runtime/bin/dartutils.h - sdk.git - Git at Google

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 #ifndef BIN_DARTUTILS_H_
 #define BIN_DARTUTILS_H_

 #include "include/dart_api.h"
 #include "include/dart_native_api.h"

 #include "platform/assert.h"
 #include "platform/globals.h"

 namespace dart {
 namespace bin {

 // Forward declarations.
 class File;
 class OSError;

 /* Handles error handles returned from Dart API functions.  If a value
  * is an error, uses Dart_PropagateError to throw it to the enclosing
  * Dart activation.  Otherwise, returns the original handle.
  *
  * This function can be used to wrap most API functions, but API
  * functions can also be nested without this error check, since all
  * API functions return any error handles passed in as arguments, unchanged.
  */
 static inline Dart_Handle ThrowIfError(Dart_Handle handle) {
   if (Dart_IsError(handle)) Dart_PropagateError(handle);
   return handle;
 }

 class CommandLineOptions {
  public:
   explicit CommandLineOptions(int max_count)
       : count_(0), max_count_(max_count), arguments_(NULL) {
     static const int kWordSize = sizeof(intptr_t);
     arguments_ = reinterpret_cast<const char **>(malloc(max_count * kWordSize));
     if (arguments_ == NULL) {
       max_count_ = 0;
     }
   }
   ~CommandLineOptions() {
     free(arguments_);
     count_ = 0;
     max_count_ = 0;
     arguments_ = NULL;
   }

   int count() const { return count_; }
   const char** arguments() const { return arguments_; }

   const char* GetArgument(int index) const {
     return (index >= 0 && index < count_) ? arguments_[index] : NULL;
   }
   void AddArgument(const char* argument) {
     if (count_ < max_count_) {
       arguments_[count_] = argument;
       count_ += 1;
     } else {
       abort();  // We should never get into this situation.
     }
   }

   void operator delete(void* pointer) { abort(); }

  private:
   void* operator new(size_t size);

   int count_;
   int max_count_;
   const char** arguments_;

   DISALLOW_COPY_AND_ASSIGN(CommandLineOptions);
 };


 class DartUtils {
  public:
   // TODO(turnidge): Clean up the implementations of these so that
   // they allow for proper error propagation.

   // Assumes that the value object is known to be an integer object
   // that fits in a signed 64-bit integer.
   static int64_t GetIntegerValue(Dart_Handle value_obj);
   // Assumes that the value object is known to be an intptr_t. This should
   // only be known when the value has been put into Dart as a pointer encoded
   // in a 64-bit integer. This is the case for file and directory operations.
   static intptr_t GetIntptrValue(Dart_Handle value_obj);
   // Checks that the value object is an integer object that fits in a
   // signed 64-bit integer. If it is, the value is returned in the
   // value out parameter and true is returned. Otherwise, false is
   // returned.
   static bool GetInt64Value(Dart_Handle value_obj, int64_t* value);
   static const char* GetStringValue(Dart_Handle str_obj);
   static bool GetBooleanValue(Dart_Handle bool_obj);
   static void SetIntegerField(Dart_Handle handle,
                               const char* name,
                               intptr_t val);
   static intptr_t GetIntegerField(Dart_Handle handle,
                                   const char* name);
   static void SetStringField(Dart_Handle handle,
                              const char* name,
                              const char* val);
   static bool IsDartSchemeURL(const char* url_name);
   static bool IsDartExtensionSchemeURL(const char* url_name);
   static bool IsDartIOLibURL(const char* url_name);
   static bool IsDartBuiltinLibURL(const char* url_name);
   static bool IsHttpSchemeURL(const char* url_name);
   static Dart_Handle CanonicalizeURL(CommandLineOptions* url_mapping,
                                      Dart_Handle library,
                                      const char* url_str);
   static void* OpenFile(const char* name, bool write);
   static void ReadFile(const uint8_t** data, intptr_t* file_len, void* stream);
   static void WriteFile(const void* buffer, intptr_t num_bytes, void* stream);
   static void CloseFile(void* stream);
   static Dart_Handle ReadStringFromFile(const char* filename);
   static Dart_Handle ReadStringFromHttp(const char* filename);
   static Dart_Handle LibraryTagHandler(Dart_LibraryTag tag,
                                        Dart_Handle library,
                                        Dart_Handle url);
   static Dart_Handle LoadScript(const char* script_uri,
                                 Dart_Handle builtin_lib);
   static Dart_Handle LoadScriptHttp(Dart_Handle script_uri,
                                     Dart_Handle builtin_lib);
   static Dart_Handle LoadSource(CommandLineOptions* url_mapping,
                                 Dart_Handle library,
                                 Dart_Handle url,
                                 Dart_LibraryTag tag,
                                 const char* filename);
   static Dart_Handle PrepareForScriptLoading(const char* package_root,
                                              Dart_Handle builtin_lib);

