Merge System into Support.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120298 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 422 insertions, 0 deletions

diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc
new file mode 100644
index 0000000000..e06f80ba83
--- /dev/null
+++ b/lib/Support/Unix/Program.inc
@@ -0,0 +1,422 @@
+//===- llvm/System/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 <llvm/Config/config.h>
+#include "Unix.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
+#ifdef HAVE_POSIX_SPAWN
+#include <spawn.h>
+#if !defined(__APPLE__)
+  extern char **environ;
+#else
+#include <crt_externs.h> // _NSGetEnviron
+#endif
+#endif
+
+namespace llvm {
+using namespace sys;
+
+Program::Program() : Data_(0) {}
+
+Program::~Program() {}
+
+unsigned Program::GetPid() const {
+  uint64_t pid = reinterpret_cast<uint64_t>(Data_);
+  return static_cast<unsigned>(pid);
+}
+
+// This function just uses the PATH environment variable to find the program.
+Path
+Program::FindProgramByName(const std::string& progName) {
+
+  // Check some degenerate cases
+  if (progName.length() == 0) // no program
+    return Path();
+  Path temp;
+  if (!temp.set(progName)) // invalid name
+    return Path();
+  // Use the given path verbatim if it contains any slashes; this matches
+  // the behavior of sh(1) and friends.
+  if (progName.find('/') != std::string::npos)
+    return temp;
+
+  // At this point, the file name is valid and does not contain slashes. Search
+  // for it through the directories specified in the PATH environment variable.
+
+  // Get the path. If its empty, we can't do anything to find it.
+  const char *PathStr = getenv("PATH");
+  if (PathStr == 0)
+    return Path();
+
+  // Now we have a colon separated list of directories to search; try them.
+  size_t PathLen = strlen(PathStr);
+  while (PathLen) {
+    // Find the first colon...
+    const char *Colon = std::find(PathStr, PathStr+PathLen, ':');
+
+    // Check to see if this first directory contains the executable...
+    Path FilePath;
+    if (FilePath.set(std::string(PathStr,Colon))) {
+      FilePath.appendComponent(progName);
+      if (FilePath.canExecute())
+        return FilePath;                    // Found the executable!
+    }
+
+    // Nope it wasn't in this directory, check the next path in the list!
+    PathLen -= Colon-PathStr;
+    PathStr = Colon;
+
+    // Advance past duplicate colons
+    while (*PathStr == ':') {
+      PathStr++;
+      PathLen--;
+    }
+  }
+  return Path();
+}
+
+static bool RedirectIO(const Path *Path, int FD, std::string* ErrMsg) {
+  if (Path == 0) // Noop
+    return false;
+  const char *File;
+  if (Path->isEmpty())
+    // Redirect empty paths to /dev/null
+    File = "/dev/null";
+  else
+    File = Path->c_str();
+
+  // Open the file
+  int InFD = open(File, FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666);
+  if (InFD == -1) {
+    MakeErrMsg(ErrMsg, "Cannot open file '" + std::string(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 Path *Path, int FD, std::string *ErrMsg,
+                          posix_spawn_file_actions_t &FileActions) {
+  if (Path == 0) // Noop
+    return false;
+  const char *File;
+  if (Path->isEmpty())
+    // 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.
+  // Virtual memory.
+  getrlimit (RLIMIT_AS, &r);
+  r.rlim_cur = limit;
+  setrlimit (RLIMIT_AS, &r);
+#endif
+#endif
+}
+
+bool
+Program::Execute(const Path &path, const char **args, const char **envp,
+                 const Path **redirects, unsigned memoryLimit,
+                  std::string *ErrMsg) {
+  // 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 FileActions;
+    posix_spawn_file_actions_init(&FileActions);
+
+    if (redirects) {
+      // Redirect stdin/stdout.
+      if (RedirectIO_PS(redirects[0], 0, ErrMsg, FileActions) ||
+          RedirectIO_PS(redirects[1], 1, ErrMsg, FileActions))
+        return false;
+      if (redirects[1] == 0 || redirects[2] == 0 ||
+          *redirects[1] != *redirects[2]) {
+        // Just redirect stderr
+        if (RedirectIO_PS(redirects[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 !defined(__APPLE__)
+      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, path.c_str(), &FileActions, /*attrp*/0,
+                          const_cast<char **>(args), const_cast<char **>(envp));
+
+    posix_spawn_file_actions_destroy(&FileActions);
+
+    if (Err)
+     return !MakeErrMsg(ErrMsg, "posix_spawn failed", Err);
+
+    Data_ = reinterpret_cast<void*>(PID);
+    return true;
+  }
+#endif
+
+  // Create a child process.
