| // Copyright 2020 The Wuffs Authors. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // https://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| // |
| // SPDX-License-Identifier: Apache-2.0 OR MIT |
| |
| // ---------------- Auxiliary - CBOR |
| |
| #if !defined(WUFFS_CONFIG__MODULES) || defined(WUFFS_CONFIG__MODULE__AUX__CBOR) |
| |
| #include <utility> |
| |
| namespace wuffs_aux { |
| |
| DecodeCborResult::DecodeCborResult(std::string&& error_message0, |
| uint64_t cursor_position0) |
| : error_message(std::move(error_message0)), |
| cursor_position(cursor_position0) {} |
| |
| DecodeCborCallbacks::~DecodeCborCallbacks() {} |
| |
| void // |
| DecodeCborCallbacks::Done(DecodeCborResult& result, |
| sync_io::Input& input, |
| IOBuffer& buffer) {} |
| |
| DecodeCborArgQuirks::DecodeCborArgQuirks(const QuirkKeyValuePair* ptr0, |
| const size_t len0) |
| : ptr(ptr0), len(len0) {} |
| |
| DecodeCborArgQuirks // |
| DecodeCborArgQuirks::DefaultValue() { |
| return DecodeCborArgQuirks(nullptr, 0); |
| } |
| |
| DecodeCborResult // |
| DecodeCbor(DecodeCborCallbacks& callbacks, |
| sync_io::Input& input, |
| DecodeCborArgQuirks quirks) { |
| // Prepare the wuffs_base__io_buffer and the resultant error_message. |
| wuffs_base__io_buffer* io_buf = input.BringsItsOwnIOBuffer(); |
| wuffs_base__io_buffer fallback_io_buf = wuffs_base__empty_io_buffer(); |
| std::unique_ptr<uint8_t[]> fallback_io_array(nullptr); |
| if (!io_buf) { |
| fallback_io_array = std::unique_ptr<uint8_t[]>(new uint8_t[4096]); |
| fallback_io_buf = wuffs_base__ptr_u8__writer(fallback_io_array.get(), 4096); |
| io_buf = &fallback_io_buf; |
| } |
| // cursor_index is discussed at |
| // https://nigeltao.github.io/blog/2020/jsonptr.html#the-cursor-index |
| size_t cursor_index = 0; |
| std::string ret_error_message; |
| std::string io_error_message; |
| |
| do { |
| // Prepare the low-level CBOR decoder. |
| wuffs_cbor__decoder::unique_ptr dec = wuffs_cbor__decoder::alloc(); |
| if (!dec) { |
| ret_error_message = "wuffs_aux::DecodeCbor: out of memory"; |
| goto done; |
| } |
| for (size_t i = 0; i < quirks.len; i++) { |
| dec->set_quirk(quirks.ptr[i].first, quirks.ptr[i].second); |
| } |
| |
| // Prepare the wuffs_base__tok_buffer. 256 tokens is 2KiB. |
| wuffs_base__token tok_array[256]; |
| wuffs_base__token_buffer tok_buf = |
| wuffs_base__slice_token__writer(wuffs_base__make_slice_token( |
| &tok_array[0], (sizeof(tok_array) / sizeof(tok_array[0])))); |
| wuffs_base__status tok_status = wuffs_base__make_status(nullptr); |
| |
| // Prepare other state. |
| int32_t depth = 0; |
| std::string str; |
| int64_t extension_category = 0; |
| uint64_t extension_detail = 0; |
| |
| // Valid token's VBCs range in 0 ..= 15. Values over that are for tokens |
| // from outside of the base package, such as the CBOR package. |
| constexpr int64_t EXT_CAT__CBOR_TAG = 16; |
| |
| // Loop, doing these two things: |
| // 1. Get the next token. |
| // 2. Process that token. |
| while (true) { |
| // 1. Get the next token. |
| |
| while (tok_buf.meta.ri >= tok_buf.meta.wi) { |
| if (tok_status.repr == nullptr) { |
| // No-op. |
| } else if (tok_status.repr == wuffs_base__suspension__short_write) { |
| tok_buf.compact(); |
| } else if (tok_status.repr == wuffs_base__suspension__short_read) { |
| // Read from input to io_buf. |
| if (!io_error_message.empty()) { |
| ret_error_message = std::move(io_error_message); |
| goto done; |
| } else if (cursor_index != io_buf->meta.ri) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad cursor_index"; |
| goto done; |
| } else if (io_buf->meta.closed) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: io_buf is closed"; |
| goto done; |
| } |
| io_buf->compact(); |
| if (io_buf->meta.wi >= io_buf->data.len) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: io_buf is full"; |
| goto done; |
| } |
| cursor_index = io_buf->meta.ri; |
| io_error_message = input.CopyIn(io_buf); |
| } else { |
