Refactor EGL/GL API loading

Remove glapi.sh code generation, replace it with hand-written loading
code that checks extension strings before calling eglGetProcAddress.

The GLES2 renderer still uses global state because of:

- {PUSH,POP}_GLES2_DEBUG macros
- wlr_gles2_texture_from_* taking a wlr_egl instead of the renderer

11 files changed, 191 insertions, 245 deletions

diff --git a/backend/drm/renderer.c b/backend/drm/renderer.c
index 9edf7632..25101a4b 100644
--- a/backend/drm/renderer.c
+++ b/backend/drm/renderer.c
@@ -11,7 +11,6 @@
 #include <wlr/types/wlr_matrix.h>
 #include <wlr/util/log.h>
 #include "backend/drm/drm.h"
-#include "glapi.h"
 
 bool init_drm_renderer(struct wlr_drm_backend *drm,
 		struct wlr_drm_renderer *renderer, wlr_renderer_create_func_t create_renderer_func) {
diff --git a/backend/headless/backend.c b/backend/headless/backend.c
index c0fc6022..d6bb141a 100644
--- a/backend/headless/backend.c
+++ b/backend/headless/backend.c
@@ -6,7 +6,6 @@
 #include <wlr/render/gles2.h>
 #include <wlr/util/log.h>
 #include "backend/headless.h"
-#include "glapi.h"
 #include "util/signal.h"
 
 struct wlr_headless_backend *headless_backend_from_backend(
diff --git a/backend/rdp/backend.c b/backend/rdp/backend.c
index ef0fca85..c0b63921 100644
--- a/backend/rdp/backend.c
+++ b/backend/rdp/backend.c
@@ -6,7 +6,6 @@
 #include <wlr/render/gles2.h>
 #include <wlr/util/log.h>
 #include "backend/rdp.h"
-#include "glapi.h"
 #include "util/signal.h"
 
 struct wlr_rdp_backend *rdp_backend_from_backend(
diff --git a/glgen.sh b/glgen.sh
deleted file mode 100755
index 31af2812..00000000
--- a/glgen.sh
+++ /dev/null
@@ -1,103 +0,0 @@
-#!/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
-OUTDIR=$2
-
-BASE=$(basename "$SPEC" .txt)
-INCLUDE_GUARD=$(printf %s_%s_H "$OUTDIR" "$BASE" | 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(WLR_ERROR, "Unable to load %s");
-	return false;
-}'
-
-while read -r COMMAND; do
-	OPTIONAL=0
-	FUNC_PTR_FMT='PFN%sPROC'
-
-	case $COMMAND in
-	-*)
-		OPTIONAL=1
-		;;
-	esac
-
-	case $COMMAND in
-	*WL)
-		FUNC_PTR_FMT='PFN%s'
-		;;
-	esac
-
-	COMMAND=${COMMAND#-}
-	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 [ $OPTIONAL -eq 0 ]; then
-		LOADER="$LOADER$(printf "\n$CHECK_FMT" "$COMMAND" "$COMMAND")"
-	fi
-done < "$SPEC"
-
-cat > "$OUTDIR/$BASE.h" << EOF
-#ifndef $INCLUDE_GUARD
-#define $INCLUDE_GUARD
-
-#include <stdbool.h>
-#include <wlr/config.h>
-
-#if !WLR_HAS_X11_BACKEND && !WLR_HAS_XWAYLAND
-#ifndef MESA_EGL_NO_X11_HEADERS
-#define MESA_EGL_NO_X11_HEADERS
-#endif
-#ifndef EGL_NO_X11
-#define EGL_NO_X11
-#endif
-#endif
-
-#include <EGL/egl.h>
-#include <EGL/eglext.h>
-#include <EGL/eglmesaext.h>
-#include <GLES2/gl2.h>
-#include <GLES2/gl2ext.h>
-
-bool load_$BASE(void);
-$DECL
-
-#endif
-EOF
-
-cat > "$OUTDIR/$BASE.c" << EOF
-#include <wlr/util/log.h>
-#include "$BASE.h"
-$DEFN
-
-bool load_$BASE(void) {
-    static bool done = false;
-    if (done) {
-        return true;
-    }
-$LOADER
-
-    done = true;
-    return true;
-}
-EOF
diff --git a/include/render/gles2.h b/include/render/gles2.h
index 7a629d69..817ec62d 100644
--- a/include/render/gles2.h
+++ b/include/render/gles2.h
@@ -14,6 +14,16 @@
 #include <wlr/render/wlr_texture.h>
 #include <wlr/util/log.h>
 
