handover_ctrl: add control interface for handover settings

The VTY handover_vtc.c offers a large number of handover specific
settings. Those settings are (with one exception) auto generated using
macros. Lets add an equivalent for the control interface that uses the
same auto generation mechanisms.

Change-Id: I12f143906818fd6b16e8783157cbb1eb51e49ffc
Depends: libosmocore I53fc207677f52b1dc748b01d58424839cdba807c
Related: SYS#5369

3 files changed, 221 insertions, 0 deletions

diff --git a/src/osmo-bsc/Makefile.am b/src/osmo-bsc/Makefile.am
index df4e0c350..840e956ab 100644
--- a/src/osmo-bsc/Makefile.am
+++ b/src/osmo-bsc/Makefile.am
@@ -61,6 +61,7 @@ osmo_bsc_SOURCES = \
 	gsm_04_08_rr.c \
 	gsm_data.c \
 	handover_cfg.c \
+	handover_ctrl.c \
 	handover_decision.c \
 	handover_decision_2.c \
 	handover_fsm.c \
diff --git a/src/osmo-bsc/handover_ctrl.c b/src/osmo-bsc/handover_ctrl.c
new file mode 100644
index 000000000..139d0382b
--- /dev/null
+++ b/src/osmo-bsc/handover_ctrl.c
@@ -0,0 +1,216 @@
+/* OsmoBSC handover control interface implementation */
+/* (C) 2021 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * Author: Philipp Maier <pmaier@sysmocom.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation; either version 3 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <stdbool.h>
+#include <talloc.h>
+#include <osmocom/bsc/vty.h>
+#include <osmocom/bsc/handover_cfg.h>
+#include <osmocom/bsc/gsm_data.h>
+#include <osmocom/bsc/bts.h>
+#include <osmocom/bsc/handover_decision_2.h>
+#include <osmocom/ctrl/control_cmd.h>
+
+/* In handover_cfg.h the config items are described in VTY syntax. To be able to
+ * use those here in the CTRL interface, we parse the config arguments like the
+ * VTY would. (the value specification may be in the form of "<from-to>" or
+ * "A|B|C|..." */
+static bool verify_vty_cmd_arg(void *ctx, const char *range, const char *value)
+{
+	bool success;
+	char *range_tok;
+	char *valid_val;
+
+	/* "default" value is always a valid value */
+	if (strcmp(value, "default") == 0)
+		return true;
+
+	/* Try to check for a range first since it is the most common case */
+	if (range[0] == '<') {
+		if (vty_cmd_range_match(range, value))
+			return true;
+		else
+			return false;
+	}
+
+	/* Try to tokenize the string to check for distintinct values */
+	success = false;
+	range_tok = talloc_zero_size(ctx, strlen(range) + 1);
+	memcpy(range_tok, range, strlen(range));
+	valid_val = strtok(range_tok, "|");
+	while (valid_val != NULL) {
+		if (strcmp(valid_val, value) == 0) {
+			success = true;
+			break;
+		}
+		valid_val = strtok(NULL, "|");
+	}
+
+	talloc_free(range_tok);
+	return success;
+}
+
+/* NOTE: The following macro scheme has been designed for using it in the VTY
+ * code. However, for the most part it also works for CTRL interface code as
+ * well. */
+#define HO_CFG_ONE_MEMBER(TYPE, NAME, DEFAULT_VAL, VTY_CMD_PREFIX, VTY_CMD, VTY_CMD_ARG, VTY_ARG_EVAL, VTY_WRITE_FMT, VTY_WRITE_CONV, VTY6) \
+CTRL_CMD_DEFINE(NAME, VTY_CMD_PREFIX VTY_CMD); \
+static int get_##NAME(struct ctrl_cmd *cmd, void *_data) \
+{ \
+	struct gsm_network *net = cmd->node; \
+	struct handover_cfg *ho = net->ho; \
+	TYPE val; \
+	if (ho_isset_##NAME(ho)) { \
+		val = ho_get_##NAME(ho); \
+		cmd->reply = talloc_asprintf(cmd, VTY_WRITE_FMT, VTY_WRITE_CONV(val)); \
+	} else \
+		cmd->reply = talloc_asprintf(cmd, "%s", #DEFAULT_VAL); \
+	return CTRL_CMD_REPLY; \
+} \
+static int set_##NAME(struct ctrl_cmd *cmd, void *_data) \
+{ \
+	struct gsm_network *net = cmd->node; \
+	struct handover_cfg *ho = net->ho; \
+	TYPE value; \
+	if (strcmp(cmd->value, "default") == 0) \
+		value = VTY_ARG_EVAL(#DEFAULT_VAL); \
+	else \
+		value = VTY_ARG_EVAL(cmd->value); \
+	ho_set_##NAME(ho, value); \
+	return get_##NAME(cmd, _data); \
+} \
+static int verify_##NAME(struct ctrl_cmd *cmd, const char *value, void *_data) \
+{ \
+	if (verify_vty_cmd_arg(cmd, VTY_CMD_ARG, value) != true) \
