10b57cec5SDimitry Andric//===- llvm/Support/Unix/Program.cpp -----------------------------*- C++ -*-===// 20b57cec5SDimitry Andric// 30b57cec5SDimitry Andric// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 40b57cec5SDimitry Andric// See https://llvm.org/LICENSE.txt for license information. 50b57cec5SDimitry Andric// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 60b57cec5SDimitry Andric// 70b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 80b57cec5SDimitry Andric// 90b57cec5SDimitry Andric// This file implements the Unix specific portion of the Program class. 100b57cec5SDimitry Andric// 110b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 120b57cec5SDimitry Andric 130b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 140b57cec5SDimitry Andric//=== WARNING: Implementation here must contain only generic UNIX code that 150b57cec5SDimitry Andric//=== is guaranteed to work on *all* UNIX variants. 160b57cec5SDimitry Andric//===----------------------------------------------------------------------===// 170b57cec5SDimitry Andric 180b57cec5SDimitry Andric#include "Unix.h" 190b57cec5SDimitry Andric#include "llvm/ADT/StringExtras.h" 200b57cec5SDimitry Andric#include "llvm/Config/config.h" 210b57cec5SDimitry Andric#include "llvm/Support/Compiler.h" 220b57cec5SDimitry Andric#include "llvm/Support/Errc.h" 230b57cec5SDimitry Andric#include "llvm/Support/FileSystem.h" 240b57cec5SDimitry Andric#include "llvm/Support/Path.h" 250b57cec5SDimitry Andric#include "llvm/Support/StringSaver.h" 260b57cec5SDimitry Andric#include "llvm/Support/raw_ostream.h" 270b57cec5SDimitry Andric#if HAVE_SYS_STAT_H 280b57cec5SDimitry Andric#include <sys/stat.h> 290b57cec5SDimitry Andric#endif 300b57cec5SDimitry Andric#if HAVE_SYS_RESOURCE_H 310b57cec5SDimitry Andric#include <sys/resource.h> 320b57cec5SDimitry Andric#endif 330b57cec5SDimitry Andric#if HAVE_SIGNAL_H 340b57cec5SDimitry Andric#include <signal.h> 350b57cec5SDimitry Andric#endif 360b57cec5SDimitry Andric#if HAVE_FCNTL_H 370b57cec5SDimitry Andric#include <fcntl.h> 380b57cec5SDimitry Andric#endif 390b57cec5SDimitry Andric#if HAVE_UNISTD_H 400b57cec5SDimitry Andric#include <unistd.h> 410b57cec5SDimitry Andric#endif 420b57cec5SDimitry Andric#ifdef HAVE_POSIX_SPAWN 430b57cec5SDimitry Andric#include <spawn.h> 440b57cec5SDimitry Andric 450b57cec5SDimitry Andric#if defined(__APPLE__) 460b57cec5SDimitry Andric#include <TargetConditionals.h> 470b57cec5SDimitry Andric#endif 480b57cec5SDimitry Andric 490b57cec5SDimitry Andric#if defined(__APPLE__) && !(defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) 500b57cec5SDimitry Andric#define USE_NSGETENVIRON 1 510b57cec5SDimitry Andric#else 520b57cec5SDimitry Andric#define USE_NSGETENVIRON 0 530b57cec5SDimitry Andric#endif 540b57cec5SDimitry Andric 550b57cec5SDimitry Andric#if !USE_NSGETENVIRON 560b57cec5SDimitry Andric extern char **environ; 570b57cec5SDimitry Andric#else 580b57cec5SDimitry Andric#include <crt_externs.h> // _NSGetEnviron 590b57cec5SDimitry Andric#endif 600b57cec5SDimitry Andric#endif 610b57cec5SDimitry Andric 620b57cec5SDimitry Andricnamespace llvm { 630b57cec5SDimitry Andric 640b57cec5SDimitry Andricusing namespace sys; 650b57cec5SDimitry Andric 660b57cec5SDimitry AndricProcessInfo::ProcessInfo() : Pid(0), ReturnCode(0) {} 670b57cec5SDimitry Andric 680b57cec5SDimitry AndricErrorOr<std::string> sys::findProgramByName(StringRef Name, 690b57cec5SDimitry Andric ArrayRef<StringRef> Paths) { 700b57cec5SDimitry Andric assert(!Name.empty() && "Must have a name!"); 710b57cec5SDimitry Andric // Use the given path verbatim if it contains any slashes; this matches 720b57cec5SDimitry Andric // the behavior of sh(1) and friends. 