| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * This module exports the functions: |
| * |
| * 'int set_selection_user(struct tiocl_selection __user *, |
| * struct tty_struct *)' |
| * 'int set_selection_kernel(struct tiocl_selection *, struct tty_struct *)' |
| * 'void clear_selection(void)' |
| * 'int paste_selection(struct tty_struct *)' |
| * 'int sel_loadlut(char __user *)' |
| * |
| * Now that /dev/vcs exists, most of this can disappear again. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/tty.h> |
| #include <linux/sched.h> |
| #include <linux/mm.h> |
| #include <linux/mutex.h> |
| #include <linux/slab.h> |
| #include <linux/types.h> |
| |
| #include <linux/uaccess.h> |
| |
| #include <linux/kbd_kern.h> |
| #include <linux/vt_kern.h> |
| #include <linux/consolemap.h> |
| #include <linux/selection.h> |
| #include <linux/tiocl.h> |
| #include <linux/console.h> |
| #include <linux/tty_flip.h> |
| |
| #include <linux/sched/signal.h> |
| |
| /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */ |
| #define is_space_on_vt(c) ((c) == ' ') |
| |
| /* FIXME: all this needs locking */ |
| static struct vc_selection { |
| struct mutex lock; |
| struct vc_data *cons; /* must not be deallocated */ |
| char *buffer; |
| unsigned int buf_len; |
| volatile int start; /* cleared by clear_selection */ |
| int end; |
| } vc_sel = { |
| .lock = __MUTEX_INITIALIZER(vc_sel.lock), |
| .start = -1, |
| }; |
| |
| /* clear_selection, highlight and highlight_pointer can be called |
| from interrupt (via scrollback/front) */ |
| |
| /* set reverse video on characters s-e of console with selection. */ |
| static inline void highlight(const int s, const int e) |
| { |
| invert_screen(vc_sel.cons, s, e-s+2, true); |
| } |
| |
| /* use complementary color to show the pointer */ |
| static inline void highlight_pointer(const int where) |
| { |
| complement_pos(vc_sel.cons, where); |
| } |
| |
| static u32 |
| sel_pos(int n, bool unicode) |
| { |
| if (unicode) |
| return screen_glyph_unicode(vc_sel.cons, n / 2); |
| return inverse_translate(vc_sel.cons, screen_glyph(vc_sel.cons, n), |
| false); |
| } |
| |
| /** |
| * clear_selection - remove current selection |
| * |
| * Remove the current selection highlight, if any from the console |
| * holding the selection. The caller must hold the console lock. |
| */ |
| void clear_selection(void) |
| { |
| highlight_pointer(-1); /* hide the pointer */ |
| if (vc_sel.start != -1) { |
| highlight(vc_sel.start, vc_sel.end); |
| vc_sel.start = -1; |
| } |
| } |
| EXPORT_SYMBOL_GPL(clear_selection); |
| |
| bool vc_is_sel(struct vc_data *vc) |
| { |
| return vc == vc_sel.cons; |
| } |
| |
| /* |
| * User settable table: what characters are to be considered alphabetic? |
| * 128 bits. Locked by the console lock. |
| */ |
| static u32 inwordLut[]={ |
| 0x00000000, /* control chars */ |
| 0x03FFE000, /* digits and "-./" */ |
| 0x87FFFFFE, /* uppercase and '_' */ |
| 0x07FFFFFE, /* lowercase */ |
| }; |
| |
| static inline int inword(const u32 c) |
| { |
| return c > 0x7f || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1); |
| } |
| |
| /** |
| * sel_loadlut() - load the LUT table |
| * @p: user table |
| * |
| * Load the LUT table from user space. The caller must hold the console |
| * lock. Make a temporary copy so a partial update doesn't make a mess. |
| */ |
| int sel_loadlut(char __user *p) |
| { |
| u32 tmplut[ARRAY_SIZE(inwordLut)]; |
| if (copy_from_user(tmplut, (u32 __user *)(p+4), sizeof(inwordLut))) |
| return -EFAULT; |
| memcpy(inwordLut, tmplut, sizeof(inwordLut)); |
| return 0; |
| } |
| |
| /* does screen address p correspond to character at LH/RH edge of screen? */ |
| static inline int atedge(const int p, int size_row) |
| { |
| return (!(p % size_row) || !((p + 2) % size_row)); |
| } |
| |
| /* stores the char in UTF8 and returns the number of bytes used (1-4) */ |
| static int store_utf8(u32 c, char *p) |