+		return -1; \
+	return 0; \
+} \
+CTRL_CMD_DEFINE(bts_##NAME, VTY_CMD_PREFIX VTY_CMD); \
+static int get_bts_##NAME(struct ctrl_cmd *cmd, void *_data) \
+{ \
+        struct gsm_bts *bts = cmd->node; \
+	struct handover_cfg *ho = bts->ho; \
+	TYPE val; \
+	if (ho_isset_##NAME(ho)) { \
+		val = ho_get_##NAME(ho); \
+		cmd->reply = talloc_asprintf(cmd, VTY_WRITE_FMT, VTY_WRITE_CONV(val)); \
+	} else { \
+		cmd->reply = talloc_asprintf(cmd, "%s", #DEFAULT_VAL); \
+	} \
+	return CTRL_CMD_REPLY; \
+} \
+static int set_bts_##NAME(struct ctrl_cmd *cmd, void *_data) \
+{ \
+	struct gsm_bts *bts = cmd->node; \
+	struct handover_cfg *ho = bts->ho; \
+	TYPE value; \
+	if (strcmp(cmd->value, "default") == 0) \
+		value = VTY_ARG_EVAL(#DEFAULT_VAL); \
+	else \
+		value = VTY_ARG_EVAL(cmd->value); \
+	ho_set_##NAME(ho, value); \
+	return get_bts_##NAME(cmd, _data); \
+} \
+static int verify_bts_##NAME(struct ctrl_cmd *cmd, const char *value, void *_data) \
+{ \
+	return verify_##NAME(cmd, value, _data); \
+} \
+
+/* Expand the above macro using the definitions from handover_cfg.h */
+HO_CFG_ALL_MEMBERS
+#undef HO_CFG_ONE_MEMBER
+
+CTRL_CMD_DEFINE(congestion_check_interval, "handover2 congestion-check");
+static int get_congestion_check_interval(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	if (net->hodec2.congestion_check_interval_s > 0)
+		cmd->reply = talloc_asprintf(cmd, "%u", net->hodec2.congestion_check_interval_s);
+	else
+		cmd->reply = "disabled";
+	return CTRL_CMD_REPLY;
+}
+
+static int set_congestion_check_interval(struct ctrl_cmd *cmd, void *_data)
+{
+	struct gsm_network *net = cmd->node;
+	int value;
+
+	/* Trigger congestion check and leave without changing anything */
+	if (strcmp(cmd->value, "now") == 0) {
+		hodec2_congestion_check(net);
+		return get_congestion_check_interval(cmd, _data);
+	}
+
+	if (strcmp(cmd->value, "disabled") == 0)
+		value = 0;
+	else
+		value = atoi(cmd->value);
+	hodec2_on_change_congestion_check_interval(net, value);
+	return get_congestion_check_interval(cmd, _data);
+}
+
+static int verify_congestion_check_interval(struct ctrl_cmd *cmd, const char *value, void *_data)
+{
+	if (strcmp(value, "disabled") == 0)
+		return 0;
+	if (strcmp(value, "now") == 0)
+		return 0;
+	if (verify_vty_cmd_arg(cmd, "<1-999>", value))
+		return 0;
+	return -1;
+}
+
+/* Filter name member in cmd for illegal '/' characters */
+static struct ctrl_cmd_element *filter_name(void *ctx,
+					    struct ctrl_cmd_element *cmd)
+{
+	unsigned int i;
+	char *name;
+
+	if (osmo_separated_identifiers_valid(cmd->name, " -"))
+		return cmd;
+
+	name = talloc_strdup(ctx, cmd->name);
+	for (i = 0; i < strlen(name); i++) {
+		if (name[i] == '/')
+			name[i] = '-';
+	}
+
+	cmd->name = name;
+	return cmd;
+}
+
+int bsc_ho_ctrl_cmds_install(void *ctx)
+{
+	int rc = 0;
+
+	rc |= ctrl_cmd_install(CTRL_NODE_ROOT, &cmd_congestion_check_interval);
+
+#define HO_CFG_ONE_MEMBER(TYPE, NAME, DEFAULT_VAL, VTY0, VTY1, VTY2, VTY_ARG_EVAL, VTY4, VTY5, VTY6) \
+	rc |= ctrl_cmd_install(CTRL_NODE_ROOT, filter_name(ctx, &cmd_##NAME)); \
+	rc |= ctrl_cmd_install(CTRL_NODE_BTS, filter_name(ctx, &cmd_bts_##NAME)); \
+
+HO_CFG_ALL_MEMBERS
+#undef HO_CFG_ONE_MEMBER
+
+	return rc;
+}
diff --git a/src/osmo-bsc/osmo_bsc_ctrl.c b/src/osmo-bsc/osmo_bsc_ctrl.c
index 05bc86c2b..1eea6901b 100644
--- a/src/osmo-bsc/osmo_bsc_ctrl.c
+++ b/src/osmo-bsc/osmo_bsc_ctrl.c
@@ -28,6 +28,7 @@
 #include <osmocom/bsc/signal.h>
 #include <osmocom/bsc/a_reset.h>
 #include <osmocom/bsc/bts.h>
+#include <osmocom/bsc/handover_ctrl.h>
 
 #include <osmocom/core/linuxlist.h>
 #include <osmocom/core/signal.h>
@@ -697,6 +698,9 @@ int bsc_ctrl_cmds_install(struct gsm_network *net)
 	rc = bsc_base_ctrl_cmds_install();
 	if (rc)
 		goto end;
+	rc = bsc_ho_ctrl_cmds_install(net);
+	if (rc)
+		goto end;
 	rc = ctrl_cmd_install(CTRL_NODE_BTS, &cmd_bts_loc);
 	if (rc)
 		goto end;