   static bool PostNull(Dart_Port port_id);
   static bool PostInt32(Dart_Port port_id, int32_t value);

   static Dart_Handle GetDartClass(const char* library_url,
                                   const char* class_name);
   // Create a new Dart OSError object with the current OS error.
   static Dart_Handle NewDartOSError();
   // Create a new Dart OSError object with the provided OS error.
   static Dart_Handle NewDartOSError(OSError* os_error);
   static Dart_Handle NewDartSocketException(const char* message,
                                             Dart_Handle os_error);
   static Dart_Handle NewDartExceptionWithMessage(const char* library_url,
                                                  const char* exception_name,
                                                  const char* message);
   static Dart_Handle NewDartArgumentError(const char* message);

   // Create a new Dart String object from a C String.
   static Dart_Handle NewString(const char* str) {
     ASSERT(str != NULL);
     return Dart_NewStringFromUTF8(reinterpret_cast<const uint8_t*>(str),
                                   strlen(str));
   }

   // Create a new Dart InternalError object with the provided message.
   static Dart_Handle NewInternalError(const char* message);

   static void SetOriginalWorkingDirectory();

   static const char* MapLibraryUrl(CommandLineOptions* url_mapping,
                                    const char* url_string);

   static Dart_Handle ResolveScriptUri(Dart_Handle script_uri,
                                       Dart_Handle builtin_lib);

   static Dart_Handle FilePathFromUri(Dart_Handle script_uri,
                                      Dart_Handle builtin_lib);

   static Dart_Handle ResolveUri(Dart_Handle library_url,
                                 Dart_Handle url,
                                 Dart_Handle builtin_lib);

   // Sniffs the specified text_buffer to see if it contains the magic number
   // representing a script snapshot. If the text_buffer is a script snapshot
   // the return value is an updated pointer to the text_buffer pointing past
   // the magic number value. The 'buffer_len' parameter is also appropriately
   // adjusted.
   static const uint8_t* SniffForMagicNumber(const uint8_t* text_buffer,
                                             intptr_t* buffer_len,
                                             bool* is_snapshot);

   // Write a magic number to indicate a script snapshot file.
   static void WriteMagicNumber(File* file);

   // Global state that stores the original working directory..
   static const char* original_working_directory;

   static const char* kDartScheme;
   static const char* kDartExtensionScheme;
   static const char* kAsyncLibURL;
   static const char* kBuiltinLibURL;
   static const char* kCoreLibURL;
   static const char* kIOLibURL;
   static const char* kIOLibPatchURL;
   static const char* kUriLibURL;
   static const char* kHttpScheme;

   static const char* kIdFieldName;

   static uint8_t magic_number[];

  private:
   static const char* GetCanonicalPath(const char* reference_dir,
                                       const char* filename);

   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(DartUtils);
 };


 class CObject {
  public:
   // These match the constants in sdk/lib/io/common.dart.
   static const int kSuccess = 0;
   static const int kArgumentError = 1;
   static const int kOSError = 2;
   static const int kFileClosedError = 3;

   explicit CObject(Dart_CObject *cobject) : cobject_(cobject) {}
   Dart_CObject_Type type() { return cobject_->type; }
   Dart_TypedData_Type byte_array_type() {
     ASSERT(type() == Dart_CObject_kTypedData ||
            type() == Dart_CObject_kExternalTypedData);
     return cobject_->value.as_typed_data.type;
   }

