Adding upstream version 3.3a.upstream/3.3a

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1461 insertions, 0 deletions

diff --git a/grid.c b/grid.c
new file mode 100644
index 0000000..1109ac5
--- /dev/null
+++ b/grid.c
@@ -0,0 +1,1461 @@
+/* $OpenBSD$ */
+
+/*
+ * Copyright (c) 2008 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 "tmux.h"
+
+/*
+ * Grid data. This is the basic data structure that represents what is shown on
+ * screen.
+ *
+ * A grid is a grid of cells (struct grid_cell). Lines are not allocated until
+ * cells in that line are written to. The grid is split into history and
+ * viewable data with the history starting at row (line) 0 and extending to
+ * (hsize - 1); from hsize to hsize + (sy - 1) is the viewable data. All
+ * functions in this file work on absolute coordinates, grid-view.c has
+ * functions which work on the screen data.
+ */
+
+/* Default grid cell data. */
+const struct grid_cell grid_default_cell = {
+	{ { ' ' }, 0, 1, 1 }, 0, 0, 8, 8, 0
+};
+
+/*
+ * Padding grid cell data. Padding cells are the only zero width cell that
+ * appears in the grid - because of this, they are always extended cells.
+ */
+static const struct grid_cell grid_padding_cell = {
+	{ { '!' }, 0, 0, 0 }, 0, GRID_FLAG_PADDING, 8, 8, 0
+};
+
+/* Cleared grid cell data. */
+static const struct grid_cell grid_cleared_cell = {
+	{ { ' ' }, 0, 1, 1 }, 0, GRID_FLAG_CLEARED, 8, 8, 0
+};
+static const struct grid_cell_entry grid_cleared_entry = {
+	GRID_FLAG_CLEARED, { .data = { 0, 8, 8, ' ' } }
+};
+
+/* Store cell in entry. */
+static void
+grid_store_cell(struct grid_cell_entry *gce, const struct grid_cell *gc,
+    u_char c)
+{
+	gce->flags = (gc->flags & ~GRID_FLAG_CLEARED);
+
+	gce->data.fg = gc->fg & 0xff;
+	if (gc->fg & COLOUR_FLAG_256)
+		gce->flags |= GRID_FLAG_FG256;
+
+	gce->data.bg = gc->bg & 0xff;
+	if (gc->bg & COLOUR_FLAG_256)
+		gce->flags |= GRID_FLAG_BG256;
+
+	gce->data.attr = gc->attr;
+	gce->data.data = c;
+}
+
+/* Check if a cell should be an extended cell. */
+static int
+grid_need_extended_cell(const struct grid_cell_entry *gce,
+    const struct grid_cell *gc)
+{
+	if (gce->flags & GRID_FLAG_EXTENDED)
+		return (1);
+	if (gc->attr > 0xff)
+		return (1);
+	if (gc->data.size != 1 || gc->data.width != 1)
+		return (1);
+	if ((gc->fg & COLOUR_FLAG_RGB) || (gc->bg & COLOUR_FLAG_RGB))
+		return (1);
+	if (gc->us != 0) /* only supports 256 or RGB */
+		return (1);
+	return (0);
+}
+
+/* Get an extended cell. */
+static void
+grid_get_extended_cell(struct grid_line *gl, struct grid_cell_entry *gce,
+    int flags)
+{
+	u_int at = gl->extdsize + 1;
+
+	gl->extddata = xreallocarray(gl->extddata, at, sizeof *gl->extddata);
+	gl->extdsize = at;
+
+	gce->offset = at - 1;
+	gce->flags = (flags | GRID_FLAG_EXTENDED);
+}
+
+/* Set cell as extended. */
+static struct grid_extd_entry *
+grid_extended_cell(struct grid_line *gl, struct grid_cell_entry *gce,
+    const struct grid_cell *gc)
+{
+	struct grid_extd_entry	*gee;
+	int			 flags = (gc->flags & ~GRID_FLAG_CLEARED);
+	utf8_char		 uc;
+
+	if (~gce->flags & GRID_FLAG_EXTENDED)
+		grid_get_extended_cell(gl, gce, flags);
+	else if (gce->offset >= gl->extdsize)
+		fatalx("offset too big");
+	gl->flags |= GRID_LINE_EXTENDED;
+
+	utf8_from_data(&gc->data, &uc);
+
+	gee = &gl->extddata[gce->offset];
+	gee->data = uc;
+	gee->attr = gc->attr;
+	gee->flags = flags;
+	gee->fg = gc->fg;
+	gee->bg = gc->bg;
+	gee->us = gc->us;
+	return (gee);
+}
+
+/* Free up unused extended cells. */
+static void
+grid_compact_line(struct grid_line *gl)
+{
+	int			 new_extdsize = 0;
+	struct grid_extd_entry	*new_extddata;
+	struct grid_cell_entry	*gce;
+	struct grid_extd_entry	*gee;
+	u_int			 px, idx;
+
+	if (gl->extdsize == 0)
+		return;
+
+	for (px = 0; px < gl->cellsize; px++) {
+		gce = &gl->celldata[px];
+		if (gce->flags & GRID_FLAG_EXTENDED)
+			new_extdsize++;
+	}
+
+	if (new_extdsize == 0) {
+		free(gl->extddata);
+		gl->extddata = NULL;
+		gl->extdsize = 0;
+		return;
+	}
+	new_extddata = xreallocarray(NULL, new_extdsize, sizeof *gl->extddata);
+
+	idx = 0;
+	for (px = 0; px < gl->cellsize; px++) {
+		gce = &gl->celldata[px];
+		if (gce->flags & GRID_FLAG_EXTENDED) {
