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