+struct wlr_gles2_procs {
+	PFNGLEGLIMAGETARGETTEXTURE2DOESPROC glEGLImageTargetTexture2DOES;
+	PFNGLDEBUGMESSAGECALLBACKKHRPROC glDebugMessageCallbackKHR;
+	PFNGLDEBUGMESSAGECONTROLKHRPROC glDebugMessageControlKHR;
+	PFNGLPOPDEBUGGROUPKHRPROC glPopDebugGroupKHR;
+	PFNGLPUSHDEBUGGROUPKHRPROC glPushDebugGroupKHR;
+};
+
+extern struct wlr_gles2_procs gles2_procs;
+
 struct wlr_gles2_pixel_format {
 	enum wl_shm_format wl_format;
 	GLint gl_format, gl_type;
@@ -33,7 +43,6 @@ struct wlr_gles2_renderer {
 	struct wlr_renderer wlr_renderer;
 
 	struct wlr_egl *egl;
-	const char *exts_str;
 
 	struct {
 		bool read_format_bgra_ext;
diff --git a/include/wlr/render/egl.h b/include/wlr/render/egl.h
index efded0b6..2853f8ed 100644
--- a/include/wlr/render/egl.h
+++ b/include/wlr/render/egl.h
@@ -22,6 +22,8 @@
 
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
+// TODO: remove eglmesaext.h
+#include <EGL/eglmesaext.h>
 #include <pixman.h>
 #include <stdbool.h>
 #include <wayland-server-core.h>
@@ -34,8 +36,6 @@ struct wlr_egl {
 	EGLConfig config;
 	EGLContext context;
 
-	const char *exts_str;
-
 	struct {
 		bool bind_wayland_display_wl;
 		bool buffer_age_ext;
@@ -43,10 +43,25 @@ struct wlr_egl {
 		bool image_dma_buf_export_mesa;
 		bool image_dmabuf_import_ext;
 		bool image_dmabuf_import_modifiers_ext;
-		bool swap_buffers_with_damage_ext;
-		bool swap_buffers_with_damage_khr;
+		bool swap_buffers_with_damage;
 	} exts;
 
+	struct {
+		PFNEGLGETPLATFORMDISPLAYEXTPROC eglGetPlatformDisplayEXT;
+		PFNEGLCREATEPLATFORMWINDOWSURFACEEXTPROC eglCreatePlatformWindowSurfaceEXT;
+		PFNEGLCREATEIMAGEKHRPROC eglCreateImageKHR;
+		PFNEGLDESTROYIMAGEKHRPROC eglDestroyImageKHR;
+		PFNEGLQUERYWAYLANDBUFFERWL eglQueryWaylandBufferWL;
+		PFNEGLBINDWAYLANDDISPLAYWL eglBindWaylandDisplayWL;
+		PFNEGLUNBINDWAYLANDDISPLAYWL eglUnbindWaylandDisplayWL;
+		PFNEGLSWAPBUFFERSWITHDAMAGEEXTPROC eglSwapBuffersWithDamage; // KHR or EXT
+		PFNEGLQUERYDMABUFFORMATSEXTPROC eglQueryDmaBufFormatsEXT;
+		PFNEGLQUERYDMABUFMODIFIERSEXTPROC eglQueryDmaBufModifiersEXT;
+		PFNEGLEXPORTDMABUFIMAGEQUERYMESAPROC eglExportDMABUFImageQueryMESA;
+		PFNEGLEXPORTDMABUFIMAGEMESAPROC eglExportDMABUFImageMESA;
+		PFNEGLDEBUGMESSAGECONTROLKHRPROC eglDebugMessageControlKHR;
+	} procs;
+
 	struct wl_display *wl_display;
 
 	struct wlr_drm_format_set dmabuf_formats;
diff --git a/render/egl.c b/render/egl.c
index cbd92cb9..14a7bf98 100644
--- a/render/egl.c
+++ b/render/egl.c
@@ -5,7 +5,6 @@
 #include <wlr/render/egl.h>
 #include <wlr/util/log.h>
 #include <wlr/util/region.h>
-#include "glapi.h"
 
 static bool egl_get_config(EGLDisplay disp, EGLint *attribs, EGLConfig *out,
 		EGLint visual_id) {
@@ -77,6 +76,15 @@ static bool check_egl_ext(const char *exts, const char *ext) {
 	return false;
 }
 
+static void load_egl_proc(void *proc_ptr, const char *name) {
+	void *proc = (void *)eglGetProcAddress(name);
+	if (proc == NULL) {
+		wlr_log(WLR_ERROR, "eglGetProcAddress(%s) failed", name);
+		abort();
+	}
+	*(void **)proc_ptr = proc;
+}
+
 static int get_egl_dmabuf_formats(struct wlr_egl *egl, int **formats);
 static int get_egl_dmabuf_modifiers(struct wlr_egl *egl, int format,
 	uint64_t **modifiers);
@@ -125,11 +133,72 @@ out:
 
 bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
 		EGLint *config_attribs, EGLint visual_id) {
-	if (!load_glapi()) {
+	const char *exts_str = eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS);
+	if (exts_str == NULL) {
+		wlr_log(WLR_ERROR, "Failed to query EGL extensions");
+		return false;
+	}
+
+	if (!check_egl_ext(exts_str, "EGL_EXT_platform_base")) {
+		wlr_log(WLR_ERROR, "EGL_EXT_platform_base not supported");
 		return false;
 	}
+	load_egl_proc(&egl->procs.eglGetPlatformDisplayEXT,
+		"eglGetPlatformDisplayEXT");
+	load_egl_proc(&egl->procs.eglCreatePlatformWindowSurfaceEXT,
+		"eglCreatePlatformWindowSurfaceEXT");
+
+	if (check_egl_ext(exts_str, "EGL_KHR_image_base")) {
+		egl->exts.image_base_khr = true;
+		load_egl_proc(&egl->procs.eglCreateImageKHR, "eglCreateImageKHR");
+		load_egl_proc(&egl->procs.eglDestroyImageKHR, "eglDestroyImageKHR");
+	}
+
+	egl->exts.buffer_age_ext =
+		check_egl_ext(exts_str, "EGL_EXT_buffer_age");
+
+	if (check_egl_ext(exts_str, "EGL_KHR_swap_buffers_with_damage")) {
+		egl->exts.swap_buffers_with_damage = true;
+		load_egl_proc(&egl->procs.eglSwapBuffersWithDamage,
+			"eglSwapBuffersWithDamageKHR");
+	} else if (check_egl_ext(exts_str, "EGL_EXT_swap_buffers_with_damage")) {
+		egl->exts.swap_buffers_with_damage = true;
+		load_egl_proc(&egl->procs.eglSwapBuffersWithDamage,
+			"eglSwapBuffersWithDamageEXT");
+	}
+
+	egl->exts.image_dmabuf_import_ext =
+		check_egl_ext(exts_str, "EGL_EXT_image_dma_buf_import");
+	if (check_egl_ext(exts_str, "EGL_EXT_image_dma_buf_import_modifiers")) {
+		egl->exts.image_dmabuf_import_modifiers_ext = true;
+		load_egl_proc(&egl->procs.eglQueryDmaBufFormatsEXT,
+			"eglQueryDmaBufFormatsEXT");
+		load_egl_proc(&egl->procs.eglQueryDmaBufModifiersEXT,
+			"eglQueryDmaBufModifiersEXT");
+	}
+
+	if (check_egl_ext(exts_str, "EGL_MESA_image_dma_buf_export")) {
+		egl->exts.image_dma_buf_export_mesa = true;
+		load_egl_proc(&egl->procs.eglExportDMABUFImageQueryMESA,
+			"eglExportDMABUFImageQueryMESA");
+		load_egl_proc(&egl->procs.eglExportDMABUFImageMESA,
+			"eglExportDMABUFImageMESA");
+	}
+
+	if (check_egl_ext(exts_str, "EGL_WL_bind_wayland_display")) {
+		egl->exts.bind_wayland_display_wl = true;
+		load_egl_proc(&egl->procs.eglBindWaylandDisplayWL,
+			"eglBindWaylandDisplayWL");
+		load_egl_proc(&egl->procs.eglUnbindWaylandDisplayWL,
+			"eglUnbindWaylandDisplayWL");
+		load_egl_proc(&egl->procs.eglQueryWaylandBufferWL,
+			"eglQueryWaylandBufferWL");
+	}
+
+	if (check_egl_ext(exts_str, "EGL_KHR_debug")) {
+		load_egl_proc(&egl->procs.eglDebugMessageControlKHR,
+			"eglDebugMessageControlKHR");
 
-	if (eglDebugMessageControlKHR) {
 		static const EGLAttrib debug_attribs[] = {
 			EGL_DEBUG_MSG_CRITICAL_KHR, EGL_TRUE,
 			EGL_DEBUG_MSG_ERROR_KHR, EGL_TRUE,
@@ -137,7 +206,7 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
 			EGL_DEBUG_MSG_INFO_KHR, EGL_TRUE,
 			EGL_NONE,
 		};
-		eglDebugMessageControlKHR(egl_log, debug_attribs);
+		egl->procs.eglDebugMessageControlKHR(egl_log, debug_attribs);
 	}
 
 	if (eglBindAPI(EGL_OPENGL_ES_API) == EGL_FALSE) {
@@ -147,9 +216,11 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
 
 	if (platform == EGL_PLATFORM_SURFACELESS_MESA) {
 		assert(remote_display == NULL);
-		egl->display = eglGetPlatformDisplayEXT(platform, EGL_DEFAULT_DISPLAY, NULL);
+		egl->display = egl->procs.eglGetPlatformDisplayEXT(platform,
+			EGL_DEFAULT_DISPLAY, NULL);
 	} else {
-		egl->display = eglGetPlatformDisplayEXT(platform, remote_display, NULL);
+		egl->display = egl->procs.eglGetPlatformDisplayEXT(platform,
+			remote_display, NULL);
 	}
 	if (egl->display == EGL_NO_DISPLAY) {
 		wlr_log(WLR_ERROR, "Failed to create EGL display");
@@ -169,44 +240,14 @@ bool wlr_egl_init(struct wlr_egl *egl, EGLenum platform, void *remote_display,
 		goto error;
 	}
 
-	egl->exts_str = eglQueryString(egl->display, EGL_EXTENSIONS);
-
 	wlr_log(WLR_INFO, "Using EGL %d.%d", (int)major, (int)minor);
-	wlr_log(WLR_INFO, "Supported EGL extensions: %s", egl->exts_str);
+	wlr_log(WLR_INFO, "Supported EGL extensions: %s", exts_str);
 	wlr_log(WLR_INFO, "EGL vendor: %s", eglQueryString(egl->display, EGL_VENDOR));
 
