Move V8 to external/v8

Change-Id: If68025d67453785a651c5dfb34fad298c16676a4
diff --git a/src/d8.cc b/src/d8.cc
new file mode 100644
index 0000000..e4658b1
--- /dev/null
+++ b/src/d8.cc
@@ -0,0 +1,772 @@
+// Copyright 2009 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.
+
+
+#include <stdlib.h>
+#include <errno.h>
+
+#include "d8.h"
+#include "d8-debug.h"
+#include "debug.h"
+#include "api.h"
+#include "natives.h"
+#include "platform.h"
+
+
+namespace v8 {
+
+
+const char* Shell::kHistoryFileName = ".d8_history";
+const char* Shell::kPrompt = "d8> ";
+
+
+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 i::SmartPointer<char> Prompt(const char* prompt);
+};
+
+
+static DumbLineEditor dumb_line_editor;
+
+
+i::SmartPointer<char> DumbLineEditor::Prompt(const char* prompt) {
+  static const int kBufferSize = 256;
+  char buffer[kBufferSize];
+  printf("%s", prompt);
+  char* str = fgets(buffer, kBufferSize, stdin);
+  return i::SmartPointer<char>(str ? i::StrDup(str) : str);
+}
+
+
+CounterMap* Shell::counter_map_;
+i::OS::MemoryMappedFile* Shell::counters_file_ = NULL;
+CounterCollection Shell::local_counters_;
+CounterCollection* Shell::counters_ = &local_counters_;
+Persistent<Context> Shell::utility_context_;
+Persistent<Context> Shell::evaluation_context_;
+
+
+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;
+}
+
+
+// Converts a V8 value to a C string.
+const char* 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) {
+  HandleScope handle_scope;
+  TryCatch try_catch;
+  if (i::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 && !i::FLAG_debugger)
+      ReportException(&try_catch);
+    return false;
+  } else {
+    Handle<Value> result = script->Run();
+    if (result.IsEmpty()) {
+      // Print errors that happened during execution.
+      if (report_exceptions && !i::FLAG_debugger)
+        ReportException(&try_catch);
+      return false;
+    } else {
+      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);
+        const char* cstr = ToCString(str);
+        printf("%s\n", cstr);
+      }
+      return true;
+    }
+  }
+}
+
+
+Handle<Value> Shell::Print(const Arguments& args) {
+  Handle<Value> val = Write(args);
+  printf("\n");
+  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]);
+    fwrite(*str, sizeof(**str), str.length(), stdout);
+  }
+  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<Value> Shell::ReadLine(const Arguments& args) {
+  i::SmartPointer<char> line(i::ReadLine(""));
+  if (*line == NULL) {
+    return Null();
+  }
+  size_t len = strlen(*line);
+  if (len > 0 && line[len - 1] == '\n') {
+    --len;
+  }
+  return String::New(*line, len);
+}
+
+
+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, false)) {
+      return ThrowException(String::New("Error executing  file"));
+    }
+  }
+  return Undefined();
+}
+
+
+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();
+  OnExit();
+  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;
+  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");
+  }
+}
+
+
+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;
+}
+#endif
+
+
+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::Initialize() {
+  Shell::counter_map_ = new CounterMap();
+  // Set up counters
+  if (i::FLAG_map_counters != NULL)
+    MapCounters(i::FLAG_map_counters);
+  if (i::FLAG_dump_counters) {
+    V8::SetCounterFunction(LookupCounter);
+    V8::SetCreateHistogramFunction(CreateHistogram);
+    V8::SetAddHistogramSampleFunction(AddHistogramSample);
+  }
+
+  // Initialize the global objects
+  HandleScope scope;
+  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("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));
+
+  Handle<ObjectTemplate> os_templ = ObjectTemplate::New();
+  AddOSMethods(os_templ);
+  global_template->Set(String::New("os"), os_templ);
+
+  utility_context_ = Context::New(NULL, global_template);
+  utility_context_->SetSecurityToken(Undefined());
+  Context::Scope utility_scope(utility_context_);
+
+  i::JSArguments js_args = i::FLAG_js_arguments;
+  i::Handle<i::FixedArray> arguments_array =
+      i::Factory::NewFixedArray(js_args.argc());
+  for (int j = 0; j < js_args.argc(); j++) {
+    i::Handle<i::String> arg =
+        i::Factory::NewStringFromUtf8(i::CStrVector(js_args[j]));
+    arguments_array->set(j, *arg);
+  }
+  i::Handle<i::JSArray> arguments_jsarray =
+      i::Factory::NewJSArrayWithElements(arguments_array);
+  global_template->Set(String::New("arguments"),
+                       Utils::ToLocal(arguments_jsarray));
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  // Install the debugger object in the utility scope
+  i::Debug::Load();
+  i::JSObject* debug = i::Debug::debug_context()->global();
+  utility_context_->Global()->Set(String::New("$debug"),
+                                  Utils::ToLocal(&debug));
+#endif
+
+  // 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>::GetScriptSource(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::JSFunction> script_fun = Utils::OpenHandle(*script);
+  i::Handle<i::Script> script_object =
+      i::Handle<i::Script>(i::Script::cast(script_fun->shared()->script()));
+  script_object->set_type(i::Smi::FromInt(i::Script::TYPE_NATIVE));
+
+  // Create the evaluation context
+  evaluation_context_ = Context::New(NULL, global_template);
+  evaluation_context_->SetSecurityToken(Undefined());
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  // Set the security token of the debug context to allow access.
