/* vi:set ts=8 sts=4 sw=4:
 *
 * 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.
 */

/*
 * ui.c: functions that handle the user interface.
 * 1. Keyboard input stuff, and a bit of windowing stuff.  These are called
 *    before the machine specific stuff (mch_*) so that we can call the GUI
 *    stuff instead if the GUI is running.
 * 2. Clipboard stuff.
 * 3. Input buffer stuff.
 */

#include "vim.h"

    void
ui_write(s, len)
    char_u  *s;
    int	    len;
{
#ifdef USE_GUI
    if (gui.in_use && !gui.dying)
    {
	gui_write(s, len);
	if (p_wd)
	    gui_wait_for_chars(p_wd);
	return;
    }
#endif
#ifndef NO_CONSOLE
    /* Don't output anything in silent mode ("ex -s") */
    if (!silent_mode)
	mch_write(s, len);
#endif
}

#if defined(USE_GUI) || defined(PROTO)
/*
 * When executing an external program, there may be some typed characters that
 * are not consumed by it.  Give them back to ui_inchar() and they are stored
 * here for the next call.
 */
static char_u *ta_str = NULL;
static int ta_off;	    /* offset for next char to use */
static int ta_len;	    /* length of ta_str */

    void
ui_inchar_undo(s, len)
    char_u	*s;
    int		len;
{
    char_u  *new;
    int	    newlen;

    newlen = len;
    if (ta_str != NULL)
	newlen += ta_len - ta_off;
    new = alloc(newlen);
    if (new != NULL)
    {
	mch_memmove(new, ta_str + ta_off, (size_t)(ta_len - ta_off));
	mch_memmove(new + ta_len - ta_off, s, (size_t)len);
	vim_free(ta_str);
	ta_str = new;
	ta_len = newlen;
	ta_off = 0;
    }
}
#endif

/*
 * ui_inchar(): low level input funcion.
 * Get characters from the keyboard.
 * Return the number of characters that are available.
 * If "wtime" == 0 do not wait for characters.
 * If "wtime" == -1 wait forever for characters.
 * If "wtime" > 0 wait "wtime" milliseconds for a character.
 */
    int
ui_inchar(buf, maxlen, wtime)
    char_u  *buf;
    int	    maxlen;
    long    wtime;	    /* don't use "time", MIPS cannot handle it */
{
#ifdef USE_GUI
    /*
     * Use the typeahead if there is any.
     */
    if (ta_str != NULL)
    {
	if (maxlen >= ta_len - ta_off)
	{
	    mch_memmove(buf, ta_str + ta_off, (size_t)ta_len);
	    vim_free(ta_str);
	    ta_str = NULL;
	    return ta_len;
	}
	mch_memmove(buf, ta_str + ta_off, (size_t)maxlen);
	ta_off += maxlen;
	return maxlen;
    }
#endif

#ifdef NO_CONSOLE
    /* Don't wait for character input when the window hasn't been opened yet.
     * Must return something, otherwise we'll loop forever.  */
    if (!gui.in_use || gui.starting)
    {
	buf[0] = CR;
	return 1;
    }
#endif
#ifdef USE_GUI
    if (gui.in_use)
    {
	if (!gui_wait_for_chars(wtime))
	    return 0;
	return read_from_input_buf(buf, (long)maxlen);
    }
#endif
#ifndef NO_CONSOLE
    return mch_inchar(buf, maxlen, wtime);
#else
    return 0;
#endif
}

/*
 * return non-zero if a character is available
 */
    int
ui_char_avail()
{
#ifdef USE_GUI
    if (gui.in_use)
    {
	gui_mch_update();
	return !vim_is_input_buf_empty();
    }
#endif
#ifndef NO_CONSOLE
    return mch_char_avail();
#else
    return 0;
#endif
}

/*
 * Delay for the given number of milliseconds.	If ignoreinput is FALSE then we
 * cancel the delay if a key is hit.
 */
    void
ui_delay(msec, ignoreinput)
    long	msec;
    int		ignoreinput;
{
#ifdef USE_GUI
    if (gui.in_use && !ignoreinput)
	gui_wait_for_chars(msec);
    else
#endif
	mch_delay(msec, ignoreinput);
}

/*
 * If the machine has job control, use it to suspend the program,
 * otherwise fake it by starting a new shell.
 * When running the GUI iconify the window.
 */
    void
ui_suspend()
{
#ifdef USE_GUI
    if (gui.in_use)
    {
	gui_mch_iconify();
	return;
    }
#endif
    mch_suspend();
}

#if !defined(UNIX) || !defined(SIGTSTP) || defined(PROTO) || defined(__BEOS__)
/*
 * When the OS can't really suspend, call this function to start a shell.
 */
    void
suspend_shell()
{
    MSG_PUTS("new shell started\n");
    (void)mch_call_shell(NULL, SHELL_COOKED);
    need_check_timestamps = TRUE;
}
#endif

