foot/wayland.c

#include "wayland.h"

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

#include <sys/timerfd.h>
#include <sys/epoll.h>

#include <wayland-client.h>
#include <wayland-cursor.h>
#include <xdg-shell.h>
#include <xkbcommon/xkbcommon-compose.h>

#include <xdg-output-unstable-v1.h>
#include <xdg-decoration-unstable-v1.h>

#define LOG_MODULE "wayland"
#define LOG_ENABLE_DBG 0
#include "log.h"

#include "tllist.h"
#include "terminal.h"
#include "input.h"
#include "render.h"
#include "selection.h"

#define min(x, y) ((x) < (y) ? (x) : (y))
#define max(x, y) ((x) > (y) ? (x) : (y))

static void
shm_format(void *data, struct wl_shm *wl_shm, uint32_t format)
{
    struct wayland *wayl = data;
    if (format == WL_SHM_FORMAT_ARGB8888)
        wayl->have_argb8888 = true;
}

static const struct wl_shm_listener shm_listener = {
    .format = &shm_format,
};

static void
xdg_wm_base_ping(void *data, struct xdg_wm_base *shell, uint32_t serial)
{
    LOG_DBG("wm base ping");
    xdg_wm_base_pong(shell, serial);
}

static const struct xdg_wm_base_listener xdg_wm_base_listener = {
    .ping = &xdg_wm_base_ping,
};

static void
seat_handle_capabilities(void *data, struct wl_seat *wl_seat,
                         enum wl_seat_capability caps)
{
    struct wayland *wayl = data;

    if (wayl->keyboard != NULL) {
        wl_keyboard_release(wayl->keyboard);
        wayl->keyboard = NULL;
    }

    if (wayl->pointer.pointer != NULL) {
        wl_pointer_release(wayl->pointer.pointer);
        wayl->pointer.pointer = NULL;
    }

    if (caps & WL_SEAT_CAPABILITY_KEYBOARD) {
        wayl->keyboard = wl_seat_get_keyboard(wl_seat);
        wl_keyboard_add_listener(wayl->keyboard, &keyboard_listener, wayl);
    }

    if (caps & WL_SEAT_CAPABILITY_POINTER) {
        wayl->pointer.pointer = wl_seat_get_pointer(wl_seat);
        wl_pointer_add_listener(wayl->pointer.pointer, &pointer_listener, wayl);
    }
}

static void
seat_handle_name(void *data, struct wl_seat *wl_seat, const char *name)
{
}

static const struct wl_seat_listener seat_listener = {
    .capabilities = seat_handle_capabilities,
    .name = seat_handle_name,
};

static void
output_geometry(void *data, struct wl_output *wl_output, int32_t x, int32_t y,
                int32_t physical_width, int32_t physical_height,
                int32_t subpixel, const char *make, const char *model,
                int32_t transform)
{
    struct monitor *mon = data;
    mon->width_mm = physical_width;
    mon->height_mm = physical_height;
}

static void
output_mode(void *data, struct wl_output *wl_output, uint32_t flags,
            int32_t width, int32_t height, int32_t refresh)
{
    if ((flags & WL_OUTPUT_MODE_CURRENT) == 0)
        return;

    struct monitor *mon = data;
    mon->refresh = (float)refresh / 1000;
}

static void
output_done(void *data, struct wl_output *wl_output)
{
}

static void
output_scale(void *data, struct wl_output *wl_output, int32_t factor)
{
    struct monitor *mon = data;

    mon->scale = factor;

    struct terminal *term = mon->wayl->term;
    if (term != NULL) {
        render_resize(term, term->width / term->scale, term->height / term->scale);
        render_reload_cursor_theme(term);
    }
}

static const struct wl_output_listener output_listener = {
    .geometry = &output_geometry,
    .mode = &output_mode,
    .done = &output_done,
    .scale = &output_scale,
};

static void
xdg_output_handle_logical_position(
    void *data, struct zxdg_output_v1 *xdg_output, int32_t x, int32_t y)
{
    struct monitor *mon = data;
    mon->x = x;
    mon->y = y;
}

