1 //===-- ExecuteFunction implementation for Unix-like Systems --------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "ExecuteFunction.h" 10 #include "src/__support/macros/config.h" 11 #include <cassert> 12 #include <cstdlib> 13 #include <cstring> 14 #include <iostream> 15 #include <memory> 16 #include <poll.h> 17 #include <signal.h> 18 #include <sys/wait.h> 19 #include <unistd.h> 20 21 namespace LIBC_NAMESPACE_DECL { 22 namespace testutils { 23 24 bool ProcessStatus::exited_normally() { return WIFEXITED(platform_defined); } 25 26 int ProcessStatus::get_exit_code() { 27 assert(exited_normally() && "Abnormal termination, no exit code"); 28 return WEXITSTATUS(platform_defined); 29 } 30 31 int ProcessStatus::get_fatal_signal() { 32 if (exited_normally()) 33 return 0; 34 return WTERMSIG(platform_defined); 35 } 36 37 ProcessStatus invoke_in_subprocess(FunctionCaller *func, unsigned timeout_ms) { 38 std::unique_ptr<FunctionCaller> X(func); 39 int pipe_fds[2]; 40 if (::pipe(pipe_fds) == -1) 41 return ProcessStatus::error("pipe(2) failed"); 42 43 // Don't copy the buffers into the child process and print twice. 44 std::cout.flush(); 45 std::cerr.flush(); 46 pid_t pid = ::fork(); 47 if (pid == -1) 48 return ProcessStatus::error("fork(2) failed"); 49 50 if (!pid) { 51 (*func)(); 52 std::exit(0); 53 } 54 ::close(pipe_fds[1]); 55 56 struct pollfd poll_fd { 57 pipe_fds[0], 0, 0 58 }; 59 // No events requested so this call will only return after the timeout or if 60 // the pipes peer was closed, signaling the process exited. 61 if (::poll(&poll_fd, 1, timeout_ms) == -1) 62 return ProcessStatus::error("poll(2) failed"); 63 // If the pipe wasn't closed by the child yet then timeout has expired. 64 if (!(poll_fd.revents & POLLHUP)) { 65 ::kill(pid, SIGKILL); 66 return ProcessStatus::timed_out_ps(); 67 } 68 69 int wstatus = 0; 70 // Wait on the pid of the subprocess here so it gets collected by the system 71 // and doesn't turn into a zombie. 72 pid_t status = ::waitpid(pid, &wstatus, 0); 73 if (status == -1) 74 return ProcessStatus::error("waitpid(2) failed"); 75 assert(status == pid); 76 return {wstatus}; 77 } 78 79 const char *signal_as_string(int signum) { return ::strsignal(signum); } 80 81 } // namespace testutils 82 } // namespace LIBC_NAMESPACE_DECL 83