/*
 * Try to get the current window size.	Put the result in Rows and Columns.
 * Return OK when size could be determined, FAIL otherwise.
 */
    int
ui_get_winsize()
{
    int	    retval;

#ifdef USE_GUI
    if (gui.in_use)
	retval = gui_get_winsize();
    else
#endif
	retval = mch_get_winsize();

    /* adjust the default for 'lines' and 'columns' */
    if (retval == OK)
    {
	set_number_default("lines", Rows);
	set_number_default("columns", Columns);
    }
    return retval;
}

/*
 * Set the size of the window according to Rows and Columns, if possible.
 */
    void
ui_set_winsize()
{
#ifdef USE_GUI
    if (gui.in_use)
	gui_set_winsize(
# ifdef WIN32
		TRUE
# else
		FALSE
# endif
		);
    else
#endif
	mch_set_winsize();
}

    void
ui_breakcheck()
{
#ifdef USE_GUI
    if (gui.in_use)
	gui_mch_update();
    else
#endif
	mch_breakcheck();
}

/*****************************************************************************
 * 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.
 */

#ifdef USE_CLIPBOARD

#define char_class(c)	(c <= ' ' ? ' ' : vim_iswordc(c))

/*
 * 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(can_use)
    int	    can_use;
{
    clipboard.available = can_use;
    clipboard.owned = FALSE;
    clipboard.start.lnum = 0;
    clipboard.start.col = 0;
    clipboard.end.lnum = 0;
    clipboard.end.col = 0;
    clipboard.state = SELECT_CLEARED;
}

/*
 * 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()
{
    FPOS    start, end;

    /* If visual mode is only due to a redo command ("."), then ignore it */
    if (!redo_VIsual_busy && VIsual_active)
    {
	if (lt(VIsual, curwin->w_cursor))
	{
	    start = VIsual;
	    end = curwin->w_cursor;
#ifdef MULTI_BYTE
	    if (is_dbcs && mb_isbyte1(ml_get(end.lnum),end.col))
		end.col++;
#endif
	}
	else
	{
	    start = curwin->w_cursor;
	    end = VIsual;
	}
	if (!equal(clipboard.start, start) || !equal(clipboard.end, end)
					    || clipboard.vmode != VIsual_mode)
	{
	    clip_clear_selection();
	    clipboard.start = start;
	    clipboard.end = end;
	    clipboard.vmode = VIsual_mode;
	    clip_free_selection();
	    clip_own_selection();
	    clip_gen_set_selection();
	}
    }
}

    void
clip_own_selection()
{
    /*
     * Also want to check somehow that we are reading from the keyboard rather
     * than a mapping etc.
     */
    if (!clipboard.owned && clipboard.available)
    {
	clipboard.owned = (clip_gen_own_selection() == OK);
#ifdef HAVE_X11
	if (clipboard.owned
		&& get_real_state() == VISUAL
		&& clip_isautosel()
		&& hl_attr(HLF_V) != hl_attr(HLF_VNC))
	    redraw_curbuf_later(NOT_VALID);
#endif
    }
}

    void
clip_lose_selection()
{
#ifdef HAVE_X11
    int	    was_owned = clipboard.owned;
#endif

    clip_free_selection();
    clipboard.owned = FALSE;
    clip_clear_selection();
    clip_gen_lose_selection();
#ifdef HAVE_X11
    if (was_owned
	    && get_real_state() == VISUAL
	    && clip_isautosel()
	    && hl_attr(HLF_V) != hl_attr(HLF_VNC))
    {
	update_curbuf(NOT_VALID);
	setcursor();
	cursor_on();
	out_flush();
    }
#endif
}

    void
clip_copy_selection()
{
    if (VIsual_active && clipboard.available)
    {
	if (clip_isautosel())
	    clip_update_selection();
	clip_free_selection();
	clip_own_selection();
	if (clipboard.owned)
	    clip_get_selection();
	clip_gen_set_selection();
    }
}

/*
 * Called when Visual mode is ended: update the selection.
 */
    void
clip_auto_select()
{
    if (clip_isautosel())
	clip_copy_selection();
}

/*
 * Return TRUE if automatic selection of Visual area is desired.
 */
    int
clip_isautosel()
{
    return (
#ifdef USE_GUI
	    gui.in_use ? (vim_strchr(p_go, GO_ASEL) != NULL) :
#endif
	    (vim_strchr(p_cb, 't') != NULL));
}


#if defined(USE_GUI) || defined(PROTO)

/*
 * Stuff for general mouse selection, without using Visual mode.
 */

static int clip_compare_pos __ARGS((int row1, int col1, int row2, int col2));
static void clip_invert_area __ARGS((int, int, int, int));
static void clip_yank_non_visual_selection __ARGS((int, int, int, int));
static void clip_get_word_boundaries __ARGS((VimClipboard *, int, int));
static int  clip_get_line_end __ARGS((int));
static void clip_update_non_visual_selection __ARGS((VimClipboard *, int, int,
						    int, int));

