Process.cpp revision 280031 
1//===-- Process.cpp - Implement OS Process Concept --------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements the operating system Process concept.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/ADT/StringExtras.h"
15#include "llvm/Config/config.h"
16#include "llvm/Support/ErrorHandling.h"
17#include "llvm/Support/FileSystem.h"
18#include "llvm/Support/Process.h"
19#include "llvm/Support/Program.h"
20
21using namespace llvm;
22using namespace sys;
23
24//===----------------------------------------------------------------------===//
25//=== WARNING: Implementation here must contain only TRULY operating system
26//===          independent code.
27//===----------------------------------------------------------------------===//
28
29/// \brief A helper function to compute the elapsed wall-time since the program
30/// started.
31///
32/// Note that this routine actually computes the elapsed wall time since the
33/// first time it was called. However, we arrange to have it called during the
34/// startup of the process to get approximately correct results.
35static TimeValue getElapsedWallTime() {
36  static TimeValue &StartTime = *new TimeValue(TimeValue::now());
37  return TimeValue::now() - StartTime;
38}
39
40/// \brief A special global variable to ensure we call \c getElapsedWallTime
41/// during global initialization of the program.
42///
43/// Note that this variable is never referenced elsewhere. Doing so could
44/// create race conditions during program startup or shutdown.
45static volatile TimeValue DummyTimeValue = getElapsedWallTime();
46
47Optional<std::string> Process::FindInEnvPath(const std::string& EnvName,
48                                             const std::string& FileName)
49{
50  Optional<std::string> FoundPath;
51  Optional<std::string> OptPath = Process::GetEnv(EnvName);
52  if (!OptPath.hasValue())
53    return FoundPath;
54
55  const char EnvPathSeparatorStr[] = {EnvPathSeparator, '\0'};
56  SmallVector<StringRef, 8> Dirs;
57  SplitString(OptPath.getValue(), Dirs, EnvPathSeparatorStr);
58
59  for (const auto &Dir : Dirs) {
60    if (Dir.empty())
61      continue;
62
63    SmallString<128> FilePath(Dir);
64    path::append(FilePath, FileName);
65    if (fs::exists(Twine(FilePath))) {
66      FoundPath = FilePath.str();
67      break;
68    }
69  }
70
71  return FoundPath;
72}
73
74
75#define COLOR(FGBG, CODE, BOLD) "\033[0;" BOLD FGBG CODE "m"
76
77#define ALLCOLORS(FGBG,BOLD) {\
78    COLOR(FGBG, "0", BOLD),\
79    COLOR(FGBG, "1", BOLD),\
80    COLOR(FGBG, "2", BOLD),\
81    COLOR(FGBG, "3", BOLD),\
82    COLOR(FGBG, "4", BOLD),\
83    COLOR(FGBG, "5", BOLD),\
84    COLOR(FGBG, "6", BOLD),\
85    COLOR(FGBG, "7", BOLD)\
86  }
87
88static const char colorcodes[2][2][8][10] = {
89 { ALLCOLORS("3",""), ALLCOLORS("3","1;") },
90 { ALLCOLORS("4",""), ALLCOLORS("4","1;") }
91};
92
93// Include the platform-specific parts of this class.
94#ifdef LLVM_ON_UNIX
95#include "Unix/Process.inc"
96#endif
97#ifdef LLVM_ON_WIN32
98#include "Windows/Process.inc"
99#endif
100