introduce RxLev statistics module, an efficient way for power scan data

4 files changed, 118 insertions, 2 deletions

diff --git a/include/osmocore/Makefile.am b/include/osmocore/Makefile.am
index b45d0233..9c4fc757 100644
--- a/include/osmocore/Makefile.am
+++ b/include/osmocore/Makefile.am
@@ -1,6 +1,6 @@
 osmocore_HEADERS = signal.h linuxlist.h timer.h talloc.h msgb.h select.h \
 		   tlv.h bitvec.h comp128.h statistics.h gsm_utils.h utils.h \
-		   gsmtap.h write_queue.h rsl.h gsm48.h
+		   gsmtap.h write_queue.h rsl.h gsm48.h rxlev_stat.h
 
 osmocoredir = $(includedir)/osmocore
 
diff --git a/include/osmocore/rxlev_stat.h b/include/osmocore/rxlev_stat.h
new file mode 100644
index 00000000..415509dc
--- /dev/null
+++ b/include/osmocore/rxlev_stat.h
@@ -0,0 +1,22 @@
+#ifndef _OSMOCORE_RXLEV_STATS_H
+#define _OSMOCORE_RXLEV_STATS_H
+
+#define NUM_RXLEVS 32
+#define NUM_ARFCNS 1024
+
+struct rxlev_stats {
+	/* the maximum number of ARFCN's is 1024, and there are 32 RxLevels,
+	 * so in we keep one 1024bit-bitvec for each RxLev */
+	uint8_t rxlev_buckets[NUM_RXLEVS][NUM_ARFCNS/8];
+};
+
+void rxlev_stat_input(struct rxlev_stats *st, uint16_t arfcn, uint8_t rxlev);
+
+/* get the next ARFCN that has the specified Rxlev */
+int16_t rxlev_stat_get_next(const struct rxlev_stats *st, uint8_t rxlev, int16_t arfcn);
+
+void rxlev_stat_reset(struct rxlev_stats *st);
+
+void rxlev_stat_dump(const struct rxlev_stats *st);
+
+#endif /* _OSMOCORE_RXLEV_STATS_H */
diff --git a/src/Makefile.am b/src/Makefile.am
index b6826ea5..99424522 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -9,4 +9,4 @@ lib_LTLIBRARIES = libosmocore.la
 
 libosmocore_la_SOURCES = msgb.c timer.c talloc.c select.c signal.c \
 			 tlv_parser.c bitvec.c comp128.c gsm_utils.c statistics.c \
-			 write_queue.c utils.c rsl.c gsm48.c
+			 write_queue.c utils.c rsl.c gsm48.c rxlev_stat.c
diff --git a/src/rxlev_stat.c b/src/rxlev_stat.c
new file mode 100644
index 00000000..1bfd6795
--- /dev/null
+++ b/src/rxlev_stat.c
@@ -0,0 +1,94 @@
+/* Rx Level statistics */
+
+/* (C) 2010 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <stdint.h>
+
+#include <osmocore/bitvec.h>
+#include <osmocore/rxlev_stat.h>
+
+int bitvec_find_bit_pos(const struct bitvec *bv, unsigned int n, enum bit_value val)
+{
+	unsigned int i;
+
+	for (i = n; i < bv->data_len*8; i++) {
+		if (bitvec_get_bit_pos(bv, i) == val)
+			return i;
+	}
+
+	return -1;
+}
+
+void rxlev_stat_input(struct rxlev_stats *st, uint16_t arfcn, uint8_t rxlev)
+{
+	struct bitvec bv;
+
+	if (rxlev >= NUM_RXLEVS)
+		rxlev = NUM_RXLEVS-1;
+
+	bv.data_len = NUM_ARFCNS/8;
+	bv.data = st->rxlev_buckets[rxlev];
+
+	bitvec_set_bit_pos(&bv, arfcn, ONE);
+}
+
+/* get the next ARFCN that has the specified Rxlev */
+int16_t rxlev_stat_get_next(const struct rxlev_stats *st, uint8_t rxlev, int16_t arfcn)
+{
+	struct bitvec bv;
+
+	if (rxlev >= NUM_RXLEVS)
+		rxlev = NUM_RXLEVS-1;
+
+	bv.data_len = NUM_ARFCNS/8;
+
+	if (arfcn < 0)
+		arfcn = -1;
+
+	bv.data = st->rxlev_buckets[rxlev];
+
+	return bitvec_find_bit_pos(&bv, arfcn+1, ONE);
+}
+
+void rxlev_stat_reset(struct rxlev_stats *st)
+{
+	memset(st, 0, sizeof(*st));
+}
+
+void rxlev_stat_dump(const struct rxlev_stats *st)
+{
+	int i;
+
+	for (i = NUM_RXLEVS-1; i >= 0; i--) {
+		int16_t arfcn = -1;
+
+		printf("ARFCN with RxLev %u: ", i);
+		while ((arfcn = rxlev_stat_get_next(st, i, arfcn)) >= 0) {
+			printf("%u ", arfcn);
+		}
+		printf("\n");
+	}
+}