add a hook func that is called on every code invocation

Makefile

@@ -29,7 +29,7 @@ $(LIBCS_LIB): $(LIBCS_OBJ)
 
 repl: $(LIBCS_LIB) tools/repl.cc tools/linenoise.cc tools/linenoise.hh
 	$(CXX) $(CXXFLAGS) $(LIBCS_CXXFLAGS) $(LDFLAGS) \
-	-Itools -DCS_REPL_USE_LINENOISE -DCS_REPL_HAS_COMPLETE -DCS_REPL_HAS_HINTS \
+	-Itools -DCS_REPL_USE_READLINE -L/usr/local/lib -lreadline -I/usr/local/include -DCS_REPL_HAS_HINTS -DCS_REPL_HAS_COMPLETE \
 	tools/linenoise.cc tools/repl.cc -o repl $(LIBCS_LIB)
 
 clean:

cs_vm.cc

@@ -581,6 +581,10 @@ static ostd::Uint32 *runcode(CsState &cs, ostd::Uint32 *code, CsValue &result) {
     ++rundepth;
     int numargs = 0;
     CsValue args[MaxArguments + MaxResults];
+    auto &chook = cs.get_call_hook();
+    if (chook) {
+        chook();
+    }
     for (;;) {
         ostd::Uint32 op = *code++;
         switch (op & 0xFF) {

cubescript.cc

@@ -381,6 +381,20 @@ void CsState::set_err(CsStream &s) {
     p_err = &s;
 }
 
+CsHookCb CsState::set_call_hook(CsHookCb func) {
+    auto hk = ostd::move(p_callhook);
+    p_callhook = ostd::move(func);
+    return hk;
+}
+
+CsHookCb const &CsState::get_call_hook() const {
+    return p_callhook;
+}
+
+CsHookCb &CsState::get_call_hook() {
+    return p_callhook;
+}
+
 void CsState::clear_override(CsIdent &id) {
     if (!(id.get_flags() & IDF_OVERRIDDEN)) {
         return;

cubescript.hh

@@ -315,6 +315,8 @@ enum {
     CS_LIB_ALL    = 0b111
 };
 
+using CsHookCb = ostd::Function<void()>;
+
 struct OSTD_EXPORT CsState {
     CsMap<ostd::ConstCharRange, CsIdent *> idents;
     CsVector<CsIdent *> identmap;
@@ -336,6 +338,10 @@ struct OSTD_EXPORT CsState {
     CsStream &get_err();
     void set_err(CsStream &s);
 
+    CsHookCb set_call_hook(CsHookCb func);
+    CsHookCb const &get_call_hook() const;
+    CsHookCb &get_call_hook();
+
     void init_libs(int libs = CS_LIB_ALL);
 
     void clear_override(CsIdent &id);
@@ -454,6 +460,7 @@ struct OSTD_EXPORT CsState {
 private:
     CsIdent *add_ident(CsIdent *id);
 
+    CsHookCb p_callhook;
     CsStream *p_out, *p_err;
 };