patch 8.2.0443: clipboard code is spread outv8.2.0443

Problem:    Clipboard code is spread out.
Solution:   Move clipboard code to its own file. (Yegappan Lakshmanan,
            closes #5827)

1 files changed, 2212 insertions, 0 deletions

diff --git a/src/clipboard.c b/src/clipboard.c
new file mode 100644
index 0000000000..e9e426f52d
--- /dev/null
+++ b/src/clipboard.c
@@ -0,0 +1,2212 @@
+/* vi:set ts=8 sts=4 sw=4 noet:
+ *
+ * VIM - Vi IMproved	by Bram Moolenaar
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+
+/*
+ * clipboard.c: Functions to handle the clipboard
+ */
+
+#include "vim.h"
+
+#ifdef FEAT_CYGWIN_WIN32_CLIPBOARD
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+# include "winclip.pro"
+#endif
+
+// Functions for copying and pasting text between applications.
+// This is always included in a GUI version, but may also be included when the
+// clipboard and mouse is available to a terminal version such as xterm.
+// Note: there are some more functions in ops.c that handle selection stuff.
+//
+// Also note that the majority of functions here deal with the X 'primary'
+// (visible - for Visual mode use) selection, and only that. There are no
+// versions of these for the 'clipboard' selection, as Visual mode has no use
+// for them.
+
+#if defined(FEAT_CLIPBOARD) || defined(PROTO)
+
+/*
+ * Selection stuff using Visual mode, for cutting and pasting text to other
+ * windows.
+ */
+
+/*
+ * Call this to initialise the clipboard.  Pass it FALSE if the clipboard code
+ * is included, but the clipboard can not be used, or TRUE if the clipboard can
+ * be used.  Eg unix may call this with FALSE, then call it again with TRUE if
+ * the GUI starts.
+ */
+    void
+clip_init(int can_use)
+{
+    Clipboard_T *cb;
+
+    cb = &clip_star;
+    for (;;)
+    {
+	cb->available  = can_use;
+	cb->owned      = FALSE;
+	cb->start.lnum = 0;
+	cb->start.col  = 0;
+	cb->end.lnum   = 0;
+	cb->end.col    = 0;
+	cb->state      = SELECT_CLEARED;
+
+	if (cb == &clip_plus)
+	    break;
+	cb = &clip_plus;
+    }
+}
+
+/*
+ * Check whether the VIsual area has changed, and if so try to become the owner
+ * of the selection, and free any old converted selection we may still have
+ * lying around.  If the VIsual mode has ended, make a copy of what was
+ * selected so we can still give it to others.	Will probably have to make sure
+ * this is called whenever VIsual mode is ended.
+ */
+    void
+clip_update_selection(Clipboard_T *clip)
+{
+    pos_T	    start, end;
+
+    // If visual mode is only due to a redo command ("."), then ignore it
+    if (!redo_VIsual_busy && VIsual_active && (State & NORMAL))
+    {
+	if (LT_POS(VIsual, curwin->w_cursor))
+	{
+	    start = VIsual;
+	    end = curwin->w_cursor;
+	    if (has_mbyte)
+		end.col += (*mb_ptr2len)(ml_get_cursor()) - 1;
+	}
+	else
+	{
+	    start = curwin->w_cursor;
+	    end = VIsual;
+	}
+	if (!EQUAL_POS(clip->start, start)
+		|| !EQUAL_POS(clip->end, end)
+		|| clip->vmode != VIsual_mode)
+	{
+	    clip_clear_selection(clip);
+	    clip->start = start;
+	    clip->end = end;
+	    clip->vmode = VIsual_mode;
+	    clip_free_selection(clip);
+	    clip_own_selection(clip);
+	    clip_gen_set_selection(clip);
+	}
+    }
+}
+
+    static int
+clip_gen_own_selection(Clipboard_T *cbd)
+{
+#ifdef FEAT_XCLIPBOARD
+# ifdef FEAT_GUI
+    if (gui.in_use)
+	return clip_mch_own_selection(cbd);
+    else
+# endif
+	return clip_xterm_own_selection(cbd);
+#else
+    return clip_mch_own_selection(cbd);
+#endif
+}
+
+    void
+clip_own_selection(Clipboard_T *cbd)
+{
+    /*
+     * Also want to check somehow that we are reading from the keyboard rather
+     * than a mapping etc.
+     */
+#ifdef FEAT_X11
+    // Always own the selection, we might have lost it without being
+    // notified, e.g. during a ":sh" command.
+    if (cbd->available)
+    {
+	int was_owned = cbd->owned;
+
+	cbd->owned = (clip_gen_own_selection(cbd) == OK);
+	if (!was_owned && (cbd == &clip_star || cbd == &clip_plus))
+	{
+	    // May have to show a different kind of highlighting for the
+	    // selected area.  There is no specific redraw command for this,
+	    // just redraw all windows on the current buffer.
