microscript: add c functions

1 files changed, 49 insertions, 14 deletions

diff --git a/uscript/vm.c b/uscript/vm.c
index 363912a..c01bb0f 100644
--- a/uscript/vm.c
+++ b/uscript/vm.c
@@ -76,12 +76,59 @@ void close_upvals(struct us_val *to)
         vm.open_upvals = upval;
 }
 
+
+static
+void call_val(struct us_val callee, int argc) 
+{
+        switch (callee.type) {
+        case VAL_FUNC: {
+                struct us_func *func = get_func(callee);
+                if (argc != func->proto->argc) {
+                        log_fatal(
+                                1,
+                                "wrong number of arguments to '%s()' (%d/%d)",
+                                func->proto->name->chars,
+                                argc,
+                                func->proto->argc
+                        );
+                }
+                us_exec(func);
+                break;
+        }
+        case VAL_CFUNC: {
+                struct us_cfunc *cfunc = get_cfunc(callee);
+                if (argc != cfunc->argc) {
+                        log_fatal(
+                                1,
+                                "wrong number of arguments to '%s()' (%d/%d)",
+                                cfunc->name->chars,
+                                argc,
+                                cfunc->argc
+                        );
+                }
+
+                vm.cf++;
+                vm.cf->func = wrap_cfunc(cfunc);
+                vm.cf->stackbot = vm.stacktop - argc;
+                cfunc->c(argc);
+                struct us_val ret_val = vm_pop();
+                vm.stacktop = vm.cf->stackbot - 1;
+                vm.cf--;
+                vm_push(ret_val);
+                break;
+        }
+        default:
+                log_fatal(1, "cannot call that value");
+                break;
+        }
+}
+
 void us_exec(struct us_func *func)
 {
 #define read_byte() (func->proto->bytecode[++i])
 #define read_const() (func->proto->constants[read_byte()])
         vm.cf++;
-        vm.cf->func = func;
+        vm.cf->func = wrap_func(func);
         vm.cf->stackbot = vm.stacktop - func->proto->argc;
         
         for (int i = 0; i < da_len(func->proto->bytecode); i++) {
@@ -344,19 +391,7 @@ void us_exec(struct us_func *func)
                 case BC_CALL: {
                         int argc = read_byte();
                         struct us_val callee = vm.stacktop[-argc - 1];
-                        if (callee.type != VAL_FUNC)
-                                log_fatal(1, "can only call functions");
-                        struct us_func *func = get_func(callee);
-                        if (argc != func->proto->argc) {
-                                log_fatal(
-                                        1,
-                                        "wrong number of arguments to '%s()' (%d/%d)",
-                                        func->proto->name->chars,
-                                        argc,
-                                        func->proto->argc
-                                );
-                        }
-                        us_exec(func);
+                        call_val(callee, argc);
                         break;
                 }
                 case BC_RET: {