Merge pull request #236 from ascent12/gl-loader

Add GL/EGL extension loader generator

9 files changed, 143 insertions, 77 deletions

diff --git a/backend/drm/renderer.c b/backend/drm/renderer.c
index c5840436..0d338490 100644
--- a/backend/drm/renderer.c
+++ b/backend/drm/renderer.c
@@ -14,6 +14,7 @@
 #include <wlr/render/gles2.h>
 #include <wlr/render.h>
 #include "backend/drm/drm.h"
+#include "render/glapi.h"
 
 bool wlr_drm_renderer_init(struct wlr_drm_backend *drm,
 		struct wlr_drm_renderer *renderer) {
@@ -191,7 +192,7 @@ static struct wlr_texture *get_tex_for_bo(struct wlr_drm_renderer *renderer, str
 		EGL_NONE,
 	};
 
-	tex->img = renderer->egl.eglCreateImageKHR(renderer->egl.display, EGL_NO_CONTEXT,
+	tex->img = eglCreateImageKHR(renderer->egl.display, EGL_NO_CONTEXT,
 		EGL_LINUX_DMA_BUF_EXT, NULL, attribs);
 	if (!tex->img) {
 		wlr_log(L_ERROR, "Failed to create EGL image: %s", egl_error());
diff --git a/backend/meson.build b/backend/meson.build
index c5c73288..cf62a56f 100644
--- a/backend/meson.build
+++ b/backend/meson.build
@@ -38,5 +38,5 @@ lib_wlr_backend = static_library(
 	'wlr_backend',
 	backend_files,
 	include_directories: wlr_inc,
-	dependencies: [wayland_server, egl, gbm, libinput, systemd, elogind, wlr_protos],
+	dependencies: [wayland_server, egl, gbm, libinput, systemd, elogind, wlr_render, wlr_protos],
 )
diff --git a/glgen.sh b/glgen.sh
new file mode 100755
index 00000000..d9de6f9f
--- /dev/null
+++ b/glgen.sh
@@ -0,0 +1,91 @@
+#!/bin/sh
+
+# Generates a simple GL/EGL extension function loader.
+#
+# The input is a .txt file, with each function to load on its own line.
+# If a line starts with a -, it is optional, and will not cause the loader
+# to fail if it can't load the function. You'll need to check if that function
+# is NULL before using it.
+
+if [ $# -ne 2 ]; then
+	exit 1
+fi
+
+SPEC=$1
+OUT=$2
+
+BASE=$(basename "$SPEC" .txt)
+INCLUDE_GUARD=$(printf %s "$SPEC" | tr -c [:alnum:] _ | tr [:lower:] [:upper:])
+
+DECL=""
+DEFN=""
+LOADER=""
+
+DECL_FMT='extern %s %s;'
+DEFN_FMT='%s %s;'
+LOADER_FMT='%s = (%s)eglGetProcAddress("%s");'
+CHECK_FMT='if (!%s) {
+	wlr_log(L_ERROR, "Unable to load %s");
+	return false;
+}'
+
+while read -r COMMAND; do
+	[ ${COMMAND::1} = "-" ]
+	OPTIONAL=$?
+
+	COMMAND=${COMMAND#-}
+	if [ ${COMMAND: -2} = "WL" ]; then
+		FUNC_PTR_FMT='PFN%s'
+	else
+		FUNC_PTR_FMT='PFN%sPROC'
+	fi
+
+	FUNC_PTR=$(printf "$FUNC_PTR_FMT" "$COMMAND" | tr [:lower:] [:upper:])
+
+	DECL="$DECL$(printf "\n$DECL_FMT" "$FUNC_PTR" "$COMMAND")"
+	DEFN="$DEFN$(printf "\n$DEFN_FMT" "$FUNC_PTR" "$COMMAND")"
+	LOADER="$LOADER$(printf "\n$LOADER_FMT" "$COMMAND" "$FUNC_PTR" "$COMMAND")"
+
+	if [ $OPTIONAL -ne 0 ]; then
+		LOADER="$LOADER$(printf "\n$CHECK_FMT" "$COMMAND" "$COMMAND")"
+	fi
+done < $SPEC
+
+if [ ${OUT: -2} = '.h' ]; then
+	cat > $OUT << EOF
+	#ifndef $INCLUDE_GUARD
+	#define $INCLUDE_GUARD
+
+	#include <stdbool.h>
+
+	#include <EGL/egl.h>
+	#include <EGL/eglext.h>
+	#include <EGL/eglmesaext.h>
+	#include <GLES2/gl2.h>
+	#include <GLES2/gl2ext.h>
+
+	bool load_$BASE(void);
+	$DECL
+
+	#endif
+EOF
+elif [ ${OUT: -2} = '.c' ]; then
+	cat > $OUT << EOF
+	#include <wlr/util/log.h>
+	#include "$BASE.h"
+	$DEFN
+
+	bool load_$BASE(void) {
+		static bool done = false;
+		if (done) {
+			return true;
+		}
+	$LOADER
+
+		done = true;
+		return true;
+	}
+EOF
+else
+	exit 1
+fi
diff --git a/include/wlr/egl.h b/include/wlr/egl.h
index 25329175..9ab4d9ce 100644
--- a/include/wlr/egl.h
+++ b/include/wlr/egl.h
@@ -10,15 +10,6 @@ struct wlr_egl {
 	EGLConfig config;
 	EGLContext context;
 