+	    if (cbd->owned
+		    && (get_real_state() == VISUAL
+					    || get_real_state() == SELECTMODE)
+		    && (cbd == &clip_star ? clip_isautosel_star()
+						      : clip_isautosel_plus())
+		    && HL_ATTR(HLF_V) != HL_ATTR(HLF_VNC))
+		redraw_curbuf_later(INVERTED_ALL);
+	}
+    }
+#else
+    // Only own the clipboard when we didn't own it yet.
+    if (!cbd->owned && cbd->available)
+	cbd->owned = (clip_gen_own_selection(cbd) == OK);
+#endif
+}
+
+    static void
+clip_gen_lose_selection(Clipboard_T *cbd)
+{
+#ifdef FEAT_XCLIPBOARD
+# ifdef FEAT_GUI
+    if (gui.in_use)
+	clip_mch_lose_selection(cbd);
+    else
+# endif
+	clip_xterm_lose_selection(cbd);
+#else
+    clip_mch_lose_selection(cbd);
+#endif
+}
+
+    void
+clip_lose_selection(Clipboard_T *cbd)
+{
+#ifdef FEAT_X11
+    int	    was_owned = cbd->owned;
+#endif
+    int     visual_selection = FALSE;
+
+    if (cbd == &clip_star || cbd == &clip_plus)
+	visual_selection = TRUE;
+
+    clip_free_selection(cbd);
+    cbd->owned = FALSE;
+    if (visual_selection)
+	clip_clear_selection(cbd);
+    clip_gen_lose_selection(cbd);
+#ifdef FEAT_X11
+    if (visual_selection)
+    {
+	// May have to show a different kind of highlighting for the selected
+	// area.  There is no specific redraw command for this, just redraw all
+	// windows on the current buffer.
+	if (was_owned
+		&& (get_real_state() == VISUAL
+					    || get_real_state() == SELECTMODE)
+		&& (cbd == &clip_star ?
+				clip_isautosel_star() : clip_isautosel_plus())
+		&& HL_ATTR(HLF_V) != HL_ATTR(HLF_VNC))
+	{
+	    update_curbuf(INVERTED_ALL);
+	    setcursor();
+	    cursor_on();
+	    out_flush_cursor(TRUE, FALSE);
+	}
+    }
+#endif
+}
+
+    static void
+clip_copy_selection(Clipboard_T *clip)
+{
+    if (VIsual_active && (State & NORMAL) && clip->available)
+    {
+	clip_update_selection(clip);
+	clip_free_selection(clip);
+	clip_own_selection(clip);
+	if (clip->owned)
+	    clip_get_selection(clip);
+	clip_gen_set_selection(clip);
+    }
+}
+
+/*
+ * Save and restore clip_unnamed before doing possibly many changes. This
+ * prevents accessing the clipboard very often which might slow down Vim
+ * considerably.
+ */
+static int global_change_count = 0; // if set, inside a start_global_changes
+static int clipboard_needs_update = FALSE; // clipboard needs to be updated
+static int clip_did_set_selection = TRUE;
+
+/*
+ * Save clip_unnamed and reset it.
+ */
+    void
+start_global_changes(void)
+{
+    if (++global_change_count > 1)
+	return;
+    clip_unnamed_saved = clip_unnamed;
+    clipboard_needs_update = FALSE;
+
+    if (clip_did_set_selection)
+    {
+	clip_unnamed = 0;
+	clip_did_set_selection = FALSE;
+    }
+}
+
+/*
+ * Return TRUE if setting the clipboard was postponed, it already contains the
+ * right text.
+ */
+    static int
+is_clipboard_needs_update()
+{
+    return clipboard_needs_update;
+}
+
+/*
+ * Restore clip_unnamed and set the selection when needed.
+ */
+    void
+end_global_changes(void)
+{
+    if (--global_change_count > 0)
+	// recursive
+	return;
+    if (!clip_did_set_selection)
+    {
+	clip_did_set_selection = TRUE;
+	clip_unnamed = clip_unnamed_saved;
+	clip_unnamed_saved = 0;
+	if (clipboard_needs_update)
+	{
+	    // only store something in the clipboard,
+	    // if we have yanked anything to it
+	    if (clip_unnamed & CLIP_UNNAMED)
+	    {
+		clip_own_selection(&clip_star);
+		clip_gen_set_selection(&clip_star);
+	    }
+	    if (clip_unnamed & CLIP_UNNAMED_PLUS)
+	    {
+		clip_own_selection(&clip_plus);
+		clip_gen_set_selection(&clip_plus);
+	    }
+	}
+    }
+    clipboard_needs_update = FALSE;
+}
+
+/*
+ * Called when Visual mode is ended: update the selection.
+ */
+    void
+clip_auto_select(void)
+{
+    if (clip_isautosel_star())
+	clip_copy_selection(&clip_star);
+    if (clip_isautosel_plus())
+	clip_copy_selection(&clip_plus);
+}
+
+/*
+ * Return TRUE if automatic selection of Visual area is desired for the *
+ * register.
