Use xfree not free, from Tiago Cunha.

[tmux-openbsd.git] / grid.c

/* $OpenBSD$ */

/*
 * Copyright (c) 2008 Nicholas Marriott <nicm@users.sourceforge.net>
 *
 * 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 <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, 0, 8, 8, ' ' };

#define grid_put_cell(gd, px, py, gc) do {                      \
        memcpy(&gd->linedata[py].celldata[px],                  \
            gc, sizeof gd->linedata[py].celldata[px]);          \
} while (0)
#define grid_put_utf8(gd, px, py, gc) do {                      \
        memcpy(&gd->linedata[py].utf8data[px],                  \
            gc, sizeof gd->linedata[py].utf8data[px]);          \
} while (0)

int     grid_check_y(struct grid *, u_int);

#ifdef DEBUG
int
grid_check_y(struct grid *gd, u_int py)
{
        if ((py) >= (gd)->hsize + (gd)->sy)
                log_fatalx("y out of range: %u", py);
        return (0);
}
#else
int
grid_check_y(struct grid *gd, u_int py)
{
        if ((py) >= (gd)->hsize + (gd)->sy) {
                log_debug("y out of range: %u", py);
                return (-1);
        }
        return (0);
}
#endif

/* 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;

        gd->flags = GRID_HISTORY;

        gd->hsize = 0;
        gd->hlimit = hlimit;

        gd->linedata = xcalloc(gd->sy, sizeof *gd->linedata);

        return (gd);
}

/* Destroy grid. */
void
grid_destroy(struct grid *gd)
{
        struct grid_line        *gl;
        u_int                    yy;

        for (yy = 0; yy < gd->hsize + gd->sy; yy++) {
                gl = &gd->linedata[yy];
                if (gl->celldata != NULL)
                        xfree(gl->celldata);
                if (gl->utf8data != NULL)
                        xfree(gl->utf8data);
        }

        xfree(gd->linedata);

        xfree(gd);
}

/* Compare grids. */
int
grid_compare(struct grid *ga, struct grid *gb)
{
        struct grid_line        *gla, *glb;
        struct grid_cell        *gca, *gcb;
        struct grid_utf8        *gua, *gub;
        u_int                    xx, yy;

        if (ga->sx != gb->sx || ga->sy != ga->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 < ga->sx; xx++) {
                        gca = &gla->celldata[xx];
                        gcb = &glb->celldata[xx];
                        if (memcmp(gca, gcb, sizeof (struct grid_cell)) != 0)
                                return (1);
                        if (!(gca->flags & GRID_FLAG_UTF8))
                                continue;
                        gua = &gla->utf8data[xx];
                        gub = &glb->utf8data[xx];
                        if (memcmp(gua, gub, sizeof (struct grid_utf8)) != 0)
                                return (1);
                }
        }

        return (0);
}

/*
 * 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   yy;

        GRID_DEBUG(gd, "");

        if (gd->hsize < gd->hlimit)
                return;

        yy = gd->hlimit / 10;
        if (yy < 1)
                yy = 1;

        grid_move_lines(gd, 0, yy, gd->hsize + gd->sy - yy);
        gd->hsize -= yy;
}

/*
 * 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   yy;

        GRID_DEBUG(gd, "");

        yy = gd->hsize + gd->sy;
        gd->linedata = xrealloc(gd->linedata, yy + 1, sizeof *gd->linedata);
        memset(&gd->linedata[yy], 0, sizeof gd->linedata[yy]);

        gd->hsize++;
}

/* 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)
{
        struct grid_line        *gl_history, *gl_upper, *gl_lower;
        u_int                    yy;

        GRID_DEBUG(gd, "upper=%u, lower=%u", upper, lower);

        /* Create a space for a new line. */
        yy = gd->hsize + gd->sy;
        gd->linedata = xrealloc(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++;
        gl_lower = &gd->linedata[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);
        memset(gl_lower, 0, sizeof *gl_lower);

        /* Move the history offset down over the line. */
        gd->hsize++;
}

/* Expand line to fit to cell. */
void
grid_expand_line(struct grid *gd, u_int py, u_int sx)
{
        struct grid_line        *gl;
        u_int                    xx;

        gl = &gd->linedata[py];
        if (sx <= gl->cellsize)
                return;

        gl->celldata = xrealloc(gl->celldata, sx, sizeof *gl->celldata);
        for (xx = gl->cellsize; xx < sx; xx++)
                grid_put_cell(gd, xx, py, &grid_default_cell);
        gl->cellsize = sx;
}