730b57cec5SDimitry Andric if (Name.find('/') != StringRef::npos) 740b57cec5SDimitry Andric return std::string(Name); 750b57cec5SDimitry Andric 760b57cec5SDimitry Andric SmallVector<StringRef, 16> EnvironmentPaths; 770b57cec5SDimitry Andric if (Paths.empty()) 780b57cec5SDimitry Andric if (const char *PathEnv = std::getenv("PATH")) { 790b57cec5SDimitry Andric SplitString(PathEnv, EnvironmentPaths, ":"); 800b57cec5SDimitry Andric Paths = EnvironmentPaths; 810b57cec5SDimitry Andric } 820b57cec5SDimitry Andric 830b57cec5SDimitry Andric for (auto Path : Paths) { 840b57cec5SDimitry Andric if (Path.empty()) 850b57cec5SDimitry Andric continue; 860b57cec5SDimitry Andric 870b57cec5SDimitry Andric // Check to see if this first directory contains the executable... 880b57cec5SDimitry Andric SmallString<128> FilePath(Path); 890b57cec5SDimitry Andric sys::path::append(FilePath, Name); 900b57cec5SDimitry Andric if (sys::fs::can_execute(FilePath.c_str())) 910b57cec5SDimitry Andric return std::string(FilePath.str()); // Found the executable! 920b57cec5SDimitry Andric } 930b57cec5SDimitry Andric return errc::no_such_file_or_directory; 940b57cec5SDimitry Andric} 950b57cec5SDimitry Andric 960b57cec5SDimitry Andricstatic bool RedirectIO(Optional<StringRef> Path, int FD, std::string* ErrMsg) { 970b57cec5SDimitry Andric if (!Path) // Noop 980b57cec5SDimitry Andric return false; 990b57cec5SDimitry Andric std::string File; 1000b57cec5SDimitry Andric if (Path->empty()) 1010b57cec5SDimitry Andric // Redirect empty paths to /dev/null 1020b57cec5SDimitry Andric File = "/dev/null"; 1030b57cec5SDimitry Andric else 1040b57cec5SDimitry Andric File = *Path; 1050b57cec5SDimitry Andric 1060b57cec5SDimitry Andric // Open the file 1070b57cec5SDimitry Andric int InFD = open(File.c_str(), FD == 0 ? O_RDONLY : O_WRONLY|O_CREAT, 0666); 1080b57cec5SDimitry Andric if (InFD == -1) { 1090b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Cannot open file '" + File + "' for " 1100b57cec5SDimitry Andric + (FD == 0 ? "input" : "output")); 1110b57cec5SDimitry Andric return true; 1120b57cec5SDimitry Andric } 1130b57cec5SDimitry Andric 1140b57cec5SDimitry Andric // Install it as the requested FD 1150b57cec5SDimitry Andric if (dup2(InFD, FD) == -1) { 1160b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Cannot dup2"); 1170b57cec5SDimitry Andric close(InFD); 1180b57cec5SDimitry Andric return true; 1190b57cec5SDimitry Andric } 1200b57cec5SDimitry Andric close(InFD); // Close the original FD 1210b57cec5SDimitry Andric return false; 1220b57cec5SDimitry Andric} 1230b57cec5SDimitry Andric 1240b57cec5SDimitry Andric#ifdef HAVE_POSIX_SPAWN 1250b57cec5SDimitry Andricstatic bool RedirectIO_PS(const std::string *Path, int FD, std::string *ErrMsg, 1260b57cec5SDimitry Andric posix_spawn_file_actions_t *FileActions) { 1270b57cec5SDimitry Andric if (!Path) // Noop 1280b57cec5SDimitry Andric return false; 1290b57cec5SDimitry Andric const