+			gee = &gl->extddata[gce->offset];
+			memcpy(&new_extddata[idx], gee, sizeof *gee);
+			gce->offset = idx++;
+		}
+	}
+
+	free(gl->extddata);
+	gl->extddata = new_extddata;
+	gl->extdsize = new_extdsize;
+}
+
+/* Get line data. */
+struct grid_line *
+grid_get_line(struct grid *gd, u_int line)
+{
+	return (&gd->linedata[line]);
+}
+
+/* Adjust number of lines. */
+void
+grid_adjust_lines(struct grid *gd, u_int lines)
+{
+	gd->linedata = xreallocarray(gd->linedata, lines, sizeof *gd->linedata);
+}
+
+/* Copy default into a cell. */
+static void
+grid_clear_cell(struct grid *gd, u_int px, u_int py, u_int bg)
+{
+	struct grid_line	*gl = &gd->linedata[py];
+	struct grid_cell_entry	*gce = &gl->celldata[px];
+	struct grid_extd_entry	*gee;
+
+	memcpy(gce, &grid_cleared_entry, sizeof *gce);
+	if (bg != 8) {
+		if (bg & COLOUR_FLAG_RGB) {
+			grid_get_extended_cell(gl, gce, gce->flags);
+			gee = grid_extended_cell(gl, gce, &grid_cleared_cell);
+			gee->bg = bg;
+		} else {
+			if (bg & COLOUR_FLAG_256)
+				gce->flags |= GRID_FLAG_BG256;
+			gce->data.bg = bg;
+		}
+	}
+}
+
+/* Check grid y position. */
+static int
+grid_check_y(struct grid *gd, const char *from, u_int py)
+{
+	if (py >= gd->hsize + gd->sy) {
+		log_debug("%s: y out of range: %u", from, py);
+		return (-1);
+	}
+	return (0);
+}
+
+/* Check if two styles are (visibly) the same. */
+int
+grid_cells_look_equal(const struct grid_cell *gc1, const struct grid_cell *gc2)
+{
+	if (gc1->fg != gc2->fg || gc1->bg != gc2->bg)
+		return (0);
+	if (gc1->attr != gc2->attr || gc1->flags != gc2->flags)
+		return (0);
+	return (1);
+}
+
+/* Compare grid cells. Return 1 if equal, 0 if not. */
+int
+grid_cells_equal(const struct grid_cell *gc1, const struct grid_cell *gc2)
+{
+	if (!grid_cells_look_equal(gc1, gc2))
+		return (0);
+	if (gc1->data.width != gc2->data.width)
+		return (0);
+	if (gc1->data.size != gc2->data.size)
+		return (0);
+	return (memcmp(gc1->data.data, gc2->data.data, gc1->data.size) == 0);
+}
+
+/* Free one line. */
+static void
+grid_free_line(struct grid *gd, u_int py)
+{
+	free(gd->linedata[py].celldata);
+	gd->linedata[py].celldata = NULL;
+	free(gd->linedata[py].extddata);
+	gd->linedata[py].extddata = NULL;
+}
+
+/* Free several lines. */
+static void
+grid_free_lines(struct grid *gd, u_int py, u_int ny)
+{
+	u_int	yy;
+
+	for (yy = py; yy < py + ny; yy++)
+		grid_free_line(gd, yy);
+}
+
+/* Create a new grid. */
+struct grid *
+grid_create(u_int sx, u_int sy, u_int hlimit)
+{
+	struct grid	*gd;
+
+	gd = xmalloc(sizeof *gd);
+	gd->sx = sx;
+	gd->sy = sy;
+
+	if (hlimit != 0)
+		gd->flags = GRID_HISTORY;
+	else
+		gd->flags = 0;
+
+	gd->hscrolled = 0;
+	gd->hsize = 0;
+	gd->hlimit = hlimit;
+
+	if (gd->sy != 0)
+		gd->linedata = xcalloc(gd->sy, sizeof *gd->linedata);
+	else
+		gd->linedata = NULL;
+
+	return (gd);
+}
+
+/* Destroy grid. */
+void
+grid_destroy(struct grid *gd)
+{
+	grid_free_lines(gd, 0, gd->hsize + gd->sy);
+
+	free(gd->linedata);
+
+	free(gd);
+}
+
+/* Compare grids. */
+int
+grid_compare(struct grid *ga, struct grid *gb)
+{
+	struct grid_line	*gla, *glb;
+	struct grid_cell	 gca, gcb;
+	u_int			 xx, yy;
+
+	if (ga->sx != gb->sx || ga->sy != gb->sy)
+		return (1);
+
+	for (yy = 0; yy < ga->sy; yy++) {
+		gla = &ga->linedata[yy];
+		glb = &gb->linedata[yy];
+		if (gla->cellsize != glb->cellsize)
+			return (1);
+		for (xx = 0; xx < gla->cellsize; xx++) {
+			grid_get_cell(ga, xx, yy, &gca);
+			grid_get_cell(gb, xx, yy, &gcb);
+			if (!grid_cells_equal(&gca, &gcb))
+				return (1);
+		}
+	}
+
+	return (0);
+}
+
+/* Trim lines from the history. */
+static void
+grid_trim_history(struct grid *gd, u_int ny)
+{
+	grid_free_lines(gd, 0, ny);
+	memmove(&gd->linedata[0], &gd->linedata[ny],
+	    (gd->hsize + gd->sy - ny) * (sizeof *gd->linedata));
+}
+
+/*
+ * Collect lines from the history if at the limit. Free the top (oldest) 10%
+ * and shift up.
+ */
+void
+grid_collect_history(struct grid *gd)
+{
+	u_int	ny;
+
+	if (gd->hsize == 0 || gd->hsize < gd->hlimit)
+		return;
+
+	ny = gd->hlimit / 10;
+	if (ny < 1)
+		ny = 1;
+	if (ny > gd->hsize)
+		ny = gd->hsize;
+
+	/*
+	 * Free the lines from 0 to ny then move the remaining lines over
+	 * them.
