From 85fe9484945cb57ffd49df248b0e5057eba6af04 Mon Sep 17 00:00:00 2001 From: Benjamin Franzke Date: Tue, 9 Aug 2011 14:23:18 +0200 Subject: [PATCH] egl: Native Display autodetection MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit EGL doesnt define howto manage different native platforms. So mesa has a builtime configurable default platform, whith non-standard envvar (EGL_PLATFORM) overwrites. This caused unneeded bugreports, when EGL_PLATFORM was forgotten. Detection is grouped into basic types of NativeDisplays (which itself needs to be detected). The final decision is based on characteristcs of these basic types: File Desciptor based platforms (fbdev): - fstat(2) to check for being a fd that belongs to a character device - check kernel subsystem (todo) Pointer to structuctures (x11, wayland, drm/gbm): - mincore(2) to check whether its valid pointer to some memory. - magic elements (e.g. pointers to exported symbols): o wayland display stores interface type pointer (first elm.) o gbm stores pointer to its constructor (first elm.) o x11 as a fallback (FIXME?) Reviewed-by: Kristian Høgsberg --- configure.ac | 2 + src/egl/main/Makefile | 13 +++++ src/egl/main/eglapi.c | 8 +-- src/egl/main/egldisplay.c | 100 ++++++++++++++++++++++++++++++++++++-- src/egl/main/egldisplay.h | 2 +- 5 files changed, 117 insertions(+), 8 deletions(-) diff --git a/configure.ac b/configure.ac index 1b1823a211f..9195da9b3a3 100644 --- a/configure.ac +++ b/configure.ac @@ -1370,6 +1370,8 @@ if test "x$enable_egl" = xyes; then EGL_LIB_DEPS="$DLOPEN_LIBS $SELINUX_LIBS -lpthread" EGL_DRIVERS_DIRS="" + AC_CHECK_FUNC(mincore, [DEFINES="$DEFINES -DHAVE_MINCORE"]) + if test "$enable_static" != yes; then # build egl_glx when libGL is built if test "x$enable_glx" = xyes; then diff --git a/src/egl/main/Makefile b/src/egl/main/Makefile index 775fbbe178b..c100fbfeb9c 100644 --- a/src/egl/main/Makefile +++ b/src/egl/main/Makefile @@ -93,6 +93,19 @@ ifeq ($(firstword $(EGL_PLATFORMS)),fbdev) EGL_NATIVE_PLATFORM=_EGL_PLATFORM_FBDEV endif +ifneq ($(findstring x11, $(EGL_PLATFORMS)),) +LOCAL_CFLAGS += -DHAVE_X11_PLATFORM +endif +ifneq ($(findstring wayland, $(EGL_PLATFORMS)),) +LOCAL_CFLAGS += -DHAVE_WAYLAND_PLATFORM +endif +ifneq ($(findstring drm, $(EGL_PLATFORMS)),) +LOCAL_CFLAGS += -DHAVE_DRM_PLATFORM +endif +ifneq ($(findstring fbdev, $(EGL_PLATFORMS)),) +LOCAL_CFLAGS += -DHAVE_FBDEV_PLATFORM +endif + LOCAL_CFLAGS += \ -D_EGL_NATIVE_PLATFORM=$(EGL_NATIVE_PLATFORM) \ -D_EGL_DRIVER_SEARCH_DIR=\"$(EGL_DRIVER_INSTALL_DIR)\" diff --git a/src/egl/main/eglapi.c b/src/egl/main/eglapi.c index 0ba7794e2c9..5d186c60e5a 100644 --- a/src/egl/main/eglapi.c +++ b/src/egl/main/eglapi.c @@ -301,7 +301,7 @@ _eglUnlockDisplay(_EGLDisplay *dpy) EGLDisplay EGLAPIENTRY eglGetDisplay(EGLNativeDisplayType nativeDisplay) { - _EGLPlatformType plat = _eglGetNativePlatform(); + _EGLPlatformType plat = _eglGetNativePlatform(nativeDisplay); _EGLDisplay *dpy = _eglFindDisplay(plat, (void *) nativeDisplay); return _eglGetDisplayHandle(dpy); } @@ -538,7 +538,7 @@ eglCreateWindowSurface(EGLDisplay dpy, EGLConfig config, EGLSurface ret; _EGL_CHECK_CONFIG(disp, conf, EGL_NO_SURFACE, drv); - if (disp->Platform != _eglGetNativePlatform()) + if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay)) RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_WINDOW, EGL_NO_SURFACE); surf = drv->API.CreateWindowSurface(drv, disp, conf, window, attrib_list); @@ -559,7 +559,7 @@ eglCreatePixmapSurface(EGLDisplay dpy, EGLConfig config, EGLSurface ret; _EGL_CHECK_CONFIG(disp, conf, EGL_NO_SURFACE, drv); - if (disp->Platform != _eglGetNativePlatform()) + if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay)) RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_PIXMAP, EGL_NO_SURFACE); surf = drv->API.CreatePixmapSurface(drv, disp, conf, pixmap, attrib_list); @@ -720,7 +720,7 @@ eglCopyBuffers(EGLDisplay dpy, EGLSurface surface, EGLNativePixmapType target) EGLBoolean ret; _EGL_CHECK_SURFACE(disp, surf, EGL_FALSE, drv); - if (disp->Platform != _eglGetNativePlatform()) + if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay)) RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_PIXMAP, EGL_FALSE); ret = drv->API.CopyBuffers(drv, disp, surf, target); diff --git a/src/egl/main/egldisplay.c b/src/egl/main/egldisplay.c index 60f31777272..2849dd96c64 100644 --- a/src/egl/main/egldisplay.c +++ b/src/egl/main/egldisplay.c @@ -43,6 +43,23 @@ #include "eglmutex.h" #include "egllog.h" +/* Includes for _eglNativePlatformDetectNativeDisplay */ +#ifdef HAVE_MINCORE +#include +#include +#endif +#ifdef HAVE_WAYLAND_PLATFORM +#include +#endif +#ifdef HAVE_DRM_PLATFORM +#include +#endif +#ifdef HAVE_FBDEV_PLATFORM +#include +#include +#include +#endif + /** * Return the native platform by parsing EGL_PLATFORM. @@ -83,18 +100,95 @@ _eglGetNativePlatformFromEnv(void) } +/** + * Perform validity checks on a generic pointer. + */ +static EGLBoolean +_eglPointerIsDereferencable(void *p) +{ +#ifdef HAVE_MINCORE + uintptr_t addr = (uintptr_t) p; + unsigned char valid = 0; + const long page_size = getpagesize(); + + if (p == NULL) + return EGL_FALSE; + + /* align addr to page_size */ + addr &= ~(page_size - 1); + + if (mincore((void *) addr, page_size, &valid) < 0) { + _eglLog(_EGL_DEBUG, "mincore failed: %m"); + return EGL_FALSE; + } + + return (valid & 0x01) == 0x01; +#else + return p != NULL; +#endif +} + + +/** + * Try detecting native platform with the help of native display characteristcs. + */ +static _EGLPlatformType +_eglNativePlatformDetectNativeDisplay(EGLNativeDisplayType nativeDisplay) +{ +#ifdef HAVE_FBDEV_PLATFORM + struct stat buf; +#endif + + if (nativeDisplay == EGL_DEFAULT_DISPLAY) + return _EGL_INVALID_PLATFORM; + +#ifdef HAVE_FBDEV_PLATFORM + /* fbdev is the only platform that can be a file descriptor. */ + if (fstat((intptr_t) nativeDisplay, &buf) == 0 && S_ISCHR(buf.st_mode)) + return _EGL_PLATFORM_FBDEV; +#endif + + if (_eglPointerIsDereferencable(nativeDisplay)) { + void *first_pointer = *(void **) nativeDisplay; + +#ifdef HAVE_WAYLAND_PLATFORM + /* wl_display is a wl_proxy, which is a wl_object. + * wl_object's first element points to the interfacetype. */ + if (first_pointer == &wl_display_interface) + return _EGL_PLATFORM_WAYLAND; +#endif + +#ifdef HAVE_DRM_PLATFORM + /* gbm has a pointer to its constructor as first element. */ + if (first_pointer == gbm_create_device) + return _EGL_PLATFORM_DRM; +#endif + +#ifdef HAVE_X11_PLATFORM + /* If not matched to any other platform, fallback to x11. */ + return _EGL_PLATFORM_X11; +#endif + } + + return _EGL_INVALID_PLATFORM; +} + + /** * Return the native platform. It is the platform of the EGL native types. */ _EGLPlatformType -_eglGetNativePlatform(void) +_eglGetNativePlatform(EGLNativeDisplayType nativeDisplay) { static _EGLPlatformType native_platform = _EGL_INVALID_PLATFORM; if (native_platform == _EGL_INVALID_PLATFORM) { native_platform = _eglGetNativePlatformFromEnv(); - if (native_platform == _EGL_INVALID_PLATFORM) - native_platform = _EGL_NATIVE_PLATFORM; + if (native_platform == _EGL_INVALID_PLATFORM) { + native_platform = _eglNativePlatformDetectNativeDisplay(nativeDisplay); + if (native_platform == _EGL_INVALID_PLATFORM) + native_platform = _EGL_NATIVE_PLATFORM; + } } return native_platform; diff --git a/src/egl/main/egldisplay.h b/src/egl/main/egldisplay.h index 9cd4dbfcc8a..05335ada63c 100644 --- a/src/egl/main/egldisplay.h +++ b/src/egl/main/egldisplay.h @@ -150,7 +150,7 @@ struct _egl_display extern _EGLPlatformType -_eglGetNativePlatform(void); +_eglGetNativePlatform(EGLNativeDisplayType nativeDisplay); extern void -- 2.30.2