| { |
| if (c < 0x80) { |
| /* 0******* */ |
| p[0] = c; |
| return 1; |
| } else if (c < 0x800) { |
| /* 110***** 10****** */ |
| p[0] = 0xc0 | (c >> 6); |
| p[1] = 0x80 | (c & 0x3f); |
| return 2; |
| } else if (c < 0x10000) { |
| /* 1110**** 10****** 10****** */ |
| p[0] = 0xe0 | (c >> 12); |
| p[1] = 0x80 | ((c >> 6) & 0x3f); |
| p[2] = 0x80 | (c & 0x3f); |
| return 3; |
| } else if (c < 0x110000) { |
| /* 11110*** 10****** 10****** 10****** */ |
| p[0] = 0xf0 | (c >> 18); |
| p[1] = 0x80 | ((c >> 12) & 0x3f); |
| p[2] = 0x80 | ((c >> 6) & 0x3f); |
| p[3] = 0x80 | (c & 0x3f); |
| return 4; |
| } else { |
| /* outside Unicode, replace with U+FFFD */ |
| p[0] = 0xef; |
| p[1] = 0xbf; |
| p[2] = 0xbd; |
| return 3; |
| } |
| } |
| |
| /** |
| * set_selection_user - set the current selection. |
| * @sel: user selection info |
| * @tty: the console tty |
| * |
| * Invoked by the ioctl handle for the vt layer. |
| * |
| * The entire selection process is managed under the console_lock. It's |
| * a lot under the lock but its hardly a performance path |
| */ |
| int set_selection_user(const struct tiocl_selection __user *sel, |
| struct tty_struct *tty) |
| { |
| struct tiocl_selection v; |
| |
| if (copy_from_user(&v, sel, sizeof(*sel))) |
| return -EFAULT; |
| |
| return set_selection_kernel(&v, tty); |
| } |
| |
| static int vc_selection_store_chars(struct vc_data *vc, bool unicode) |
| { |
| char *bp, *obp; |
| unsigned int i; |
| |
| /* Allocate a new buffer before freeing the old one ... */ |
| /* chars can take up to 4 bytes with unicode */ |
| bp = kmalloc_array((vc_sel.end - vc_sel.start) / 2 + 1, unicode ? 4 : 1, |
| GFP_KERNEL | __GFP_NOWARN); |
| if (!bp) { |
| printk(KERN_WARNING "selection: kmalloc() failed\n"); |
| clear_selection(); |
| return -ENOMEM; |
| } |
| kfree(vc_sel.buffer); |
| vc_sel.buffer = bp; |
| |
| obp = bp; |
| for (i = vc_sel.start; i <= vc_sel.end; i += 2) { |
| u32 c = sel_pos(i, unicode); |
| if (unicode) |
| bp += store_utf8(c, bp); |
| else |
| *bp++ = c; |
| if (!is_space_on_vt(c)) |
| obp = bp; |
| if (!((i + 2) % vc->vc_size_row)) { |
| /* strip trailing blanks from line and add newline, |
| unless non-space at end of line. */ |
| if (obp != bp) { |
| bp = obp; |
| *bp++ = '\r'; |
| } |
| obp = bp; |
| } |
| } |
| vc_sel.buf_len = bp - vc_sel.buffer; |
| |
| return 0; |
| } |
| |
| static int vc_do_selection(struct vc_data *vc, unsigned short mode, int ps, |
| int pe) |
| { |
| int new_sel_start, new_sel_end, spc; |
| bool unicode = vt_do_kdgkbmode(fg_console) == K_UNICODE; |
| |
| switch (mode) { |
| case TIOCL_SELCHAR: /* character-by-character selection */ |
| new_sel_start = ps; |
| new_sel_end = pe; |
| break; |
| case TIOCL_SELWORD: /* word-by-word selection */ |
| spc = is_space_on_vt(sel_pos(ps, unicode)); |
| for (new_sel_start = ps; ; ps -= 2) { |
| if ((spc && !is_space_on_vt(sel_pos(ps, unicode))) || |
| (!spc && !inword(sel_pos(ps, unicode)))) |
| break; |
| new_sel_start = ps; |
| if (!(ps % vc->vc_size_row)) |
| break; |
| } |
| |
| spc = is_space_on_vt(sel_pos(pe, unicode)); |
| for (new_sel_end = pe; ; pe += 2) { |
| if ((spc && !is_space_on_vt(sel_pos(pe, unicode))) || |
| (!spc && !inword(sel_pos(pe, unicode)))) |
| break; |
| new_sel_end = pe; |
| if (!((pe + 2) % vc->vc_size_row)) |
| break; |
| } |
| break; |
| case TIOCL_SELLINE: /* line-by-line selection */ |
| new_sel_start = rounddown(ps, vc->vc_size_row); |
| new_sel_end = rounddown(pe, vc->vc_size_row) + |
| vc->vc_size_row - 2; |
| break; |
| case TIOCL_SELPOINTER: |
| highlight_pointer(pe); |
| return 0; |
| default: |
| return -EINVAL; |
| } |
| |
| /* remove the pointer */ |
| highlight_pointer(-1); |
| |
| /* select to end of line if on trailing space */ |
| if (new_sel_end > new_sel_start && |
| !atedge(new_sel_end, vc->vc_size_row) && |
| is_space_on_vt(sel_pos(new_sel_end, unicode))) { |
| for (pe = new_sel_end + 2; ; pe += 2) |