   bool IsNull() { return type() == Dart_CObject_kNull; }
   bool IsBool() { return type() == Dart_CObject_kBool; }
   bool IsInt32() { return type() == Dart_CObject_kInt32; }
   bool IsInt64() { return type() == Dart_CObject_kInt64; }
   bool IsInt32OrInt64() { return IsInt32() || IsInt64(); }
   bool IsIntptr() { return IsInt32OrInt64(); }
   bool IsBigint() { return type() == Dart_CObject_kBigint; }
   bool IsDouble() { return type() == Dart_CObject_kDouble; }
   bool IsString() { return type() == Dart_CObject_kString; }
   bool IsArray() { return type() == Dart_CObject_kArray; }
   bool IsTypedData() { return type() == Dart_CObject_kTypedData; }
   bool IsUint8Array() {
     return type() == Dart_CObject_kTypedData &&
            byte_array_type() == Dart_TypedData_kUint8;
   }

   bool IsTrue() {
     return type() == Dart_CObject_kBool && cobject_->value.as_bool;
   }

   bool IsFalse() {
     return type() == Dart_CObject_kBool && !cobject_->value.as_bool;
   }

   void* operator new(size_t size) {
     return Dart_ScopeAllocate(size);
   }

   static CObject* Null();
   static CObject* True();
   static CObject* False();
   static CObject* Bool(bool value);
   static Dart_CObject* NewInt32(int32_t value);
   static Dart_CObject* NewInt64(int64_t value);
   static Dart_CObject* NewIntptr(intptr_t value);
   // TODO(sgjesse): Add support for kBigint.
   static Dart_CObject* NewDouble(double value);
   static Dart_CObject* NewString(int length);
   static Dart_CObject* NewString(const char* str);
   static Dart_CObject* NewArray(int length);
   static Dart_CObject* NewUint8Array(int length);
   static Dart_CObject* NewExternalUint8Array(
       int64_t length, uint8_t* data, void* peer,
       Dart_WeakPersistentHandleFinalizer callback);
   static Dart_CObject* NewIOBuffer(int64_t length);
   static void FreeIOBufferData(Dart_CObject* object);

   Dart_CObject* AsApiCObject() { return cobject_; }

   // Create a new CObject array with an illegal arguments error.
   static CObject* IllegalArgumentError();
   // Create a new CObject array with a file closed error.
   static CObject* FileClosedError();
   // Create a new CObject array with the current OS error.
   static CObject* NewOSError();
   // Create a new CObject array with the specified OS error.
   static CObject* NewOSError(OSError* os_error);

  protected:
   CObject() : cobject_(NULL) {}
   Dart_CObject* cobject_;

  private:
   static Dart_CObject* New(Dart_CObject_Type type, int additional_bytes = 0);

   static Dart_CObject api_null_;
   static Dart_CObject api_true_;
   static Dart_CObject api_false_;
   static CObject null_;
   static CObject true_;
   static CObject false_;

  private:
   DISALLOW_COPY_AND_ASSIGN(CObject);
 };


 #define DECLARE_COBJECT_CONSTRUCTORS(t)                                        \
   explicit CObject##t(Dart_CObject *cobject) : CObject(cobject) {              \
     ASSERT(type() == Dart_CObject_k##t);                                       \
     cobject_ = cobject;                                                        \
   }                                                                            \
   explicit CObject##t(CObject* cobject) : CObject() {                          \
     ASSERT(cobject != NULL);                                                   \
     ASSERT(cobject->type() == Dart_CObject_k##t);                              \
     cobject_ = cobject->AsApiCObject();                                        \
   }                                                                            \


 #define DECLARE_COBJECT_TYPED_DATA_CONSTRUCTORS(t)                             \
   explicit CObject##t##Array(Dart_CObject *cobject) : CObject(cobject) {       \
     ASSERT(type() == Dart_CObject_kTypedData);                                 \
     ASSERT(byte_array_type() == Dart_TypedData_k##t);                          \
     cobject_ = cobject;                                                        \
   }                                                                            \
   explicit CObject##t##Array(CObject* cobject) : CObject() {                   \
     ASSERT(cobject != NULL);                                                   \
     ASSERT(cobject->type() == Dart_CObject_kTypedData);                        \
     ASSERT(cobject->byte_array_type() == Dart_TypedData_k##t);                 \
     cobject_ = cobject->AsApiCObject();                                        \
   }                                                                            \


