Source/WebCore/Modules/fetch/FetchBodyConsumer.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2016 Apple Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted, provided that the following conditions
  * are required to be met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  * 3.  Neither the name of Apple Inc. nor the names of
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS "AS IS" AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE INC. AND ITS CONTRIBUTORS BE LIABLE FOR
  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "FetchBodyConsumer.h"

 #include "DOMFormData.h"
 #include "FormData.h"
 #include "FormDataConsumer.h"
 #include "HTTPHeaderField.h"
 #include "HTTPParsers.h"
 #include "JSBlob.h"
 #include "JSDOMFormData.h"
 #include "TextResourceDecoder.h"
 #include <wtf/StringExtras.h>
 #include <wtf/URLParser.h>

 namespace WebCore {

 static inline Ref<Blob> blobFromData(ScriptExecutionContext* context, Vector<uint8_t>&& data, const String& contentType)
 {
     return Blob::create(context, WTFMove(data), Blob::normalizedContentType(contentType));
 }

 // https://mimesniff.spec.whatwg.org/#http-quoted-string-token-code-point
 static bool isHTTPQuotedStringTokenCodePoint(UChar c)
 {
     return c == 0x09
         || (c >= 0x20 && c <= 0x7E)
         || (c >= 0x80 && c <= 0xFF);
 }

 struct MimeType {
     String type;
     String subtype;
     HashMap<String, String> parameters;
 };

 static HashMap<String, String> parseParameters(StringView input, size_t position)
 {
     HashMap<String, String> parameters;
     while (position < input.length()) {
         while (position < input.length() && RFC7230::isWhitespace(input[position]))
             position++;
         size_t nameBegin = position;
         while (position < input.length() && input[position] != '=' && input[position] != ';')
             position++;
         if (position >= input.length())
             break;
         if (input[position] == ';') {
             position++;
             continue;
         }
         StringView parameterName = input.substring(nameBegin, position - nameBegin);
         position++;
         if (position >= input.length())
             break;

         StringView parameterValue;
         if (position < input.length() && input[position] == '"') {
             position++;
             size_t valueBegin = position;
             while (position < input.length() && input[position] != '"')
                 position++;
             parameterValue = input.substring(valueBegin, position - valueBegin);
             position++;
         } else {
             size_t valueBegin = position;
             while (position < input.length() && input[position] != ';')
                 position++;
             parameterValue = stripLeadingAndTrailingHTTPSpaces(input.substring(valueBegin, position - valueBegin));
         }

         if (parameterName.length()
             && isValidHTTPToken(parameterName)
             && parameterValue.isAllSpecialCharacters<isHTTPQuotedStringTokenCodePoint>()) {
             parameters.ensure(parameterName.toString(), [&] { return parameterValue.toString(); });
         }
     }
     return parameters;
 }

 // https://mimesniff.spec.whatwg.org/#parsing-a-mime-type
 static std::optional<MimeType> parseMIMEType(const String& contentType)
 {
     String input = stripLeadingAndTrailingHTTPSpaces(contentType);
     size_t slashIndex = input.find('/');
     if (slashIndex == notFound)
         return std::nullopt;

     String type = input.left(slashIndex);
     if (!type.length() || !isValidHTTPToken(type))
         return std::nullopt;

     size_t semicolonIndex = input.find(';', slashIndex);
     String subtype = stripLeadingAndTrailingHTTPSpaces(input.substring(slashIndex + 1, semicolonIndex - slashIndex - 1));
     if (!subtype.length() || !isValidHTTPToken(subtype))
         return std::nullopt;

     return {{ WTFMove(type), WTFMove(subtype), parseParameters(StringView(input), semicolonIndex + 1) }};
 }

 // https://fetch.spec.whatwg.org/#concept-body-package-data
 RefPtr<DOMFormData> FetchBodyConsumer::packageFormData(ScriptExecutionContext* context, const String& contentType, const uint8_t* data, size_t length)
 {
     auto parseMultipartPart = [context] (const uint8_t* part, size_t partLength, DOMFormData& form) -> bool {
         const uint8_t* headerEnd = static_cast<const uint8_t*>(memmem(part, partLength, "\r\n\r\n", 4));
         if (!headerEnd)
             return false;
         const uint8_t* headerBegin = part;
         size_t headerLength = headerEnd - headerBegin;

         const uint8_t* bodyBegin = headerEnd + strlen("\r\n\r\n");
         size_t bodyLength = partLength - (bodyBegin - headerBegin);