+ */
+    int
+clip_isautosel_star(void)
+{
+    return (
+#ifdef FEAT_GUI
+	    gui.in_use ? (vim_strchr(p_go, GO_ASEL) != NULL) :
+#endif
+	    clip_autoselect_star);
+}
+
+/*
+ * Return TRUE if automatic selection of Visual area is desired for the +
+ * register.
+ */
+    int
+clip_isautosel_plus(void)
+{
+    return (
+#ifdef FEAT_GUI
+	    gui.in_use ? (vim_strchr(p_go, GO_ASELPLUS) != NULL) :
+#endif
+	    clip_autoselect_plus);
+}
+
+
+/*
+ * Stuff for general mouse selection, without using Visual mode.
+ */
+
+/*
+ * Compare two screen positions ala strcmp()
+ */
+    static int
+clip_compare_pos(
+    int		row1,
+    int		col1,
+    int		row2,
+    int		col2)
+{
+    if (row1 > row2) return(1);
+    if (row1 < row2) return(-1);
+    if (col1 > col2) return(1);
+    if (col1 < col2) return(-1);
+    return(0);
+}
+
+// "how" flags for clip_invert_area()
+#define CLIP_CLEAR	1
+#define CLIP_SET	2
+#define CLIP_TOGGLE	3
+
+/*
+ * Invert or un-invert a rectangle of the screen.
+ * "invert" is true if the result is inverted.
+ */
+    static void
+clip_invert_rectangle(
+	Clipboard_T	*cbd UNUSED,
+	int		row_arg,
+	int		col_arg,
+	int		height_arg,
+	int		width_arg,
+	int		invert)
+{
+    int		row = row_arg;
+    int		col = col_arg;
+    int		height = height_arg;
+    int		width = width_arg;
+
+#ifdef FEAT_PROP_POPUP
+    // this goes on top of all popup windows
+    screen_zindex = CLIP_ZINDEX;
+
+    if (col < cbd->min_col)
+    {
+	width -= cbd->min_col - col;
+	col = cbd->min_col;
+    }
+    if (width > cbd->max_col - col)
+	width = cbd->max_col - col;
+    if (row < cbd->min_row)
+    {
+	height -= cbd->min_row - row;
+	row = cbd->min_row;
+    }
+    if (height > cbd->max_row - row + 1)
+	height = cbd->max_row - row + 1;
+#endif
+#ifdef FEAT_GUI
+    if (gui.in_use)
+	gui_mch_invert_rectangle(row, col, height, width);
+    else
+#endif
+	screen_draw_rectangle(row, col, height, width, invert);
+#ifdef FEAT_PROP_POPUP
+    screen_zindex = 0;
+#endif
+}
+
+/*
+ * Invert a region of the display between a starting and ending row and column
+ * Values for "how":
+ * CLIP_CLEAR:  undo inversion
+ * CLIP_SET:    set inversion
+ * CLIP_TOGGLE: set inversion if pos1 < pos2, undo inversion otherwise.
+ * 0: invert (GUI only).
+ */
+    static void
+clip_invert_area(
+	Clipboard_T	*cbd,
+	int		row1,
+	int		col1,
+	int		row2,
+	int		col2,
+	int		how)
+{
+    int		invert = FALSE;
+    int		max_col;
+
+#ifdef FEAT_PROP_POPUP
+    max_col = cbd->max_col - 1;
+#else
+    max_col = Columns - 1;
+#endif
+
+    if (how == CLIP_SET)
+	invert = TRUE;
+
+    // Swap the from and to positions so the from is always before
+    if (clip_compare_pos(row1, col1, row2, col2) > 0)
+    {
+	int tmp_row, tmp_col;
+
+	tmp_row = row1;
+	tmp_col = col1;
+	row1	= row2;
+	col1	= col2;
+	row2	= tmp_row;
+	col2	= tmp_col;
+    }
+    else if (how == CLIP_TOGGLE)
+	invert = TRUE;
+
+    // If all on the same line, do it the easy way
+    if (row1 == row2)
+    {
+	clip_invert_rectangle(cbd, row1, col1, 1, col2 - col1, invert);
+    }
+    else
+    {
+	// Handle a piece of the first line
+	if (col1 > 0)
+	{
+	    clip_invert_rectangle(cbd, row1, col1, 1,
+						  (int)Columns - col1, invert);
+	    row1++;
+	}
+
+	// Handle a piece of the last line
+	if (col2 < max_col)
+	{
+	    clip_invert_rectangle(cbd, row2, 0, 1, col2, invert);
+	    row2--;
+	}
+
+	// Handle the rectangle that's left
+	if (row2 >= row1)
+	    clip_invert_rectangle(cbd, row1, 0, row2 - row1 + 1,
+							 (int)Columns, invert);
+    }
+}
+
+/*
+ * Start, continue or end a modeless selection.  Used when editing the
+ * command-line, in the cmdline window and when the mouse is in a popup window.