| if (!is_space_on_vt(sel_pos(pe, unicode)) || |
| atedge(pe, vc->vc_size_row)) |
| break; |
| if (is_space_on_vt(sel_pos(pe, unicode))) |
| new_sel_end = pe; |
| } |
| if (vc_sel.start == -1) /* no current selection */ |
| highlight(new_sel_start, new_sel_end); |
| else if (new_sel_start == vc_sel.start) |
| { |
| if (new_sel_end == vc_sel.end) /* no action required */ |
| return 0; |
| else if (new_sel_end > vc_sel.end) /* extend to right */ |
| highlight(vc_sel.end + 2, new_sel_end); |
| else /* contract from right */ |
| highlight(new_sel_end + 2, vc_sel.end); |
| } |
| else if (new_sel_end == vc_sel.end) |
| { |
| if (new_sel_start < vc_sel.start) /* extend to left */ |
| highlight(new_sel_start, vc_sel.start - 2); |
| else /* contract from left */ |
| highlight(vc_sel.start, new_sel_start - 2); |
| } |
| else /* some other case; start selection from scratch */ |
| { |
| clear_selection(); |
| highlight(new_sel_start, new_sel_end); |
| } |
| vc_sel.start = new_sel_start; |
| vc_sel.end = new_sel_end; |
| |
| return vc_selection_store_chars(vc, unicode); |
| } |
| |
| static int vc_selection(struct vc_data *vc, struct tiocl_selection *v, |
| struct tty_struct *tty) |
| { |
| int ps, pe; |
| |
| poke_blanked_console(); |
| |
| if (v->sel_mode == TIOCL_SELCLEAR) { |
| /* useful for screendump without selection highlights */ |
| clear_selection(); |
| return 0; |
| } |
| |
| v->xs = min_t(u16, v->xs - 1, vc->vc_cols - 1); |
| v->ys = min_t(u16, v->ys - 1, vc->vc_rows - 1); |
| v->xe = min_t(u16, v->xe - 1, vc->vc_cols - 1); |
| v->ye = min_t(u16, v->ye - 1, vc->vc_rows - 1); |
| |
| if (mouse_reporting() && (v->sel_mode & TIOCL_SELMOUSEREPORT)) { |
| mouse_report(tty, v->sel_mode & TIOCL_SELBUTTONMASK, v->xs, |
| v->ys); |
| return 0; |
| } |
| |
| ps = v->ys * vc->vc_size_row + (v->xs << 1); |
| pe = v->ye * vc->vc_size_row + (v->xe << 1); |
| if (ps > pe) /* make vc_sel.start <= vc_sel.end */ |
| swap(ps, pe); |
| |
| if (vc_sel.cons != vc) { |
| clear_selection(); |
| vc_sel.cons = vc; |
| } |
| |
| return vc_do_selection(vc, v->sel_mode, ps, pe); |
| } |
| |
| int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty) |
| { |
| int ret; |
| |
| mutex_lock(&vc_sel.lock); |
| console_lock(); |
| ret = vc_selection(vc_cons[fg_console].d, v, tty); |
| console_unlock(); |
| mutex_unlock(&vc_sel.lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(set_selection_kernel); |
| |
| /* Insert the contents of the selection buffer into the |
| * queue of the tty associated with the current console. |
| * Invoked by ioctl(). |
| * |
| * Locking: called without locks. Calls the ldisc wrongly with |
| * unsafe methods, |
| */ |
| int paste_selection(struct tty_struct *tty) |
| { |
| struct vc_data *vc = tty->driver_data; |
| int pasted = 0; |
| unsigned int count; |
| struct tty_ldisc *ld; |
| DECLARE_WAITQUEUE(wait, current); |
| int ret = 0; |
| |
| console_lock(); |
| poke_blanked_console(); |
| console_unlock(); |
| |
| ld = tty_ldisc_ref_wait(tty); |
| if (!ld) |
| return -EIO; /* ldisc was hung up */ |
| tty_buffer_lock_exclusive(&vc->port); |
| |
| add_wait_queue(&vc->paste_wait, &wait); |
| mutex_lock(&vc_sel.lock); |
| while (vc_sel.buffer && vc_sel.buf_len > pasted) { |
| set_current_state(TASK_INTERRUPTIBLE); |
| if (signal_pending(current)) { |
| ret = -EINTR; |
| break; |
| } |
| if (tty_throttled(tty)) { |
| mutex_unlock(&vc_sel.lock); |
| schedule(); |
| mutex_lock(&vc_sel.lock); |
| continue; |
| } |
| __set_current_state(TASK_RUNNING); |
| count = vc_sel.buf_len - pasted; |
| count = tty_ldisc_receive_buf(ld, vc_sel.buffer + pasted, NULL, |
| count); |
| pasted += count; |
| } |
| mutex_unlock(&vc_sel.lock); |
| remove_wait_queue(&vc->paste_wait, &wait); |
| __set_current_state(TASK_RUNNING); |
| |
| tty_buffer_unlock_exclusive(&vc->port); |
| tty_ldisc_deref(ld); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(paste_selection); |