         String header = String::fromUTF8(headerBegin, headerLength);

         constexpr auto contentDispositionCharacters = "Content-Disposition:"_s;
         size_t contentDispositionBegin = header.find(contentDispositionCharacters);
         if (contentDispositionBegin == notFound)
             return false;
         size_t contentDispositionEnd = header.find("\r\n"_s, contentDispositionBegin);
         size_t contentDispositionParametersBegin = header.find(';', contentDispositionBegin + contentDispositionCharacters.length());
         if (contentDispositionParametersBegin != notFound)
             contentDispositionParametersBegin++;

         auto parameters = parseParameters(StringView(header).substring(contentDispositionParametersBegin, contentDispositionEnd - contentDispositionParametersBegin), 0);
         String name = parameters.get<HashTranslatorASCIILiteral>("name"_s);
         if (!name)
             return false;
         String filename = parameters.get<HashTranslatorASCIILiteral>("filename"_s);
         if (!filename)
             form.append(name, String::fromUTF8(bodyBegin, bodyLength));
         else {
             String contentType = "text/plain"_s;

             constexpr auto contentTypeCharacters = "Content-Type:"_s;
             size_t contentTypePrefixLength = contentTypeCharacters.length();
             size_t contentTypeBegin = header.find(contentTypeCharacters);
             if (contentTypeBegin != notFound) {
                 size_t contentTypeEnd = header.find("\r\n"_s, contentTypeBegin);
                 contentType = StringView(header).substring(contentTypeBegin + contentTypePrefixLength, contentTypeEnd - contentTypeBegin - contentTypePrefixLength).stripLeadingAndTrailingMatchedCharacters(isHTTPSpace).toString();
             }

             form.append(name, File::create(context, Blob::create(context, Vector { bodyBegin, bodyLength }, Blob::normalizedContentType(contentType)).get(), filename).get(), filename);
         }
         return true;
     };

     auto parseMultipartBoundary = [] (const std::optional<MimeType>& mimeType) -> std::optional<String> {
         if (!mimeType)
             return std::nullopt;
         if (equalLettersIgnoringASCIICase(mimeType->type, "multipart"_s) && equalLettersIgnoringASCIICase(mimeType->subtype, "form-data"_s)) {
             auto iterator = mimeType->parameters.find<HashTranslatorASCIILiteral>("boundary"_s);
             if (iterator != mimeType->parameters.end())
                 return iterator->value;
         }
         return std::nullopt;
     };

     auto form = DOMFormData::create(PAL::UTF8Encoding());
     auto mimeType = parseMIMEType(contentType);
     if (auto multipartBoundary = parseMultipartBoundary(mimeType)) {
         auto boundaryWithDashes = makeString("--", *multipartBoundary);
         CString boundary = boundaryWithDashes.utf8();
         size_t boundaryLength = boundary.length();

         const uint8_t* currentBoundary = static_cast<const uint8_t*>(memmem(data, length, boundary.data(), boundaryLength));
         if (!currentBoundary)
             return nullptr;
         const uint8_t* nextBoundary = static_cast<const uint8_t*>(memmem(currentBoundary + boundaryLength, length - (currentBoundary + boundaryLength - data), boundary.data(), boundaryLength));
         if (!nextBoundary)
             return nullptr;
         while (nextBoundary) {
             parseMultipartPart(currentBoundary + boundaryLength, nextBoundary - currentBoundary - boundaryLength - strlen("\r\n"), form.get());
             currentBoundary = nextBoundary;
             nextBoundary = static_cast<const uint8_t*>(memmem(nextBoundary + boundaryLength, length - (nextBoundary + boundaryLength - data), boundary.data(), boundaryLength));
         }
     } else if (mimeType && equalLettersIgnoringASCIICase(mimeType->type, "application"_s) && equalLettersIgnoringASCIICase(mimeType->subtype, "x-www-form-urlencoded"_s)) {
         auto dataString = String::fromUTF8(data, length);
         for (auto& pair : WTF::URLParser::parseURLEncodedForm(dataString))
             form->append(pair.key, pair.value);
     } else
         return nullptr;

     return form;
 }

 static void resolveWithTypeAndData(Ref<DeferredPromise>&& promise, FetchBodyConsumer::Type type, const String& contentType, const unsigned char* data, unsigned length)
 {
     auto* context = promise->scriptExecutionContext();

