CSE2410 Fall 2014 Bounce

// 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.

// Platform specific code for Win32.

// Secure API functions are not available using MinGW with msvcrt.dll

// on Windows XP. Make sure MINGW_HAS_SECURE_API is not defined to

// disable definition of secure API functions in standard headers that

// would conflict with our own implementation.

#ifdef __MINGW32__

#include <_mingw.h>

#ifdef MINGW_HAS_SECURE_API

#undef MINGW_HAS_SECURE_API

#endif  // MINGW_HAS_SECURE_API

#endif  // __MINGW32__

#include "win32-headers.h"

#include "v8.h"

#include "codegen.h"

#include "isolate-inl.h"

#include "platform.h"

#include "simulator.h"

#include "vm-state-inl.h"

#ifdef _MSC_VER

// Case-insensitive bounded string comparisons. Use stricmp() on Win32. Usually

// defined in strings.h.

int strncasecmp(const char* s1, const char* s2, int n) {

  return _strnicmp(s1, s2, n);

}

#endif  // _MSC_VER

// Extra functions for MinGW. Most of these are the _s functions which are in

// the Microsoft Visual Studio C++ CRT.

#ifdef __MINGW32__

#ifndef __MINGW64_VERSION_MAJOR

#define _TRUNCATE 0

#define STRUNCATE 80

inline void MemoryBarrier() {

  int barrier = 0;

  __asm__ __volatile__("xchgl %%eax,%0 ":"=r" (barrier));

}

#endif  // __MINGW64_VERSION_MAJOR

int localtime_s(tm* out_tm, const time_t* time) {

  tm* posix_local_time_struct = localtime(time);

  if (posix_local_time_struct == NULL) return 1;

  *out_tm = *posix_local_time_struct;

  return 0;

}

int fopen_s(FILE** pFile, const char* filename, const char* mode) {

  *pFile = fopen(filename, mode);

  return *pFile != NULL ? 0 : 1;

}

int _vsnprintf_s(char* buffer, size_t sizeOfBuffer, size_t count,

                 const char* format, va_list argptr) {

  ASSERT(count == _TRUNCATE);

  return _vsnprintf(buffer, sizeOfBuffer, format, argptr);

}

int strncpy_s(char* dest, size_t dest_size, const char* source, size_t count) {

  CHECK(source != NULL);

  CHECK(dest != NULL);

  CHECK_GT(dest_size, 0);

  if (count == _TRUNCATE) {

    while (dest_size > 0 && *source != 0) {

      *(dest++) = *(source++);

      --dest_size;

    }

    if (dest_size == 0) {

      *(dest - 1) = 0;

      return STRUNCATE;

    }

  } else {

    while (dest_size > 0 && count > 0 && *source != 0) {

      *(dest++) = *(source++);

      --dest_size;

      --count;

    }

  }

  CHECK_GT(dest_size, 0);

  *dest = 0;

  return 0;

}

#endif  // __MINGW32__

namespace v8 {

namespace internal {

intptr_t OS::MaxVirtualMemory() {

  return 0;

}

double ceiling(double x) {

  return ceil(x);

}

#if V8_TARGET_ARCH_IA32

static void MemMoveWrapper(void* dest, const void* src, size_t size) {

  memmove(dest, src, size);

}

// Initialize to library version so we can call this at any time during startup.

static OS::MemMoveFunction memmove_function = &MemMoveWrapper;

// Defined in codegen-ia32.cc.

OS::MemMoveFunction CreateMemMoveFunction();

// Copy memory area to disjoint memory area.

void OS::MemMove(void* dest, const void* src, size_t size) {

  if (size == 0) return;

  // Note: here we rely on dependent reads being ordered. This is true

  // on all architectures we currently support.

  (*memmove_function)(dest, src, size);

}

#endif  // V8_TARGET_ARCH_IA32

#ifdef _WIN64

typedef double (*ModuloFunction)(double, double);

static ModuloFunction modulo_function = NULL;

// Defined in codegen-x64.cc.

ModuloFunction CreateModuloFunction();

void init_modulo_function() {

  modulo_function = CreateModuloFunction();

}

double modulo(double x, double y) {

  // Note: here we rely on dependent reads being ordered. This is true

  // on all architectures we currently support.

  return (*modulo_function)(x, y);

}

#else  // Win32

double modulo(double x, double y) {

  // Workaround MS fmod bugs. ECMA-262 says:

  // dividend is finite and divisor is an infinity => result equals dividend

  // dividend is a zero and divisor is nonzero finite => result equals dividend

  if (!(std::isfinite(x) && (!std::isfinite(y) && !std::isnan(y))) &&

      !(x == 0 && (y != 0 && std::isfinite(y)))) {

    x = fmod(x, y);

  }

  return x;

}

#endif  // _WIN64

#define UNARY_MATH_FUNCTION(name, generator)             \

static UnaryMathFunction fast_##name##_function = NULL;  \

void init_fast_##name##_function() {                     \

  fast_##name##_function = generator;                    \

}                                                        \

double fast_##name(double x) {                           \

  return (*fast_##name##_function)(x);                   \

}

UNARY_MATH_FUNCTION(sin, CreateTranscendentalFunction(TranscendentalCache::SIN))

UNARY_MATH_FUNCTION(cos, CreateTranscendentalFunction(TranscendentalCache::COS))

UNARY_MATH_FUNCTION(tan, CreateTranscendentalFunction(TranscendentalCache::TAN))

UNARY_MATH_FUNCTION(log, CreateTranscendentalFunction(TranscendentalCache::LOG))

UNARY_MATH_FUNCTION(exp, CreateExpFunction())

UNARY_MATH_FUNCTION(sqrt, CreateSqrtFunction())

#undef UNARY_MATH_FUNCTION

void lazily_initialize_fast_exp() {

  if (fast_exp_function == NULL) {

    init_fast_exp_function();

  }

}

void MathSetup() {

#ifdef _WIN64

  init_modulo_function();

#endif

  init_fast_sin_function();

  init_fast_cos_function();

  init_fast_tan_function();

  init_fast_log_function();

  // fast_exp is initialized lazily.

  init_fast_sqrt_function();

}

// ----------------------------------------------------------------------------

// The Time class represents time on win32. A timestamp is represented as

// a 64-bit integer in 100 nanoseconds since January 1, 1601 (UTC). JavaScript

// timestamps are represented as a doubles in milliseconds since 00:00:00 UTC,

// January 1, 1970.

class Win32Time {

 public:

  // Constructors.