+	 */
+	grid_trim_history(gd, ny);
+
+	gd->hsize -= ny;
+	if (gd->hscrolled > gd->hsize)
+		gd->hscrolled = gd->hsize;
+}
+
+/* Remove lines from the bottom of the history. */
+void
+grid_remove_history(struct grid *gd, u_int ny)
+{
+	u_int	yy;
+
+	if (ny > gd->hsize)
+		return;
+	for (yy = 0; yy < ny; yy++)
+		grid_free_line(gd, gd->hsize + gd->sy - 1 - yy);
+	gd->hsize -= ny;
+}
+
+/*
+ * Scroll the entire visible screen, moving one line into the history. Just
+ * allocate a new line at the bottom and move the history size indicator.
+ */
+void
+grid_scroll_history(struct grid *gd, u_int bg)
+{
+	u_int	yy;
+
+	yy = gd->hsize + gd->sy;
+	gd->linedata = xreallocarray(gd->linedata, yy + 1,
+	    sizeof *gd->linedata);
+	grid_empty_line(gd, yy, bg);
+
+	gd->hscrolled++;
+	grid_compact_line(&gd->linedata[gd->hsize]);
+	gd->hsize++;
+}
+
+/* Clear the history. */
+void
+grid_clear_history(struct grid *gd)
+{
+	grid_trim_history(gd, gd->hsize);
+
+	gd->hscrolled = 0;
+	gd->hsize = 0;
+
+	gd->linedata = xreallocarray(gd->linedata, gd->sy,
+	    sizeof *gd->linedata);
+}
+
+/* Scroll a region up, moving the top line into the history. */
+void
+grid_scroll_history_region(struct grid *gd, u_int upper, u_int lower, u_int bg)
+{
+	struct grid_line	*gl_history, *gl_upper;
+	u_int			 yy;
+
+	/* Create a space for a new line. */
+	yy = gd->hsize + gd->sy;
+	gd->linedata = xreallocarray(gd->linedata, yy + 1,
+	    sizeof *gd->linedata);
+
+	/* Move the entire screen down to free a space for this line. */
+	gl_history = &gd->linedata[gd->hsize];
+	memmove(gl_history + 1, gl_history, gd->sy * sizeof *gl_history);
+
+	/* Adjust the region and find its start and end. */
+	upper++;
+	gl_upper = &gd->linedata[upper];
+	lower++;
+
+	/* Move the line into the history. */
+	memcpy(gl_history, gl_upper, sizeof *gl_history);
+
+	/* Then move the region up and clear the bottom line. */
+	memmove(gl_upper, gl_upper + 1, (lower - upper) * sizeof *gl_upper);
+	grid_empty_line(gd, lower, bg);
+
+	/* Move the history offset down over the line. */
+	gd->hscrolled++;
+	gd->hsize++;
+}
+
+/* Expand line to fit to cell. */
+static void
+grid_expand_line(struct grid *gd, u_int py, u_int sx, u_int bg)
+{
+	struct grid_line	*gl;
+	u_int			 xx;
+
+	gl = &gd->linedata[py];
+	if (sx <= gl->cellsize)
+		return;
+
+	if (sx < gd->sx / 4)
+		sx = gd->sx / 4;
+	else if (sx < gd->sx / 2)
+		sx = gd->sx / 2;
+	else if (gd->sx > sx)
+		sx = gd->sx;
+
+	gl->celldata = xreallocarray(gl->celldata, sx, sizeof *gl->celldata);
+	for (xx = gl->cellsize; xx < sx; xx++)
+		grid_clear_cell(gd, xx, py, bg);
+	gl->cellsize = sx;
+}
+
+/* Empty a line and set background colour if needed. */
+void
+grid_empty_line(struct grid *gd, u_int py, u_int bg)
+{
+	memset(&gd->linedata[py], 0, sizeof gd->linedata[py]);
+	if (!COLOUR_DEFAULT(bg))
+		grid_expand_line(gd, py, gd->sx, bg);
+}
+
+/* Peek at grid line. */
+const struct grid_line *
+grid_peek_line(struct grid *gd, u_int py)
+{
+	if (grid_check_y(gd, __func__, py) != 0)
+		return (NULL);
+	return (&gd->linedata[py]);
+}
+
+/* Get cell from line. */
+static void
+grid_get_cell1(struct grid_line *gl, u_int px, struct grid_cell *gc)
+{
+	struct grid_cell_entry	*gce = &gl->celldata[px];
+	struct grid_extd_entry	*gee;
+
+	if (gce->flags & GRID_FLAG_EXTENDED) {
+		if (gce->offset >= gl->extdsize)
+			memcpy(gc, &grid_default_cell, sizeof *gc);
+		else {
+			gee = &gl->extddata[gce->offset];
+			gc->flags = gee->flags;
+			gc->attr = gee->attr;
+			gc->fg = gee->fg;
+			gc->bg = gee->bg;
+			gc->us = gee->us;
+			utf8_to_data(gee->data, &gc->data);
+		}
+		return;
+	}
+
+	gc->flags = gce->flags & ~(GRID_FLAG_FG256|GRID_FLAG_BG256);
+	gc->attr = gce->data.attr;
+	gc->fg = gce->data.fg;
+	if (gce->flags & GRID_FLAG_FG256)
+		gc->fg |= COLOUR_FLAG_256;
+	gc->bg = gce->data.bg;
+	if (gce->flags & GRID_FLAG_BG256)
