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// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * 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.
//     * Neither the name of Google 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT
// OWNER OR 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.

#ifndef PREPARSER_H
#define PREPARSER_H

#include "v8stdint.h"

#ifdef _WIN32

// Setup for Windows DLL export/import. When building the V8 DLL the
// BUILDING_V8_SHARED needs to be defined. When building a program which uses
// the V8 DLL USING_V8_SHARED needs to be defined. When either building the V8
// static library or building a program which uses the V8 static library neither
// BUILDING_V8_SHARED nor USING_V8_SHARED should be defined.
#if defined(BUILDING_V8_SHARED) && defined(USING_V8_SHARED)
#error both BUILDING_V8_SHARED and USING_V8_SHARED are set - please check the\
  build configuration to ensure that at most one of these is set
#endif

#ifdef BUILDING_V8_SHARED
#define V8EXPORT __declspec(dllexport)
#elif USING_V8_SHARED
#define V8EXPORT __declspec(dllimport)
#else
#define V8EXPORT
#endif  // BUILDING_V8_SHARED

#else  // _WIN32

// Setup for Linux shared library export. There is no need to distinguish
// between building or using the V8 shared library, but we should not
// export symbols when we are building a static library.
#if defined(__GNUC__) && (__GNUC__ >= 4) && defined(V8_SHARED)
#define V8EXPORT __attribute__ ((visibility("default")))
#else  // defined(__GNUC__) && (__GNUC__ >= 4)
#define V8EXPORT
#endif  // defined(__GNUC__) && (__GNUC__ >= 4)

#endif  // _WIN32


namespace v8 {


class V8EXPORT PreParserData {
 public:
  PreParserData(size_t size, const uint8_t* data)
      : data_(data), size_(size) { }

  // Create a PreParserData value where stack_overflow reports true.
  static PreParserData StackOverflow() { return PreParserData(0, NULL); }

  // Whether the pre-parser stopped due to a stack overflow.
  // If this is the case, size() and data() should not be used.
  bool stack_overflow() { return size_ == 0u; }

  // The size of the data in bytes.
  size_t size() const { return size_; }

  // Pointer to the data.
  const uint8_t* data() const { return data_; }

 private:
  const uint8_t* const data_;
  const size_t size_;
};


// Interface for a stream of Unicode characters.
class V8EXPORT UnicodeInputStream {  // NOLINT - Thinks V8EXPORT is class name.
 public:
  virtual ~UnicodeInputStream();

  // Returns the next Unicode code-point in the input, or a negative value when
  // there is no more input in the stream.
  virtual int32_t Next() = 0;
};


// Preparse a JavaScript program. The source code is provided as a
// UnicodeInputStream. The max_stack_size limits the amount of stack
// space that the preparser is allowed to use. If the preparser uses
// more stack space than the limit provided, the result's stack_overflow()
// method will return true. Otherwise the result contains preparser
// data that can be used by the V8 parser to speed up parsing.
PreParserData V8EXPORT Preparse(UnicodeInputStream* input,
                                size_t max_stack_size);

}  // namespace v8.

#endif  // PREPARSER_H