// 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* Don't take this from : 011-015 on the screen aren't spaces */ #define isspace(c) ((c) == ' ') extern void poke_blanked_console(void); /* FIXME: all this needs locking */ /* Variables for selection control. */ /* Use a dynamic buffer, instead of static (Dec 1994) */ struct vc_data *sel_cons; /* must not be deallocated */ static int use_unicode; static volatile int sel_start = -1; /* cleared by clear_selection */ static int sel_end; static int sel_buffer_lth; static char *sel_buffer; static DEFINE_MUTEX(sel_lock); /* 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(sel_cons, s, e-s+2, 1); } /* use complementary color to show the pointer */ static inline void highlight_pointer(const int where) { complement_pos(sel_cons, where); } static u32 sel_pos(int n) { if (use_unicode) return screen_glyph_unicode(sel_cons, n / 2); return inverse_translate(sel_cons, screen_glyph(sel_cons, n), 0); } /** * 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 (sel_start != -1) { highlight(sel_start, sel_end); sel_start = -1; } } EXPORT_SYMBOL_GPL(clear_selection); bool vc_is_sel(struct vc_data *vc) { return 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); } /** * set 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); } int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty) { struct vc_data *vc = vc_cons[fg_console].d; int new_sel_start, new_sel_end, spc; char *bp, *obp; int i, ps, pe, multiplier; u32 c; int mode, ret = 0; poke_blanked_console(); 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); ps = v->ys * vc->vc_size_row + (v->xs << 1); pe = v->ye * vc->vc_size_row + (v->xe << 1); if (v->sel_mode == TIOCL_SELCLEAR) { /* useful for screendump without selection highlights */ clear_selection(); return 0; } if (mouse_reporting() && (v->sel_mode & TIOCL_SELMOUSEREPORT)) { mouse_report(tty, v->sel_mode & TIOCL_SELBUTTONMASK, v->xs, v->ys); return 0; } if (ps > pe) /* make sel_start <= sel_end */ swap(ps, pe); mutex_lock(&sel_lock); if (sel_cons != vc_cons[fg_console].d) { clear_selection(); sel_cons = vc_cons[fg_console].d; } mode = vt_do_kdgkbmode(fg_console); if (mode == K_UNICODE) use_unicode = 1; else use_unicode = 0; switch (v->sel_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 = isspace(sel_pos(ps)); for (new_sel_start = ps; ; ps -= 2) { if ((spc && !isspace(sel_pos(ps))) || (!spc && !inword(sel_pos(ps)))) break; new_sel_start = ps; if (!(ps % vc->vc_size_row)) break; } spc = isspace(sel_pos(pe)); for (new_sel_end = pe; ; pe += 2) { if ((spc && !isspace(sel_pos(pe))) || (!spc && !inword(sel_pos(pe)))) break; new_sel_end = pe; if (!((pe + 2) % vc->vc_size_row)) break; } break; case TIOCL_SELLINE: /* line-by-line selection */ new_sel_start = ps - ps % vc->vc_size_row; new_sel_end = pe + vc->vc_size_row - pe % vc->vc_size_row - 2; break; case TIOCL_SELPOINTER: highlight_pointer(pe); goto unlock; default: ret = -EINVAL; goto unlock; } /* 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) && isspace(sel_pos(new_sel_end))) { for (pe = new_sel_end + 2; ; pe += 2) if (!isspace(sel_pos(pe)) || atedge(pe, vc->vc_size_row)) break; if (isspace(sel_pos(pe))) new_sel_end = pe; } if (sel_start == -1) /* no current selection */ highlight(new_sel_start, new_sel_end); else if (new_sel_start == sel_start) { if (new_sel_end == sel_end) /* no action required */ goto unlock; else if (new_sel_end > sel_end) /* extend to right */ highlight(sel_end + 2, new_sel_end); else /* contract from right */ highlight(new_sel_end + 2, sel_end); } else if (new_sel_end == sel_end) { if (new_sel_start < sel_start) /* extend to left */ highlight(new_sel_start, sel_start - 2); else /* contract from left */ highlight(sel_start, new_sel_start - 2); } else /* some other case; start selection from scratch */ { clear_selection(); highlight(new_sel_start, new_sel_end); } sel_start = new_sel_start; sel_end = new_sel_end; /* Allocate a new buffer before freeing the old one ... */ multiplier = use_unicode ? 4 : 1; /* chars can take up to 4 bytes */ bp = kmalloc_array((sel_end - sel_start) / 2 + 1, multiplier, GFP_KERNEL); if (!bp) { printk(KERN_WARNING "selection: kmalloc() failed\n"); clear_selection(); ret = -ENOMEM; goto unlock; } kfree(sel_buffer); sel_buffer = bp; obp = bp; for (i = sel_start; i <= sel_end; i += 2) { c = sel_pos(i); if (use_unicode) bp += store_utf8(c, bp); else *bp++ = c; if (!isspace(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; } } sel_buffer_lth = bp - sel_buffer; unlock: mutex_unlock(&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(&sel_lock); while (sel_buffer && sel_buffer_lth > pasted) { set_current_state(TASK_INTERRUPTIBLE); if (signal_pending(current)) { ret = -EINTR; break; } if (tty_throttled(tty)) { mutex_unlock(&sel_lock); schedule(); mutex_lock(&sel_lock); continue; } __set_current_state(TASK_RUNNING); count = sel_buffer_lth - pasted; count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL, count); pasted += count; } mutex_unlock(&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);