First commit

1 files changed, 148 insertions, 0 deletions

diff --git a/src/routines/section/global.c b/src/routines/section/global.c
new file mode 100644
index 0000000..6223fc9
--- /dev/null
+++ b/src/routines/section/global.c
@@ -0,0 +1,148 @@
+/*
+ * 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/interp.h>
+#include <nw/io.h>
+#include <nw/log.h>
+#include <nw/routines.h>
+#include <nw/types.h>
+#include <limits.h>
+#include <string.h>
+
+static enum nw_state get_content_type(struct nw_mod *);
+
+static int push(const void *const src, const size_t n, void *const user)
+{
+    struct nw_mod *const m = user;
+    struct nw_sm_gl *const gl = &m->sm.global;
+
+    if (n > sizeof gl->value)
+    {
+#ifdef NW_LOG
+        nwp_log("stack overflow\n");
+#endif
+        return -1;
+    }
+
+    memcpy(&gl->value, src, n);
+    return n;
+}
+
+static enum nw_state loop(struct nw_mod *const m)
+{
+    struct nw_sm_gl *const gl = &m->sm.global;
+    const enum nw_state n = nwp_interp_run(&gl->interp);
+
+    if (n)
+        return n;
+
+    m->next = ++gl->entry_i >= m->global_count ?
+        nwp_section_exit : get_content_type;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_global(struct nw_mod *const m)
+{
+    struct nw_sm_gl *const gl = &m->sm.global;
+    struct nw_interp_cfg cfg = {0};
+
+    cfg.m = m;
+    cfg.io = m->cfg.io;
+    cfg.user = m;
+    cfg.stack.push = push;
+
+    if (nwp_interp_start(&gl->interp, &cfg, &nwp_interp_initexpr_set))
+    {
+#ifdef NW_LOG
+        nwp_log("nw_interp_start failed\n");
+#endif
+        return NW_FATAL;
+    }
+
+    m->next = loop;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_mutability(struct nw_mod *const m)
+{
+    nw_varuint1 mutability;
+    const struct nw_io_cfg *const cfg = &m->cfg.io;
+    struct nw_sm_gl *const gl = &m->sm.global;
+    struct nw_sm_leb128 *const l = &gl->leb128;
+    const enum nw_state n = nwp_varuint1(cfg, l, &mutability, cfg->user);
+
+    if (n)
+        return n;
+
+    m->next = get_global;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_content_type(struct nw_mod *const m)
+{
+    nw_varint7 content_type;
+    const struct nw_io_cfg *const cfg = &m->cfg.io;
+    struct nw_sm_gl *const gl = &m->sm.global;
+    struct nw_sm_leb128 *const l = &gl->leb128;
+    const enum nw_state n = nwp_varint7(cfg, l, &content_type, cfg->user);
+    enum nw_type type;
+
+    /* TODO: do not ignore type */
+    if (n)
+        return n;
+    else if (nwp_get_type(content_type, &type))
+    {
+#ifdef NW_LOG
+        nwp_log("nwp_get_type failed\n");
+#endif
+        return NW_FATAL;
+    }
+
+    m->next = get_mutability;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_count(struct nw_mod *const m)
+{
+    const struct nw_io_cfg *const cfg = &m->cfg.io;
+    struct nw_sm_gl *const gl = &m->sm.global;
+    struct nw_sm_leb128 *const l = &gl->leb128;
+    enum nw_state n;
+
+    if (!m->sections[NW_SECTION_IMPORT])
+    {
+#ifdef NW_LOG
+        nwp_log("global section found before import section\n");
+#endif
+        return NW_FATAL;
+    }
+    else if ((n = nwp_varuint32(cfg, l, &m->global_count, cfg->user)))
+        return n;
+    else if (m->global_count > ULONG_MAX / sizeof (struct nw_global))
+    {
+#ifdef NW_LOG
+        nwp_log("global_count too large: %lu\n",
+            (unsigned long)m->global_count);
+#endif
+        return NW_FATAL;
+    }
+
+    m->out.global = m->global_count * sizeof (struct nw_global);
+    m->next = m->global_count ? get_content_type : nwp_section_exit;
+    return NW_AGAIN;
+}
+
+void nwp_section_global(struct nw_mod *const m)
+{
+    const struct nw_sm_gl g = {0};
+
+    m->sm.global = g;
+    m->next = get_count;
+}