  Win32Time();

  explicit Win32Time(double jstime);

  Win32Time(int year, int mon, int day, int hour, int min, int sec);

  // Convert timestamp to JavaScript representation.

  double ToJSTime();

  // Set timestamp to current time.

  void SetToCurrentTime();

  // Returns the local timezone offset in milliseconds east of UTC. This is

  // the number of milliseconds you must add to UTC to get local time, i.e.

  // LocalOffset(CET) = 3600000 and LocalOffset(PST) = -28800000. This

  // routine also takes into account whether daylight saving is effect

  // at the time.

  int64_t LocalOffset();

  // Returns the daylight savings time offset for the time in milliseconds.

  int64_t DaylightSavingsOffset();

  // Returns a string identifying the current timezone for the

  // timestamp taking into account daylight saving.

  char* LocalTimezone();

 private:

  // Constants for time conversion.

  static const int64_t kTimeEpoc = 116444736000000000LL;

  static const int64_t kTimeScaler = 10000;

  static const int64_t kMsPerMinute = 60000;

  // Constants for timezone information.

  static const int kTzNameSize = 128;

  static const bool kShortTzNames = false;

  // Timezone information. We need to have static buffers for the

  // timezone names because we return pointers to these in

  // LocalTimezone().

  static bool tz_initialized_;

  static TIME_ZONE_INFORMATION tzinfo_;

  static char std_tz_name_[kTzNameSize];

  static char dst_tz_name_[kTzNameSize];

  // Initialize the timezone information (if not already done).

  static void TzSet();

  // Guess the name of the timezone from the bias.

  static const char* GuessTimezoneNameFromBias(int bias);

  // Return whether or not daylight savings time is in effect at this time.

  bool InDST();

  // Accessor for FILETIME representation.

  FILETIME& ft() { return time_.ft_; }

  // Accessor for integer representation.

  int64_t& t() { return time_.t_; }

  // Although win32 uses 64-bit integers for representing timestamps,

  // these are packed into a FILETIME structure. The FILETIME structure

  // is just a struct representing a 64-bit integer. The TimeStamp union

  // allows access to both a FILETIME and an integer representation of

  // the timestamp.

  union TimeStamp {

    FILETIME ft_;

    int64_t t_;

  };

  TimeStamp time_;

};

// Static variables.

bool Win32Time::tz_initialized_ = false;

TIME_ZONE_INFORMATION Win32Time::tzinfo_;

char Win32Time::std_tz_name_[kTzNameSize];

char Win32Time::dst_tz_name_[kTzNameSize];

// Initialize timestamp to start of epoc.

Win32Time::Win32Time() {

  t() = 0;

}

// Initialize timestamp from a JavaScript timestamp.

Win32Time::Win32Time(double jstime) {

  t() = static_cast<int64_t>(jstime) * kTimeScaler + kTimeEpoc;

}

// Initialize timestamp from date/time components.

Win32Time::Win32Time(int year, int mon, int day, int hour, int min, int sec) {

  SYSTEMTIME st;

  st.wYear = year;

  st.wMonth = mon;

  st.wDay = day;

  st.wHour = hour;

  st.wMinute = min;

  st.wSecond = sec;

  st.wMilliseconds = 0;

  SystemTimeToFileTime(&st, &ft());

}

// Convert timestamp to JavaScript timestamp.

double Win32Time::ToJSTime() {

  return static_cast<double>((t() - kTimeEpoc) / kTimeScaler);

}

// Set timestamp to current time.

void Win32Time::SetToCurrentTime() {

  // The default GetSystemTimeAsFileTime has a ~15.5ms resolution.

  // Because we're fast, we like fast timers which have at least a

  // 1ms resolution.

  //

  // timeGetTime() provides 1ms granularity when combined with

  // timeBeginPeriod().  If the host application for v8 wants fast

  // timers, it can use timeBeginPeriod to increase the resolution.

  //

  // Using timeGetTime() has a drawback because it is a 32bit value

  // and hence rolls-over every ~49days.

  //

  // To use the clock, we use GetSystemTimeAsFileTime as our base;

  // and then use timeGetTime to extrapolate current time from the

  // start time.  To deal with rollovers, we resync the clock

  // any time when more than kMaxClockElapsedTime has passed or

  // whenever timeGetTime creates a rollover.

  static bool initialized = false;

  static TimeStamp init_time;

  static DWORD init_ticks;

  static const int64_t kHundredNanosecondsPerSecond = 10000000;

  static const int64_t kMaxClockElapsedTime =

      60*kHundredNanosecondsPerSecond;  // 1 minute

  // If we are uninitialized, we need to resync the clock.

  bool needs_resync = !initialized;

  // Get the current time.