 #define DECLARE_COBJECT_EXTERNAL_TYPED_DATA_CONSTRUCTORS(t)                    \
   explicit CObjectExternal##t##Array(Dart_CObject *cobject)                    \
       : CObject(cobject) {                                                     \
     ASSERT(type() == Dart_CObject_kExternalTypedData);                         \
     ASSERT(byte_array_type() == Dart_TypedData_k##t);                          \
     cobject_ = cobject;                                                        \
   }                                                                            \
   explicit CObjectExternal##t##Array(CObject* cobject) : CObject() {           \
     ASSERT(cobject != NULL);                                                   \
     ASSERT(cobject->type() == Dart_CObject_kExternalTypedData);                \
     ASSERT(cobject->byte_array_type() == Dart_TypedData_k##t);                 \
     cobject_ = cobject->AsApiCObject();                                        \
   }                                                                            \


 class CObjectBool : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Bool)

   bool Value() const { return cobject_->value.as_bool; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectBool);
 };


 class CObjectInt32 : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Int32)

   int32_t Value() const { return cobject_->value.as_int32; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectInt32);
 };


 class CObjectInt64 : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Int64)

   int64_t Value() const { return cobject_->value.as_int64; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectInt64);
 };


 class CObjectIntptr : public CObject {
  public:
   explicit CObjectIntptr(Dart_CObject *cobject) : CObject(cobject) {
     ASSERT(type() == Dart_CObject_kInt32 || type() == Dart_CObject_kInt64);
     cobject_ = cobject;
   }
   explicit CObjectIntptr(CObject* cobject) : CObject() {
     ASSERT(cobject != NULL);
     ASSERT(cobject->type() == Dart_CObject_kInt64 ||
            cobject->type() == Dart_CObject_kInt32);
     cobject_ = cobject->AsApiCObject();
   }

   intptr_t Value()  {
     intptr_t result;
     if (type() == Dart_CObject_kInt32) {
       result = cobject_->value.as_int32;
     } else {
       ASSERT(sizeof(result) == 8);
       result = static_cast<intptr_t>(cobject_->value.as_int64);
     }
     return result;
   }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectIntptr);
 };


 class CObjectBigint : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Bigint)

   char* Value() const { return cobject_->value.as_bigint; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectBigint);
 };


 class CObjectDouble : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Double)

   double Value() const { return cobject_->value.as_double; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectDouble);
 };


 class CObjectString : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(String)

   int Length() const { return strlen(cobject_->value.as_string); }
   char* CString() const { return cobject_->value.as_string; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectString);
 };


 class CObjectArray : public CObject {
  public:
   DECLARE_COBJECT_CONSTRUCTORS(Array)

   int Length() const { return cobject_->value.as_array.length; }
   CObject* operator[](int index) const {
     return new CObject(cobject_->value.as_array.values[index]);
   }
   void SetAt(int index, CObject* value) {
     cobject_->value.as_array.values[index] = value->AsApiCObject();
   }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectArray);
 };


 class CObjectTypedData : public CObject {
  public:
   explicit CObjectTypedData(Dart_CObject *cobject) : CObject(cobject) {
     ASSERT(type() == Dart_CObject_kTypedData);
     cobject_ = cobject;
   }
   explicit CObjectTypedData(CObject* cobject) : CObject() {
     ASSERT(cobject != NULL);
     ASSERT(cobject->type() == Dart_CObject_kTypedData);
     cobject_ = cobject->AsApiCObject();
   }

   Dart_TypedData_Type Type() const {
     return cobject_->value.as_typed_data.type;
   }
   int Length() const { return cobject_->value.as_typed_data.length; }
   uint8_t* Buffer() const { return cobject_->value.as_typed_data.values; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectTypedData);
 };


 class CObjectUint8Array : public CObject {
  public:
   DECLARE_COBJECT_TYPED_DATA_CONSTRUCTORS(Uint8)

   int Length() const { return cobject_->value.as_typed_data.length; }
   uint8_t* Buffer() const { return cobject_->value.as_typed_data.values; }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectUint8Array);
 };


 class CObjectExternalUint8Array : public CObject {
  public:
   DECLARE_COBJECT_EXTERNAL_TYPED_DATA_CONSTRUCTORS(Uint8)

   int Length() const { return cobject_->value.as_external_typed_data.length; }
   void SetLength(uint64_t length) {
     cobject_->value.as_external_typed_data.length = length;
   }
   uint8_t* Data() const { return cobject_->value.as_external_typed_data.data; }
   void* Peer() const { return cobject_->value.as_external_typed_data.peer; }
   Dart_WeakPersistentHandleFinalizer Callback() const {
     return cobject_->value.as_external_typed_data.callback;
   }

  private:
   DISALLOW_COPY_AND_ASSIGN(CObjectExternalUint8Array);
 };

