1 files changed, 53 insertions, 0 deletions
diff --git a/include/osmocom/msc/csd_filter.h b/include/osmocom/msc/csd_filter.h
new file mode 100644
index 000000000..51ffff706
--- /dev/null
+++ b/include/osmocom/msc/csd_filter.h
@@ -0,0 +1,53 @@
+/* Filter/overlay data rates for CSD, across MS, RAN and CN limitations */
+/*
+ * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Oliver Smith
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#pragma once
+
+#include <osmocom/gsm/gsm_utils.h>
+#include <osmocom/gsm/mncc.h>
+#include <osmocom/mgcp_client/mgcp_client.h>
+
+#include <osmocom/msc/csd_bs.h>
+#include <osmocom/msc/sdp_msg.h>
+
+/* Combine various data rate selections to obtain a resulting set allowed by
+ * all of them. Members reflect the different entities/stages that select data
+ * rates in CSD. Call csd_filter_run() and obtain the resulting set in
+ * csd_filter.result. */
+struct csd_filter {
+	/* The fixed set available on the RAN type, per definition. */
+	struct csd_bs_list ran;
+	/* The services advertised by the MS Bearer Capabilities */
+	struct csd_bs_list ms;
+	/* If known, the set the current RAN cell allows / has available. This
+	 * may not be available if the BSC does not issue this information
+	 * early enough. Should be ignored if empty. */
+	struct csd_bs_list bss;
+
+	/* After a channel was assigned, this reflects the chosen BS. */
+	enum csd_bs assignment;
+};
+
+void csd_filter_set_ran(struct csd_filter *filter, enum osmo_rat_type ran_type);
+int csd_filter_run(struct csd_filter *filter, struct sdp_msg *result, const struct sdp_msg *remote);
+
+int csd_filter_to_str_buf(char *buf, size_t buflen, const struct csd_filter *filter,
+			    const struct sdp_msg *result, const struct sdp_msg *remote);
+char *csd_filter_to_str_c(void *ctx, const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote);
+const char *csd_filter_to_str(const struct csd_filter *filter, const struct sdp_msg *result, const struct sdp_msg *remote);