FHSS: Added copyright headers, comments etc.

Author: Jarkko Paso

source/Service_Libs/fhss/channel_functions.c

@@ -1,5 +1,44 @@
+/*
+ * Copyright (c) 2016-2017, Arm Limited and affiliates.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 #include "nsconfig.h"
 
+#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
+
+#define final(a,b,c) \
+{ \
+    c ^= b; c -= rot(b, 14); \
+    a ^= c; a -= rot(c, 11); \
+    b ^= a; b -= rot(a, 25); \
+    c ^= b; c -= rot(b, 16); \
+    a ^= c; a -= rot(c, 4); \
+    b ^= a; b -= rot(a, 14); \
+    c ^= b; c -= rot(b, 24); \
+}
+
+#define mix(a,b,c) \
+{ \
+    a -= c; a ^= rot(c, 4); c += b; \
+    b -= a; b ^= rot(a, 6); a += c; \
+    c -= b; c ^= rot(b, 8); b += a; \
+    a -= c; a ^= rot(c, 16); c += b; \
+    b -= a; b ^= rot(a, 19); a += c; \
+    c -= b; c ^= rot(b, 4); b += a; \
+}
+
 static uint32_t global_seed = 1;
 
 void tr51_seed_rand(uint32_t seed)
@@ -45,7 +84,7 @@ void tr51_compute_cfd(uint8_t *mac, uint8_t *first_element, uint8_t *step_size,
     *step_size = (mac[7] % (channel_table_length - 1)) + 1;
 }
 
-uint8_t tr51_find_excluded(int32_t channel, uint16_t *excluded_channels, uint16_t number_of_excluded_channels)
+static uint8_t tr51_find_excluded(int32_t channel, uint16_t *excluded_channels, uint16_t number_of_excluded_channels)
 {
     uint8_t count = 0;
     if (excluded_channels != NULL) {
@@ -78,29 +117,6 @@ uint16_t tr51_calculate_hopping_sequence(int32_t *channel_table, uint16_t channe
     return slot;
 }
 
-#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
-
-#define final(a,b,c) \
-{ \
-    c ^= b; c -= rot(b, 14); \
-    a ^= c; a -= rot(c, 11); \
-    b ^= a; b -= rot(a, 25); \
-    c ^= b; c -= rot(b, 16); \
-    a ^= c; a -= rot(c, 4); \
-    b ^= a; b -= rot(a, 14); \
-    c ^= b; c -= rot(b, 24); \
-}
-
-#define mix(a,b,c) \
-{ \
-    a -= c; a ^= rot(c, 4); c += b; \
-    b -= a; b ^= rot(a, 6); a += c; \
-    c -= b; c ^= rot(b, 8); b += a; \
-    a -= c; a ^= rot(c, 16); c += b; \
-    b -= a; b ^= rot(a, 19); a += c; \
-    c -= b; c ^= rot(b, 4); b += a; \
-}
-
 static uint32_t dh1cf_hashword(const uint32_t *key, size_t key_length, uint32_t init_value)
 {
     uint32_t a,b,c;

source/Service_Libs/fhss/channel_functions.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016-2017, Arm Limited and affiliates.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @brief Calculate channel table based on TR51 channel function.
+ * @param number_of_channels Number of channels in table.
+ * @param nearest_prime Nearest prime number. Must be equal to or larger than number_of_channels.
+ * @param channel_table Output channel table. Has to be at least nearest_prime in length.
+ */
+void tr51_calculate_channel_table(uint16_t number_of_channels, uint16_t nearest_prime, int32_t *channel_table);
+
+/**
+ * @brief Calculate hopping sequence for a specific peer.
+ * @param channel_table Used channel table.
+ * @param channel_table_length Length of the used channel table.
+ * @param first_element Start generated by CFD function.
+ * @param step_size Step size generated by CFD function.
+ * @param output_table Output hopping sequence table.
+ * @param excluded_channels List of not used channels.
+ * @param number_of_excluded_channels Number of not used channels.
+ * @return Number of channels in sequence.
+ */
+uint16_t tr51_calculate_hopping_sequence(int32_t *channel_table, uint16_t channel_table_length, uint8_t first_element, uint8_t step_size, int32_t *output_table, uint16_t *excluded_channels, uint16_t number_of_excluded_channels);
+
+/**
+ * @brief Compute the unicast schedule channel index.
+ * @param slot_number Current slot number.
+ * @param mac MAC address of the node for which the index is calculated.
+ * @param number_of_channels Number of channels.
+ * @return Channel index.
+ */
+int32_t dh1cf_get_uc_channel_index(uint16_t slot_number, uint8_t *mac, int16_t number_of_channels);
+
+/**
+ * @brief Compute the broadcast schedule channel index.
+ * @param slot_number Current slot number.
+ * @param bsi Broadcast schedule identifier of the node for which the index is calculated.
+ * @param number_of_channels Number of channels.
+ * @return Channel index.
+ */
+int32_t dh1cf_get_bc_channel_index(uint16_t slot_number, uint16_t bsi, int16_t number_of_channels);