+ * Set the function to be called when there is a message to log.
+ * Note that the function will be called with an internal lock held.
+ * Recursive logging is not allowed.
+ */
+void
+_eglSetLogProc(_EGLLogProc logger)
+{
+ EGLint num_messages = 0;
+
+ _eglLockMutex(&logging.mutex);
+
+ if (logging.logger != logger) {
+ logging.logger = logger;
+
+ num_messages = logging.num_messages;
+ logging.num_messages = 0;
+ }
+
+ _eglUnlockMutex(&logging.mutex);
+
+ if (num_messages)
+ _eglLog(_EGL_DEBUG,
+ "New logger installed. "
+ "Messages before the new logger might not be available.");
+}
+
+
+/**
+ * Set the log reporting level.
+ */
+void
+_eglSetLogLevel(EGLint level)
+{
+ switch (level) {
+ case _EGL_FATAL:
+ case _EGL_WARNING:
+ case _EGL_INFO:
+ case _EGL_DEBUG:
+ _eglLockMutex(&logging.mutex);
+ logging.level = level;
+ _eglUnlockMutex(&logging.mutex);
+ break;
+ default:
+ break;
+ }
+}
+
+
+/**
+ * The default logger. It prints the message to stderr.
+ */
+static void
+_eglDefaultLogger(EGLint level, const char *msg)
+{
+ fprintf(stderr, "libEGL %s: %s\n", level_strings[level], msg);
+}
+
+
+/**
+ * Initialize the logging facility.
+ */
+static void
+_eglInitLogger(void)
+{
+ const char *log_env;
+ EGLint i, level = -1;
+
+ if (logging.initialized)
+ return;
+
+ log_env = getenv("EGL_LOG_LEVEL");
+ if (log_env) {
+ for (i = 0; level_strings[i]; i++) {
+ if (_eglstrcasecmp(log_env, level_strings[i]) == 0) {
+ level = i;
+ break;
+ }
+ }
+ }
+ else {
+ level = FALLBACK_LOG_LEVEL;
+ }
+
+ logging.logger = _eglDefaultLogger;
+ logging.level = (level >= 0) ? level : FALLBACK_LOG_LEVEL;
+ logging.initialized = EGL_TRUE;
+
+ /* it is fine to call _eglLog now */
+ if (log_env && level < 0) {
+ _eglLog(_EGL_WARNING,
+ "Unrecognized EGL_LOG_LEVEL environment variable value. "
+ "Expected one of \"fatal\", \"warning\", \"info\", \"debug\". "
+ "Got \"%s\". Falling back to \"%s\".",
+ log_env, level_strings[FALLBACK_LOG_LEVEL]);
+ }
+}
+
+
+/**
+ * Log a message with message logger.