root/src/d8.cc

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DEFINITIONS

This source file includes following definitions.
  1. next_
  2. Get
  3. Prompt
  4. Match
  5. ToCString
  6. ExecuteString
  7. Print
  8. Write
  9. EnableProfiler
  10. DisableProfiler
  11. Read
  12. ReadFromStdin
  13. Load
  14. convertToInt
  15. convertToUint
  16. CreateExternalArrayBuffer
  17. ArrayBuffer
  18. CreateExternalArray
  19. CreateExternalArray
  20. ArrayBufferSlice
  21. ArraySubArray
  22. ArraySet
  23. ExternalArrayWeakCallback
  24. Int8Array
  25. Uint8Array
  26. Int16Array
  27. Uint16Array
  28. Int32Array
  29. Uint32Array
  30. Float32Array
  31. Float64Array
  32. Uint8ClampedArray
  33. Yield
  34. Quit
  35. Version
  36. ReportException
  37. GetCompletions
  38. DebugMessageDetails
  39. DebugCommandToJSONRequest
  40. DispatchDebugMessages
  41. Bind
  42. AddSample
  43. GetNextCounter
  44. MapCounters
  45. Hash
  46. GetCounter
  47. LookupCounter
  48. CreateHistogram
  49. AddHistogramSample
  50. InstallUtilityScript
  51. DecompressData
  52. CreateArrayBufferTemplate
  53. CreateArrayTemplate
  54. CreateGlobalTemplate
  55. Initialize
  56. CreateEvaluationContext
  57. Exit
  58. CompareKeys
  59. OnExit
  60. FOpen
  61. ReadChars
  62. ReadBuffer
  63. ReadToken
  64. ReadLine
  65. ReadWord
  66. ReadFile
  67. RunShell
  68. files_
  69. Run
  70. Execute
  71. ReadFile
  72. GetThreadOptions
  73. ExecuteInThread
  74. StartExecuteInThread
  75. WaitForThread
  76. SetOptions
  77. RunMain
  78. Main
  79. main

// Copyright 2012 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.


// Defined when linking against shared lib on Windows.
#if defined(USING_V8_SHARED) && !defined(V8_SHARED)
#define V8_SHARED
#endif

#ifdef COMPRESS_STARTUP_DATA_BZ2
#include <bzlib.h>
#endif

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

#ifdef V8_SHARED
#include <assert.h>
#include "../include/v8-testing.h"
#endif  // V8_SHARED

#include "d8.h"

#ifndef V8_SHARED
#include "api.h"
#include "checks.h"
#include "d8-debug.h"
#include "debug.h"
#include "natives.h"
#include "platform.h"
#include "v8.h"
#endif  // V8_SHARED

#if !defined(_WIN32) && !defined(_WIN64)
#include <unistd.h>  // NOLINT
#endif

#ifndef ASSERT
#define ASSERT(condition) assert(condition)
#endif

namespace v8 {

LineEditor *LineEditor::first_ = NULL;


LineEditor::LineEditor(Type type, const char* name)
    : type_(type),
      name_(name),
      next_(first_) {
  first_ = this;
}


LineEditor* LineEditor::Get() {
  LineEditor* current = first_;
  LineEditor* best = current;
  while (current != NULL) {
    if (current->type_ > best->type_)
      best = current;
    current = current->next_;
  }
  return best;
}


class DumbLineEditor: public LineEditor {
 public:
  DumbLineEditor() : LineEditor(LineEditor::DUMB, "dumb") { }
  virtual Handle<String> Prompt(const char* prompt);
};


static DumbLineEditor dumb_line_editor;


Handle<String> DumbLineEditor::Prompt(const char* prompt) {
  printf("%s", prompt);
  return Shell::ReadFromStdin();
}


#ifndef V8_SHARED
CounterMap* Shell::counter_map_;
i::OS::MemoryMappedFile* Shell::counters_file_ = NULL;
CounterCollection Shell::local_counters_;
CounterCollection* Shell::counters_ = &local_counters_;
i::Mutex* Shell::context_mutex_(i::OS::CreateMutex());
Persistent<Context> Shell::utility_context_;
#endif  // V8_SHARED

LineEditor* Shell::console = NULL;
Persistent<Context> Shell::evaluation_context_;
ShellOptions Shell::options;
const char* Shell::kPrompt = "d8> ";


const int MB = 1024 * 1024;


#ifndef V8_SHARED
bool CounterMap::Match(void* key1, void* key2) {
  const char* name1 = reinterpret_cast<const char*>(key1);
  const char* name2 = reinterpret_cast<const char*>(key2);
  return strcmp(name1, name2) == 0;
}
#endif  // V8_SHARED


// Converts a V8 value to a C string.
const char* Shell::ToCString(const v8::String::Utf8Value& value) {
  return *value ? *value : "<string conversion failed>";
}


// Executes a string within the current v8 context.
bool Shell::ExecuteString(Handle<String> source,
                          Handle<Value> name,
                          bool print_result,
                          bool report_exceptions) {
#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
  bool FLAG_debugger = i::FLAG_debugger;
#else
  bool FLAG_debugger = false;
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT
  HandleScope handle_scope;
  TryCatch try_catch;
  options.script_executed = true;
  if (FLAG_debugger) {
    // When debugging make exceptions appear to be uncaught.
    try_catch.SetVerbose(true);
  }
  Handle<Script> script = Script::Compile(source, name);
  if (script.IsEmpty()) {
    // Print errors that happened during compilation.
    if (report_exceptions && !FLAG_debugger)
      ReportException(&try_catch);
    return false;
  } else {
    Handle<Value> result = script->Run();
    if (result.IsEmpty()) {
      ASSERT(try_catch.HasCaught());
      // Print errors that happened during execution.
      if (report_exceptions && !FLAG_debugger)
        ReportException(&try_catch);
      return false;
    } else {
      ASSERT(!try_catch.HasCaught());
      if (print_result && !result->IsUndefined()) {
        // If all went well and the result wasn't undefined then print
        // the returned value.
        v8::String::Utf8Value str(result);
        size_t count = fwrite(*str, sizeof(**str), str.length(), stdout);
        (void) count;  // Silence GCC-4.5.x "unused result" warning.
        printf("\n");
      }
      return true;
    }
  }
}


Handle<Value> Shell::Print(const Arguments& args) {
  Handle<Value> val = Write(args);
  printf("\n");
  fflush(stdout);
  return val;
}


Handle<Value> Shell::Write(const Arguments& args) {
  for (int i = 0; i < args.Length(); i++) {
    HandleScope handle_scope;
    if (i != 0) {
      printf(" ");
    }
    v8::String::Utf8Value str(args[i]);
    int n = static_cast<int>(fwrite(*str, sizeof(**str), str.length(), stdout));
    if (n != str.length()) {
      printf("Error in fwrite\n");
      Exit(1);
    }
  }
  return Undefined();
}


Handle<Value> Shell::EnableProfiler(const Arguments& args) {
  V8::ResumeProfiler();
  return Undefined();
}


Handle<Value> Shell::DisableProfiler(const Arguments& args) {
  V8::PauseProfiler();
  return Undefined();
}


Handle<Value> Shell::Read(const Arguments& args) {
  String::Utf8Value file(args[0]);
  if (*file == NULL) {
    return ThrowException(String::New("Error loading file"));
  }
  Handle<String> source = ReadFile(*file);
  if (source.IsEmpty()) {
    return ThrowException(String::New("Error loading file"));
  }
  return source;
}


