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 2020 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/internal.h"
  #include "libc/calls/sig.internal.h"
  #include "libc/calls/struct/rusage.h"
  #include "libc/fmt/conv.h"
  #include "libc/intrin/spinlock.h"
  #include "libc/nt/accounting.h"
  #include "libc/nt/process.h"
  #include "libc/nt/runtime.h"
  #include "libc/nt/struct/iocounters.h"
  #include "libc/nt/struct/processmemorycounters.h"
  #include "libc/nt/thread.h"
  #include "libc/str/str.h"
  #include "libc/sysv/consts/rusage.h"
  #include "libc/sysv/errfuns.h"
  
  textwindows int sys_getrusage_nt(int who, struct rusage *usage) {
    int64_t me, nsignals;
    struct NtIoCounters iocount;
    struct NtProcessMemoryCountersEx memcount;
    struct NtFileTime ftExit, ftUser, ftKernel, ftCreation;
    if (!usage) return efault();
    if (who == 99) return enosys();  // @see libc/sysv/consts.sh
    if (!usage) return 0;
    me = GetCurrentProcess();
    if (!(who == RUSAGE_SELF ? GetProcessTimes : GetThreadTimes)(
            (who == RUSAGE_SELF ? GetCurrentProcess : GetCurrentThread)(),
            &ftCreation, &ftExit, &ftKernel, &ftUser) ||
        !GetProcessMemoryInfo(me, &memcount, sizeof(memcount)) ||
        !GetProcessIoCounters(me, &iocount)) {
      return __winerr();
    }
    _spinlock(&__sig_lock);
    nsignals = __sig_count;
    _spunlock(&__sig_lock);
    *usage = (struct rusage){
        .ru_utime = WindowsDurationToTimeVal(ReadFileTime(ftUser)),
        .ru_stime = WindowsDurationToTimeVal(ReadFileTime(ftKernel)),
        .ru_maxrss = memcount.PeakWorkingSetSize / 1024,
        .ru_majflt = memcount.PageFaultCount,
        .ru_inblock = iocount.ReadOperationCount,
        .ru_oublock = iocount.WriteOperationCount,
        .ru_nsignals = __sig_count,
    };
    return 0;
  }
  