掌機 - GKDmini Plus - Wayland Client (xdg-shell) - Redraw Pixel


參考資訊：
https://jan.newmarch.name/Wayland/index.html
https://wayland.freedesktop.org/docs/html/apa.html
https://bugaevc.gitbooks.io/writing-wayland-clients/content/

main.c 

#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <wayland-client.h>
#include <linux/input-event-codes.h>
 
#include "xdg-shell-client-protocol.h"
 
#define WIDTH  640
#define HEIGHT 480
#define STRIDE (WIDTH * 2)
#define SIZE   (STRIDE * HEIGHT)
    
static bool configured = false;
static bool running = true;
 
uint16_t *addr = NULL;
struct wl_shm *shm = NULL;
struct wl_buffer *buf = NULL; 
struct wl_display *dis = NULL;
struct wl_surface *surf = NULL;
struct wl_registry *reg = NULL;
struct wl_shm_pool *pool = NULL;
struct wl_callback *frame = NULL;
struct wl_compositor *comp = NULL;
struct xdg_surface *xdg_surf = NULL;
struct xdg_toplevel *xdg_toplevel = NULL;
struct xdg_wm_base *xdg_wm_base = NULL;
 
void cb_redraw(void *dat, struct wl_callback *cb, uint32_t time);
 
static void xdg_wm_base_handle_ping(void *data, struct xdg_wm_base *xdg_wm_base, uint32_t serial)
{
    xdg_wm_base_pong(xdg_wm_base, serial);
}
 
static const struct xdg_wm_base_listener xdg_wm_base_listener = {
    .ping = xdg_wm_base_handle_ping,
};
  
void cb_handle(void *dat, struct wl_registry *reg, uint32_t id, const char *intf, uint32_t ver)
{
    if (strcmp(intf, wl_compositor_interface.name) == 0) {
        comp = wl_registry_bind(reg, id, &wl_compositor_interface, 1);
    }
    else if (strcmp(intf, xdg_wm_base_interface.name) == 0) {
        xdg_wm_base = wl_registry_bind(reg, id, &xdg_wm_base_interface, 1);
        xdg_wm_base_add_listener(xdg_wm_base, &xdg_wm_base_listener, NULL);
    }
    else if (strcmp(intf, wl_shm_interface.name) == 0) {
        shm = wl_registry_bind(reg, id, &wl_shm_interface, 1);
    }
}
      
void cb_remove(void *dat, struct wl_registry *reg, uint32_t id)
{
}
      
struct wl_registry_listener cb = {
    .global = cb_handle,
    .global_remove = cb_remove
};
 
static void xdg_surface_handle_configure(void *data, struct xdg_surface *xdg_surface, uint32_t serial)
{
    xdg_surface_ack_configure(xdg_surface, serial);
 
    if (configured) {
        wl_surface_commit(surf);
    }
 
    configured = true;
}
 
static const struct xdg_surface_listener xdg_surface_listener = {
    .configure = xdg_surface_handle_configure,
};
 
static void xdg_toplevel_handle_close(void *data, struct xdg_toplevel *xdg_toplevel)
{
    running = false;
}
 
static void noop(void *arg0, struct xdg_toplevel *arg1, int32_t arg2, int32_t arg3, struct wl_array *arg4)
{
}
 
static const struct xdg_toplevel_listener xdg_toplevel_listener = {
    .configure = noop,
    .close = xdg_toplevel_handle_close,
};
 
const struct wl_callback_listener cb_frame = {
    cb_redraw
};
 
void cb_redraw(void *dat, struct wl_callback *cb, uint32_t time)
{
    static int cnt = 0;
    wl_callback_destroy(frame);
    wl_surface_damage(surf, 0, 0, WIDTH, HEIGHT);
   
    int x = 0, y = 0;
    uint16_t *p = addr;
    uint16_t col[] = { 0xf800, 0x7e0, 0x1f };
    for (y = 0; y < HEIGHT; y++) {
        for (x = 0; x < WIDTH; x++) {
            *p++ = col[cnt % 3];
        }
    }
    cnt+= 1;
   
    frame = wl_surface_frame(surf);
    wl_surface_attach(surf, buf, 0, 0);
    wl_callback_add_listener(frame, &cb_frame, NULL);
    wl_surface_commit(surf);
}
 
int main(int argc, char **argv)
{
    dis = wl_display_connect(NULL);
    reg = wl_display_get_registry(dis);
  
    wl_registry_add_listener(reg, &cb, NULL);
    wl_display_roundtrip(dis);
    printf("comp = 0x%08x\n", comp);
 
    surf = wl_compositor_create_surface(comp);
    printf("surf = 0x%08x\n", surf);
 
    xdg_surf = xdg_wm_base_get_xdg_surface(xdg_wm_base, surf);
    printf("xdg_surf = 0x%08x\n", xdg_surf);
 
    xdg_toplevel = xdg_surface_get_toplevel(xdg_surf);
    xdg_surface_add_listener(xdg_surf, &xdg_surface_listener, NULL);
    xdg_toplevel_add_listener(xdg_toplevel, &xdg_toplevel_listener, NULL);
 
    wl_surface_commit(surf);
    while (wl_display_dispatch(dis) != -1 && !configured) {
    }
 
    unlink("/tmp/shm");
    int fd = open("/tmp/shm", O_RDWR | O_EXCL | O_CREAT);
    ftruncate(fd, SIZE);
 
    addr = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
    pool = wl_shm_create_pool(shm, fd, SIZE);
    buf = wl_shm_pool_create_buffer(pool, 0, WIDTH, HEIGHT, STRIDE, WL_SHM_FORMAT_RGB565);
    wl_shm_pool_destroy(pool);
 
    frame = wl_surface_frame(surf);
    wl_callback_add_listener(frame, &cb_frame, NULL);
   
    wl_surface_attach(surf, buf, 0, 0);
    wl_surface_commit(surf);
   
    while (1) {
        wl_display_dispatch(dis);
    }
 
    wl_callback_destroy(frame);
    xdg_toplevel_destroy(xdg_toplevel);
    xdg_surface_destroy(xdg_surf);
    wl_surface_destroy(surf);
    wl_shm_destroy(shm);
    wl_compositor_destroy(comp);
    wl_registry_destroy(reg);
    wl_display_disconnect(dis);
    munmap(addr, SIZE);
    close(fd);
    return 0;
}

編譯 

$ /opt/mini/bin/wayland-scanner private-code /opt/mini/arm-buildroot-linux-gnueabihf/sysroot/usr/share/waylandpp/protocols/xdg-shell.xml xdg-shell-protocol.c
$ /opt/mini/bin/wayland-scanner client-header /opt/mini/arm-buildroot-linux-gnueabihf/sysroot/usr/share/waylandpp/protocols/xdg-shell.xml xdg-shell-client-protocol.h
$ arm-linux-gnueabihf-gcc main.c xdg-shell-protocol.c -o test -I/opt/mini/include -lwayland-client

執行 

# killall gmenu2x && ./test 
    comp = 0x017eb788
    surf = 0x017ea480
    xdg_surf = 0x017ea4b8
    pool = 0x17ea110
    buf = 0x17ea2f0
    mmap = 0xf77cd000