Handle<String> Shell::ReadFromStdin() {
  static const int kBufferSize = 256;
  char buffer[kBufferSize];
  Handle<String> accumulator = String::New("");
  int length;
  while (true) {
    // Continue reading if the line ends with an escape '\\' or the line has
    // not been fully read into the buffer yet (does not end with '\n').
    // If fgets gets an error, just give up.
    char* input = NULL;
    {  // Release lock for blocking input.
      Unlocker unlock(Isolate::GetCurrent());
      input = fgets(buffer, kBufferSize, stdin);
    }
    if (input == NULL) return Handle<String>();
    length = static_cast<int>(strlen(buffer));
    if (length == 0) {
      return accumulator;
    } else if (buffer[length-1] != '\n') {
      accumulator = String::Concat(accumulator, String::New(buffer, length));
    } else if (length > 1 && buffer[length-2] == '\\') {
      buffer[length-2] = '\n';
      accumulator = String::Concat(accumulator, String::New(buffer, length-1));
    } else {
      return String::Concat(accumulator, String::New(buffer, length-1));
    }
  }
}


Handle<Value> Shell::Load(const Arguments& args) {
  for (int i = 0; i < args.Length(); i++) {
    HandleScope handle_scope;
    String::Utf8Value file(args[i]);
    if (*file == NULL) {
      return ThrowException(String::New("Error loading file"));
    }
    Handle<String> source = ReadFile(*file);
    if (source.IsEmpty()) {
      return ThrowException(String::New("Error loading file"));
    }
    if (!ExecuteString(source, String::New(*file), false, true)) {
      return ThrowException(String::New("Error executing file"));
    }
  }
  return Undefined();
}

static int32_t convertToInt(Local<Value> value_in, TryCatch* try_catch) {
  if (value_in->IsInt32()) {
    return value_in->Int32Value();
  }

  Local<Value> number = value_in->ToNumber();
  if (try_catch->HasCaught()) return 0;

  ASSERT(number->IsNumber());
  Local<Int32> int32 = number->ToInt32();
  if (try_catch->HasCaught() || int32.IsEmpty()) return 0;

  int32_t value = int32->Int32Value();
  if (try_catch->HasCaught()) return 0;

  return value;
}


static int32_t convertToUint(Local<Value> value_in, TryCatch* try_catch) {
  int32_t raw_value = convertToInt(value_in, try_catch);
  if (try_catch->HasCaught()) return 0;

  if (raw_value < 0) {
    ThrowException(String::New("Array length must not be negative."));
    return 0;
  }

  static const int kMaxLength = 0x3fffffff;
#ifndef V8_SHARED
  ASSERT(kMaxLength == i::ExternalArray::kMaxLength);
#endif  // V8_SHARED
  if (raw_value > static_cast<int32_t>(kMaxLength)) {
    ThrowException(
        String::New("Array length exceeds maximum length."));
  }
  return raw_value;
}


// TODO(rossberg): should replace these by proper uses of HasInstance,
// once we figure out a good way to make the templates global.
const char kArrayBufferMarkerPropName[] = "d8::_is_array_buffer_";
const char kArrayMarkerPropName[] = "d8::_is_typed_array_";


Handle<Value> Shell::CreateExternalArrayBuffer(Handle<Object> buffer,
                                               int32_t length) {
  static const int32_t kMaxSize = 0x7fffffff;
  // Make sure the total size fits into a (signed) int.
  if (length < 0 || length > kMaxSize) {
    return ThrowException(String::New("ArrayBuffer exceeds maximum size (2G)"));
  }
  uint8_t* data = new uint8_t[length];
  if (data == NULL) {
    return ThrowException(String::New("Memory allocation failed"));
  }
  memset(data, 0, length);

  buffer->SetHiddenValue(String::New(kArrayBufferMarkerPropName), True());
  Persistent<Object> persistent_array = Persistent<Object>::New(buffer);
  persistent_array.MakeWeak(data, ExternalArrayWeakCallback);
  persistent_array.MarkIndependent();
  V8::AdjustAmountOfExternalAllocatedMemory(length);

  buffer->SetIndexedPropertiesToExternalArrayData(
      data, v8::kExternalByteArray, length);
  buffer->Set(String::New("byteLength"), Int32::New(length), ReadOnly);

  return buffer;
}


Handle<Value> Shell::ArrayBuffer(const Arguments& args) {
  if (!args.IsConstructCall()) {
    Handle<Value>* rec_args = new Handle<Value>[args.Length()];
    for (int i = 0; i < args.Length(); ++i) rec_args[i] = args[i];
    Handle<Value> result = args.Callee()->NewInstance(args.Length(), rec_args);
    delete[] rec_args;
    return result;
  }

  if (args.Length() == 0) {
    return ThrowException(
        String::New("ArrayBuffer constructor must have one argument"));
  }
  TryCatch try_catch;
  int32_t length = convertToUint(args[0], &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();

  return CreateExternalArrayBuffer(args.This(), length);
}


Handle<Object> Shell::CreateExternalArray(Handle<Object> array,
                                          Handle<Object> buffer,
                                          ExternalArrayType type,
                                          int32_t length,
                                          int32_t byteLength,
                                          int32_t byteOffset,
                                          int32_t element_size) {
  ASSERT(element_size == 1 || element_size == 2 ||
         element_size == 4 || element_size == 8);
  ASSERT(byteLength == length * element_size);

  void* data = buffer->GetIndexedPropertiesExternalArrayData();
  ASSERT(data != NULL);

  array->SetIndexedPropertiesToExternalArrayData(
      static_cast<uint8_t*>(data) + byteOffset, type, length);
  array->SetHiddenValue(String::New(kArrayMarkerPropName), Int32::New(type));
  array->Set(String::New("byteLength"), Int32::New(byteLength), ReadOnly);
  array->Set(String::New("byteOffset"), Int32::New(byteOffset), ReadOnly);
  array->Set(String::New("length"), Int32::New(length), ReadOnly);
  array->Set(String::New("BYTES_PER_ELEMENT"), Int32::New(element_size));
  array->Set(String::New("buffer"), buffer, ReadOnly);

  return array;
}


Handle<Value> Shell::CreateExternalArray(const Arguments& args,
                                         ExternalArrayType type,
                                         int32_t element_size) {
  if (!args.IsConstructCall()) {
    Handle<Value>* rec_args = new Handle<Value>[args.Length()];
    for (int i = 0; i < args.Length(); ++i) rec_args[i] = args[i];
    Handle<Value> result = args.Callee()->NewInstance(args.Length(), rec_args);
    delete[] rec_args;
    return result;
  }

  TryCatch try_catch;
  ASSERT(element_size == 1 || element_size == 2 ||
         element_size == 4 || element_size == 8);

  // All of the following constructors are supported:
  //   TypedArray(unsigned long length)
  //   TypedArray(type[] array)
  //   TypedArray(TypedArray array)
  //   TypedArray(ArrayBuffer buffer,
  //              optional unsigned long byteOffset,
  //              optional unsigned long length)
  Handle<Object> buffer;
  int32_t length;
  int32_t byteLength;
  int32_t byteOffset;
  bool init_from_array = false;
  if (args.Length() == 0) {
    return ThrowException(
        String::New("Array constructor must have at least one argument"));
  }
  if (args[0]->IsObject() &&
      !args[0]->ToObject()->GetHiddenValue(
          String::New(kArrayBufferMarkerPropName)).IsEmpty()) {
    // Construct from ArrayBuffer.
    buffer = args[0]->ToObject();
    int32_t bufferLength =
        convertToUint(buffer->Get(String::New("byteLength")), &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();

    if (args.Length() < 2 || args[1]->IsUndefined()) {
      byteOffset = 0;
    } else {
      byteOffset = convertToUint(args[1], &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();
      if (byteOffset > bufferLength) {
        return ThrowException(String::New("byteOffset out of bounds"));
      }
      if (byteOffset % element_size != 0) {
        return ThrowException(
            String::New("byteOffset must be multiple of element size"));
      }
    }

    if (args.Length() < 3 || args[2]->IsUndefined()) {
      byteLength = bufferLength - byteOffset;
      length = byteLength / element_size;
      if (byteLength % element_size != 0) {
        return ThrowException(
            String::New("buffer size must be multiple of element size"));
      }
    } else {
      length = convertToUint(args[2], &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();
      byteLength = length * element_size;
      if (byteOffset + byteLength > bufferLength) {
        return ThrowException(String::New("length out of bounds"));
      }
    }
  } else {
    if (args[0]->IsObject() &&
        args[0]->ToObject()->Has(String::New("length"))) {
      // Construct from array.
      length = convertToUint(
          args[0]->ToObject()->Get(String::New("length")), &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();
      init_from_array = true;
    } else {
      // Construct from size.
      length = convertToUint(args[0], &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();
    }
    byteLength = length * element_size;
    byteOffset = 0;