-	egl->exts.image_base_khr =
-		check_egl_ext(egl->exts_str, "EGL_KHR_image_base")
-		&& eglCreateImageKHR && eglDestroyImageKHR;
-
-	egl->exts.buffer_age_ext =
-		check_egl_ext(egl->exts_str, "EGL_EXT_buffer_age");
-	egl->exts.swap_buffers_with_damage_ext =
-		(check_egl_ext(egl->exts_str, "EGL_EXT_swap_buffers_with_damage") &&
-			eglSwapBuffersWithDamageEXT);
-	egl->exts.swap_buffers_with_damage_khr =
-		(check_egl_ext(egl->exts_str, "EGL_KHR_swap_buffers_with_damage") &&
-			eglSwapBuffersWithDamageKHR);
-
-	egl->exts.image_dmabuf_import_ext =
-		check_egl_ext(egl->exts_str, "EGL_EXT_image_dma_buf_import");
-	egl->exts.image_dmabuf_import_modifiers_ext =
-		check_egl_ext(egl->exts_str, "EGL_EXT_image_dma_buf_import_modifiers")
-		&& eglQueryDmaBufFormatsEXT && eglQueryDmaBufModifiersEXT;
-
-	egl->exts.image_dma_buf_export_mesa =
-		check_egl_ext(egl->exts_str, "EGL_MESA_image_dma_buf_export") &&
-		eglExportDMABUFImageQueryMESA && eglExportDMABUFImageMESA;
-
 	init_dmabuf_formats(egl);
 
-	egl->exts.bind_wayland_display_wl =
-		check_egl_ext(egl->exts_str, "EGL_WL_bind_wayland_display")
-		&& eglBindWaylandDisplayWL && eglUnbindWaylandDisplayWL
-		&& eglQueryWaylandBufferWL;
-
 	bool ext_context_priority =
-		check_egl_ext(egl->exts_str, "EGL_IMG_context_priority");
+		check_egl_ext(exts_str, "EGL_IMG_context_priority");
 
 	size_t atti = 0;
 	EGLint attribs[5];
@@ -272,7 +313,7 @@ void wlr_egl_finish(struct wlr_egl *egl) {
 	eglMakeCurrent(egl->display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
 	if (egl->wl_display) {
 		assert(egl->exts.bind_wayland_display_wl);
-		eglUnbindWaylandDisplayWL(egl->display, egl->wl_display);
+		egl->procs.eglUnbindWaylandDisplayWL(egl->display, egl->wl_display);
 	}
 
 	eglDestroyContext(egl->display, egl->context);
@@ -285,7 +326,7 @@ bool wlr_egl_bind_display(struct wlr_egl *egl, struct wl_display *local_display)
 		return false;
 	}
 
-	if (eglBindWaylandDisplayWL(egl->display, local_display)) {
+	if (egl->procs.eglBindWaylandDisplayWL(egl->display, local_display)) {
 		egl->wl_display = local_display;
 		return true;
 	}
@@ -300,13 +341,13 @@ bool wlr_egl_destroy_image(struct wlr_egl *egl, EGLImage image) {
 	if (!image) {
 		return true;
 	}
-	return eglDestroyImageKHR(egl->display, image);
+	return egl->procs.eglDestroyImageKHR(egl->display, image);
 }
 
 EGLSurface wlr_egl_create_surface(struct wlr_egl *egl, void *window) {
-	assert(eglCreatePlatformWindowSurfaceEXT);
-	EGLSurface surf = eglCreatePlatformWindowSurfaceEXT(egl->display,
-		egl->config, window, NULL);
+	assert(egl->procs.eglCreatePlatformWindowSurfaceEXT);
+	EGLSurface surf = egl->procs.eglCreatePlatformWindowSurfaceEXT(
+		egl->display, egl->config, window, NULL);
 	if (surf == EGL_NO_SURFACE) {
 		wlr_log(WLR_ERROR, "Failed to create EGL surface");
 		return EGL_NO_SURFACE;
@@ -355,8 +396,7 @@ bool wlr_egl_swap_buffers(struct wlr_egl *egl, EGLSurface surface,
 	}
 
 	EGLBoolean ret;
-	if (damage != NULL && (egl->exts.swap_buffers_with_damage_ext ||
-				egl->exts.swap_buffers_with_damage_khr)) {
+	if (damage != NULL && egl->exts.swap_buffers_with_damage) {
 		EGLint width = 0, height = 0;
 		eglQuerySurface(egl->display, surface, EGL_WIDTH, &width);
 		eglQuerySurface(egl->display, surface, EGL_HEIGHT, &height);
@@ -387,13 +427,8 @@ bool wlr_egl_swap_buffers(struct wlr_egl *egl, EGLSurface surface,
 			memset(egl_damage, 0, sizeof(egl_damage));
 		}
 