     switch (type) {
     case FetchBodyConsumer::Type::ArrayBuffer:
         fulfillPromiseWithArrayBuffer(WTFMove(promise), data, length);
         return;
     case FetchBodyConsumer::Type::Blob:
         promise->resolveCallbackValueWithNewlyCreated<IDLInterface<Blob>>([&data, &length, &contentType, context](auto&) {
             return blobFromData(context, { data, length }, contentType);
         });
         return;
     case FetchBodyConsumer::Type::JSON:
         fulfillPromiseWithJSON(WTFMove(promise), TextResourceDecoder::textFromUTF8(data, length));
         return;
     case FetchBodyConsumer::Type::Text:
         promise->resolve<IDLDOMString>(TextResourceDecoder::textFromUTF8(data, length));
         return;
     case FetchBodyConsumer::Type::FormData:
         if (auto formData = FetchBodyConsumer::packageFormData(context, contentType, data, length))
             promise->resolve<IDLInterface<DOMFormData>>(*formData);
         else
             promise->reject(TypeError);
         return;
     case FetchBodyConsumer::Type::None:
         ASSERT_NOT_REACHED();
         return;
     }
 }

 void FetchBodyConsumer::clean()
 {
     m_buffer.reset();
     if (m_formDataConsumer)
         m_formDataConsumer->cancel();
     resetConsumePromise();
     if (m_sink) {
         m_sink->clearCallback();
         return;
     }
 }

 void FetchBodyConsumer::resolveWithData(Ref<DeferredPromise>&& promise, const String& contentType, const unsigned char* data, unsigned length)
 {
     resolveWithTypeAndData(WTFMove(promise), m_type, contentType, data, length);
 }

 void FetchBodyConsumer::resolveWithFormData(Ref<DeferredPromise>&& promise, const String& contentType, const FormData& formData, ScriptExecutionContext* context)
 {
     if (auto sharedBuffer = formData.asSharedBuffer()) {
         resolveWithData(WTFMove(promise), contentType, sharedBuffer->makeContiguous()->data(), sharedBuffer->size());
         return;
     }

     if (!context)
         return;

     m_formDataConsumer = makeUnique<FormDataConsumer>(formData, *context, [this, capturedPromise = WTFMove(promise), contentType, builder = SharedBufferBuilder { }](auto&& result) mutable {
         if (result.hasException()) {
             auto promise = WTFMove(capturedPromise);
             promise->reject(result.releaseException());
             return;
         }

         auto& value = result.returnValue();
         if (value.empty()) {
             auto buffer = builder.takeAsContiguous();
             resolveWithData(WTFMove(capturedPromise), contentType, buffer->data(), buffer->size());
             return;
         }

         builder.append(value);
     });
 }

 void FetchBodyConsumer::consumeFormDataAsStream(const FormData& formData, FetchBodySource& source, ScriptExecutionContext* context)
 {
     if (auto sharedBuffer = formData.asSharedBuffer()) {
         if (source.enqueue(ArrayBuffer::tryCreate(sharedBuffer->makeContiguous()->data(), sharedBuffer->size())))
             source.close();
         return;
     }

     if (!context)
         return;

     m_formDataConsumer = makeUnique<FormDataConsumer>(formData, *context, [this, source = Ref { source }](auto&& result) {
         if (result.hasException()) {
             source->error(result.releaseException());
             return;
         }

         auto& value = result.returnValue();
         if (value.empty()) {
             source->close();
             return;
         }

         if (!source->enqueue(ArrayBuffer::tryCreate(value.data(), value.size())))
             m_formDataConsumer->cancel();
     });
 }

 void FetchBodyConsumer::extract(ReadableStream& stream, ReadableStreamToSharedBufferSink::Callback&& callback)
 {
     ASSERT(!m_sink);
     m_sink = ReadableStreamToSharedBufferSink::create(WTFMove(callback));
     m_sink->pipeFrom(stream);
 }

 void FetchBodyConsumer::resolve(Ref<DeferredPromise>&& promise, const String& contentType, ReadableStream* stream)
 {
     if (stream) {
         ASSERT(!m_sink);
         m_sink = ReadableStreamToSharedBufferSink::create([promise = WTFMove(promise), data = SharedBufferBuilder(), type = m_type, contentType](auto&& result) mutable {
             if (result.hasException()) {
                 promise->reject(result.releaseException());
                 return;
             }

             if (auto* chunk = result.returnValue())
                 data.append(chunk->data(), chunk->size());
             else {
                 auto buffer = data.takeAsContiguous();
                 resolveWithTypeAndData(WTFMove(promise), type, contentType, buffer->data(), buffer->size());
             }
         });
         m_sink->pipeFrom(*stream);
         return;
     }

     if (m_isLoading) {
         setConsumePromise(WTFMove(promise));
         return;
     }

     auto* context = promise->scriptExecutionContext();