    Handle<Object> global = Context::GetCurrent()->Global();
    Handle<Value> array_buffer = global->Get(String::New("ArrayBuffer"));
    ASSERT(!try_catch.HasCaught() && array_buffer->IsFunction());
    Handle<Value> buffer_args[] = { Uint32::New(byteLength) };
    Handle<Value> result = Handle<Function>::Cast(array_buffer)->NewInstance(
        1, buffer_args);
    if (try_catch.HasCaught()) return result;
    buffer = result->ToObject();
  }

  Handle<Object> array = CreateExternalArray(
      args.This(), buffer, type, length, byteLength, byteOffset, element_size);

  if (init_from_array) {
    Handle<Object> init = args[0]->ToObject();
    for (int i = 0; i < length; ++i) array->Set(i, init->Get(i));
  }

  return array;
}


Handle<Value> Shell::ArrayBufferSlice(const Arguments& args) {
  TryCatch try_catch;

  if (!args.This()->IsObject()) {
    return ThrowException(
        String::New("'slice' invoked on non-object receiver"));
  }

  Local<Object> self = args.This();
  Local<Value> marker =
      self->GetHiddenValue(String::New(kArrayBufferMarkerPropName));
  if (marker.IsEmpty()) {
    return ThrowException(
        String::New("'slice' invoked on wrong receiver type"));
  }

  int32_t length =
      convertToUint(self->Get(String::New("byteLength")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();

  if (args.Length() == 0) {
    return ThrowException(
        String::New("'slice' must have at least one argument"));
  }
  int32_t begin = convertToInt(args[0], &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  if (begin < 0) begin += length;
  if (begin < 0) begin = 0;
  if (begin > length) begin = length;

  int32_t end;
  if (args.Length() < 2 || args[1]->IsUndefined()) {
    end = length;
  } else {
    end = convertToInt(args[1], &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    if (end < 0) end += length;
    if (end < 0) end = 0;
    if (end > length) end = length;
    if (end < begin) end = begin;
  }

  Local<Function> constructor = Local<Function>::Cast(self->GetConstructor());
  Handle<Value> new_args[] = { Uint32::New(end - begin) };
  Handle<Value> result = constructor->NewInstance(1, new_args);
  if (try_catch.HasCaught()) return result;
  Handle<Object> buffer = result->ToObject();
  uint8_t* dest =
      static_cast<uint8_t*>(buffer->GetIndexedPropertiesExternalArrayData());
  uint8_t* src = begin + static_cast<uint8_t*>(
      self->GetIndexedPropertiesExternalArrayData());
  memcpy(dest, src, end - begin);

  return buffer;
}


Handle<Value> Shell::ArraySubArray(const Arguments& args) {
  TryCatch try_catch;

  if (!args.This()->IsObject()) {
    return ThrowException(
        String::New("'subarray' invoked on non-object receiver"));
  }

  Local<Object> self = args.This();
  Local<Value> marker = self->GetHiddenValue(String::New(kArrayMarkerPropName));
  if (marker.IsEmpty()) {
    return ThrowException(
        String::New("'subarray' invoked on wrong receiver type"));
  }

  Handle<Object> buffer = self->Get(String::New("buffer"))->ToObject();
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  int32_t length =
      convertToUint(self->Get(String::New("length")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  int32_t byteOffset =
      convertToUint(self->Get(String::New("byteOffset")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  int32_t element_size =
      convertToUint(self->Get(String::New("BYTES_PER_ELEMENT")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();

  if (args.Length() == 0) {
    return ThrowException(
        String::New("'subarray' must have at least one argument"));
  }
  int32_t begin = convertToInt(args[0], &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  if (begin < 0) begin += length;
  if (begin < 0) begin = 0;
  if (begin > length) begin = length;

  int32_t end;
  if (args.Length() < 2 || args[1]->IsUndefined()) {
    end = length;
  } else {
    end = convertToInt(args[1], &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    if (end < 0) end += length;
    if (end < 0) end = 0;
    if (end > length) end = length;
    if (end < begin) end = begin;
  }

  length = end - begin;
  byteOffset += begin * element_size;

  Local<Function> constructor = Local<Function>::Cast(self->GetConstructor());
  Handle<Value> construct_args[] = {
    buffer, Uint32::New(byteOffset), Uint32::New(length)
  };
  return constructor->NewInstance(3, construct_args);
}


Handle<Value> Shell::ArraySet(const Arguments& args) {
  TryCatch try_catch;

  if (!args.This()->IsObject()) {
    return ThrowException(
        String::New("'set' invoked on non-object receiver"));
  }

  Local<Object> self = args.This();
  Local<Value> marker = self->GetHiddenValue(String::New(kArrayMarkerPropName));
  if (marker.IsEmpty()) {
    return ThrowException(
        String::New("'set' invoked on wrong receiver type"));
  }
  int32_t length =
      convertToUint(self->Get(String::New("length")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();
  int32_t element_size =
      convertToUint(self->Get(String::New("BYTES_PER_ELEMENT")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();

  if (args.Length() == 0) {
    return ThrowException(
        String::New("'set' must have at least one argument"));
  }
  if (!args[0]->IsObject() ||
      !args[0]->ToObject()->Has(String::New("length"))) {
    return ThrowException(
        String::New("'set' invoked with non-array argument"));
  }
  Handle<Object> source = args[0]->ToObject();
  int32_t source_length =
      convertToUint(source->Get(String::New("length")), &try_catch);
  if (try_catch.HasCaught()) return try_catch.ReThrow();

  int32_t offset;
  if (args.Length() < 2 || args[1]->IsUndefined()) {
    offset = 0;
  } else {
    offset = convertToUint(args[1], &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();
  }
  if (offset + source_length > length) {
    return ThrowException(String::New("offset or source length out of bounds"));
  }

  int32_t source_element_size;
  if (source->GetHiddenValue(String::New(kArrayMarkerPropName)).IsEmpty()) {
    source_element_size = 0;
  } else {
    source_element_size =
       convertToUint(source->Get(String::New("BYTES_PER_ELEMENT")), &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();
  }

  if (element_size == source_element_size &&
      self->GetConstructor()->StrictEquals(source->GetConstructor())) {
    // Use memmove on the array buffers.
    Handle<Object> buffer = self->Get(String::New("buffer"))->ToObject();
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    Handle<Object> source_buffer =
        source->Get(String::New("buffer"))->ToObject();
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    int32_t byteOffset =
        convertToUint(self->Get(String::New("byteOffset")), &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    int32_t source_byteOffset =
        convertToUint(source->Get(String::New("byteOffset")), &try_catch);
    if (try_catch.HasCaught()) return try_catch.ReThrow();

    uint8_t* dest = byteOffset + offset * element_size + static_cast<uint8_t*>(
        buffer->GetIndexedPropertiesExternalArrayData());
    uint8_t* src = source_byteOffset + static_cast<uint8_t*>(
        source_buffer->GetIndexedPropertiesExternalArrayData());
    memmove(dest, src, source_length * element_size);
  } else if (source_element_size == 0) {
    // Source is not a typed array, copy element-wise sequentially.
    for (int i = 0; i < source_length; ++i) {
      self->Set(offset + i, source->Get(i));
      if (try_catch.HasCaught()) return try_catch.ReThrow();
    }
  } else {
    // Need to copy element-wise to make the right conversions.
    Handle<Object> buffer = self->Get(String::New("buffer"))->ToObject();
    if (try_catch.HasCaught()) return try_catch.ReThrow();
    Handle<Object> source_buffer =
        source->Get(String::New("buffer"))->ToObject();
    if (try_catch.HasCaught()) return try_catch.ReThrow();

    if (buffer->StrictEquals(source_buffer)) {
      // Same backing store, need to handle overlap correctly.
      // This gets a bit tricky in the case of different element sizes
      // (which, of course, is extremely unlikely to ever occur in practice).
      int32_t byteOffset =
          convertToUint(self->Get(String::New("byteOffset")), &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();
      int32_t source_byteOffset =
          convertToUint(source->Get(String::New("byteOffset")), &try_catch);
      if (try_catch.HasCaught()) return try_catch.ReThrow();

