view m4/dirent_h.m4 @ 15308:a3ba680ad389

strerror_r: fix OpenBSD behavior on 0 OpenBSD treats strerror_r(0,,) as a success, but with a message "Undefined error: 0"; while this is distinct from strerror_r(-1,,) returning "Unknown error: -1", it does not imply success. Meanwhile, if buf is short enough for ERANGE, then we can't use strstr to look for "Unknown" or "Undefined" in the resulting message, like we had been doing for strerror(). Fix this by shifting the burden - now the strerror-override code guarantees that 0 will have an override when needed. * lib/strerror-override.c (strerror_override): Also override 0 when needed. * lib/strerror-override.h (strerror_override): Likewise. * lib/strerror.c (strerror): Simplify, now that 0 override is done earlier. * lib/strerror_r.c (strerror_r): Likewise. * m4/strerror.m4 (gl_FUNC_STRERROR): Split detection of 0 behavior... (gl_FUNC_STRERROR_0): ...into new macro. * m4/strerror_r.m4 (gl_FUNC_STRERROR_R): Replace strerror_r if 0 is overridden. (gl_FUNC_STRERROR_R_WORKS): Avoid extra tests if 0 is broken. * modules/strerror-override (Files): Add strerror.m4. (configure.ac): Also provide override for 0 when needed. * doc/posix-functions/strerror.texi (strerror): Document this. * doc/posix-functions/perror.texi (perror): Likewise. Signed-off-by: Eric Blake <eblake@redhat.com>
author Eric Blake <eblake@redhat.com>
date Tue, 21 Jun 2011 08:50:51 -0600
parents f7f11056a86e
children 550b8b7d6140
line wrap: on
line source

# dirent_h.m4 serial 14
dnl Copyright (C) 2008-2011 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.

dnl Written by Bruno Haible.

AC_DEFUN([gl_DIRENT_H],
[
  dnl Use AC_REQUIRE here, so that the default behavior below is expanded
  dnl once only, before all statements that occur in other macros.
  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])

  dnl <dirent.h> is always overridden, because of GNULIB_POSIXCHECK.
  gl_CHECK_NEXT_HEADERS([dirent.h])

  dnl Check for declarations of anything we want to poison if the
  dnl corresponding gnulib module is not in use.
  gl_WARN_ON_USE_PREPARE([[#include <dirent.h>
    ]], [alphasort dirfd fdopendir scandir])
])

AC_DEFUN([gl_DIRENT_MODULE_INDICATOR],
[
  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
  dnl Define it also as a C macro, for the benefit of the unit tests.
  gl_MODULE_INDICATOR_FOR_TESTS([$1])
])

AC_DEFUN([gl_DIRENT_H_DEFAULTS],
[
  AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) dnl for REPLACE_FCHDIR
  GNULIB_DIRFD=0;       AC_SUBST([GNULIB_DIRFD])
  GNULIB_FDOPENDIR=0;   AC_SUBST([GNULIB_FDOPENDIR])
  GNULIB_SCANDIR=0;     AC_SUBST([GNULIB_SCANDIR])
  GNULIB_ALPHASORT=0;   AC_SUBST([GNULIB_ALPHASORT])
  dnl Assume proper GNU behavior unless another module says otherwise.
  HAVE_DECL_DIRFD=1;    AC_SUBST([HAVE_DECL_DIRFD])
  HAVE_DECL_FDOPENDIR=1;AC_SUBST([HAVE_DECL_FDOPENDIR])
  HAVE_FDOPENDIR=1;     AC_SUBST([HAVE_FDOPENDIR])
  HAVE_SCANDIR=1;       AC_SUBST([HAVE_SCANDIR])
  HAVE_ALPHASORT=1;     AC_SUBST([HAVE_ALPHASORT])
  REPLACE_CLOSEDIR=0;   AC_SUBST([REPLACE_CLOSEDIR])
  REPLACE_DIRFD=0;      AC_SUBST([REPLACE_DIRFD])
  REPLACE_FDOPENDIR=0;  AC_SUBST([REPLACE_FDOPENDIR])
  REPLACE_OPENDIR=0;    AC_SUBST([REPLACE_OPENDIR])
])