     ASSERT(m_type != Type::None);
     switch (m_type) {
     case Type::ArrayBuffer:
         fulfillPromiseWithArrayBuffer(WTFMove(promise), takeAsArrayBuffer().get());
         return;
     case Type::Blob:
         promise->resolveCallbackValueWithNewlyCreated<IDLInterface<Blob>>([this, context](auto&) {
             return takeAsBlob(context);
         });
         return;
     case Type::JSON:
         fulfillPromiseWithJSON(WTFMove(promise), takeAsText());
         return;
     case Type::Text:
         promise->resolve<IDLDOMString>(takeAsText());
         return;
     case FetchBodyConsumer::Type::FormData: {
         auto buffer = takeData();
         if (auto formData = packageFormData(context, contentType, buffer ? buffer->makeContiguous()->data() : nullptr, buffer ? buffer->size() : 0))
             promise->resolve<IDLInterface<DOMFormData>>(*formData);
         else
             promise->reject(TypeError);
         return;
     }
     case Type::None:
         ASSERT_NOT_REACHED();
         return;
     }
 }

 void FetchBodyConsumer::append(const SharedBuffer& buffer)
 {
     if (m_source) {
         m_source->enqueue(buffer.tryCreateArrayBuffer());
         return;
     }
     m_buffer.append(buffer);
 }

 void FetchBodyConsumer::setData(Ref<FragmentedSharedBuffer>&& data)
 {
     m_buffer = WTFMove(data);
 }

 RefPtr<FragmentedSharedBuffer> FetchBodyConsumer::takeData()
 {
     if (!m_buffer)
         return nullptr;
     return m_buffer.take();
 }

 RefPtr<JSC::ArrayBuffer> FetchBodyConsumer::takeAsArrayBuffer()
 {
     return m_buffer.takeAsArrayBuffer();
 }

 Ref<Blob> FetchBodyConsumer::takeAsBlob(ScriptExecutionContext* context)
 {
     if (!m_buffer)
         return Blob::create(context, Vector<uint8_t>(), Blob::normalizedContentType(m_contentType));

     return blobFromData(context, m_buffer.take()->extractData(), m_contentType);
 }

 String FetchBodyConsumer::takeAsText()
 {
     // FIXME: We could probably text decode on the fly as soon as m_type is set to JSON or Text.
     if (!m_buffer)
         return String();

     auto buffer = m_buffer.takeAsContiguous();
     auto text = TextResourceDecoder::textFromUTF8(buffer->data(), buffer->size());
     return text;
 }

 void FetchBodyConsumer::setConsumePromise(Ref<DeferredPromise>&& promise)
 {
     ASSERT(!m_consumePromise);
     m_userGestureToken = UserGestureIndicator::currentUserGesture();
     m_consumePromise = WTFMove(promise);
 }

 void FetchBodyConsumer::resetConsumePromise()
 {
     m_consumePromise = nullptr;
     m_userGestureToken = nullptr;
 }

 void FetchBodyConsumer::setSource(Ref<FetchBodySource>&& source)
 {
     m_source = WTFMove(source);
     if (m_buffer)
         m_source->enqueue(m_buffer.takeAsArrayBuffer());
 }

 void FetchBodyConsumer::loadingFailed(const Exception& exception)
 {
     m_isLoading = false;
     if (m_consumePromise) {
         m_consumePromise->reject(exception);
         resetConsumePromise();
     }
     if (m_source) {
         m_source->error(exception);
         m_source = nullptr;
     }
 }

 void FetchBodyConsumer::loadingSucceeded(const String& contentType)
 {
     m_isLoading = false;

     if (m_consumePromise) {
         if (!m_userGestureToken || m_userGestureToken->hasExpired(UserGestureToken::maximumIntervalForUserGestureForwardingForFetch()) || !m_userGestureToken->processingUserGesture())
             resolve(m_consumePromise.releaseNonNull(), contentType, nullptr);
         else {
             UserGestureIndicator gestureIndicator(m_userGestureToken, UserGestureToken::GestureScope::MediaOnly, UserGestureToken::IsPropagatedFromFetch::Yes);
             resolve(m_consumePromise.releaseNonNull(), contentType, nullptr);
         }
     }
     if (m_source) {
         m_source->close();
         m_source = nullptr;
     }
 }

 FetchBodyConsumer FetchBodyConsumer::clone()
 {
     FetchBodyConsumer clone { m_type };
     clone.m_contentType = m_contentType;
     clone.m_buffer = m_buffer;
     return clone;
 }