-		if (egl->exts.swap_buffers_with_damage_ext) {
-			ret = eglSwapBuffersWithDamageEXT(egl->display, surface, egl_damage,
-				nrects);
-		} else {
-			ret = eglSwapBuffersWithDamageKHR(egl->display, surface, egl_damage,
-				nrects);
-		}
+		ret = egl->procs.eglSwapBuffersWithDamage(egl->display, surface,
+			egl_damage, nrects);
 	} else {
 		ret = eglSwapBuffers(egl->display, surface);
 	}
@@ -412,16 +447,17 @@ EGLImageKHR wlr_egl_create_image_from_wl_drm(struct wlr_egl *egl,
 		return NULL;
 	}
 
-	if (!eglQueryWaylandBufferWL(egl->display, data, EGL_TEXTURE_FORMAT, fmt)) {
+	if (!egl->procs.eglQueryWaylandBufferWL(egl->display, data,
+			EGL_TEXTURE_FORMAT, fmt)) {
 		return NULL;
 	}
 
-	eglQueryWaylandBufferWL(egl->display, data, EGL_WIDTH, width);
-	eglQueryWaylandBufferWL(egl->display, data, EGL_HEIGHT, height);
+	egl->procs.eglQueryWaylandBufferWL(egl->display, data, EGL_WIDTH, width);
+	egl->procs.eglQueryWaylandBufferWL(egl->display, data, EGL_HEIGHT, height);
 
 	EGLint _inverted_y;
-	if (eglQueryWaylandBufferWL(egl->display, data, EGL_WAYLAND_Y_INVERTED_WL,
-			&_inverted_y)) {
+	if (egl->procs.eglQueryWaylandBufferWL(egl->display, data,
+			EGL_WAYLAND_Y_INVERTED_WL, &_inverted_y)) {
 		*inverted_y = !!_inverted_y;
 	} else {
 		*inverted_y = false;
@@ -431,8 +467,8 @@ EGLImageKHR wlr_egl_create_image_from_wl_drm(struct wlr_egl *egl,
 		EGL_WAYLAND_PLANE_WL, 0,
 		EGL_NONE,
 	};
-	return eglCreateImageKHR(egl->display, egl->context, EGL_WAYLAND_BUFFER_WL,
-		data, attribs);
+	return egl->procs.eglCreateImageKHR(egl->display, egl->context,
+		EGL_WAYLAND_BUFFER_WL, data, attribs);
 }
 
 EGLImageKHR wlr_egl_create_image_from_dmabuf(struct wlr_egl *egl,
@@ -517,7 +553,7 @@ EGLImageKHR wlr_egl_create_image_from_dmabuf(struct wlr_egl *egl,
 	attribs[atti++] = EGL_NONE;
 	assert(atti < sizeof(attribs)/sizeof(attribs[0]));
 
-	return eglCreateImageKHR(egl->display, EGL_NO_CONTEXT,
+	return egl->procs.eglCreateImageKHR(egl->display, EGL_NO_CONTEXT,
 		EGL_LINUX_DMA_BUF_EXT, NULL, attribs);
 }
 
@@ -551,7 +587,7 @@ static int get_egl_dmabuf_formats(struct wlr_egl *egl, int **formats) {
 	}
 
 	EGLint num;
-	if (!eglQueryDmaBufFormatsEXT(egl->display, 0, NULL, &num)) {
+	if (!egl->procs.eglQueryDmaBufFormatsEXT(egl->display, 0, NULL, &num)) {
 		wlr_log(WLR_ERROR, "Failed to query number of dmabuf formats");
 		return -1;
 	}
@@ -562,7 +598,7 @@ static int get_egl_dmabuf_formats(struct wlr_egl *egl, int **formats) {
 		return -1;
 	}
 
-	if (!eglQueryDmaBufFormatsEXT(egl->display, num, *formats, &num)) {
+	if (!egl->procs.eglQueryDmaBufFormatsEXT(egl->display, num, *formats, &num)) {
 		wlr_log(WLR_ERROR, "Failed to query dmabuf format");
 		free(*formats);
 		return -1;
@@ -582,7 +618,7 @@ static int get_egl_dmabuf_modifiers(struct wlr_egl *egl, int format,
 	}
 
 	EGLint num;
-	if (!eglQueryDmaBufModifiersEXT(egl->display, format, 0,
+	if (!egl->procs.eglQueryDmaBufModifiersEXT(egl->display, format, 0,
 			NULL, NULL, &num)) {
 		wlr_log(WLR_ERROR, "Failed to query dmabuf number of modifiers");
 		return -1;
@@ -598,7 +634,7 @@ static int get_egl_dmabuf_modifiers(struct wlr_egl *egl, int format,
 		return -1;
 	}
 
-	if (!eglQueryDmaBufModifiersEXT(egl->display, format, num,
+	if (!egl->procs.eglQueryDmaBufModifiersEXT(egl->display, format, num,
 		*modifiers, NULL, &num)) {
 		wlr_log(WLR_ERROR, "Failed to query dmabuf modifiers");
 		free(*modifiers);
@@ -621,7 +657,7 @@ bool wlr_egl_export_image_to_dmabuf(struct wlr_egl *egl, EGLImageKHR image,
 	}
 