-	PFNEGLGETPLATFORMDISPLAYEXTPROC get_platform_display;
-	PFNEGLCREATEPLATFORMWINDOWSURFACEEXTPROC create_platform_window_surface;
-
-	PFNEGLCREATEIMAGEKHRPROC eglCreateImageKHR;
-	PFNEGLDESTROYIMAGEKHRPROC eglDestroyImageKHR;
-	PFNEGLQUERYWAYLANDBUFFERWL eglQueryWaylandBufferWL;
-	PFNEGLBINDWAYLANDDISPLAYWL eglBindWaylandDisplayWL;
-	PFNEGLUNBINDWAYLANDDISPLAYWL eglUnbindWaylandDisplayWL;
-
 	const char *egl_exts;
 	const char *gl_exts;
 
diff --git a/meson.build b/meson.build
index 57c26b0f..179550d6 100644
--- a/meson.build
+++ b/meson.build
@@ -14,6 +14,10 @@ add_project_arguments(
 	'-DWLR_SRC_DIR="@0@"'.format(meson.source_root()),
 	language: 'c',
 )
+add_project_arguments(
+	'-I@0@'.format(meson.build_root()),
+	language: 'c',
+)
 add_project_link_arguments(
 	'-Wl,-rpath,@0@'.format(meson.build_root()),
 	language: 'c',
@@ -69,8 +73,8 @@ if elogind.found() and get_option('enable_elogind')
 endif
 
 subdir('protocol')
-subdir('backend')
 subdir('render')
+subdir('backend')
 subdir('types')
 subdir('util')
 subdir('xcursor')
diff --git a/render/egl.c b/render/egl.c
index 82dea50c..9815b923 100644
--- a/render/egl.c
+++ b/render/egl.c
@@ -4,6 +4,7 @@
 #include <stdlib.h>
 #include <wlr/util/log.h>
 #include <wlr/egl.h>
+#include "render/glapi.h"
 
 // Extension documentation
 // https://www.khronos.org/registry/EGL/extensions/KHR/EGL_KHR_image_base.txt.
@@ -46,27 +47,6 @@ const char *egl_error(void) {
 	}
 }
 
-static bool egl_exts(struct wlr_egl *egl) {
-	egl->get_platform_display = (PFNEGLGETPLATFORMDISPLAYEXTPROC)
-		eglGetProcAddress("eglGetPlatformDisplayEXT");
-
-	if (!egl->get_platform_display) {
-		wlr_log(L_ERROR, "Failed to load EGL extension 'eglGetPlatformDisplayEXT'");
-		return false;
-	}
-
-	egl->create_platform_window_surface = (PFNEGLCREATEPLATFORMWINDOWSURFACEEXTPROC)
-		eglGetProcAddress("eglCreatePlatformWindowSurfaceEXT");
-
-	if (!egl->create_platform_window_surface) {
-		wlr_log(L_ERROR,
-			"Failed to load EGL extension 'eglCreatePlatformWindowSurfaceEXT'");
-		return false;
-	}
-
-	return true;
-}
-
 static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
 	EGLint count = 0, matched = 0, ret;
 
@@ -103,7 +83,7 @@ static bool egl_get_config(EGLDisplay disp, EGLConfig *out, EGLint visual_id) {
 
 bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
 		void *remote_display) {
-	if (!egl_exts(egl)) {
+	if (!load_glapi()) {
 		return false;
 	}
 