/*
 * Compare two screen positions ala strcmp()
 */
    static int
clip_compare_pos(row1, col1, row2, col2)
    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);
}

/*
 * Start out the selection
 */
/* ARGSUSED */
    void
clip_start_selection(button, x, y, repeated_click, modifiers)
    int	    button;
    int	    x;
    int	    y;
    int	    repeated_click;
    int_u   modifiers;
{
    VimClipboard    *cb = &clipboard;

    if (cb->state == SELECT_DONE)
	clip_clear_selection();

    cb->start.lnum  = check_row(Y_2_ROW(y));
    cb->start.col   = check_col(X_2_COL(x));
    cb->end	    = cb->start;
    cb->origin_row  = (short_u)cb->start.lnum;
    cb->state	    = SELECT_IN_PROGRESS;

    if (repeated_click)
    {
	if (++(cb->mode) > SELECT_MODE_LINE)
	    cb->mode = SELECT_MODE_CHAR;
    }
    else
	cb->mode = SELECT_MODE_CHAR;

    /* clear the cursor until the selection is made */
    gui_undraw_cursor();

    switch (cb->mode)
    {
	case SELECT_MODE_CHAR:
	    cb->origin_start_col = cb->start.col;
	    cb->word_end_col = clip_get_line_end((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((int)cb->start.lnum, cb->word_start_col,
			    (int)cb->end.lnum, cb->word_end_col);
	    cb->start.col = cb->word_start_col;
	    cb->end.col   = cb->word_end_col;
	    break;

	case SELECT_MODE_LINE:
	    clip_invert_area((int)cb->start.lnum, 0, (int)cb->start.lnum,
			    (int)Columns);
	    cb->start.col = 0;
	    cb->end.col   = Columns;
	    break;
    }

    cb->prev = cb->start;

#ifdef DEBUG_SELECTION
    printf("Selection started at (%u,%u)\n", cb->start.lnum, cb->start.col);
#endif
}

/*
 * Continue processing the selection
 */
/* ARGSUSED */
    void
clip_process_selection(button, x, y, repeated_click, modifiers)
    int	    button;
    int	    x;
    int	    y;
    int	    repeated_click;
    int_u   modifiers;
{
    VimClipboard    *cb = &clipboard;
    int		    row;
    int_u	    col;
    int		    diff;

    if (button == MOUSE_RELEASE)
    {
	/* Check to make sure we have something selected */
	if (cb->start.lnum == cb->end.lnum && cb->start.col == cb->end.col)
	{
	    if (gui.in_use)
		gui_update_cursor(FALSE, FALSE);
	    cb->state = SELECT_CLEARED;
	    return;
	}

#ifdef DEBUG_SELECTION
	printf("Selection ended: (%u,%u) to (%u,%u)\n", cb->start.lnum,
		cb->start.col, cb->end.lnum, cb->end.col);
#endif
	clip_free_selection();
	clip_own_selection();
	clip_yank_non_visual_selection((int)cb->start.lnum, cb->start.col,
					      (int)cb->end.lnum, cb->end.col);
	clip_gen_set_selection();
	if (gui.in_use)
	    gui_update_cursor(FALSE, FALSE);

	cb->state = SELECT_DONE;
	return;
    }

    row = check_row(Y_2_ROW(y));
    col = check_col(X_2_COL(x));

    if (col == cb->prev.col && row == cb->prev.lnum)
	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 < (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)
	{
	    clip_get_word_boundaries(cb, cb->origin_row, cb->origin_start_col);
	    cb->origin_start_col = cb->word_start_col;
	    cb->origin_end_col	 = cb->word_end_col;
	}
    }

    /* 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

    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(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_non_visual_selection(cb, cb->origin_row,
			    cb->origin_start_col, row, (int)Columns);
		else
		    clip_update_non_visual_selection(cb, cb->origin_row,
			    cb->origin_start_col, row, col + 1);
	    }
	    else
	    {
		if (col >= (int)cb->word_end_col)
		    clip_update_non_visual_selection(cb, row, cb->word_end_col,
			    cb->origin_row, cb->origin_start_col + 1);
		else
		    clip_update_non_visual_selection(cb, row, col,
			    cb->origin_row, cb->origin_start_col + 1);
	    }
	    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)
		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_non_visual_selection(cb, cb->origin_row,
			cb->origin_start_col, row, cb->word_end_col);
	    else
		clip_update_non_visual_selection(cb, row, cb->word_start_col,
			cb->origin_row, cb->origin_end_col);
	    break;

	case SELECT_MODE_LINE:
	    if (row == cb->prev.lnum)
		return;

	    if (clip_compare_pos(row, col, cb->origin_row,
		    cb->origin_start_col) >= 0)
		clip_update_non_visual_selection(cb, cb->origin_row, 0, row,
			(int)Columns);
	    else
		clip_update_non_visual_selection(cb, row, 0, cb->origin_row,
			(int)Columns);
	    break;
    }

    cb->prev.lnum = row;
    cb->prev.col  = col;