+ */
+    void
+clip_modeless(int button, int is_click, int is_drag)
+{
+    int		repeat;
+
+    repeat = ((clip_star.mode == SELECT_MODE_CHAR
+		|| clip_star.mode == SELECT_MODE_LINE)
+					      && (mod_mask & MOD_MASK_2CLICK))
+	    || (clip_star.mode == SELECT_MODE_WORD
+					     && (mod_mask & MOD_MASK_3CLICK));
+    if (is_click && button == MOUSE_RIGHT)
+    {
+	// Right mouse button: If there was no selection, start one.
+	// Otherwise extend the existing selection.
+	if (clip_star.state == SELECT_CLEARED)
+	    clip_start_selection(mouse_col, mouse_row, FALSE);
+	clip_process_selection(button, mouse_col, mouse_row, repeat);
+    }
+    else if (is_click)
+	clip_start_selection(mouse_col, mouse_row, repeat);
+    else if (is_drag)
+    {
+	// Don't try extending a selection if there isn't one.  Happens when
+	// button-down is in the cmdline and them moving mouse upwards.
+	if (clip_star.state != SELECT_CLEARED)
+	    clip_process_selection(button, mouse_col, mouse_row, repeat);
+    }
+    else // release
+	clip_process_selection(MOUSE_RELEASE, mouse_col, mouse_row, FALSE);
+}
+
+/*
+ * Update the currently selected region by adding and/or subtracting from the
+ * beginning or end and inverting the changed area(s).
+ */
+    static void
+clip_update_modeless_selection(
+    Clipboard_T    *cb,
+    int		    row1,
+    int		    col1,
+    int		    row2,
+    int		    col2)
+{
+    // See if we changed at the beginning of the selection
+    if (row1 != cb->start.lnum || col1 != (int)cb->start.col)
+    {
+	clip_invert_area(cb, row1, col1, (int)cb->start.lnum, cb->start.col,
+								 CLIP_TOGGLE);
+	cb->start.lnum = row1;
+	cb->start.col  = col1;
+    }
+
+    // See if we changed at the end of the selection
+    if (row2 != cb->end.lnum || col2 != (int)cb->end.col)
+    {
+	clip_invert_area(cb, (int)cb->end.lnum, cb->end.col, row2, col2,
+								 CLIP_TOGGLE);
+	cb->end.lnum = row2;
+	cb->end.col  = col2;
+    }
+}
+
+/*
+ * Find the starting and ending positions of the word at the given row and
+ * column.  Only white-separated words are recognized here.
+ */
+#define CHAR_CLASS(c)	(c <= ' ' ? ' ' : vim_iswordc(c))
+
+    static void
+clip_get_word_boundaries(Clipboard_T *cb, int row, int col)
+{
+    int		start_class;
+    int		temp_col;
+    char_u	*p;
+    int		mboff;
+
+    if (row >= screen_Rows || col >= screen_Columns || ScreenLines == NULL)
+	return;
+
+    p = ScreenLines + LineOffset[row];
+    // Correct for starting in the right halve of a double-wide char
+    if (enc_dbcs != 0)
+	col -= dbcs_screen_head_off(p, p + col);
+    else if (enc_utf8 && p[col] == 0)
+	--col;
+    start_class = CHAR_CLASS(p[col]);
+
+    temp_col = col;
+    for ( ; temp_col > 0; temp_col--)
+	if (enc_dbcs != 0
+		   && (mboff = dbcs_screen_head_off(p, p + temp_col - 1)) > 0)
+	    temp_col -= mboff;
+	else if (CHAR_CLASS(p[temp_col - 1]) != start_class
+		&& !(enc_utf8 && p[temp_col - 1] == 0))
+	    break;
+    cb->word_start_col = temp_col;
+
+    temp_col = col;
+    for ( ; temp_col < screen_Columns; temp_col++)
+	if (enc_dbcs != 0 && dbcs_ptr2cells(p + temp_col) == 2)
+	    ++temp_col;
+	else if (CHAR_CLASS(p[temp_col]) != start_class
+		&& !(enc_utf8 && p[temp_col] == 0))
+	    break;
+    cb->word_end_col = temp_col;
+}
+
+/*
+ * Find the column position for the last non-whitespace character on the given
+ * line at or before start_col.