| ret_error_message = tok_status.message(); |
| goto done; |
| } |
| |
| if (WUFFS_CBOR__DECODER_WORKBUF_LEN_MAX_INCL_WORST_CASE != 0) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad WORKBUF_LEN"; |
| goto done; |
| } |
| wuffs_base__slice_u8 work_buf = wuffs_base__empty_slice_u8(); |
| tok_status = dec->decode_tokens(&tok_buf, io_buf, work_buf); |
| if ((tok_buf.meta.ri > tok_buf.meta.wi) || |
| (tok_buf.meta.wi > tok_buf.data.len) || |
| (io_buf->meta.ri > io_buf->meta.wi) || |
| (io_buf->meta.wi > io_buf->data.len)) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad buffer indexes"; |
| goto done; |
| } |
| } |
| |
| wuffs_base__token token = tok_buf.data.ptr[tok_buf.meta.ri++]; |
| uint64_t token_len = token.length(); |
| if ((io_buf->meta.ri < cursor_index) || |
| ((io_buf->meta.ri - cursor_index) < token_len)) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad token indexes"; |
| goto done; |
| } |
| uint8_t* token_ptr = io_buf->data.ptr + cursor_index; |
| cursor_index += static_cast<size_t>(token_len); |
| |
| // 2. Process that token. |
| |
| uint64_t vbd = token.value_base_detail(); |
| |
| if (extension_category != 0) { |
| int64_t ext = token.value_extension(); |
| if ((ext >= 0) && !token.continued()) { |
| extension_detail = (extension_detail |
| << WUFFS_BASE__TOKEN__VALUE_EXTENSION__NUM_BITS) | |
| static_cast<uint64_t>(ext); |
| switch (extension_category) { |
| case WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_SIGNED: |
| extension_category = 0; |
| ret_error_message = |
| callbacks.AppendI64(static_cast<int64_t>(extension_detail)); |
| goto parsed_a_value; |
| case WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_UNSIGNED: |
| extension_category = 0; |
| ret_error_message = callbacks.AppendU64(extension_detail); |
| goto parsed_a_value; |
| case EXT_CAT__CBOR_TAG: |
| extension_category = 0; |
| ret_error_message = callbacks.AppendCborTag(extension_detail); |
| if (!ret_error_message.empty()) { |
| goto done; |
| } |
| continue; |
| } |
| } |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad extended token"; |
| goto done; |
| } |
| |
| switch (token.value_base_category()) { |
| case WUFFS_BASE__TOKEN__VBC__FILLER: |
| continue; |
| |
| case WUFFS_BASE__TOKEN__VBC__STRUCTURE: { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__PUSH) { |
| ret_error_message = callbacks.Push(static_cast<uint32_t>(vbd)); |
| if (!ret_error_message.empty()) { |
| goto done; |
| } |
| depth++; |
| if (depth > (int32_t)WUFFS_CBOR__DECODER_DEPTH_MAX_INCL) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad depth"; |
| goto done; |
| } |
| continue; |
| } |
| ret_error_message = callbacks.Pop(static_cast<uint32_t>(vbd)); |
| depth--; |
| if (depth < 0) { |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: bad depth"; |
| goto done; |
| } |
| goto parsed_a_value; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__STRING: { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__STRING__CONVERT_0_DST_1_SRC_DROP) { |
| // No-op. |
| } else if (vbd & |
| WUFFS_BASE__TOKEN__VBD__STRING__CONVERT_1_DST_1_SRC_COPY) { |
| const char* ptr = // Convert from (uint8_t*). |
| static_cast<const char*>(static_cast<void*>(token_ptr)); |
| str.append(ptr, static_cast<size_t>(token_len)); |
| } else { |
| goto fail; |
| } |
| if (token.continued()) { |
| continue; |
| } |
| ret_error_message = |
| (vbd & WUFFS_BASE__TOKEN__VBD__STRING__CHAIN_MUST_BE_UTF_8) |
| ? callbacks.AppendTextString(std::move(str)) |
| : callbacks.AppendByteString(std::move(str)); |
| str.clear(); |
| goto parsed_a_value; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__UNICODE_CODE_POINT: { |
| uint8_t u[WUFFS_BASE__UTF_8__BYTE_LENGTH__MAX_INCL]; |
| size_t n = wuffs_base__utf_8__encode( |
| wuffs_base__make_slice_u8( |
| &u[0], WUFFS_BASE__UTF_8__BYTE_LENGTH__MAX_INCL), |
| static_cast<uint32_t>(vbd)); |
| const char* ptr = // Convert from (uint8_t*). |
| static_cast<const char*>(static_cast<void*>(&u[0])); |
