path: root/screen.c

/* $OpenBSD$ */

/*
 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>

#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "tmux.h"

/* Selected area in screen. */
struct screen_sel {
	int		 hidden;
	int		 rectangle;
	int		 modekeys;

	u_int		 sx;
	u_int		 sy;

	u_int		 ex;
	u_int		 ey;

	struct grid_cell cell;
};

/* Entry on title stack. */
struct screen_title_entry {
	char				*text;

	TAILQ_ENTRY(screen_title_entry)	 entry;
};
TAILQ_HEAD(screen_titles, screen_title_entry);

static void	screen_resize_y(struct screen *, u_int);

static void	screen_reflow(struct screen *, u_int);

/* Free titles stack. */
static void
screen_free_titles(struct screen *s)
{
	struct screen_title_entry	*title_entry;

	if (s->titles == NULL)
		return;

	while ((title_entry = TAILQ_FIRST(s->titles)) != NULL) {
		TAILQ_REMOVE(s->titles, title_entry, entry);
		free(title_entry->text);
		free(title_entry);
	}

	free(s->titles);
	s->titles = NULL;
}

/* Create a new screen. */
void
screen_init(struct screen *s, u_int sx, u_int sy, u_int hlimit)
{
	s->grid = grid_create(sx, sy, hlimit);
	s->title = xstrdup("");
	s->titles = NULL;

	s->cstyle = 0;
	s->ccolour = xstrdup("");
	s->tabs = NULL;
	s->sel = NULL;

	screen_reinit(s);
}

/* Reinitialise screen. */
void
screen_reinit(struct screen *s)
{
	s->cx = 0;
	s->cy = 0;

	s->rupper = 0;
	s->rlower = screen_size_y(s) - 1;

	s->mode = MODE_CURSOR | MODE_WRAP;

	screen_reset_tabs(s);

	grid_clear_lines(s->grid, s->grid->hsize, s->grid->sy, 8);

	screen_clear_selection(s);
	screen_free_titles(s);
}

/* Destroy a screen. */
void
screen_free(struct screen *s)
{
	free(s->sel);
	free(s->tabs);
	free(s->title);
	free(s->ccolour);

	grid_destroy(s->grid);

	screen_free_titles(s);
}

/* Reset tabs to default, eight spaces apart. */
void
screen_reset_tabs(struct screen *s)
{
	u_int	i;

	free(s->tabs);

	if ((s->tabs = bit_alloc(screen_size_x(s))) == NULL)
		fatal("bit_alloc failed");
	for (i = 8; i < screen_size_x(s); i += 8)
		bit_set(s->tabs, i);
}

/* Set screen cursor style. */
void
screen_set_cursor_style(struct screen *s, u_int style)
{
	if (style <= 6)
		s->cstyle = style;
}

/* Set screen cursor colour. */
void
screen_set_cursor_colour(struct screen *s, const char *colour)
{
	free(s->ccolour);
	s->ccolour = xstrdup(colour);
}

/* Set screen title. */
void
screen_set_title(struct screen *s, const char *title)
{
	free(s->title);
	utf8_stravis(&s->title, title, VIS_OCTAL|VIS_CSTYLE|VIS_TAB|VIS_NL);
}

/* Push the current title onto the stack. */
void
screen_push_title(struct screen *s)
{
	struct screen_title_entry *title_entry;

	if (s->titles == NULL) {
		s->titles = xmalloc(sizeof *s->titles);
		TAILQ_INIT(s->titles);
	}
	title_entry = xmalloc(sizeof *title_entry);
	title_entry->text = xstrdup(s->title);
	TAILQ_INSERT_HEAD(s->titles, title_entry, entry);
}

/*
 * Pop a title from the stack and set it as the screen title. If the stack is
 * empty, do nothing.
 */
void
screen_pop_title(struct screen *s)
{
	struct screen_title_entry *title_entry;

	if (s->titles == NULL)
		return;

	title_entry = TAILQ_FIRST(s->titles);
	if (title_entry != NULL) {
		screen_set_title(s, title_entry->text);

		TAILQ_REMOVE(s->titles, title_entry, entry);
		free(title_entry->text);
		free(title_entry);
	}
}

/* Resize screen. */
void
screen_resize(struct screen *s, u_int sx, u_int sy, int reflow)
{
	if (sx < 1)
		sx = 1;
	if (sy < 1)
		sy = 1;

	if (sx != screen_size_x(s)) {
		s->grid->sx = sx;
		screen_reset_tabs(s);
	} else
		reflow = 0;

	if (sy != screen_size_y(s))
		screen_resize_y(s, sy);

	if (reflow)
		screen_reflow(s, sx);
}

static void
screen_resize_y(struct screen *s, u_int sy)
{
	struct grid	*gd = s->grid;
	u_int		 needed, available, oldy, i;

	if (sy == 0)
		fatalx("zero size");
	oldy = screen_size_y(s);

	/*
	 * When resizing:
	 *
	 * If the height is decreasing, delete lines from the bottom until
	 * hitting the cursor, then push lines from the top into the history.
	 *
	 * When increasing, pull as many lines as possible from scrolled
	 * history (not explicitly cleared from view) to the top, then fill the
	 * remaining with blanks at the bottom.
	 */

	/* Size decreasing. */
	if (sy < oldy) {
		needed = oldy - sy;

		/* Delete as many lines as possible from the bottom. */
		available = oldy - 1 - s->cy;
		if (available > 0) {
			if (available > needed)
				available = needed;
			grid_view_delete_lines(gd, oldy - available, available,
			    8);
		}
		needed -= available;

		/*
		 * Now just increase the history size, if possible, to take
		 * over the lines which are left. If history is off, delete
		 * lines from the top.
		 */
		available = s->cy;
		if (gd->flags & GRID_HISTORY) {
			gd->hscrolled += needed;
			gd->hsize += needed;
		} else if (needed > 0 && available > 0) {
			if (available > needed)
				available = needed;
			grid_view_delete_lines(gd, 0, available, 8);
		}
		s->cy -= needed;
	}

	/* Resize line array. */
	grid_adjust_lines(gd, gd->hsize + sy);

	/* Size increasing. */
	if (sy > oldy) {
		needed = sy - oldy;

		/*
		 * Try to pull as much as possible out of scrolled history, if
		 * is is enabled.
		 */
		available = gd->hscrolled;
		if (gd->flags & GRID_HISTORY && available > 0) {
			if (available > needed)
				available = needed;
			gd->hscrolled -= available;
			gd->hsize -= available;
			s->cy += available;
		} else
			available = 0;
		needed -= available;

		/* Then fill the rest in with blanks. */
		for (i