 }  // namespace bin
 }  // namespace dart

 #endif  // BIN_DARTUTILS_H_
	// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	#ifndef BIN_DARTUTILS_H_
	#define BIN_DARTUTILS_H_

	#include "include/dart_api.h"
	#include "include/dart_native_api.h"

	#include "platform/assert.h"
	#include "platform/globals.h"

	namespace dart {
	namespace bin {

	// Forward declarations.
	class File;
	class OSError;

	/* Handles error handles returned from Dart API functions. If a value
	* is an error, uses Dart_PropagateError to throw it to the enclosing
	* Dart activation. Otherwise, returns the original handle.
	*
	* This function can be used to wrap most API functions, but API
	* functions can also be nested without this error check, since all
	* API functions return any error handles passed in as arguments, unchanged.
	*/
	static inline Dart_Handle ThrowIfError(Dart_Handle handle) {
	if (Dart_IsError(handle)) Dart_PropagateError(handle);
	return handle;
	}

	class CommandLineOptions {
	public:
	explicit CommandLineOptions(int max_count)
	: count_(0), max_count_(max_count), arguments_(NULL) {
	static const int kWordSize = sizeof(intptr_t);
	arguments_ = reinterpret_cast<const char *>(malloc(max_count kWordSize));
	if (arguments_ == NULL) {
	max_count_ = 0;
	}
	}
	~CommandLineOptions() {
	free(arguments_);
	count_ = 0;
	max_count_ = 0;
	arguments_ = NULL;
	}

	int count() const { return count_; }
	const char** arguments() const { return arguments_; }

	const char* GetArgument(int index) const {
	return (index >= 0 && index < count_) ? arguments_[index] : NULL;
	}
	void AddArgument(const char* argument) {
	if (count_ < max_count_) {
	arguments_[count_] = argument;
	count_ += 1;
	} else {
	abort(); // We should never get into this situation.
	}
	}

	void operator delete(void* pointer) { abort(); }

	private:
	void* operator new(size_t size);

	int count_;
	int max_count_;
	const char** arguments_;

	DISALLOW_COPY_AND_ASSIGN(CommandLineOptions);
	};


	class DartUtils {
	public:
	// TODO(turnidge): Clean up the implementations of these so that
	// they allow for proper error propagation.

	// Assumes that the value object is known to be an integer object
	// that fits in a signed 64-bit integer.
	static int64_t GetIntegerValue(Dart_Handle value_obj);
	// Assumes that the value object is known to be an intptr_t. This should
	// only be known when the value has been put into Dart as a pointer encoded
	// in a 64-bit integer. This is the case for file and directory operations.
	static intptr_t GetIntptrValue(Dart_Handle value_obj);
	// Checks that the value object is an integer object that fits in a
	// signed 64-bit integer. If it is, the value is returned in the
	// value out parameter and true is returned. Otherwise, false is
	// returned.
	static bool GetInt64Value(Dart_Handle value_obj, int64_t* value);
	static const char* GetStringValue(Dart_Handle str_obj);
	static bool GetBooleanValue(Dart_Handle bool_obj);
	static void SetIntegerField(Dart_Handle handle,
	const char* name,
	intptr_t val);
	static intptr_t GetIntegerField(Dart_Handle handle,
	const char* name);
	static void SetStringField(Dart_Handle handle,
	const char* name,
	const char* val);
	static bool IsDartSchemeURL(const char* url_name);
	static bool IsDartExtensionSchemeURL(const char* url_name);
	static bool IsDartIOLibURL(const char* url_name);
	static bool IsDartBuiltinLibURL(const char* url_name);
	static bool IsHttpSchemeURL(const char* url_name);
	static Dart_Handle CanonicalizeURL(CommandLineOptions* url_mapping,
	Dart_Handle library,
	const char* url_str);
	static void* OpenFile(const char* name, bool write);
	static void ReadFile(const uint8_t** data, intptr_t* file_len, void* stream);
	static void WriteFile(const void* buffer, intptr_t num_bytes, void* stream);
	static void CloseFile(void* stream);
	static Dart_Handle ReadStringFromFile(const char* filename);
	static Dart_Handle ReadStringFromHttp(const char* filename);
	static Dart_Handle LibraryTagHandler(Dart_LibraryTag tag,
	Dart_Handle library,
	Dart_Handle url);
	static Dart_Handle LoadScript(const char* script_uri,
	Dart_Handle builtin_lib);
	static Dart_Handle LoadScriptHttp(Dart_Handle script_uri,
	Dart_Handle builtin_lib);
	static Dart_Handle LoadSource(CommandLineOptions* url_mapping,
	Dart_Handle library,
	Dart_Handle url,
	Dart_LibraryTag tag,
	const char* filename);
	static Dart_Handle PrepareForScriptLoading(const char* package_root,
	Dart_Handle builtin_lib);