| str.append(ptr, n); |
| if (token.continued()) { |
| continue; |
| } |
| goto fail; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__LITERAL: { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__LITERAL__NULL) { |
| ret_error_message = callbacks.AppendNull(); |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__LITERAL__UNDEFINED) { |
| ret_error_message = callbacks.AppendUndefined(); |
| } else { |
| ret_error_message = callbacks.AppendBool( |
| vbd & WUFFS_BASE__TOKEN__VBD__LITERAL__TRUE); |
| } |
| goto parsed_a_value; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__NUMBER: { |
| const uint64_t cfp_fbbe_fifb = |
| WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_FLOATING_POINT | |
| WUFFS_BASE__TOKEN__VBD__NUMBER__FORMAT_BINARY_BIG_ENDIAN | |
| WUFFS_BASE__TOKEN__VBD__NUMBER__FORMAT_IGNORE_FIRST_BYTE; |
| if ((vbd & cfp_fbbe_fifb) == cfp_fbbe_fifb) { |
| double f; |
| switch (token_len) { |
| case 3: |
| f = wuffs_base__ieee_754_bit_representation__from_u16_to_f64( |
| wuffs_base__peek_u16be__no_bounds_check(token_ptr + 1)); |
| break; |
| case 5: |
| f = wuffs_base__ieee_754_bit_representation__from_u32_to_f64( |
| wuffs_base__peek_u32be__no_bounds_check(token_ptr + 1)); |
| break; |
| case 9: |
| f = wuffs_base__ieee_754_bit_representation__from_u64_to_f64( |
| wuffs_base__peek_u64be__no_bounds_check(token_ptr + 1)); |
| break; |
| default: |
| goto fail; |
| } |
| ret_error_message = callbacks.AppendF64(f); |
| goto parsed_a_value; |
| } |
| goto fail; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_SIGNED: { |
| if (token.continued()) { |
| extension_category = WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_SIGNED; |
| extension_detail = |
| static_cast<uint64_t>(token.value_base_detail__sign_extended()); |
| continue; |
| } |
| ret_error_message = |
| callbacks.AppendI64(token.value_base_detail__sign_extended()); |
| goto parsed_a_value; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_UNSIGNED: { |
| if (token.continued()) { |
| extension_category = |
| WUFFS_BASE__TOKEN__VBC__INLINE_INTEGER_UNSIGNED; |
| extension_detail = vbd; |
| continue; |
| } |
| ret_error_message = callbacks.AppendU64(vbd); |
| goto parsed_a_value; |
| } |
| } |
| |
| if (token.value_major() == WUFFS_CBOR__TOKEN_VALUE_MAJOR) { |
| uint64_t value_minor = token.value_minor(); |
| if (value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__MINUS_1_MINUS_X) { |
| if (token_len == 9) { |
| ret_error_message = callbacks.AppendMinus1MinusX( |
| wuffs_base__peek_u64be__no_bounds_check(token_ptr + 1)); |
| goto parsed_a_value; |
| } |
| } else if (value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__SIMPLE_VALUE) { |
| ret_error_message = |
| callbacks.AppendCborSimpleValue(static_cast<uint8_t>( |
| value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__DETAIL_MASK)); |
| goto parsed_a_value; |
| } else if (value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__TAG) { |
| if (token.continued()) { |
| extension_category = EXT_CAT__CBOR_TAG; |
| extension_detail = |
| value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__DETAIL_MASK; |
| continue; |
| } |
| ret_error_message = callbacks.AppendCborTag( |
| value_minor & WUFFS_CBOR__TOKEN_VALUE_MINOR__DETAIL_MASK); |
| if (!ret_error_message.empty()) { |
| goto done; |
| } |
| continue; |
| } |
| } |
| |
| fail: |
| ret_error_message = |
| "wuffs_aux::DecodeCbor: internal error: unexpected token"; |
| goto done; |
| |
| parsed_a_value: |
| if (!ret_error_message.empty() || (depth == 0)) { |
| goto done; |
| } |
| } |
| } while (false); |
| |
| done: |
| DecodeCborResult result( |
| std::move(ret_error_message), |
| wuffs_base__u64__sat_add(io_buf->meta.pos, cursor_index)); |
| callbacks.Done(result, input, *io_buf); |
| return result; |
| } |
| |
| } // namespace wuffs_aux |
| |
| #endif // !defined(WUFFS_CONFIG__MODULES) || |
| // defined(WUFFS_CONFIG__MODULE__AUX__CBOR) |