char *File; 1300b57cec5SDimitry Andric if (Path->empty()) 1310b57cec5SDimitry Andric // Redirect empty paths to /dev/null 1320b57cec5SDimitry Andric File = "/dev/null"; 1330b57cec5SDimitry Andric else 1340b57cec5SDimitry Andric File = Path->c_str(); 1350b57cec5SDimitry Andric 1360b57cec5SDimitry Andric if (int Err = posix_spawn_file_actions_addopen( 1370b57cec5SDimitry Andric FileActions, FD, File, 1380b57cec5SDimitry Andric FD == 0 ? O_RDONLY : O_WRONLY | O_CREAT, 0666)) 1390b57cec5SDimitry Andric return MakeErrMsg(ErrMsg, "Cannot dup2", Err); 1400b57cec5SDimitry Andric return false; 1410b57cec5SDimitry Andric} 1420b57cec5SDimitry Andric#endif 1430b57cec5SDimitry Andric 1440b57cec5SDimitry Andricstatic void TimeOutHandler(int Sig) { 1450b57cec5SDimitry Andric} 1460b57cec5SDimitry Andric 1470b57cec5SDimitry Andricstatic void SetMemoryLimits(unsigned size) { 1480b57cec5SDimitry Andric#if HAVE_SYS_RESOURCE_H && HAVE_GETRLIMIT && HAVE_SETRLIMIT 1490b57cec5SDimitry Andric struct rlimit r; 1500b57cec5SDimitry Andric __typeof__ (r.rlim_cur) limit = (__typeof__ (r.rlim_cur)) (size) * 1048576; 1510b57cec5SDimitry Andric 1520b57cec5SDimitry Andric // Heap size 1530b57cec5SDimitry Andric getrlimit (RLIMIT_DATA, &r); 1540b57cec5SDimitry Andric r.rlim_cur = limit; 1550b57cec5SDimitry Andric setrlimit (RLIMIT_DATA, &r); 1560b57cec5SDimitry Andric#ifdef RLIMIT_RSS 1570b57cec5SDimitry Andric // Resident set size. 1580b57cec5SDimitry Andric getrlimit (RLIMIT_RSS, &r); 1590b57cec5SDimitry Andric r.rlim_cur = limit; 1600b57cec5SDimitry Andric setrlimit (RLIMIT_RSS, &r); 1610b57cec5SDimitry Andric#endif 1620b57cec5SDimitry Andric#endif 1630b57cec5SDimitry Andric} 1640b57cec5SDimitry Andric 1650b57cec5SDimitry Andric} 1660b57cec5SDimitry Andric 1670b57cec5SDimitry Andricstatic std::vector<const char *> 1680b57cec5SDimitry AndrictoNullTerminatedCStringArray(ArrayRef<StringRef> Strings, StringSaver &Saver) { 1690b57cec5SDimitry Andric std::vector<const char *> Result; 1700b57cec5SDimitry Andric for (StringRef S : Strings) 1710b57cec5SDimitry Andric Result.push_back(Saver.save(S).data()); 1720b57cec5SDimitry Andric Result.push_back(nullptr); 1730b57cec5SDimitry Andric return Result; 1740b57cec5SDimitry Andric} 1750b57cec5SDimitry Andric 1760b57cec5SDimitry Andricstatic bool Execute(ProcessInfo &PI, StringRef Program, 1770b57cec5SDimitry Andric ArrayRef<StringRef> Args, Optional<ArrayRef<StringRef>> Env, 1780b57cec5SDimitry Andric ArrayRef<Optional<StringRef>> Redirects, 1790b57cec5SDimitry Andric unsigned MemoryLimit, std::string *ErrMsg) { 1800b57cec5SDimitry Andric if (!llvm::sys::fs::exists(Program)) { 1810b57cec5SDimitry Andric if (ErrMsg) 1820b57cec5SDimitry Andric *ErrMsg = std::string("Executable \"") + Program.str() + 1830b57cec5SDimitry Andric std::string("\" doesn't exist!"); 1840b57cec5SDimitry Andric return false; 1850b57cec5SDimitry Andric } 1860b57cec5SDimitry Andric 1870b57cec5SDimitry Andric BumpPtrAllocator Allocator; 1880b57cec5SDimitry Andric StringSaver Saver(Allocator); 1890b57cec5SDimitry Andric std::vector<const char *> ArgVector, EnvVector; 1900b57cec5SDimitry Andric const char **Argv = nullptr; 1910b57cec5SDimitry Andric const char **Envp = nullptr; 1920b57cec5SDimitry Andric ArgVector = toNullTerminatedCStringArray(Args, Saver); 1930b57cec5SDimitry