+ */
+    static int
+clip_get_line_end(Clipboard_T *cbd UNUSED, int row)
+{
+    int	    i;
+
+    if (row >= screen_Rows || ScreenLines == NULL)
+	return 0;
+    for (i =
+#ifdef FEAT_PROP_POPUP
+	    cbd->max_col;
+#else
+	    screen_Columns;
+#endif
+			    i > 0; i--)
+	if (ScreenLines[LineOffset[row] + i - 1] != ' ')
+	    break;
+    return i;
+}
+
+/*
+ * Start the selection
+ */
+    void
+clip_start_selection(int col, int row, int repeated_click)
+{
+    Clipboard_T	*cb = &clip_star;
+#ifdef FEAT_PROP_POPUP
+    win_T	*wp;
+    int		row_cp = row;
+    int		col_cp = col;
+
+    wp = mouse_find_win(&row_cp, &col_cp, FIND_POPUP);
+    if (wp != NULL && WIN_IS_POPUP(wp)
+				  && popup_is_in_scrollbar(wp, row_cp, col_cp))
+	// click or double click in scrollbar does not start a selection
+	return;
+#endif
+
+    if (cb->state == SELECT_DONE)
+	clip_clear_selection(cb);
+
+    row = check_row(row);
+    col = check_col(col);
+    col = mb_fix_col(col, row);
+
+    cb->start.lnum  = row;
+    cb->start.col   = col;
+    cb->end	    = cb->start;
+    cb->origin_row  = (short_u)cb->start.lnum;
+    cb->state	    = SELECT_IN_PROGRESS;
+#ifdef FEAT_PROP_POPUP
+    if (wp != NULL && WIN_IS_POPUP(wp))
+    {
+	// Click in a popup window restricts selection to that window,
+	// excluding the border.
+	cb->min_col = wp->w_wincol + wp->w_popup_border[3];
+	cb->max_col = wp->w_wincol + popup_width(wp)
+				 - wp->w_popup_border[1] - wp->w_has_scrollbar;
+	if (cb->max_col > screen_Columns)
+	    cb->max_col = screen_Columns;
+	cb->min_row = wp->w_winrow + wp->w_popup_border[0];
+	cb->max_row = wp->w_winrow + popup_height(wp) - 1
+						   - wp->w_popup_border[2];
+    }
+    else
+    {
+	cb->min_col = 0;
+	cb->max_col = screen_Columns;
+	cb->min_row = 0;
+	cb->max_row = screen_Rows;
+    }
+#endif
+
+    if (repeated_click)
+    {
+	if (++cb->mode > SELECT_MODE_LINE)
+	    cb->mode = SELECT_MODE_CHAR;
+    }
+    else
+	cb->mode = SELECT_MODE_CHAR;
+
+#ifdef FEAT_GUI
+    // clear the cursor until the selection is made
+    if (gui.in_use)
+	gui_undraw_cursor();
+#endif
+
+    switch (cb->mode)
+    {
+	case SELECT_MODE_CHAR:
+	    cb->origin_start_col = cb->start.col;
+	    cb->word_end_col = clip_get_line_end(cb, (int)cb->start.lnum);
+	    break;
+
+	case SELECT_MODE_WORD:
+	    clip_get_word_boundaries(cb, (int)cb->start.lnum, cb->start.col);
+	    cb->origin_start_col = cb->word_start_col;
+	    cb->origin_end_col	 = cb->word_end_col;
+
+	    clip_invert_area(cb, (int)cb->start.lnum, cb->word_start_col,
+			    (int)cb->end.lnum, cb->word_end_col, CLIP_SET);
+	    cb->start.col = cb->word_start_col;
+	    cb->end.col   = cb->word_end_col;
+	    break;
+
+	case SELECT_MODE_LINE:
+	    clip_invert_area(cb, (int)cb->start.lnum, 0, (int)cb->start.lnum,
+			    (int)Columns, CLIP_SET);
+	    cb->start.col = 0;
+	    cb->end.col   = Columns;
+	    break;
+    }
+
+    cb->prev = cb->start;
+
+#ifdef DEBUG_SELECTION
+    printf("Selection started at (%ld,%d)\n", cb->start.lnum, cb->start.col);
+#endif
+}
+
+/*
+ * Continue processing the selection
+ */
+    void
+clip_process_selection(
+    int		button,
+    int		col,
+    int		row,
+    int_u	repeated_click)
+{
+    Clipboard_T	*cb = &clip_star;
+    int		diff;
+    int		slen = 1;	// cursor shape width
+
+    if (button == MOUSE_RELEASE)
+    {
+	if (cb->state != SELECT_IN_PROGRESS)
+	    return;
+
+	// Check to make sure we have something selected
+	if (cb->start.lnum == cb->end.lnum && cb->start.col == cb->end.col)
+	{
+#ifdef FEAT_GUI
+	    if (gui.in_use)
+		gui_update_cursor(FALSE, FALSE);
+#endif
+	    cb->state = SELECT_CLEARED;
+	    return;
+	}
+
+#ifdef DEBUG_SELECTION
+	printf("Selection ended: (%ld,%d) to (%ld,%d)\n", cb->start.lnum,
+		cb->start.col, cb->end.lnum, cb->end.col);
+#endif
+	if (clip_isautosel_star()
+		|| (
+#ifdef FEAT_GUI
+		    gui.in_use ? (vim_strchr(p_go, GO_ASELML) != NULL) :
+#endif
+		    clip_autoselectml))
+	    clip_copy_modeless_selection(FALSE);
+#ifdef FEAT_GUI
+	if (gui.in_use)
+	    gui_update_cursor(FALSE, FALSE);
+#endif
+
+	cb->state = SELECT_DONE;
+	return;
+    }
+
+    row = check_row(row);
+    col = check_col(col);
+    col = mb_fix_col(col, row);
+
+    if (col == (int)cb->prev.col && row == cb->prev.lnum && !repeated_click)
+	return;
+
+    /*
+     * When extending the selection with the right mouse button, swap the
+     * start and end if the position is before half the selection
+     */
+    if (cb->state == SELECT_DONE && button == MOUSE_RIGHT)
+    {
+	/*
+	 * If the click is before the start, or the click is inside the
+	 * selection and the start is the closest side, set the origin to the
+	 * end of the selection.