	static bool PostNull(Dart_Port port_id);
	static bool PostInt32(Dart_Port port_id, int32_t value);

	static Dart_Handle GetDartClass(const char* library_url,
	const char* class_name);
	// Create a new Dart OSError object with the current OS error.
	static Dart_Handle NewDartOSError();
	// Create a new Dart OSError object with the provided OS error.
	static Dart_Handle NewDartOSError(OSError* os_error);
	static Dart_Handle NewDartSocketException(const char* message,
	Dart_Handle os_error);
	static Dart_Handle NewDartExceptionWithMessage(const char* library_url,
	const char* exception_name,
	const char* message);
	static Dart_Handle NewDartArgumentError(const char* message);

	// Create a new Dart String object from a C String.
	static Dart_Handle NewString(const char* str) {
	ASSERT(str != NULL);
	return Dart_NewStringFromUTF8(reinterpret_cast<const uint8_t*>(str),
	strlen(str));
	}

	// Create a new Dart InternalError object with the provided message.
	static Dart_Handle NewInternalError(const char* message);

	static void SetOriginalWorkingDirectory();

	static const char* MapLibraryUrl(CommandLineOptions* url_mapping,
	const char* url_string);

	static Dart_Handle ResolveScriptUri(Dart_Handle script_uri,
	Dart_Handle builtin_lib);

	static Dart_Handle FilePathFromUri(Dart_Handle script_uri,
	Dart_Handle builtin_lib);

	static Dart_Handle ResolveUri(Dart_Handle library_url,
	Dart_Handle url,
	Dart_Handle builtin_lib);

	// Sniffs the specified text_buffer to see if it contains the magic number
	// representing a script snapshot. If the text_buffer is a script snapshot
	// the return value is an updated pointer to the text_buffer pointing past
	// the magic number value. The 'buffer_len' parameter is also appropriately
	// adjusted.
	static const uint8_t* SniffForMagicNumber(const uint8_t* text_buffer,
	intptr_t* buffer_len,
	bool* is_snapshot);

	// Write a magic number to indicate a script snapshot file.
	static void WriteMagicNumber(File* file);

	// Global state that stores the original working directory..
	static const char* original_working_directory;

	static const char* kDartScheme;
	static const char* kDartExtensionScheme;
	static const char* kAsyncLibURL;
	static const char* kBuiltinLibURL;
	static const char* kCoreLibURL;
	static const char* kIOLibURL;
	static const char* kIOLibPatchURL;
	static const char* kUriLibURL;
	static const char* kHttpScheme;

	static const char* kIdFieldName;

	static uint8_t magic_number[];

	private:
	static const char* GetCanonicalPath(const char* reference_dir,
	const char* filename);

	DISALLOW_ALLOCATION();
	DISALLOW_IMPLICIT_CONSTRUCTORS(DartUtils);
	};


	class CObject {
	public:
	// These match the constants in sdk/lib/io/common.dart.
	static const int kSuccess = 0;
	static const int kArgumentError = 1;
	static const int kOSError = 2;
	static const int kFileClosedError = 3;

	explicit CObject(Dart_CObject *cobject) : cobject_(cobject) {}
	Dart_CObject_Type type() { return cobject_->type; }
	Dart_TypedData_Type byte_array_type() {
	ASSERT(type() == Dart_CObject_kTypedData \|\|
	type() == Dart_CObject_kExternalTypedData);
	return cobject_->value.as_typed_data.type;
	}

