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 "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