1 files changed, 92 insertions, 0 deletions
diff --git a/class.c b/class.c
index eebb46c33c..2c66c396cc 100644
--- a/class.c
+++ b/class.c
@@ -1853,6 +1853,98 @@ rb_scan_args(int argc, const VALUE *argv, const char *fmt, ...)
     return argc;
 }
 
+NORETURN(static void keyword_error(const char *error, VALUE keys));
+static void
+keyword_error(const char *error, VALUE keys)
+{
+    const char *msg = RARRAY_LEN(keys) == 1 ? "" : "s";
+    keys = rb_ary_join(keys, rb_usascii_str_new2(", "));
+    rb_raise(rb_eArgError, "%s keyword%s: %"PRIsVALUE, error, msg, keys);
+}
+
+NORETURN(static void unknown_keyword_error(VALUE hash, const ID *table, int keywords));
+static void
+unknown_keyword_error(VALUE hash, const ID *table, int keywords)
+{
+    VALUE keys;
+    int i;
+    for (i = 0; i < keywords; i++) {
+	rb_hash_delete(hash, ID2SYM(table[i]));
+    }
+    keys = rb_funcall(hash, rb_intern("keys"), 0, 0);
+    if (!RB_TYPE_P(keys, T_ARRAY)) rb_raise(rb_eArgError, "unknown keyword");
+    keyword_error("unknown", keys);
+}
+
+static int
+separate_symbol(st_data_t key, st_data_t value, st_data_t arg)
+{
+    VALUE *kwdhash = (VALUE *)arg;
+
+    if (!SYMBOL_P(key)) kwdhash++;
+    if (!*kwdhash) *kwdhash = rb_hash_new();
+    rb_hash_aset(*kwdhash, (VALUE)key, (VALUE)value);
+    return ST_CONTINUE;
+}
+
+VALUE
+rb_extract_keywords(VALUE *orighash)
+{
+    VALUE parthash[2] = {0, 0};
+    VALUE hash = *orighash;
+
+    if (RHASH_EMPTY_P(hash)) {
+	*orighash = 0;
+	return hash;
+    }
+    st_foreach(rb_hash_tbl_raw(hash), separate_symbol, (st_data_t)&parthash);
+    *orighash = parthash[1];
+    return parthash[0];
+}
+
+int
+rb_get_kwargs(VALUE keyword_hash, const ID *table, int required, int optional, VALUE *values)
+{
+    int i = 0, j;
+    VALUE missing = Qnil;
+
+    if (values) {
+	for (j = 0; j < required + optional; j++) {
+	    values[j] = Qundef;
+	}
+    }
+    if (required) {
+	for (; i < required; i++) {
+	    VALUE keyword = ID2SYM(table[i]);
+	    if (keyword_hash) {
+		st_data_t val;
+		if (st_lookup(rb_hash_tbl_raw(keyword_hash), (st_data_t)keyword, &val)) {
+		    if (values) values[i] = (VALUE)val;
+		    continue;
+		}
+	    }
+	    if (NIL_P(missing)) missing = rb_ary_tmp_new(1);
+	    rb_ary_push(missing, keyword);
+	}
+	if (!NIL_P(missing)) {
+	    keyword_error("missing", missing);
+	}
+    }
+    if (optional && keyword_hash) {
+	for (j = i, i = 0; i < optional; i++) {
+	    st_data_t val;
+	    if (st_lookup(rb_hash_tbl_raw(keyword_hash), ID2SYM(table[required+i]), &val)) {
+		if (values) values[required+i] = (VALUE)val;
+		j++;
+	    }
+	}
+	if (RHASH_SIZE(keyword_hash) > (unsigned int)j) {
+	    unknown_keyword_error(keyword_hash, table, required+optional);
+	}
+    }
+    return j;
+}
+
 /*!
  * \}
  */