Handle no client better in display-message.

[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 <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, 0, 8, 8, (1 << 4) | 1, " " };
const struct grid_cell grid_marker_cell = { 0, 0, 8, 8, (1 << 4) | 1, "_" };

#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

void    grid_reflow_join(struct grid *, u_int *, struct grid_line *, u_int);
void    grid_reflow_split(struct grid *, u_int *, struct grid_line *, u_int,
            u_int);
void    grid_reflow_move(struct grid *, u_int *, struct grid_line *);
size_t  grid_string_cells_fg(const struct grid_cell *, int *);
size_t  grid_string_cells_bg(const struct grid_cell *, int *);
void    grid_string_cells_code(const struct grid_cell *,
            const struct grid_cell *, char *, size_t, int);

/* 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];
                free(gl->celldata);
        }

        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 != 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);
                }
        }

        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;
}

/* Peek at grid line. */
const struct grid_line *
grid_peek_line(struct grid *gd, u_int py)
{
        if (grid_check_y(gd, py) != 0)
                return (NULL);
        return (&gd->linedata[py]);
}

/* 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);
}

/* 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];
                free(gl->celldata);
                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);

        /* 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);
        }
}

/* Get ANSI foreground sequence. */
size_t
grid_string_cells_fg(const struct grid_cell *gc, int *values)
{
        size_t  n;

        n = 0;
        if (gc->flags & GRID_FLAG_FG256) {
                values[n++] = 38;
                values[n++] = 5;
                values[n++] = gc->fg;
        } 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. */
size_t
grid_string_cells_bg(const struct grid_cell *gc, int *values)
{
        size_t  n;

        n = 0;
        if (gc->flags & GRID_FLAG_BG256) {
                values[n++] = 48;
                values[n++] = 5;
                values[n++] = gc->bg;
        } 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 100:
                case 101:
                case 102:
                case 103:
                case 104:
                        case 105:
                case 106:
                case 107:
                        values[n++] = gc->bg - 10;
                        break;
                }
        }
        return (n);
}

/*
 * Returns ANSI code to set particular attributes (colour, bold and so on)
 * given a current state. The output buffer must be able to hold at least 57
 * bytes.
 */
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[16], newc[16], s[32];
        size_t  noldc, nnewc, n, i;
        u_int   attr = gc->attr;
        u_int   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 }
        };
        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)) {
                        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;
        }

        /* If the foreground c changed, append its parameters. */
        nnewc = grid_string_cells_fg(gc, newc);
        noldc = grid_string_cells_fg(lastgc, oldc);
        if (nnewc != noldc ||
            memcmp(newc,oldc, nnewc * sizeof newc[0]) != 0) {
                for (i = 0; i < nnewc; i++)
                        s[n++] = newc[i];
        }

        /* If the background c changed, append its parameters. */
        nnewc = grid_string_cells_bg(gc, newc);
        noldc = grid_string_cells_bg(lastgc, oldc);
        if (nnewc != noldc ||
            memcmp(newc, oldc, nnewc * sizeof newc[0]) != 0) {
                for (i = 0; i < nnewc; i++)
                        s[n++] = newc[i];
        }

        /* If there are any parameters, append an SGR code. */
        *buf = '\0';
        if (n > 0) {
                if (escape_c0)
                        strlcat(buf, "\\033[", len);
                else
                        strlcat(buf, "\033[", len);
                for (i = 0; i < n; i++) {
                        if (i + 1 < n)
                                xsnprintf(tmp, sizeof tmp, "%d;", s[i]);
                        else
                                xsnprintf(tmp, sizeof tmp, "%d", s[i]);
                        strlcat(buf, tmp, len);
                }
                strlcat(buf, "m", len);
        }

        /* 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)
{
        const struct grid_cell  *gc;
        static struct grid_cell  lastgc1;
        struct utf8_data         ud;
        const char*              data;
        char                    *buf, code[128];
        size_t                   len, off, size, codelen;
        u_int                    xx;

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

        if (lastgc != NULL && *lastgc == NULL) {
                memcpy(&lastgc1, &grid_default_cell, sizeof lastgc1);
                *lastgc = &lastgc1;
        }

