| // 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 - JSON |
| |
| #if !defined(WUFFS_CONFIG__MODULES) || defined(WUFFS_CONFIG__MODULE__AUX__JSON) |
| |
| #include <utility> |
| |
| namespace wuffs_aux { |
| |
| DecodeJsonResult::DecodeJsonResult(std::string&& error_message0, |
| uint64_t cursor_position0) |
| : error_message(std::move(error_message0)), |
| cursor_position(cursor_position0) {} |
| |
| DecodeJsonCallbacks::~DecodeJsonCallbacks() {} |
| |
| void // |
| DecodeJsonCallbacks::Done(DecodeJsonResult& result, |
| sync_io::Input& input, |
| IOBuffer& buffer) {} |
| |
| const char DecodeJson_BadJsonPointer[] = |
| "wuffs_aux::DecodeJson: bad JSON Pointer"; |
| const char DecodeJson_NoMatch[] = "wuffs_aux::DecodeJson: no match"; |
| |
| // -------- |
| |
| #define WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN \ |
| while (tok_buf.meta.ri >= tok_buf.meta.wi) { \ |
| if (tok_status.repr == nullptr) { \ |
| } else if (tok_status.repr == wuffs_base__suspension__short_write) { \ |
| tok_buf.compact(); \ |
| } else if (tok_status.repr == wuffs_base__suspension__short_read) { \ |
| 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::DecodeJson: internal error: bad cursor_index"; \ |
| goto done; \ |
| } else if (io_buf->meta.closed) { \ |
| ret_error_message = \ |
| "wuffs_aux::DecodeJson: 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::DecodeJson: 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_JSON__DECODER_WORKBUF_LEN_MAX_INCL_WORST_CASE != 0) { \ |
| ret_error_message = \ |
| "wuffs_aux::DecodeJson: 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::DecodeJson: internal error: bad token indexes"; \ |
| goto done; \ |
| } \ |
| uint8_t* token_ptr = io_buf->data.ptr + cursor_index; \ |
| (void)(token_ptr); \ |
| cursor_index += static_cast<size_t>(token_len) |
| |
| // -------- |
| |
| namespace { |
| |
| // DecodeJson_SplitJsonPointer returns ("bar", 8) for ("/foo/bar/b~1z/qux", 5, |
| // etc). It returns a 0 size_t when s has invalid JSON Pointer syntax. |
| // |
| // The string returned is unescaped. If calling it again, this time with i=8, |
| // the "b~1z" substring would be returned as "b/z". |
| std::pair<std::string, size_t> // |
| DecodeJson_SplitJsonPointer(std::string& s, |
| size_t i, |
| bool allow_tilde_n_tilde_r_tilde_t) { |
| std::string fragment; |
| while (i < s.size()) { |
| char c = s[i]; |
| if (c == '/') { |
| break; |
| } else if (c != '~') { |
| fragment.push_back(c); |
| i++; |
| continue; |
| } |
| i++; |
| if (i >= s.size()) { |
| return std::make_pair(std::string(), 0); |
| } |
| c = s[i]; |
| if (c == '0') { |
| fragment.push_back('~'); |
| i++; |
| continue; |
| } else if (c == '1') { |
| fragment.push_back('/'); |
| i++; |
| continue; |
| } else if (allow_tilde_n_tilde_r_tilde_t) { |
| if (c == 'n') { |
| fragment.push_back('\n'); |
| i++; |
| continue; |
| } else if (c == 'r') { |
| fragment.push_back('\r'); |
| i++; |
| continue; |
| } else if (c == 't') { |
| fragment.push_back('\t'); |
| i++; |
| continue; |
| } |
| } |
| return std::make_pair(std::string(), 0); |
| } |
| return std::make_pair(std::move(fragment), i); |
| } |
| |
| // -------- |
| |
| std::string // |
| DecodeJson_WalkJsonPointerFragment(wuffs_base__token_buffer& tok_buf, |
| wuffs_base__status& tok_status, |
| wuffs_json__decoder::unique_ptr& dec, |
| wuffs_base__io_buffer* io_buf, |
| std::string& io_error_message, |
| size_t& cursor_index, |
| sync_io::Input& input, |
| std::string& json_pointer_fragment) { |
| std::string ret_error_message; |
| while (true) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| if (vbc == WUFFS_BASE__TOKEN__VBC__FILLER) { |
| continue; |
| } else if ((vbc != WUFFS_BASE__TOKEN__VBC__STRUCTURE) || |
| !(vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__PUSH)) { |
| return DecodeJson_NoMatch; |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__TO_LIST) { |
| goto do_list; |