      // Copy as much as we can from left to right.
      int i = 0;
      int32_t next_dest_offset = byteOffset + (offset + 1) * element_size;
      int32_t next_src_offset = source_byteOffset + source_element_size;
      while (i < length && next_dest_offset <= next_src_offset) {
        self->Set(offset + i, source->Get(i));
        ++i;
        next_dest_offset += element_size;
        next_src_offset += source_element_size;
      }
      // Of what's left, copy as much as we can from right to left.
      int j = length - 1;
      int32_t dest_offset = byteOffset + (offset + j) * element_size;
      int32_t src_offset = source_byteOffset + j * source_element_size;
      while (j >= i && dest_offset >= src_offset) {
        self->Set(offset + j, source->Get(j));
        --j;
        dest_offset -= element_size;
        src_offset -= source_element_size;
      }
      // There can be at most 8 entries left in the middle that need buffering
      // (because the largest element_size is 8 times the smallest).
      ASSERT(j+1 - i <= 8);
      Handle<Value> temp[8];
      for (int k = i; k <= j; ++k) {
        temp[k - i] = source->Get(k);
      }
      for (int k = i; k <= j; ++k) {
        self->Set(offset + k, temp[k - i]);
      }
    } else {
      // Different backing stores, safe to copy element-wise sequentially.
      for (int i = 0; i < source_length; ++i)
        self->Set(offset + i, source->Get(i));
    }
  }

  return Undefined();
}


void Shell::ExternalArrayWeakCallback(Persistent<Value> object, void* data) {
  HandleScope scope;
  int32_t length =
      object->ToObject()->Get(String::New("byteLength"))->Uint32Value();
  V8::AdjustAmountOfExternalAllocatedMemory(-length);
  delete[] static_cast<uint8_t*>(data);
  object.Dispose();
}


Handle<Value> Shell::Int8Array(const Arguments& args) {
  return CreateExternalArray(args, v8::kExternalByteArray, sizeof(int8_t));
}


Handle<Value> Shell::Uint8Array(const Arguments& args) {
  return CreateExternalArray(args, kExternalUnsignedByteArray, sizeof(uint8_t));
}


Handle<Value> Shell::Int16Array(const Arguments& args) {
  return CreateExternalArray(args, kExternalShortArray, sizeof(int16_t));
}


Handle<Value> Shell::Uint16Array(const Arguments& args) {
  return CreateExternalArray(
      args, kExternalUnsignedShortArray, sizeof(uint16_t));
}


Handle<Value> Shell::Int32Array(const Arguments& args) {
  return CreateExternalArray(args, kExternalIntArray, sizeof(int32_t));
}


Handle<Value> Shell::Uint32Array(const Arguments& args) {
  return CreateExternalArray(args, kExternalUnsignedIntArray, sizeof(uint32_t));
}


Handle<Value> Shell::Float32Array(const Arguments& args) {
  return CreateExternalArray(
      args, kExternalFloatArray, sizeof(float));  // NOLINT
}


Handle<Value> Shell::Float64Array(const Arguments& args) {
  return CreateExternalArray(
      args, kExternalDoubleArray, sizeof(double));  // NOLINT
}


Handle<Value> Shell::Uint8ClampedArray(const Arguments& args) {
  return CreateExternalArray(args, kExternalPixelArray, sizeof(uint8_t));
}


Handle<Value> Shell::Yield(const Arguments& args) {
  v8::Unlocker unlocker;
  return Undefined();
}


Handle<Value> Shell::Quit(const Arguments& args) {
  int exit_code = args[0]->Int32Value();
#ifndef V8_SHARED
  OnExit();
#endif  // V8_SHARED
  exit(exit_code);
  return Undefined();
}


Handle<Value> Shell::Version(const Arguments& args) {
  return String::New(V8::GetVersion());
}


void Shell::ReportException(v8::TryCatch* try_catch) {
  HandleScope handle_scope;
#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
  bool enter_context = !Context::InContext();
  if (enter_context) utility_context_->Enter();
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT
  v8::String::Utf8Value exception(try_catch->Exception());
  const char* exception_string = ToCString(exception);
  Handle<Message> message = try_catch->Message();
  if (message.IsEmpty()) {
    // V8 didn't provide any extra information about this error; just
    // print the exception.
    printf("%s\n", exception_string);
  } else {
    // Print (filename):(line number): (message).
    v8::String::Utf8Value filename(message->GetScriptResourceName());
    const char* filename_string = ToCString(filename);
    int linenum = message->GetLineNumber();
    printf("%s:%i: %s\n", filename_string, linenum, exception_string);
    // Print line of source code.
    v8::String::Utf8Value sourceline(message->GetSourceLine());
    const char* sourceline_string = ToCString(sourceline);
    printf("%s\n", sourceline_string);
    // Print wavy underline (GetUnderline is deprecated).
    int start = message->GetStartColumn();
    for (int i = 0; i < start; i++) {
      printf(" ");
    }
    int end = message->GetEndColumn();
    for (int i = start; i < end; i++) {
      printf("^");
    }
    printf("\n");
    v8::String::Utf8Value stack_trace(try_catch->StackTrace());
    if (stack_trace.length() > 0) {
      const char* stack_trace_string = ToCString(stack_trace);
      printf("%s\n", stack_trace_string);
    }
  }
  printf("\n");
#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
  if (enter_context) utility_context_->Exit();
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT
}


#ifndef V8_SHARED
Handle<Array> Shell::GetCompletions(Handle<String> text, Handle<String> full) {
  HandleScope handle_scope;
  Context::Scope context_scope(utility_context_);
  Handle<Object> global = utility_context_->Global();
  Handle<Value> fun = global->Get(String::New("GetCompletions"));
  static const int kArgc = 3;
  Handle<Value> argv[kArgc] = { evaluation_context_->Global(), text, full };
  Handle<Value> val = Handle<Function>::Cast(fun)->Call(global, kArgc, argv);
  return handle_scope.Close(Handle<Array>::Cast(val));
}


#ifdef ENABLE_DEBUGGER_SUPPORT
Handle<Object> Shell::DebugMessageDetails(Handle<String> message) {
  Context::Scope context_scope(utility_context_);
  Handle<Object> global = utility_context_->Global();
  Handle<Value> fun = global->Get(String::New("DebugMessageDetails"));
  static const int kArgc = 1;
  Handle<Value> argv[kArgc] = { message };
  Handle<Value> val = Handle<Function>::Cast(fun)->Call(global, kArgc, argv);
  return Handle<Object>::Cast(val);
}


Handle<Value> Shell::DebugCommandToJSONRequest(Handle<String> command) {
  Context::Scope context_scope(utility_context_);
  Handle<Object> global = utility_context_->Global();
  Handle<Value> fun = global->Get(String::New("DebugCommandToJSONRequest"));
  static const int kArgc = 1;
  Handle<Value> argv[kArgc] = { command };
  Handle<Value> val = Handle<Function>::Cast(fun)->Call(global, kArgc, argv);
  return val;
}


void Shell::DispatchDebugMessages() {
  v8::Context::Scope scope(Shell::evaluation_context_);
  v8::Debug::ProcessDebugMessages();
}
#endif  // ENABLE_DEBUGGER_SUPPORT
#endif  // V8_SHARED


