source: webkit/trunk/Source/JavaScriptCore/parser/SourceProvider.h

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#pragma once

#include "CachedBytecode.h"
#include "CodeSpecializationKind.h"
#include "SourceOrigin.h"
#include <wtf/RefCounted.h>
#include <wtf/text/TextPosition.h>
#include <wtf/text/WTFString.h>

namespace JSC {

class SourceCode;
class UnlinkedFunctionExecutable;
class UnlinkedFunctionCodeBlock;

enum class SourceProviderSourceType : uint8_t {
Program,
Module,
WebAssembly,
};

using BytecodeCacheGenerator = Function<RefPtr<CachedBytecode>()>;

class SourceProvider : public RefCounted<SourceProvider> {
public:
static const intptr_t nullID = 1;

JS_EXPORT_PRIVATE SourceProvider(const SourceOrigin&, String&& sourceURL, const TextPosition& startPosition, SourceProviderSourceType);

JS_EXPORT_PRIVATE virtual ~SourceProvider();

virtual unsigned hash() const = 0;
virtual StringView source() const = 0;
virtual RefPtr<CachedBytecode> cachedBytecode() const { return nullptr; }
virtual void cacheBytecode(const BytecodeCacheGenerator&) const { }
virtual void updateCache(const UnlinkedFunctionExecutable*, const SourceCode&, CodeSpecializationKind, const UnlinkedFunctionCodeBlock*) const { }
virtual void commitCachedBytecode() const { }

StringView getRange(int start, int end) const
{
return source().substring(start, end - start);
}

const SourceOrigin& sourceOrigin() const { return m_sourceOrigin; }

// This is NOT the path that should be used for computing relative paths from a script. Use SourceOrigin's URL for that, the values may or may not be the same...
const String& sourceURL() const { return m_sourceURL; }
const String& sourceURLDirective() const { return m_sourceURLDirective; }
const String& sourceMappingURLDirective() const { return m_sourceMappingURLDirective; }

TextPosition startPosition() const { return m_startPosition; }
SourceProviderSourceType sourceType() const { return m_sourceType; }

SourceID asID()
{
if (!m_id)
getID();
return m_id;
}

void setSourceURLDirective(const String& sourceURLDirective) { m_sourceURLDirective = sourceURLDirective; }
void setSourceMappingURLDirective(const String& sourceMappingURLDirective) { m_sourceMappingURLDirective = sourceMappingURLDirective; }

private:
JS_EXPORT_PRIVATE void getID();

SourceProviderSourceType m_sourceType;
SourceOrigin m_sourceOrigin;
String m_sourceURL;
String m_sourceURLDirective;
String m_sourceMappingURLDirective;
TextPosition m_startPosition;
SourceID m_id { 0 };
};

DECLARE_ALLOCATOR_WITH_HEAP_IDENTIFIER(StringSourceProvider);
class StringSourceProvider : public SourceProvider {
WTF_MAKE_FAST_ALLOCATED_WITH_HEAP_IDENTIFIER(StringSourceProvider);
public:
static Ref<StringSourceProvider> create(const String& source, const SourceOrigin& sourceOrigin, String sourceURL, const TextPosition& startPosition = TextPosition(), SourceProviderSourceType sourceType = SourceProviderSourceType::Program)
{
return adoptRef(*new StringSourceProvider(source, sourceOrigin, WTFMove(sourceURL), startPosition, sourceType));
}

unsigned hash() const override
{
return m_source.get().hash();
}

StringView source() const override
{
return m_source.get();
}

protected:
StringSourceProvider(const String& source, const SourceOrigin& sourceOrigin, String&& sourceURL, const TextPosition& startPosition, SourceProviderSourceType sourceType)
: SourceProvider(sourceOrigin, WTFMove(sourceURL), startPosition, sourceType)
, m_source(source.isNull() ? *StringImpl::empty() : *source.impl())
{
}

private:
Ref<StringImpl> m_source;
};

#if ENABLE(WEBASSEMBLY)
class BaseWebAssemblySourceProvider : public SourceProvider {
public:
virtual const uint8_t* data() = 0;
virtual size_t size() const = 0;
virtual void lockUnderlyingBuffer() { }
virtual void unlockUnderlyingBuffer() { }

protected:
JS_EXPORT_PRIVATE BaseWebAssemblySourceProvider(const SourceOrigin&, String&&);
};

class WebAssemblySourceProvider final : public BaseWebAssemblySourceProvider {
public:
static Ref<WebAssemblySourceProvider> create(Vector<uint8_t>&& data, const SourceOrigin& sourceOrigin, String sourceURL)
{
return adoptRef(*new WebAssemblySourceProvider(WTFMove(data), sourceOrigin, WTFMove(sourceURL)));
}

unsigned hash() const final
{
return m_source.impl()->hash();
}

StringView source() const final
{
return m_source;
}

const uint8_t* data() final
{
return m_data.data();
}

size_t size() const final
{
return m_data.size();
}

const Vector<uint8_t>& dataVector() const
{
return m_data;
}

private:
WebAssemblySourceProvider(Vector<uint8_t>&& data, const SourceOrigin& sourceOrigin, String&& sourceURL)
: BaseWebAssemblySourceProvider(sourceOrigin, WTFMove(sourceURL))
, m_source("[WebAssembly source]"_s)
, m_data(WTFMove(data))
{
}

String m_source;
Vector<uint8_t> m_data;
};

// RAII class for managing a Wasm source provider's underlying buffer.
class WebAssemblySourceProviderBufferGuard {
public:
explicit WebAssemblySourceProviderBufferGuard(BaseWebAssemblySourceProvider* sourceProvider)
: m_sourceProvider(sourceProvider)
{
if (m_sourceProvider)
m_sourceProvider->lockUnderlyingBuffer();
}

~WebAssemblySourceProviderBufferGuard()
{
if (m_sourceProvider)
m_sourceProvider->unlockUnderlyingBuffer();
}

private:
RefPtr<BaseWebAssemblySourceProvider> m_sourceProvider;
};
#endif

} // namespace JSC