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>
37 Program::Program() : Data_(0) {}
39 Program::~Program() {}
41 unsigned Program::GetPid() const {
42 uint64_t pid = reinterpret_cast<uint64_t>(Data_);
43 return static_cast<unsigned>(pid);
46 // This function just uses the PATH environment variable to find the program.
48 Program::FindProgramByName(const std::string& progName) {
50 // Check some degenerate cases
51 if (progName.length() == 0) // no program
54 if (!temp.set(progName)) // invalid name
56 // Use the given path verbatim if it contains any slashes; this matches
57 // the behavior of sh(1) and friends.
58 if (progName.find('/') != std::string::npos)
61 // At this point, the file name does not contain slashes. Search for it
62 // through the directories specified in the PATH environment variable.
64 // Get the path. If its empty, we can't do anything to find it.
65 const char *PathStr = getenv("PATH");
69 // Now we have a colon separated list of directories to search; try them.
70 size_t PathLen = strlen(PathStr);
72 // Find the first colon...
73 const char *Colon = std::find(PathStr, PathStr+PathLen, ':');
75 // Check to see if this first directory contains the executable...
77 if (FilePath.set(std::string(PathStr,Colon))) {
78 FilePath.appendComponent(progName);
79 if (FilePath.canExecute())
80 return FilePath; // Found the executable!
83 // Nope it wasn't in this directory, check the next path in the list!
84 PathLen -= Colon-PathStr;
87 // Advance past duplicate colons
88 while (*PathStr == ':') {
96 static bool RedirectIO(const Path *Path, int FD, std::string* ErrMsg) {
102 // Redirect empty paths to /dev/null
108 int InFD = open(File.c_str(), FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666);
110 MakeErrMsg(ErrMsg, "Cannot open file '" + File + "' for "
111 + (FD == 0 ? "input" : "output"));
115 // Install it as the requested FD
116 if (-1 == dup2(InFD, FD)) {
117 MakeErrMsg(ErrMsg, "Cannot dup2");
120 close(InFD); // Close the original FD
124 static void TimeOutHandler(int Sig) {
127 static void SetMemoryLimits (unsigned size)
129 #if HAVE_SYS_RESOURCE_H
131 __typeof__ (r.rlim_cur) limit = (__typeof__ (r.rlim_cur)) (size) * 1048576;
134 getrlimit (RLIMIT_DATA, &r);
136 setrlimit (RLIMIT_DATA, &r);
138 // Resident set size.
139 getrlimit (RLIMIT_RSS, &r);
141 setrlimit (RLIMIT_RSS, &r);
143 #ifdef RLIMIT_AS // e.g. NetBSD doesn't have it.
145 getrlimit (RLIMIT_AS, &r);
147 setrlimit (RLIMIT_AS, &r);
153 Program::Execute(const Path& path,
156 const Path** redirects,
157 unsigned memoryLimit,
160 if (!path.canExecute()) {
162 *ErrMsg = path.str() + " is not executable";
166 // Create a child process.
169 // An error occured: Return to the caller.
171 MakeErrMsg(ErrMsg, "Couldn't fork");
174 // Child process: Execute the program.
176 // Redirect file descriptors...
179 if (RedirectIO(redirects[0], 0, ErrMsg)) { return false; }
181 if (RedirectIO(redirects[1], 1, ErrMsg)) { return false; }
182 if (redirects[1] && redirects[2] &&
183 *(redirects[1]) == *(redirects[2])) {
184 // If stdout and stderr should go to the same place, redirect stderr
185 // to the FD already open for stdout.
186 if (-1 == dup2(1,2)) {
187 MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout");
191 // Just redirect stderr
192 if (RedirectIO(redirects[2], 2, ErrMsg)) { return false; }
197 if (memoryLimit!=0) {
198 SetMemoryLimits(memoryLimit);
203 execve(path.c_str(), (char**)args, (char**)envp);
205 execv(path.c_str(), (char**)args);
206 // If the execve() failed, we should exit. Follow Unix protocol and
207 // return 127 if the executable was not found, and 126 otherwise.
208 // Use _exit rather than exit so that atexit functions and static
209 // object destructors cloned from the parent process aren't
210 // redundantly run, and so that any data buffered in stdio buffers
211 // cloned from the parent aren't redundantly written out.
212 _exit(errno == ENOENT ? 127 : 126);
215 // Parent process: Break out of the switch to do our processing.
220 Data_ = reinterpret_cast<void*>(child);
226 Program::Wait(unsigned secondsToWait,
229 #ifdef HAVE_SYS_WAIT_H
230 struct sigaction Act, Old;
233 MakeErrMsg(ErrMsg, "Process not started!");
237 // Install a timeout handler. The handler itself does nothing, but the simple
238 // fact of having a handler at all causes the wait below to return with EINTR,
239 // unlike if we used SIG_IGN.
241 Act.sa_sigaction = 0;
242 Act.sa_handler = TimeOutHandler;
243 sigemptyset(&Act.sa_mask);
245 sigaction(SIGALRM, &Act, &Old);
246 alarm(secondsToWait);
249 // Parent process: Wait for the child process to terminate.
251 uint64_t pid = reinterpret_cast<uint64_t>(Data_);
252 pid_t child = static_cast<pid_t>(pid);
253 while (waitpid(pid, &status, 0) != child)
254 if (secondsToWait && errno == EINTR) {
256 kill(child, SIGKILL);
258 // Turn off the alarm and restore the signal handler
260 sigaction(SIGALRM, &Old, 0);
262 // Wait for child to die
263 if (wait(&status) != child)
264 MakeErrMsg(ErrMsg, "Child timed out but wouldn't die");
266 MakeErrMsg(ErrMsg, "Child timed out", 0);
268 return -1; // Timeout detected
269 } else if (errno != EINTR) {
270 MakeErrMsg(ErrMsg, "Error waiting for child process");
274 // We exited normally without timeout, so turn off the timer.
277 sigaction(SIGALRM, &Old, 0);
280 // Return the proper exit status. 0=success, >0 is programs' exit status,
281 // <0 means a signal was returned, -9999999 means the program dumped core.
283 if (WIFEXITED(status))
284 result = WEXITSTATUS(status);
285 else if (WIFSIGNALED(status))
286 result = 0 - WTERMSIG(status);
288 else if (WCOREDUMP(status))
289 result |= 0x01000000;
299 Program::Kill(std::string* ErrMsg) {
301 MakeErrMsg(ErrMsg, "Process not started!");
305 uint64_t pid64 = reinterpret_cast<uint64_t>(Data_);
306 pid_t pid = static_cast<pid_t>(pid64);
308 if (kill(pid, SIGKILL) != 0) {
309 MakeErrMsg(ErrMsg, "The process couldn't be killed!");
316 bool Program::ChangeStdinToBinary(){
317 // Do nothing, as Unix doesn't differentiate between text and binary.
321 bool Program::ChangeStdoutToBinary(){
322 // Do nothing, as Unix doesn't differentiate between text and binary.