  TimeStamp time_now;

  GetSystemTimeAsFileTime(&time_now.ft_);

  DWORD ticks_now = timeGetTime();

  // Check if we need to resync due to clock rollover.

  needs_resync |= ticks_now < init_ticks;

  // Check if we need to resync due to elapsed time.

  needs_resync |= (time_now.t_ - init_time.t_) > kMaxClockElapsedTime;

  // Check if we need to resync due to backwards time change.

  needs_resync |= time_now.t_ < init_time.t_;

  // Resync the clock if necessary.

  if (needs_resync) {

    GetSystemTimeAsFileTime(&init_time.ft_);

    init_ticks = ticks_now = timeGetTime();

    initialized = true;

  }

  // Finally, compute the actual time.  Why is this so hard.

  DWORD elapsed = ticks_now - init_ticks;

  this->time_.t_ = init_time.t_ + (static_cast<int64_t>(elapsed) * 10000);

}

// Guess the name of the timezone from the bias.

// The guess is very biased towards the northern hemisphere.

const char* Win32Time::GuessTimezoneNameFromBias(int bias) {

  static const int kHour = 60;

  switch (-bias) {

    case -9*kHour: return "Alaska";

    case -8*kHour: return "Pacific";

    case -7*kHour: return "Mountain";

    case -6*kHour: return "Central";

    case -5*kHour: return "Eastern";

    case -4*kHour: return "Atlantic";

    case  0*kHour: return "GMT";

    case +1*kHour: return "Central Europe";

    case +2*kHour: return "Eastern Europe";

    case +3*kHour: return "Russia";

    case +5*kHour + 30: return "India";

    case +8*kHour: return "China";

    case +9*kHour: return "Japan";

    case +12*kHour: return "New Zealand";

    default: return "Local";

  }

}

// Initialize timezone information. The timezone information is obtained from

// windows. If we cannot get the timezone information we fall back to CET.

// Please notice that this code is not thread-safe.

void Win32Time::TzSet() {

  // Just return if timezone information has already been initialized.

  if (tz_initialized_) return;

  // Initialize POSIX time zone data.

  _tzset();

  // Obtain timezone information from operating system.

  memset(&tzinfo_, 0, sizeof(tzinfo_));

  if (GetTimeZoneInformation(&tzinfo_) == TIME_ZONE_ID_INVALID) {

    // If we cannot get timezone information we fall back to CET.

    tzinfo_.Bias = -60;

    tzinfo_.StandardDate.wMonth = 10;

    tzinfo_.StandardDate.wDay = 5;

    tzinfo_.StandardDate.wHour = 3;

    tzinfo_.StandardBias = 0;

    tzinfo_.DaylightDate.wMonth = 3;

    tzinfo_.DaylightDate.wDay = 5;

    tzinfo_.DaylightDate.wHour = 2;

    tzinfo_.DaylightBias = -60;

  }

  // Make standard and DST timezone names.

  WideCharToMultiByte(CP_UTF8, 0, tzinfo_.StandardName, -1,

                      std_tz_name_, kTzNameSize, NULL, NULL);

  std_tz_name_[kTzNameSize - 1] = '\0';

  WideCharToMultiByte(CP_UTF8, 0, tzinfo_.DaylightName, -1,

                      dst_tz_name_, kTzNameSize, NULL, NULL);

  dst_tz_name_[kTzNameSize - 1] = '\0';

  // If OS returned empty string or resource id (like "@tzres.dll,-211")

  // simply guess the name from the UTC bias of the timezone.

  // To properly resolve the resource identifier requires a library load,

  // which is not possible in a sandbox.

  if (std_tz_name_[0] == '\0' || std_tz_name_[0] == '@') {

    OS::SNPrintF(Vector<char>(std_tz_name_, kTzNameSize - 1),

                 "%s Standard Time",

                 GuessTimezoneNameFromBias(tzinfo_.Bias));

  }

  if (dst_tz_name_[0] == '\0' || dst_tz_name_[0] == '@') {

    OS::SNPrintF(Vector<char>(dst_tz_name_, kTzNameSize - 1),

                 "%s Daylight Time",

                 GuessTimezoneNameFromBias(tzinfo_.Bias));

  }

  // Timezone information initialized.

  tz_initialized_ = true;

}

// Return the local timezone offset in milliseconds east of UTC. This

// takes into account whether daylight saving is in effect at the time.

// Only times in the 32-bit Unix range may be passed to this function.

// Also, adding the time-zone offset to the input must not overflow.

// The function EquivalentTime() in date.js guarantees this.

int64_t Win32Time::LocalOffset() {

  // Initialize timezone information, if needed.

  TzSet();

  Win32Time rounded_to_second(*this);

  rounded_to_second.t() = rounded_to_second.t() / 1000 / kTimeScaler *

      1000 * kTimeScaler;

  // Convert to local time using POSIX localtime function.

  // Windows XP Service Pack 3 made SystemTimeToTzSpecificLocalTime()

  // very slow.  Other browsers use localtime().

  // Convert from JavaScript milliseconds past 1/1/1970 0:00:00 to

  // POSIX seconds past 1/1/1970 0:00:00.

  double unchecked_posix_time = rounded_to_second.ToJSTime() / 1000;

  if (unchecked_posix_time > INT_MAX || unchecked_posix_time < 0) {

    return 0;

  }

  // Because _USE_32BIT_TIME_T is defined, time_t is a 32-bit int.

  time_t posix_time = static_cast<time_t>(unchecked_posix_time);

  // Convert to local time, as struct with fields for day, hour, year, etc.

  tm posix_local_time_struct;

  if (localtime_s(&posix_local_time_struct, &posix_time)) return 0;

  if (posix_local_time_struct.tm_isdst > 0) {

    return (tzinfo_.Bias + tzinfo_.DaylightBias) * -kMsPerMinute;

  } else if (posix_local_time_struct.tm_isdst == 0) {

    return (tzinfo_.Bias + tzinfo_.StandardBias) * -kMsPerMinute;

  } else {

    return tzinfo_.Bias * -kMsPerMinute;

  }

}

// Return whether or not daylight savings time is in effect at this time.

bool Win32Time::InDST() {

  // Initialize timezone information, if needed.

