//===- llvm/System/Unix/Program.cpp -----------------------------*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by Reid Spencer and is distributed under the
-// University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+// 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.
#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>
-#ifdef HAVE_SYS_WAIT_H
-#include <sys/wait.h>
#endif
-
-extern char** environ;
+#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) {
if (progName.length() == 0) // no program
return Path();
Path temp;
- if (!temp.setFile(progName)) // invalid name
+ if (!temp.set(progName)) // invalid name
return Path();
- if (temp.executable()) // already executable as is
+ // 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 its not executable
-
+ // 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)
+ if (PathStr == 0)
return Path();
// Now we have a colon separated list of directories to search; try them.
- unsigned PathLen = strlen(PathStr);
+ 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.setDirectory(std::string(PathStr,Colon))) {
- FilePath.appendFile(progName);
- if (FilePath.executable())
+ if (FilePath.set(std::string(PathStr,Colon))) {
+ FilePath.appendComponent(progName);
+ if (FilePath.canExecute())
return FilePath; // Found the executable!
}
return Path();
}
-//
-int
-Program::ExecuteAndWait(const Path& path,
- const std::vector<std::string>& args) {
- if (!path.executable())
- throw path.toString() + " is not executable";
+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();
-#ifdef HAVE_SYS_WAIT_H
- // Create local versions of the parameters that can be passed into execve()
- // without creating const problems.
- const char* argv[ args.size() + 2 ];
- unsigned index = 0;
- std::string progname(path.getLast());
- argv[index++] = progname.c_str();
- for (unsigned i = 0; i < args.size(); i++)
- argv[index++] = args[i].c_str();
- argv[index] = 0;
+ // 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.
- switch (fork()) {
+ int child = fork();
+ switch (child) {
// An error occured: Return to the caller.
case -1:
- ThrowErrno(std::string("Couldn't execute program '") + path.toString() +
- "'");
- break;
+ MakeErrMsg(ErrMsg, "Couldn't fork");
+ return false;
// Child process: Execute the program.
- case 0:
- execve (path.c_str(), (char** const)argv, environ);
- // If the execve() failed, we should exit and let the parent pick up
- // our non-zero exit status.
- exit (errno);
+ 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;
- if ((::wait (&status)) == -1)
- ThrowErrno(std::string("Failed waiting for program '") + path.toString()
- + "'");
-
- // If the program exited normally with a zero exit status, return success!
- if (WIFEXITED (status))
- return WEXITSTATUS(status);
- else if (WIFSIGNALED(status))
- throw std::string("Program '") + path.toString() +
- "' received terminating signal.";
- else
- return 0;
-
+ 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
- throw std::string("Program::ExecuteAndWait not implemented on this platform!\n");
+ 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;
}
}
-// vim: sw=2 smartindent smarttab tw=80 autoindent expandtab