 	// Only one set of modifiers is returned for all planes
-	if (!eglExportDMABUFImageQueryMESA(egl->display, image,
+	if (!egl->procs.eglExportDMABUFImageQueryMESA(egl->display, image,
 			(int *)&attribs->format, &attribs->n_planes, &attribs->modifier)) {
 		return false;
 	}
@@ -631,7 +667,7 @@ bool wlr_egl_export_image_to_dmabuf(struct wlr_egl *egl, EGLImageKHR image,
 		return false;
 	}
 
-	if (!eglExportDMABUFImageMESA(egl->display, image, attribs->fd,
+	if (!egl->procs.eglExportDMABUFImageMESA(egl->display, image, attribs->fd,
 			(EGLint *)attribs->stride, (EGLint *)attribs->offset)) {
 		return false;
 	}
diff --git a/render/glapi.txt b/render/glapi.txt
deleted file mode 100644
index b1166f27..00000000
--- a/render/glapi.txt
+++ /dev/null
@@ -1,19 +0,0 @@
-eglGetPlatformDisplayEXT
-eglCreatePlatformWindowSurfaceEXT
--eglCreateImageKHR
--eglDestroyImageKHR
--eglQueryWaylandBufferWL
--eglBindWaylandDisplayWL
--eglUnbindWaylandDisplayWL
--glEGLImageTargetTexture2DOES
--eglSwapBuffersWithDamageEXT
--eglSwapBuffersWithDamageKHR
--eglQueryDmaBufFormatsEXT
--eglQueryDmaBufModifiersEXT
--eglExportDMABUFImageQueryMESA
--eglExportDMABUFImageMESA
--eglDebugMessageControlKHR
--glDebugMessageCallbackKHR
--glDebugMessageControlKHR
--glPopDebugGroupKHR
--glPushDebugGroupKHR
diff --git a/render/gles2/renderer.c b/render/gles2/renderer.c
index 8bef5137..b5855d4e 100644
--- a/render/gles2/renderer.c
+++ b/render/gles2/renderer.c
@@ -11,9 +11,10 @@
 #include <wlr/render/wlr_renderer.h>
 #include <wlr/types/wlr_matrix.h>
 #include <wlr/util/log.h>
-#include "glapi.h"
 #include "render/gles2.h"
 
+struct wlr_gles2_procs gles2_procs = {0};
+
 static const struct wlr_renderer_impl renderer_impl;
 
 static struct wlr_gles2_renderer *gles2_get_renderer(
@@ -219,13 +220,13 @@ static bool gles2_resource_is_wl_drm_buffer(struct wlr_renderer *wlr_renderer,
 		struct wl_resource *resource) {
 	struct wlr_gles2_renderer *renderer = gles2_get_renderer(wlr_renderer);
 
-	if (!eglQueryWaylandBufferWL) {
+	if (!renderer->egl->exts.bind_wayland_display_wl) {
 		return false;
 	}
 
 	EGLint fmt;
-	return eglQueryWaylandBufferWL(renderer->egl->display, resource,
-		EGL_TEXTURE_FORMAT, &fmt);
+	return renderer->egl->procs.eglQueryWaylandBufferWL(renderer->egl->display,
+		resource, EGL_TEXTURE_FORMAT, &fmt);
 }
 
 static void gles2_wl_drm_buffer_get_size(struct wlr_renderer *wlr_renderer,
@@ -233,12 +234,14 @@ static void gles2_wl_drm_buffer_get_size(struct wlr_renderer *wlr_renderer,
 	struct wlr_gles2_renderer *renderer =
 		gles2_get_renderer(wlr_renderer);
 
-	if (!eglQueryWaylandBufferWL) {
+	if (!renderer->egl->exts.bind_wayland_display_wl) {
 		return;
 	}
 
-	eglQueryWaylandBufferWL(renderer->egl->display, buffer, EGL_WIDTH, width);
-	eglQueryWaylandBufferWL(renderer->egl->display, buffer, EGL_HEIGHT, height);
+	renderer->egl->procs.eglQueryWaylandBufferWL(renderer->egl->display,
+		buffer, EGL_WIDTH, width);
+	renderer->egl->procs.eglQueryWaylandBufferWL(renderer->egl->display,
+		buffer, EGL_HEIGHT, height);
 }
 
 static const struct wlr_drm_format_set *gles2_get_dmabuf_formats(
@@ -376,7 +379,7 @@ static void gles2_destroy(struct wlr_renderer *wlr_renderer) {
 
 	if (renderer->exts.debug_khr) {
 		glDisable(GL_DEBUG_OUTPUT_KHR);
-		glDebugMessageCallbackKHR(NULL, NULL);
+		gles2_procs.glDebugMessageCallbackKHR(NULL, NULL);
 	}
 
 	free(renderer);
@@ -405,19 +408,19 @@ static const struct wlr_renderer_impl renderer_impl = {
 };
 
 void push_gles2_marker(const char *file, const char *func) {
-	if (!glPushDebugGroupKHR) {
+	if (!gles2_procs.glPushDebugGroupKHR) {
 		return;
 	}
 
 	int len = snprintf(NULL, 0, "%s:%s", file, func) + 1;
 	char str[len];
 	snprintf(str, len, "%s:%s", file, func);
-	glPushDebugGroupKHR(GL_DEBUG_SOURCE_APPLICATION_KHR, 1, -1, str);
+	gles2_procs.glPushDebugGroupKHR(GL_DEBUG_SOURCE_APPLICATION_KHR, 1, -1, str);
 }
 
 void pop_gles2_marker(void) {
-	if (glPopDebugGroupKHR) {
-		glPopDebugGroupKHR();
+	if (gles2_procs.glPopDebugGroupKHR) {
+		gles2_procs.glPopDebugGroupKHR();
 	}
 }
 