Andric Argv = ArgVector.data(); 1940b57cec5SDimitry Andric if (Env) { 1950b57cec5SDimitry Andric EnvVector = toNullTerminatedCStringArray(*Env, Saver); 1960b57cec5SDimitry Andric Envp = EnvVector.data(); 1970b57cec5SDimitry Andric } 1980b57cec5SDimitry Andric 1990b57cec5SDimitry Andric // If this OS has posix_spawn and there is no memory limit being implied, use 2000b57cec5SDimitry Andric // posix_spawn. It is more efficient than fork/exec. 2010b57cec5SDimitry Andric#ifdef HAVE_POSIX_SPAWN 2020b57cec5SDimitry Andric if (MemoryLimit == 0) { 2030b57cec5SDimitry Andric posix_spawn_file_actions_t FileActionsStore; 2040b57cec5SDimitry Andric posix_spawn_file_actions_t *FileActions = nullptr; 2050b57cec5SDimitry Andric 2060b57cec5SDimitry Andric // If we call posix_spawn_file_actions_addopen we have to make sure the 2070b57cec5SDimitry Andric // c strings we pass to it stay alive until the call to posix_spawn, 2080b57cec5SDimitry Andric // so we copy any StringRefs into this variable. 2090b57cec5SDimitry Andric std::string RedirectsStorage[3]; 2100b57cec5SDimitry Andric 2110b57cec5SDimitry Andric if (!Redirects.empty()) { 2120b57cec5SDimitry Andric assert(Redirects.size() == 3); 2130b57cec5SDimitry Andric std::string *RedirectsStr[3] = {nullptr, nullptr, nullptr}; 2140b57cec5SDimitry Andric for (int I = 0; I < 3; ++I) { 2150b57cec5SDimitry Andric if (Redirects[I]) { 2160b57cec5SDimitry Andric RedirectsStorage[I] = *Redirects[I]; 2170b57cec5SDimitry Andric RedirectsStr[I] = &RedirectsStorage[I]; 2180b57cec5SDimitry Andric } 2190b57cec5SDimitry Andric } 2200b57cec5SDimitry Andric 2210b57cec5SDimitry Andric FileActions = &FileActionsStore; 2220b57cec5SDimitry Andric posix_spawn_file_actions_init(FileActions); 2230b57cec5SDimitry Andric 2240b57cec5SDimitry Andric // Redirect stdin/stdout. 2250b57cec5SDimitry Andric if (RedirectIO_PS(RedirectsStr[0], 0, ErrMsg, FileActions) || 2260b57cec5SDimitry Andric RedirectIO_PS(RedirectsStr[1], 1, ErrMsg, FileActions)) 2270b57cec5SDimitry Andric return false; 2280b57cec5SDimitry Andric if (!Redirects[1] || !Redirects[2] || *Redirects[1] != *Redirects[2]) { 2290b57cec5SDimitry Andric // Just redirect stderr 2300b57cec5SDimitry Andric if (RedirectIO_PS(RedirectsStr[2], 2, ErrMsg, FileActions)) 2310b57cec5SDimitry Andric return false; 2320b57cec5SDimitry Andric } else { 2330b57cec5SDimitry Andric // If stdout and stderr should go to the same place, redirect stderr 2340b57cec5SDimitry Andric // to the FD already open for stdout. 2350b57cec5SDimitry Andric if (int Err = posix_spawn_file_actions_adddup2(FileActions, 1, 2)) 2360b57cec5SDimitry Andric return !MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout", Err); 2370b57cec5SDimitry Andric } 2380b57cec5SDimitry Andric } 2390b57cec5SDimitry Andric 2400b57cec5SDimitry Andric if (!Envp) 2410b57cec5SDimitry Andric#if !USE_NSGETENVIRON 2420b57cec5SDimitry Andric Envp = const_cast<const char **>(environ); 2430b57cec5SDimitry Andric#else 2440b57cec5SDimitry Andric // environ is missing in dylibs. 2450b57cec5SDimitry Andric Envp = const_cast<const char **>(*_NSGetEnviron()); 2460b57cec5SDimitry Andric#endif 2470b57cec5SDimitry Andric 2480b57cec5SDimitry Andric constexpr int maxRetries = 8; 2490b57cec5SDimitry Andric int retries = 0; 2500b57cec5SDimitry Andric pid_t PID; 2510b57cec5SDimitry Andric int Err; 2520b57cec5SDimitry Andric do { 2530b57cec5SDimitry Andric PID = 0; // Make Valgrind happy. 