1# serial 32
2
3# Copyright (C) 1997-2001, 2003-2019 Free Software Foundation, Inc.
4#
5# This file is free software; the Free Software Foundation
6# gives unlimited permission to copy and/or distribute it,
7# with or without modifications, as long as this notice is preserved.
8
9dnl From Jim Meyering.
10
11AC_DEFUN([gl_FUNC_LSTAT],
12[
13  AC_REQUIRE([AC_CANONICAL_HOST])
14  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
15  dnl If lstat does not exist, the replacement <sys/stat.h> does
16  dnl "#define lstat stat", and lstat.c is a no-op.
17  AC_CHECK_FUNCS_ONCE([lstat])
18  if test $ac_cv_func_lstat = yes; then
19    AC_REQUIRE([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
20    case $host_os,$gl_cv_func_lstat_dereferences_slashed_symlink in
21      solaris* | *no)
22        REPLACE_LSTAT=1
23        ;;
24    esac
25  else
26    HAVE_LSTAT=0
27  fi
28])
29
30# Prerequisites of lib/lstat.c.
31AC_DEFUN([gl_PREREQ_LSTAT], [:])
32
33AC_DEFUN([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK],
34[
35  dnl We don't use AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK any more, because it
36  dnl is no longer maintained in Autoconf and because it invokes AC_LIBOBJ.
37  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
38  AC_CACHE_CHECK([whether lstat correctly handles trailing slash],
39    [gl_cv_func_lstat_dereferences_slashed_symlink],
40    [rm -f conftest.sym conftest.file
41     echo >conftest.file
42     AC_RUN_IFELSE(
43       [AC_LANG_PROGRAM(
44          [AC_INCLUDES_DEFAULT],
45          [[struct stat sbuf;
46            if (symlink ("conftest.file", "conftest.sym") != 0)
47              return 1;
48            /* Linux will dereference the symlink and fail, as required by
49               POSIX.  That is better in the sense that it means we will not
50               have to compile and use the lstat wrapper.  */
51            return lstat ("conftest.sym/", &sbuf) == 0;
52          ]])],
53       [gl_cv_func_lstat_dereferences_slashed_symlink=yes],
54       [gl_cv_func_lstat_dereferences_slashed_symlink=no],
55       [case "$host_os" in
56          linux-* | linux)
57            # Guess yes on Linux systems.
58            gl_cv_func_lstat_dereferences_slashed_symlink="guessing yes" ;;
59          *-gnu* | gnu*)
60            # Guess yes on glibc systems.
61            gl_cv_func_lstat_dereferences_slashed_symlink="guessing yes" ;;
62          mingw*)
63            # Guess no on native Windows.
64            gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
65          *)
66            # If we don't know, assume the worst.
67            gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
68        esac
69       ])
70     rm -f conftest.sym conftest.file
71    ])
72  case "$gl_cv_func_lstat_dereferences_slashed_symlink" in
73    *yes)
74      AC_DEFINE_UNQUOTED([LSTAT_FOLLOWS_SLASHED_SYMLINK], [1],
75        [Define to 1 if 'lstat' dereferences a symlink specified
76         with a trailing slash.])
77      ;;
78  esac
79])
80