+	 */
+	if (clip_compare_pos(row, col, (int)cb->start.lnum, cb->start.col) < 0
+		|| (clip_compare_pos(row, col,
+					   (int)cb->end.lnum, cb->end.col) < 0
+		    && (((cb->start.lnum == cb->end.lnum
+			    && cb->end.col - col > col - cb->start.col))
+			|| ((diff = (cb->end.lnum - row) -
+						   (row - cb->start.lnum)) > 0
+			    || (diff == 0 && col < (int)(cb->start.col +
+							 cb->end.col) / 2)))))
+	{
+	    cb->origin_row = (short_u)cb->end.lnum;
+	    cb->origin_start_col = cb->end.col - 1;
+	    cb->origin_end_col = cb->end.col;
+	}
+	else
+	{
+	    cb->origin_row = (short_u)cb->start.lnum;
+	    cb->origin_start_col = cb->start.col;
+	    cb->origin_end_col = cb->start.col;
+	}
+	if (cb->mode == SELECT_MODE_WORD && !repeated_click)
+	    cb->mode = SELECT_MODE_CHAR;
+    }
+
+    // set state, for when using the right mouse button
+    cb->state = SELECT_IN_PROGRESS;
+
+#ifdef DEBUG_SELECTION
+    printf("Selection extending to (%d,%d)\n", row, col);
+#endif
+
+    if (repeated_click && ++cb->mode > SELECT_MODE_LINE)
+	cb->mode = SELECT_MODE_CHAR;
+
+    switch (cb->mode)
+    {
+	case SELECT_MODE_CHAR:
+	    // If we're on a different line, find where the line ends
+	    if (row != cb->prev.lnum)
+		cb->word_end_col = clip_get_line_end(cb, row);
+
+	    // See if we are before or after the origin of the selection
+	    if (clip_compare_pos(row, col, cb->origin_row,
+						   cb->origin_start_col) >= 0)
+	    {
+		if (col >= (int)cb->word_end_col)
+		    clip_update_modeless_selection(cb, cb->origin_row,
+			    cb->origin_start_col, row, (int)Columns);
+		else
+		{
+		    if (has_mbyte && mb_lefthalve(row, col))
+			slen = 2;
+		    clip_update_modeless_selection(cb, cb->origin_row,
+			    cb->origin_start_col, row, col + slen);
+		}
+	    }
+	    else
+	    {
+		if (has_mbyte
+			&& mb_lefthalve(cb->origin_row, cb->origin_start_col))
+		    slen = 2;
+		if (col >= (int)cb->word_end_col)
+		    clip_update_modeless_selection(cb, row, cb->word_end_col,
+			    cb->origin_row, cb->origin_start_col + slen);
+		else
+		    clip_update_modeless_selection(cb, row, col,
+			    cb->origin_row, cb->origin_start_col + slen);
+	    }
+	    break;
+
+	case SELECT_MODE_WORD:
+	    // If we are still within the same word, do nothing
+	    if (row == cb->prev.lnum && col >= (int)cb->word_start_col
+		    && col < (int)cb->word_end_col && !repeated_click)
+		return;
+
+	    // Get new word boundaries
+	    clip_get_word_boundaries(cb, row, col);
+
+	    // Handle being after the origin point of selection
+	    if (clip_compare_pos(row, col, cb->origin_row,
+		    cb->origin_start_col) >= 0)
+		clip_update_modeless_selection(cb, cb->origin_row,
+			cb->origin_start_col, row, cb->word_end_col);
+	    else
+		clip_update_modeless_selection(cb, row, cb->word_start_col,
+			cb->origin_row, cb->origin_end_col);
+	    break;
+
+	case SELECT_MODE_LINE:
+	    if (row == cb->prev.lnum && !repeated_click)
+		return;
+
+	    if (clip_compare_pos(row, col, cb->origin_row,
+		    cb->origin_start_col) >= 0)
+		clip_update_modeless_selection(cb, cb->origin_row, 0, row,
+			(int)Columns);
+	    else
+		clip_update_modeless_selection(cb, row, 0, cb->origin_row,
+			(int)Columns);
+	    break;
+    }
+
+    cb->prev.lnum = row;
+    cb->prev.col  = col;
+
+#ifdef DEBUG_SELECTION
+	printf("Selection is: (%ld,%d) to (%ld,%d)\n", cb->start.lnum,
+		cb->start.col, cb->end.lnum, cb->end.col);
+#endif
+}
+
+# if defined(FEAT_GUI) || defined(PROTO)
+/*
+ * Redraw part of the selection if character at "row,col" is inside of it.