 } // namespace WebCore
	/*
	* Copyright (C) 2016 Apple Inc.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted, provided that the following conditions
	* are required to be met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of Apple Inc. nor the names of
	* its contributors may be used to endorse or promote products derived
	* from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS "AS IS" AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL APPLE INC. AND ITS CONTRIBUTORS BE LIABLE FOR
	* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "FetchBodyConsumer.h"

	#include "DOMFormData.h"
	#include "FormData.h"
	#include "FormDataConsumer.h"
	#include "HTTPHeaderField.h"
	#include "HTTPParsers.h"
	#include "JSBlob.h"
	#include "JSDOMFormData.h"
	#include "TextResourceDecoder.h"
	#include <wtf/StringExtras.h>
	#include <wtf/URLParser.h>

	namespace WebCore {

	static inline Ref<Blob> blobFromData(ScriptExecutionContext* context, Vector<uint8_t>&& data, const String& contentType)
	{
	return Blob::create(context, WTFMove(data), Blob::normalizedContentType(contentType));
	}

	// https://mimesniff.spec.whatwg.org/#http-quoted-string-token-code-point
	static bool isHTTPQuotedStringTokenCodePoint(UChar c)
	{
	return c == 0x09
	\|\| (c >= 0x20 && c <= 0x7E)
	\|\| (c >= 0x80 && c <= 0xFF);
	}

	struct MimeType {
	String type;
	String subtype;
	HashMap<String, String> parameters;
	};

	static HashMap<String, String> parseParameters(StringView input, size_t position)
	{
	HashMap<String, String> parameters;
	while (position < input.length()) {
	while (position < input.length() && RFC7230::isWhitespace(input[position]))
	position++;
	size_t nameBegin = position;
	while (position < input.length() && input[position] != '=' && input[position] != ';')
	position++;
	if (position >= input.length())
	break;
	if (input[position] == ';') {
	position++;
	continue;
	}
	StringView parameterName = input.substring(nameBegin, position - nameBegin);
	position++;
	if (position >= input.length())
	break;

	StringView parameterValue;
	if (position < input.length() && input[position] == '"') {
	position++;
	size_t valueBegin = position;
	while (position < input.length() && input[position] != '"')
	position++;
	parameterValue = input.substring(valueBegin, position - valueBegin);
	position++;
	} else {
	size_t valueBegin = position;
	while (position < input.length() && input[position] != ';')
	position++;
	parameterValue = stripLeadingAndTrailingHTTPSpaces(input.substring(valueBegin, position - valueBegin));
	}

	if (parameterName.length()
	&& isValidHTTPToken(parameterName)
	&& parameterValue.isAllSpecialCharacters<isHTTPQuotedStringTokenCodePoint>()) {
	parameters.ensure(parameterName.toString(), [&] { return parameterValue.toString(); });
	}
	}
	return parameters;
	}

	// https://mimesniff.spec.whatwg.org/#parsing-a-mime-type
	static std::optional<MimeType> parseMIMEType(const String& contentType)
	{
	String input = stripLeadingAndTrailingHTTPSpaces(contentType);
	size_t slashIndex = input.find('/');
	if (slashIndex == notFound)
	return std::nullopt;

	String type = input.left(slashIndex);
	if (!type.length() \|\| !isValidHTTPToken(type))
	return std::nullopt;

	size_t semicolonIndex = input.find(';', slashIndex);
	String subtype = stripLeadingAndTrailingHTTPSpaces(input.substring(slashIndex + 1, semicolonIndex - slashIndex - 1));
	if (!subtype.length() \|\| !isValidHTTPToken(subtype))
	return std::nullopt;

	return {{ WTFMove(type), WTFMove(subtype), parseParameters(StringView(input), semicolonIndex + 1) }};
	}

	// https://fetch.spec.whatwg.org/#concept-body-package-data
	RefPtr<DOMFormData> FetchBodyConsumer::packageFormData(ScriptExecutionContext* context, const String& contentType, const uint8_t* data, size_t length)
	{
	auto parseMultipartPart = [context] (const uint8_t* part, size_t partLength, DOMFormData& form) -> bool {
	const uint8_t* headerEnd = static_cast<const uint8_t*>(memmem(part, partLength, "\r\n\r\n", 4));
	if (!headerEnd)
	return false;
	const uint8_t* headerBegin = part;
	size_t headerLength = headerEnd - headerBegin;

	const uint8_t* bodyBegin = headerEnd + strlen("\r\n\r\n");
	size_t bodyLength = partLength - (bodyBegin - headerBegin);

