First commit

1 files changed, 196 insertions, 0 deletions

diff --git a/src/routines/init_data.c b/src/routines/init_data.c
new file mode 100644
index 0000000..c9482a0
--- /dev/null
+++ b/src/routines/init_data.c
@@ -0,0 +1,196 @@
+/*
+ * 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 <nanowasm/types.h>
+#include <nw/linear.h>
+#include <nw/interp.h>
+#include <nw/io.h>
+#include <nw/log.h>
+#include <nw/routines.h>
+#include <nw/stack.h>
+#include <nw/types.h>
+
+static enum nw_state get_index(struct nw_inst *);
+static enum nw_state get_byte(struct nw_inst *);
+
+static enum nw_state store_byte(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    struct nw_interp *const i = &inst->interp;
+    const unsigned long offset = d->offset + d->bytes_i;
+    const enum nw_state n = nwp_linear_store(i, &d->io, offset);
+
+    if (n)
+        return n;
+    else if (++d->bytes_i >= d->size)
+        inst->next = ++d->entry_i >= d->count ? d->next : get_index;
+    else
+        inst->next = get_byte;
+
+    return NW_AGAIN;
+}
+
+static enum nw_state get_byte(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    struct nw_interp *const i = &inst->interp;
+    const struct nw_io_cfg *const cfg = &i->cfg.io;
+    struct nw_sm_io io = {0};
+    enum nw_state n;
+
+    io.buf = &d->b;
+    io.n = sizeof d->b;
+
+    if ((n = nwp_io_read(cfg, &io, cfg->user)))
+        return n;
+    else
+    {
+        struct nw_sm_io io = {0};
+
+        io.buf = &d->b;
+        io.n = sizeof d->b;
+        d->io = io;
+    }
+
+    inst->next = store_byte;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_size(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    struct nw_sm_leb128 *const l = &d->leb128;
+    struct nw_interp *const i = &inst->interp;
+    const struct nw_io_cfg *const cfg = &i->cfg.io;
+    const enum nw_state n = nwp_varuint32(cfg, l, &d->size, cfg->user);
+
+    if (n)
+        return n;
+
+    d->bytes_i = 0;
+    inst->next = get_byte;
+    return NW_AGAIN;
+}
+
+static enum nw_state pop(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    const enum nw_state n = nwp_stack_pop(&inst->interp, &d->io);
+
+    if (n)
+        return n;
+
+    inst->next = get_size;
+    return NW_AGAIN;
+}
+
+static enum nw_state loop(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    const enum nw_state n = nwp_interp_run(&inst->interp);
+    struct nw_sm_io io = {0};
+
+    if (n)
+        return n;
+
+    io.buf = &d->offset;
+    io.n = sizeof d->offset;
+    d->io = io;
+    inst->next = pop;
+    return NW_AGAIN;
+}
+
+static enum nw_state setup_initexpr(struct nw_inst *const inst)
+{
+    struct nw_interp *const i = &inst->interp;
+    const struct nw_interp_cfg icfg = i->cfg;
+
+    if (nwp_interp_start(i, &icfg, &nwp_interp_data_set))
+    {
+#ifdef NW_LOG
+        nwp_log("nw_interp_start failed\n");
+#endif
+        return NW_FATAL;
+    }
+
+    inst->next = loop;
+    return NW_AGAIN;
+}
+
+static enum nw_state get_index(struct nw_inst *const inst)
+{
+    struct nw_inst_sm_d *const d = &inst->sm.data;
+    struct nw_sm_leb128 *const l = &d->leb128;
+    struct nw_interp *const i = &inst->interp;
+    const struct nw_io_cfg *const cfg = &i->cfg.io;
+    const enum nw_state n = nwp_varuint32(cfg, l, &d->index, cfg->user);
+
+    if (n)
+        return n;
+
+    return setup_initexpr(inst);
+}
+
+static enum nw_state get_count(struct nw_inst *const i)
+{
+    struct nw_inst_sm_d *const d = &i->sm.data;
+    struct nw_sm_leb128 *const l = &d->leb128;
+    const struct nw_interp_cfg *const icfg = &i->interp.cfg;
+    const struct nw_io_cfg *const cfg = &icfg->io;
+    const nw_varuint32 expected = icfg->m->data_count;
+    const enum nw_state n = nwp_varuint32(cfg, l, &d->count, cfg->user);
+
+    if (n)
+        return n;
+    else if (d->count != expected)
+    {
+#ifdef NW_LOG
+        static const char *const exc = "data count mismatch";
+
+        nwp_log("%s, expected %lu, got %lu\n", exc,
+            (unsigned long)expected, (unsigned long)d->count);
+#endif
+        return NW_FATAL;
+    }
+
+    i->next = d->count ? get_index : d->next;
+    return NW_AGAIN;
+}
+
+static enum nw_state seek_data(struct nw_inst *const i)
+{
+    struct nw_inst_sm_gl *const d = &i->sm.global;
+    const struct nw_interp_cfg *const icfg = &i->interp.cfg;
+    const struct nw_io_cfg *const cfg = &icfg->io;
+    const long offset = icfg->m->sections[NW_SECTION_DATA];
+    enum nw_state n;
+
+    if (!offset)
+    {
+        i->next = d->next;
+        return NW_AGAIN;
+    }
+    else if ((n = cfg->seek(offset, cfg->user)))
+        return n;
+
+    i->next = get_count;
+    return NW_AGAIN;
+}
+
+void nwp_init_data(struct nw_inst *const i,
+    enum nw_state (*const next)(struct nw_inst *))
+{
+    const struct nw_inst_sm_d d = {0};
+    struct nw_inst_sm_d *const p = &i->sm.data;
+
+    *p = d;
+    p->next = next;
+    i->next = seek_data;
+}