@@ -516,6 +519,15 @@ static bool check_gl_ext(const char *exts, const char *ext) {
 	return false;
 }
 
+static void load_gl_proc(void *proc_ptr, const char *name) {
+	void *proc = (void *)eglGetProcAddress(name);
+	if (proc == NULL) {
+		wlr_log(WLR_ERROR, "eglGetProcAddress(%s) failed", name);
+		abort();
+	}
+	*(void **)proc_ptr = proc;
+}
+
 extern const GLchar quad_vertex_src[];
 extern const GLchar quad_fragment_src[];
 extern const GLchar ellipse_fragment_src[];
@@ -525,7 +537,9 @@ extern const GLchar tex_fragment_src_rgbx[];
 extern const GLchar tex_fragment_src_external[];
 
 struct wlr_renderer *wlr_gles2_renderer_create(struct wlr_egl *egl) {
-	if (!load_glapi()) {
+	const char *exts_str = (const char *)glGetString(GL_EXTENSIONS);
+	if (exts_str == NULL) {
+		wlr_log(WLR_ERROR, "Failed to get GL_EXTENSIONS");
 		return NULL;
 	}
 
@@ -542,37 +556,44 @@ struct wlr_renderer *wlr_gles2_renderer_create(struct wlr_egl *egl) {
 		return NULL;
 	}
 
-	renderer->exts_str = (const char *)glGetString(GL_EXTENSIONS);
 	wlr_log(WLR_INFO, "Using %s", glGetString(GL_VERSION));
 	wlr_log(WLR_INFO, "GL vendor: %s", glGetString(GL_VENDOR));
 	wlr_log(WLR_INFO, "GL renderer: %s", glGetString(GL_RENDERER));
-	wlr_log(WLR_INFO, "Supported GLES2 extensions: %s", renderer->exts_str);
+	wlr_log(WLR_INFO, "Supported GLES2 extensions: %s", exts_str);
 
-	if (!check_gl_ext(renderer->exts_str, "GL_EXT_texture_format_BGRA8888")) {
+	if (!check_gl_ext(exts_str, "GL_EXT_texture_format_BGRA8888")) {
 		wlr_log(WLR_ERROR, "BGRA8888 format not supported by GLES2");
 		free(renderer);
 		return NULL;
 	}
 
 	renderer->exts.read_format_bgra_ext =
-		check_gl_ext(renderer->exts_str, "GL_EXT_read_format_bgra");
-	renderer->exts.debug_khr =
-		check_gl_ext(renderer->exts_str, "GL_KHR_debug") &&
-		glDebugMessageCallbackKHR && glDebugMessageControlKHR;
-	renderer->exts.egl_image_external_oes =
-		check_gl_ext(renderer->exts_str, "GL_OES_EGL_image_external") &&
-		glEGLImageTargetTexture2DOES;
+		check_gl_ext(exts_str, "GL_EXT_read_format_bgra");
+
+	if (check_gl_ext(exts_str, "GL_KHR_debug")) {
+		renderer->exts.debug_khr = true;
+		load_gl_proc(&gles2_procs.glDebugMessageCallbackKHR,
+			"glDebugMessageCallbackKHR");
+		load_gl_proc(&gles2_procs.glDebugMessageControlKHR,
+			"glDebugMessageControlKHR");
+	}
+
+	if (check_gl_ext(exts_str, "GL_OES_EGL_image_external")) {
+		renderer->exts.egl_image_external_oes = true;
+		load_gl_proc(&gles2_procs.glEGLImageTargetTexture2DOES,
+			"glEGLImageTargetTexture2DOES");
+	}
 
 	if (renderer->exts.debug_khr) {
 		glEnable(GL_DEBUG_OUTPUT_KHR);
 		glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS_KHR);
-		glDebugMessageCallbackKHR(gles2_log, NULL);
+		gles2_procs.glDebugMessageCallbackKHR(gles2_log, NULL);
 
 		// Silence unwanted message types
-		glDebugMessageControlKHR(GL_DONT_CARE, GL_DEBUG_TYPE_POP_GROUP_KHR,
-			GL_DONT_CARE, 0, NULL, GL_FALSE);
-		glDebugMessageControlKHR(GL_DONT_CARE, GL_DEBUG_TYPE_PUSH_GROUP_KHR,
-			GL_DONT_CARE, 0, NULL, GL_FALSE);
+		gles2_procs.glDebugMessageControlKHR(GL_DONT_CARE,
+			GL_DEBUG_TYPE_POP_GROUP_KHR, GL_DONT_CARE, 0, NULL, GL_FALSE);
+		gles2_procs.glDebugMessageControlKHR(GL_DONT_CARE,
+			GL_DEBUG_TYPE_PUSH_GROUP_KHR, GL_DONT_CARE, 0, NULL, GL_FALSE);
 	}
 