static void
xdg_output_handle_logical_size(void *data, struct zxdg_output_v1 *xdg_output,
                               int32_t width, int32_t height)
{
    struct monitor *mon = data;
    mon->width_px = width;
    mon->height_px = height;
}

static void
xdg_output_handle_done(void *data, struct zxdg_output_v1 *xdg_output)
{
}

static void
xdg_output_handle_name(void *data, struct zxdg_output_v1 *xdg_output,
                       const char *name)
{
    struct monitor *mon = data;
    mon->name = strdup(name);
}

static void
xdg_output_handle_description(void *data, struct zxdg_output_v1 *xdg_output,
                              const char *description)
{
}

static struct zxdg_output_v1_listener xdg_output_listener = {
    .logical_position = xdg_output_handle_logical_position,
    .logical_size = xdg_output_handle_logical_size,
    .done = xdg_output_handle_done,
    .name = xdg_output_handle_name,
    .description = xdg_output_handle_description,
};

static void
handle_global(void *data, struct wl_registry *registry,
              uint32_t name, const char *interface, uint32_t version)
{
    LOG_DBG("global: %s, version=%u", interface, version);
    struct wayland *wayl = data;

    if (strcmp(interface, wl_compositor_interface.name) == 0) {
        wayl->compositor = wl_registry_bind(
            wayl->registry, name, &wl_compositor_interface, 4);
    }

    else if (strcmp(interface, wl_subcompositor_interface.name) == 0) {
        wayl->sub_compositor = wl_registry_bind(
            wayl->registry, name, &wl_subcompositor_interface, 1);
    }

    else if (strcmp(interface, wl_shm_interface.name) == 0) {
        wayl->shm = wl_registry_bind(
            wayl->registry, name, &wl_shm_interface, 1);
        wl_shm_add_listener(wayl->shm, &shm_listener, wayl);
        wl_display_roundtrip(wayl->display);
    }

    else if (strcmp(interface, xdg_wm_base_interface.name) == 0) {
        wayl->shell = wl_registry_bind(
            wayl->registry, name, &xdg_wm_base_interface, 1);
        xdg_wm_base_add_listener(wayl->shell, &xdg_wm_base_listener, wayl);
    }

    else if (strcmp(interface, zxdg_decoration_manager_v1_interface.name) == 0)
        wayl->xdg_decoration_manager = wl_registry_bind(
            wayl->registry, name, &zxdg_decoration_manager_v1_interface, 1);

    else if (strcmp(interface, wl_seat_interface.name) == 0) {
        wayl->seat = wl_registry_bind(
            wayl->registry, name, &wl_seat_interface, 5);
        wl_seat_add_listener(wayl->seat, &seat_listener, wayl);
        wl_display_roundtrip(wayl->display);
    }

    else if (strcmp(interface, zxdg_output_manager_v1_interface.name) == 0) {
        wayl->xdg_output_manager = wl_registry_bind(
            wayl->registry, name, &zxdg_output_manager_v1_interface, min(version, 2));
    }

    else if (strcmp(interface, wl_output_interface.name) == 0) {
        struct wl_output *output = wl_registry_bind(
            wayl->registry, name, &wl_output_interface, 3);

        tll_push_back(
            wayl->monitors, ((struct monitor){.wayl = wayl, .output = output}));

        struct monitor *mon = &tll_back(wayl->monitors);
        wl_output_add_listener(output, &output_listener, mon);

        mon->xdg = zxdg_output_manager_v1_get_xdg_output(
            wayl->xdg_output_manager, mon->output);
        zxdg_output_v1_add_listener(mon->xdg, &xdg_output_listener, mon);
        wl_display_roundtrip(wayl->display);
    }

    else if (strcmp(interface, wl_data_device_manager_interface.name) == 0) {
        wayl->data_device_manager = wl_registry_bind(
            wayl->registry, name, &wl_data_device_manager_interface, 1);
    }

    else if (strcmp(interface, zwp_primary_selection_device_manager_v1_interface.name) == 0) {
        wayl->primary_selection_device_manager = wl_registry_bind(
            wayl->registry, name, &zwp_primary_selection_device_manager_v1_interface, 1);
    }
}

static void
surface_enter(void *data, struct wl_surface *wl_surface,
              struct wl_output *wl_output)
{
    struct wayland *wayl = data;
    struct terminal *term = wayl_terminal_from_surface(wayl, wl_surface);

    tll_foreach(wayl->monitors, it) {
        if (it->item.output == wl_output) {
            LOG_DBG("mapped on %s", it->item.name);
            tll_push_back(term->window->on_outputs, &it->item);