+		gc->bg |= COLOUR_FLAG_256;
+	gc->us = 0;
+	utf8_set(&gc->data, gce->data.data);
+}
+
+/* Get cell for reading. */
+void
+grid_get_cell(struct grid *gd, u_int px, u_int py, struct grid_cell *gc)
+{
+	if (grid_check_y(gd, __func__, py) != 0 ||
+	    px >= gd->linedata[py].cellsize)
+		memcpy(gc, &grid_default_cell, sizeof *gc);
+	else
+		grid_get_cell1(&gd->linedata[py], px, gc);
+}
+
+/* Set cell at position. */
+void
+grid_set_cell(struct grid *gd, u_int px, u_int py, const struct grid_cell *gc)
+{
+	struct grid_line	*gl;
+	struct grid_cell_entry	*gce;
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+
+	grid_expand_line(gd, py, px + 1, 8);
+
+	gl = &gd->linedata[py];
+	if (px + 1 > gl->cellused)
+		gl->cellused = px + 1;
+
+	gce = &gl->celldata[px];
+	if (grid_need_extended_cell(gce, gc))
+		grid_extended_cell(gl, gce, gc);
+	else
+		grid_store_cell(gce, gc, gc->data.data[0]);
+}
+
+/* Set padding at position. */
+void
+grid_set_padding(struct grid *gd, u_int px, u_int py)
+{
+	grid_set_cell(gd, px, py, &grid_padding_cell);
+}
+
+/* Set cells at position. */
+void
+grid_set_cells(struct grid *gd, u_int px, u_int py, const struct grid_cell *gc,
+    const char *s, size_t slen)
+{
+	struct grid_line	*gl;
+	struct grid_cell_entry	*gce;
+	struct grid_extd_entry	*gee;
+	u_int			 i;
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+
+	grid_expand_line(gd, py, px + slen, 8);
+
+	gl = &gd->linedata[py];
+	if (px + slen > gl->cellused)
+		gl->cellused = px + slen;
+
+	for (i = 0; i < slen; i++) {
+		gce = &gl->celldata[px + i];
+		if (grid_need_extended_cell(gce, gc)) {
+			gee = grid_extended_cell(gl, gce, gc);
+			gee->data = utf8_build_one(s[i]);
+		} else
+			grid_store_cell(gce, gc, s[i]);
+	}
+}
+
+/* Clear area. */
+void
+grid_clear(struct grid *gd, u_int px, u_int py, u_int nx, u_int ny, u_int bg)
+{
+	struct grid_line	*gl;
+	u_int			 xx, yy, ox, sx;
+
+	if (nx == 0 || ny == 0)
+		return;
+
+	if (px == 0 && nx == gd->sx) {
+		grid_clear_lines(gd, py, ny, bg);
+		return;
+	}
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+	if (grid_check_y(gd, __func__, py + ny - 1) != 0)
+		return;
+
+	for (yy = py; yy < py + ny; yy++) {
+		gl = &gd->linedata[yy];
+
+		sx = gd->sx;
+		if (sx > gl->cellsize)
+			sx = gl->cellsize;
+		ox = nx;
+		if (COLOUR_DEFAULT(bg)) {
+			if (px > sx)
+				continue;
+			if (px + nx > sx)
+				ox = sx - px;
+		}
+
+		grid_expand_line(gd, yy, px + ox, 8); /* default bg first */
+		for (xx = px; xx < px + ox; xx++)
+			grid_clear_cell(gd, xx, yy, bg);
+	}
+}
+
+/* Clear lines. This just frees and truncates the lines. */
+void
+grid_clear_lines(struct grid *gd, u_int py, u_int ny, u_int bg)
+{
+	u_int	yy;
+
+	if (ny == 0)
+		return;
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+	if (grid_check_y(gd, __func__, py + ny - 1) != 0)
+		return;
+
+	for (yy = py; yy < py + ny; yy++) {
+		grid_free_line(gd, yy);
+		grid_empty_line(gd, yy, bg);
+	}
+	if (py != 0)
+		gd->linedata[py - 1].flags &= ~GRID_LINE_WRAPPED;
+}
+
+/* Move a group of lines. */
+void
+grid_move_lines(struct grid *gd, u_int dy, u_int py, u_int ny, u_int bg)
+{
+	u_int	yy;
+
+	if (ny == 0 || py == dy)
+		return;
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+	if (grid_check_y(gd, __func__, py + ny - 1) != 0)
+		return;
+	if (grid_check_y(gd, __func__, dy) != 0)
+		return;
+	if (grid_check_y(gd, __func__, dy + ny - 1) != 0)
+		return;
+
+	/* Free any lines which are being replaced. */
+	for (yy = dy; yy < dy + ny; yy++) {
+		if (yy >= py && yy < py + ny)
+			continue;
+		grid_free_line(gd, yy);
+	}
+	if (dy != 0)
+		gd->linedata[dy - 1].flags &= ~GRID_LINE_WRAPPED;
+
+	memmove(&gd->linedata[dy], &gd->linedata[py],
+	    ny * (sizeof *gd->linedata));
+
+	/*
+	 * Wipe any lines that have been moved (without freeing them - they are
+	 * still present).
