Adding upstream version 9.1.upstream/9.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 705 insertions, 0 deletions

diff --git a/gnulib-tests/init.sh b/gnulib-tests/init.sh
new file mode 100644
index 0000000..d5d37c9
--- /dev/null
+++ b/gnulib-tests/init.sh
@@ -0,0 +1,705 @@
+# source this file; set up for tests
+
+# Copyright (C) 2009-2022 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+# Using this file in a test
+# =========================
+#
+# The typical skeleton of a test looks like this:
+#
+#   #!/bin/sh
+#   . "${srcdir=.}/init.sh"; path_prepend_ .
+#   Execute some commands.
+#   Note that these commands are executed in a subdirectory, therefore you
+#   need to prepend "../" to relative filenames in the build directory.
+#   Note that the "path_prepend_ ." is useful only if the body of your
+#   test invokes programs residing in the initial directory.
+#   For example, if the programs you want to test are in src/, and this test
+#   script is named tests/test-1, then you would use "path_prepend_ ../src",
+#   or perhaps export PATH='$(abs_top_builddir)/src$(PATH_SEPARATOR)'"$$PATH"
+#   to all tests via automake's TESTS_ENVIRONMENT.
+#   Set the exit code 0 for success, 77 for skipped, or 1 or other for failure.
+#   Use the skip_ and fail_ functions to print a diagnostic and then exit
+#   with the corresponding exit code.
+#   Exit $?
+
+# Executing a test that uses this file
+# ====================================
+#
+# Running a single test:
+#   $ make check TESTS=test-foo.sh
+#
+# Running a single test, with verbose output:
+#   $ make check TESTS=test-foo.sh VERBOSE=yes
+#
+# Running a single test, keeping the temporary directory:
+#   $ make check TESTS=test-foo.sh KEEP=yes
+#
+# Running a single test, with single-stepping:
+#   1. Go into a sub-shell:
+#   $ bash
+#   2. Set relevant environment variables from TESTS_ENVIRONMENT in the
+#      Makefile:
+#   $ export srcdir=../../tests # this is an example
+#   3. Execute the commands from the test, copy&pasting them one by one:
+#   $ . "$srcdir/init.sh"; path_prepend_ .
+#   ...
+#   4. Finally
+#   $ exit
+
+# =============================================================================
+# Elementary diagnostics
+
+ME_=`expr "./$0" : '.*/\(.*\)$'`
+
+# Prepare PATH_SEPARATOR.
+# The user is always right.
+if test "${PATH_SEPARATOR+set}" != set; then
+  # Determine PATH_SEPARATOR by trying to find /bin/sh in a PATH which
+  # contains only /bin. Note that ksh looks also at the FPATH variable,
+  # so we have to set that as well for the test.
+  PATH_SEPARATOR=:
+  (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+    && { (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+           || PATH_SEPARATOR=';'
+       }
+fi
+
+# We use a trap below for cleanup.  This requires us to go through
+# hoops to get the right exit status transported through the handler.
+# So use 'Exit STATUS' instead of 'exit STATUS' inside of the tests.
+# Turn off errexit here so that we don't trip the bug with OSF1/Tru64
+# sh inside this function.
+Exit () { set +e; (exit $1); exit $1; }
+
+# Print warnings (e.g., about skipped and failed tests) to this file number.
+# Override by defining to say, 9, in init.cfg, and putting say,
+#   export ...ENVVAR_SETTINGS...; $(SHELL) 9>&2
+# in the definition of TESTS_ENVIRONMENT in your tests/Makefile.am file.
+# This is useful when using automake's parallel tests mode, to print
+# the reason for skip/failure to console, rather than to the .log files.
+: ${stderr_fileno_=2}
+
+# Note that correct expansion of "$*" depends on IFS starting with ' '.
+# Always write the full diagnostic to stderr.
+# When stderr_fileno_ is not 2, also emit the first line of the
+# diagnostic to that file descriptor.
+warn_ ()
+{
+  # If IFS does not start with ' ', set it and emit the warning in a subshell.