2540b57cec5SDimitry Andric Err = posix_spawn(&PID, Program.str().c_str(), FileActions, 2550b57cec5SDimitry Andric /*attrp*/ nullptr, const_cast<char **>(Argv), 2560b57cec5SDimitry Andric const_cast<char **>(Envp)); 2570b57cec5SDimitry Andric } while (Err == EINTR && ++retries < maxRetries); 2580b57cec5SDimitry Andric 2590b57cec5SDimitry Andric if (FileActions) 2600b57cec5SDimitry Andric posix_spawn_file_actions_destroy(FileActions); 2610b57cec5SDimitry Andric 2620b57cec5SDimitry Andric if (Err) 2630b57cec5SDimitry Andric return !MakeErrMsg(ErrMsg, "posix_spawn failed", Err); 2640b57cec5SDimitry Andric 2650b57cec5SDimitry Andric PI.Pid = PID; 2660b57cec5SDimitry Andric PI.Process = PID; 2670b57cec5SDimitry Andric 2680b57cec5SDimitry Andric return true; 2690b57cec5SDimitry Andric } 2700b57cec5SDimitry Andric#endif 2710b57cec5SDimitry Andric 2720b57cec5SDimitry Andric // Create a child process. 2730b57cec5SDimitry Andric int child = fork(); 2740b57cec5SDimitry Andric switch (child) { 2750b57cec5SDimitry Andric // An error occurred: Return to the caller. 2760b57cec5SDimitry Andric case -1: 2770b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Couldn't fork"); 2780b57cec5SDimitry Andric return false; 2790b57cec5SDimitry Andric 2800b57cec5SDimitry Andric // Child process: Execute the program. 2810b57cec5SDimitry Andric case 0: { 2820b57cec5SDimitry Andric // Redirect file descriptors... 2830b57cec5SDimitry Andric if (!Redirects.empty()) { 2840b57cec5SDimitry Andric // Redirect stdin 2850b57cec5SDimitry Andric if (RedirectIO(Redirects[0], 0, ErrMsg)) { return false; } 2860b57cec5SDimitry Andric // Redirect stdout 2870b57cec5SDimitry Andric if (RedirectIO(Redirects[1], 1, ErrMsg)) { return false; } 2880b57cec5SDimitry Andric if (Redirects[1] && Redirects[2] && *Redirects[1] == *Redirects[2]) { 2890b57cec5SDimitry Andric // If stdout and stderr should go to the same place, redirect stderr 2900b57cec5SDimitry Andric // to the FD already open for stdout. 2910b57cec5SDimitry Andric if (-1 == dup2(1,2)) { 2920b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Can't redirect stderr to stdout"); 2930b57cec5SDimitry Andric return false; 2940b57cec5SDimitry Andric } 2950b57cec5SDimitry Andric } else { 2960b57cec5SDimitry Andric // Just redirect stderr 2970b57cec5SDimitry Andric if (RedirectIO(Redirects[2], 2, ErrMsg)) { return false; } 2980b57cec5SDimitry Andric } 2990b57cec5SDimitry Andric } 3000b57cec5SDimitry Andric 3010b57cec5SDimitry Andric // Set memory limits 3020b57cec5SDimitry Andric if (MemoryLimit!=0) { 3030b57cec5SDimitry Andric SetMemoryLimits(MemoryLimit); 3040b57cec5SDimitry Andric } 3050b57cec5SDimitry Andric 3060b57cec5SDimitry Andric // Execute! 3070b57cec5SDimitry Andric std::string PathStr = Program; 3080b57cec5SDimitry Andric if (Envp != nullptr) 3090b57cec5SDimitry Andric execve(PathStr.c_str(), const_cast<char **>(Argv), 3100b57cec5SDimitry Andric const_cast<char **>(Envp)); 3110b57cec5SDimitry Andric else 3120b57cec5SDimitry Andric execv(PathStr.c_str(), const_cast<char **>(Argv)); 3130b57cec5SDimitry Andric // If the execve() failed, we should exit. Follow Unix protocol and 3140b57cec5SDimitry Andric // return 127 if the executable was not found, and 126 otherwise. 