/* Expand line to fit to cell for UTF-8. */
void
grid_expand_line_utf8(struct grid *gd, u_int py, u_int sx)
{
        struct grid_line        *gl;

        gl = &gd->linedata[py];
        if (sx <= gl->utf8size)
                return;

        gl->utf8data = xrealloc(gl->utf8data, sx, sizeof *gl->utf8data);
        gl->utf8size = sx;
}

/* Get cell for reading. */
const struct grid_cell *
grid_peek_cell(struct grid *gd, u_int px, u_int py)
{
        if (grid_check_y(gd, py) != 0)
                return (&grid_default_cell);

        if (px >= gd->linedata[py].cellsize)
                return (&grid_default_cell);
        return (&gd->linedata[py].celldata[px]);
}

/* Get cell at relative position (for writing). */
struct grid_cell *
grid_get_cell(struct grid *gd, u_int px, u_int py)
{
        if (grid_check_y(gd, py) != 0)
                return (NULL);

        grid_expand_line(gd, py, px + 1);
        return (&gd->linedata[py].celldata[px]);
}

/* Set cell at relative position. */
void
grid_set_cell(
    struct grid *gd, u_int px, u_int py, const struct grid_cell *gc)
{
        if (grid_check_y(gd, py) != 0)
                return;

        grid_expand_line(gd, py, px + 1);
        grid_put_cell(gd, px, py, gc);
}

/* Get UTF-8 for reading. */
const struct grid_utf8 *
grid_peek_utf8(struct grid *gd, u_int px, u_int py)
{
        if (grid_check_y(gd, py) != 0)
                return (NULL);

        if (px >= gd->linedata[py].utf8size)
                return (NULL);
        return (&gd->linedata[py].utf8data[px]);
}

/* Get utf8 at relative position (for writing). */
struct grid_utf8 *
grid_get_utf8(struct grid *gd, u_int px, u_int py)
{
        if (grid_check_y(gd, py) != 0)
                return (NULL);

        grid_expand_line_utf8(gd, py, px + 1);
        return (&gd->linedata[py].utf8data[px]);
}

/* Set utf8 at relative position. */
void
grid_set_utf8(
    struct grid *gd, u_int px, u_int py, const struct grid_utf8 *gc)
{
        if (grid_check_y(gd, py) != 0)
                return;

        grid_expand_line_utf8(gd, py, px + 1);
        grid_put_utf8(gd, px, py, gc);
}

/* Clear area. */
void
grid_clear(struct grid *gd, u_int px, u_int py, u_int nx, u_int ny)
{
        u_int   xx, yy;

        GRID_DEBUG(gd, "px=%u, py=%u, nx=%u, ny=%u", px, py, nx, ny);

        if (nx == 0 || ny == 0)
                return;

        if (px == 0 && nx == gd->sx) {
                grid_clear_lines(gd, py, ny);
                return;
        }

        if (grid_check_y(gd, py) != 0)
                return;
        if (grid_check_y(gd, py + ny - 1) != 0)
                return;

        for (yy = py; yy < py + ny; yy++) {
                if (px >= gd->linedata[yy].cellsize)
                        continue;
                if (px + nx >= gd->linedata[yy].cellsize) {
                        gd->linedata[yy].cellsize = px;
                        continue;
                }
                for (xx = px; xx < px + nx; xx++) {
                        if (xx >= gd->linedata[yy].cellsize)
                                break;
                        grid_put_cell(gd, xx, yy, &grid_default_cell);
                }
        }
}

/* Clear lines. This just frees and truncates the lines. */
void
grid_clear_lines(struct grid *gd, u_int py, u_int ny)
{
        struct grid_line        *gl;
        u_int                    yy;

        GRID_DEBUG(gd, "py=%u, ny=%u", py, ny);

        if (ny == 0)
                return;

        if (grid_check_y(gd, py) != 0)
                return;
        if (grid_check_y(gd, py + ny - 1) != 0)
                return;

        for (yy = py; yy < py + ny; yy++) {
                gl = &gd->linedata[yy];
                if (gl->celldata != NULL)
                        xfree(gl->celldata);
                if (gl->utf8data != NULL)
                        xfree(gl->utf8data);
                memset(gl, 0, sizeof *gl);
        }
}

