text: /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
  │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
  ╞══════════════════════════════════════════════════════════════════════════════╡
  │ Copyright 2021 Justine Alexandra Roberts Tunney                              │
  │                                                                              │
  │ Permission to use, copy, modify, and/or distribute this software for         │
  │ any purpose with or without fee is hereby granted, provided that the         │
  │ above copyright notice and this permission notice appear in all copies.      │
  │                                                                              │
  │ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
  │ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
  │ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
  │ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
  │ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
  │ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
  │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
  │ PERFORMANCE OF THIS SOFTWARE.                                                │
  ╚─────────────────────────────────────────────────────────────────────────────*/
  #include "libc/calls/calls.h"
  #include "libc/calls/sigbits.h"
  #include "libc/calls/struct/sigaction.h"
  #include "libc/dce.h"
  #include "libc/errno.h"
  #include "libc/runtime/runtime.h"
  #include "libc/sysv/consts/sa.h"
  #include "libc/sysv/consts/sig.h"
  #include "libc/testlib/testlib.h"
  
  bool gotsigint;
  
  void OnSigInt(int sig) {
    gotsigint = true;
  }
  
  TEST(sigaction, test) {
    /* TODO(jart): Why does RHEL5 behave differently? */
    /* TODO(jart): Windows needs huge signal overhaul */
    if (IsWindows()) return;
    int pid, status;
    sigset_t block, ignore, oldmask;
    struct sigaction saint = {.sa_handler = OnSigInt};
    sigemptyset(&block);
    sigaddset(&block, SIGINT);
    EXPECT_NE(-1, sigprocmask(SIG_BLOCK, &block, &oldmask));
    sigfillset(&ignore);
    sigdelset(&ignore, SIGINT);
    EXPECT_NE(-1, sigaction(SIGINT, &saint, NULL));
    ASSERT_NE(-1, (pid = fork()));
    if (!pid) {
      EXPECT_NE(-1, kill(getppid(), SIGINT));
      EXPECT_EQ(-1, sigsuspend(&ignore));
      EXPECT_EQ(EINTR, errno);
      EXPECT_TRUE(gotsigint);
      _exit(0);
    }
    EXPECT_EQ(-1, sigsuspend(&ignore));
    EXPECT_NE(-1, kill(pid, SIGINT));
    EXPECT_NE(-1, waitpid(pid, &status, 0));
    EXPECT_EQ(1, WIFEXITED(status));
    EXPECT_EQ(0, WEXITSTATUS(status));
    EXPECT_EQ(0, WTERMSIG(status));
    EXPECT_NE(-1, sigprocmask(SIG_BLOCK, &oldmask, NULL));
  }
  