/* Testcase checks, if setcontext(), swapcontext() restores signal-mask

   and if pending signals are delivered after those calls.

   Copyright (C) 2015-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <stdio.h>

#include <stdlib.h>

#include <sys/types.h>

#include <signal.h>

#include <ucontext.h>

#include <unistd.h>

volatile int global;

volatile sig_atomic_t handlerCalled;

static void

check (const char *funcName)

{

  sigset_t set;

  /* check if SIGUSR2 is unblocked after setcontext-call.  */

  sigprocmask (SIG_BLOCK, NULL, &set);

  if (sigismember (&set, SIGUSR2) != 0)

    {

      printf ("FAIL: SIGUSR2 is blocked after %s.\n", funcName);

      exit (1);

    }

  if (sigismember (&set, SIGUSR1) != 1)

    {

      printf ("FAIL: SIGUSR1 is not blocked after %s.\n", funcName);

      exit (1);

    }

}

static void

signalmask (int how, int signum)

{

  sigset_t set;

  sigemptyset (&set);

  sigaddset (&set, signum);

  if (sigprocmask (how, &set, NULL) != 0)

    {

      printf ("FAIL: sigprocmaks (%d, %d, NULL): %m\n", how, signum);

      exit (1);

    }

}

static void

signalpending (int signum, const char *msg)

{

  sigset_t set;

  sigemptyset (&set);

  if (sigpending (&set) != 0)

    {

      printf ("FAIL: sigpending: %m\n");

      exit (1);

    }

  if (sigismember (&set, SIGUSR2) != 1)

    {

      printf ("FAIL: Signal %d is not pending %s\n", signum, msg);

      exit (1);

    }

}

static void

handler (int __attribute__ ((unused)) signum)

{

  handlerCalled ++;

}

static int

do_test (void)

{

  ucontext_t ctx, oldctx;

  struct sigaction action;

  pid_t pid;

  pid = getpid ();

  /* unblock SIGUSR2 */

  signalmask (SIG_UNBLOCK, SIGUSR2);

  /* block SIGUSR1 */

  signalmask (SIG_BLOCK, SIGUSR1);

  /* register handler for SIGUSR2  */

  action.sa_flags = 0;

  action.sa_handler = handler;

  sigemptyset (&action.sa_mask);

  sigaction (SIGUSR2, &action, NULL);

  if (getcontext (&ctx) != 0)

    {

      printf ("FAIL: getcontext: %m\n");

      exit (1);

    }

  global++;

  if (global == 1)

    {

      puts ("after getcontext");

      /* block SIGUSR2  */

      signalmask (SIG_BLOCK, SIGUSR2);

      /* send SIGUSR2 to me  */

      handlerCalled = 0;

      kill (pid, SIGUSR2);

      /* was SIGUSR2 handler called?  */

      if (handlerCalled != 0)

	{

	  puts ("FAIL: signal handler was called, but signal was blocked.");

	  exit (1);

	}

      /* is SIGUSR2 pending?  */

      signalpending (SIGUSR2, "before setcontext");

      /* SIGUSR2 will be unblocked by setcontext-call.  */

      if (setcontext (&ctx) != 0)

	{

	  printf ("FAIL: setcontext: %m\n");

	  exit (1);

	}

    }

  else if (global == 2)

    {

      puts ("after setcontext");

      /* check SIGUSR1/2  */

      check ("setcontext");

      /* was SIGUSR2 handler called? */

      if (handlerCalled != 1)

	{

	  puts ("FAIL: signal handler was not called after setcontext.");

	  exit (1);

	}

      /* block SIGUSR2 */

      signalmask (SIG_BLOCK, SIGUSR2);

      /* send SIGUSR2 to me  */

      handlerCalled = 0;

      kill (pid, SIGUSR2);

      /* was SIGUSR2 handler called?  */

      if (handlerCalled != 0)

	{

	  puts ("FAIL: signal handler was called, but signal was blocked.");

	  exit (1);

	}

      /* is SIGUSR2 pending?  */

      signalpending (SIGUSR2, "before swapcontext");

      if (swapcontext (&oldctx, &ctx) != 0)

	{

	  printf ("FAIL: swapcontext: %m\n");

	  exit (1);

	}

      puts ("after returned from swapcontext");

      if (global != 3)

	{

	  puts ("FAIL: returned from swapcontext without ctx-context called.");

	  exit (1);

	}

      puts ("test succeeded");

      return 0;

    }

  else if ( global != 3 )

    {

      puts ("FAIL: 'global' not incremented three times");

      exit (1);

    }

  puts ("after swapcontext");

  /* check SIGUSR1/2  */

  check ("swapcontext");

  /* was SIGUSR2 handler called? */

  if (handlerCalled != 1)

    {

      puts ("FAIL: signal handler was not called after swapcontext.");

      exit (1);

    }

  /* check sigmask in old context of swapcontext-call  */

  if (sigismember (&oldctx.uc_sigmask, SIGUSR2) != 1)

    {

      puts ("FAIL: SIGUSR2 is not blocked in oldctx.uc_sigmask.");

      exit (1);

    }

  if (sigismember (&oldctx.uc_sigmask, SIGUSR1) != 1)

    {

      puts ("FAIL: SIGUSR1 is not blocked in oldctx.uc_sigmaks.");

      exit (1);

    }

  /* change to old context, which was gathered by swapcontext() call.  */

  setcontext (&oldctx);

  puts ("FAIL: returned from setcontext (&oldctx)");

  exit (1);

}

#define TEST_FUNCTION do_test ()

#include "../test-skeleton.c"