	String header = String::fromUTF8(headerBegin, headerLength);

	constexpr auto contentDispositionCharacters = "Content-Disposition:"_s;
	size_t contentDispositionBegin = header.find(contentDispositionCharacters);
	if (contentDispositionBegin == notFound)
	return false;
	size_t contentDispositionEnd = header.find("\r\n"_s, contentDispositionBegin);
	size_t contentDispositionParametersBegin = header.find(';', contentDispositionBegin + contentDispositionCharacters.length());
	if (contentDispositionParametersBegin != notFound)
	contentDispositionParametersBegin++;

	auto parameters = parseParameters(StringView(header).substring(contentDispositionParametersBegin, contentDispositionEnd - contentDispositionParametersBegin), 0);
	String name = parameters.get<HashTranslatorASCIILiteral>("name"_s);
	if (!name)
	return false;
	String filename = parameters.get<HashTranslatorASCIILiteral>("filename"_s);
	if (!filename)
	form.append(name, String::fromUTF8(bodyBegin, bodyLength));
	else {
	String contentType = "text/plain"_s;

	constexpr auto contentTypeCharacters = "Content-Type:"_s;
	size_t contentTypePrefixLength = contentTypeCharacters.length();
	size_t contentTypeBegin = header.find(contentTypeCharacters);
	if (contentTypeBegin != notFound) {
	size_t contentTypeEnd = header.find("\r\n"_s, contentTypeBegin);
	contentType = StringView(header).substring(contentTypeBegin + contentTypePrefixLength, contentTypeEnd - contentTypeBegin - contentTypePrefixLength).stripLeadingAndTrailingMatchedCharacters(isHTTPSpace).toString();
	}

	form.append(name, File::create(context, Blob::create(context, Vector { bodyBegin, bodyLength }, Blob::normalizedContentType(contentType)).get(), filename).get(), filename);
	}
	return true;
	};

	auto parseMultipartBoundary = [] (const std::optional<MimeType>& mimeType) -> std::optional<String> {
	if (!mimeType)
	return std::nullopt;
	if (equalLettersIgnoringASCIICase(mimeType->type, "multipart"_s) && equalLettersIgnoringASCIICase(mimeType->subtype, "form-data"_s)) {
	auto iterator = mimeType->parameters.find<HashTranslatorASCIILiteral>("boundary"_s);
	if (iterator != mimeType->parameters.end())
	return iterator->value;
	}
	return std::nullopt;
	};

	auto form = DOMFormData::create(PAL::UTF8Encoding());
	auto mimeType = parseMIMEType(contentType);
	if (auto multipartBoundary = parseMultipartBoundary(mimeType)) {
	auto boundaryWithDashes = makeString("--", *multipartBoundary);
	CString boundary = boundaryWithDashes.utf8();
	size_t boundaryLength = boundary.length();

	const uint8_t* currentBoundary = static_cast<const uint8_t*>(memmem(data, length, boundary.data(), boundaryLength));
	if (!currentBoundary)
	return nullptr;
	const uint8_t* nextBoundary = static_cast<const uint8_t*>(memmem(currentBoundary + boundaryLength, length - (currentBoundary + boundaryLength - data), boundary.data(), boundaryLength));
	if (!nextBoundary)
	return nullptr;
	while (nextBoundary) {
	parseMultipartPart(currentBoundary + boundaryLength, nextBoundary - currentBoundary - boundaryLength - strlen("\r\n"), form.get());
	currentBoundary = nextBoundary;
	nextBoundary = static_cast<const uint8_t*>(memmem(nextBoundary + boundaryLength, length - (nextBoundary + boundaryLength - data), boundary.data(), boundaryLength));
	}
	} else if (mimeType && equalLettersIgnoringASCIICase(mimeType->type, "application"_s) && equalLettersIgnoringASCIICase(mimeType->subtype, "x-www-form-urlencoded"_s)) {
	auto dataString = String::fromUTF8(data, length);
	for (auto& pair : WTF::URLParser::parseURLEncodedForm(dataString))
	form->append(pair.key, pair.value);
	} else
	return nullptr;

	return form;
	}

	static void resolveWithTypeAndData(Ref<DeferredPromise>&& promise, FetchBodyConsumer::Type type, const String& contentType, const unsigned char* data, unsigned length)
	{
	auto* context = promise->scriptExecutionContext();