#ifndef V8_SHARED
int32_t* Counter::Bind(const char* name, bool is_histogram) {
  int i;
  for (i = 0; i < kMaxNameSize - 1 && name[i]; i++)
    name_[i] = static_cast<char>(name[i]);
  name_[i] = '\0';
  is_histogram_ = is_histogram;
  return ptr();
}


void Counter::AddSample(int32_t sample) {
  count_++;
  sample_total_ += sample;
}


CounterCollection::CounterCollection() {
  magic_number_ = 0xDEADFACE;
  max_counters_ = kMaxCounters;
  max_name_size_ = Counter::kMaxNameSize;
  counters_in_use_ = 0;
}


Counter* CounterCollection::GetNextCounter() {
  if (counters_in_use_ == kMaxCounters) return NULL;
  return &counters_[counters_in_use_++];
}


void Shell::MapCounters(const char* name) {
  counters_file_ = i::OS::MemoryMappedFile::create(
      name, sizeof(CounterCollection), &local_counters_);
  void* memory = (counters_file_ == NULL) ?
      NULL : counters_file_->memory();
  if (memory == NULL) {
    printf("Could not map counters file %s\n", name);
    Exit(1);
  }
  counters_ = static_cast<CounterCollection*>(memory);
  V8::SetCounterFunction(LookupCounter);
  V8::SetCreateHistogramFunction(CreateHistogram);
  V8::SetAddHistogramSampleFunction(AddHistogramSample);
}


int CounterMap::Hash(const char* name) {
  int h = 0;
  int c;
  while ((c = *name++) != 0) {
    h += h << 5;
    h += c;
  }
  return h;
}


Counter* Shell::GetCounter(const char* name, bool is_histogram) {
  Counter* counter = counter_map_->Lookup(name);

  if (counter == NULL) {
    counter = counters_->GetNextCounter();
    if (counter != NULL) {
      counter_map_->Set(name, counter);
      counter->Bind(name, is_histogram);
    }
  } else {
    ASSERT(counter->is_histogram() == is_histogram);
  }
  return counter;
}


int* Shell::LookupCounter(const char* name) {
  Counter* counter = GetCounter(name, false);

  if (counter != NULL) {
    return counter->ptr();
  } else {
    return NULL;
  }
}


void* Shell::CreateHistogram(const char* name,
                             int min,
                             int max,
                             size_t buckets) {
  return GetCounter(name, true);
}


void Shell::AddHistogramSample(void* histogram, int sample) {
  Counter* counter = reinterpret_cast<Counter*>(histogram);
  counter->AddSample(sample);
}


void Shell::InstallUtilityScript() {
  Locker lock;
  HandleScope scope;
  // If we use the utility context, we have to set the security tokens so that
  // utility, evaluation and debug context can all access each other.
  utility_context_->SetSecurityToken(Undefined());
  evaluation_context_->SetSecurityToken(Undefined());
  Context::Scope utility_scope(utility_context_);

#ifdef ENABLE_DEBUGGER_SUPPORT
  if (i::FLAG_debugger) printf("JavaScript debugger enabled\n");
  // Install the debugger object in the utility scope
  i::Debug* debug = i::Isolate::Current()->debug();
  debug->Load();
  i::Handle<i::JSObject> js_debug
      = i::Handle<i::JSObject>(debug->debug_context()->global());
  utility_context_->Global()->Set(String::New("$debug"),
                                  Utils::ToLocal(js_debug));
  debug->debug_context()->set_security_token(HEAP->undefined_value());
#endif  // ENABLE_DEBUGGER_SUPPORT

  // Run the d8 shell utility script in the utility context
  int source_index = i::NativesCollection<i::D8>::GetIndex("d8");
  i::Vector<const char> shell_source =
      i::NativesCollection<i::D8>::GetRawScriptSource(source_index);
  i::Vector<const char> shell_source_name =
      i::NativesCollection<i::D8>::GetScriptName(source_index);
  Handle<String> source = String::New(shell_source.start(),
      shell_source.length());
  Handle<String> name = String::New(shell_source_name.start(),
      shell_source_name.length());
  Handle<Script> script = Script::Compile(source, name);
  script->Run();
  // Mark the d8 shell script as native to avoid it showing up as normal source
  // in the debugger.
  i::Handle<i::Object> compiled_script = Utils::OpenHandle(*script);
  i::Handle<i::Script> script_object = compiled_script->IsJSFunction()
      ? i::Handle<i::Script>(i::Script::cast(
          i::JSFunction::cast(*compiled_script)->shared()->script()))
      : i::Handle<i::Script>(i::Script::cast(
          i::SharedFunctionInfo::cast(*compiled_script)->script()));
  script_object->set_type(i::Smi::FromInt(i::Script::TYPE_NATIVE));

#ifdef ENABLE_DEBUGGER_SUPPORT
  // Start the in-process debugger if requested.
  if (i::FLAG_debugger && !i::FLAG_debugger_agent) {
    v8::Debug::SetDebugEventListener(HandleDebugEvent);
  }
#endif  // ENABLE_DEBUGGER_SUPPORT
}
#endif  // V8_SHARED


#ifdef COMPRESS_STARTUP_DATA_BZ2
class BZip2Decompressor : public v8::StartupDataDecompressor {
 public:
  virtual ~BZip2Decompressor() { }

 protected:
  virtual int DecompressData(char* raw_data,
                             int* raw_data_size,
                             const char* compressed_data,
                             int compressed_data_size) {
    ASSERT_EQ(v8::StartupData::kBZip2,
              v8::V8::GetCompressedStartupDataAlgorithm());
    unsigned int decompressed_size = *raw_data_size;
    int result =
        BZ2_bzBuffToBuffDecompress(raw_data,
                                   &decompressed_size,
                                   const_cast<char*>(compressed_data),
                                   compressed_data_size,
                                   0, 1);
    if (result == BZ_OK) {
      *raw_data_size = decompressed_size;
    }
    return result;
  }
};
#endif


Handle<FunctionTemplate> Shell::CreateArrayBufferTemplate(
    InvocationCallback fun) {
  Handle<FunctionTemplate> buffer_template = FunctionTemplate::New(fun);
  Local<Template> proto_template = buffer_template->PrototypeTemplate();
  proto_template->Set(String::New("slice"),
                      FunctionTemplate::New(ArrayBufferSlice));
  return buffer_template;
}


Handle<FunctionTemplate> Shell::CreateArrayTemplate(InvocationCallback fun) {
  Handle<FunctionTemplate> array_template = FunctionTemplate::New(fun);
  Local<Template> proto_template = array_template->PrototypeTemplate();
  proto_template->Set(String::New("set"), FunctionTemplate::New(ArraySet));
  proto_template->Set(String::New("subarray"),
                      FunctionTemplate::New(ArraySubArray));
  return array_template;
}


Handle<ObjectTemplate> Shell::CreateGlobalTemplate() {
  Handle<ObjectTemplate> global_template = ObjectTemplate::New();
  global_template->Set(String::New("print"), FunctionTemplate::New(Print));
  global_template->Set(String::New("write"), FunctionTemplate::New(Write));
  global_template->Set(String::New("read"), FunctionTemplate::New(Read));
  global_template->Set(String::New("readbuffer"),
                       FunctionTemplate::New(ReadBuffer));
  global_template->Set(String::New("readline"),
                       FunctionTemplate::New(ReadLine));
  global_template->Set(String::New("load"), FunctionTemplate::New(Load));
  global_template->Set(String::New("quit"), FunctionTemplate::New(Quit));
  global_template->Set(String::New("version"), FunctionTemplate::New(Version));
  global_template->Set(String::New("enableProfiler"),
                       FunctionTemplate::New(EnableProfiler));
  global_template->Set(String::New("disableProfiler"),
                       FunctionTemplate::New(DisableProfiler));