        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;
                grid_cell_get(gc, &ud);

                if (with_codes) {
                        grid_string_cells_code(*lastgc, gc, code, sizeof code,
                            escape_c0);
                        codelen = strlen(code);
                        memcpy(*lastgc, gc, sizeof *gc);
                } else
                        codelen = 0;

                data = ud.data;
                size = ud.size;
                if (escape_c0 && size == 1 && *data == '\\') {
                        data = "\\\\";
                        size = 2;
                }

                while (len < off + size + codelen + 1) {
                        buf = xrealloc(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. 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);
                }

                sy++;
                dy++;
        }
}

/* Join line data. */
void
grid_reflow_join(struct grid *dst, u_int *py, struct grid_line *src_gl,
    u_int new_x)
{
        struct grid_line        *dst_gl = &dst->linedata[(*py) - 1];
        u_int                    left, to_copy, ox, nx;

        /* How much is left on the old line? */
        left = new_x - dst_gl->cellsize;

        /* Work out how much to append. */
        to_copy = src_gl->cellsize;
        if (to_copy > left)
                to_copy = left;
        ox = dst_gl->cellsize;
        nx = ox + to_copy;

        /* Resize the destination line. */
        dst_gl->celldata = xrealloc(dst_gl->celldata, nx,
            sizeof *dst_gl->celldata);
        dst_gl->cellsize = nx;

        /* Append as much as possible. */
        memcpy(&dst_gl->celldata[ox], &src_gl->celldata[0],
            to_copy * sizeof src_gl->celldata[0]);

        /* If there is any left in the source, split it. */
        if (src_gl->cellsize > to_copy) {
                dst_gl->flags |= GRID_LINE_WRAPPED;

                src_gl->cellsize -= to_copy;
                grid_reflow_split(dst, py, src_gl, new_x, to_copy);
        }
}

/* Split line data. */
void
grid_reflow_split(struct grid *dst, u_int *py, struct grid_line *src_gl,
    u_int new_x, u_int offset)
{
        struct grid_line        *dst_gl = NULL;
        u_int                    to_copy;

        /* Loop and copy sections of the source line. */
        while (src_gl->cellsize > 0) {
                /* Create new line. */
                if (*py >= dst->hsize + dst->sy)
                        grid_scroll_history(dst);
                dst_gl = &dst->linedata[*py];
                (*py)++;

                /* How much should we copy? */
                to_copy = new_x;
                if (to_copy > src_gl->cellsize)
                        to_copy = src_gl->cellsize;

                /* Expand destination line. */
                dst_gl->celldata = xmalloc(to_copy * sizeof *dst_gl->celldata);
                dst_gl->cellsize = to_copy;
                dst_gl->flags |= GRID_LINE_WRAPPED;

                /* Copy the data. */
                memcpy (&dst_gl->celldata[0], &src_gl->celldata[offset],
                    to_copy * sizeof dst_gl->celldata[0]);

                /* Move offset and reduce old line size. */
                offset += to_copy;
                src_gl->cellsize -= to_copy;
        }

        /* Last line is not wrapped. */
        if (dst_gl != NULL)
                dst_gl->flags &= ~GRID_LINE_WRAPPED;
}

/* Move line data. */
void
grid_reflow_move(struct grid *dst, u_int *py, struct grid_line *src_gl)
{
        struct grid_line        *dst_gl;

        /* Create new line. */
        if (*py >= dst->hsize + dst->sy)
                grid_scroll_history(dst);
        dst_gl = &dst->linedata[*py];
        (*py)++;

        /* Copy the old line. */
        memcpy(dst_gl, src_gl, sizeof *dst_gl);
        dst_gl->flags &= ~GRID_LINE_WRAPPED;

        /* Clear old line. */
        src_gl->celldata = NULL;
}

/*
 * Reflow lines from src grid into dst grid of width new_x. Returns number of
 * lines fewer in the visible area. The source grid is destroyed.
 */
u_int
grid_reflow(struct grid *dst, struct grid *src, u_int new_x)
{
        u_int                    py, sy, line;
        int                      previous_wrapped;
        struct grid_line        *src_gl;

        py = 0;
        sy = src->sy;

        previous_wrapped = 0;
        for (line = 0; line < sy + src->hsize; line++) {
                src_gl = src->linedata + line;
                if (!previous_wrapped) {
                        /* Wasn't wrapped. If smaller, move to destination. */
                        if (src_gl->cellsize <= new_x)
                                grid_reflow_move(dst, &py, src_gl);
                        else
                                grid_reflow_split(dst, &py, src_gl, new_x, 0);
                } else {
                        /* Previous was wrapped. Try to join. */
                        grid_reflow_join(dst, &py, src_gl, new_x);
                }
                previous_wrapped = src_gl->flags & GRID_LINE_WRAPPED;
        }

        grid_destroy(src);

        if (py > sy)
                return (0);
        return (sy - py);
}