            /* Resize, since scale-to-use may have changed */
            render_resize(term, term->width / term->scale, term->height / term->scale);
            render_reload_cursor_theme(term);
            return;
        }
    }

    LOG_ERR("mapped on unknown output");
}

static void
surface_leave(void *data, struct wl_surface *wl_surface,
              struct wl_output *wl_output)
{
    struct wayland *wayl = data;
    struct terminal *term = wayl_terminal_from_surface(wayl, wl_surface);

    tll_foreach(term->window->on_outputs, it) {
        if (it->item->output != wl_output)
            continue;

        LOG_DBG("unmapped from %s", it->item->name);
        tll_remove(term->window->on_outputs, it);

        /* Resize, since scale-to-use may have changed */
        render_resize(term, term->width / term->scale, term->height / term->scale);
        render_reload_cursor_theme(term);
        return;
    }

    LOG_ERR("unmapped from unknown output");
}

static const struct wl_surface_listener surface_listener = {
    .enter = &surface_enter,
    .leave = &surface_leave,
};

static void
xdg_toplevel_configure(void *data, struct xdg_toplevel *xdg_toplevel,
                       int32_t width, int32_t height, struct wl_array *states)
{
    LOG_DBG("xdg-toplevel: configure: %dx%d", width, height);

    if (width <= 0 || height <= 0)
        return;

    struct wayland *wayl = data;
    struct terminal *term = wayl_terminal_from_xdg_toplevel(wayl, xdg_toplevel);
    render_resize(term, width, height);
}

static void
xdg_toplevel_close(void *data, struct xdg_toplevel *xdg_toplevel)
{
    struct wayland *wayl = data;
    struct terminal *term = wayl_terminal_from_xdg_toplevel(wayl, xdg_toplevel);
    LOG_DBG("xdg-toplevel: close");

    term->quit = true;
    wl_display_roundtrip(wayl->display);
}

static const struct xdg_toplevel_listener xdg_toplevel_listener = {
    .configure = &xdg_toplevel_configure,
    .close = &xdg_toplevel_close,
};

static void
xdg_surface_configure(void *data, struct xdg_surface *xdg_surface,
                      uint32_t serial)
{
    //LOG_DBG("xdg-surface: configure");
    xdg_surface_ack_configure(xdg_surface, serial);
}

static const struct xdg_surface_listener xdg_surface_listener = {
    .configure = &xdg_surface_configure,
};

static void
xdg_toplevel_decoration_configure(void *data,
                                  struct zxdg_toplevel_decoration_v1 *zxdg_toplevel_decoration_v1,
                                  uint32_t mode)
{
    switch (mode) {
    case ZXDG_TOPLEVEL_DECORATION_V1_MODE_CLIENT_SIDE:
        LOG_ERR("unimplemented: client-side decorations");
        break;

    case ZXDG_TOPLEVEL_DECORATION_V1_MODE_SERVER_SIDE:
        LOG_DBG("using server-side decorations");
        break;

    default:
        LOG_ERR("unimplemented: unknown XDG toplevel decoration mode: %u", mode);
        break;
    }
}

static const struct zxdg_toplevel_decoration_v1_listener xdg_toplevel_decoration_listener = {
    .configure = &xdg_toplevel_decoration_configure,
};

static void
handle_global_remove(void *data, struct wl_registry *registry, uint32_t name)
{
    LOG_WARN("global removed: %u", name);
    assert(false);
}

static const struct wl_registry_listener registry_listener = {
    .global = &handle_global,
    .global_remove = &handle_global_remove,
};

