Move binpac code into the main Zeek repository

This is based on commit 48f75b5f6415fe9d597e3e991cec635b1bc400dc from
the binpac repository.

tools/binpac/src/pac_cclass.h

@@ -0,0 +1,77 @@
+#ifndef pac_cclass_h
+#define pac_cclass_h
+
+class CClass;
+class CClassMember;
+class CClassMethod;
+class CType;
+class CVariable;
+
+typedef vector<CClassMember*> CClassMemberList;
+typedef vector<CClassMethod*> CClassMethodList;
+typedef vector<CVariable*> CVariableList;
+
+#include "pac_common.h"
+
+// Represents a C++ class.
+//
+// For now we adopt a simple model:
+//
+// 1. All members have a protected member variable "name_" and a
+// public constant access method "name()".
+//
+// 2. All methods are public.
+//
+// 3. We do not check repeated names.
+
+class CClass {
+public:
+    CClass(const string& class_name);
+
+    void AddMember(CClassMember* member);
+    void AddMethod(CClassMember* method);
+
+    void GenForwardDeclaration(Output* out_h);
+    void GenCode(Output* out_h, Output* out_cc);
+
+protected:
+    string class_name_;
+    CClassMemberList* members_;
+    CClassMethodList* methods_;
+};
+
+class CVariable {
+public:
+    CClassMember(const string& name, CType* type);
+
+    string name() const { return name_; }
+    CType* type() const { return type_; }
+
+protected:
+    string name_;
+    CType* type_;
+};
+
+class CClassMember {
+public:
+    CClassMember(CVariable* var);
+    void GenCode(Output* out_h, Output* out_cc);
+
+    string decl() const;
+
+protected:
+    CVariable* var_;
+};
+
+class CClassMethod {
+public:
+    CClassMethod(CVariable* var, CVariableList* params);
+
+    string decl() const;
+
+protected:
+    CVariable* var_;
+    CVariableList* params_;
+};
+
+#endif // pac_cclass_h