+  int child = fork();
+  switch (child) {
+    // An error occured:  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!
+      if (envp != 0)
+        execve(path.c_str(),
+               const_cast<char **>(args),
+               const_cast<char **>(envp));
+      else
+        execv(path.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;
+  }
+
+  Data_ = reinterpret_cast<void*>(child);
+
+  return true;
+}
+
+int
+Program::Wait(const sys::Path &path,
+              unsigned secondsToWait,
+              std::string* ErrMsg)
+{
+#ifdef HAVE_SYS_WAIT_H
+  struct sigaction Act, Old;
+
+  if (Data_ == 0) {
+    MakeErrMsg(ErrMsg, "Process not started!");
+    return -1;
+  }
+
+  // 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.
+  if (secondsToWait) {
+    memset(&Act, 0, sizeof(Act));
+    Act.sa_handler = TimeOutHandler;
+    sigemptyset(&Act.sa_mask);
+    sigaction(SIGALRM, &Act, &Old);
+    alarm(secondsToWait);
+  }
+
+  // Parent process: Wait for the child process to terminate.
+  int status;
+  uint64_t pid = reinterpret_cast<uint64_t>(Data_);
+  pid_t child = static_cast<pid_t>(pid);
+  while (waitpid(pid, &status, 0) != child)
+    if (secondsToWait && errno == EINTR) {
+      // Kill the child.
+      kill(child, SIGKILL);
+
+      // Turn off the alarm and restore the signal handler
+      alarm(0);
+      sigaction(SIGALRM, &Old, 0);
+
+      // Wait for child to die
+      if (wait(&status) != child)
+        MakeErrMsg(ErrMsg, "Child timed out but wouldn't die");
+      else
+        MakeErrMsg(ErrMsg, "Child timed out", 0);
+
+      return -1;   // Timeout detected
+    } else if (errno != EINTR) {
+      MakeErrMsg(ErrMsg, "Error waiting for child process");
+      return -1;
+    }
+
+  // We exited normally without timeout, so turn off the timer.
+  if (secondsToWait) {
+    alarm(0);
+    sigaction(SIGALRM, &Old, 0);
+  }
+
+  // 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);
+#ifdef HAVE_POSIX_SPAWN
+    // The posix_spawn child process returns 127 on any kind of error.
+    // Following the POSIX convention for command-line tools (which posix_spawn
+    // itself apparently does not), check to see if the failure was due to some
+    // reason other than the file not existing, and return 126 in this case.
+    if (result == 127 && path.exists())
+      result = 126;
+#endif
+    if (result == 127) {
+      if (ErrMsg)
+        *ErrMsg = llvm::sys::StrError(ENOENT);
+      return -1;
+    }
+    if (result == 126) {
+      if (ErrMsg)
+        *ErrMsg = "Program could not be executed";
+      return -1;
+    }
+  } else if (WIFSIGNALED(status)) {
+    if (ErrMsg) {
+      *ErrMsg = strsignal(WTERMSIG(status));
+#ifdef WCOREDUMP
+      if (WCOREDUMP(status))
+        *ErrMsg += " (core dumped)";
+#endif
+    }
+    return -1;
+  }
+  return result;
+#else
+  if (ErrMsg)
+    *ErrMsg = "Program::Wait is not implemented on this platform yet!";
+  return -1;
+#endif
+}
+
+bool
+Program::Kill(std::string* ErrMsg) {
+  if (Data_ == 0) {
+    MakeErrMsg(ErrMsg, "Process not started!");
+    return true;
+  }
+
+  uint64_t pid64 = reinterpret_cast<uint64_t>(Data_);
+  pid_t pid = static_cast<pid_t>(pid64);
+
+  if (kill(pid, SIGKILL) != 0) {
+    MakeErrMsg(ErrMsg, "The process couldn't be killed!");
+    return true;
+  }
+
+  return false;
+}
+
+bool Program::ChangeStdinToBinary(){
+  // Do nothing, as Unix doesn't differentiate between text and binary.
+  return false;
+}
+
+bool Program::ChangeStdoutToBinary(){
+  // Do nothing, as Unix doesn't differentiate between text and binary.
+  return false;
+}
+
+bool Program::ChangeStderrToBinary(){
+  // Do nothing, as Unix doesn't differentiate between text and binary.
+  return false;
+}
+
+}