llvm-project/llvm/lib/Support/Process.cpp

125 lines
3.9 KiB
C++

//===-- 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())
continue;
SmallString<128> FilePath(Dir);
path::append(FilePath, FileName);
if (fs::exists(Twine(FilePath))) {
FoundPath = FilePath.str();
break;
}
}
return FoundPath;
}
#define COLOR(FGBG, CODE, BOLD) "\033[0;" BOLD FGBG CODE "m"
#define ALLCOLORS(FGBG,BOLD) {\
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.
#ifdef LLVM_ON_UNIX
#include "Unix/Process.inc"
#endif
#ifdef LLVM_ON_WIN32
#include "Windows/Process.inc"
#endif