static bool
fdm_wayl(struct fdm *fdm, int fd, int events, void *data)
{
    struct wayland *wayl = data;
    int event_count = wl_display_dispatch(wayl->display);

    if (events & EPOLLHUP) {
        LOG_ERR("disconnected from Wayland");
        return false;
    }

    return event_count != -1 && !wayl->term->quit;
}

static bool
fdm_repeat(struct fdm *fdm, int fd, int events, void *data)
{
    if (events & EPOLLHUP)
        return false;

    struct wayland *wayl = data;
    uint64_t expiration_count;
    ssize_t ret = read(
        wayl->kbd.repeat.fd, &expiration_count, sizeof(expiration_count));

    if (ret < 0) {
        if (errno == EAGAIN)
            return true;

        LOG_ERRNO("failed to read repeat key from repeat timer fd");
        return false;
    }

    wayl->kbd.repeat.dont_re_repeat = true;
    for (size_t i = 0; i < expiration_count; i++)
        input_repeat(wayl, wayl->kbd.repeat.key);
    wayl->kbd.repeat.dont_re_repeat = false;
    return true;
}

struct wayland *
wayl_init(struct fdm *fdm)
{
    struct wayland *wayl = calloc(1, sizeof(*wayl));
    wayl->fdm = fdm;

    wayl->display = wl_display_connect(NULL);
    if (wayl->display == NULL) {
        LOG_ERR("failed to connect to wayland; no compositor running?");
        goto out;
    }

    wayl->registry = wl_display_get_registry(wayl->display);
    if (wayl->registry == NULL) {
        LOG_ERR("failed to get wayland registry");
        goto out;
    }

    wl_registry_add_listener(wayl->registry, &registry_listener, wayl);
    wl_display_roundtrip(wayl->display);

    if (wayl->compositor == NULL) {
        LOG_ERR("no compositor");
        goto out;
    }
    if (wayl->shm == NULL) {
        LOG_ERR("no shared memory buffers interface");
        goto out;
    }
    if (wayl->shell == NULL) {
        LOG_ERR("no XDG shell interface");
        goto out;
    }
    if (!wayl->have_argb8888) {
        LOG_ERR("compositor does not support ARGB surfaces");
        goto out;
    }
    if (wayl->seat == NULL) {
        LOG_ERR("no seat available");
        goto out;
    }
    if (wayl->data_device_manager == NULL) {
        LOG_ERR("no clipboard available "
                "(wl_data_device_manager not implemented by server)");
        goto out;
    }
    if (wayl->primary_selection_device_manager == NULL)
        LOG_WARN("no primary selection available");

    tll_foreach(wayl->monitors, it) {
        LOG_INFO("%s: %dx%d+%dx%d (scale=%d, refresh=%.2fHz)",
                 it->item.name, it->item.width_px, it->item.height_px,
                 it->item.x, it->item.y, it->item.scale, it->item.refresh);
    }

    /* Clipboard */
    wayl->data_device = wl_data_device_manager_get_data_device(
        wayl->data_device_manager, wayl->seat);
    wl_data_device_add_listener(wayl->data_device, &data_device_listener, wayl);

    /* Primary selection */
    if (wayl->primary_selection_device_manager != NULL) {
        wayl->primary_selection_device = zwp_primary_selection_device_manager_v1_get_device(
            wayl->primary_selection_device_manager, wayl->seat);
        zwp_primary_selection_device_v1_add_listener(
            wayl->primary_selection_device, &primary_selection_device_listener, wayl);
    }

    /* Cursor */
    unsigned cursor_size = 24;
    const char *cursor_theme = getenv("XCURSOR_THEME");

    {
        const char *env_cursor_size = getenv("XCURSOR_SIZE");
        if (env_cursor_size != NULL) {
            unsigned size;
            if (sscanf(env_cursor_size, "%u", &size) == 1)
                cursor_size = size;
        }
    }

