Rearrange some of the files, to reduce the footprint of included headers

include/atomlayer.h → include/baggage.h

-#ifndef _ATOM_LAYER_H_
-#define _ATOM_LAYER_H_
+#ifndef _BAGGAGE_H_
+#define _BAGGAGE_H_
 
 #include <iostream>
 #include <cstdint>
@@ -7,39 +7,46 @@
 #include <vector>
 
 
+/*
+This file defines the main interfaces (Atoms and Baggage) of the Brown Tracing Plane
+
+Most interactions will be with Baggage and ThreadLocalBaggage
+*/
+
+
+// An atom is just an array of bytes
 struct Atom {
 
 	std::vector<uint8_t> bytes;
 
 	Atom() : bytes(0) {}
-
-	Atom(int x) : bytes(4) {
-		for (unsigned i = 0; i < 4; i++) {
-			bytes[3-i] = (x >> (i * 8));
-		}
-	}
-
+	Atom(int size) : bytes(size) {}
 	Atom(std::vector<uint8_t> bytes) : bytes(bytes) {}
 
+	// Lexicographic comparison of two atoms
 	const int compare(const Atom& other);
 
 	friend std::ostream& operator<< ( std::ostream& os, const Atom& atom );
-
 };
 
 
+// Baggage is an array of atoms
 struct Baggage {
 
 	std::vector<Atom> atoms;
 
 	Baggage() : atoms(0) {}
 
+	// Duplicates this baggage
 	Baggage branch();
 
+	// Lexicographic merge of two baggage instances, as defined in the Brown Tracing Plane
 	static Baggage merge(Baggage& a, Baggage& b);
 
+	// Serialize this baggage, as defined in the Brown Tracing Plane (length-prefix each atom in order)
 	std::vector<uint8_t> serialize();
 
+	// Deserialize a serialized baggage instance, as defined in the Brown Tracing Plane
 	static Baggage deserialize(std::vector<uint8_t> bytes);
 
 	friend std::ostream& operator<< ( std::ostream& os, const Baggage& baggage );
@@ -47,4 +54,18 @@ struct Baggage {
 };
 
 
+// Helper methods for storing a baggage instance in thread-local storage.  Usage is optional, but very useful
+namespace ThreadLocalBaggage {
+
+	Baggage& Get();	                     // Get the current thread's baggage
+	Baggage Take();                      // Get the current thread's baggage, and clear the thread-local storage
+	Baggage Branch();                    // Get a copy of the current thread's baggage
+
+	void Delete();                       // Delete the current thread's baggage
+	void Set(Baggage new_baggage);       // Set the current thread's baggage to the provided baggage, destroying the previous baggage
+	void Join(Baggage &otherBaggage);    // Merge the current thread's baggage with the provided baggage
+
+}
+
+
 #endif
\ No newline at end of file

include/thread_local_baggage.h

-#ifndef _THREAD_LOCAL_BAGGAGE_H_
-#define _THREAD_LOCAL_BAGGAGE_H_
-
-#include "atomlayer.h"
-
-namespace ThreadLocalBaggage {
-
-	Baggage& Get();	 // Get the current thread's baggage
-	Baggage Take();  // Get the current thread's baggage, and clear the thread-local storage
-	Baggage Branch(); // Get a copy of the current thread's baggage
-
-	void Delete();  // Delete the current thread's baggage
-	void Set(Baggage new_baggage);
-	void Join(Baggage &otherBaggage);
-
-}
-
-
-#endif
\ No newline at end of file

src/atomlayer.cpp

-#include "atomlayer.h"
+#include "baggage.h"
 
 #include <iostream>
 #include <cstdint>

include/baggageprotocol.h → src/baggageprotocol.h

 #ifndef _BAGGAGE_PROTOCOL_H_
 #define _BAGGAGE_PROTOCOL_H_
 
-#include "atomlayer.h"
+#include "baggage.h"
 #include "lexvarint.h"
 
 #define ATOM_TYPE_MASK 0x80

src/main.cc

 #include <iostream>
 #include <vector>
-#include "atomlayer.h"
-#include "pubsub.h"
 #include <sstream>
+#include "baggage.h"
+#include "pubsub.h"
+#include "xtrace.h"
 #include "xtrace_baggage.h"
 #include "lexvarint.h"
 #include "baggageprotocol.h"
-#include "thread_local_baggage.h"
-#include "xtrace.h"
 
 void test_vector(std::vector<int> testv) {
 	testv[0] = 5;

src/thread_local_baggage.cpp

-#include "thread_local_baggage.h"
-#include "xtrace.h"
+#include "baggage.h"
 
 
 thread_local Baggage current_threads_baggage;

src/xtrace.cpp

@@ -7,7 +7,8 @@
 #include <chrono>
 #include <time.h>
 
-#include "thread_local_baggage.h"
+
+#include "baggage.h"
 #include "xtrace.h"
 #include "xtrace.pb.h"
 #include "xtrace_baggage.h"

include/xtrace_baggage.h → src/xtrace_baggage.h

@@ -2,7 +2,7 @@
 #define _XTRACE_BAGGAGE_H_
 
 
-#include "thread_local_baggage.h"
+#include "baggage.h"
 
 namespace XTraceBaggage {