+ * Only used for the GUI.
+ */
+    void
+clip_may_redraw_selection(int row, int col, int len)
+{
+    int		start = col;
+    int		end = col + len;
+
+    if (clip_star.state != SELECT_CLEARED
+	    && row >= clip_star.start.lnum
+	    && row <= clip_star.end.lnum)
+    {
+	if (row == clip_star.start.lnum && start < (int)clip_star.start.col)
+	    start = clip_star.start.col;
+	if (row == clip_star.end.lnum && end > (int)clip_star.end.col)
+	    end = clip_star.end.col;
+	if (end > start)
+	    clip_invert_area(&clip_star, row, start, row, end, 0);
+    }
+}
+# endif
+
+/*
+ * Called from outside to clear selected region from the display
+ */
+    void
+clip_clear_selection(Clipboard_T *cbd)
+{
+
+    if (cbd->state == SELECT_CLEARED)
+	return;
+
+    clip_invert_area(cbd, (int)cbd->start.lnum, cbd->start.col,
+				 (int)cbd->end.lnum, cbd->end.col, CLIP_CLEAR);
+    cbd->state = SELECT_CLEARED;
+}
+
+/*
+ * Clear the selection if any lines from "row1" to "row2" are inside of it.
+ */
+    void
+clip_may_clear_selection(int row1, int row2)
+{
+    if (clip_star.state == SELECT_DONE
+	    && row2 >= clip_star.start.lnum
+	    && row1 <= clip_star.end.lnum)
+	clip_clear_selection(&clip_star);
+}
+
+/*
+ * Called before the screen is scrolled up or down.  Adjusts the line numbers
+ * of the selection.  Call with big number when clearing the screen.
+ */
+    void
+clip_scroll_selection(
+    int	    rows)		// negative for scroll down
+{
+    int	    lnum;
+
+    if (clip_star.state == SELECT_CLEARED)
+	return;
+
+    lnum = clip_star.start.lnum - rows;
+    if (lnum <= 0)
+	clip_star.start.lnum = 0;
+    else if (lnum >= screen_Rows)	// scrolled off of the screen
+	clip_star.state = SELECT_CLEARED;
+    else
+	clip_star.start.lnum = lnum;
+
+    lnum = clip_star.end.lnum - rows;
+    if (lnum < 0)			// scrolled off of the screen
+	clip_star.state = SELECT_CLEARED;
+    else if (lnum >= screen_Rows)
+	clip_star.end.lnum = screen_Rows - 1;
+    else
+	clip_star.end.lnum = lnum;
+}
+
+/*
+ * Copy the currently selected area into the '*' register so it will be
+ * available for pasting.
+ * When "both" is TRUE also copy to the '+' register.
+ */
+    void
+clip_copy_modeless_selection(int both UNUSED)
+{
+    char_u	*buffer;
+    char_u	*bufp;
+    int		row;
+    int		start_col;
+    int		end_col;
+    int		line_end_col;
+    int		add_newline_flag = FALSE;
+    int		len;
+    char_u	*p;
+    int		row1 = clip_star.start.lnum;
+    int		col1 = clip_star.start.col;
+    int		row2 = clip_star.end.lnum;
+    int		col2 = clip_star.end.col;
+
+    // Can't use ScreenLines unless initialized
+    if (ScreenLines == NULL)
+	return;
+
+    /*
+     * Make sure row1 <= row2, and if row1 == row2 that col1 <= col2.