    /* Note: theme is (re)loaded on scale and output changes */
    LOG_INFO("cursor theme: %s, size: %u", cursor_theme, cursor_size);
    wayl->pointer.size = cursor_size;
    wayl->pointer.theme_name = cursor_theme != NULL ? strdup(cursor_theme) : NULL;

    wayl->pointer.surface = wl_compositor_create_surface(wayl->compositor);
    if (wayl->pointer.surface == NULL) {
        LOG_ERR("failed to create cursor surface");
        goto out;
    }

    wayl->kbd.repeat.fd = timerfd_create(CLOCK_BOOTTIME, TFD_CLOEXEC | TFD_NONBLOCK);
    if (wayl->kbd.repeat.fd == -1) {
        LOG_ERRNO("failed to create keyboard repeat timer FD");
        goto out;
    }

    if (!fdm_add(fdm, wl_display_get_fd(wayl->display), EPOLLIN, &fdm_wayl, wayl)) {
        LOG_ERR("failed to register Wayland connection with the FDM");
        goto out;
    }

    if (!fdm_add(fdm, wayl->kbd.repeat.fd, EPOLLIN, &fdm_repeat, wayl)) {
        LOG_ERR("failed to register keyboard repeat timer with the FDM");
        goto out;
    }

    return wayl;

out:
    if (wayl != NULL)
        wayl_destroy(wayl);
    return NULL;
}

void
wayl_destroy(struct wayland *wayl)
{
    if (wayl == NULL)
        return;

    if (wayl->kbd.repeat.fd != 0) {
        fdm_del(wayl->fdm, wayl->kbd.repeat.fd);
        close(wayl->kbd.repeat.fd);
    }

    tll_foreach(wayl->monitors, it) {
        free(it->item.name);
        if (it->item.xdg != NULL)
            zxdg_output_v1_destroy(it->item.xdg);
        if (it->item.output != NULL)
            wl_output_destroy(it->item.output);
        tll_remove(wayl->monitors, it);
    }

    if (wayl->xdg_output_manager != NULL)
        zxdg_output_manager_v1_destroy(wayl->xdg_output_manager);
    if (wayl->shell != NULL)
        xdg_wm_base_destroy(wayl->shell);

    if (wayl->xdg_decoration_manager != NULL)
        zxdg_decoration_manager_v1_destroy(wayl->xdg_decoration_manager);

    if (wayl->kbd.xkb_compose_state != NULL)
        xkb_compose_state_unref(wayl->kbd.xkb_compose_state);
    if (wayl->kbd.xkb_compose_table != NULL)
        xkb_compose_table_unref(wayl->kbd.xkb_compose_table);
    if (wayl->kbd.xkb_keymap != NULL)
        xkb_keymap_unref(wayl->kbd.xkb_keymap);
    if (wayl->kbd.xkb_state != NULL)
        xkb_state_unref(wayl->kbd.xkb_state);
    if (wayl->kbd.xkb != NULL)
        xkb_context_unref(wayl->kbd.xkb);

    if (wayl->clipboard.data_source != NULL)
        wl_data_source_destroy(wayl->clipboard.data_source);
    if (wayl->clipboard.data_offer != NULL)
        wl_data_offer_destroy(wayl->clipboard.data_offer);
    free(wayl->clipboard.text);
    if (wayl->primary.data_source != NULL)
        zwp_primary_selection_source_v1_destroy(wayl->primary.data_source);
    if (wayl->primary.data_offer != NULL)
        zwp_primary_selection_offer_v1_destroy(wayl->primary.data_offer);
    free(wayl->primary.text);