  // Bind the handlers for external arrays.
  PropertyAttribute attr =
      static_cast<PropertyAttribute>(ReadOnly | DontDelete);
  global_template->Set(String::New("ArrayBuffer"),
                       CreateArrayBufferTemplate(ArrayBuffer), attr);
  global_template->Set(String::New("Int8Array"),
                       CreateArrayTemplate(Int8Array), attr);
  global_template->Set(String::New("Uint8Array"),
                       CreateArrayTemplate(Uint8Array), attr);
  global_template->Set(String::New("Int16Array"),
                       CreateArrayTemplate(Int16Array), attr);
  global_template->Set(String::New("Uint16Array"),
                       CreateArrayTemplate(Uint16Array), attr);
  global_template->Set(String::New("Int32Array"),
                       CreateArrayTemplate(Int32Array), attr);
  global_template->Set(String::New("Uint32Array"),
                       CreateArrayTemplate(Uint32Array), attr);
  global_template->Set(String::New("Float32Array"),
                       CreateArrayTemplate(Float32Array), attr);
  global_template->Set(String::New("Float64Array"),
                       CreateArrayTemplate(Float64Array), attr);
  global_template->Set(String::New("Uint8ClampedArray"),
                       CreateArrayTemplate(Uint8ClampedArray), attr);

#ifdef LIVE_OBJECT_LIST
  global_template->Set(String::New("lol_is_enabled"), True());
#else
  global_template->Set(String::New("lol_is_enabled"), False());
#endif

#if !defined(V8_SHARED) && !defined(_WIN32) && !defined(_WIN64)
  Handle<ObjectTemplate> os_templ = ObjectTemplate::New();
  AddOSMethods(os_templ);
  global_template->Set(String::New("os"), os_templ);
#endif  // V8_SHARED

  return global_template;
}


void Shell::Initialize() {
#ifdef COMPRESS_STARTUP_DATA_BZ2
  BZip2Decompressor startup_data_decompressor;
  int bz2_result = startup_data_decompressor.Decompress();
  if (bz2_result != BZ_OK) {
    fprintf(stderr, "bzip error code: %d\n", bz2_result);
    Exit(1);
  }
#endif

#ifndef V8_SHARED
  Shell::counter_map_ = new CounterMap();
  // Set up counters
  if (i::StrLength(i::FLAG_map_counters) != 0)
    MapCounters(i::FLAG_map_counters);
  if (i::FLAG_dump_counters) {
    V8::SetCounterFunction(LookupCounter);
    V8::SetCreateHistogramFunction(CreateHistogram);
    V8::SetAddHistogramSampleFunction(AddHistogramSample);
  }
#endif  // V8_SHARED
  if (options.test_shell) return;

#ifndef V8_SHARED
  Locker lock;
  HandleScope scope;
  Handle<ObjectTemplate> global_template = CreateGlobalTemplate();
  utility_context_ = Context::New(NULL, global_template);

#ifdef ENABLE_DEBUGGER_SUPPORT
  // Start the debugger agent if requested.
  if (i::FLAG_debugger_agent) {
    v8::Debug::EnableAgent("d8 shell", i::FLAG_debugger_port, true);
    v8::Debug::SetDebugMessageDispatchHandler(DispatchDebugMessages, true);
  }
#endif  // ENABLE_DEBUGGER_SUPPORT
#endif  // V8_SHARED
}


Persistent<Context> Shell::CreateEvaluationContext() {
#ifndef V8_SHARED
  // This needs to be a critical section since this is not thread-safe
  i::ScopedLock lock(context_mutex_);
#endif  // V8_SHARED
  // Initialize the global objects
  Handle<ObjectTemplate> global_template = CreateGlobalTemplate();
  Persistent<Context> context = Context::New(NULL, global_template);
  ASSERT(!context.IsEmpty());
  Context::Scope scope(context);

#ifndef V8_SHARED
  i::JSArguments js_args = i::FLAG_js_arguments;
  i::Handle<i::FixedArray> arguments_array =
      FACTORY->NewFixedArray(js_args.argc());
  for (int j = 0; j < js_args.argc(); j++) {
    i::Handle<i::String> arg =
        FACTORY->NewStringFromUtf8(i::CStrVector(js_args[j]));
    arguments_array->set(j, *arg);
  }
  i::Handle<i::JSArray> arguments_jsarray =
      FACTORY->NewJSArrayWithElements(arguments_array);
  context->Global()->Set(String::New("arguments"),
                         Utils::ToLocal(arguments_jsarray));
#endif  // V8_SHARED
  return context;
}


void Shell::Exit(int exit_code) {
  // Use _exit instead of exit to avoid races between isolate
  // threads and static destructors.
  fflush(stdout);
  fflush(stderr);
  _exit(exit_code);
}


#ifndef V8_SHARED
struct CounterAndKey {
  Counter* counter;
  const char* key;
};


int CompareKeys(const void* a, const void* b) {
  return strcmp(static_cast<const CounterAndKey*>(a)->key,
                static_cast<const CounterAndKey*>(b)->key);
}


void Shell::OnExit() {
  if (console != NULL) console->Close();
  if (i::FLAG_dump_counters) {
    int number_of_counters = 0;
    for (CounterMap::Iterator i(counter_map_); i.More(); i.Next()) {
      number_of_counters++;
    }
    CounterAndKey* counters = new CounterAndKey[number_of_counters];
    int j = 0;
    for (CounterMap::Iterator i(counter_map_); i.More(); i.Next(), j++) {
      counters[j].counter = i.CurrentValue();
      counters[j].key = i.CurrentKey();
    }
    qsort(counters, number_of_counters, sizeof(counters[0]), CompareKeys);
    printf("+----------------------------------------------------------------+"
           "-------------+\n");
    printf("| Name                                                           |"
           " Value       |\n");
    printf("+----------------------------------------------------------------+"
           "-------------+\n");
    for (j = 0; j < number_of_counters; j++) {
      Counter* counter = counters[j].counter;
      const char* key = counters[j].key;
      if (counter->is_histogram()) {
        printf("| c:%-60s | %11i |\n", key, counter->count());
        printf("| t:%-60s | %11i |\n", key, counter->sample_total());
      } else {
        printf("| %-62s | %11i |\n", key, counter->count());
      }
    }
    printf("+----------------------------------------------------------------+"
           "-------------+\n");
    delete [] counters;
  }
  delete counters_file_;
  delete counter_map_;
}
#endif  // V8_SHARED


static FILE* FOpen(const char* path, const char* mode) {
#if defined(_MSC_VER) && (defined(_WIN32) || defined(_WIN64))
  FILE* result;
  if (fopen_s(&result, path, mode) == 0) {
    return result;
  } else {
    return NULL;
  }
#else
  FILE* file = fopen(path, mode);
  if (file == NULL) return NULL;
  struct stat file_stat;
  if (fstat(fileno(file), &file_stat) != 0) return NULL;
  bool is_regular_file = ((file_stat.st_mode & S_IFREG) != 0);
  if (is_regular_file) return file;
  fclose(file);
  return NULL;
#endif
}


static char* ReadChars(const char* name, int* size_out) {
  // Release the V8 lock while reading files.
  v8::Unlocker unlocker(Isolate::GetCurrent());
  FILE* file = FOpen(name, "rb");
  if (file == NULL) return NULL;

  fseek(file, 0, SEEK_END);
  int size = ftell(file);
  rewind(file);

  char* chars = new char[size + 1];
  chars[size] = '\0';
  for (int i = 0; i < size;) {
    int read = static_cast<int>(fread(&chars[i], 1, size - i, file));
    i += read;
  }
  fclose(file);
  *size_out = size;
  return chars;
}