3150b57cec5SDimitry Andric // Use _exit rather than exit so that atexit functions and static 3160b57cec5SDimitry Andric // object destructors cloned from the parent process aren't 3170b57cec5SDimitry Andric // redundantly run, and so that any data buffered in stdio buffers 3180b57cec5SDimitry Andric // cloned from the parent aren't redundantly written out. 3190b57cec5SDimitry Andric _exit(errno == ENOENT ? 127 : 126); 3200b57cec5SDimitry Andric } 3210b57cec5SDimitry Andric 3220b57cec5SDimitry Andric // Parent process: Break out of the switch to do our processing. 3230b57cec5SDimitry Andric default: 3240b57cec5SDimitry Andric break; 3250b57cec5SDimitry Andric } 3260b57cec5SDimitry Andric 3270b57cec5SDimitry Andric PI.Pid = child; 3280b57cec5SDimitry Andric PI.Process = child; 3290b57cec5SDimitry Andric 3300b57cec5SDimitry Andric return true; 3310b57cec5SDimitry Andric} 3320b57cec5SDimitry Andric 3330b57cec5SDimitry Andricnamespace llvm { 3340b57cec5SDimitry Andric 3350b57cec5SDimitry AndricProcessInfo sys::Wait(const ProcessInfo &PI, unsigned SecondsToWait, 3360b57cec5SDimitry Andric bool WaitUntilTerminates, std::string *ErrMsg) { 3370b57cec5SDimitry Andric struct sigaction Act, Old; 3380b57cec5SDimitry Andric assert(PI.Pid && "invalid pid to wait on, process not started?"); 3390b57cec5SDimitry Andric 3400b57cec5SDimitry Andric int WaitPidOptions = 0; 3410b57cec5SDimitry Andric pid_t ChildPid = PI.Pid; 3420b57cec5SDimitry Andric if (WaitUntilTerminates) { 3430b57cec5SDimitry Andric SecondsToWait = 0; 3440b57cec5SDimitry Andric } else if (SecondsToWait) { 3450b57cec5SDimitry Andric // Install a timeout handler. The handler itself does nothing, but the 3460b57cec5SDimitry Andric // simple fact of having a handler at all causes the wait below to return 3470b57cec5SDimitry Andric // with EINTR, unlike if we used SIG_IGN. 3480b57cec5SDimitry Andric memset(&Act, 0, sizeof(Act)); 3490b57cec5SDimitry Andric Act.sa_handler = TimeOutHandler; 3500b57cec5SDimitry Andric sigemptyset(&Act.sa_mask); 3510b57cec5SDimitry Andric sigaction(SIGALRM, &Act, &Old); 3520b57cec5SDimitry Andric alarm(SecondsToWait); 3530b57cec5SDimitry Andric } else if (SecondsToWait == 0) 3540b57cec5SDimitry Andric WaitPidOptions = WNOHANG; 3550b57cec5SDimitry Andric 3560b57cec5SDimitry Andric // Parent process: Wait for the child process to terminate. 3570b57cec5SDimitry Andric int status; 3580b57cec5SDimitry Andric ProcessInfo WaitResult; 3590b57cec5SDimitry Andric 3600b57cec5SDimitry Andric do { 3610b57cec5SDimitry Andric WaitResult.Pid = waitpid(ChildPid, &status, WaitPidOptions); 3620b57cec5SDimitry Andric } while (WaitUntilTerminates && WaitResult.Pid == -1 && errno == EINTR); 3630b57cec5SDimitry Andric 3640b57cec5SDimitry Andric if (WaitResult.Pid != PI.Pid) { 3650b57cec5SDimitry Andric if (WaitResult.Pid == 0) { 3660b57cec5SDimitry Andric // Non-blocking wait. 3670b57cec5SDimitry Andric return WaitResult; 3680b57cec5SDimitry Andric } else { 3690b57cec5SDimitry Andric if (SecondsToWait && errno == EINTR) { 3700b57cec5SDimitry Andric // Kill the child. 