    free(wayl->pointer.theme_name);
    if (wayl->pointer.theme != NULL)
        wl_cursor_theme_destroy(wayl->pointer.theme);
    if (wayl->pointer.pointer != NULL)
        wl_pointer_destroy(wayl->pointer.pointer);
    if (wayl->pointer.surface != NULL)
        wl_surface_destroy(wayl->pointer.surface);
    if (wayl->keyboard != NULL)
        wl_keyboard_destroy(wayl->keyboard);
    if (wayl->data_device != NULL)
        wl_data_device_destroy(wayl->data_device);
    if (wayl->data_device_manager != NULL)
        wl_data_device_manager_destroy(wayl->data_device_manager);
    if (wayl->primary_selection_device != NULL)
        zwp_primary_selection_device_v1_destroy(wayl->primary_selection_device);
    if (wayl->primary_selection_device_manager != NULL)
        zwp_primary_selection_device_manager_v1_destroy(wayl->primary_selection_device_manager);
    if (wayl->seat != NULL)
        wl_seat_destroy(wayl->seat);
    if (wayl->shm != NULL)
        wl_shm_destroy(wayl->shm);
    if (wayl->sub_compositor != NULL)
        wl_subcompositor_destroy(wayl->sub_compositor);
    if (wayl->compositor != NULL)
        wl_compositor_destroy(wayl->compositor);
    if (wayl->registry != NULL)
        wl_registry_destroy(wayl->registry);
    if (wayl->display != NULL) {
        fdm_del(wayl->fdm, wl_display_get_fd(wayl->display));
        wl_display_disconnect(wayl->display);
    }

    free(wayl);
}

struct wl_window *
wayl_win_init(struct wayland *wayl)
{
    struct wl_window *win = calloc(1, sizeof(*win));

    win->surface = wl_compositor_create_surface(wayl->compositor);
    if (win->surface == NULL) {
        LOG_ERR("failed to create wayland surface");
        goto out;
    }

    wl_surface_add_listener(win->surface, &surface_listener, wayl);

    win->xdg_surface = xdg_wm_base_get_xdg_surface(wayl->shell, win->surface);
    xdg_surface_add_listener(win->xdg_surface, &xdg_surface_listener, wayl);

    win->xdg_toplevel = xdg_surface_get_toplevel(win->xdg_surface);
    xdg_toplevel_add_listener(win->xdg_toplevel, &xdg_toplevel_listener, wayl);

    xdg_toplevel_set_app_id(win->xdg_toplevel, "foot");

    /* Request server-side decorations */
    win->xdg_toplevel_decoration = zxdg_decoration_manager_v1_get_toplevel_decoration(
        wayl->xdg_decoration_manager, win->xdg_toplevel);
    zxdg_toplevel_decoration_v1_set_mode(
        win->xdg_toplevel_decoration, ZXDG_TOPLEVEL_DECORATION_V1_MODE_SERVER_SIDE);
    zxdg_toplevel_decoration_v1_add_listener(
        win->xdg_toplevel_decoration, &xdg_toplevel_decoration_listener, wayl);

    /* Scrollback search box */
    win->search_surface = wl_compositor_create_surface(wayl->compositor);
    win->search_sub_surface = wl_subcompositor_get_subsurface(
        wayl->sub_compositor, win->search_surface, win->surface);
    wl_subsurface_set_desync(win->search_sub_surface);

    wl_surface_commit(win->surface);
    wl_display_roundtrip(wayl->display);

    return win;

out:
    if (win != NULL)
        wayl_win_destroy(win);
    return NULL;
}

void
wayl_win_destroy(struct wl_window *win)
{
    tll_free(win->on_outputs);
    if (win->search_sub_surface != NULL)
        wl_subsurface_destroy(win->search_sub_surface);
    if (win->search_surface != NULL)
        wl_surface_destroy(win->search_surface);
    if (win->frame_callback != NULL)
        wl_callback_destroy(win->frame_callback);
    if (win->xdg_toplevel_decoration != NULL)
        zxdg_toplevel_decoration_v1_destroy(win->xdg_toplevel_decoration);
    if (win->xdg_toplevel != NULL)
        xdg_toplevel_destroy(win->xdg_toplevel);
    if (win->xdg_surface != NULL)
        xdg_surface_destroy(win->xdg_surface);
    if (win->surface != NULL)
        wl_surface_destroy(win->surface);
    free(win);
}

struct terminal *
wayl_terminal_from_surface(struct wayland *wayl, struct wl_surface *surface)
{
    assert(surface == wayl->term->window->surface);
    return wayl->term;
}

struct terminal *
wayl_terminal_from_xdg_toplevel(struct wayland *wayl,
                                struct xdg_toplevel *toplevel)
{
    assert(toplevel == wayl->term->window->xdg_toplevel);
    return wayl->term;
}