Handle<Value> Shell::ReadBuffer(const Arguments& args) {
  ASSERT(sizeof(char) == sizeof(uint8_t));  // NOLINT
  String::Utf8Value filename(args[0]);
  int length;
  if (*filename == NULL) {
    return ThrowException(String::New("Error loading file"));
  }

  uint8_t* data = reinterpret_cast<uint8_t*>(ReadChars(*filename, &length));
  if (data == NULL) {
    return ThrowException(String::New("Error reading file"));
  }
  Handle<Object> buffer = Object::New();
  buffer->SetHiddenValue(String::New(kArrayBufferMarkerPropName), True());
  Persistent<Object> persistent_buffer = Persistent<Object>::New(buffer);
  persistent_buffer.MakeWeak(data, ExternalArrayWeakCallback);
  persistent_buffer.MarkIndependent();
  V8::AdjustAmountOfExternalAllocatedMemory(length);

  buffer->SetIndexedPropertiesToExternalArrayData(
      data, kExternalUnsignedByteArray, length);
  buffer->Set(String::New("byteLength"),
      Int32::New(static_cast<int32_t>(length)), ReadOnly);
  return buffer;
}


#ifndef V8_SHARED
static char* ReadToken(char* data, char token) {
  char* next = i::OS::StrChr(data, token);
  if (next != NULL) {
    *next = '\0';
    return (next + 1);
  }

  return NULL;
}


static char* ReadLine(char* data) {
  return ReadToken(data, '\n');
}


static char* ReadWord(char* data) {
  return ReadToken(data, ' ');
}
#endif  // V8_SHARED


// Reads a file into a v8 string.
Handle<String> Shell::ReadFile(const char* name) {
  int size = 0;
  char* chars = ReadChars(name, &size);
  if (chars == NULL) return Handle<String>();
  Handle<String> result = String::New(chars);
  delete[] chars;
  return result;
}


void Shell::RunShell() {
  Locker locker;
  Context::Scope context_scope(evaluation_context_);
  HandleScope outer_scope;
  Handle<String> name = String::New("(d8)");
  console = LineEditor::Get();
  printf("V8 version %s [console: %s]\n", V8::GetVersion(), console->name());
  console->Open();
  while (true) {
    HandleScope inner_scope;
    Handle<String> input = console->Prompt(Shell::kPrompt);
    if (input.IsEmpty()) break;
    ExecuteString(input, name, true, true);
  }
  printf("\n");
}


#ifndef V8_SHARED
class ShellThread : public i::Thread {
 public:
  // Takes ownership of the underlying char array of |files|.
  ShellThread(int no, char* files)
      : Thread("d8:ShellThread"),
        no_(no), files_(files) { }

  ~ShellThread() {
    delete[] files_;
  }

  virtual void Run();
 private:
  int no_;
  char* files_;
};


void ShellThread::Run() {
  char* ptr = files_;
  while ((ptr != NULL) && (*ptr != '\0')) {
    // For each newline-separated line.
    char* next_line = ReadLine(ptr);

    if (*ptr == '#') {
      // Skip comment lines.
      ptr = next_line;
      continue;
    }

    // Prepare the context for this thread.
    Locker locker;
    HandleScope outer_scope;
    Persistent<Context> thread_context = Shell::CreateEvaluationContext();
    Context::Scope context_scope(thread_context);

    while ((ptr != NULL) && (*ptr != '\0')) {
      HandleScope inner_scope;
      char* filename = ptr;
      ptr = ReadWord(ptr);

      // Skip empty strings.
      if (strlen(filename) == 0) {
        continue;
      }

      Handle<String> str = Shell::ReadFile(filename);
      if (str.IsEmpty()) {
        printf("File '%s' not found\n", filename);
        Shell::Exit(1);
      }

      Shell::ExecuteString(str, String::New(filename), false, false);
    }

    thread_context.Dispose();
    ptr = next_line;
  }
}
#endif  // V8_SHARED


SourceGroup::~SourceGroup() {
#ifndef V8_SHARED
  delete next_semaphore_;
  next_semaphore_ = NULL;
  delete done_semaphore_;
  done_semaphore_ = NULL;
  delete thread_;
  thread_ = NULL;
#endif  // V8_SHARED
}


void SourceGroup::Execute() {
  for (int i = begin_offset_; i < end_offset_; ++i) {
    const char* arg = argv_[i];
    if (strcmp(arg, "-e") == 0 && i + 1 < end_offset_) {
      // Execute argument given to -e option directly.
      HandleScope handle_scope;
      Handle<String> file_name = String::New("unnamed");
      Handle<String> source = String::New(argv_[i + 1]);
      if (!Shell::ExecuteString(source, file_name, false, true)) {
        Shell::Exit(1);
      }
      ++i;
    } else if (arg[0] == '-') {
      // Ignore other options. They have been parsed already.
    } else {
      // Use all other arguments as names of files to load and run.
      HandleScope handle_scope;
      Handle<String> file_name = String::New(arg);
      Handle<String> source = ReadFile(arg);
      if (source.IsEmpty()) {
        printf("Error reading '%s'\n", arg);
        Shell::Exit(1);
      }
      if (!Shell::ExecuteString(source, file_name, false, true)) {
        Shell::Exit(1);
      }
    }
  }
}


Handle<String> SourceGroup::ReadFile(const char* name) {
  int size;
  char* chars = ReadChars(name, &size);
  if (chars == NULL) return Handle<String>();
  Handle<String> result = String::New(chars, size);
  delete[] chars;
  return result;
}


#ifndef V8_SHARED
i::Thread::Options SourceGroup::GetThreadOptions() {
  // On some systems (OSX 10.6) the stack size default is 0.5Mb or less
  // which is not enough to parse the big literal expressions used in tests.
  // The stack size should be at least StackGuard::kLimitSize + some
  // OS-specific padding for thread startup code.  2Mbytes seems to be enough.
  return i::Thread::Options("IsolateThread", 2 * MB);
}


void SourceGroup::ExecuteInThread() {
  Isolate* isolate = Isolate::New();
  do {
    if (next_semaphore_ != NULL) next_semaphore_->Wait();
    {
      Isolate::Scope iscope(isolate);
      Locker lock(isolate);
      HandleScope scope;
      Persistent<Context> context = Shell::CreateEvaluationContext();
      {
        Context::Scope cscope(context);
        Execute();
      }
      context.Dispose();
    }
    if (done_semaphore_ != NULL) done_semaphore_->Signal();
  } while (!Shell::options.last_run);
  isolate->Dispose();
}


void SourceGroup::StartExecuteInThread() {
  if (thread_ == NULL) {
    thread_ = new IsolateThread(this);
    thread_->Start();
  }
  next_semaphore_->Signal();
}


void SourceGroup::WaitForThread() {
  if (thread_ == NULL) return;
  if (Shell::options.last_run) {
    thread_->Join();
  } else {
    done_semaphore_->Wait();
  }
}
#endif  // V8_SHARED


