/*-*- 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 2020 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ This program is free software; you can redistribute it and/or modify         │
│ it under the terms of the GNU General Public License as published by         │
│ the Free Software Foundation; version 2 of the License.                      │
│                                                                              │
│ This program 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             │
│ General Public License for more details.                                     │
│                                                                              │
│ You should have received a copy of the GNU General Public License            │
│ along with this program; if not, write to the Free Software                  │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
│ 02110-1301 USA                                                               │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/calls/internal.h"
#include "libc/dce.h"
#include "libc/nt/nt/process.h"
#include "libc/nt/ntdll.h"
#include "libc/nt/process.h"
#include "libc/nt/runtime.h"
#include "libc/nt/struct/processbasicinformation.h"

static textwindows noinline int32_t getppid$nt(void) {
  struct NtProcessBasicInformation ProcessInformation;
  uint32_t gotsize = 0;
  if (!NtError(
          NtQueryInformationProcess(GetCurrentProcess(), 0, &ProcessInformation,
                                    sizeof(ProcessInformation), &gotsize)) &&
      gotsize >= sizeof(ProcessInformation) &&
      ProcessInformation.InheritedFromUniqueProcessId) {
    /* TODO(jart): Fix type mismatch and do we need to close this? */
    return ProcessInformation.InheritedFromUniqueProcessId;
  }
  return GetCurrentProcessId();
}

/**
 * Returns parent process id.
 * @asyncsignalsafe
 */
int32_t getppid(void) {
  if (!IsWindows()) {
    return getppid$sysv();
  } else {
    return getppid$nt();
  }
}