+	 */
+	for (yy = py; yy < py + ny; yy++) {
+		if (yy < dy || yy >= dy + ny)
+			grid_empty_line(gd, yy, bg);
+	}
+	if (py != 0 && (py < dy || py >= dy + ny))
+		gd->linedata[py - 1].flags &= ~GRID_LINE_WRAPPED;
+}
+
+/* Move a group of cells. */
+void
+grid_move_cells(struct grid *gd, u_int dx, u_int px, u_int py, u_int nx,
+    u_int bg)
+{
+	struct grid_line	*gl;
+	u_int			 xx;
+
+	if (nx == 0 || px == dx)
+		return;
+
+	if (grid_check_y(gd, __func__, py) != 0)
+		return;
+	gl = &gd->linedata[py];
+
+	grid_expand_line(gd, py, px + nx, 8);
+	grid_expand_line(gd, py, dx + nx, 8);
+	memmove(&gl->celldata[dx], &gl->celldata[px],
+	    nx * sizeof *gl->celldata);
+	if (dx + nx > gl->cellused)
+		gl->cellused = dx + nx;
+
+	/* Wipe any cells that have been moved. */
+	for (xx = px; xx < px + nx; xx++) {
+		if (xx >= dx && xx < dx + nx)
+			continue;
+		grid_clear_cell(gd, xx, py, bg);
+	}
+}
+
+/* Get ANSI foreground sequence. */
+static size_t
+grid_string_cells_fg(const struct grid_cell *gc, int *values)
+{
+	size_t	n;
+	u_char	r, g, b;
+
+	n = 0;
+	if (gc->fg & COLOUR_FLAG_256) {
+		values[n++] = 38;
+		values[n++] = 5;
+		values[n++] = gc->fg & 0xff;
+	} else if (gc->fg & COLOUR_FLAG_RGB) {
+		values[n++] = 38;
+		values[n++] = 2;
+		colour_split_rgb(gc->fg, &r, &g, &b);
+		values[n++] = r;
+		values[n++] = g;
+		values[n++] = b;
+	} else {
+		switch (gc->fg) {
+		case 0:
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+		case 5:
+		case 6:
+		case 7:
+			values[n++] = gc->fg + 30;
+			break;
+		case 8:
+			values[n++] = 39;
+			break;
+		case 90:
+		case 91:
+		case 92:
+		case 93:
+		case 94:
+		case 95:
+		case 96:
+		case 97:
+			values[n++] = gc->fg;
+			break;
+		}
+	}
+	return (n);
+}
+
+/* Get ANSI background sequence. */
+static size_t
+grid_string_cells_bg(const struct grid_cell *gc, int *values)
+{
+	size_t	n;
+	u_char	r, g, b;
+
+	n = 0;
+	if (gc->bg & COLOUR_FLAG_256) {
+		values[n++] = 48;
+		values[n++] = 5;
+		values[n++] = gc->bg & 0xff;
+	} else if (gc->bg & COLOUR_FLAG_RGB) {
+		values[n++] = 48;
+		values[n++] = 2;
+		colour_split_rgb(gc->bg, &r, &g, &b);
+		values[n++] = r;
+		values[n++] = g;
+		values[n++] = b;
+	} else {
+		switch (gc->bg) {
+		case 0:
+		case 1:
+		case 2:
+		case 3:
+		case 4:
+		case 5:
+		case 6:
+		case 7:
+			values[n++] = gc->bg + 40;
+			break;
+		case 8:
+			values[n++] = 49;
+			break;
+		case 90:
+		case 91:
+		case 92:
+		case 93:
+		case 94:
+		case 95:
+		case 96:
+		case 97:
+			values[n++] = gc->bg + 10;
+			break;
+		}
+	}
+	return (n);
+}
+
+/* Get underscore colour sequence. */
+static size_t
+grid_string_cells_us(const struct grid_cell *gc, int *values)
+{
+	size_t	n;
+	u_char	r, g, b;
+
+	n = 0;
+	if (gc->us & COLOUR_FLAG_256) {
+		values[n++] = 58;
+		values[n++] = 5;
+		values[n++] = gc->us & 0xff;
+	} else if (gc->us & COLOUR_FLAG_RGB) {
+		values[n++] = 58;
+		values[n++] = 2;
+		colour_split_rgb(gc->us, &r, &g, &b);
+		values[n++] = r;
+		values[n++] = g;
+		values[n++] = b;
+	}
+	return (n);
+}
+
+/* Add on SGR code. */
+static void
+grid_string_cells_add_code(char *buf, size_t len, u_int n, int *s, int *newc,
+    int *oldc, size_t nnewc, size_t noldc, int escape_c0)
+{
+	u_int	i;
+	char	tmp[64];
+
+	if (nnewc != 0 &&
+	    (nnewc != noldc ||
+	    memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0 ||
+	    (n != 0 && s[0] == 0))) {
+		if (escape_c0)
+			strlcat(buf, "\\033[", len);
+		else
+			strlcat(buf, "\033[", len);
+		for (i = 0; i < nnewc; i++) {
+			if (i + 1 < nnewc)
+				xsnprintf(tmp, sizeof tmp, "%d;", newc[i]);
+			else
+				xsnprintf(tmp, sizeof tmp, "%d", newc[i]);
+			strlcat(buf, tmp, len);
+		}
+		strlcat(buf, "m", len);
+	}
+}
+
+/*
+ * Returns ANSI code to set particular attributes (colour, bold and so on)
+ * given a current state.
+ */
+static void
+grid_string_cells_code(const struct grid_cell *lastgc,
+    const struct grid_cell *gc, char *buf, size_t len, int escape_c0)
+{
+	int	oldc[64], newc[64], s[128];
+	size_t	noldc, nnewc, n, i;
+	u_int	attr = gc->attr, lastattr = lastgc->attr;
+	char	tmp[64];
+
+	struct {