 	PUSH_GLES2_DEBUG;
@@ -641,7 +662,7 @@ error:
 
 	if (renderer->exts.debug_khr) {
 		glDisable(GL_DEBUG_OUTPUT_KHR);
-		glDebugMessageCallbackKHR(NULL, NULL);
+		gles2_procs.glDebugMessageCallbackKHR(NULL, NULL);
 	}
 
 	free(renderer);
diff --git a/render/gles2/texture.c b/render/gles2/texture.c
index 9ff88b35..7beb0672 100644
--- a/render/gles2/texture.c
+++ b/render/gles2/texture.c
@@ -11,7 +11,6 @@
 #include <wlr/render/wlr_texture.h>
 #include <wlr/types/wlr_matrix.h>
 #include <wlr/util/log.h>
-#include "glapi.h"
 #include "render/gles2.h"
 #include "util/signal.h"
 
@@ -91,12 +90,12 @@ static bool gles2_texture_to_dmabuf(struct wlr_texture *wlr_texture,
 	if (!texture->image) {
 		assert(texture->target == GL_TEXTURE_2D);
 
-		if (!eglCreateImageKHR) {
+		if (!texture->egl->exts.image_base_khr) {
 			return false;
 		}
 
-		texture->image = eglCreateImageKHR(texture->egl->display,
-			texture->egl->context, EGL_GL_TEXTURE_2D_KHR,
+		texture->image = texture->egl->procs.eglCreateImageKHR(
+			texture->egl->display, texture->egl->context, EGL_GL_TEXTURE_2D_KHR,
 			(EGLClientBuffer)(uintptr_t)texture->tex, NULL);
 		if (texture->image == EGL_NO_IMAGE_KHR) {
 			return false;
@@ -188,7 +187,7 @@ struct wlr_texture *wlr_gles2_texture_from_wl_drm(struct wlr_egl *egl,
 		wlr_egl_make_current(egl, EGL_NO_SURFACE, NULL);
 	}
 
-	if (!glEGLImageTargetTexture2DOES) {
+	if (!gles2_procs.glEGLImageTargetTexture2DOES) {
 		return NULL;
 	}
 
@@ -230,7 +229,8 @@ struct wlr_texture *wlr_gles2_texture_from_wl_drm(struct wlr_egl *egl,
 
 	glGenTextures(1, &texture->tex);
 	glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture->tex);
-	glEGLImageTargetTexture2DOES(GL_TEXTURE_EXTERNAL_OES, texture->image);
+	gles2_procs.glEGLImageTargetTexture2DOES(GL_TEXTURE_EXTERNAL_OES,
+		texture->image);
 
 	POP_GLES2_DEBUG;
 	return &texture->wlr_texture;
@@ -242,7 +242,7 @@ struct wlr_texture *wlr_gles2_texture_from_dmabuf(struct wlr_egl *egl,
 		wlr_egl_make_current(egl, EGL_NO_SURFACE, NULL);
 	}
 
-	if (!glEGLImageTargetTexture2DOES) {
+	if (!gles2_procs.glEGLImageTargetTexture2DOES) {
 		return NULL;
 	}
 
@@ -290,7 +290,8 @@ struct wlr_texture *wlr_gles2_texture_from_dmabuf(struct wlr_egl *egl,
 
 	glGenTextures(1, &texture->tex);
 	glBindTexture(GL_TEXTURE_EXTERNAL_OES, texture->tex);
-	glEGLImageTargetTexture2DOES(GL_TEXTURE_EXTERNAL_OES, texture->image);
+	gles2_procs.glEGLImageTargetTexture2DOES(GL_TEXTURE_EXTERNAL_OES,
+		texture->image);
 
 	POP_GLES2_DEBUG;
 	return &texture->wlr_texture;
diff --git a/render/meson.build b/render/meson.build
index 87577aba..79daba93 100644
--- a/render/meson.build
+++ b/render/meson.build
@@ -1,12 +1,3 @@
-glgen = find_program('../glgen.sh')
-
-glapi = custom_target(
-	'glapi',
-	input: 'glapi.txt',
-	output: ['@BASENAME@.c', '@BASENAME@.h'],
-	command: [glgen, '@INPUT@', '@OUTDIR@'],
-)
-
 lib_wlr_render = static_library(
 	'wlr_render',
 	files(
@@ -20,7 +11,6 @@ lib_wlr_render = static_library(
 		'wlr_renderer.c',
 		'wlr_texture.c',
 	),
-	glapi,
 	include_directories: wlr_inc,
 	dependencies: [
 		egl,
@@ -33,5 +23,4 @@ lib_wlr_render = static_library(
 
 wlr_render = declare_dependency(
 	link_with: lib_wlr_render,
-	sources: glapi[1],
 )