/* Basic tests for stat, lstat, fstat, and fstatat.
   Copyright (C) 2021-2026 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
   <https://www.gnu.org/licenses/>.  */

#include <array_length.h>
#include <errno.h>
#include <fcntl.h>
#include <support/check.h>
#include <support/support.h>
#include <support/temp_file.h>
#include <support/xunistd.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

static void
stat_check (int fd, const char *path, struct stat *st)
{
  TEST_COMPARE (stat (path, st), 0);
}

static void
lstat_check (int fd, const char *path, struct stat *st)
{
  TEST_COMPARE (lstat (path, st), 0);
}

static void
fstat_check (int fd, const char *path, struct stat *st)
{
  /* Test for invalid fstat input (BZ #27559).  */
  TEST_COMPARE (fstat (AT_FDCWD, st), -1);
  TEST_COMPARE (errno, EBADF);

  TEST_COMPARE (fstat (fd, st), 0);
}

static void
fstatat_check (int fd, const char *path, struct stat *st)
{
  TEST_COMPARE (fstatat (fd, "", st, 0), -1);
  TEST_COMPARE (errno, ENOENT);

  TEST_COMPARE (fstatat (AT_FDCWD, "_non_existing_file", st, 0), -1);
  TEST_COMPARE (errno, ENOENT);

  TEST_COMPARE (fstatat (fd, path, st, 0), 0);
}

static void
fstatat_link (const char *path, struct stat *st)
{
  TEST_COMPARE (fstatat (AT_FDCWD, path, st, 0), -1);
  TEST_COMPARE (errno, ENOENT);

  TEST_COMPARE (fstatat (AT_FDCWD, path, st, AT_SYMLINK_NOFOLLOW), 0);
  TEST_COMPARE (!S_ISLNK(st->st_mode), 0);
}

typedef void (*test_t)(int, const char *path, struct stat *);

static int
do_test (void)
{
  char *path;
  char *tempdir = support_create_temp_directory ("tst-stat-");
  char *linkname = xasprintf ("%s/tst-fstat.linkname", tempdir);
  int fd = create_temp_file ("tst-fstat.", &path);
  TEST_VERIFY_EXIT (fd >= 0);
  support_write_file_string (path, "abc");

  /* This should help to prevent delayed allocation, which may result
     in a spurious stx_blocks/st_blocks difference.  */
  fsync (fd);

  bool check_ns = support_stat_nanoseconds (path);
  if (!check_ns)
    printf ("warning: timestamp with nanoseconds not supported\n");

  struct statx stx;
  struct stat st;
  TEST_COMPARE (statx (fd, path, 0, STATX_BASIC_STATS, &stx), 0);

  test_t tests[] = { stat_check, lstat_check, fstat_check, fstatat_check };

  for (int i = 0; i < array_length (tests); i++)
    {
      tests[i](fd, path, &st);

      TEST_COMPARE (stx.stx_dev_major, major (st.st_dev));
      TEST_COMPARE (stx.stx_dev_minor, minor (st.st_dev));
      TEST_COMPARE (stx.stx_ino, st.st_ino);
      TEST_COMPARE (stx.stx_mode, st.st_mode);
      TEST_COMPARE (stx.stx_nlink, st.st_nlink);
      TEST_COMPARE (stx.stx_uid, st.st_uid);
      TEST_COMPARE (stx.stx_gid, st.st_gid);
      TEST_COMPARE (stx.stx_rdev_major, major (st.st_rdev));
      TEST_COMPARE (stx.stx_rdev_minor, minor (st.st_rdev));
      TEST_COMPARE (stx.stx_blksize, st.st_blksize);
      TEST_COMPARE (stx.stx_blocks, st.st_blocks);

      TEST_COMPARE (stx.stx_ctime.tv_sec, st.st_ctim.tv_sec);
      TEST_COMPARE (stx.stx_mtime.tv_sec, st.st_mtim.tv_sec);
      if (check_ns)
	{
	  TEST_COMPARE (stx.stx_ctime.tv_nsec, st.st_ctim.tv_nsec);
	  TEST_COMPARE (stx.stx_mtime.tv_nsec, st.st_mtim.tv_nsec);
	}
    }

  TEST_COMPARE (symlink ("tst-fstat.target", linkname), 0);
  add_temp_file (linkname);
  fstatat_link (linkname, &st);

  free (linkname);
  free (tempdir);

  return 0;
}

#include <support/test-driver.c>
