Implemented setcontrol and packet

groundStation/src/backend/bitwise.h

@@ -2,28 +2,28 @@
 #define _bitwise_h
 
 /* Bit shifting for endianness of 16-bit numbers */
-#define LSByte16(x) (x & 0xff)
-#define MSByte16(x) ((x >> 8) & 0xff)
+#define LSByte16(x) ((x) & 0xff)
+#define MSByte16(x) (((x) >> 8) & 0xff)
 
 /* Build a 16-bit integer out of two bytes */
-#define BytesTo16(lsb, msb) ((lsb & 0xff) | ((msb << 8) & 0xff))
+#define BytesTo16(lsb, msb) (((lsb) & 0xff) | (((msb) << 8) & 0xff))
 
 /* Break apart a float. Sadly this is UB, but the "correct" way
  * to do this involves actually implementing
  * IEEE 754 in software to do so
  */
-#define FloatByte1(x) (((char *) x)[0])
-#define FloatByte2(x) (((char *) x)[1])
-#define FloatByte3(x) (((char *) x)[2])
-#define FloatByte4(x) (((char *) x)[3])
+#define FloatByte1(x) (((char *) &(x))[0])
+#define FloatByte2(x) (((char *) &(x))[1])
+#define FloatByte3(x) (((char *) &(x))[2])
+#define FloatByte4(x) (((char *) &(x))[3])
 
 /* This is so much UB it hurts to write */
 #define BytesToFloat(f, b1, b2, b3, b4) \
 	do {                                \
-		((char *) f)[0] = b1;           \
-		((char *) f)[1] = b2;           \
-		((char *) f)[2] = b3;           \
-		((char *) f)[3] = b4;           \
+		((char *) &(f))[0] = (b1);      \
+		((char *) &(f))[1] = (b2);      \
+		((char *) &(f))[2] = (b3);      \
+		((char *) &(f))[3] = (b4);      \
 	} while (0);
 
 #endif

groundStation/src/backend/common/common.txt

+The common files are:
+ - packet.h
+ - packet.c
+ - setcontrol.h
+ - setcontrol.c
+ - bitwise.h
+ - controller.h

groundStation/src/backend/controller.h

 #ifndef _controller_h
 #define _controller_h
 
+
+/* For now, the enums come from commands.h */
+#include "commands.h"
+#if 0
 enum ControllerID {
 	ROLL_ID,              // 00 - Roll PID
 	PITCH_ID,             // 01 - Pitch PID
@@ -19,6 +23,7 @@ enum ControllerValueID{
     KD_ID,                 // 02 - D constant
     SP_ID,                 // 03 - Setpoint value
 };
+#endif
 
 struct controller_message {
 	enum ControllerID id;

groundStation/src/backend/packet.c

@@ -84,7 +84,12 @@ ssize_t DecodePacket(
 	memcpy(data, &packet[HDR_SIZE], m->data_len);
 
 	/* Validate checksum */
-	// TODO
-	//
+	/* TODO */
 	return m->data_len;
 }
+
+uint8_t PacketChecksum(const uint8_t * packet, size_t packet_size)
+{
+	/* TODO implement */
+	return 42;
+}

groundStation/src/backend/setcontrol.c

 #include "setcontrol.h"
-#include "../commands.h"
+#include "commands.h"
+#include "bitwise.h"
 
 #include <sys/types.h>