#ifdef DEBUG_SELECTION
	printf("Selection is: (%u,%u) to (%u,%u)\n", cb->start.lnum,
		cb->start.col, cb->end.lnum, cb->end.col);
#endif
}

/*
 * Called after an Expose event to redraw the selection
 */
    void
clip_redraw_selection(x, y, w, h)
    int	    x;
    int	    y;
    int	    w;
    int	    h;
{
    VimClipboard    *cb = &clipboard;
    int		    row1, col1, row2, col2;
    int		    row;
    int		    start;
    int		    end;

    if (cb->state == SELECT_CLEARED)
	return;

    row1 = check_row(Y_2_ROW(y));
    col1 = check_col(X_2_COL(x));
    row2 = check_row(Y_2_ROW(y + h - 1));
    col2 = check_col(X_2_COL(x + w - 1));

    /* Limit the rows that need to be re-drawn */
    if (cb->start.lnum > row1)
	row1 = cb->start.lnum;
    if (cb->end.lnum < row2)
	row2 = cb->end.lnum;

    /* Look at each row that might need to be re-drawn */
    for (row = row1; row <= row2; row++)
    {
	/* For the first selection row, use the starting selection column */
	if (row == cb->start.lnum)
	    start = cb->start.col;
	else
	    start = 0;

	/* For the last selection row, use the ending selection column */
	if (row == cb->end.lnum)
	    end = cb->end.col;
	else
	    end = Columns;

	if (col1 > start)
	    start = col1;

	if (col2 < end)
	    end = col2 + 1;

	if (end > start)
	    gui_mch_invert_rectangle(row, start, 1, end - start);
    }
}

/*
 * Redraw the selection if character at "row,col" is inside of it.
 */
    void
clip_may_redraw_selection(row, col)
    int	row, col;
{
    if (clipboard.state != SELECT_CLEARED
	    && ((row == clipboard.start.lnum
		    && col >= (int)clipboard.start.col)
		|| row > clipboard.start.lnum)
	    && ((row == clipboard.end.lnum
		    && col < (int)clipboard.end.col)
		|| row < clipboard.end.lnum))
	clip_invert_area(row, col, row, col + 1);
}

/*
 * Called from outside to clear selected region from the display
 */
    void
clip_clear_selection()
{
    VimClipboard    *cb = &clipboard;

    if (cb->state == SELECT_CLEARED)
	return;

    clip_invert_area((int)cb->start.lnum, cb->start.col, (int)cb->end.lnum,
	    cb->end.col);
    cb->state = SELECT_CLEARED;
}

/*
 * Clear the selection if any lines from "row1" to "row2" are inside of it.
 */
    void
clip_may_clear_selection(row1, row2)
    int	row1, row2;
{
    if (clipboard.state == SELECT_DONE
	    && row2 >= clipboard.start.lnum
	    && row1 <= clipboard.end.lnum)
	clip_clear_selection();
}

/*
 * 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(rows)
    int	    rows;		/* negative for scroll down */
{
    int	    lnum;

    if (clipboard.state == SELECT_CLEARED)
	return;

    lnum = clipboard.start.lnum - rows;
    if (lnum <= 0)
	clipboard.start.lnum = 0;
    else if (lnum >= screen_Rows)	/* scrolled off of the screen */
	clipboard.state = SELECT_CLEARED;
    else
	clipboard.start.lnum = lnum;

    lnum = clipboard.end.lnum - rows;
    if (lnum < 0)			/* scrolled off of the screen */
	clipboard.state = SELECT_CLEARED;
    else if (lnum >= screen_Rows)
	clipboard.end.lnum = screen_Rows - 1;
    else
	clipboard.end.lnum = lnum;
}

/*
 * Invert a region of the display between a starting and ending row and column
 */
    static void
clip_invert_area(row1, col1, row2, col2)
    int	    row1;
    int	    col1;
    int	    row2;
    int	    col2;
{
    /* 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;
    }

    /* If all on the same line, do it the easy way */
    if (row1 == row2)
    {
	gui_mch_invert_rectangle(row1, col1, 1, col2 - col1);
	return;
    }

    /* Handle a piece of the first line */
    if (col1 > 0)
    {
	gui_mch_invert_rectangle(row1, col1, 1, (int)Columns - col1);
	row1++;
    }

    /* Handle a piece of the last line */
    if (col2 < Columns - 1)
    {
	gui_mch_invert_rectangle(row2, 0, 1, col2);
	row2--;
    }

    /* Handle the rectangle thats left */
    if (row2 >= row1)
	gui_mch_invert_rectangle(row1, 0, row2 - row1 + 1, (int)Columns);
}