+  i::Debug::debug_context()->set_security_token(i::Heap::undefined_value());
+
+  // Start the debugger agent if requested.
+  if (i::FLAG_debugger_agent) {
+    v8::Debug::EnableAgent("d8 shell", i::FLAG_debugger_port);
+  }
+
+  // Start the in-process debugger if requested.
+  if (i::FLAG_debugger && !i::FLAG_debugger_agent) {
+    v8::Debug::SetDebugEventListener(HandleDebugEvent);
+  }
+#endif
+}
+
+
+void Shell::OnExit() {
+  if (i::FLAG_dump_counters) {
+    ::printf("+----------------------------------------+-------------+\n");
+    ::printf("| Name                                   | Value       |\n");
+    ::printf("+----------------------------------------+-------------+\n");
+    for (CounterMap::Iterator i(counter_map_); i.More(); i.Next()) {
+      Counter* counter = i.CurrentValue();
+      if (counter->is_histogram()) {
+        ::printf("| c:%-36s | %11i |\n", i.CurrentKey(), counter->count());
+        ::printf("| t:%-36s | %11i |\n",
+                 i.CurrentKey(),
+                 counter->sample_total());
+      } else {
+        ::printf("| %-38s | %11i |\n", i.CurrentKey(), counter->count());
+      }
+    }
+    ::printf("+----------------------------------------+-------------+\n");
+  }
+  if (counters_file_ != NULL)
+    delete counters_file_;
+}
+
+
+static char* ReadChars(const char* name, int* size_out) {
+  v8::Unlocker unlocker;  // Release the V8 lock while reading files.
+  FILE* file = i::OS::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 = fread(&chars[i], 1, size - i, file);
+    i += read;
+  }
+  fclose(file);
+  *size_out = size;
+  return chars;
+}
+
+
+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, ' ');
+}
+
+
+// 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() {
+  LineEditor* editor = LineEditor::Get();
+  printf("V8 version %s [console: %s]\n", V8::GetVersion(), editor->name());
+  editor->Open();
+  while (true) {
+    Locker locker;
+    HandleScope handle_scope;
+    Context::Scope context_scope(evaluation_context_);
+    i::SmartPointer<char> input = editor->Prompt(Shell::kPrompt);
+    if (input.is_empty())
+      break;
+    editor->AddHistory(*input);
+    Handle<String> name = String::New("(d8)");
+    ExecuteString(String::New(*input), name, true, true);
+  }
+  editor->Close();
+  printf("\n");
+}
+
+
+class ShellThread : public i::Thread {
+ public:
+  ShellThread(int no, i::Vector<const char> files)
+    : no_(no), files_(files) { }
+  virtual void Run();
+ private:
+  int no_;
+  i::Vector<const char> files_;
+};
+
+
+void ShellThread::Run() {
+  // Prepare the context for this thread.
+  Locker locker;
+  HandleScope scope;
+  Handle<ObjectTemplate> global_template = ObjectTemplate::New();
+  global_template->Set(String::New("print"),
+                       FunctionTemplate::New(Shell::Print));
+  global_template->Set(String::New("write"),
+                       FunctionTemplate::New(Shell::Write));
+  global_template->Set(String::New("read"),
+                       FunctionTemplate::New(Shell::Read));
+  global_template->Set(String::New("readline"),
+                       FunctionTemplate::New(Shell::ReadLine));
+  global_template->Set(String::New("load"),
+                       FunctionTemplate::New(Shell::Load));
+  global_template->Set(String::New("yield"),
+                       FunctionTemplate::New(Shell::Yield));
+  global_template->Set(String::New("version"),
+                       FunctionTemplate::New(Shell::Version));
+
+  char* ptr = const_cast<char*>(files_.start());
+  while ((ptr != NULL) && (*ptr != '\0')) {
+    // For each newline-separated line.
+    char* next_line = ReadLine(ptr);
+
+    if (*ptr == '#') {
+      // Skip comment lines.