@@ -112,7 +92,7 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
 		goto error;
 	}
 
-	egl->display = egl->get_platform_display(platform, remote_display, NULL);
+	egl->display = eglGetPlatformDisplayEXT(platform, remote_display, NULL);
 	if (egl->display == EGL_NO_DISPLAY) {
 		wlr_log(L_ERROR, "Failed to create EGL display: %s", egl_error());
 		goto error;
@@ -142,22 +122,11 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, EGLint visual_id,
 	eglMakeCurrent(egl->display, EGL_NO_SURFACE, EGL_NO_SURFACE, egl->context);
 	egl->egl_exts = eglQueryString(egl->display, EGL_EXTENSIONS);
 	if (strstr(egl->egl_exts, "EGL_WL_bind_wayland_display") == NULL ||
-		strstr(egl->egl_exts, "EGL_KHR_image_base") == NULL) {
+			strstr(egl->egl_exts, "EGL_KHR_image_base") == NULL) {
 		wlr_log(L_ERROR, "Required egl extensions not supported");
 		goto error;
 	}
 
-	egl->eglCreateImageKHR = (PFNEGLCREATEIMAGEKHRPROC)
-		eglGetProcAddress("eglCreateImageKHR");
-	egl->eglDestroyImageKHR = (PFNEGLDESTROYIMAGEKHRPROC)
-		eglGetProcAddress("eglDestroyImageKHR");
-	egl->eglQueryWaylandBufferWL = (PFNEGLQUERYWAYLANDBUFFERWL)
-		(void*) eglGetProcAddress("eglQueryWaylandBufferWL");
-	egl->eglBindWaylandDisplayWL = (PFNEGLBINDWAYLANDDISPLAYWL)
-		(void*) eglGetProcAddress("eglBindWaylandDisplayWL");
-	egl->eglUnbindWaylandDisplayWL = (PFNEGLUNBINDWAYLANDDISPLAYWL)
-		(void*) eglGetProcAddress("eglUnbindWaylandDisplayWL");
-
 	egl->gl_exts = (const char*) glGetString(GL_EXTENSIONS);
 	wlr_log(L_INFO, "Using EGL %d.%d", (int)major, (int)minor);
 	wlr_log(L_INFO, "Supported EGL extensions: %s", egl->egl_exts);
@@ -174,8 +143,8 @@ error:
 
 void wlr_egl_free(struct wlr_egl *egl) {
 	eglMakeCurrent(EGL_NO_DISPLAY, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
-	if (egl->wl_display && egl->eglUnbindWaylandDisplayWL) {
-		egl->eglUnbindWaylandDisplayWL(egl->display, egl->wl_display);
+	if (egl->wl_display && eglUnbindWaylandDisplayWL) {
+		eglUnbindWaylandDisplayWL(egl->display, egl->wl_display);
 	}
 
 	eglDestroyContext(egl->display, egl->context);
@@ -184,11 +153,11 @@ void wlr_egl_free(struct wlr_egl *egl) {
 }
 
 bool wlr_egl_bind_display(struct wlr_egl *egl, struct wl_display *local_display) {
-	if (!egl->eglBindWaylandDisplayWL) {
+	if (!eglBindWaylandDisplayWL) {
 		return false;
 	}
 
-	if (egl->eglBindWaylandDisplayWL(egl->display, local_display)) {
+	if (eglBindWaylandDisplayWL(egl->display, local_display)) {
 		egl->wl_display = local_display;
 		return true;
 	}
@@ -198,33 +167,33 @@ bool wlr_egl_bind_display(struct wlr_egl *egl, struct wl_display *local_display)
 
 bool wlr_egl_query_buffer(struct wlr_egl *egl, struct wl_resource *buf,
 		int attrib, int *value) {
-	if (!egl->eglQueryWaylandBufferWL) {
+	if (!eglQueryWaylandBufferWL) {
 		return false;
 	}
-	return egl->eglQueryWaylandBufferWL(egl->display, buf, attrib, value);
+	return eglQueryWaylandBufferWL(egl->display, buf, attrib, value);
 }
 
 EGLImage wlr_egl_create_image(struct wlr_egl *egl, EGLenum target,
 		EGLClientBuffer buffer, const EGLint *attribs) {
-	if (!egl->eglCreateImageKHR) {
+	if (!eglCreateImageKHR) {
 		return false;
 	}
 