/*
 * Yank the currently selected area into the special selection buffer so it
 * will be available for pasting.
 */
    static void
clip_yank_non_visual_selection(row1, col1, row2, col2)
    int	    row1;
    int	    col1;
    int	    row2;
    int	    col2;
{
    char_u  *buffer;
    char_u  *bufp;
    int	    row;
    int	    start_col;
    int	    end_col;
    int	    line_end_col;
    int	    add_newline_flag = FALSE;

    /*
     * 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;
    }

    /* Create a temporary buffer for storing the text */
    buffer = lalloc((row2 - row1 + 1) * Columns + 1, TRUE);
    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
	    start_col = 0;

	if (row == row2)
	    end_col = col2;
	else
	    end_col = Columns;

	line_end_col = clip_get_line_end(row);

	/* See if we need to nuke some trailing whitespace */
	if (end_col >= Columns && (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)
	    *bufp++ = NL;

	if (row < screen_Rows && end_col <= screen_Columns)
	{
	    STRNCPY(bufp, &LinePointers[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;

    clip_yank_selection(MCHAR, buffer, (long)(bufp - buffer));
    vim_free(buffer);
}

/*
 * Find the starting and ending positions of the word at the given row and
 * column.
 */
    static void
clip_get_word_boundaries(cb, row, col)
    VimClipboard    *cb;
    int		    row;
    int		    col;
{
    char    start_class;
    int	    temp_col;

    if (row >= screen_Rows || col >= screen_Columns)
	return;

    start_class = char_class(LinePointers[row][col]);

    temp_col = col;
    for ( ; temp_col > 0; temp_col--)
	if (char_class(LinePointers[row][temp_col - 1]) != start_class)
	    break;

    cb->word_start_col = temp_col;

    temp_col = col;
    for ( ; temp_col < screen_Columns; temp_col++)
	if (char_class(LinePointers[row][temp_col]) != start_class)
	    break;
    cb->word_end_col = temp_col;

#ifdef DEBUG_SELECTION
    printf("Current word: col %u to %u\n", cb->word_start_col,
	    cb->word_end_col);
#endif
}

/*
 * Find the column position for the last non-whitespace character on the given
 * line.
 */
    static int
clip_get_line_end(row)
    int		row;
{
    int	    i;

    if (row >= screen_Rows)
	return 0;
    for (i = screen_Columns; i > 0; i--)
	if (LinePointers[row][i - 1] != ' ')
	    break;
    return i;
}

/*
 * 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_non_visual_selection(cb, row1, col1, row2, col2)
    VimClipboard    *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(row1, col1, (int)cb->start.lnum, cb->start.col);
	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(row2, col2, (int)cb->end.lnum, cb->end.col);
	cb->end.lnum = row2;
	cb->end.col  = col2;
    }
}

#else /* If USE_GUI not defined */

/*
 * Called from outside to clear selected region from the display
 */
    void
clip_clear_selection()
{
    /*
     * Dummy version for now... the point of this code is to set the selected
     * area back to "normal" colour if we are clearing the selection. As we
     * don't have GUI-style mouse selection, we can ignore this for now.
     * Eventually we could actually invert the area in a terminal by redrawing
     * in reverse mode, but we don't do that yet.
     */
    clipboard.state = SELECT_CLEARED;
}
#endif /* USE_GUI */

    int
clip_gen_own_selection()
{
#ifdef XTERM_CLIP
# ifdef USE_GUI
    if (gui.in_use)
	return clip_mch_own_selection();
    else
# endif
	return clip_xterm_own_selection();
#else
    return clip_mch_own_selection();
#endif
}

    void
clip_gen_lose_selection()
{
#ifdef XTERM_CLIP
# ifdef USE_GUI
    if (gui.in_use)
	clip_mch_lose_selection();
    else
# endif
	clip_xterm_lose_selection();
#else
    clip_mch_lose_selection();
#endif
}

    void
clip_gen_set_selection()
{
#ifdef XTERM_CLIP
# ifdef USE_GUI
    if (gui.in_use)
	clip_mch_set_selection();
    else
# endif
	clip_xterm_set_selection();
#else
    clip_mch_set_selection();
#endif
}

    void
clip_gen_request_selection()
{
#ifdef XTERM_CLIP
# ifdef USE_GUI
    if (gui.in_use)
	clip_mch_request_selection();
    else
# endif
	clip_xterm_request_selection();
#else
    clip_mch_request_selection();
#endif
}

#endif /* USE_CLIPBOARD */

/*****************************************************************************
 * Functions that handle the input buffer.
 * This is used for any GUI version, and the unix terminal version.
 *
 * For Unix, the input characters are buffered to be able to check for a
 * CTRL-C.  This should be done with signals, but I don't know how to do that
 * in a portable way for a tty in RAW mode.
 */

#if defined(UNIX) || defined(USE_GUI) || defined(OS2) || defined(VMS)

/*
 * Internal typeahead buffer.  Includes extra space for long key code
 * descriptions which would otherwise overflow.  The buffer is considered full
 * when only this extra space (or part of it) remains.
 */
#define INBUFLEN 250

static char_u	inbuf[INBUFLEN + MAX_KEY_CODE_LEN];
static int	inbufcount = 0;	    /* number of chars in inbuf[] */