bool Shell::SetOptions(int argc, char* argv[]) {
  for (int i = 0; i < argc; i++) {
    if (strcmp(argv[i], "--stress-opt") == 0) {
      options.stress_opt = true;
      argv[i] = NULL;
    } else if (strcmp(argv[i], "--stress-deopt") == 0) {
      options.stress_deopt = true;
      argv[i] = NULL;
    } else if (strcmp(argv[i], "--noalways-opt") == 0) {
      // No support for stressing if we can't use --always-opt.
      options.stress_opt = false;
      options.stress_deopt = false;
    } else if (strcmp(argv[i], "--shell") == 0) {
      options.interactive_shell = true;
      argv[i] = NULL;
    } else if (strcmp(argv[i], "--test") == 0) {
      options.test_shell = true;
      argv[i] = NULL;
    } else if (strcmp(argv[i], "--preemption") == 0) {
#ifdef V8_SHARED
      printf("D8 with shared library does not support multi-threading\n");
      return false;
#else
      options.use_preemption = true;
      argv[i] = NULL;
#endif  // V8_SHARED
    } else if (strcmp(argv[i], "--nopreemption") == 0) {
#ifdef V8_SHARED
      printf("D8 with shared library does not support multi-threading\n");
      return false;
#else
      options.use_preemption = false;
      argv[i] = NULL;
#endif  // V8_SHARED
    } else if (strcmp(argv[i], "--preemption-interval") == 0) {
#ifdef V8_SHARED
      printf("D8 with shared library does not support multi-threading\n");
      return false;
#else
      if (++i < argc) {
        argv[i-1] = NULL;
        char* end = NULL;
        options.preemption_interval = strtol(argv[i], &end, 10);  // NOLINT
        if (options.preemption_interval <= 0
            || *end != '\0'
            || errno == ERANGE) {
          printf("Invalid value for --preemption-interval '%s'\n", argv[i]);
          return false;
        }
        argv[i] = NULL;
      } else {
        printf("Missing value for --preemption-interval\n");
        return false;
      }
#endif  // V8_SHARED
    } else if (strcmp(argv[i], "-f") == 0) {
      // Ignore any -f flags for compatibility with other stand-alone
      // JavaScript engines.
      continue;
    } else if (strcmp(argv[i], "--isolate") == 0) {
#ifdef V8_SHARED
      printf("D8 with shared library does not support multi-threading\n");
      return false;
#endif  // V8_SHARED
      options.num_isolates++;
    } else if (strcmp(argv[i], "-p") == 0) {
#ifdef V8_SHARED
      printf("D8 with shared library does not support multi-threading\n");
      return false;
#else
      options.num_parallel_files++;
#endif  // V8_SHARED
    }
#ifdef V8_SHARED
    else if (strcmp(argv[i], "--dump-counters") == 0) {
      printf("D8 with shared library does not include counters\n");
      return false;
    } else if (strcmp(argv[i], "--debugger") == 0) {
      printf("Javascript debugger not included\n");
      return false;
    }
#endif  // V8_SHARED
  }

#ifndef V8_SHARED
  // Run parallel threads if we are not using --isolate
  options.parallel_files = new char*[options.num_parallel_files];
  int parallel_files_set = 0;
  for (int i = 1; i < argc; i++) {
    if (argv[i] == NULL) continue;
    if (strcmp(argv[i], "-p") == 0 && i + 1 < argc) {
      if (options.num_isolates > 1) {
        printf("-p is not compatible with --isolate\n");
        return false;
      }
      argv[i] = NULL;
      i++;
      options.parallel_files[parallel_files_set] = argv[i];
      parallel_files_set++;
      argv[i] = NULL;
    }
  }
  if (parallel_files_set != options.num_parallel_files) {
    printf("-p requires a file containing a list of files as parameter\n");
    return false;
  }
#endif  // V8_SHARED

  v8::V8::SetFlagsFromCommandLine(&argc, argv, true);

  // Set up isolated source groups.
  options.isolate_sources = new SourceGroup[options.num_isolates];
  SourceGroup* current = options.isolate_sources;
  current->Begin(argv, 1);
  for (int i = 1; i < argc; i++) {
    const char* str = argv[i];
    if (strcmp(str, "--isolate") == 0) {
      current->End(i);
      current++;
      current->Begin(argv, i + 1);
    } else if (strncmp(argv[i], "--", 2) == 0) {
      printf("Warning: unknown flag %s.\nTry --help for options\n", argv[i]);
    }
  }
  current->End(argc);

  return true;
}


int Shell::RunMain(int argc, char* argv[]) {
#ifndef V8_SHARED
  i::List<i::Thread*> threads(1);
  if (options.parallel_files != NULL) {
    for (int i = 0; i < options.num_parallel_files; i++) {
      char* files = NULL;
      { Locker lock(Isolate::GetCurrent());
        int size = 0;
        files = ReadChars(options.parallel_files[i], &size);
      }
      if (files == NULL) {
        printf("File list '%s' not found\n", options.parallel_files[i]);
        Exit(1);
      }
      ShellThread* thread = new ShellThread(threads.length(), files);
      thread->Start();
      threads.Add(thread);
    }
  }
  for (int i = 1; i < options.num_isolates; ++i) {
    options.isolate_sources[i].StartExecuteInThread();
  }
#endif  // V8_SHARED
  {  // NOLINT
    Locker lock;
    HandleScope scope;
    Persistent<Context> context = CreateEvaluationContext();
    if (options.last_run) {
      // Keep using the same context in the interactive shell.
      evaluation_context_ = context;
#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
      // If the interactive debugger is enabled make sure to activate
      // it before running the files passed on the command line.
      if (i::FLAG_debugger) {
        InstallUtilityScript();
      }
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT
    }
    {
      Context::Scope cscope(context);
      options.isolate_sources[0].Execute();
    }
    if (!options.last_run) {
      context.Dispose();
#if !defined(V8_SHARED)
      if (i::FLAG_send_idle_notification) {
        const int kLongIdlePauseInMs = 1000;
        V8::ContextDisposedNotification();
        V8::IdleNotification(kLongIdlePauseInMs);
      }
#endif  // !V8_SHARED
    }

#ifndef V8_SHARED
    // Start preemption if threads have been created and preemption is enabled.
    if (threads.length() > 0
        && options.use_preemption) {
      Locker::StartPreemption(options.preemption_interval);
    }
#endif  // V8_SHARED
  }

#ifndef V8_SHARED
  for (int i = 1; i < options.num_isolates; ++i) {
    options.isolate_sources[i].WaitForThread();
  }

  for (int i = 0; i < threads.length(); i++) {
    i::Thread* thread = threads[i];
    thread->Join();
    delete thread;
  }

  if (threads.length() > 0 && options.use_preemption) {
    Locker lock;
    Locker::StopPreemption();
  }
#endif  // V8_SHARED
  return 0;
}


int Shell::Main(int argc, char* argv[]) {
  if (!SetOptions(argc, argv)) return 1;
  Initialize();

  int result = 0;
  if (options.stress_opt || options.stress_deopt) {
    Testing::SetStressRunType(
        options.stress_opt ? Testing::kStressTypeOpt
                           : Testing::kStressTypeDeopt);
    int stress_runs = Testing::GetStressRuns();
    for (int i = 0; i < stress_runs && result == 0; i++) {
      printf("============ Stress %d/%d ============\n", i + 1, stress_runs);
      Testing::PrepareStressRun(i);
      options.last_run = (i == stress_runs - 1);
      result = RunMain(argc, argv);
    }
    printf("======== Full Deoptimization =======\n");
    Testing::DeoptimizeAll();
#if !defined(V8_SHARED)
  } else if (i::FLAG_stress_runs > 0) {
    int stress_runs = i::FLAG_stress_runs;
    for (int i = 0; i < stress_runs && result == 0; i++) {
      printf("============ Run %d/%d ============\n", i + 1, stress_runs);
      options.last_run = (i == stress_runs - 1);
      result = RunMain(argc, argv);
    }
#endif
  } else {
    result = RunMain(argc, argv);
  }


#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
  // Run remote debugger if requested, but never on --test
  if (i::FLAG_remote_debugger && !options.test_shell) {
    InstallUtilityScript();
    RunRemoteDebugger(i::FLAG_debugger_port);
    return 0;
  }
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT

  // Run interactive shell if explicitly requested or if no script has been
  // executed, but never on --test

  if (( options.interactive_shell
      || !options.script_executed )
      && !options.test_shell ) {
#if !defined(V8_SHARED) && defined(ENABLE_DEBUGGER_SUPPORT)
    if (!i::FLAG_debugger) {
      InstallUtilityScript();
    }
#endif  // !V8_SHARED && ENABLE_DEBUGGER_SUPPORT
    RunShell();
  }

  V8::Dispose();

#ifndef V8_SHARED
  OnExit();
#endif  // V8_SHARED

  return result;
}

}  // namespace v8


#ifndef GOOGLE3
int main(int argc, char* argv[]) {
  return v8::Shell::Main(argc, argv);
}
#endif

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