Audit logging statements
I should audit each use of g_tls_log_debug() to make sure the debug message makes sense. E.g.
g_tls_log_debug (tls, "TLS handshake thread failed: claiming op failed");
Maybe something about "op in progress" would be more descriptive. Or:
g_tls_log_debug (tls, "TLS handshake thread failed: %s", error ? error->message : "no error");
Printing "no error" on failure is not great.