libc/test/UnitTest/ExecuteFunctionUnix.cpp

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