diff options
Diffstat (limited to 'drivers/char/selection.c')
| -rw-r--r-- | drivers/char/selection.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/char/selection.c b/drivers/char/selection.c new file mode 100644 index 000000000000..16d630f58bb4 --- /dev/null +++ b/drivers/char/selection.c @@ -0,0 +1,306 @@ +/* + * linux/drivers/char/selection.c + * + * This module exports the functions: + * + * 'int set_selection(struct tiocl_selection __user *, 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/slab.h> +#include <linux/types.h> + +#include <asm/uaccess.h> + +#include <linux/vt_kern.h> +#include <linux/consolemap.h> +#include <linux/selection.h> +#include <linux/tiocl.h> +#include <linux/console.h> + +/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */ +#define isspace(c) ((c) == ' ') + +extern void poke_blanked_console(void); + +/* Variables for selection control. */ +/* Use a dynamic buffer, instead of static (Dec 1994) */ +struct vc_data *sel_cons; /* must not be disallocated */ +static volatile int sel_start = -1; /* cleared by clear_selection */ +static int sel_end; +static int sel_buffer_lth; +static char *sel_buffer; + +/* 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 unsigned char +sel_pos(int n) +{ + return inverse_translate(sel_cons, screen_glyph(sel_cons, n)); +} + +/* remove the current selection highlight, if any, + from the console holding the selection. */ +void +clear_selection(void) { + highlight_pointer(-1); /* hide the pointer */ + if (sel_start != -1) { + highlight(sel_start, sel_end); + sel_start = -1; + } +} + +/* + * User settable table: what characters are to be considered alphabetic? + * 256 bits + */ +static u32 inwordLut[8]={ + 0x00000000, /* control chars */ + 0x03FF0000, /* digits */ + 0x87FFFFFE, /* uppercase and '_' */ + 0x07FFFFFE, /* lowercase */ + 0x00000000, + 0x00000000, + 0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */ + 0xFF7FFFFF /* latin-1 accented letters, not division sign */ +}; + +static inline int inword(const unsigned char c) { + return ( inwordLut[c>>5] >> (c & 0x1F) ) & 1; +} + +/* set inwordLut contents. Invoked by ioctl(). */ +int sel_loadlut(char __user *p) +{ + return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 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)); +} + +/* constrain v such that v <= u */ +static inline unsigned short limit(const unsigned short v, const unsigned short u) +{ + return (v > u) ? u : v; +} + +/* set the current selection. Invoked by ioctl() or by kernel code. */ +int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty) +{ + struct vc_data *vc = vc_cons[fg_console].d; + int sel_mode, new_sel_start, new_sel_end, spc; + char *bp, *obp; + int i, ps, pe; + + poke_blanked_console(); + + { unsigned short xs, ys, xe, ye; + + if (!access_ok(VERIFY_READ, sel, sizeof(*sel))) + return -EFAULT; + __get_user(xs, &sel->xs); + __get_user(ys, &sel->ys); + __get_user(xe, &sel->xe); + __get_user(ye, &sel->ye); + __get_user(sel_mode, &sel->sel_mode); + xs--; ys--; xe--; ye--; + xs = limit(xs, vc->vc_cols - 1); + ys = limit(ys, vc->vc_rows - 1); + xe = limit(xe, vc->vc_cols - 1); + ye = limit(ye, vc->vc_rows - 1); + ps = ys * vc->vc_size_row + (xs << 1); + pe = ye * vc->vc_size_row + (xe << 1); + + if (sel_mode == TIOCL_SELCLEAR) { + /* useful for screendump without selection highlights */ + clear_selection(); + return 0; + } + + if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) { + mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys); + return 0; + } + } + + if (ps > pe) /* make sel_start <= sel_end */ + { + int tmp = ps; + ps = pe; + pe = tmp; + } + + if (sel_cons != vc_cons[fg_console].d) { + clear_selection(); + sel_cons = vc_cons[fg_console].d; + } + + switch (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); + 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) && + 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 */ + return 0; + 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 ... */ + bp = kmalloc((sel_end-sel_start)/2+1, GFP_KERNEL); + if (!bp) { + printk(KERN_WARNING "selection: kmalloc() failed\n"); + clear_selection(); + return -ENOMEM; + } + if (sel_buffer) + kfree(sel_buffer); + sel_buffer = bp; + + obp = bp; + for (i = sel_start; i <= sel_end; i += 2) { + *bp = sel_pos(i); + if (!isspace(*bp++)) + 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; + return 0; +} + +/* Insert the contents of the selection buffer into the + * queue of the tty associated with the current console. + * Invoked by ioctl(). + */ +int paste_selection(struct tty_struct *tty) +{ + struct vc_data *vc = (struct vc_data *)tty->driver_data; + int pasted = 0, count; + struct tty_ldisc *ld; + DECLARE_WAITQUEUE(wait, current); + + acquire_console_sem(); + poke_blanked_console(); + release_console_sem(); + + ld = tty_ldisc_ref_wait(tty); + + add_wait_queue(&vc->paste_wait, &wait); + while (sel_buffer && sel_buffer_lth > pasted) { + set_current_state(TASK_INTERRUPTIBLE); + if (test_bit(TTY_THROTTLED, &tty->flags)) { + schedule(); + continue; + } + count = sel_buffer_lth - pasted; + count = min(count, tty->ldisc.receive_room(tty)); + tty->ldisc.receive_buf(tty, sel_buffer + pasted, NULL, count); + pasted += count; + } + remove_wait_queue(&vc->paste_wait, &wait); + current->state = TASK_RUNNING; + + tty_ldisc_deref(ld); + return 0; +} |