/****************************************************************************
 * apps/testing/ostest/waitpid.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <assert.h>
#include <errno.h>
#include <sched.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h>
#include <sys/wait.h>
#include <unistd.h>

#include "ostest.h"

#ifdef CONFIG_SCHED_WAITPID

/****************************************************************************
 * Pre-processor Definitions
 ****************************************************************************/

#define RETURN_STATUS 14
#define NCHILDREN     3
#define PRIORITY      100

/****************************************************************************
 * Private Data
 ****************************************************************************/

static int g_waitpids[NCHILDREN];

/****************************************************************************
 * Private Functions
 ****************************************************************************/

static int waitpid_main(int argc, char *argv[])
{
  pid_t me = getpid();

  printf("waitpid_main: PID %d Started\n", me);
  sleep(3);
  printf("waitpid_main: PID %d exitting with result=%d\n",
          me, RETURN_STATUS);
  return RETURN_STATUS;
}

static void waitpid_start_children(void)
{
  int ret;
  int i;

  for (i = 0; i < NCHILDREN; i++)
    {
      ret = task_create("waitpid", PRIORITY, STACKSIZE, waitpid_main, NULL);
      if (ret < 0)
        {
          printf("waitpid_start_child: "
                 "ERROR Failed to start waitpid_main\n");
          ASSERT(false);
        }
      else
        {
          printf("waitpid_start_child: "
                 "Started waitpid_main at PID=%d\n", ret);
        }

      g_waitpids[i] = ret;
    }
}

static void waitpid_last(void)
{
  pid_t pid = -1;
  int stat_loc;
  int ret;
  int i;

  /* Find the last child thread that was started successfully */

  for (i = NCHILDREN - 1; i > 0; i--)
    {
      if (g_waitpids[i] >= 0)
        {
          pid = i;
          break;
        }
    }

  /* Is there any thread to wait for? */

  if (pid < 0)
    {
      printf("waitpid_last: ERROR: Nothing to wait for\n");
      ASSERT(false);
      return;
    }

  printf("waitpid_last: Waiting for PID=%d with waitpid()\n",
         g_waitpids[NCHILDREN - 1]);

  ret = waitpid(g_waitpids[NCHILDREN - 1], &stat_loc, 0);
  if (ret < 0)
    {
      int errcode = errno;

      /* Unfortunately, this main thread does not retain child status.
       * If child status is enabled (via CONFIG_SCHED_CHILD_STATUS),
       * ostest_main() disables the feature by calling sigactin with
       * SA_NOCLDWAIT.
       */

      if (errcode == ECHILD)
        {
          printf("waitpid_last: PASS: "
                 "PID %d waitpid failed with ECHILD.  That may be\n",
                 g_waitpids[NCHILDREN - 1]);
          printf("              acceptable "
                 "because child status is disabled on this thread.\n");
        }
      else
        {
          printf("waitpid_last: ERROR: PID %d waitpid failed: %d\n",
                 g_waitpids[NCHILDREN - 1], errcode);
          ASSERT(false);
        }
    }
  else if (WEXITSTATUS(stat_loc) != RETURN_STATUS)
    {
      printf("waitpid_last: ERROR: "
             "PID %d return status is %d, expected %d\n",
             g_waitpids[NCHILDREN - 1],
             WEXITSTATUS(stat_loc),
             RETURN_STATUS);
      ASSERT(false);
    }
  else
    {
      printf("waitpid_last: PASS: "
             "PID %d waitpid succeeded with stat_loc=%04x\n",
             g_waitpids[NCHILDREN - 1], stat_loc);
    }
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

int waitpid_test(void)
{
#ifdef CONFIG_SCHED_HAVE_PARENT
  siginfo_t info;
#endif
  int stat_loc;
  int ret;

  /* Start the children and wait for first one to complete */

  printf("\nTest waitpid()\n");
  waitpid_start_children();

  printf("waitpid_test: Waiting for PID=%d with waitpid()\n",
          g_waitpids[0]);
  ret = (int)waitpid(g_waitpids[0], &stat_loc, 0);
  if (ret < 0)
    {
      int errcode = errno;

      /* Unfortunately, this main thread does not retain child status.
       * If child status is enabled (via CONFIG_SCHED_CHILD_STATUS),
       * ostest_main() disables the feature by calling sigactin with
       * SA_NOCLDWAIT.
       */

      if (errcode == ECHILD)
        {
          printf("waitpid_test: PASS: "
                 "PID %d waitpid failed with ECHILD.  That may be\n",
                 g_waitpids[NCHILDREN - 1]);
          printf("              acceptable "
                 "because child status is disabled on this thread.\n");
        }
      else
        {
          printf("waitpid_test: ERROR: PID %d waitpid failed: %d\n",
                 g_waitpids[0], errcode);
          ASSERT(false);
        }
    }
  else if (ret != g_waitpids[0])
    {
      printf("waitpid_test: ERROR: PID %d wait returned PID %d\n",
             g_waitpids[0], ret);
      ASSERT(false);
    }
  else if (WEXITSTATUS(stat_loc) != RETURN_STATUS)
    {
      printf("waitpid_test: ERROR: "
             "PID %d return status is %d, expected %d\n",
             g_waitpids[0], WEXITSTATUS(stat_loc), RETURN_STATUS);
      ASSERT(false);
    }
  else
    {
      printf("waitpid_test: "
             "PID %d waitpid succeeded with stat_loc=%04x\n",
             g_waitpids[0], stat_loc);
    }

