cosmopolitan/libc/calls/mkdirat-nt.c

/*-*- 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/internal.h"
#include "libc/errno.h"
#include "libc/nt/enum/fileflagandattributes.h"
#include "libc/nt/files.h"
#include "libc/nt/runtime.h"
#include "libc/str/str.h"

static textwindows bool SubpathExistsThatsNotDirectory(char16_t *path) {
  int e;
  char16_t *p;
  uint32_t attrs;
  e = errno;
  while ((p = strrchr16(path, '\\'))) {
    *p = u'\0';
    if ((attrs = GetFileAttributes(path)) != -1u) {
      if (attrs & kNtFileAttributeDirectory) {
        return false;
      } else {
        return true;
      }
    } else {
      errno = e;
    }
  }
  return false;
}

textwindows int sys_mkdirat_nt(int dirfd, const char *path, uint32_t mode) {
  int e;
  char16_t *p, path16[PATH_MAX];
  if (__mkntpathat(dirfd, path, 0, path16) == -1) return -1;
  if (CreateDirectory(path16, 0)) return 0;

  // WIN32 doesn't distinguish between ENOTDIR and ENOENT
  //
  // - ENOTDIR: A component used as a directory in pathname is not, in
  //   fact, a directory. -or- pathname is relative and dirfd is a file
  //   descriptor referring to a file other than a directory.
  //
  // - ENOENT: A directory component in pathname does not exist or is a
  //   dangling symbolic link.
  if (errno == ENOTDIR) {
    if (!SubpathExistsThatsNotDirectory(path16)) {
      errno = ENOENT;
    }
  }
  return -1;
}