WIP bytecode and routine, read more

The tests are failing in a strange way, with the error message 'corrupted top size'. I don't know what it means, and it seems to be caused by a call to printf() within 'test_bytecode.c'. I need a break, as this is making me dizzy.

source/toy_bytecode.c

@@ -0,0 +1,67 @@
+#include "toy_bytecode.h"
+
+#include "toy_memory.h"
+
+#include <stdio.h>
+#include <string.h>
+
+//utils
+static void expand(Toy_Bytecode* bc, int amount) {
+	if (bc->count + amount > bc->capacity) {
+		int oldCapacity = bc->capacity;
+
+		bc->capacity = TOY_GROW_CAPACITY(oldCapacity);
+		bc->ptr = TOY_GROW_ARRAY(unsigned char, bc->ptr, oldCapacity, bc->capacity);
+	}
+}
+
+static void emitByte(Toy_Bytecode* bc, unsigned char byte) {
+	expand(bc, 1);
+	bc->ptr[bc->count++] = byte;
+}
+
+static void writeModule(Toy_Bytecode* bc, Toy_Ast* ast) {
+	//
+}
+
+//bytecode
+static void writeBytecodeHeader(Toy_Bytecode* bc) {
+	emitByte(bc, TOY_VERSION_MAJOR);
+	emitByte(bc, TOY_VERSION_MINOR);
+	emitByte(bc, TOY_VERSION_PATCH);
+
+	//check strlen for the build string
+	const char* build = Toy_private_version_build();
+	int len = (int)strlen(build) + 1;
+
+	expand(bc, len);
+	sprintf((char*)(bc->ptr + bc->count), "%.*s", len, build);
+	bc->count += len;
+}
+
+static void writeBytecodeBody(Toy_Bytecode* bc, Toy_Ast* ast) {
+	//a 'module' is a routine that runs at the root-level of a file
+	//since routines can be recursive, this distinction is important
+	//eventually, the bytecode may support multiple modules packed into one file
+	writeModule(bc, ast);
+}
+
+//exposed functions
+Toy_Bytecode Toy_compileBytecode(Toy_Ast* ast) {
+	//setup
+	Toy_Bytecode bc;
+
+	bc.ptr = NULL;
+	bc.capacity = 0;
+	bc.count = 0;
+
+	//build
+	writeBytecodeHeader(&bc);
+	writeBytecodeBody(&bc, ast);
+
+	return bc;
+}
+
+void Toy_freeBytecode(Toy_Bytecode bc) {
+	TOY_FREE_ARRAY(unsigned char, bc.ptr, bc.capacity);
+}