#if defined(_WIN32)
HINSTANCE __libGlHandle = NULL;
#else
-void *__libGlHandle = RTLD_NEXT;
+void *__libGlHandle = NULL;
#endif
#else
/*
- * Lookup a EGL or GLES symbol
+ * Lookup a public EGL/GL/GLES symbol
+ *
+ * The spec states that eglGetProcAddress should only be used for non-core
+ * (extensions) entry-points. Core entry-points should be taken directly from
+ * the API specific libraries.
+ *
+ * We cannot tell here which API a symbol is meant for here (as some are
+ * exported by many). So this code assumes that the appropriate shared
+ * libraries have been loaded previously (either dlopened with RTLD_GLOBAL, or
+ * as part of the executable dependencies), and that their symbols available
+ * for quering via dlsym(RTLD_NEXT, ...).
*/
-static inline void *
-__libegl_sym(const char *symbol)
-{
- void *proc;
-
- /* Always try dlsym before eglGetProcAddress as spec 3.10 says
- * implementation may choose to also export extension functions
- * publicly.
- */
- proc = dlsym(__libGlHandle, symbol);
- if (!proc && symbol[0] == 'g' && symbol[1] == 'l')
- proc = (void *) __eglGetProcAddress(symbol);
-
- return proc;
-}
-
void *
__getPublicProcAddress(const char *procName)
{
- return __libegl_sym(procName);
+ return dlsym(RTLD_NEXT, procName);
}
+/*
+ * Lookup a private EGL/GL/GLES symbol
+ *
+ * Private symbols should always be available through eglGetProcAddress, and
+ * they are guaranteed to work with any context bound (regardless of the API).
+ *
+ * However, per issue#57, eglGetProcAddress returns garbage on some
+ * implementations, and the spec states that implementations may choose to also
+ * export extension functions publicly, so we always attempt dlsym before
+ * eglGetProcAddress to mitigate that.
+ */
void *
__getPrivateProcAddress(const char *procName)
{
- return __libegl_sym(procName);
+ void *proc;
+ proc = dlsym(RTLD_NEXT, procName);
+ if (!proc && procName[0] == 'g' && procName[1] == 'l')
+ proc = (void *) __eglGetProcAddress(procName);
+
+ return proc;
}
#endif
}
};
+/**
+ * Load the symbols from the specified shared object into global namespace, so
+ * that they can be later found by dlsym(RTLD_NEXT, ...);
+ */
+static void
+load(const char *filename)
+{
+ if (!dlopen(filename, RTLD_GLOBAL | RTLD_LAZY)) {
+ std::cerr << "error: unable to open " << filename << "\n";
+ exit(1);
+ }
+}
+
void
init(void) {
+ load("libEGL.so.1");
+
display = XOpenDisplay(NULL);
if (!display) {
std::cerr << "error: unable to open display " << XDisplayName(NULL) << "\n";
screen = DefaultScreen(display);
- __libGlHandle = dlopen("libEGL.so", RTLD_GLOBAL | RTLD_LAZY);
- if (!__libGlHandle) {
- std::cerr << "error: unable to open libEGL.so\n";
- XCloseDisplay(display);
- exit(1);
- }
-
eglDisplay = eglGetDisplay(display);
if (eglDisplay == EGL_NO_DISPLAY) {
std::cerr << "error: unable to get EGL display\n";
switch (profile) {
case PROFILE_COMPAT:
+ load("libGL.so.1");
eglBindAPI(EGL_OPENGL_API);
break;
case PROFILE_ES1:
+ load("libGLESv1_CM.so.1");
eglBindAPI(EGL_OPENGL_ES_API);
break;
case PROFILE_ES2:
+ load("libGLESv2.so.1");
eglBindAPI(EGL_OPENGL_ES_API);
attribs.add(EGL_CONTEXT_CLIENT_VERSION, 2);
break;