1 //===- llvm/System/Unix/Program.cpp -----------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the Unix specific portion of the Program class.
12 //===----------------------------------------------------------------------===//
14 //===----------------------------------------------------------------------===//
15 //=== WARNING: Implementation here must contain only generic UNIX code that
16 //=== is guaranteed to work on *all* UNIX variants.
17 //===----------------------------------------------------------------------===//
19 #include <llvm/Config/config.h>
24 #if HAVE_SYS_RESOURCE_H
25 #include <sys/resource.h>
33 #ifdef HAVE_POSIX_SPAWN
35 #if !defined(__APPLE__)
36 extern char **environ;
38 #include <crt_externs.h> // _NSGetEnviron
45 Program::Program() : Data_(0) {}
47 Program::~Program() {}
49 unsigned Program::GetPid() const {
50 uint64_t pid = reinterpret_cast<uint64_t>(Data_);
51 return static_cast<unsigned>(pid);
54 // This function just uses the PATH environment variable to find the program.
56 Program::FindProgramByName(const std::string& progName) {
58 // Check some degenerate cases
59 if (progName.length() == 0) // no program
62 if (!temp.set(progName)) // invalid name
64 // Use the given path verbatim if it contains any slashes; this matches
65 // the behavior of sh(1) and friends.
66 if (progName.find('/') != std::string::npos)
69 // At this point, the file name does not contain slashes. Search for it
70 // through the directories specified in the PATH environment variable.
72 // Get the path. If its empty, we can't do anything to find it.
73 const char *PathStr = getenv("PATH");
77 // Now we have a colon separated list of directories to search; try them.
78 size_t PathLen = strlen(PathStr);
80 // Find the first colon...
81 const char *Colon = std::find(PathStr, PathStr+PathLen, ':');
83 // Check to see if this first directory contains the executable...
85 if (FilePath.set(std::string(PathStr,Colon))) {
86 FilePath.appendComponent(progName);
87 if (FilePath.canExecute())
88 return FilePath; // Found the executable!
91 // Nope it wasn't in this directory, check the next path in the list!
92 PathLen -= Colon-PathStr;
95 // Advance past duplicate colons
96 while (*PathStr == ':') {
104 static bool RedirectIO(const Path *Path, int FD, std::string* ErrMsg) {
105 if (Path == 0) // Noop
109 // Redirect empty paths to /dev/null
112 File = Path->c_str();
115 int InFD = open(File, FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666);
117 MakeErrMsg(ErrMsg, "Cannot open file '" + std::string(File) + "' for "
118 + (FD == 0 ? "input" : "output"));
122 // Install it as the requested FD
123 if (dup2(InFD, FD) == -1) {
124 MakeErrMsg(ErrMsg, "Cannot dup2");
128 close(InFD); // Close the original FD
132 #ifdef HAVE_POSIX_SPAWN
133 static bool RedirectIO_PS(const Path *Path, int FD, std::string *ErrMsg,
134 posix_spawn_file_actions_t &FileActions) {
135 if (Path == 0) // Noop
139 // Redirect empty paths to /dev/null
142 File = Path->c_str();
144 if (int Err = posix_spawn_file_actions_addopen(&FileActions, FD,
145 File, FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666))
146 return MakeErrMsg(ErrMsg, "Cannot dup2", Err);
151 static void TimeOutHandler(int Sig) {
154 static void SetMemoryLimits (unsigned size)
156 #if HAVE_SYS_RESOURCE_H && HAVE_GETRLIMIT && HAVE_SETRLIMIT
158 __typeof__ (r.rlim_cur) limit = (__typeof__ (r.rlim_cur)) (size) * 1048576;
161 getrlimit (RLIMIT_DATA, &r);
163 setrlimit (RLIMIT_DATA, &r);
165 // Resident set size.
166 getrlimit (RLIMIT_RSS, &r);
168 setrlimit (RLIMIT_RSS, &r);
170 #ifdef RLIMIT_AS // e.g. NetBSD doesn't have it.
172 getrlimit (RLIMIT_AS, &r);
174 setrlimit (RLIMIT_AS, &r);
180 Program::Execute(const Path &path, const char **args, const char **envp,
181 const Path **redirects, unsigned memoryLimit,
182 std::string *ErrMsg) {
183 // If this OS has posix_spawn and there is no memory limit being implied, use
184 // posix_spawn. It is more efficient than fork/exec.
185 #ifdef HAVE_POSIX_SPAWN
186 if (memoryLimit == 0) {
187 posix_spawn_file_actions_t FileActions;
188 posix_spawn_file_actions_init(&FileActions);
191 // Redirect stdin/stdout.
192 if (RedirectIO_PS(redirects[0], 0, ErrMsg, FileActions) ||
193 RedirectIO_PS(redirects[1], 1, ErrMsg, FileActions))
195 if (redirects[1] == 0 || redirects[2] == 0 ||
196 *redirects[1] != *redirects[2]) {
197 // Just redirect stderr
198 if (RedirectIO_PS(redirects[2], 2, ErrMsg, FileActions)) return false;
200 // If stdout and stderr should go to the same place, redirect stderr
201 // to the FD already open for stdout.