	bool IsNull() { return type() == Dart_CObject_kNull; }
	bool IsBool() { return type() == Dart_CObject_kBool; }
	bool IsInt32() { return type() == Dart_CObject_kInt32; }
	bool IsInt64() { return type() == Dart_CObject_kInt64; }
	bool IsInt32OrInt64() { return IsInt32() \|\| IsInt64(); }
	bool IsIntptr() { return IsInt32OrInt64(); }
	bool IsBigint() { return type() == Dart_CObject_kBigint; }
	bool IsDouble() { return type() == Dart_CObject_kDouble; }
	bool IsString() { return type() == Dart_CObject_kString; }
	bool IsArray() { return type() == Dart_CObject_kArray; }
	bool IsTypedData() { return type() == Dart_CObject_kTypedData; }
	bool IsUint8Array() {
	return type() == Dart_CObject_kTypedData &&
	byte_array_type() == Dart_TypedData_kUint8;
	}

	bool IsTrue() {
	return type() == Dart_CObject_kBool && cobject_->value.as_bool;
	}

	bool IsFalse() {
	return type() == Dart_CObject_kBool && !cobject_->value.as_bool;
	}

	void* operator new(size_t size) {
	return Dart_ScopeAllocate(size);
	}

	static CObject* Null();
	static CObject* True();
	static CObject* False();
	static CObject* Bool(bool value);
	static Dart_CObject* NewInt32(int32_t value);
	static Dart_CObject* NewInt64(int64_t value);
	static Dart_CObject* NewIntptr(intptr_t value);
	// TODO(sgjesse): Add support for kBigint.
	static Dart_CObject* NewDouble(double value);
	static Dart_CObject* NewString(int length);
	static Dart_CObject* NewString(const char* str);
	static Dart_CObject* NewArray(int length);
	static Dart_CObject* NewUint8Array(int length);
	static Dart_CObject* NewExternalUint8Array(
	int64_t length, uint8_t* data, void* peer,
	Dart_WeakPersistentHandleFinalizer callback);
	static Dart_CObject* NewIOBuffer(int64_t length);
	static void FreeIOBufferData(Dart_CObject* object);

	Dart_CObject* AsApiCObject() { return cobject_; }

	// Create a new CObject array with an illegal arguments error.
	static CObject* IllegalArgumentError();
	// Create a new CObject array with a file closed error.
	static CObject* FileClosedError();
	// Create a new CObject array with the current OS error.
	static CObject* NewOSError();
	// Create a new CObject array with the specified OS error.
	static CObject* NewOSError(OSError* os_error);

	protected:
	CObject() : cobject_(NULL) {}
	Dart_CObject* cobject_;

	private:
	static Dart_CObject* New(Dart_CObject_Type type, int additional_bytes = 0);

	static Dart_CObject api_null_;
	static Dart_CObject api_true_;
	static Dart_CObject api_false_;
	static CObject null_;
	static CObject true_;
	static CObject false_;

	private:
	DISALLOW_COPY_AND_ASSIGN(CObject);
	};


	#define DECLARE_COBJECT_CONSTRUCTORS(t) \
	explicit CObject##t(Dart_CObject *cobject) : CObject(cobject) { \
	ASSERT(type() == Dart_CObject_k##t); \
	cobject_ = cobject; \
	} \
	explicit CObject##t(CObject* cobject) : CObject() { \
	ASSERT(cobject != NULL); \
	ASSERT(cobject->type() == Dart_CObject_k##t); \
	cobject_ = cobject->AsApiCObject(); \
	} \


	#define DECLARE_COBJECT_TYPED_DATA_CONSTRUCTORS(t) \
	explicit CObject##t##Array(Dart_CObject *cobject) : CObject(cobject) { \
	ASSERT(type() == Dart_CObject_kTypedData); \
	ASSERT(byte_array_type() == Dart_TypedData_k##t); \
	cobject_ = cobject; \
	} \
	explicit CObject##t##Array(CObject* cobject) : CObject() { \
	ASSERT(cobject != NULL); \
	ASSERT(cobject->type() == Dart_CObject_kTypedData); \
	ASSERT(cobject->byte_array_type() == Dart_TypedData_k##t); \
	cobject_ = cobject->AsApiCObject(); \
	} \


