summaryrefslogtreecommitdiffstats
path: root/drivers/char/selection.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/char/selection.c')
-rw-r--r--drivers/char/selection.c294
1 files changed, 294 insertions, 0 deletions
diff --git a/drivers/char/selection.c b/drivers/char/selection.c
new file mode 100644
index 000000000..552db4a61
--- /dev/null
+++ b/drivers/char/selection.c
@@ -0,0 +1,294 @@
+/*
+ * linux/drivers/char/selection.c
+ *
+ * This module exports the functions:
+ *
+ * 'int set_selection(const unsigned long arg)'
+ * 'void clear_selection(void)'
+ * 'int paste_selection(struct tty_struct *tty)'
+ * 'int sel_loadlut(const unsigned long arg)'
+ *
+ * Now that /dev/vcs exists, most of this can disappear again.
+ */
+
+#include <linux/tty.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/malloc.h>
+
+#include <asm/segment.h>
+
+#include "vt_kern.h"
+#include "consolemap.h"
+#include "selection.h"
+
+#ifndef MIN
+#define MIN(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+/* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
+#define isspace(c) ((c) == ' ')
+
+/* Variables for selection control. */
+/* Use a dynamic buffer, instead of static (Dec 1994) */
+ int sel_cons = 0; /* must not be disallocated */
+static volatile int sel_start = -1; /* cleared by clear_selection */
+static int sel_end;
+static int sel_buffer_lth = 0;
+static char *sel_buffer = NULL;
+
+#define sel_pos(n) inverse_translate(screen_word(sel_cons, n, 1) & 0xff)
+
+/* 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. */
+inline static void
+highlight(const int s, const int e) {
+ invert_screen(sel_cons, s, e-s+2, 1);
+}
+
+/* use complementary color to show the pointer */
+inline static void
+highlight_pointer(const int where) {
+ complement_pos(sel_cons, where);
+}
+
+/* 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 unsigned long 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(const unsigned long arg)
+{
+ int i = verify_area(VERIFY_READ, (char *) arg, 36);
+ if (i)
+ return i;
+ memcpy_fromfs(inwordLut, (unsigned long *)(arg+4), 32);
+ return 0;
+}
+
+/* does screen address p correspond to character at LH/RH edge of screen? */
+static inline int atedge(const int p)
+{
+ return (!(p % video_size_row) || !((p + 2) % video_size_row));
+}
+
+/* constrain v such that v <= u */
+static inline unsigned short limit(const unsigned short v, const unsigned short u)
+{
+/* gcc miscompiles the ?: operator, so don't use it.. */
+ if (v > u)
+ return u;
+ return v;
+}
+
+/* set the current selection. Invoked by ioctl(). */
+int set_selection(const unsigned long arg, struct tty_struct *tty)
+{
+ int sel_mode, new_sel_start, new_sel_end, spc;
+ char *bp, *obp;
+ int i, ps, pe;
+
+ do_unblank_screen();
+
+ { unsigned short *args, xs, ys, xe, ye;
+
+ args = (unsigned short *)(arg + 1);
+ xs = get_fs_word(args++) - 1;
+ ys = get_fs_word(args++) - 1;
+ xe = get_fs_word(args++) - 1;
+ ye = get_fs_word(args++) - 1;
+ sel_mode = get_fs_word(args);
+
+ xs = limit(xs, video_num_columns - 1);
+ ys = limit(ys, video_num_lines - 1);
+ xe = limit(xe, video_num_columns - 1);
+ ye = limit(ye, video_num_lines - 1);
+ ps = ys * video_size_row + (xs << 1);
+ pe = ye * video_size_row + (xe << 1);
+
+ if (sel_mode == 4) {
+ /* useful for screendump without selection highlights */
+ clear_selection();
+ return 0;
+ }
+
+ if (mouse_reporting() && (sel_mode & 16)) {
+ mouse_report(tty, sel_mode & 15, xs, ys);
+ return 0;
+ }
+ }
+
+ if (ps > pe) /* make sel_start <= sel_end */
+ {
+ int tmp = ps;
+ ps = pe;
+ pe = tmp;
+ }
+
+ if (sel_cons != fg_console) {
+ clear_selection();
+ sel_cons = fg_console;
+ }
+
+ switch (sel_mode)
+ {
+ case 0: /* character-by-character selection */
+ new_sel_start = ps;
+ new_sel_end = pe;
+ break;
+ case 1: /* 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 % video_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) % video_size_row))
+ break;
+ }
+ break;
+ case 2: /* line-by-line selection */
+ new_sel_start = ps - ps % video_size_row;
+ new_sel_end = pe + video_size_row
+ - pe % video_size_row - 2;
+ break;
+ case 3:
+ 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) && isspace(sel_pos(new_sel_end))) {
+ for (pe = new_sel_end + 2; ; pe += 2)
+ if (!isspace(sel_pos(pe)) || atedge(pe))
+ 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;
+
+ if (sel_buffer)
+ kfree(sel_buffer);
+ sel_buffer = kmalloc((sel_end-sel_start)/2+1, GFP_KERNEL);
+ if (!sel_buffer) {
+ printk("selection: kmalloc() failed\n");
+ clear_selection();
+ return -ENOMEM;
+ }
+
+ obp = bp = sel_buffer;
+ for (i = sel_start; i <= sel_end; i += 2) {
+ *bp = sel_pos(i);
+ if (!isspace(*bp++))
+ obp = bp;
+ if (! ((i + 2) % video_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 wait_queue wait = { current, NULL };
+ char *bp = sel_buffer;
+ int c = sel_buffer_lth;
+ int l;
+ struct vt_struct *vt = (struct vt_struct *) tty->driver_data;
+
+ if (!bp || !c)
+ return 0;
+ do_unblank_screen();
+ current->state = TASK_INTERRUPTIBLE;
+ add_wait_queue(&vt->paste_wait, &wait);
+ while (c) {
+ if (test_bit(TTY_THROTTLED, &tty->flags)) {
+ schedule();
+ continue;
+ }
+ l = MIN(c, tty->ldisc.receive_room(tty));
+ tty->ldisc.receive_buf(tty, bp, 0, l);
+ c -= l;
+ bp += l;
+ }
+ current->state = TASK_RUNNING;
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-20 05:48:02 +0000