/*
 * vim_is_input_buf_full(), vim_is_input_buf_empty(), add_to_input_buf(), and
 * trash_input_buf() are functions for manipulating the input buffer.  These
 * are used by the gui_* calls when a GUI is used to handle keyboard input.
 */

    int
vim_is_input_buf_full()
{
    return (inbufcount >= INBUFLEN);
}

    int
vim_is_input_buf_empty()
{
    return (inbufcount == 0);
}

#if defined(HAVE_OLE) || defined(PROTO)
    int
vim_free_in_input_buf()
{
    return (INBUFLEN - inbufcount);
}
#endif

/* Add the given bytes to the input buffer */
    void
add_to_input_buf(s, len)
    char_u  *s;
    int	    len;
{
    if (inbufcount + len > INBUFLEN + MAX_KEY_CODE_LEN)
	return;	    /* Shouldn't ever happen! */

#ifdef HANGUL_INPUT
    if ((State & (INSERT|CMDLINE)) && hangul_input_state_get())
	if ((len = hangul_input_process(s, len)) == 0)
	    return;
#endif

    while (len--)
	inbuf[inbufcount++] = *s++;
}

#if defined(HANGUL_INPUT) || defined(PROTO)
    void
push_raw_key (s, len)
    char_u  *s;
    int	    len;
{
    while (len--)
	inbuf[inbufcount++] = *s++;
}
#endif

#if defined(USE_GUI) || defined(PROTO)
/* Remove everything from the input buffer.  Called when ^C is found */
    void
trash_input_buf()
{
    inbufcount = 0;
}
#endif

/*
 * Read as much data from the input buffer as possible up to maxlen, and store
 * it in buf.
 * Note: this function used to be Read() in unix.c
 */
    int
read_from_input_buf(buf, maxlen)
    char_u  *buf;
    long    maxlen;
{
    if (inbufcount == 0)	/* if the buffer is empty, fill it */
	fill_input_buf(TRUE);
    if (maxlen > inbufcount)
	maxlen = inbufcount;
    mch_memmove(buf, inbuf, (size_t)maxlen);
    inbufcount -= maxlen;
    if (inbufcount)
	mch_memmove(inbuf, inbuf + maxlen, (size_t)inbufcount);
    return (int)maxlen;
}

    void
fill_input_buf(exit_on_error)
    int	exit_on_error;
{
#if defined(UNIX) || defined(OS2) || defined(VMS)
    int		len;
    int		try;
    static int	did_read_something = FALSE;
#endif
#ifdef VMS
    extern char ibuf[];
#endif

#ifdef USE_GUI
    if (gui.in_use)
    {
	gui_mch_update();
	return;
    }
#endif
#if defined(UNIX) || defined(OS2) || defined(VMS)
    if (vim_is_input_buf_full())
	return;
    /*
     * Fill_input_buf() is only called when we really need a character.
     * If we can't get any, but there is some in the buffer, just return.
     * If we can't get any, and there isn't any in the buffer, we give up and
     * exit Vim.
     */
# ifdef __BEOS__
    /*
     * On the BeBox version (for now), all input is secretly performed within
     * beos_select() which is called from RealWaitForChar().
     */
    while (!vim_is_input_buf_full() && RealWaitForChar(read_cmd_fd, 0, NULL))
	    ;
    len = inbufcount;
    inbufcount = 0;
# else

#  ifdef USE_SNIFF
    if (sniff_request_waiting)
    {
	add_to_input_buf((char_u *)"\233sniff",6); /* results in K_SNIFF */
	sniff_request_waiting = 0;
	want_sniff_request = 0;
	return;
    }
#  endif
#  ifdef VMS
    while (!vim_is_input_buf_full() && RealWaitForChar(0, 0L))
    {
	add_to_input_buf((char_u *)ibuf, 1);
    }
    if (inbufcount < 1 && !exit_on_error)
	return;
    len = inbufcount;
    inbufcount = 0;
#  else

    for (try = 0; try < 100; ++try)
    {
	len = read(read_cmd_fd, (char *)inbuf + inbufcount,
					     (size_t)(INBUFLEN - inbufcount));
	if (len > 0 || got_int)
	    break;
	/*
	 * If reading stdin results in an error, continue reading stderr.
	 * This helps when using "foo | xargs vim".
	 */
	if (!did_read_something && !isatty(read_cmd_fd) && read_cmd_fd == 0)
	    read_cmd_fd = 2;
	if (!exit_on_error)
	    return;
    }
#  endif /* VMS */
# endif
    if (len <= 0 && !got_int)
	read_error_exit();
    did_read_something = TRUE;
    if (got_int)
    {
	inbuf[inbufcount] = 3;
	inbufcount = 1;
    }
    else
	while (len-- > 0)
	{
	    /*
	     * if a CTRL-C was typed, remove it from the buffer and set got_int
	     */
	    if (inbuf[inbufcount] == 3)
	    {
		/* remove everything typed before the CTRL-C */
		mch_memmove(inbuf, inbuf + inbufcount, (size_t)(len + 1));
		inbufcount = 0;
		got_int = TRUE;
	    }
	    ++inbufcount;
	}
#endif /* UNIX or OS2 or VMS*/
}
#endif /* defined(UNIX) || defined(USE_GUI) || defined(OS2)  || defined(VMS) */