+     */
+    if (row1 > row2)
+    {
+	row = row1; row1 = row2; row2 = row;
+	row = col1; col1 = col2; col2 = row;
+    }
+    else if (row1 == row2 && col1 > col2)
+    {
+	row = col1; col1 = col2; col2 = row;
+    }
+#ifdef FEAT_PROP_POPUP
+    if (col1 < clip_star.min_col)
+	col1 = clip_star.min_col;
+    if (col2 > clip_star.max_col)
+	col2 = clip_star.max_col;
+    if (row1 > clip_star.max_row || row2 < clip_star.min_row)
+	return;
+    if (row1 < clip_star.min_row)
+	row1 = clip_star.min_row;
+    if (row2 > clip_star.max_row)
+	row2 = clip_star.max_row;
+#endif
+    // correct starting point for being on right halve of double-wide char
+    p = ScreenLines + LineOffset[row1];
+    if (enc_dbcs != 0)
+	col1 -= (*mb_head_off)(p, p + col1);
+    else if (enc_utf8 && p[col1] == 0)
+	--col1;
+
+    // Create a temporary buffer for storing the text
+    len = (row2 - row1 + 1) * Columns + 1;
+    if (enc_dbcs != 0)
+	len *= 2;	// max. 2 bytes per display cell
+    else if (enc_utf8)
+	len *= MB_MAXBYTES;
+    buffer = alloc(len);
+    if (buffer == NULL)	    // out of memory
+	return;
+
+    // Process each row in the selection
+    for (bufp = buffer, row = row1; row <= row2; row++)
+    {
+	if (row == row1)
+	    start_col = col1;
+	else
+#ifdef FEAT_PROP_POPUP
+	    start_col = clip_star.min_col;
+#else
+	    start_col = 0;
+#endif
+
+	if (row == row2)
+	    end_col = col2;
+	else
+#ifdef FEAT_PROP_POPUP
+	    end_col = clip_star.max_col;
+#else
+	    end_col = Columns;
+#endif
+
+	line_end_col = clip_get_line_end(&clip_star, row);
+
+	// See if we need to nuke some trailing whitespace
+	if (end_col >=
+#ifdef FEAT_PROP_POPUP
+		clip_star.max_col
+#else
+		Columns
+#endif
+		    && (row < row2 || end_col > line_end_col))
+	{
+	    // Get rid of trailing whitespace
+	    end_col = line_end_col;
+	    if (end_col < start_col)
+		end_col = start_col;
+
+	    // If the last line extended to the end, add an extra newline
+	    if (row == row2)
+		add_newline_flag = TRUE;
+	}
+
+	// If after the first row, we need to always add a newline
+	if (row > row1 && !LineWraps[row - 1])
+	    *bufp++ = NL;
+
+	// Safetey check for in case resizing went wrong
+	if (row < screen_Rows && end_col <= screen_Columns)
+	{
+	    if (enc_dbcs != 0)
+	    {
+		int	i;
+
+		p = ScreenLines + LineOffset[row];
+		for (i = start_col; i < end_col; ++i)
+		    if (enc_dbcs == DBCS_JPNU && p[i] == 0x8e)
+		    {
+			// single-width double-byte char
+			*bufp++ = 0x8e;
+			*bufp++ = ScreenLines2[LineOffset[row] + i];
+		    }
+		    else
+		    {
+			*bufp++ = p[i];
+			if (MB_BYTE2LEN(p[i]) == 2)
+			    *bufp++ = p[++i];
+		    }
+	    }
+	    else if (enc_utf8)
+	    {
+		int	off;
+		int	i;
+		int	ci;
+
+		off = LineOffset[row];
+		for (i = start_col; i < end_col; ++i)
+		{
+		    // The base character is either in ScreenLinesUC[] or
+		    // ScreenLines[].
+		    if (ScreenLinesUC[off + i] == 0)
+			*bufp++ = ScreenLines[off + i];
+		    else
+		    {
+			bufp += utf_char2bytes(ScreenLinesUC[off + i], bufp);
+			for (ci = 0; ci < Screen_mco; ++ci)
+			{
+			    // Add a composing character.
+			    if (ScreenLinesC[ci][off + i] == 0)
+				break;
+			    bufp += utf_char2bytes(ScreenLinesC[ci][off + i],
+									bufp);
+			}
+		    }
+		    // Skip right halve of double-wide character.
+		    if (ScreenLines[off + i + 1] == 0)
+			++i;
+		}
+	    }
+	    else
+	    {
+		STRNCPY(bufp, ScreenLines + LineOffset[row] + start_col,
+							 end_col - start_col);
+		bufp += end_col - start_col;
+	    }
+	}
+    }
+
+    // Add a newline at the end if the selection ended there
+    if (add_newline_flag)
+	*bufp++ = NL;
+
+    // First cleanup any old selection and become the owner.
+    clip_free_selection(&clip_star);
+    clip_own_selection(&clip_star);
+
+    // Yank the text into the '*' register.
+    clip_yank_selection(MCHAR, buffer, (long)(bufp - buffer), &clip_star);
+
+    // Make the register contents available to the outside world.
+    clip_gen_set_selection(&clip_star);
+
+#ifdef FEAT_X11
+    if (both)
+    {
+	// Do the same for the '+' register.
+	clip_free_selection(&clip_plus);
+	clip_own_selection(&clip_plus);
+	clip_yank_selection(MCHAR, buffer, (long)(bufp - buffer), &clip_plus);
+	clip_gen_set_selection(&clip_plus);
+    }
+#endif
+    vim_free(buffer);
+}
+
+    void
+clip_gen_set_selection(Clipboard_T *cbd)
+{
+    if (!clip_did_set_selection)
+    {
+	// Updating postponed, so that accessing the system clipboard won't
+	// hang Vim when accessing it many times (e.g. on a :g command).
+	if ((cbd == &clip_plus && (clip_unnamed_saved & CLIP_UNNAMED_PLUS))
+		|| (cbd == &clip_star && (clip_unnamed_saved & CLIP_UNNAMED)))
+	{
+	    clipboard_need