+      ptr = next_line;
+      continue;
+    }
+
+    Persistent<Context> thread_context = Context::New(NULL, global_template);
+    thread_context->SetSecurityToken(Undefined());
+    Context::Scope context_scope(thread_context);
+
+    while ((ptr != NULL) && (*ptr != '\0')) {
+      char* filename = ptr;
+      ptr = ReadWord(ptr);
+
+      // Skip empty strings.
+      if (strlen(filename) == 0) {
+        break;
+      }
+
+      Handle<String> str = Shell::ReadFile(filename);
+      if (str.IsEmpty()) {
+        printf("WARNING: %s not found\n", filename);
+        break;
+      }
+
+      Shell::ExecuteString(str, String::New(filename), false, false);
+    }
+
+    thread_context.Dispose();
+    ptr = next_line;
+  }
+}
+
+
+int Shell::Main(int argc, char* argv[]) {
+  i::FlagList::SetFlagsFromCommandLine(&argc, argv, true);
+  if (i::FLAG_help) {
+    return 1;
+  }
+  Initialize();
+  bool run_shell = (argc == 1);
+
+  // Default use preemption if threads are created.
+  bool use_preemption = true;
+
+  // Default to use lowest possible thread preemption interval to test as many
+  // edgecases as possible.
+  int preemption_interval = 1;
+
+  i::List<i::Thread*> threads(1);
+
+  {
+    // Acquire the V8 lock once initialization has finished. Since the thread
+    // below may spawn new threads accessing V8 holding the V8 lock here is
+    // mandatory.
+    Locker locker;
+    Context::Scope context_scope(evaluation_context_);
+    for (int i = 1; i < argc; i++) {
+      char* str = argv[i];
+      if (strcmp(str, "--shell") == 0) {
+        run_shell = true;
+      } else if (strcmp(str, "--preemption") == 0) {
+        use_preemption = true;
+      } else if (strcmp(str, "--no-preemption") == 0) {
+        use_preemption = false;
+      } else if (strcmp(str, "--preemption-interval") == 0) {
+        if (i + 1 < argc) {
+          char* end = NULL;
+          preemption_interval = strtol(argv[++i], &end, 10);  // NOLINT
+          if (preemption_interval <= 0 || *end != '\0' || errno == ERANGE) {
+            printf("Invalid value for --preemption-interval '%s'\n", argv[i]);
+            return 1;
+          }
+        } else {
+          printf("Missing value for --preemption-interval\n");
+          return 1;
+       }
+      } else if (strcmp(str, "-f") == 0) {
+        // Ignore any -f flags for compatibility with other stand-alone
+        // JavaScript engines.
+        continue;
+      } else if (strncmp(str, "--", 2) == 0) {
+        printf("Warning: unknown flag %s.\nTry --help for options\n", str);
+      } else if (strcmp(str, "-e") == 0 && i + 1 < argc) {
+        // Execute argument given to -e option directly.
+        v8::HandleScope handle_scope;
+        v8::Handle<v8::String> file_name = v8::String::New("unnamed");
+        v8::Handle<v8::String> source = v8::String::New(argv[i + 1]);
+        if (!ExecuteString(source, file_name, false, true)) {
+          OnExit();
+          return 1;
+        }
+        i++;
+      } else if (strcmp(str, "-p") == 0 && i + 1 < argc) {
+        int size = 0;
+        const char* files = ReadChars(argv[++i], &size);
+        if (files == NULL) return 1;
+        ShellThread* thread =
+            new ShellThread(threads.length(),
+                            i::Vector<const char>(files, size));
+        thread->Start();
+        threads.Add(thread);
+      } else {
+        // Use all other arguments as names of files to load and run.
+        HandleScope handle_scope;
+        Handle<String> file_name = v8::String::New(str);
+        Handle<String> source = ReadFile(str);
+        if (source.IsEmpty()) {
+          printf("Error reading '%s'\n", str);
+          return 1;
+        }
+        if (!ExecuteString(source, file_name, false, true)) {
+          OnExit();
+          return 1;
+        }
+      }
+    }
+
+    // Start preemption if threads have been created and preemption is enabled.
+    if (threads.length() > 0 && use_preemption) {
+      Locker::StartPreemption(preemption_interval);
+    }
+
+#ifdef ENABLE_DEBUGGER_SUPPORT
+    // Run the remote debugger if requested.
+    if (i::FLAG_remote_debugger) {
+      RunRemoteDebugger(i::FLAG_debugger_port);
+      return 0;
+    }
+#endif
+  }
+  if (run_shell)
+    RunShell();
+  for (int i = 0; i < threads.length(); i++) {
+    i::Thread* thread = threads[i];
+    thread->Join();
+    delete thread;
+  }
+  OnExit();
+  return 0;
+}
+
+
+}  // namespace v8
+
+
+int main(int argc, char* argv[]) {
+  return v8::Shell::Main(argc, argv);
+}