| } |
| goto do_dict; |
| } |
| |
| do_dict: |
| // Alternate between these two things: |
| // 1. Decode the next dict key (a string). If it matches the fragment, we're |
| // done (success). If we've reached the dict's end (VBD__STRUCTURE__POP) |
| // so that there was no next dict key, we're done (failure). |
| // 2. Otherwise, skip the next dict value. |
| while (true) { |
| for (std::string str; true;) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| switch (vbc) { |
| case WUFFS_BASE__TOKEN__VBC__FILLER: |
| continue; |
| |
| case WUFFS_BASE__TOKEN__VBC__STRUCTURE: |
| if (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__PUSH) { |
| goto fail; |
| } |
| return DecodeJson_NoMatch; |
| |
| 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; |
| } |
| break; |
| } |
| |
| 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); |
| break; |
| } |
| |
| default: |
| goto fail; |
| } |
| |
| if (token.continued()) { |
| continue; |
| } |
| if (str == json_pointer_fragment) { |
| return ""; |
| } |
| goto skip_the_next_dict_value; |
| } |
| |
| skip_the_next_dict_value: |
| for (uint32_t skip_depth = 0; true;) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| if (token.continued() || (vbc == WUFFS_BASE__TOKEN__VBC__FILLER)) { |
| continue; |
| } else if (vbc == WUFFS_BASE__TOKEN__VBC__STRUCTURE) { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__PUSH) { |
| skip_depth++; |
| continue; |
| } |
| skip_depth--; |
| } |
| |
| if (skip_depth == 0) { |
| break; |
| } |
| } // skip_the_next_dict_value |
| } // do_dict |
| |
| do_list: |
| do { |
| wuffs_base__result_u64 result_u64 = wuffs_base__parse_number_u64( |
| wuffs_base__make_slice_u8( |
| static_cast<uint8_t*>(static_cast<void*>( |
| const_cast<char*>(json_pointer_fragment.data()))), |
| json_pointer_fragment.size()), |
| WUFFS_BASE__PARSE_NUMBER_XXX__DEFAULT_OPTIONS); |
| if (!result_u64.status.is_ok()) { |
| return DecodeJson_NoMatch; |
| } |
| uint64_t remaining = result_u64.value; |
| if (remaining == 0) { |
| goto check_that_a_value_follows; |
| } |
| for (uint32_t skip_depth = 0; true;) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| if (token.continued() || (vbc == WUFFS_BASE__TOKEN__VBC__FILLER)) { |
| continue; |
| } else if (vbc == WUFFS_BASE__TOKEN__VBC__STRUCTURE) { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__PUSH) { |
| skip_depth++; |
| continue; |
| } |
| if (skip_depth == 0) { |
| return DecodeJson_NoMatch; |
| } |
| skip_depth--; |
| } |
| |
| if (skip_depth > 0) { |
| continue; |
| } |
| remaining--; |
| if (remaining == 0) { |
| goto check_that_a_value_follows; |
| } |
| } |
| } while (false); // do_list |
| |
| check_that_a_value_follows: |
| while (true) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| if (vbc == WUFFS_BASE__TOKEN__VBC__FILLER) { |
| continue; |
| } |
| |
| // Undo the last part of WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN, so that |
| // we're only peeking at the next token. |
| tok_buf.meta.ri--; |
| cursor_index -= static_cast<size_t>(token_len); |
| |
| if ((vbc == WUFFS_BASE__TOKEN__VBC__STRUCTURE) && |
| (vbd & WUFFS_BASE__TOKEN__VBD__STRUCTURE__POP)) { |
| return DecodeJson_NoMatch; |
| } |
| return ""; |
| } // check_that_a_value_follows |
| |
| fail: |
| return "wuffs_aux::DecodeJson: internal error: unexpected token"; |
| done: |
| return ret_error_message; |
| } |
| |
| } // namespace |
| |
| // -------- |
| |
| DecodeJsonResult // |
| DecodeJson(DecodeJsonCallbacks& callbacks, |
| sync_io::Input& input, |
| wuffs_base__slice_u32 quirks, |
| std::string json_pointer) { |
| // 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 JSON decoder. |
| wuffs_json__decoder::unique_ptr dec = wuffs_json__decoder::alloc(); |
| if (!dec) { |
| ret_error_message = "wuffs_aux::DecodeJson: out of memory"; |
| goto done; |
| } |
| bool allow_tilde_n_tilde_r_tilde_t = false; |
| for (size_t i = 0; i < quirks.len; i++) { |