/*
 * Exit because of an input read error.
 */
    void
read_error_exit()
{
    if (silent_mode)	/* Normal way to exit for "ex -s" */
	getout(0);
    STRCPY(IObuff, "Vim: Error reading input, exiting...\n");
    preserve_exit();
}

#if defined(CURSOR_SHAPE) || defined(PROTO)
/*
 * May update the shape of the cursor.
 */
    void
ui_cursor_shape()
{
#ifdef USE_GUI
    if (gui.in_use)
	gui_upd_cursor_shape();
#endif
#ifdef MCH_CURSOR_SHAPE
    mch_update_cursor();
#endif
}
#endif

#if defined(XTERM_CLIP) || defined(USE_GUI) || defined(PROTO)
/*
 * Check bounds for column number
 */
    int
check_col(col)
    int	    col;
{
    if (col < 0)
	return 0;
    if (col >= (int)screen_Columns)
	return (int)screen_Columns - 1;
    return col;
}

/*
 * Check bounds for row number
 */
    int
check_row(row)
    int	    row;
{
    if (row < 0)
	return 0;
    if (row >= (int)screen_Rows)
	return (int)screen_Rows - 1;
    return row;
}
#endif

/*
 * Stuff for the X clipboard.  Shared between VMS and Unix.
 */

#if defined(XTERM_CLIP) || defined(USE_GUI_X11) || defined(PROTO)
# include <X11/Xatom.h>
# include <X11/Intrinsic.h>

# if defined(USE_GUI) && defined(XTERM_CLIP)
#  define X_DISPLAY	gui.in_use ? gui.dpy : xterm_dpy
# else
#  ifdef USE_GUI
#   define X_DISPLAY	gui.dpy
#  else
#   define X_DISPLAY	xterm_dpy
#  endif
# endif

/*
 * Open the application context (if it hasn't been opened yet).
 * Used for Motif and Athena GUI and the xterm clipboard.
 */
    void
open_app_context()
{
    if (app_context == NULL)
    {
	XtToolkitInitialize();
	app_context = XtCreateApplicationContext();
    }
}

    void
x11_setup_atoms(dpy)
    Display	*dpy;
{
    clipboard.xatom = XInternAtom(dpy, "_VIM_TEXT", False);
    clipboard.xa_compound_text = XInternAtom(dpy, "COMPOUND_TEXT", False);
    clipboard.xa_text = XInternAtom(dpy, "TEXT", False);
    clipboard.xa_targets = XInternAtom(dpy, "TARGETS", False);
}

/*
 * X Selection stuff, for cutting and pasting text to other windows.
 */

static void  clip_x11_request_selection_cb __ARGS((Widget, XtPointer, Atom *, Atom *, XtPointer, long_u *, int *));

/* ARGSUSED */
    static void
clip_x11_request_selection_cb(w, success, selection, type, value, length,
			      format)
    Widget	w;
    XtPointer	success;
    Atom	*selection;
    Atom	*type;
    XtPointer	value;
    long_u	*length;
    int		*format;
{
    int		motion_type;
    long_u	len;
    char_u	*p;
    char	**text_list = NULL;

    if (value == NULL || *length == 0)
    {
	clip_free_selection();	/* ??? */
	*(int *)success = FALSE;
	return;
    }
    motion_type = MCHAR;
    p = (char_u *)value;
    len = *length;
    if (*type == clipboard.xatom)
    {
	motion_type = *p++;
	len--;
    }
    else if (*type == clipboard.xa_compound_text || (
#ifdef MULTI_BYTE
		is_dbcs &&
#endif
		*type == clipboard.xa_text))
    {
	XTextProperty	text_prop;
	int		n_text = 0;
	int		status;

	text_prop.value = (unsigned char *)value;
	text_prop.encoding = *type;
	text_prop.format = *format;
	text_prop.nitems = STRLEN(value);
	status = XmbTextPropertyToTextList(X_DISPLAY, &text_prop,
							 &text_list, &n_text);
	if (status != Success || n_text < 1)
	{
	    *(int *)success = FALSE;
	    return;
	}
	p = (char_u *)text_list[0];
	len = STRLEN(p);
    }
    clip_yank_selection(motion_type, p, (long)len);

    if (text_list != NULL)
	XFreeStringList(text_list);