3710b57cec5SDimitry Andric kill(PI.Pid, SIGKILL); 3720b57cec5SDimitry Andric 3730b57cec5SDimitry Andric // Turn off the alarm and restore the signal handler 3740b57cec5SDimitry Andric alarm(0); 3750b57cec5SDimitry Andric sigaction(SIGALRM, &Old, nullptr); 3760b57cec5SDimitry Andric 3770b57cec5SDimitry Andric // Wait for child to die 3780b57cec5SDimitry Andric if (wait(&status) != ChildPid) 3790b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Child timed out but wouldn't die"); 3800b57cec5SDimitry Andric else 3810b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Child timed out", 0); 3820b57cec5SDimitry Andric 3830b57cec5SDimitry Andric WaitResult.ReturnCode = -2; // Timeout detected 3840b57cec5SDimitry Andric return WaitResult; 3850b57cec5SDimitry Andric } else if (errno != EINTR) { 3860b57cec5SDimitry Andric MakeErrMsg(ErrMsg, "Error waiting for child process"); 3870b57cec5SDimitry Andric WaitResult.ReturnCode = -1; 3880b57cec5SDimitry Andric return WaitResult; 3890b57cec5SDimitry Andric } 3900b57cec5SDimitry Andric } 3910b57cec5SDimitry Andric } 3920b57cec5SDimitry Andric 3930b57cec5SDimitry Andric // We exited normally without timeout, so turn off the timer. 3940b57cec5SDimitry Andric if (SecondsToWait && !WaitUntilTerminates) { 3950b57cec5SDimitry Andric alarm(0); 3960b57cec5SDimitry Andric sigaction(SIGALRM, &Old, nullptr); 3970b57cec5SDimitry Andric } 3980b57cec5SDimitry Andric 3990b57cec5SDimitry Andric // Return the proper exit status. Detect error conditions 4000b57cec5SDimitry Andric // so we can return -1 for them and set ErrMsg informatively. 4010b57cec5SDimitry Andric int result = 0; 4020b57cec5SDimitry Andric if (WIFEXITED(status)) { 4030b57cec5SDimitry Andric result = WEXITSTATUS(status); 4040b57cec5SDimitry Andric WaitResult.ReturnCode = result; 4050b57cec5SDimitry Andric 4060b57cec5SDimitry Andric if (result == 127) { 4070b57cec5SDimitry Andric if (ErrMsg) 4080b57cec5SDimitry Andric *ErrMsg = llvm::sys::StrError(ENOENT); 4090b57cec5SDimitry Andric WaitResult.ReturnCode = -1; 4100b57cec5SDimitry Andric return WaitResult; 4110b57cec5SDimitry Andric } 4120b57cec5SDimitry Andric if (result == 126) { 4130b57cec5SDimitry Andric if (ErrMsg) 4140b57cec5SDimitry Andric *ErrMsg = "Program could not be executed"; 4150b57cec5SDimitry Andric WaitResult.ReturnCode = -1; 4160b57cec5SDimitry Andric return WaitResult; 4170b57cec5SDimitry Andric } 4180b57cec5SDimitry Andric } else if (WIFSIGNALED(status)) { 4190b57cec5SDimitry Andric if (ErrMsg) { 4200b57cec5SDimitry Andric *ErrMsg = strsignal(WTERMSIG(status)); 4210b57cec5SDimitry Andric#ifdef WCOREDUMP 4220b57cec5SDimitry Andric if (WCOREDUMP(status)) 4230b57cec5SDimitry Andric *ErrMsg += " (core dumped)"; 4240b57cec5SDimitry Andric#endif 4250b57cec5SDimitry Andric } 4260b57cec5SDimitry Andric // Return a special value to indicate that the process received an unhandled 4270b57cec5SDimitry Andric // signal during execution as opposed to failing to execute. 4280b57cec5SDimitry Andric WaitResult.ReturnCode = -2; 4290b57cec5SDimitry Andric } 4300b57cec5SDimitry Andric return WaitResult; 4310b57cec5SDimitry Andric} 4320b57cec5SDimitry Andric 4330b57cec5SDimitry Andricstd::error_code sys::ChangeStdinToBinary() { 4340b57cec5SDimitry Andric // Do nothing, as Unix doesn't differentiate between text and binary. 4350b57cec5SDimitry Andric return std::error_code(); 4360b57cec5SDimitry Andric} 4370b57cec5SDimitry Andric 4380b57cec5SDimitry Andricstd::error_code sys::ChangeStdoutToBinary() { 4390b57cec5SDimitry Andric // Do nothing, as Unix doesn't differentiate between text and binary. 