  TzSet();

  // Determine if DST is in effect at the specified time.

  bool in_dst = false;

  if (tzinfo_.StandardDate.wMonth != 0 || tzinfo_.DaylightDate.wMonth != 0) {

    // Get the local timezone offset for the timestamp in milliseconds.

    int64_t offset = LocalOffset();

    // Compute the offset for DST. The bias parameters in the timezone info

    // are specified in minutes. These must be converted to milliseconds.

    int64_t dstofs = -(tzinfo_.Bias + tzinfo_.DaylightBias) * kMsPerMinute;

    // If the local time offset equals the timezone bias plus the daylight

    // bias then DST is in effect.

    in_dst = offset == dstofs;

  }

  return in_dst;

}

// Return the daylight savings time offset for this time.

int64_t Win32Time::DaylightSavingsOffset() {

  return InDST() ? 60 * kMsPerMinute : 0;

}

// Returns a string identifying the current timezone for the

// timestamp taking into account daylight saving.

char* Win32Time::LocalTimezone() {

  // Return the standard or DST time zone name based on whether daylight

  // saving is in effect at the given time.

  return InDST() ? dst_tz_name_ : std_tz_name_;

}

void OS::PostSetUp() {

  // Math functions depend on CPU features therefore they are initialized after

  // CPU.

  MathSetup();

#if V8_TARGET_ARCH_IA32

  OS::MemMoveFunction generated_memmove = CreateMemMoveFunction();

  if (generated_memmove != NULL) {

    memmove_function = generated_memmove;

  }

#endif

}

// Returns the accumulated user time for thread.

int OS::GetUserTime(uint32_t* secs,  uint32_t* usecs) {

  FILETIME dummy;

  uint64_t usertime;

  // Get the amount of time that the thread has executed in user mode.

  if (!GetThreadTimes(GetCurrentThread(), &dummy, &dummy, &dummy,

                      reinterpret_cast<FILETIME*>(&usertime))) return -1;

  // Adjust the resolution to micro-seconds.

  usertime /= 10;

  // Convert to seconds and microseconds

  *secs = static_cast<uint32_t>(usertime / 1000000);

  *usecs = static_cast<uint32_t>(usertime % 1000000);

  return 0;

}

// Returns current time as the number of milliseconds since

// 00:00:00 UTC, January 1, 1970.

double OS::TimeCurrentMillis() {

  return Time::Now().ToJsTime();

}

// Returns a string identifying the current timezone taking into

// account daylight saving.

const char* OS::LocalTimezone(double time) {

  return Win32Time(time).LocalTimezone();

}

// Returns the local time offset in milliseconds east of UTC without

// taking daylight savings time into account.

double OS::LocalTimeOffset() {

  // Use current time, rounded to the millisecond.

  Win32Time t(TimeCurrentMillis());

  // Time::LocalOffset inlcudes any daylight savings offset, so subtract it.

  return static_cast<double>(t.LocalOffset() - t.DaylightSavingsOffset());

}

// Returns the daylight savings offset in milliseconds for the given

// time.

double OS::DaylightSavingsOffset(double time) {

  int64_t offset = Win32Time(time).DaylightSavingsOffset();

  return static_cast<double>(offset);

}

int OS::GetLastError() {

  return ::GetLastError();

}

int OS::GetCurrentProcessId() {

  return static_cast<int>(::GetCurrentProcessId());

}

// ----------------------------------------------------------------------------

// Win32 console output.

//

// If a Win32 application is linked as a console application it has a normal

// standard output and standard error. In this case normal printf works fine

// for output. However, if the application is linked as a GUI application,

// the process doesn't have a console, and therefore (debugging) output is lost.

// This is the case if we are embedded in a windows program (like a browser).

// In order to be able to get debug output in this case the the debugging

// facility using OutputDebugString. This output goes to the active debugger

// for the process (if any). Else the output can be monitored using DBMON.EXE.

enum OutputMode {

  UNKNOWN,  // Output method has not yet been determined.

  CONSOLE,  // Output is written to stdout.

  ODS       // Output is written to debug facility.

};

static OutputMode output_mode = UNKNOWN;  // Current output mode.

// Determine if the process has a console for output.

static bool HasConsole() {

  // Only check the first time. Eventual race conditions are not a problem,

  // because all threads will eventually determine the same mode.

  if (output_mode == UNKNOWN) {

    // We cannot just check that the standard output is attached to a console

    // because this would fail if output is redirected to a file. Therefore we

    // say that a process does not have an output console if either the

    // standard output handle is invalid or its file type is unknown.

    if (GetStdHandle(STD_OUTPUT_HANDLE) != INVALID_HANDLE_VALUE &&

        GetFileType(GetStdHandle(STD_OUTPUT_HANDLE)) != FILE_TYPE_UNKNOWN)

      output_mode = CONSOLE;

    else

      output_mode = ODS;

  }

  return output_mode == CONSOLE;

}

static void VPrintHelper(FILE* stream, const char* format, va_list args) {

  if (HasConsole()) {

    vfprintf(stream, format, args);

  } else {

    // It is important to use safe print here in order to avoid

    // overflowing the buffer. We might truncate the output, but this

    // does not crash.