| dec->set_quirk_enabled(quirks.ptr[i], true); |
| if (quirks.ptr[i] == |
| WUFFS_JSON__QUIRK_JSON_POINTER_ALLOW_TILDE_N_TILDE_R_TILDE_T) { |
| allow_tilde_n_tilde_r_tilde_t = 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; |
| |
| // Walk the (optional) JSON Pointer. |
| for (size_t i = 0; i < json_pointer.size();) { |
| if (json_pointer[i] != '/') { |
| ret_error_message = DecodeJson_BadJsonPointer; |
| goto done; |
| } |
| std::pair<std::string, size_t> split = DecodeJson_SplitJsonPointer( |
| json_pointer, i + 1, allow_tilde_n_tilde_r_tilde_t); |
| i = std::move(split.second); |
| if (i == 0) { |
| ret_error_message = DecodeJson_BadJsonPointer; |
| goto done; |
| } |
| ret_error_message = DecodeJson_WalkJsonPointerFragment( |
| tok_buf, tok_status, dec, io_buf, io_error_message, cursor_index, |
| input, split.first); |
| if (!ret_error_message.empty()) { |
| goto done; |
| } |
| } |
| |
| // Loop, doing these two things: |
| // 1. Get the next token. |
| // 2. Process that token. |
| while (true) { |
| WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN; |
| |
| int64_t vbc = token.value_base_category(); |
| uint64_t vbd = token.value_base_detail(); |
| switch (vbc) { |
| 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 = callbacks.AppendTextString(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: { |
| ret_error_message = |
| (vbd & WUFFS_BASE__TOKEN__VBD__LITERAL__NULL) |
| ? callbacks.AppendNull() |
| : callbacks.AppendBool(vbd & |
| WUFFS_BASE__TOKEN__VBD__LITERAL__TRUE); |
| goto parsed_a_value; |
| } |
| |
| case WUFFS_BASE__TOKEN__VBC__NUMBER: { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__FORMAT_TEXT) { |
| if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_INTEGER_SIGNED) { |
| wuffs_base__result_i64 r = wuffs_base__parse_number_i64( |
| wuffs_base__make_slice_u8(token_ptr, |
| static_cast<size_t>(token_len)), |
| WUFFS_BASE__PARSE_NUMBER_XXX__DEFAULT_OPTIONS); |
| if (r.status.is_ok()) { |
| ret_error_message = callbacks.AppendI64(r.value); |
| goto parsed_a_value; |
| } |
| } |
| if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_FLOATING_POINT) { |
| wuffs_base__result_f64 r = wuffs_base__parse_number_f64( |
| wuffs_base__make_slice_u8(token_ptr, |
| static_cast<size_t>(token_len)), |
| WUFFS_BASE__PARSE_NUMBER_XXX__DEFAULT_OPTIONS); |
| if (r.status.is_ok()) { |
| ret_error_message = callbacks.AppendF64(r.value); |
| goto parsed_a_value; |
| } |
| } |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_NEG_INF) { |
| ret_error_message = callbacks.AppendF64( |
| wuffs_base__ieee_754_bit_representation__from_u64_to_f64( |
| 0xFFF0000000000000ul)); |
| goto parsed_a_value; |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_POS_INF) { |
| ret_error_message = callbacks.AppendF64( |
| wuffs_base__ieee_754_bit_representation__from_u64_to_f64( |
| 0x7FF0000000000000ul)); |
| goto parsed_a_value; |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_NEG_NAN) { |
| ret_error_message = callbacks.AppendF64( |
| wuffs_base__ieee_754_bit_representation__from_u64_to_f64( |
| 0xFFFFFFFFFFFFFFFFul)); |
| goto parsed_a_value; |
| } else if (vbd & WUFFS_BASE__TOKEN__VBD__NUMBER__CONTENT_POS_NAN) { |
| ret_error_message = callbacks.AppendF64( |
| wuffs_base__ieee_754_bit_representation__from_u64_to_f64( |
| 0x7FFFFFFFFFFFFFFFul)); |
| goto parsed_a_value; |
| } |
| goto fail; |
| } |
| } |
| |
| fail: |
| ret_error_message = |
| "wuffs_aux::DecodeJson: internal error: unexpected token"; |
| goto done; |
| |
| parsed_a_value: |
| if (!ret_error_message.empty() || (depth == 0)) { |
| goto done; |
| } |
| } |
| } while (false); |
| |
| done: |
| DecodeJsonResult 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; |
| } |
| |
| #undef WUFFS_AUX__DECODE_JSON__GET_THE_NEXT_TOKEN |
| |
| } // namespace wuffs_aux |
| |
| #endif // !defined(WUFFS_CONFIG__MODULES) || |
| // defined(WUFFS_CONFIG__MODULE__AUX__JSON) |
