blob: 3beba20e96b1e0e3ebcd4d4c371284995f33a466 [file] [log] [blame]
// After editing this file, run "go generate" in the ../data directory.
// Copyright 2020 The Wuffs Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ---------------- 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) {}
DecodeCborResult //
DecodeCbor(DecodeCborCallbacks& callbacks,
sync_io::Input& input,
wuffs_base__slice_u32 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::CborDecoder: out of memory";
goto done;
}
for (size_t i = 0; i < quirks.len; i++) {
dec->set_quirk_enabled(quirks.ptr[i], true);
}
// 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.
uint32_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::CborDecoder: internal error: bad cursor_index";
goto done;
} else if (io_buf->meta.closed) {
ret_error_message =
"wuffs_aux::CborDecoder: 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::CborDecoder: 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::CborDecoder: 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);
}
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::CborDecoder: 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::CborDecoder: 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++;
continue;
}
ret_error_message = callbacks.Pop(static_cast<uint32_t>(vbd));
depth--;
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::CborDecoder: 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)