	#define DECLARE_COBJECT_EXTERNAL_TYPED_DATA_CONSTRUCTORS(t) \
	explicit CObjectExternal##t##Array(Dart_CObject *cobject) \
	: CObject(cobject) { \
	ASSERT(type() == Dart_CObject_kExternalTypedData); \
	ASSERT(byte_array_type() == Dart_TypedData_k##t); \
	cobject_ = cobject; \
	} \
	explicit CObjectExternal##t##Array(CObject* cobject) : CObject() { \
	ASSERT(cobject != NULL); \
	ASSERT(cobject->type() == Dart_CObject_kExternalTypedData); \
	ASSERT(cobject->byte_array_type() == Dart_TypedData_k##t); \
	cobject_ = cobject->AsApiCObject(); \
	} \


	class CObjectBool : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Bool)

	bool Value() const { return cobject_->value.as_bool; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectBool);
	};


	class CObjectInt32 : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Int32)

	int32_t Value() const { return cobject_->value.as_int32; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectInt32);
	};


	class CObjectInt64 : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Int64)

	int64_t Value() const { return cobject_->value.as_int64; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectInt64);
	};


	class CObjectIntptr : public CObject {
	public:
	explicit CObjectIntptr(Dart_CObject *cobject) : CObject(cobject) {
	ASSERT(type() == Dart_CObject_kInt32 \|\| type() == Dart_CObject_kInt64);
	cobject_ = cobject;
	}
	explicit CObjectIntptr(CObject* cobject) : CObject() {
	ASSERT(cobject != NULL);
	ASSERT(cobject->type() == Dart_CObject_kInt64 \|\|
	cobject->type() == Dart_CObject_kInt32);
	cobject_ = cobject->AsApiCObject();
	}

	intptr_t Value() {
	intptr_t result;
	if (type() == Dart_CObject_kInt32) {
	result = cobject_->value.as_int32;
	} else {
	ASSERT(sizeof(result) == 8);
	result = static_cast<intptr_t>(cobject_->value.as_int64);
	}
	return result;
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectIntptr);
	};


	class CObjectBigint : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Bigint)

	char* Value() const { return cobject_->value.as_bigint; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectBigint);
	};


	class CObjectDouble : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Double)

	double Value() const { return cobject_->value.as_double; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectDouble);
	};


	class CObjectString : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(String)

	int Length() const { return strlen(cobject_->value.as_string); }
	char* CString() const { return cobject_->value.as_string; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectString);
	};


	class CObjectArray : public CObject {
	public:
	DECLARE_COBJECT_CONSTRUCTORS(Array)

	int Length() const { return cobject_->value.as_array.length; }
	CObject* operator[](int index) const {
	return new CObject(cobject_->value.as_array.values[index]);
	}
	void SetAt(int index, CObject* value) {
	cobject_->value.as_array.values[index] = value->AsApiCObject();
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectArray);
	};


	class CObjectTypedData : public CObject {
	public:
	explicit CObjectTypedData(Dart_CObject *cobject) : CObject(cobject) {
	ASSERT(type() == Dart_CObject_kTypedData);
	cobject_ = cobject;
	}
	explicit CObjectTypedData(CObject* cobject) : CObject() {
	ASSERT(cobject != NULL);
	ASSERT(cobject->type() == Dart_CObject_kTypedData);
	cobject_ = cobject->AsApiCObject();
	}

	Dart_TypedData_Type Type() const {
	return cobject_->value.as_typed_data.type;
	}
	int Length() const { return cobject_->value.as_typed_data.length; }
	uint8_t* Buffer() const { return cobject_->value.as_typed_data.values; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectTypedData);
	};


	class CObjectUint8Array : public CObject {
	public:
	DECLARE_COBJECT_TYPED_DATA_CONSTRUCTORS(Uint8)

	int Length() const { return cobject_->value.as_typed_data.length; }
	uint8_t* Buffer() const { return cobject_->value.as_typed_data.values; }

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectUint8Array);
	};


	class CObjectExternalUint8Array : public CObject {
	public:
	DECLARE_COBJECT_EXTERNAL_TYPED_DATA_CONSTRUCTORS(Uint8)

	int Length() const { return cobject_->value.as_external_typed_data.length; }
	void SetLength(uint64_t length) {
	cobject_->value.as_external_typed_data.length = length;
	}
	uint8_t* Data() const { return cobject_->value.as_external_typed_data.data; }
	void* Peer() const { return cobject_->value.as_external_typed_data.peer; }
	Dart_WeakPersistentHandleFinalizer Callback() const {
	return cobject_->value.as_external_typed_data.callback;
	}

	private:
	DISALLOW_COPY_AND_ASSIGN(CObjectExternalUint8Array);
	};

	} // namespace bin
	} // namespace dart

	#endif // BIN_DARTUTILS_H_