+		u_int	mask;
+		u_int	code;
+	} attrs[] = {
+		{ GRID_ATTR_BRIGHT, 1 },
+		{ GRID_ATTR_DIM, 2 },
+		{ GRID_ATTR_ITALICS, 3 },
+		{ GRID_ATTR_UNDERSCORE, 4 },
+		{ GRID_ATTR_BLINK, 5 },
+		{ GRID_ATTR_REVERSE, 7 },
+		{ GRID_ATTR_HIDDEN, 8 },
+		{ GRID_ATTR_STRIKETHROUGH, 9 },
+		{ GRID_ATTR_UNDERSCORE_2, 42 },
+		{ GRID_ATTR_UNDERSCORE_3, 43 },
+		{ GRID_ATTR_UNDERSCORE_4, 44 },
+		{ GRID_ATTR_UNDERSCORE_5, 45 },
+		{ GRID_ATTR_OVERLINE, 53 },
+	};
+	n = 0;
+
+	/* If any attribute is removed, begin with 0. */
+	for (i = 0; i < nitems(attrs); i++) {
+		if (((~attr & attrs[i].mask) &&
+		    (lastattr & attrs[i].mask)) ||
+		    (lastgc->us != 0 && gc->us == 0)) {
+			s[n++] = 0;
+			lastattr &= GRID_ATTR_CHARSET;
+			break;
+		}
+	}
+	/* For each attribute that is newly set, add its code. */
+	for (i = 0; i < nitems(attrs); i++) {
+		if ((attr & attrs[i].mask) && !(lastattr & attrs[i].mask))
+			s[n++] = attrs[i].code;
+	}
+
+	/* Write the attributes. */
+	*buf = '\0';
+	if (n > 0) {
+		if (escape_c0)
+			strlcat(buf, "\\033[", len);
+		else
+			strlcat(buf, "\033[", len);
+		for (i = 0; i < n; i++) {
+			if (s[i] < 10)
+				xsnprintf(tmp, sizeof tmp, "%d", s[i]);
+			else {
+				xsnprintf(tmp, sizeof tmp, "%d:%d", s[i] / 10,
+				    s[i] % 10);
+			}
+			strlcat(buf, tmp, len);
+			if (i + 1 < n)
+				strlcat(buf, ";", len);
+		}
+		strlcat(buf, "m", len);
+	}
+
+	/* If the foreground colour changed, write its parameters. */
+	nnewc = grid_string_cells_fg(gc, newc);
+	noldc = grid_string_cells_fg(lastgc, oldc);
+	grid_string_cells_add_code(buf, len, n, s, newc, oldc, nnewc, noldc,
+	    escape_c0);
+
+	/* If the background colour changed, append its parameters. */
+	nnewc = grid_string_cells_bg(gc, newc);
+	noldc = grid_string_cells_bg(lastgc, oldc);
+	grid_string_cells_add_code(buf, len, n, s, newc, oldc, nnewc, noldc,
+	    escape_c0);
+
+	/* If the underscore colour changed, append its parameters. */
+	nnewc = grid_string_cells_us(gc, newc);
+	noldc = grid_string_cells_us(lastgc, oldc);
+	grid_string_cells_add_code(buf, len, n, s, newc, oldc, nnewc, noldc,
+	    escape_c0);
+
+	/* Append shift in/shift out if needed. */
+	if ((attr & GRID_ATTR_CHARSET) && !(lastattr & GRID_ATTR_CHARSET)) {
+		if (escape_c0)
+			strlcat(buf, "\\016", len); /* SO */
+		else
+			strlcat(buf, "\016", len);  /* SO */
+	}
+	if (!(attr & GRID_ATTR_CHARSET) && (lastattr & GRID_ATTR_CHARSET)) {
+		if (escape_c0)
+			strlcat(buf, "\\017", len); /* SI */
+		else
+			strlcat(buf, "\017", len);  /* SI */
+	}
+}
+
+/* Convert cells into a string. */
+char *
+grid_string_cells(struct grid *gd, u_int px, u_int py, u_int nx,
+    struct grid_cell **lastgc, int with_codes, int escape_c0, int trim)
+{
+	struct grid_cell	 gc;
+	static struct grid_cell	 lastgc1;
+	const char		*data;
+	char			*buf, code[128];
+	size_t			 len, off, size, codelen;
+	u_int			 xx;
+	const struct grid_line	*gl;
+
+	if (lastgc != NULL && *lastgc == NULL) {
+		memcpy(&lastgc1, &grid_default_cell, sizeof lastgc1);
+		*lastgc = &lastgc1;
+	}
+
+	len = 128;
+	buf = xmalloc(len);
+	off = 0;
+
+	gl = grid_peek_line(gd, py);
+	for (xx = px; xx < px + nx; xx++) {
+		if (gl == NULL || xx >= gl->cellused)
+			break;
+		grid_get_cell(gd, xx, py, &gc);
+		if (gc.flags & GRID_FLAG_PADDING)
+			continue;
+
+		if (with_codes) {
+			grid_string_cells_code(*lastgc, &gc, code, sizeof code,
+			    escape_c0);
+			codelen = strlen(code);
+			memcpy(*lastgc, &gc, sizeof **lastgc);
+		} else
+			codelen = 0;
+
+		data = gc.data.data;
+		size = gc.data.size;
+		if (escape_c0 && size == 1 && *data == '\\') {
+			data = "\\\\";
+			size = 2;
+		}
+
+		while (len < off + size + codelen + 1) {
+			buf = xreallocarray(buf, 2, len);
+			len *= 2;
+		}
+
+		if (codelen != 0) {
+			memcpy(buf + off, code, codelen);
+			off += codelen;
+		}
+		memcpy(buf + off, data, size);
+		off += size;
+	}
+
+	if (trim) {
+		while (off > 0 && buf[off - 1] == ' ')
+			off--;
+	}
+	buf[off] = '\0';
+
+	return (buf);
+}
+
+/*
+ * Duplicate a set of lines between two grids. Both source and destination
+ * should be big enough.
