c & 0x3f);
138 return 2;
139 } else {
140 /* 1110**** 10****** 10****** */
141 p[0] = 0xe0 | (c >> 12);
142 p[1] = 0x80 | ((c >> 6) & 0x3f);
143 p[2] = 0x80 | (c & 0x3f);
144 return 3;
145 }
146 }
147
148 /**
149 * set_selection - set the current selection.
150 * @sel: user selection info
151 * @tty: the console tty
152 *
153 * Invoked by the ioctl handle for the vt layer.
154 *
155 * The entire selection process is managed under the console_lock. It's
156 * a lot under the lock but its hardly a performance path
157 */
set_selection(const struct tiocl_selection __user * sel,struct tty_struct * tty)158 int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
159 {
160 struct vc_data *vc = vc_cons[fg_console].d;
161 int sel_mode, new_sel_start, new_sel_end, spc;
162 char *bp, *obp;
163 int i, ps, pe, multiplier;
164 u16 c;
165 int mode;
166
167 poke_blanked_console();
168
169 { unsigned short xs, ys, xe, ye;
170
171 if (!access_ok(VERIFY_READ, sel, sizeof(*sel)))
172 return -EFAULT;
173 __get_user(xs, &sel->xs);
174 __get_user(ys, &sel->ys);
175 __get_user(xe, &sel->xe);
176 __get_user(ye, &sel->ye);
177 __get_user(sel_mode, &sel->sel_mode);
178 xs--; ys--; xe--; ye--;
179 xs = limit(xs, vc->vc_cols - 1);
180 ys = limit(ys, vc->vc_rows - 1);
181 xe = limit(xe, vc->vc_cols - 1);
182 ye = limit(ye, vc->vc_rows - 1);
183 ps = ys * vc->vc_size_row + (xs << 1);
184 pe = ye * vc->vc_size_row + (xe << 1);
185
186 if (sel_mode == TIOCL_SELCLEAR) {
187 /* useful for screendump without selection highlights */
188 clear_selection();
189 return 0;
190 }
191
192 if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) {
193 mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys);
194 return 0;
195 }
196 }
197
198 if (ps > pe) /* make sel_start <= sel_end */
199 {
200 int tmp = ps;
201 ps = pe;
202 pe = tmp;
203 }
204
205 if (sel_cons != vc_cons[fg_console].d) {
206 clear_selection();
207 sel_cons = vc_cons[fg_console].d;
208 }
209 mode = vt_do_kdgkbmode(fg_console);
210 if (mode == K_UNICODE)
211 use_unicode = 1;
212 else
213 use_unicode = 0;
214
215 switch (sel_mode)
216 {
217 case TIOCL_SELCHAR: /* character-by-character selection */
218 new_sel_start = ps;
219 new_sel_end = pe;
220 break;
221 case TIOCL_SELWORD: /* word-by-word selection */
222 spc = isspace(sel_pos(ps));
223 for (new_sel_start = ps; ; ps -= 2)
224 {
225 if ((spc && !isspace(sel_pos(ps))) ||
226 (!spc && !inword(sel_pos(ps))))
227 break;
228 new_sel_start = ps;
229 if (!(ps % vc->vc_size_row))
230 break;
231 }
232 spc = isspace(sel_pos(pe));
233 for (new_sel_end = pe; ; pe += 2)
234 {
235 if ((spc && !isspace(sel_pos(pe))) ||
236 (!spc && !inword(sel_pos(pe))))
237 break;
238 new_sel_end = pe;
239 if (!((pe + 2) % vc->vc_size_row))
240 break;
241 }
242 break;
243 case TIOCL_SELLINE: /* line-by-line selection */
244 new_sel_start = ps - ps % vc->vc_size_row;
245 new_sel_end = pe + vc->vc_size_row
246 - pe % vc->vc_size_row - 2;
247 break;
248 case TIOCL_SELPOINTER:
249 highlight_pointer(pe);
250 return 0;
251 default:
252 return -EINVAL;
253 }
254
255 /* remove the pointer */
256 highlight_pointer(-1);
257
258 /* select to end of line if on trailing space */
259 if (new_sel_end > new_sel_start &&
