Initial public release of SystemK.

Protocols/Test.c

@@ -0,0 +1,144 @@
+
+/*
+ * This program source code file is part of SystemK, a library in the KTag project.
+ *
+ * 🛡️ <https://ktag.clubk.club> 🃞
+ *
+ * Copyright © 2016-2025 Joseph P. Kearney and the KTag developers.
+ *
+ * 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.
+ *
+ * There should be a copy of the GNU Affero General Public License in the LICENSE
+ * file in the root of this repository.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+
+#include "SystemK.h"
+
+static const char *KLOG_TAG = "Test Protocol";
+
+#define TEST_PULSE_SUBTRAHEND_IN_us 300
+//! The shortest test packet is a two marks, the first of duration (3 * TEST_PULSE_SUBTRAHEND_IN_us), and the second of duration TEST_PULSE_SUBTRAHEND_IN_us.
+#define TEST_MINIMUM_LONGEST_PULSE_DURATION_IN_us (3 * TEST_PULSE_SUBTRAHEND_IN_us)
+#define TEST_TOLERANCE_IN_us ((TEST_PULSE_SUBTRAHEND_IN_us / 2) - 1)
+
+static TimedPulseTrain_T Tag_Send_Buffer;
+static DecodedPacket_T Test_Tag_Received_Buffers[3] =
+    {
+        {.Tag.type = DECODED_PACKET_TYPE_BUFFER_FREE},
+        {.Tag.type = DECODED_PACKET_TYPE_BUFFER_FREE},
+        {.Tag.type = DECODED_PACKET_TYPE_BUFFER_FREE}};
+
+static inline DecodedPacket_T *Get_Tag_Packet_Buffer(void)
+{
+    if (Test_Tag_Received_Buffers[0].Tag.type == DECODED_PACKET_TYPE_BUFFER_FREE)
+    {
+        return &Test_Tag_Received_Buffers[0];
+    }
+    else if (Test_Tag_Received_Buffers[1].Tag.type == DECODED_PACKET_TYPE_BUFFER_FREE)
+    {
+        return &Test_Tag_Received_Buffers[1];
+    }
+    else
+    {
+        // Just use it.
+        return &Test_Tag_Received_Buffers[2];
+    }
+}
+
+static inline void PackPulseTrain(TimedPulseTrain_T *pulsetrain, uint32_t longest_pulse_duration_in_us)
+{
+    uint_fast8_t index = 0;
+    uint32_t next_pulse_duration_in_us = longest_pulse_duration_in_us;
+    TimedBit_T next_bit;
+
+    if (next_pulse_duration_in_us < TEST_MINIMUM_LONGEST_PULSE_DURATION_IN_us)
+    {
+        next_pulse_duration_in_us = TEST_MINIMUM_LONGEST_PULSE_DURATION_IN_us;
+    }
+
+    while ((next_pulse_duration_in_us >= TEST_PULSE_SUBTRAHEND_IN_us) && (index < MAX_PULSES))
+    {
+        // Even indicies are marks.
+        if ((index % 2) == 0)
+        {
+            next_bit.symbol = MARK;
+        }
+        // Odd indicies are spaces.
+        else
+        {
+            next_bit.symbol = SPACE;
+        }
+        next_bit.duration = next_pulse_duration_in_us;
+        pulsetrain->bitstream[index] = next_bit;
+
+        next_pulse_duration_in_us = next_pulse_duration_in_us - TEST_PULSE_SUBTRAHEND_IN_us;
+        index++;
+    }
+
+    // Mark the end of the train.
+    next_bit.symbol = SPACE;
+    next_bit.duration = LAST_PULSE;
+    pulsetrain->bitstream[index] = next_bit;
+    pulsetrain->count = index;
+}
+
+TimedPulseTrain_T *TEST_EncodePacket(TagPacket_T *packet)
+{
+    uint32_t packed_data = 2100;
+
+    PackPulseTrain(&Tag_Send_Buffer, packed_data);
+
+    return &Tag_Send_Buffer;
+}
+
+DecodedPacket_T *TEST_MaybeDecodePacket(TimedPulseTrain_T *packet)
+{
+    // packet->bitstream[0] is the longest pulse--assume it was received correctly.
+    uint32_t longest_pulse_duration_in_us = packet->bitstream[0].duration;
+
+    if ((longest_pulse_duration_in_us - TEST_TOLERANCE_IN_us) < TEST_MINIMUM_LONGEST_PULSE_DURATION_IN_us)
+    {
+        // The first pulse is too short!
+        return NULL;
+    }
+
+    for (uint_fast8_t index = 1; index < packet->count; index++)
+    {
+        uint32_t expected_pulse_duration_in_us = longest_pulse_duration_in_us - (index * TEST_PULSE_SUBTRAHEND_IN_us);
+
+        if (packet->bitstream[index].duration < (expected_pulse_duration_in_us - TEST_TOLERANCE_IN_us))
+        {
+            KLOG_WARN(KLOG_TAG, "Pulse %u is too short! Expected %lu; received %u.", index, expected_pulse_duration_in_us, packet->bitstream[index].duration);
+            return NULL;
+        }
+        if (packet->bitstream[index].duration > (expected_pulse_duration_in_us + TEST_TOLERANCE_IN_us))
+        {
+            KLOG_WARN(KLOG_TAG, "Pulse %u is too long! Expected %lu; received %u.", index, expected_pulse_duration_in_us, packet->bitstream[index].duration);
+            return NULL;
+        }
+    }
+
+    DecodedPacket_T *Command_Rx_Buffer = Get_Tag_Packet_Buffer();
+    Command_Rx_Buffer->Command.type = DECODED_PACKET_TYPE_COMMAND_RECEIVED;
+    Command_Rx_Buffer->Command.protocol = TEST_PROTOCOL;
+    Command_Rx_Buffer->Command.data = longest_pulse_duration_in_us;
+    return Command_Rx_Buffer;
+}
+
+color_t TEST_GetTeamColor(__attribute__((unused)) uint8_t team_ID)
+{
+    color_t result = COLOR_WHITE;
+
+    return result;
+}