diff options
Diffstat (limited to 'contrib/llvm/lib/Support/Unix/Program.inc')
| -rw-r--r-- | contrib/llvm/lib/Support/Unix/Program.inc | 469 | 
1 files changed, 469 insertions, 0 deletions
| diff --git a/contrib/llvm/lib/Support/Unix/Program.inc b/contrib/llvm/lib/Support/Unix/Program.inc new file mode 100644 index 000000000000..a8d1fe3c07d0 --- /dev/null +++ b/contrib/llvm/lib/Support/Unix/Program.inc @@ -0,0 +1,469 @@ +//===- llvm/Support/Unix/Program.cpp -----------------------------*- 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 Unix specific portion of the Program class. +// +//===----------------------------------------------------------------------===// + +//===----------------------------------------------------------------------===// +//=== WARNING: Implementation here must contain only generic UNIX code that +//===          is guaranteed to work on *all* UNIX variants. +//===----------------------------------------------------------------------===// + +#include "Unix.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/Config/config.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Errc.h" +#include "llvm/Support/FileSystem.h" +#include "llvm/Support/Path.h" +#include "llvm/Support/raw_ostream.h" +#if HAVE_SYS_STAT_H +#include <sys/stat.h> +#endif +#if HAVE_SYS_RESOURCE_H +#include <sys/resource.h> +#endif +#if HAVE_SIGNAL_H +#include <signal.h> +#endif +#if HAVE_FCNTL_H +#include <fcntl.h> +#endif +#if HAVE_UNISTD_H +#include <unistd.h> +#endif +#ifdef HAVE_POSIX_SPAWN +#ifdef __sun__ +#define  _RESTRICT_KYWD +#endif +#include <spawn.h> + +#if defined(__APPLE__) +#include <TargetConditionals.h> +#endif + +#if defined(__APPLE__) && !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) +#define USE_NSGETENVIRON 1 +#else +#define USE_NSGETENVIRON 0 +#endif + +#if !USE_NSGETENVIRON +  extern char **environ; +#else +#include <crt_externs.h> // _NSGetEnviron +#endif +#endif + +namespace llvm { + +using namespace sys; + +ProcessInfo::ProcessInfo() : Pid(0), ReturnCode(0) {} + +ErrorOr<std::string> sys::findProgramByName(StringRef Name, +                                            ArrayRef<StringRef> Paths) { +  assert(!Name.empty() && "Must have a name!"); +  // Use the given path verbatim if it contains any slashes; this matches +  // the behavior of sh(1) and friends. +  if (Name.find('/') != StringRef::npos) +    return std::string(Name); + +  SmallVector<StringRef, 16> EnvironmentPaths; +  if (Paths.empty()) +    if (const char *PathEnv = std::getenv("PATH")) { +      SplitString(PathEnv, EnvironmentPaths, ":"); +      Paths = EnvironmentPaths; +    } + +  for (auto Path : Paths) { +    if (Path.empty()) +      continue; + +    // Check to see if this first directory contains the executable... +    SmallString<128> FilePath(Path); +    sys::path::append(FilePath, Name); +    if (sys::fs::can_execute(FilePath.c_str())) +      return std::string(FilePath.str()); // Found the executable! +  } +  return errc::no_such_file_or_directory; +} + +static bool RedirectIO(const StringRef *Path, int FD, std::string* ErrMsg) { +  if (!Path) // Noop +    return false; +  std::string File; +  if (Path->empty()) +    // Redirect empty paths to /dev/null +    File = "/dev/null"; +  else +    File = *Path; + +  // Open the file +  int InFD = open(File.c_str(), FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666); +  if (InFD == -1) { +    MakeErrMsg(ErrMsg, "Cannot open file '" + File + "' for " +              + (FD == 0 ? "input" : "output")); +    return true; +  } + +  // Install it as the requested FD +  if (dup2(InFD, FD) == -1) { +    