    XtFree((char *)value);
    *(int *)success = TRUE;
}

    void
clip_x11_request_selection(myShell, dpy)
    Widget	myShell;
    Display	*dpy;
{
    XEvent	event;
    Atom	type;
    static int	success;
    int		i;

    for (i = 0; i < 4; i++)
    {
	switch (i)
	{
	    case 0:  type = clipboard.xatom;
	    case 1:  type = clipboard.xa_compound_text;
	    case 2:  type = clipboard.xa_text;
	    default: type = XA_STRING;
	}
	XtGetSelectionValue(myShell, XA_PRIMARY, type,
	    clip_x11_request_selection_cb, (XtPointer)&success, CurrentTime);

	/* Do we need this?: */
	XFlush(dpy);

	/*
	 * Wait for result of selection request, otherwise if we type more
	 * characters, then they will appear before the one that requested the
	 * paste!  Don't worry, we will catch up with any other events later.
	 */
	for (;;)
	{
	    if (XCheckTypedEvent(dpy, SelectionNotify, &event))
		break;

	    /* Do we need this?: */
	    XSync(dpy, False);
	}

	/* this is where clip_x11_request_selection_cb() is actually called */
	XtDispatchEvent(&event);

	if (success)
	    return;
    }
}

static Boolean	clip_x11_convert_selection_cb __ARGS((Widget, Atom *, Atom *, Atom *, XtPointer *, long_u *, int *));

/* ARGSUSED */
    static Boolean
clip_x11_convert_selection_cb(w, selection, target, type, value, length, format)
    Widget	w;
    Atom	*selection;
    Atom	*target;
    Atom	*type;
    XtPointer	*value;
    long_u	*length;
    int		*format;
{
    char_u	*string;
    char_u	*result;
    int		motion_type;

    if (!clipboard.owned)
	return False;	    /* Shouldn't ever happen */

    /* requestor wants to know what target types we support */
    if (*target == clipboard.xa_targets)
    {
	Atom *array;

	if ((array = (Atom *)XtMalloc((unsigned)(sizeof(Atom) * 5))) == NULL)
	    return False;
	*value = (XtPointer)array;
	array[0] = XA_STRING;
	array[1] = clipboard.xa_targets;
	array[2] = clipboard.xatom;
	array[3] = clipboard.xa_text;
	array[4] = clipboard.xa_compound_text;
	*type = XA_ATOM;
	*format = sizeof(Atom) * 8;
	*length = 5;
	return True;
    }

    if (       *target != XA_STRING
	    && *target != clipboard.xatom
	    && *target != clipboard.xa_text
	    && *target != clipboard.xa_compound_text)
	return False;

    clip_get_selection();
    motion_type = clip_convert_selection(&string, length);
    if (motion_type < 0)
	return False;

    /* For our own format, the first byte contains the motion type */
    if (*target == clipboard.xatom)
	(*length)++;

    *value = XtMalloc((Cardinal)*length);
    result = (char_u *)*value;
    if (result == NULL)
    {
	vim_free(string);
	return False;
    }

    if (*target == XA_STRING)
    {
	mch_memmove(result, string, (size_t)(*length));
	*type = XA_STRING;
    }
    else if (*target == clipboard.xa_compound_text
	    || *target == clipboard.xa_text)
    {
	XTextProperty	text_prop;
	char		*string_nt = (char *)alloc((unsigned)*length + 1);

	/* create NUL terminated string which XmbTextListToTextProperty wants */
	mch_memmove(string_nt, string, (size_t)*length);
	string_nt[*length] = NUL;
	XmbTextListToTextProperty(X_DISPLAY, (char **)&string_nt, 1,
					      XCompoundTextStyle, &text_prop);
	vim_free(string_nt);
	XtFree(*value);			/* replace with COMPOUND text */
	*value = (XtPointer)(text_prop.value);	/*    from plain text */
	*length = text_prop.nitems;
	*type = clipboard.xa_compound_text;
    }
    else
    {
	result[0] = motion_type;
	mch_memmove(result + 1, string, (size_t)(*length - 1));
	*type = clipboard.xatom;
    }
    *format = 8;	    /* 8 bits per char */
    vim_free(string);
    return True;
}

static void  clip_x11_lose_ownership_cb __ARGS((Widget, Atom *));

/* ARGSUSED */
    static void
clip_x11_lose_ownership_cb(w, selection)
    Widget  w;
    Atom    *selection;
{
    clip_lose_selection();
}

    void
clip_x11_lose_selection(myShell)
    Widget	myShell;
{
    XtDisownSelection(myShell, XA_PRIMARY, CurrentTime);
}

    int
clip_x11_own_selection(myShell)
    Widget	myShell;
{
    if (XtOwnSelection(myShell, XA_PRIMARY, CurrentTime,
	    clip_x11_convert_selection_cb, clip_x11_lose_ownership_cb,
	    NULL) == False)
	return FAIL;
    return OK;
}

/*
 * Send the current selection to the clipboard.  Do nothing for X because we
 * will fill in the selection only when requested by another app.
 */
    void
clip_x11_set_selection()
{
}
#endif