    EmbeddedVector<char, 4096> buffer;

    OS::VSNPrintF(buffer, format, args);

    OutputDebugStringA(buffer.start());

  }

}

FILE* OS::FOpen(const char* path, const char* mode) {

  FILE* result;

  if (fopen_s(&result, path, mode) == 0) {

    return result;

  } else {

    return NULL;

  }

}

bool OS::Remove(const char* path) {

  return (DeleteFileA(path) != 0);

}

FILE* OS::OpenTemporaryFile() {

  // tmpfile_s tries to use the root dir, don't use it.

  char tempPathBuffer[MAX_PATH];

  DWORD path_result = 0;

  path_result = GetTempPathA(MAX_PATH, tempPathBuffer);

  if (path_result > MAX_PATH || path_result == 0) return NULL;

  UINT name_result = 0;

  char tempNameBuffer[MAX_PATH];

  name_result = GetTempFileNameA(tempPathBuffer, "", 0, tempNameBuffer);

  if (name_result == 0) return NULL;

  FILE* result = FOpen(tempNameBuffer, "w+");  // Same mode as tmpfile uses.

  if (result != NULL) {

    Remove(tempNameBuffer);  // Delete on close.

  }

  return result;

}

// Open log file in binary mode to avoid /n -> /r/n conversion.

const char* const OS::LogFileOpenMode = "wb";

// Print (debug) message to console.

void OS::Print(const char* format, ...) {

  va_list args;

  va_start(args, format);

  VPrint(format, args);

  va_end(args);

}

void OS::VPrint(const char* format, va_list args) {

  VPrintHelper(stdout, format, args);

}

void OS::FPrint(FILE* out, const char* format, ...) {

  va_list args;

  va_start(args, format);

  VFPrint(out, format, args);

  va_end(args);

}

void OS::VFPrint(FILE* out, const char* format, va_list args) {

  VPrintHelper(out, format, args);

}

// Print error message to console.

void OS::PrintError(const char* format, ...) {

  va_list args;

  va_start(args, format);

  VPrintError(format, args);

  va_end(args);

}

void OS::VPrintError(const char* format, va_list args) {

  VPrintHelper(stderr, format, args);

}

int OS::SNPrintF(Vector<char> str, const char* format, ...) {

  va_list args;

  va_start(args, format);

  int result = VSNPrintF(str, format, args);

  va_end(args);

  return result;

}

int OS::VSNPrintF(Vector<char> str, const char* format, va_list args) {

  int n = _vsnprintf_s(str.start(), str.length(), _TRUNCATE, format, args);

  // Make sure to zero-terminate the string if the output was

  // truncated or if there was an error.

  if (n < 0 || n >= str.length()) {

    if (str.length() > 0)

      str[str.length() - 1] = '\0';

    return -1;

  } else {

    return n;

  }

}

char* OS::StrChr(char* str, int c) {

  return const_cast<char*>(strchr(str, c));

}

void OS::StrNCpy(Vector<char> dest, const char* src, size_t n) {

  // Use _TRUNCATE or strncpy_s crashes (by design) if buffer is too small.

  size_t buffer_size = static_cast<size_t>(dest.length());

  if (n + 1 > buffer_size)  // count for trailing '\0'

    n = _TRUNCATE;

  int result = strncpy_s(dest.start(), dest.length(), src, n);

  USE(result);

  ASSERT(result == 0 || (n == _TRUNCATE && result == STRUNCATE));

}

#undef _TRUNCATE

#undef STRUNCATE

// Get the system's page size used by VirtualAlloc() or the next power

// of two. The reason for always returning a power of two is that the

// rounding up in OS::Allocate expects that.

static size_t GetPageSize() {

  static size_t page_size = 0;

  if (page_size == 0) {

    SYSTEM_INFO info;

    GetSystemInfo(&info);

    page_size = RoundUpToPowerOf2(info.dwPageSize);

  }

  return page_size;

}

// The allocation alignment is the guaranteed alignment for

// VirtualAlloc'ed blocks of memory.

size_t OS::AllocateAlignment() {

  static size_t allocate_alignment = 0;

  if (allocate_alignment == 0) {

    SYSTEM_INFO info;

    GetSystemInfo(&info);

    allocate_alignment = info.dwAllocationGranularity;

  }

  return allocate_alignment;

}

void* OS::GetRandomMmapAddr() {

  Isolate* isolate = Isolate::UncheckedCurrent();

  // Note that the current isolate isn't set up in a call path via

  // CpuFeatures::Probe. We don't care about randomization in this case because

  // the code page is immediately freed.

  if (isolate != NULL) {

    // The address range used to randomize RWX allocations in OS::Allocate

    // Try not to map pages into the default range that windows loads DLLs

    // Use a multiple of 64k to prevent committing unused memory.

    // Note: This does not guarantee RWX regions will be within the

    // range kAllocationRandomAddressMin to kAllocationRandomAddressMax

#ifdef V8_HOST_ARCH_64_BIT

    static const intptr_t kAllocationRandomAddressMin = 0x0000000080000000;

    static const intptr_t kAllocationRandomAddressMax = 0x000003FFFFFF0000;

#else

    static const intptr_t kAllocationRandomAddressMin = 0x04000000;

    static const intptr_t kAllocationRandomAddressMax = 0x3FFF0000;

#endif

    uintptr_t address =

        (isolate->random_number_generator()->NextInt() << kPageSizeBits) |

        kAllocationRandomAddressMin;

    address &= kAllocationRandomAddressMax;

    return reinterpret_cast<void *>(address);

  }

  return NULL;

}

static void* RandomizedVirtualAlloc(size_t size, int action, int protection) {

  LPVOID base = NULL;

  if (protection == PAGE_EXECUTE_READWRITE || protection == PAGE_NOACCESS) {

    // For exectutable pages try and randomize the allocation address

    for (size_t attempts = 0; base == NULL && attempts < 3; ++attempts) {

      base = VirtualAlloc(OS::GetRandomMmapAddr(), size, action, protection);

    }

  }

  // After three attempts give up and let the OS find an address to use.