/* Move a group of lines. */
void
grid_move_lines(struct grid *gd, u_int dy, u_int py, u_int ny)
{
        u_int   yy;

        GRID_DEBUG(gd, "dy=%u, py=%u, ny=%u", dy, py, ny);

        if (ny == 0 || py == dy)
                return;

        if (grid_check_y(gd, py) != 0)
                return;
        if (grid_check_y(gd, py + ny - 1) != 0)
                return;
        if (grid_check_y(gd, dy) != 0)
                return;
        if (grid_check_y(gd, 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_clear_lines(gd, yy, 1);
        }

        memmove(
            &gd->linedata[dy], &gd->linedata[py], ny * (sizeof *gd->linedata));

        /* Wipe any lines that have been moved (without freeing them). */
        for (yy = py; yy < py + ny; yy++) {
                if (yy >= dy && yy < dy + ny)
                        continue;
                memset(&gd->linedata[yy], 0, sizeof gd->linedata[yy]);
        }
}

/* Move a group of cells. */
void
grid_move_cells(struct grid *gd, u_int dx, u_int px, u_int py, u_int nx)
{
        struct grid_line        *gl;
        u_int                    xx;

        GRID_DEBUG(gd, "dx=%u, px=%u, py=%u, nx=%u", dx, px, py, nx);

        if (nx == 0 || px == dx)
                return;

        if (grid_check_y(gd, py) != 0)
                return;
        gl = &gd->linedata[py];

        grid_expand_line(gd, py, px + nx);
        grid_expand_line(gd, py, dx + nx);
        memmove(
            &gl->celldata[dx], &gl->celldata[px], nx * sizeof *gl->celldata);

        if (gl->utf8data != NULL) {
                grid_expand_line_utf8(gd, py, px + nx);
                grid_expand_line_utf8(gd, py, dx + nx);
                memmove(&gl->utf8data[dx],
                    &gl->utf8data[px], nx * sizeof *gl->utf8data);
        }

        /* Wipe any cells that have been moved. */
        for (xx = px; xx < px + nx; xx++) {
                if (xx >= dx && xx < dx + nx)
                        continue;
                grid_put_cell(gd, xx, py, &grid_default_cell);
        }
}

/* Convert cells into a string. */
char *
grid_string_cells(struct grid *gd, u_int px, u_int py, u_int nx)
{
        const struct grid_cell  *gc;
        const struct grid_utf8  *gu;
        char                    *buf;
        size_t                   len, off, size;
        u_int                    xx;

        GRID_DEBUG(gd, "px=%u, py=%u, nx=%u", px, py, nx);

        len = 128;
        buf = xmalloc(len);
        off = 0;

        for (xx = px; xx < px + nx; xx++) {
                gc = grid_peek_cell(gd, xx, py);
                if (gc->flags & GRID_FLAG_PADDING)
                        continue;

                if (gc->flags & GRID_FLAG_UTF8) {
                        gu = grid_peek_utf8(gd, xx, py);

                        size = grid_utf8_size(gu);
                        while (len < off + size + 1) {
                                buf = xrealloc(buf, 2, len);
                                len *= 2;
                        }

                        off += grid_utf8_copy(gu, buf + off, len - off);
                } else {
                        while (len < off + 2) {
                                buf = xrealloc(buf, 2, len);
                                len *= 2;
                        }

                        buf[off++] = gc->data;
                }
        }

        while (off > 0 && buf[off - 1] == ' ')
                off--;
        buf[off] = '\0';
        return (buf);
}

/*
 * Duplicate a set of lines between two grids. If there aren't enough lines in
 * either source or destination, the number of lines is limited to the number
 * available.
 */
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;

        GRID_DEBUG(src, "dy=%u, sy=%u, ny=%u", dy, sy, ny);

        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_clear_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 = xcalloc(
                            srcl->cellsize, sizeof *dstl->celldata);
                        memcpy(dstl->celldata, srcl->celldata,
                            srcl->cellsize * sizeof *dstl->celldata);
                }
                if (srcl->utf8size != 0) {
                        dstl->utf8data = xcalloc(
                            srcl->utf8size, sizeof *dstl->utf8data);
                        memcpy(dstl->utf8data, srcl->utf8data,
                            srcl->utf8size * sizeof *dstl->utf8data);
                }

                sy++;
                dy++;
        }
}