+static int irmp_lib_initialized;
+static size_t irmp_lib_client_id;
+static GMutex irmp_lib_mutex;
+
+struct irmp_instance {
+ size_t client_id;
+ GMutex *mutex;
+};
+
+static void irmp_lib_autoinit(void)
+{
+ if (irmp_lib_initialized)
+ return;
+
+ irmp_lib_client_id = 0;
+ g_mutex_init(&irmp_lib_mutex);
+
+ irmp_lib_initialized = 1;
+}
+
+static size_t irmp_next_client_id(void)
+{
+ size_t id;
+
+ do {
+ id = ++irmp_lib_client_id;
+ } while (!id);
+
+ return id;
+}
+
+IRMP_DLLEXPORT struct irmp_instance *irmp_instance_alloc(void)
+{
+ struct irmp_instance *inst;
+
+ irmp_lib_autoinit();
+
+ inst = g_malloc0(sizeof(*inst));
+ if (!inst)
+ return NULL;
+
+ inst->client_id = irmp_next_client_id();
+ inst->mutex = &irmp_lib_mutex;
+
+ return inst;
+}
+
+IRMP_DLLEXPORT void irmp_instance_free(struct irmp_instance *state)
+{
+
+ irmp_lib_autoinit();
+
+ if (!state)
+ return;
+
+ g_free(state);
+}
+
+IRMP_DLLEXPORT size_t irmp_instance_id(struct irmp_instance *state)
+{
+
+ irmp_lib_autoinit();
+
+ return state ? state->client_id : 0;
+}
+
+IRMP_DLLEXPORT int irmp_instance_lock(struct irmp_instance *state, int wait)
+{
+ int rc;
+ PyGILState_STATE pyst;
+
+ irmp_lib_autoinit();
+
+ if (!state || !state->mutex)
+ return -EINVAL;
+
+ pyst = PyGILState_Ensure();
+ Py_BEGIN_ALLOW_THREADS
+ if (wait) {
+ g_mutex_lock(state->mutex);
+ rc = 0;
+ } else {
+ rc = g_mutex_trylock(state->mutex);
+ }
+ Py_END_ALLOW_THREADS
+ PyGILState_Release(pyst);
+ if (rc != 0)
+ return rc;
+
+ return 0;
+}
+
+IRMP_DLLEXPORT void irmp_instance_unlock(struct irmp_instance *state)
+{
+
+ irmp_lib_autoinit();
+
+ if (!state || !state->mutex)
+ return;
+
+ g_mutex_unlock(state->mutex);
+}
+