  /* Wait a bit to make sure that the other threads complete */

  waitpid_last();
  sleep(1);

#ifdef CONFIG_SCHED_HAVE_PARENT
  /* Start the children and wait for first one to complete */

  printf("\nTest waitid(P_PID)\n");
  waitpid_start_children();

  printf("waitpid_test: Waiting for PID=%d with waitid()\n", g_waitpids[0]);
  ret = waitid(P_PID, (id_t)g_waitpids[0], &info, WEXITED);
  if (ret < 0)
    {
      int errcode = errno;

      /* Unfortunately, this main thread does not retain child status.
       * If child status is enabled (via CONFIG_SCHED_CHILD_STATUS),
       * ostest_main() disables the feature by calling sigactin with
       * SA_NOCLDWAIT.
       */

      if (errcode == ECHILD)
        {
          printf("waitpid_test: PASS: "
                 "PID %d waitpid failed with ECHILD.  That may be\n",
                 g_waitpids[NCHILDREN - 1]);
          printf("              acceptable "
                 "because child status is disabled on this thread.\n");
        }
      else
        {
          printf("waitpid_test: ERROR: PID %d waitid failed: %d\n",
                 g_waitpids[0], errcode);
          ASSERT(false);
        }
    }
  else if (info.si_pid != g_waitpids[0])
    {
      printf("waitpid_test: ERROR: PID %d waitid returned PID %d\n",
             g_waitpids[0], info.si_pid);
      ASSERT(false);
    }
  else if (info.si_status != RETURN_STATUS)
    {
      printf("waitpid_test: ERROR: "
             "PID %d return status is %d, expected %d\n",
             info.si_pid, info.si_status, RETURN_STATUS);
      ASSERT(false);
    }
  else
    {
      printf("waitpid_test: waitid PID %d succeeded with si_status=%d\n",
             info.si_pid, info.si_status);
    }

  /* Wait a bit to make sure that the other threads complete */

  waitpid_last();
  sleep(1);

  /* Start the children and wait for any one to complete */

  printf("\nTest waitid(P_ALL)\n");
  waitpid_start_children();

  printf("waitpid_test: Waiting for any child with waitid()\n");
  ret = waitid(P_ALL, 0, &info, WEXITED);
  if (ret < 0)
    {
      int errcode = errno;

      /* Unfortunately, this main thread does not retain child status.
       * If child status is enabled (via CONFIG_SCHED_CHILD_STATUS),
       * ostest_main() disables the feature by calling sigactin with
       * SA_NOCLDWAIT.
       */

      if (errcode == ECHILD)
        {
          printf("waitpid_test: PASS: "
                 "PID %d waitpid failed with ECHILD.  That may be\n",
                 g_waitpids[NCHILDREN - 1]);
          printf("              acceptable "
                 "because child status is disabled on this thread.\n");
        }
      else
        {
          printf("waitpid_test: ERROR: waitid failed: %d\n", errcode);
          ASSERT(false);
        }
    }
  else if (info.si_status != RETURN_STATUS)
    {
      printf("waitpid_test: ERROR: "
             "PID %d return status is %d, expected %d\n",
             info.si_pid, info.si_status, RETURN_STATUS);
      ASSERT(false);
    }
  else
    {
      printf("waitpid_test: PID %d waitid succeeded with si_status=%d\n",
             info.si_pid, info.si_status);
    }

  /* Wait a bit to make sure that the other threads complete */

  waitpid_last();
  sleep(1);

  /* Start the children and wait for first one to complete */

  printf("\nTest wait()\n");
  waitpid_start_children();

  printf("waitpid_test: Waiting for any child with wait()\n");
  ret = (int)wait(&stat_loc);
  if (ret < 0)
    {
      int errcode = errno;

      /* Unfortunately, this main thread does not retain child status.
       * If child status is enabled (via CONFIG_SCHED_CHILD_STATUS),
       * ostest_main() disables the feature by calling sigactin with
       * SA_NOCLDWAIT.
       */

      if (errcode == ECHILD)
        {
          printf("waitpid_test: PASS: "
                 "PID %d waitpid failed with ECHILD.  That may be\n",
                 g_waitpids[NCHILDREN - 1]);
          printf("              acceptable "
                 "because child status is disabled on this thread.\n");
        }
      else
        {
          printf("waitpid_test: ERROR: wait failed: %d\n", errcode);
          ASSERT(false);
        }
    }
  else if (WEXITSTATUS(stat_loc) != RETURN_STATUS)
    {
      printf("waitpid_test: ERROR: "
             "PID %d return status is %d, expected %d\n",
             ret, WEXITSTATUS(stat_loc), RETURN_STATUS);
      ASSERT(false);
    }
  else
    {
      printf("waitpid_test: PID %d wait succeeded with stat_loc=%04x\n",
             ret, stat_loc);
    }

  /* Wait a bit to make sure that the other threads complete */

  waitpid_last();
  sleep(1);
#endif

  return 0;
}

#endif /* CONFIG_SCHED_WAITPID */