+ print r'''
+
+
+/*
+ * Handle to the true libGL.so
+ */
+static void *libgl_handle = NULL;
+
+
+/*
+ * Invoke the true dlopen() function.
+ */
+static void *__dlopen(const char *filename, int flag)
+{
+ typedef void * (*PFNDLOPEN)(const char *, int);
+ static PFNDLOPEN dlopen_ptr = NULL;
+
+ if (!dlopen_ptr) {
+ dlopen_ptr = (PFNDLOPEN)dlsym(RTLD_NEXT, "dlopen");
+ if (!dlopen_ptr) {
+ OS::DebugMessage("apitrace: error: dlsym(RTLD_NEXT, \"dlopen\") failed\n");
+ return NULL;
+ }
+ }
+
+ return dlopen_ptr(filename, flag);
+}
+
+
+/*
+ * Several applications, such as Quake3, use dlopen("libGL.so.1"), but
+ * LD_PRELOAD does not intercept symbols obtained via dlopen/dlsym, therefore
+ * we need to intercept the dlopen() call here, and redirect to our wrapper
+ * shared object.
+ */
+extern "C" PUBLIC
+void * dlopen(const char *filename, int flag)
+{
+ void *handle;
+
+ handle = __dlopen(filename, flag);
+
+ const char * libgl_filename = getenv("TRACE_LIBGL");
+
+ if (filename && handle && !libgl_filename) {
+ if (0) {
+ OS::DebugMessage("apitrace: warning: dlopen(\"%s\", 0x%x)\n", filename, flag);
+ }
+
+ // FIXME: handle absolute paths and other versions
+ if (strcmp(filename, "libGL.so") == 0 ||
+ strcmp(filename, "libGL.so.1") == 0) {
+
+ // Use the true libGL.so handle instead of RTLD_NEXT from now on
+ libgl_handle = handle;
+
+ // Get the file path for our shared object, and use it instead
+ static int dummy = 0xdeedbeef;
+ Dl_info info;
+ if (dladdr(&dummy, &info)) {
+ OS::DebugMessage("apitrace: redirecting dlopen(\"%s\", 0x%x)\n", filename, flag);
+ handle = __dlopen(info.dli_fname, flag);
+ } else {
+ OS::DebugMessage("apitrace: warning: dladdr() failed\n");
+ }
+ }
+ }
+
+ return handle;
+}
+
+
+/*
+ * Lookup a libGL symbol
+ */
+void * __libgl_sym(const char *symbol)
+{
+ void *result;
+
+ if (!libgl_handle) {
+ /*
+ * The app doesn't directly link against libGL.so, nor does it directly
+ * dlopen it. So we have to load it ourselves.
+ */
+
+ const char * libgl_filename = getenv("TRACE_LIBGL");
+
+ if (!libgl_filename) {
+ /*
+ * Try to use whatever libGL.so the library is linked against.
+ */
+
+ result = dlsym(RTLD_NEXT, symbol);
+ if (result) {
+ libgl_handle = RTLD_NEXT;
+ return result;
+ }
+
+ libgl_filename = "libGL.so.1";
+ }
+
+ /*
+ * It would have been preferable to use RTLD_LOCAL to ensure that the
+ * application can never access libGL.so symbols directly, but this
+ * won't work, given libGL.so often loads a driver specific SO and
+ * exposes symbols to it.
+ */
+
+ libgl_handle = __dlopen(libgl_filename, RTLD_GLOBAL | RTLD_LAZY);
+ if (!libgl_handle) {
+ OS::DebugMessage("apitrace: error: couldn't find libGL.so\n");
+ return NULL;
+ }
+ }
+
+ return dlsym(libgl_handle, symbol);
+}
+
+
+'''