MakeErrMsg(ErrMsg, "Cannot dup2"); +    close(InFD); +    return true; +  } +  close(InFD);      // Close the original FD +  return false; +} + +#ifdef HAVE_POSIX_SPAWN +static bool RedirectIO_PS(const std::string *Path, int FD, std::string *ErrMsg, +                          posix_spawn_file_actions_t *FileActions) { +  if (!Path) // Noop +    return false; +  const char *File; +  if (Path->empty()) +    // Redirect empty paths to /dev/null +    File = "/dev/null"; +  else +    File = Path->c_str(); + +  if (int Err = posix_spawn_file_actions_addopen( +          FileActions, FD, File, +          FD == 0 ? O_RDONLY : O_WRONLY | O_CREAT, 0666)) +    return MakeErrMsg(ErrMsg, "Cannot dup2", Err); +  return false; +} +#endif + +static void TimeOutHandler(int Sig) { +} + +static void SetMemoryLimits (unsigned size) +{ +#if HAVE_SYS_RESOURCE_H && HAVE_GETRLIMIT && HAVE_SETRLIMIT +  struct rlimit r; +  __typeof__ (r.rlim_cur) limit = (__typeof__ (r.rlim_cur)) (size) * 1048576; + +  // Heap size +  getrlimit (RLIMIT_DATA, &r); +  r.rlim_cur = limit; +  setrlimit (RLIMIT_DATA, &r); +#ifdef RLIMIT_RSS +  // Resident set size. +  getrlimit (RLIMIT_RSS, &r); +  r.rlim_cur = limit; +  setrlimit (RLIMIT_RSS, &r); +#endif +#ifdef RLIMIT_AS  // e.g. NetBSD doesn't have it. +  // Don't set virtual memory limit if built with any Sanitizer. They need 80Tb +  // of virtual memory for shadow memory mapping. +#if !LLVM_MEMORY_SANITIZER_BUILD && !LLVM_ADDRESS_SANITIZER_BUILD +  // Virtual memory. +  getrlimit (RLIMIT_AS, &r); +  r.rlim_cur = limit; +  setrlimit (RLIMIT_AS, &r); +#endif +#endif +#endif +} + +} + +static bool Execute(ProcessInfo &PI, StringRef Program, const char **args, +                    const char **envp, const StringRef **redirects, +                    unsigned memoryLimit, std::string *ErrMsg) { +  if (!llvm::sys::fs::exists(Program)) { +    if (ErrMsg) +      *ErrMsg = std::string("Executable \"") + Program.str() + +                std::string("\" doesn't exist!"); +    return false; +  } + +  // If this OS has posix_spawn and there is no memory limit being implied, use +  // posix_spawn.  It is more efficient than fork/exec. +#ifdef HAVE_POSIX_SPAWN +  if (memoryLimit == 0) { +    posix_spawn_file_actions_t FileActionsStore; +    posix_spawn_file_actions_t *FileActions = nullptr; + +    // If we call posix_spawn_file_actions_addopen we have to make sure the +    // c strings we pass to it stay alive until the call to posix_spawn, +    // so we copy any StringRefs into this variable. +    std::string RedirectsStorage[3]; + +    if (redirects) { +      std::string *RedirectsStr[3] = {nullptr, nullptr, nullptr}; +      for (int I = 0; I < 3; ++I) { +        if (redirects[I]) { +          RedirectsStorage[I] = *redirects[I]; +          RedirectsStr[I] = &RedirectsStorage[I]; +        } +      } + +      FileActions = &FileActionsStore; +      posix_spawn_file_actions_init(FileActions); + +      // Redirect stdin/stdout. +      if (RedirectIO_PS(RedirectsStr[0], 0, ErrMsg, FileActions) || +          RedirectIO_PS(RedirectsStr[1], 1, ErrMsg, FileActions)) +        return false; +      if (redirects[1] == nullptr || redirects[2] == nullptr || +          *redirects[1] != *redirects[2]) { +        // Just redirect stderr +        if (RedirectIO_PS(RedirectsStr[2], 2, ErrMsg, FileActions)) +          return false; +      } else { +        // If stdout and stderr should go to the same place, redirect stderr +        // to the FD already open for stdout. +        if (int Err = posix_spawn_file_actions_adddup2(FileActions, 1, 2)) +          return !MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout", Err); +      } +    } + +    if (!envp) +#if !USE_NSGETENVIRON +      envp = const_cast<const char **>(environ); +#else +      // environ is missing in dylibs. +      envp = const_cast<const char **>(*_NSGetEnviron()); +#endif + +    // Explicitly initialized to prevent what appears to be a valgrind false +    // positive. +    pid_t PID = 0; +    int Err = posix_spawn(&PID, Program.str().c_str(), FileActions, +                          /*attrp*/nullptr, const_cast<char **>(args), +                          const_cast<char **>(envp)); + +    if (FileActions) +      posix_spawn_file_actions_destroy(FileActions); + +    if (Err) +     return !MakeErrMsg(ErrMsg, "posix_spawn failed", Err); + +    PI.Pid = PID; + +    return true; +  } +#endif + +  // Create a child process. +  int child = fork(); +  switch (child) { +    // An error occurred:  Return to the caller. +    case -1: +      MakeErrMsg(ErrMsg, "Couldn't fork"); +      return false; + +    // Child process: Execute the program. +    case 0: { +      // Redirect file descriptors... +      if (redirects) { +        // Redirect stdin +        if (RedirectIO(redirects[0], 0, ErrMsg)) { return false; } +        // Redirect stdout +        if (RedirectIO(redirects[1], 1, ErrMsg)) { return false; } +        if (redirects[1] && redirects[2] && +            *(redirects[1]) == *(redirects[2])) { +          // If stdout and stderr should go to the same place, redirect stderr +          // to the FD already open for stdout. +          if (-1 == dup2(1,2)) { +            MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout"); +            return false; +          } +        } else { +          // Just redirect stderr +          if (RedirectIO(redirects[2], 2, ErrMsg)) { return false; } +        } +      } + +      // Set memory limits +      if (memoryLimit!=0) { +        SetMemoryLimits(memoryLimit); +      } + +      // Execute! +      std::string PathStr = Program; +      if (envp != nullptr) +        execve(PathStr.c_str(), +               const_cast<char **>(args), +               const_cast<char **>(envp)); +      else +        execv(PathStr.c_str(), +              const_cast<char **>(args)); +      // If the execve() failed, we should exit. Follow Unix protocol and +      // return 127 if the executable was not found, and 126 otherwise. +      // Use _exit rather than exit so that atexit functions and static +      // object destructors cloned from the parent process aren't +      // redundantly run, and so that any data buffered in stdio buffers +      // cloned from the parent aren't redundantly written out. +      _exit(errno == ENOENT ? 127 : 126); +    } + +    // Parent process: Break out of the switch to do our processing. +    default: +      break; +  } + +  PI.Pid = child; + +  return true; +} + +namespace llvm { + +ProcessInfo sys::Wait(const ProcessInfo &PI, unsigned SecondsToWait, +                      bool WaitUntilTerminates, std::string *ErrMsg) { +  struct sigaction Act, Old; +  assert(PI.Pid && "invalid pid to wait on, process not started?"); + +  int WaitPidOptions = 0; +  pid_t ChildPid = PI.Pid; +  if (WaitUntilTerminates) { +    SecondsToWait = 0; +  } else if (SecondsToWait) { +    // Install a timeout handler.  