First commit

1 files changed, 43 insertions, 0 deletions

diff --git a/src/op/check/block.c b/src/op/check/block.c
new file mode 100644
index 0000000..7d5176e
--- /dev/null
+++ b/src/op/check/block.c
@@ -0,0 +1,43 @@
+/*
+ * nanowasm, a tiny WebAssembly/Wasm interpreter
+ * Copyright (C) 2023-2025  Xavier Del Campo Romero
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <nanowasm/nw.h>
+#include <nw/io.h>
+#include <nw/log.h>
+#include <nw/ops.h>
+#include <nw/types.h>
+
+static enum nw_state get_type(struct nw_mod *const m)
+{
+    nw_varint7 type;
+    const struct nw_io_cfg *const cfg = &m->cfg.io;
+    struct nw_sm_c *const c = &m->sm.code;
+    struct nw_sm_leb128 *const l = &c->leb128;
+    const enum nw_state n = nwp_varint7(cfg, l, &type, cfg->user);
+    enum nw_type t;
+
+    if (n)
+        return n;
+    else if (nwp_get_type(type, &t) && type != 0x40)
+    {
+#ifdef NW_LOG
+        nwp_log("invalid block_type %#x\n", (unsigned)type);
+#endif
+        return NW_FATAL;
+    }
+
+    c->fn.blocks++;
+    m->next = m->sm.code.next;
+    return NW_AGAIN;
+}
+
+void nwp_op_check_block(struct nw_mod *const m)
+{
+    m->next = get_type;
+}