From 6d9d80362f9932bbc87e162b8ef7df06c73e27e1 Mon Sep 17 00:00:00 2001 From: Xavier Del Campo Romero Date: Sat, 7 Sep 2024 00:04:38 +0200 Subject: First commit --- src/routines/section/data.c | 178 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 178 insertions(+) create mode 100644 src/routines/section/data.c (limited to 'src/routines/section/data.c') diff --git a/src/routines/section/data.c b/src/routines/section/data.c new file mode 100644 index 0000000..b189c9d --- /dev/null +++ b/src/routines/section/data.c @@ -0,0 +1,178 @@ +/* + * 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 +#include +#include +#include +#include +#include + +static enum nw_state get_index(struct nw_mod *); + +static enum nw_state skip_bytes(struct nw_mod *const m) +{ + struct nw_sm_d *const d = &m->sm.data; + const struct nw_io_cfg *const cfg = &m->cfg.io; + const long offset = d->offset + d->size; + const enum nw_state n = cfg->seek(offset, cfg->user); + + if (n) + return n; + + m->next = ++d->entry_i >= m->data_count ? nwp_section_exit : get_index; + return NW_AGAIN; +} + +static enum nw_state tell(struct nw_mod *const m) +{ + const struct nw_io_cfg *const cfg = &m->cfg.io; + struct nw_sm_d *const d = &m->sm.data; + const enum nw_state n = cfg->tell(&d->offset, cfg->user); + + if (n) + return n; + + m->next = skip_bytes; + return NW_AGAIN; +} + +static enum nw_state get_size(struct nw_mod *const m) +{ + const struct nw_io_cfg *const cfg = &m->cfg.io; + struct nw_sm_d *const d = &m->sm.data; + struct nw_sm_leb128 *const l = &d->leb128; + const enum nw_state n = nwp_varuint32(cfg, l, &d->size, cfg->user); + + if (n) + return n; + else if (!d->size) + { +#ifdef NW_LOG + nwp_log("unexpected zero size for data entry %lu\n", + (unsigned long)d->entry_i); +#endif + return NW_FATAL; + } + + m->next = tell; + return NW_AGAIN; +} + +static int push(const void *const src, const size_t n, void *const user) +{ + struct nw_mod *const m = user; + struct nw_sm_d *const d = &m->sm.data; + + if (n > sizeof d->value) + { +#ifdef NW_LOG + nwp_log("stack overflow\n"); +#endif + return -1; + } + + memcpy(&d->value, src, n); + return n; +} + +static enum nw_state loop(struct nw_mod *const m) +{ + struct nw_sm_d *const d = &m->sm.data; + const enum nw_state n = nwp_interp_run(&d->interp); + + if (n) + return n; + + m->next = get_size; + return NW_AGAIN; +} + +static enum nw_state setup_initexpr(struct nw_mod *const m) +{ + struct nw_interp_cfg icfg = {0}; + struct nw_sm_d *const d = &m->sm.data; + + icfg.m = m; + icfg.io = m->cfg.io; + icfg.user = m; + icfg.stack.push = push; + + if (nwp_interp_start(&d->interp, &icfg, &nwp_interp_data_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_index(struct nw_mod *const m) +{ + const struct nw_io_cfg *const cfg = &m->cfg.io; + struct nw_sm_d *const d = &m->sm.data; + struct nw_sm_leb128 *const l = &d->leb128; + nw_varuint32 *const index = &d->index; + const enum nw_state n = nwp_varuint32(cfg, l, index, cfg->user); + + if (n) + return n; + else if (*index) + { +#ifdef NW_LOG + nwp_log("expected memory index 0 in data entry %lu, got %lu\n", + (unsigned long)d->entry_i, *index); +#endif + return NW_FATAL; + } + + return setup_initexpr(m); +} + +static enum nw_state get_count(struct nw_mod *const m) +{ + const struct nw_io_cfg *const cfg = &m->cfg.io; + const long dc = m->sections[NW_SECTION_DATA_COUNT]; + struct nw_sm_d *const d = &m->sm.data; + struct nw_sm_leb128 *const l = &d->leb128; + nw_varuint32 count, *const pcount = dc ? &count : &m->data_count; + enum nw_state n; + + if (!m->sections[NW_SECTION_MEMORY]) + { +#ifdef NW_LOG + nwp_log("data section found before memory section\n"); +#endif + return NW_FATAL; + } + else if ((n = nwp_varuint32(cfg, l, pcount, cfg->user))) + return n; + else if (dc && count != m->data_count) + { +#ifdef NW_LOG + nwp_log("data count mismatch, expected %lu, got %lu\n", + (unsigned long)m->data_count, (unsigned long)count); +#endif + return NW_FATAL; + } + + m->next = m->data_count ? get_index : nwp_section_exit; + return NW_AGAIN; +} + +void nwp_section_data(struct nw_mod *const m) +{ + const struct nw_sm_d d = {0}; + + m->sm.data = d; + m->next = get_count; +} -- cgit v1.2.3