The handler itself does nothing, but the +    // simple fact of having a handler at all causes the wait below to return +    // with EINTR, unlike if we used SIG_IGN. +    memset(&Act, 0, sizeof(Act)); +    Act.sa_handler = TimeOutHandler; +    sigemptyset(&Act.sa_mask); +    sigaction(SIGALRM, &Act, &Old); +    alarm(SecondsToWait); +  } else if (SecondsToWait == 0) +    WaitPidOptions = WNOHANG; + +  // Parent process: Wait for the child process to terminate. +  int status; +  ProcessInfo WaitResult; + +  do { +    WaitResult.Pid = waitpid(ChildPid, &status, WaitPidOptions); +  } while (WaitUntilTerminates && WaitResult.Pid == -1 && errno == EINTR); + +  if (WaitResult.Pid != PI.Pid) { +    if (WaitResult.Pid == 0) { +      // Non-blocking wait. +      return WaitResult; +    } else { +      if (SecondsToWait && errno == EINTR) { +        // Kill the child. +        kill(PI.Pid, SIGKILL); + +        // Turn off the alarm and restore the signal handler +        alarm(0); +        sigaction(SIGALRM, &Old, nullptr); + +        // Wait for child to die +        if (wait(&status) != ChildPid) +          MakeErrMsg(ErrMsg, "Child timed out but wouldn't die"); +        else +          MakeErrMsg(ErrMsg, "Child timed out", 0); + +        WaitResult.ReturnCode = -2; // Timeout detected +        return WaitResult; +      } else if (errno != EINTR) { +        MakeErrMsg(ErrMsg, "Error waiting for child process"); +        WaitResult.ReturnCode = -1; +        return WaitResult; +      } +    } +  } + +  // We exited normally without timeout, so turn off the timer. +  if (SecondsToWait && !WaitUntilTerminates) { +    alarm(0); +    sigaction(SIGALRM, &Old, nullptr); +  } + +  // Return the proper exit status. Detect error conditions +  // so we can return -1 for them and set ErrMsg informatively. +  int result = 0; +  if (WIFEXITED(status)) { +    result = WEXITSTATUS(status); +    WaitResult.ReturnCode = result; + +    if (result == 127) { +      if (ErrMsg) +        *ErrMsg = llvm::sys::StrError(ENOENT); +      WaitResult.ReturnCode = -1; +      return WaitResult; +    } +    if (result == 126) { +      if (ErrMsg) +        *ErrMsg = "Program could not be executed"; +      WaitResult.ReturnCode = -1; +      return WaitResult; +    } +  } else if (WIFSIGNALED(status)) { +    if (ErrMsg) { +      *ErrMsg = strsignal(WTERMSIG(status)); +#ifdef WCOREDUMP +      if (WCOREDUMP(status)) +        *ErrMsg += " (core dumped)"; +#endif +    } +    // Return a special value to indicate that the process received an unhandled +    // signal during execution as opposed to failing to execute. +    WaitResult.ReturnCode = -2; +  } +  return WaitResult; +} + +  std::error_code sys::ChangeStdinToBinary(){ +  // Do nothing, as Unix doesn't differentiate between text and binary. +    return std::error_code(); +} + +  std::error_code sys::ChangeStdoutToBinary(){ +  // Do nothing, as Unix doesn't differentiate between text and binary. +    return std::error_code(); +} + +std::error_code +llvm::sys::writeFileWithEncoding(StringRef FileName, StringRef Contents, +                                 WindowsEncodingMethod Encoding /*unused*/) { +  std::error_code EC; +  llvm::raw_fd_ostream OS(FileName, EC, llvm::sys::fs::OpenFlags::F_Text); + +  if (EC) +    return EC; + +  OS << Contents; + +  if (OS.has_error()) +    return make_error_code(errc::io_error); + +  return EC; +} + +bool llvm::sys::argumentsFitWithinSystemLimits(ArrayRef<const char*> Args) { +  static long ArgMax = sysconf(_SC_ARG_MAX); + +  // System says no practical limit. +  if (ArgMax == -1) +    return true; + +  // Conservatively account for space required by environment variables. +  long HalfArgMax = ArgMax / 2; + +  size_t ArgLength = 0; +  for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end(); +       I != E; ++I) { +    ArgLength += strlen(*I) + 1; +    if (ArgLength > size_t(HalfArgMax)) { +      return false; +    } +  } +  return true; +} +} | 