	switch (type) {
	case FetchBodyConsumer::Type::ArrayBuffer:
	fulfillPromiseWithArrayBuffer(WTFMove(promise), data, length);
	return;
	case FetchBodyConsumer::Type::Blob:
	promise->resolveCallbackValueWithNewlyCreated<IDLInterface<Blob>>([&data, &length, &contentType, context](auto&) {
	return blobFromData(context, { data, length }, contentType);
	});
	return;
	case FetchBodyConsumer::Type::JSON:
	fulfillPromiseWithJSON(WTFMove(promise), TextResourceDecoder::textFromUTF8(data, length));
	return;
	case FetchBodyConsumer::Type::Text:
	promise->resolve<IDLDOMString>(TextResourceDecoder::textFromUTF8(data, length));
	return;
	case FetchBodyConsumer::Type::FormData:
	if (auto formData = FetchBodyConsumer::packageFormData(context, contentType, data, length))
	promise->resolve<IDLInterface<DOMFormData>>(*formData);
	else
	promise->reject(TypeError);
	return;
	case FetchBodyConsumer::Type::None:
	ASSERT_NOT_REACHED();
	return;
	}
	}

	void FetchBodyConsumer::clean()
	{
	m_buffer.reset();
	if (m_formDataConsumer)
	m_formDataConsumer->cancel();
	resetConsumePromise();
	if (m_sink) {
	m_sink->clearCallback();
	return;
	}
	}

	void FetchBodyConsumer::resolveWithData(Ref<DeferredPromise>&& promise, const String& contentType, const unsigned char* data, unsigned length)
	{
	resolveWithTypeAndData(WTFMove(promise), m_type, contentType, data, length);
	}

	void FetchBodyConsumer::resolveWithFormData(Ref<DeferredPromise>&& promise, const String& contentType, const FormData& formData, ScriptExecutionContext* context)
	{
	if (auto sharedBuffer = formData.asSharedBuffer()) {
	resolveWithData(WTFMove(promise), contentType, sharedBuffer->makeContiguous()->data(), sharedBuffer->size());
	return;
	}

	if (!context)
	return;

	m_formDataConsumer = makeUnique<FormDataConsumer>(formData, *context, [this, capturedPromise = WTFMove(promise), contentType, builder = SharedBufferBuilder { }](auto&& result) mutable {
	if (result.hasException()) {
	auto promise = WTFMove(capturedPromise);
	promise->reject(result.releaseException());
	return;
	}

	auto& value = result.returnValue();
	if (value.empty()) {
	auto buffer = builder.takeAsContiguous();
	resolveWithData(WTFMove(capturedPromise), contentType, buffer->data(), buffer->size());
	return;
	}

	builder.append(value);
	});
	}

	void FetchBodyConsumer::consumeFormDataAsStream(const FormData& formData, FetchBodySource& source, ScriptExecutionContext* context)
	{
	if (auto sharedBuffer = formData.asSharedBuffer()) {
	if (source.enqueue(ArrayBuffer::tryCreate(sharedBuffer->makeContiguous()->data(), sharedBuffer->size())))
	source.close();
	return;
	}

	if (!context)
	return;

	m_formDataConsumer = makeUnique<FormDataConsumer>(formData, *context, [this, source = Ref { source }](auto&& result) {
	if (result.hasException()) {
	source->error(result.releaseException());
	return;
	}

	auto& value = result.returnValue();
	if (value.empty()) {
	source->close();
	return;
	}

	if (!source->enqueue(ArrayBuffer::tryCreate(value.data(), value.size())))
	m_formDataConsumer->cancel();
	});
	}

	void FetchBodyConsumer::extract(ReadableStream& stream, ReadableStreamToSharedBufferSink::Callback&& callback)
	{
	ASSERT(!m_sink);
	m_sink = ReadableStreamToSharedBufferSink::create(WTFMove(callback));
	m_sink->pipeFrom(stream);
	}

	void FetchBodyConsumer::resolve(Ref<DeferredPromise>&& promise, const String& contentType, ReadableStream* stream)
	{
	if (stream) {
	ASSERT(!m_sink);
	m_sink = ReadableStreamToSharedBufferSink::create([promise = WTFMove(promise), data = SharedBufferBuilder(), type = m_type, contentType](auto&& result) mutable {
	if (result.hasException()) {
	promise->reject(result.releaseException());
	return;
	}

	if (auto* chunk = result.returnValue())
	data.append(chunk->data(), chunk->size());
	else {
	auto buffer = data.takeAsContiguous();
	resolveWithTypeAndData(WTFMove(promise), type, contentType, buffer->data(), buffer->size());
	}
	});
	m_sink->pipeFrom(*stream);
	return;
	}

	if (m_isLoading) {
	setConsumePromise(WTFMove(promise));
	return;
	}

	auto* context = promise->scriptExecutionContext();

