1 files changed, 144 insertions, 0 deletions
diff --git a/src/routines/section/global.c b/src/routines/section/global.c
new file mode 100644
index 0000000..788d947
--- /dev/null
+++ b/src/routines/section/global.c
@@ -0,0 +1,144 @@
+/*
+ * nanowasm, a tiny WebAssembly/Wasm interpreter
+ * Copyright (C) 2023-2024  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>
+
+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 = nwp_section_exit;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_global(struct nw_mod *const m)
+{
+    struct nw_sm_gl *const gl = &m->sm.global;
+    const struct nw_interp_cfg cfg =
+    {
+        .stack =
+        {
+            .buf = &gl->value,
+            .n = sizeof gl->value
+        },
+
+        .m = m,
+        .io = m->cfg.io
+    };
+
+    if (nwp_interp_start(&cfg, &nwp_interp_initexpr_set, &gl->interp))
+    {
+        LOG("%s: nw_interp_start failed\n", __func__);
+        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);
+
+    if (n)
+        return n;
+
+    m->next = get_global;
+    return NW_AGAIN;
+}
+
+static int get_type(const nw_varint7 content_type, enum nw_type *const out)
+{
+    static const struct type
+    {
+        nw_varint7 key;
+        enum nw_type value;
+    } list[] =
+    {
+        {.key = 0x7f, .value = NW_TYPE_I32},
+        {.key = 0x7e, .value = NW_TYPE_I64},
+        {.key = 0x7d, .value = NW_TYPE_F32},
+        {.key = 0x7c, .value = NW_TYPE_F64}
+    };
+
+    for (size_t i = 0; i < sizeof list / sizeof *list; i++)
+    {
+        const struct type *const t = &list[i];
+
+        if (content_type == t->key)
+        {
+            *out = t->value;
+            return 0;
+        }
+    }
+
+    LOG("%s: invalid type: %#hhx\n", __func__, (char)content_type);
+    return -1;
+}
+
+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);
+
+    if (n)
+        return n;
+    else if (get_type(content_type, &gl->type))
+    {
+        LOG("%s: get_type failed\n", __func__);
+        return NW_FATAL;
+    }
+
+    m->next = get_mutability;
+    return NW_AGAIN;
+}
+
+static enum nw_state entry_loop(struct nw_mod *const m)
+{
+    const struct nw_sm_gl *const gl = &m->sm.global;
+
+    m->next = gl->entry_i < m->global_count ?
+        get_content_type : nwp_section_exit;
+    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;
+    const enum nw_state n = nwp_varuint32(cfg, l, &m->global_count);
+
+    if (n)
+        return n;
+
+    m->next = entry_loop;
+    return NW_AGAIN;
+}
+
+void nwp_section_global(struct nw_mod *const m)
+{
+    m->next = get_count;
+    m->sm.global = (const struct nw_sm_gl){0};
+}