+ */
+void
+grid_duplicate_lines(struct grid *dst, u_int dy, struct grid *src, u_int sy,
+    u_int ny)
+{
+	struct grid_line	*dstl, *srcl;
+	u_int			 yy;
+
+	if (dy + ny > dst->hsize + dst->sy)
+		ny = dst->hsize + dst->sy - dy;
+	if (sy + ny > src->hsize + src->sy)
+		ny = src->hsize + src->sy - sy;
+	grid_free_lines(dst, dy, ny);
+
+	for (yy = 0; yy < ny; yy++) {
+		srcl = &src->linedata[sy];
+		dstl = &dst->linedata[dy];
+
+		memcpy(dstl, srcl, sizeof *dstl);
+		if (srcl->cellsize != 0) {
+			dstl->celldata = xreallocarray(NULL,
+			    srcl->cellsize, sizeof *dstl->celldata);
+			memcpy(dstl->celldata, srcl->celldata,
+			    srcl->cellsize * sizeof *dstl->celldata);
+		} else
+			dstl->celldata = NULL;
+		if (srcl->extdsize != 0) {
+			dstl->extdsize = srcl->extdsize;
+			dstl->extddata = xreallocarray(NULL, dstl->extdsize,
+			    sizeof *dstl->extddata);
+			memcpy(dstl->extddata, srcl->extddata, dstl->extdsize *
+			    sizeof *dstl->extddata);
+		} else
+			dstl->extddata = NULL;
+
+		sy++;
+		dy++;
+	}
+}
+
+/* Mark line as dead. */
+static void
+grid_reflow_dead(struct grid_line *gl)
+{
+	memset(gl, 0, sizeof *gl);
+	gl->flags = GRID_LINE_DEAD;
+}
+
+/* Add lines, return the first new one. */
+static struct grid_line *
+grid_reflow_add(struct grid *gd, u_int n)
+{
+	struct grid_line	*gl;
+	u_int			 sy = gd->sy + n;
+
+	gd->linedata = xreallocarray(gd->linedata, sy, sizeof *gd->linedata);
+	gl = &gd->linedata[gd->sy];
+	memset(gl, 0, n * (sizeof *gl));
+	gd->sy = sy;
+	return (gl);
+}
+
+/* Move a line across. */
+static struct grid_line *
+grid_reflow_move(struct grid *gd, struct grid_line *from)
+{
+	struct grid_line	*to;
+
+	to = grid_reflow_add(gd, 1);
+	memcpy(to, from, sizeof *to);
+	grid_reflow_dead(from);
+	return (to);
+}
+
+/* Join line below onto this one. */
+static void
+grid_reflow_join(struct grid *target, struct grid *gd, u_int sx, u_int yy,
+    u_int width, int already)
+{
+	struct grid_line	*gl, *from = NULL;
+	struct grid_cell	 gc;
+	u_int			 lines, left, i, to, line, want = 0;
+	u_int			 at;
+	int			 wrapped = 1;
+
+	/*
+	 * Add a new target line.
+	 */
+	if (!already) {
+		to = target->sy;
+		gl = grid_reflow_move(target, &gd->linedata[yy]);
+	} else {
+		to = target->sy - 1;
+		gl = &target->linedata[to];
+	}
+	at = gl->cellused;
+
+	/*
+	 * Loop until no more to consume or the target line is full.
+	 */
+	lines = 0;
+	for (;;) {
+		/*
+		 * If this is now the last line, there is nothing more to be
+		 * done.
+		 */
+		if (yy + 1 + lines == gd->hsize + gd->sy)
+			break;
+		line = yy + 1 + lines;
+
+		/* If the next line is empty, skip it. */
+		if (~gd->linedata[line].flags & GRID_LINE_WRAPPED)
+			wrapped = 0;
+		if (gd->linedata[line].cellused == 0) {
+			if (!wrapped)
+				break;
+			lines++;
+			continue;
+		}
+
+		/*
+		 * Is the destination line now full? Copy the first character
+		 * separately because we need to leave "from" set to the last
+		 * line if this line is full.
+		 */
+		grid_get_cell1(&gd->linedata[line], 0, &gc);
+		if (width + gc.data.width > sx)
+			break;
+		width += gc.data.width;
+		grid_set_cell(target, at, to, &gc);
+		at++;
+
+		/* Join as much more as possible onto the current line. */
+		from = &gd->linedata[line];
+		for (want = 1; want < from->cellused; want++) {
+			grid_get_cell1(from, want, &gc);
+			if (width + gc.data.width > sx)
+				break;
+			width += gc.data.width;
+
+			grid_set_cell(target, at, to, &gc);
+			at++;
+		}
+		lines++;
+
+		/*
+		 * If this line wasn't wrapped or we didn't consume the entire
+		 * line, don't try to join any further lines.
+		 */
+		if (!wrapped || want != from->cellused || width == sx)
+			break;
+	}
+	if (lines == 0)
+		return;
+
+	/*
+	 * If we didn't consume the entire final line, then remove what we did
+	 * consume. If we consumed the entire line and it wasn't wrapped,
+	 * remove the wrap flag from this line.
+	 */
+	left = from->cellused - want;
+	if (left != 0) {
+		grid_move_cells(gd, 0, want, yy + lines, left, 8);
+		from->cellsize = from->cellused = left;
+		lines--;
+	} else if (!wrapped)
+		gl->flags &= ~GRID_LINE_WRAPPED;
+
+	/* Remove the lines that were completely consumed. */
+	for (i = yy + 1; i < yy + 1 + lines; i++) {
+		free(gd->linedata[i].celldata);
+		free(gd->linedata[i].extddata);
+		grid_reflow_dead(&gd->linedata[i]);
+	}
+
+	/* Adjust scroll position. */
+	if (gd->hscrolled > to + lines)
+		gd->hscrolled -= lines;
+	else if (gd->hscrolled > to)
+		gd->hscrolled = to;
+}
+
+/* Split this line into several new ones */
+static void
+grid_reflow_split(struct grid *target, struct grid *gd, u_int sx, u_int yy,
+    u_int at)
+{
+	struct grid_line	*gl = &gd->linedata[yy], *first;
+	struct grid_cell	 gc;
+	u_int			 line, lines, width, i, xx;
+	u_int			 used = gl->cellused;
+	int			 flags = gl->flags;
+
+	/* How many lines do we need to insert? We know we need at least two. */
+	if (~gl->flags & GRID_LINE_EXTENDED)
+		lines = 1 + (gl->cellused - 1) / sx;
+	else {
+		lines = 2;
+		width = 0;
+		for (i = at; i < used; i++) {
+			grid_get_cell1(gl, i, &gc);
+			if (width + gc.data.width > sx) {
+				lines++;
+				width = 0;
+			}
+			width += gc.data.width;
+		}
+	}
+
+	/* Insert new lines. */
+	line = target->sy + 1;
+	first = grid_reflow_add(target, lines);
+
+	/* Copy sections from the original line. */
+	width = 0;
+	xx = 0;
+	for (i = at; i < used; i++) {
+		grid_get_cell1(gl, i, &gc);
+		if (width + gc.data.width > sx) {
+			target->linedata[line].flags |= GRID_LINE_WRAPPED;
+
+			line++;
+			width = 0;
+			xx = 0;
+		}
+		width += gc.data.width;
+		grid_set_cell(target, xx, line, &gc);
+		xx++;
+	}
+	if (flags & GRID_LINE_WRAPPED)
+		target->linedata[line].flags |= GRID_LINE_WRAPPED;
+
+	/* Move the remainder of the original line. */
+	gl->cellsize = gl->cellused = at;
+	gl->flags |= GRID_LINE_WRAPPED;
+	memcpy(first, gl, sizeof *first);
+	grid_reflow_dead(gl);
+
+	/* Adjust the scroll position. */
+	if (yy <= gd->hscrolled)
+		gd->hscrolled += lines - 1;
+
+	/*
+	 * If the original line had the wrapped flag and there is still space
+	 * in the last new line, try to join with the next lines.
