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//===-- Process.cpp - Implement OS Process Concept --------------*- C++ -*-===//
//                     The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//  This file implements the operating system Process concept.

#include "llvm/ADT/StringExtras.h"
#include "llvm/Config/config.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Process.h"
#include "llvm/Support/Program.h"

using namespace llvm;
using namespace sys;

//=== WARNING: Implementation here must contain only TRULY operating system
//===          independent code.

// Empty virtual destructor to anchor the vtable for the process class.
process::~process() {}

self_process *process::get_self() {
  // Use a function local static for thread safe initialization and allocate it
  // as a raw pointer to ensure it is never destroyed.
  static self_process *SP = new self_process();

  return SP;

// The destructor for the self_process subclass must never actually be
// executed. There should be at most one instance of this class, and that
// instance should live until the process terminates to avoid the potential for
// racy accesses during shutdown.
self_process::~self_process() {
  llvm_unreachable("This destructor must never be executed!");

/// \brief A helper function to compute the elapsed wall-time since the program
/// started.
/// Note that this routine actually computes the elapsed wall time since the
/// first time it was called. However, we arrange to have it called during the
/// startup of the process to get approximately correct results.
static TimeValue getElapsedWallTime() {
  static TimeValue &StartTime = *new TimeValue(TimeValue::now());
  return TimeValue::now() - StartTime;

/// \brief A special global variable to ensure we call \c getElapsedWallTime
/// during global initialization of the program.
/// Note that this variable is never referenced elsewhere. Doing so could
/// create race conditions during program startup or shutdown.
static volatile TimeValue DummyTimeValue = getElapsedWallTime();

// Implement this routine by using the static helpers above. They're already
// portable.
TimeValue self_process::get_wall_time() const {
  return getElapsedWallTime();

Optional<std::string> Process::FindInEnvPath(const std::string& EnvName,
                                             const std::string& FileName)
  Optional<std::string> FoundPath;
  Optional<std::string> OptPath = Process::GetEnv(EnvName);
  if (!OptPath.hasValue())
    return FoundPath;

  const char EnvPathSeparatorStr[] = {EnvPathSeparator, '\0'};
  SmallVector<StringRef, 8> Dirs;
  SplitString(OptPath.getValue(), Dirs, EnvPathSeparatorStr);

  for (const auto &Dir : Dirs) {
    if (Dir.empty())

    SmallString<128> FilePath(Dir);
    path::append(FilePath, FileName);
    if (fs::exists(Twine(FilePath))) {
      FoundPath = FilePath.str();

  return FoundPath;

#define COLOR(FGBG, CODE, BOLD) "\033[0;" BOLD FGBG CODE "m"

    COLOR(FGBG, "0", BOLD),\
    COLOR(FGBG, "1", BOLD),\
    COLOR(FGBG, "2", BOLD),\
    COLOR(FGBG, "3", BOLD),\
    COLOR(FGBG, "4", BOLD),\
    COLOR(FGBG, "5", BOLD),\
    COLOR(FGBG, "6", BOLD),\
    COLOR(FGBG, "7", BOLD)\

static const char colorcodes[2][2][8][10] = {
 { ALLCOLORS("3",""), ALLCOLORS("3","1;") },
 { ALLCOLORS("4",""), ALLCOLORS("4","1;") }

// Include the platform-specific parts of this class.
#include "Unix/Process.inc"
#ifdef LLVM_ON_WIN32
#include "Windows/Process.inc"