4400b57cec5SDimitry Andric return std::error_code(); 4410b57cec5SDimitry Andric} 4420b57cec5SDimitry Andric 4430b57cec5SDimitry Andricstd::error_code 4440b57cec5SDimitry Andricllvm::sys::writeFileWithEncoding(StringRef FileName, StringRef Contents, 4450b57cec5SDimitry Andric WindowsEncodingMethod Encoding /*unused*/) { 4460b57cec5SDimitry Andric std::error_code EC; 4470b57cec5SDimitry Andric llvm::raw_fd_ostream OS(FileName, EC, llvm::sys::fs::OpenFlags::F_Text); 4480b57cec5SDimitry Andric 4490b57cec5SDimitry Andric if (EC) 4500b57cec5SDimitry Andric return EC; 4510b57cec5SDimitry Andric 4520b57cec5SDimitry Andric OS << Contents; 4530b57cec5SDimitry Andric 4540b57cec5SDimitry Andric if (OS.has_error()) 4550b57cec5SDimitry Andric return make_error_code(errc::io_error); 4560b57cec5SDimitry Andric 4570b57cec5SDimitry Andric return EC; 4580b57cec5SDimitry Andric} 4590b57cec5SDimitry Andric 4600b57cec5SDimitry Andricbool llvm::sys::commandLineFitsWithinSystemLimits(StringRef Program, 4610b57cec5SDimitry Andric ArrayRef<StringRef> Args) { 4620b57cec5SDimitry Andric static long ArgMax = sysconf(_SC_ARG_MAX); 4630b57cec5SDimitry Andric // POSIX requires that _POSIX_ARG_MAX is 4096, which is the lowest possible 4640b57cec5SDimitry Andric // value for ARG_MAX on a POSIX compliant system. 4650b57cec5SDimitry Andric static long ArgMin = _POSIX_ARG_MAX; 4660b57cec5SDimitry Andric 4670b57cec5SDimitry Andric // This the same baseline used by xargs. 4680b57cec5SDimitry Andric long EffectiveArgMax = 128 * 1024; 4690b57cec5SDimitry Andric 4700b57cec5SDimitry Andric if (EffectiveArgMax > ArgMax) 4710b57cec5SDimitry Andric EffectiveArgMax = ArgMax; 4720b57cec5SDimitry Andric else if (EffectiveArgMax < ArgMin) 4730b57cec5SDimitry Andric EffectiveArgMax = ArgMin; 4740b57cec5SDimitry Andric 4750b57cec5SDimitry Andric // System says no practical limit. 4760b57cec5SDimitry Andric if (ArgMax == -1) 4770b57cec5SDimitry Andric return true; 4780b57cec5SDimitry Andric 4790b57cec5SDimitry Andric // Conservatively account for space required by environment variables. 4800b57cec5SDimitry Andric long HalfArgMax = EffectiveArgMax / 2; 4810b57cec5SDimitry Andric 4820b57cec5SDimitry Andric size_t ArgLength = Program.size() + 1; 4830b57cec5SDimitry Andric for (StringRef Arg : Args) { 4840b57cec5SDimitry Andric // Ensure that we do not exceed the MAX_ARG_STRLEN constant on Linux, which 4850b57cec5SDimitry Andric // does not have a constant unlike what the man pages would have you 4860b57cec5SDimitry Andric // believe. Since this limit is pretty high, perform the check 4870b57cec5SDimitry Andric // unconditionally rather than trying to be aggressive and limiting it to 4880b57cec5SDimitry Andric // Linux only. 4890b57cec5SDimitry Andric if (Arg.size() >= (32 * 4096)) 4900b57cec5SDimitry Andric return false; 4910b57cec5SDimitry Andric 4920b57cec5SDimitry Andric ArgLength += Arg.size() + 1; 4930b57cec5SDimitry Andric if (ArgLength > size_t(HalfArgMax)) { 4940b57cec5SDimitry Andric return false; 4950b57cec5SDimitry Andric } 4960b57cec5SDimitry Andric } 4970b57cec5SDimitry Andric 4980b57cec5SDimitry Andric return true; 4990b57cec5SDimitry Andric} 5000b57cec5SDimitry Andric} 501