手機 - Motorola XT894 - Sailfish OS - Wayland (OpenGL ES 2.0) - Get Version

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/
https://gist.github.com/Miouyouyou/ca15af1c7f2696f66b0e013058f110b4

main.c

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wayland-egl.h>
#include <wayland-client.h>
#include <EGL/egl.h>
#include <GLES2/gl2.h>

#define LCD_W   540
#define LCD_H   960
 
struct wl_shell *shell = NULL;
struct wl_display *dis = NULL;
struct wl_surface *surf = NULL;
struct wl_registry *reg = NULL;
struct wl_region *regn = NULL;
struct wl_compositor *comp = NULL;
struct wl_egl_window *egl_win = NULL;
struct wl_shell_surface *shell_surf = NULL;
 
EGLConfig egl_conf = 0;
EGLContext egl_ctx = 0;
EGLDisplay egl_dis = 0;
EGLSurface egl_surf = 0;
 
EGLint egl_attribs[] = {
    EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
    EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
    EGL_RED_SIZE,   8,
    EGL_GREEN_SIZE, 8,
    EGL_BLUE_SIZE,  8,
    EGL_NONE
};
 
EGLint ctx_attribs[] = {
    EGL_CONTEXT_CLIENT_VERSION, 
    2, 
    EGL_NONE
};
 
void cb_handle(void *dat, struct wl_registry *reg, uint32_t id, const char *intf, uint32_t ver)
{
    if (strcmp(intf, "wl_compositor") == 0) {
        comp = wl_registry_bind(reg, id, &wl_compositor_interface, 3);
    }
    else if (strcmp(intf, "wl_shell") == 0) {
        shell = wl_registry_bind(reg, id, &wl_shell_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
};
 
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_dispatch(dis);
    wl_display_roundtrip(dis);
 
    surf = wl_compositor_create_surface(comp);
    shell_surf = wl_shell_get_shell_surface(shell, surf);
    wl_shell_surface_set_toplevel(shell_surf);
 
    regn = wl_compositor_create_region(comp);
    wl_region_add(regn, 0, 0, LCD_W, LCD_H);
    wl_surface_set_opaque_region(surf, regn);
    egl_win = wl_egl_window_create(surf, LCD_W, LCD_H);
 
    EGLConfig cfg = 0;
    EGLint major = 0, minor = 0, cnt = 0;
 
    egl_dis = eglGetDisplay((EGLNativeDisplayType)dis);
    eglInitialize(egl_dis, &major, &minor);
    eglGetConfigs(egl_dis, NULL, 0, &cnt);
    eglChooseConfig(egl_dis, egl_attribs, &cfg, 1, &cnt);
    egl_surf = eglCreateWindowSurface(egl_dis, cfg, egl_win, NULL);
    egl_ctx = eglCreateContext(egl_dis, cfg, EGL_NO_CONTEXT, ctx_attribs);
    eglMakeCurrent(egl_dis, egl_surf, egl_surf, egl_ctx);
    printf("egl_diplay = 0x%08x\n", egl_dis);
    printf("egl major:%d, minor:%d\n", major, minor);
 
    glClearColor(1.0, 0.0, 0.0, 1.0);
    glClear(GL_COLOR_BUFFER_BIT);
    eglSwapBuffers(egl_dis, egl_surf);
 
    eglTerminate(egl_dis);
    eglDestroySurface(egl_dis, egl_surf);
    eglDestroyContext(egl_dis, egl_ctx);
    wl_egl_window_destroy(egl_win);
     
    wl_region_destroy(regn);
    wl_shell_surface_destroy(shell_surf);
    wl_shell_destroy(shell);
    wl_surface_destroy(surf);
    wl_compositor_destroy(comp);
    wl_registry_destroy(reg);
    wl_display_disconnect(dis);
    return 0;
}

編譯、執行

$ gcc main.c -o main -lwayland-client -lwayland-egl -lEGL -lGLESv2
$ ./main
    egl_diplay = 0x00000001
    egl major:1, minor:4