Implement and test booleans

nelhage · Jan 3, 2009 · 1c6f89c · 1c6f89c
1 parent b49cf2d
commit 1c6f89c
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Showing 3 changed files with 43 additions and 0 deletions.
diff --git a/scgc.c b/scgc.c
@@ -4,6 +4,8 @@
 
 #define STRLEN2CELLS(x) (ROUNDUP(((uint32_t)(x)),sizeof(gc_handle))/sizeof(gc_handle))
 
+gc_handle sc_true, sc_false;
+
 /* Types */
 typedef struct sc_cons {
     gc_chunk header;
@@ -25,6 +27,11 @@ typedef struct sc_vector {
     gc_handle vector[];
 } sc_vector;
 
+typedef struct sc_boolean {
+    gc_chunk header;
+    int      val;
+} sc_boolean;
+
 /* Op functions */
 
 uint32_t sc_len_string(gc_chunk *v) {
@@ -39,6 +46,10 @@ uint32_t sc_len_vector(gc_chunk *v) {
     return 1 + ((sc_vector*)v)->veclen;
 }
 
+uint32_t sc_len_boolean(gc_chunk *v UNUSED) {
+    return 1;
+}
+
 void sc_relocate_cons(gc_chunk *v) {
     sc_cons *cons = (sc_cons*)v;
     gc_relocate(&cons->car);
@@ -75,6 +86,11 @@ static struct gc_ops sc_vector_ops = {
     .op_len      = sc_len_vector
 };
 
+static struct gc_ops sc_boolean_ops = {
+    .op_relocate = gc_relocate_nop,
+    .op_len      = sc_len_boolean
+};
+
 /* Public API */
 
 gc_handle sc_car(gc_handle c) {
@@ -161,6 +177,10 @@ int sc_vectorp(gc_handle c) {
     return sc_pointer_typep(c, &sc_vector_ops);
 }
 
+int sc_booleanp(gc_handle c) {
+    return sc_pointer_typep(c, &sc_boolean_ops);
+}
+
 int sc_numberp(gc_handle c) {
     return gc_numberp(c);
 }
@@ -201,3 +221,10 @@ gc_handle sc_make_string(char *string) {
     strcpy(sc_string_get(s), string);
     return s;
 }
+
+void sc_init() {
+    sc_true = gc_tag_pointer(gc_alloc(&sc_boolean_ops, 2));
+    UNTAG_PTR(sc_true, sc_boolean)->val = 1;
+    sc_false = gc_tag_pointer(gc_alloc(&sc_boolean_ops, 2));
+    UNTAG_PTR(sc_false, sc_boolean)->val = 0;
+}
diff --git a/scgc.h b/scgc.h
@@ -35,5 +35,11 @@ int sc_stringp(gc_handle c);
 int sc_numberp(gc_handle c);
 int sc_symbolp(gc_handle c);
 int sc_vectorp(gc_handle c);
+int sc_booleanp(gc_handle c);
+
+extern gc_handle sc_true;
+extern gc_handle sc_false;
+
+void sc_init();
 
 #endif
diff --git a/tests.c b/tests.c
@@ -9,6 +9,7 @@ gc_handle reg1, reg2;
 
 static void gc_core_setup(void) {
     gc_init();
+    sc_init();
     reg1 = reg2 = NIL;
     gc_register_roots(&reg1, &reg2, NULL);
 }
@@ -36,6 +37,14 @@ START_TEST(gc_sanity_check)
 }
 END_TEST
 
+START_TEST(gc_booleans)
+{
+    fail_unless(sc_booleanp(sc_true));
+    fail_unless(sc_booleanp(sc_false));
+    fail_unless(sc_true != sc_false);
+}
+END_TEST
+
 START_TEST(objs_survive_gc)
 {
     reg1 = sc_alloc_cons();
@@ -270,6 +279,7 @@ Suite *gc_suite()
                               gc_core_setup,
                               gc_core_teardown);
     tcase_add_test(tc_core, gc_sanity_check);
+    tcase_add_test(tc_core, gc_booleans);
     tcase_add_test(tc_core, objs_survive_gc);
     tcase_add_test(tc_core, gc_frees_mem);
     tcase_add_test(tc_core, gc_cons_cycle);