diff options
Diffstat (limited to 'm4/symlinkat.m4')
| -rw-r--r-- | m4/symlinkat.m4 | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/m4/symlinkat.m4 b/m4/symlinkat.m4 new file mode 100644 index 0000000..4d7b823 --- /dev/null +++ b/m4/symlinkat.m4 @@ -0,0 +1,56 @@ +# serial 10 +# See if we need to provide symlinkat replacement. + +dnl Copyright (C) 2009-2022 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +# Written by Eric Blake. + +AC_DEFUN([gl_FUNC_SYMLINKAT], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + AC_REQUIRE([gl_FUNC_OPENAT]) + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CHECK_FUNCS_ONCE([symlinkat]) + if test $ac_cv_func_symlinkat = no; then + HAVE_SYMLINKAT=0 + else + AC_CACHE_CHECK([whether symlinkat handles trailing slash correctly], + [gl_cv_func_symlinkat_works], + [AC_RUN_IFELSE( + [AC_LANG_PROGRAM( + [[#include <fcntl.h> + #include <unistd.h> + ]], + [[int result = 0; + if (!symlinkat ("a", AT_FDCWD, "conftest.link/")) + result |= 1; + if (symlinkat ("conftest.f", AT_FDCWD, "conftest.lnk2")) + result |= 2; + else if (!symlinkat ("a", AT_FDCWD, "conftest.lnk2/")) + result |= 4; + return result; + ]])], + [gl_cv_func_symlinkat_works=yes], + [gl_cv_func_symlinkat_works=no], + [case "$host_os" in + # Guess yes on Linux systems. + linux-* | linux) gl_cv_func_symlinkat_works="guessing yes" ;; + # Guess yes on glibc systems. + *-gnu* | gnu*) gl_cv_func_symlinkat_works="guessing yes" ;; + # If we don't know, obey --enable-cross-guesses. + *) gl_cv_func_symlinkat_works="$gl_cross_guess_normal" ;; + esac + ]) + rm -f conftest.f conftest.link conftest.lnk2]) + case "$gl_cv_func_symlinkat_works" in + *yes) ;; + *) + REPLACE_SYMLINKAT=1 + ;; + esac + fi +]) |