  if (base == NULL) base = VirtualAlloc(NULL, size, action, protection);

  return base;

}

void* OS::Allocate(const size_t requested,

                   size_t* allocated,

                   bool is_executable) {

  // VirtualAlloc rounds allocated size to page size automatically.

  size_t msize = RoundUp(requested, static_cast<int>(GetPageSize()));

  // Windows XP SP2 allows Data Excution Prevention (DEP).

  int prot = is_executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;

  LPVOID mbase = RandomizedVirtualAlloc(msize,

                                        MEM_COMMIT | MEM_RESERVE,

                                        prot);

  if (mbase == NULL) {

    LOG(Isolate::Current(), StringEvent("OS::Allocate", "VirtualAlloc failed"));

    return NULL;

  }

  ASSERT(IsAligned(reinterpret_cast<size_t>(mbase), OS::AllocateAlignment()));

  *allocated = msize;

  return mbase;

}

void OS::Free(void* address, const size_t size) {

  // TODO(1240712): VirtualFree has a return value which is ignored here.

  VirtualFree(address, 0, MEM_RELEASE);

  USE(size);

}

intptr_t OS::CommitPageSize() {

  return 4096;

}

void OS::ProtectCode(void* address, const size_t size) {

  DWORD old_protect;

  VirtualProtect(address, size, PAGE_EXECUTE_READ, &old_protect);

}

void OS::Guard(void* address, const size_t size) {

  DWORD oldprotect;

  VirtualProtect(address, size, PAGE_NOACCESS, &oldprotect);

}

void OS::Sleep(int milliseconds) {

  ::Sleep(milliseconds);

}

void OS::Abort() {

  if (IsDebuggerPresent() || FLAG_break_on_abort) {

    DebugBreak();

  } else {

    // Make the MSVCRT do a silent abort.

    raise(SIGABRT);

  }

}

void OS::DebugBreak() {

#ifdef _MSC_VER

  // To avoid Visual Studio runtime support the following code can be used

  // instead

  // __asm { int 3 }

  __debugbreak();

#else

  ::DebugBreak();

#endif

}

class Win32MemoryMappedFile : public OS::MemoryMappedFile {

 public:

  Win32MemoryMappedFile(HANDLE file,

                        HANDLE file_mapping,

                        void* memory,

                        int size)

      : file_(file),

        file_mapping_(file_mapping),

        memory_(memory),

        size_(size) { }

  virtual ~Win32MemoryMappedFile();

  virtual void* memory() { return memory_; }

  virtual int size() { return size_; }

 private:

  HANDLE file_;

  HANDLE file_mapping_;

  void* memory_;

  int size_;

};

OS::MemoryMappedFile* OS::MemoryMappedFile::open(const char* name) {

  // Open a physical file

  HANDLE file = CreateFileA(name, GENERIC_READ | GENERIC_WRITE,

      FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, NULL);

  if (file == INVALID_HANDLE_VALUE) return NULL;

  int size = static_cast<int>(GetFileSize(file, NULL));

  // Create a file mapping for the physical file

  HANDLE file_mapping = CreateFileMapping(file, NULL,

      PAGE_READWRITE, 0, static_cast<DWORD>(size), NULL);

  if (file_mapping == NULL) return NULL;

  // Map a view of the file into memory

  void* memory = MapViewOfFile(file_mapping, FILE_MAP_ALL_ACCESS, 0, 0, size);

  return new Win32MemoryMappedFile(file, file_mapping, memory, size);

}

OS::MemoryMappedFile* OS::MemoryMappedFile::create(const char* name, int size,

    void* initial) {

  // Open a physical file

  HANDLE file = CreateFileA(name, GENERIC_READ | GENERIC_WRITE,

      FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, 0, NULL);

  if (file == NULL) return NULL;

  // Create a file mapping for the physical file

  HANDLE file_mapping = CreateFileMapping(file, NULL,

      PAGE_READWRITE, 0, static_cast<DWORD>(size), NULL);

  if (file_mapping == NULL) return NULL;

  // Map a view of the file into memory

  void* memory = MapViewOfFile(file_mapping, FILE_MAP_ALL_ACCESS, 0, 0, size);

  if (memory) OS::MemMove(memory, initial, size);

  return new Win32MemoryMappedFile(file, file_mapping, memory, size);

}

Win32MemoryMappedFile::~Win32MemoryMappedFile() {

  if (memory_ != NULL)

    UnmapViewOfFile(memory_);

  CloseHandle(file_mapping_);

  CloseHandle(file_);

}

// The following code loads functions defined in DbhHelp.h and TlHelp32.h

// dynamically. This is to avoid being depending on dbghelp.dll and

// tlhelp32.dll when running (the functions in tlhelp32.dll have been moved to

// kernel32.dll at some point so loading functions defines in TlHelp32.h

// dynamically might not be necessary any more - for some versions of Windows?).

// Function pointers to functions dynamically loaded from dbghelp.dll.

#define DBGHELP_FUNCTION_LIST(V)  \

  V(SymInitialize)                \

  V(SymGetOptions)                \

  V(SymSetOptions)                \

  V(SymGetSearchPath)             \

  V(SymLoadModule64)              \

  V(StackWalk64)                  \

  V(SymGetSymFromAddr64)          \

  V(SymGetLineFromAddr64)         \

  V(SymFunctionTableAccess64)     \

  V(SymGetModuleBase64)

// Function pointers to functions dynamically loaded from dbghelp.dll.

#define TLHELP32_FUNCTION_LIST(V)  \

  V(CreateToolhelp32Snapshot)      \

  V(Module32FirstW)                \

  V(Module32NextW)

// Define the decoration to use for the type and variable name used for

// dynamically loaded DLL function..