-	return egl->eglCreateImageKHR(egl->display, egl->context, target,
+	return eglCreateImageKHR(egl->display, egl->context, target,
 		buffer, attribs);
 }
 
 bool wlr_egl_destroy_image(struct wlr_egl *egl, EGLImage image) {
-	if (!egl->eglDestroyImageKHR) {
+	if (!eglDestroyImageKHR) {
 		return false;
 	}
 
-	egl->eglDestroyImageKHR(egl->display, image);
+	eglDestroyImageKHR(egl->display, image);
 	return true;
 }
 
 EGLSurface wlr_egl_create_surface(struct wlr_egl *egl, void *window) {
-	EGLSurface surf = egl->create_platform_window_surface(egl->display, egl->config,
+	EGLSurface surf = eglCreatePlatformWindowSurfaceEXT(egl->display, egl->config,
 		window, NULL);
 	if (surf == EGL_NO_SURFACE) {
 		wlr_log(L_ERROR, "Failed to create EGL surface: %s", egl_error());
diff --git a/render/glapi.txt b/render/glapi.txt
new file mode 100644
index 00000000..81791204
--- /dev/null
+++ b/render/glapi.txt
@@ -0,0 +1,8 @@
+eglGetPlatformDisplayEXT
+eglCreatePlatformWindowSurfaceEXT
+-eglCreateImageKHR
+-eglDestroyImageKHR
+-eglQueryWaylandBufferWL
+-eglBindWaylandDisplayWL
+-eglUnbindWaylandDisplayWL
+-glEGLImageTargetTexture2DOES
diff --git a/render/gles2/renderer.c b/render/gles2/renderer.c
index d6c22ebe..325e1571 100644
--- a/render/gles2/renderer.c
+++ b/render/gles2/renderer.c
@@ -12,8 +12,8 @@
 #include <wlr/render/matrix.h>
 #include <wlr/util/log.h>
 #include "render/gles2.h"
+#include "render/glapi.h"
 
-PFNGLEGLIMAGETARGETTEXTURE2DOESPROC glEGLImageTargetTexture2DOES = NULL;
 struct shaders shaders;
 
 static bool compile_shader(GLuint type, const GLchar *src, GLuint *shader) {
@@ -101,25 +101,7 @@ error:
 	wlr_log(L_ERROR, "Failed to set up default shaders!");
 }
 
-static void init_image_ext() {
-	if (glEGLImageTargetTexture2DOES) {
-		return;
-	}
-
-	const char *exts = (const char*) glGetString(GL_EXTENSIONS);
-	if (strstr(exts, "GL_OES_EGL_image_external")) {
- 		glEGLImageTargetTexture2DOES = (PFNGLEGLIMAGETARGETTEXTURE2DOESPROC)
-			eglGetProcAddress("glEGLImageTargetTexture2DOES");
-	}
-
-	if (!glEGLImageTargetTexture2DOES) {
-		wlr_log(L_INFO, "Failed to load glEGLImageTargetTexture2DOES "
-			"Will not be able to attach drm buffers");
-	}
-}
-
 static void init_globals() {
-	init_image_ext();
 	init_default_shaders();
 }
 
diff --git a/render/meson.build b/render/meson.build
index dc0ceeb9..749d1393 100644
--- a/render/meson.build
+++ b/render/meson.build
@@ -1,3 +1,16 @@
+glgen = find_program('../glgen.sh')
+
+glapi_c = custom_target('glapi.c',
+	input: 'glapi.txt',
+	output: '@BASENAME@.c',
+	command: [glgen, '@INPUT@', '@OUTPUT@'],
+)
+glapi_h = custom_target('glapi.h',
+	input: 'glapi.txt',
+	output: '@BASENAME@.h',
+	command: [glgen, '@INPUT@', '@OUTPUT@'],
+)
+
 lib_wlr_render = static_library(
 	'wlr_render',
 	files(
@@ -11,6 +24,13 @@ lib_wlr_render = static_library(
 		'wlr_renderer.c',
 		'wlr_texture.c',
 	),
+	glapi_c,
+	glapi_h,
 	include_directories: wlr_inc,
 	dependencies: [glesv2, egl],
 )
+
+wlr_render = declare_dependency(
+	link_with: lib_wlr_render,
+	sources: glapi_h,
+)