1 files changed, 76 insertions, 2 deletions

diff --git a/sloth.c b/sloth.c
index 5db7df0..9cb045a 100644
--- a/sloth.c
+++ b/sloth.c
@@ -2,6 +2,23 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <xxhash.h>
+
+SlothError sloth_init(Sloth *ctx)
+{
+	SlothError err;
+	err = sloth_dict_append(ctx, SLOTH_DICT_C("+", sloth_add));
+	if (err != NULL) {
+		sloth_deinit(ctx);
+		return err;
+	}
+	err = sloth_dict_append(ctx, SLOTH_DICT_C(".", sloth_write));
+	if (err != NULL) {
+		sloth_deinit(ctx);
+		return err;
+	}
+	return NULL;
+}
 
 void sloth_deinit(Sloth *ctx)
 {
@@ -9,14 +26,43 @@ void sloth_deinit(Sloth *ctx)
 		free(ctx->stack);
 		ctx->stack = NULL;
 	}
+	while (ctx->dict != NULL) {
+		SlothDict *const next = ctx->dict->next;
+		free(ctx->dict);
+		ctx->dict = next;
+	}
 }
 
-SlothError sloth_exec(Sloth *ctx, const char *s)
+SlothError sloth_dict_append(Sloth *ctx, SlothDict dict)
 {
-	printf("exec %s\n", s);
+	SlothDict **dest;
+	if (ctx->dict == NULL)
+		dest = &ctx->dict;
+	else {
+		SlothDict *last = ctx->dict;
+		while (last->next != NULL)
+			last = last->next;
+		dest = &last->next;
+	}
+	*dest = malloc(sizeof(SlothDict));
+	if (*dest == NULL)
+		return "sloth_dict_append: malloc failed";
+	memcpy(*dest, &dict, sizeof(SlothDict));
 	return NULL;
 }
 
+SlothError sloth_exec(Sloth *ctx, const char *s)
+{
+	const SlothHash hash = XXH32(s, strlen(s), 0);
+	for (SlothDict *dict = ctx->dict; dict != NULL; dict = dict->next)
+		if (dict->hash == hash) {
+			const SlothError err = dict->func(ctx);
+			if (err != NULL)
+				return err;
+		}
+	return "sloth_exec: unrecognized token";
+}
+
 SlothError sloth_exec_line(Sloth *ctx, char *s)
 {
 	static const char *sep = "\t\n\v\f\r ";
@@ -56,6 +102,34 @@ SlothError sloth_push(Sloth *ctx, SlothByte v)
 	return NULL;
 }
 
+SlothError sloth_add(Sloth *ctx)
+{
+	SlothError err;
+	SlothByte a, b;
+	err = sloth_pop(ctx, &a);
+	if (err != NULL)
+		return err;
+	err = sloth_pop(ctx, &b);
+	if (err != NULL)
+		return err;
+	a += b;
+	err = sloth_push(ctx, a);
+	if (err != NULL)
+		return err;
+	return NULL;
+}
+
+SlothError sloth_write(Sloth *ctx)
+{
+	SlothError err;
+	SlothByte a;
+	err = sloth_pop(ctx, &a);
+	if (err != NULL)
+		return err;
+	printf("%c", (unsigned char)a);
+	return NULL;
+}
+
 void sloth_inspect_stack(const Sloth *ctx)
 {
 	printf("<%lu> ", ctx->stack_size);