+	 */
+	if (width < sx && (flags & GRID_LINE_WRAPPED))
+		grid_reflow_join(target, gd, sx, yy, width, 1);
+}
+
+/* Reflow lines on grid to new width. */
+void
+grid_reflow(struct grid *gd, u_int sx)
+{
+	struct grid		*target;
+	struct grid_line	*gl;
+	struct grid_cell	 gc;
+	u_int			 yy, width, i, at;
+
+	/*
+	 * Create a destination grid. This is just used as a container for the
+	 * line data and may not be fully valid.
+	 */
+	target = grid_create(gd->sx, 0, 0);
+
+	/*
+	 * Loop over each source line.
+	 */
+	for (yy = 0; yy < gd->hsize + gd->sy; yy++) {
+		gl = &gd->linedata[yy];
+		if (gl->flags & GRID_LINE_DEAD)
+			continue;
+
+		/*
+		 * Work out the width of this line. at is the point at which
+		 * the available width is hit, and width is the full line
+		 * width.
+		 */
+		at = width = 0;
+		if (~gl->flags & GRID_LINE_EXTENDED) {
+			width = gl->cellused;
+			if (width > sx)
+				at = sx;
+			else
+				at = width;
+		} else {
+			for (i = 0; i < gl->cellused; i++) {
+				grid_get_cell1(gl, i, &gc);
+				if (at == 0 && width + gc.data.width > sx)
+					at = i;
+				width += gc.data.width;
+			}
+		}
+
+		/*
+		 * If the line is exactly right, just move it across
+		 * unchanged.
+		 */
+		if (width == sx) {
+			grid_reflow_move(target, gl);
+			continue;
+		}
+
+		/*
+		 * If the line is too big, it needs to be split, whether or not
+		 * it was previously wrapped.
+		 */
+		if (width > sx) {
+			grid_reflow_split(target, gd, sx, yy, at);
+			continue;
+		}
+
+		/*
+		 * If the line was previously wrapped, join as much as possible
+		 * of the next line.
+		 */
+		if (gl->flags & GRID_LINE_WRAPPED)
+			grid_reflow_join(target, gd, sx, yy, width, 0);
+		else
+			grid_reflow_move(target, gl);
+	}
+
+	/*
+	 * Replace the old grid with the new.
+	 */
+	if (target->sy < gd->sy)
+		grid_reflow_add(target, gd->sy - target->sy);
+	gd->hsize = target->sy - gd->sy;
+	if (gd->hscrolled > gd->hsize)
+		gd->hscrolled = gd->hsize;
+	free(gd->linedata);
+	gd->linedata = target->linedata;
+	free(target);
+}
+
+/* Convert to position based on wrapped lines. */
+void
+grid_wrap_position(struct grid *gd, u_int px, u_int py, u_int *wx, u_int *wy)
+{
+	u_int	ax = 0, ay = 0, yy;
+
+	for (yy = 0; yy < py; yy++) {
+		if (gd->linedata[yy].flags & GRID_LINE_WRAPPED)
+			ax += gd->linedata[yy].cellused;
+		else {
+			ax = 0;
+			ay++;
+		}
+	}
+	if (px >= gd->linedata[yy].cellused)
+		ax = UINT_MAX;
+	else
+		ax += px;
+	*wx = ax;
+	*wy = ay;
+}
+
+/* Convert position based on wrapped lines back. */
+void
+grid_unwrap_position(struct grid *gd, u_int *px, u_int *py, u_int wx, u_int wy)
+{
+	u_int	yy, ay = 0;
+
+	for (yy = 0; yy < gd->hsize + gd->sy - 1; yy++) {
+		if (ay == wy)
+			break;
+		if (~gd->linedata[yy].flags & GRID_LINE_WRAPPED)
+			ay++;
+	}
+
+	/*
+	 * yy is now 0 on the unwrapped line which contains wx. Walk forwards
+	 * until we find the end or the line now containing wx.
+	 */
+	if (wx == UINT_MAX) {
+		while (gd->linedata[yy].flags & GRID_LINE_WRAPPED)
+			yy++;
+		wx = gd->linedata[yy].cellused;
+	} else {
+		while (gd->linedata[yy].flags & GRID_LINE_WRAPPED) {
+			if (wx < gd->linedata[yy].cellused)
+				break;
+			wx -= gd->linedata[yy].cellused;
+			yy++;
+		}
+	}
+	*px = wx;
+	*py = yy;
+}
+
+/* Get length of line. */
+u_int
+grid_line_length(struct grid *gd, u_int py)
+{
+	struct grid_cell	gc;
+	u_int			px;
+
+	px = grid_get_line(gd, py)->cellsize;
+	if (px > gd->sx)
+		px = gd->sx;
+	while (px > 0) {
+		grid_get_cell(gd, px - 1, py, &gc);
+		if ((gc.flags & GRID_FLAG_PADDING) ||
+		    gc.data.size != 1 ||
+		    *gc.data.data != ' ')
+			break;
+		px--;
+	}
+	return (px);
+}