260 !atedge(new_sel_end, vc->vc_size_row) &&
261 isspace(sel_pos(new_sel_end))) {
262 for (pe = new_sel_end + 2; ; pe += 2)
263 if (!isspace(sel_pos(pe)) ||
264 atedge(pe, vc->vc_size_row))
265 break;
266 if (isspace(sel_pos(pe)))
267 new_sel_end = pe;
268 }
269 if (sel_start == -1) /* no current selection */
270 highlight(new_sel_start, new_sel_end);
271 else if (new_sel_start == sel_start)
272 {
273 if (new_sel_end == sel_end) /* no action required */
274 return 0;
275 else if (new_sel_end > sel_end) /* extend to right */
276 highlight(sel_end + 2, new_sel_end);
277 else /* contract from right */
278 highlight(new_sel_end + 2, sel_end);
279 }
280 else if (new_sel_end == sel_end)
281 {
282 if (new_sel_start < sel_start) /* extend to left */
283 highlight(new_sel_start, sel_start - 2);
284 else /* contract from left */
285 highlight(sel_start, new_sel_start - 2);
286 }
287 else /* some other case; start selection from scratch */
288 {
289 clear_selection();
290 highlight(new_sel_start, new_sel_end);
291 }
292 sel_start = new_sel_start;
293 sel_end = new_sel_end;
294
295 /* Allocate a new buffer before freeing the old one ... */
296 multiplier = use_unicode ? 3 : 1; /* chars can take up to 3 bytes */
297 bp = kmalloc(((sel_end-sel_start)/2+1)*multiplier, GFP_KERNEL);
298 if (!bp) {
299 printk(KERN_WARNING "selection: kmalloc() failed\n");
300 clear_selection();
301 return -ENOMEM;
302 }
303 kfree(sel_buffer);
304 sel_buffer = bp;
305
306 obp = bp;
307 for (i = sel_start; i <= sel_end; i += 2) {
308 c = sel_pos(i);
309 if (use_unicode)
310 bp += store_utf8(c, bp);
311 else
312 *bp++ = c;
313 if (!isspace(c))
314 obp = bp;
315 if (! ((i + 2) % vc->vc_size_row)) {
316 /* strip trailing blanks from line and add newline,
317 unless non-space at end of line. */
318 if (obp != bp) {
319 bp = obp;
320 *bp++ = '\r';
321 }
322 obp = bp;
323 }
324 }
325 sel_buffer_lth = bp - sel_buffer;
326 return 0;
327 }
328
329 /* Insert the contents of the selection buffer into the
330 * queue of the tty associated with the current console.
331 * Invoked by ioctl().
332 *
333 * Locking: called without locks. Calls the ldisc wrongly with
334 * unsafe methods,
335 */
paste_selection(struct tty_struct * tty)336 int paste_selection(struct tty_struct *tty)
337 {
338 struct vc_data *vc = tty->driver_data;
339 int pasted = 0;
340 unsigned int count;
341 struct tty_ldisc *ld;
342 DECLARE_WAITQUEUE(wait, current);
343
344
345 console_lock();
346 poke_blanked_console();
347 console_unlock();
348
349 /* FIXME: wtf is this supposed to achieve ? */
350 ld = tty_ldisc_ref(tty);
351 if (!ld)
352 ld = tty_ldisc_ref_wait(tty);
353
354 /* FIXME: this is completely unsafe */
355 add_wait_queue(&vc->paste_wait, &wait);
356 while (sel_buffer && sel_buffer_lth > pasted) {
357 set_current_state(TASK_INTERRUPTIBLE);
358 if (test_bit(TTY_THROTTLED, &tty->flags)) {
359 schedule();
360 continue;
361 }
362 count = sel_buffer_lth - pasted;
363 count = min(count, tty->receive_room);
364 tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted,
365 NULL, count);
366 pasted += count;
367 }
368 remove_wait_queue(&vc->paste_wait, &wait);
369 __set_current_state(TASK_RUNNING);
370
371 tty_ldisc_deref(ld);
372 return 0;
373 }
374