	ASSERT(m_type != Type::None);
	switch (m_type) {
	case Type::ArrayBuffer:
	fulfillPromiseWithArrayBuffer(WTFMove(promise), takeAsArrayBuffer().get());
	return;
	case Type::Blob:
	promise->resolveCallbackValueWithNewlyCreated<IDLInterface<Blob>>([this, context](auto&) {
	return takeAsBlob(context);
	});
	return;
	case Type::JSON:
	fulfillPromiseWithJSON(WTFMove(promise), takeAsText());
	return;
	case Type::Text:
	promise->resolve<IDLDOMString>(takeAsText());
	return;
	case FetchBodyConsumer::Type::FormData: {
	auto buffer = takeData();
	if (auto formData = packageFormData(context, contentType, buffer ? buffer->makeContiguous()->data() : nullptr, buffer ? buffer->size() : 0))
	promise->resolve<IDLInterface<DOMFormData>>(*formData);
	else
	promise->reject(TypeError);
	return;
	}
	case Type::None:
	ASSERT_NOT_REACHED();
	return;
	}
	}

	void FetchBodyConsumer::append(const SharedBuffer& buffer)
	{
	if (m_source) {
	m_source->enqueue(buffer.tryCreateArrayBuffer());
	return;
	}
	m_buffer.append(buffer);
	}

	void FetchBodyConsumer::setData(Ref<FragmentedSharedBuffer>&& data)
	{
	m_buffer = WTFMove(data);
	}

	RefPtr<FragmentedSharedBuffer> FetchBodyConsumer::takeData()
	{
	if (!m_buffer)
	return nullptr;
	return m_buffer.take();
	}

	RefPtr<JSC::ArrayBuffer> FetchBodyConsumer::takeAsArrayBuffer()
	{
	return m_buffer.takeAsArrayBuffer();
	}

	Ref<Blob> FetchBodyConsumer::takeAsBlob(ScriptExecutionContext* context)
	{
	if (!m_buffer)
	return Blob::create(context, Vector<uint8_t>(), Blob::normalizedContentType(m_contentType));

	return blobFromData(context, m_buffer.take()->extractData(), m_contentType);
	}

	String FetchBodyConsumer::takeAsText()
	{
	// FIXME: We could probably text decode on the fly as soon as m_type is set to JSON or Text.
	if (!m_buffer)
	return String();

	auto buffer = m_buffer.takeAsContiguous();
	auto text = TextResourceDecoder::textFromUTF8(buffer->data(), buffer->size());
	return text;
	}

	void FetchBodyConsumer::setConsumePromise(Ref<DeferredPromise>&& promise)
	{
	ASSERT(!m_consumePromise);
	m_userGestureToken = UserGestureIndicator::currentUserGesture();
	m_consumePromise = WTFMove(promise);
	}

	void FetchBodyConsumer::resetConsumePromise()
	{
	m_consumePromise = nullptr;
	m_userGestureToken = nullptr;
	}

	void FetchBodyConsumer::setSource(Ref<FetchBodySource>&& source)
	{
	m_source = WTFMove(source);
	if (m_buffer)
	m_source->enqueue(m_buffer.takeAsArrayBuffer());
	}

	void FetchBodyConsumer::loadingFailed(const Exception& exception)
	{
	m_isLoading = false;
	if (m_consumePromise) {
	m_consumePromise->reject(exception);
	resetConsumePromise();
	}
	if (m_source) {
	m_source->error(exception);
	m_source = nullptr;
	}
	}

	void FetchBodyConsumer::loadingSucceeded(const String& contentType)
	{
	m_isLoading = false;

	if (m_consumePromise) {
	if (!m_userGestureToken \|\| m_userGestureToken->hasExpired(UserGestureToken::maximumIntervalForUserGestureForwardingForFetch()) \|\| !m_userGestureToken->processingUserGesture())
	resolve(m_consumePromise.releaseNonNull(), contentType, nullptr);
	else {
	UserGestureIndicator gestureIndicator(m_userGestureToken, UserGestureToken::GestureScope::MediaOnly, UserGestureToken::IsPropagatedFromFetch::Yes);
	resolve(m_consumePromise.releaseNonNull(), contentType, nullptr);
	}
	}
	if (m_source) {
	m_source->close();
	m_source = nullptr;
	}
	}

	FetchBodyConsumer FetchBodyConsumer::clone()
	{
	FetchBodyConsumer clone { m_type };
	clone.m_contentType = m_contentType;
	clone.m_buffer = m_buffer;
	return clone;
	}

	} // namespace WebCore