#define DLL_FUNC_TYPE(name) _##name##_

#define DLL_FUNC_VAR(name) _##name

// Define the type for each dynamically loaded DLL function. The function

// definitions are copied from DbgHelp.h and TlHelp32.h. The IN and VOID macros

// from the Windows include files are redefined here to have the function

// definitions to be as close to the ones in the original .h files as possible.

#ifndef IN

#define IN

#endif

#ifndef VOID

#define VOID void

#endif

// DbgHelp isn't supported on MinGW yet

#ifndef __MINGW32__

// DbgHelp.h functions.

typedef BOOL (__stdcall *DLL_FUNC_TYPE(SymInitialize))(IN HANDLE hProcess,

                                                       IN PSTR UserSearchPath,

                                                       IN BOOL fInvadeProcess);

typedef DWORD (__stdcall *DLL_FUNC_TYPE(SymGetOptions))(VOID);

typedef DWORD (__stdcall *DLL_FUNC_TYPE(SymSetOptions))(IN DWORD SymOptions);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(SymGetSearchPath))(

    IN HANDLE hProcess,

    OUT PSTR SearchPath,

    IN DWORD SearchPathLength);

typedef DWORD64 (__stdcall *DLL_FUNC_TYPE(SymLoadModule64))(

    IN HANDLE hProcess,

    IN HANDLE hFile,

    IN PSTR ImageName,

    IN PSTR ModuleName,

    IN DWORD64 BaseOfDll,

    IN DWORD SizeOfDll);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(StackWalk64))(

    DWORD MachineType,

    HANDLE hProcess,

    HANDLE hThread,

    LPSTACKFRAME64 StackFrame,

    PVOID ContextRecord,

    PREAD_PROCESS_MEMORY_ROUTINE64 ReadMemoryRoutine,

    PFUNCTION_TABLE_ACCESS_ROUTINE64 FunctionTableAccessRoutine,

    PGET_MODULE_BASE_ROUTINE64 GetModuleBaseRoutine,

    PTRANSLATE_ADDRESS_ROUTINE64 TranslateAddress);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(SymGetSymFromAddr64))(

    IN HANDLE hProcess,

    IN DWORD64 qwAddr,

    OUT PDWORD64 pdwDisplacement,

    OUT PIMAGEHLP_SYMBOL64 Symbol);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(SymGetLineFromAddr64))(

    IN HANDLE hProcess,

    IN DWORD64 qwAddr,

    OUT PDWORD pdwDisplacement,

    OUT PIMAGEHLP_LINE64 Line64);

// DbgHelp.h typedefs. Implementation found in dbghelp.dll.

typedef PVOID (__stdcall *DLL_FUNC_TYPE(SymFunctionTableAccess64))(

    HANDLE hProcess,

    DWORD64 AddrBase);  // DbgHelp.h typedef PFUNCTION_TABLE_ACCESS_ROUTINE64

typedef DWORD64 (__stdcall *DLL_FUNC_TYPE(SymGetModuleBase64))(

    HANDLE hProcess,

    DWORD64 AddrBase);  // DbgHelp.h typedef PGET_MODULE_BASE_ROUTINE64

// TlHelp32.h functions.

typedef HANDLE (__stdcall *DLL_FUNC_TYPE(CreateToolhelp32Snapshot))(

    DWORD dwFlags,

    DWORD th32ProcessID);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(Module32FirstW))(HANDLE hSnapshot,

                                                        LPMODULEENTRY32W lpme);

typedef BOOL (__stdcall *DLL_FUNC_TYPE(Module32NextW))(HANDLE hSnapshot,

                                                       LPMODULEENTRY32W lpme);

#undef IN

#undef VOID

// Declare a variable for each dynamically loaded DLL function.

#define DEF_DLL_FUNCTION(name) DLL_FUNC_TYPE(name) DLL_FUNC_VAR(name) = NULL;

DBGHELP_FUNCTION_LIST(DEF_DLL_FUNCTION)

TLHELP32_FUNCTION_LIST(DEF_DLL_FUNCTION)

#undef DEF_DLL_FUNCTION

// Load the functions. This function has a lot of "ugly" macros in order to

// keep down code duplication.

static bool LoadDbgHelpAndTlHelp32() {

  static bool dbghelp_loaded = false;

  if (dbghelp_loaded) return true;

  HMODULE module;

  // Load functions from the dbghelp.dll module.

  module = LoadLibrary(TEXT("dbghelp.dll"));

  if (module == NULL) {

    return false;

  }

#define LOAD_DLL_FUNC(name)                                                 \

  DLL_FUNC_VAR(name) =                                                      \

      reinterpret_cast<DLL_FUNC_TYPE(name)>(GetProcAddress(module, #name));

DBGHELP_FUNCTION_LIST(LOAD_DLL_FUNC)

#undef LOAD_DLL_FUNC

  // Load functions from the kernel32.dll module (the TlHelp32.h function used

  // to be in tlhelp32.dll but are now moved to kernel32.dll).

  module = LoadLibrary(TEXT("kernel32.dll"));

  if (module == NULL) {

    return false;

  }

#define LOAD_DLL_FUNC(name)                                                 \

  DLL_FUNC_VAR(name) =                                                      \

      reinterpret_cast<DLL_FUNC_TYPE(name)>(GetProcAddress(module, #name));

TLHELP32_FUNCTION_LIST(LOAD_DLL_FUNC)

#undef LOAD_DLL_FUNC

  // Check that all functions where loaded.

  bool result =

#define DLL_FUNC_LOADED(name) (DLL_FUNC_VAR(name) != NULL) &&

DBGHELP_FUNCTION_LIST(DLL_FUNC_LOADED)

TLHELP32_FUNCTION_LIST(DLL_FUNC_LOADED)

#undef DLL_FUNC_LOADED

  true;

  dbghelp_loaded = result;

  return result;

  // NOTE: The modules are never unloaded and will stay around until the

  // application is closed.