202 if (int Err = posix_spawn_file_actions_adddup2(&FileActions, 1, 2))
203 return !MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout", Err);
208 #if !defined(__APPLE__)
209 envp = const_cast<const char **>(environ);
211 // environ is missing in dylibs.
212 envp = const_cast<const char **>(*_NSGetEnviron());
216 int Err = posix_spawn(&PID, path.c_str(), &FileActions, /*attrp*/0,
217 const_cast<char **>(args), const_cast<char **>(envp));
219 posix_spawn_file_actions_destroy(&FileActions);
222 return !MakeErrMsg(ErrMsg, "posix_spawn failed", Err);
224 Data_ = reinterpret_cast<void*>(PID);
229 if (!path.canExecute()) {
231 *ErrMsg = path.str() + " is not executable";
235 // Create a child process.
238 // An error occured: Return to the caller.
240 MakeErrMsg(ErrMsg, "Couldn't fork");
243 // Child process: Execute the program.
245 // Redirect file descriptors...
248 if (RedirectIO(redirects[0], 0, ErrMsg)) { return false; }
250 if (RedirectIO(redirects[1], 1, ErrMsg)) { return false; }
251 if (redirects[1] && redirects[2] &&
252 *(redirects[1]) == *(redirects[2])) {
253 // If stdout and stderr should go to the same place, redirect stderr
254 // to the FD already open for stdout.
255 if (-1 == dup2(1,2)) {
256 MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout");
260 // Just redirect stderr
261 if (RedirectIO(redirects[2], 2, ErrMsg)) { return false; }
266 if (memoryLimit!=0) {
267 SetMemoryLimits(memoryLimit);
273 const_cast<char **>(args),
274 const_cast<char **>(envp));
277 const_cast<char **>(args));
278 // If the execve() failed, we should exit. Follow Unix protocol and
279 // return 127 if the executable was not found, and 126 otherwise.
280 // Use _exit rather than exit so that atexit functions and static
281 // object destructors cloned from the parent process aren't
282 // redundantly run, and so that any data buffered in stdio buffers
283 // cloned from the parent aren't redundantly written out.
284 _exit(errno == ENOENT ? 127 : 126);
287 // Parent process: Break out of the switch to do our processing.
292 Data_ = reinterpret_cast<void*>(child);
298 Program::Wait(unsigned secondsToWait,
301 #ifdef HAVE_SYS_WAIT_H
302 struct sigaction Act, Old;
305 MakeErrMsg(ErrMsg, "Process not started!");
309 // Install a timeout handler. The handler itself does nothing, but the simple
310 // fact of having a handler at all causes the wait below to return with EINTR,
311 // unlike if we used SIG_IGN.
313 #if !defined(__HAIKU__) && !defined(__minix)
314 Act.sa_sigaction = 0;
316 Act.sa_handler = TimeOutHandler;
317 sigemptyset(&Act.sa_mask);
319 sigaction(SIGALRM, &Act, &Old);
320 alarm(secondsToWait);
323 // Parent process: Wait for the child process to terminate.
325 uint64_t pid = reinterpret_cast<uint64_t>(Data_);
326 pid_t child = static_cast<pid_t>(pid);
327 while (waitpid(pid, &status, 0) != child)
328 if (secondsToWait && errno == EINTR) {
330 kill(child, SIGKILL);
332 // Turn off the alarm and restore the signal handler
334 sigaction(SIGALRM, &Old, 0);
336 // Wait for child to die
337 if (wait(&status) != child)
338 MakeErrMsg(ErrMsg, "Child timed out but wouldn't die");
340 MakeErrMsg(ErrMsg, "Child timed out", 0);
342 return -1; // Timeout detected
343 } else if (errno != EINTR) {
344 MakeErrMsg(ErrMsg, "Error waiting for child process");
348 // We exited normally without timeout, so turn off the timer.
351 sigaction(SIGALRM, &Old, 0);
354 // Return the proper exit status. 0=success, >0 is programs' exit status,
355 // <0 means a signal was returned, -9999999 means the program dumped core.
357 if (WIFEXITED(status))
358 result = WEXITSTATUS(status);
359 else if (WIFSIGNALED(status))
360 result = 0 - WTERMSIG(status);
362 else if (WCOREDUMP(status))
363 result |= 0x01000000;
373 Program::Kill(std::string* ErrMsg) {
375 MakeErrMsg(ErrMsg, "Process not started!");
379 uint64_t pid64 = reinterpret_cast<uint64_t>(Data_);
380 pid_t pid = static_cast<pid_t>(pid64);
382 if (kill(pid, SIGKILL) != 0) {
383 MakeErrMsg(ErrMsg, "The process couldn't be killed!");
390 bool Program::ChangeStdinToBinary(){
391 // Do nothing, as Unix doesn't differentiate between text and binary.
395 bool Program::ChangeStdoutToBinary(){
396 // Do nothing, as Unix doesn't differentiate between text and binary.
400 bool Program::ChangeStderrToBinary(){
401 // Do nothing, as Unix doesn't differentiate between text and binary.