}

#undef DBGHELP_FUNCTION_LIST

#undef TLHELP32_FUNCTION_LIST

#undef DLL_FUNC_VAR

#undef DLL_FUNC_TYPE

// Load the symbols for generating stack traces.

static bool LoadSymbols(Isolate* isolate, HANDLE process_handle) {

  static bool symbols_loaded = false;

  if (symbols_loaded) return true;

  BOOL ok;

  // Initialize the symbol engine.

  ok = _SymInitialize(process_handle,  // hProcess

                      NULL,            // UserSearchPath

                      false);          // fInvadeProcess

  if (!ok) return false;

  DWORD options = _SymGetOptions();

  options |= SYMOPT_LOAD_LINES;

  options |= SYMOPT_FAIL_CRITICAL_ERRORS;

  options = _SymSetOptions(options);

  char buf[OS::kStackWalkMaxNameLen] = {0};

  ok = _SymGetSearchPath(process_handle, buf, OS::kStackWalkMaxNameLen);

  if (!ok) {

    int err = GetLastError();

    PrintF("%d\n", err);

    return false;

  }

  HANDLE snapshot = _CreateToolhelp32Snapshot(

      TH32CS_SNAPMODULE,       // dwFlags

      GetCurrentProcessId());  // th32ProcessId

  if (snapshot == INVALID_HANDLE_VALUE) return false;

  MODULEENTRY32W module_entry;

  module_entry.dwSize = sizeof(module_entry);  // Set the size of the structure.

  BOOL cont = _Module32FirstW(snapshot, &module_entry);

  while (cont) {

    DWORD64 base;

    // NOTE the SymLoadModule64 function has the peculiarity of accepting a

    // both unicode and ASCII strings even though the parameter is PSTR.

    base = _SymLoadModule64(

        process_handle,                                       // hProcess

        0,                                                    // hFile

        reinterpret_cast<PSTR>(module_entry.szExePath),       // ImageName

        reinterpret_cast<PSTR>(module_entry.szModule),        // ModuleName

        reinterpret_cast<DWORD64>(module_entry.modBaseAddr),  // BaseOfDll

        module_entry.modBaseSize);                            // SizeOfDll

    if (base == 0) {

      int err = GetLastError();

      if (err != ERROR_MOD_NOT_FOUND &&

          err != ERROR_INVALID_HANDLE) return false;

    }

    LOG(isolate,

        SharedLibraryEvent(

            module_entry.szExePath,

            reinterpret_cast<unsigned int>(module_entry.modBaseAddr),

            reinterpret_cast<unsigned int>(module_entry.modBaseAddr +

                                           module_entry.modBaseSize)));

    cont = _Module32NextW(snapshot, &module_entry);

  }

  CloseHandle(snapshot);

  symbols_loaded = true;

  return true;

}

void OS::LogSharedLibraryAddresses(Isolate* isolate) {

  // SharedLibraryEvents are logged when loading symbol information.

  // Only the shared libraries loaded at the time of the call to

  // LogSharedLibraryAddresses are logged.  DLLs loaded after

  // initialization are not accounted for.

  if (!LoadDbgHelpAndTlHelp32()) return;

  HANDLE process_handle = GetCurrentProcess();

  LoadSymbols(isolate, process_handle);

}

void OS::SignalCodeMovingGC() {

}

uint64_t OS::TotalPhysicalMemory() {

  MEMORYSTATUSEX memory_info;

  memory_info.dwLength = sizeof(memory_info);

  if (!GlobalMemoryStatusEx(&memory_info)) {

    UNREACHABLE();

    return 0;

  }

  return static_cast<uint64_t>(memory_info.ullTotalPhys);

}

#else  // __MINGW32__

void OS::LogSharedLibraryAddresses(Isolate* isolate) { }

void OS::SignalCodeMovingGC() { }

#endif  // __MINGW32__

uint64_t OS::CpuFeaturesImpliedByPlatform() {

  return 0;  // Windows runs on anything.

}

double OS::nan_value() {

#ifdef _MSC_VER

  // Positive Quiet NaN with no payload (aka. Indeterminate) has all bits

  // in mask set, so value equals mask.

  static const __int64 nanval = kQuietNaNMask;

  return *reinterpret_cast<const double*>(&nanval);

#else  // _MSC_VER

  return NAN;

#endif  // _MSC_VER

}

int OS::ActivationFrameAlignment() {

#ifdef _WIN64

  return 16;  // Windows 64-bit ABI requires the stack to be 16-byte aligned.

#elif defined(__MINGW32__)

  // With gcc 4.4 the tree vectorization optimizer can generate code

  // that requires 16 byte alignment such as movdqa on x86.

  return 16;

#else

  return 8;  // Floating-point math runs faster with 8-byte alignment.

#endif

}

VirtualMemory::VirtualMemory() : address_(NULL), size_(0) { }

VirtualMemory::VirtualMemory(size_t size)

    : address_(ReserveRegion(size)), size_(size) { }

VirtualMemory::VirtualMemory(size_t size, size_t alignment)

    : address_(NULL), size_(0) {

  ASSERT(IsAligned(alignment, static_cast<intptr_t>(OS::AllocateAlignment())));

  size_t request_size = RoundUp(size + alignment,

                                static_cast<intptr_t>(OS::AllocateAlignment()));

  void* address = ReserveRegion(request_size);

  if (address == NULL) return;

  Address base = RoundUp(static_cast<Address>(address), alignment);

  // Try reducing the size by freeing and then reallocating a specific area.

  bool result = ReleaseRegion(address, request_size);