+  case $IFS in
+    ' '*) printf '%s\n' "$*" >&2
+          test $stderr_fileno_ = 2 \
+            || { printf '%s\n' "$*" | sed 1q >&$stderr_fileno_ ; } ;;
+    *) (IFS=' '; warn_ "$@");;
+  esac
+}
+fail_ () { warn_ "$ME_: failed test: $@"; Exit 1; }
+skip_ () { warn_ "$ME_: skipped test: $@"; Exit 77; }
+fatal_ () { warn_ "$ME_: hard error: $@"; Exit 99; }
+framework_failure_ () { warn_ "$ME_: set-up failure: $@"; Exit 99; }
+
+# =============================================================================
+# Ensure the shell supports modern syntax.
+
+# Sanitize this shell to POSIX mode, if possible.
+DUALCASE=1; export DUALCASE
+if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then
+  emulate sh
+  NULLCMD=:
+  alias -g '${1+"$@"}'='"$@"'
+  setopt NO_GLOB_SUBST
+else
+  case `(set -o) 2>/dev/null` in
+    *posix*) set -o posix ;;
+  esac
+fi
+
+# We require $(...) support unconditionally.
+# We require that the printf built-in work correctly regarding octal escapes;
+# this eliminates /bin/sh on AIX 7.2.
+# We require non-surprising "local" semantics (this eliminates dash).
+# This takes the admittedly draconian step of eliminating dash, because the
+# assignment tab=$(printf '\t') works fine, yet preceding it with "local "
+# transforms it into an assignment that sets the variable to the empty string.
+# That is too counter-intuitive, and can lead to subtle run-time malfunction.
+# The example below is less subtle in that with dash, it evokes the run-time
+# exception "dash: 1: local: 1: bad variable name".
+# We require a few additional shell features only when $EXEEXT is nonempty,
+# in order to support automatic $EXEEXT emulation:
+# - hyphen-containing alias names
+# - we prefer to use ${var#...} substitution, rather than having
+#   to work around lack of support for that feature.
+# The following code attempts to find a shell with support for these features.
+# If the current shell passes the test, we're done.  Otherwise, test other
+# shells until we find one that passes.  If one is found, re-exec it.
+# If no acceptable shell is found, skip the current test.
+#
+# The "...set -x; P=1 true 2>err..." test is to disqualify any shell that
+# emits "P=1" into err, as /bin/sh from SunOS 5.11 and OpenBSD 4.7 do.
+#
+# Use "9" to indicate success (rather than 0), in case some shell acts
+# like Solaris 10's /bin/sh but exits successfully instead of with status 2.
+
+# Eval this code in a subshell to determine a shell's suitability.
+# 10 - passes all tests; ok to use
+#  9 - ok, but enabling "set -x" corrupts app stderr; prefer higher score
+#  ? - not ok
+gl_shell_test_script_='
+test $(echo y) = y || exit 1
+LC_ALL=en_US.UTF-8 printf "\\351" 2>/dev/null \
+  | LC_ALL=C tr "\\351" x | LC_ALL=C grep "^x$" > /dev/null \
+  || exit 1
+printf "\\351" 2>/dev/null \
+  | LC_ALL=C tr "\\351" x | LC_ALL=C grep "^x$" > /dev/null \
+  || exit 1
+f_local_() { local v=1; }; f_local_ || exit 1
+f_dash_local_fail_() { local t=$(printf " 1"); }; f_dash_local_fail_
+score_=10
+if test "$VERBOSE" = yes; then
+  test -n "$( (exec 3>&1; set -x; P=1 true 2>&3) 2> /dev/null)" && score_=9
+fi
+test -z "$EXEEXT" && exit $score_
+shopt -s expand_aliases
+alias a-b="echo zoo"
+v=abx
+     test ${v%x} = ab \
+  && test ${v#a} = bx \
+  && test $(a-b) = zoo \
+  && exit $score_
+'
+
+if test "x$1" = "x--no-reexec"; then
+  shift
+else
+  # Assume a working shell.  Export to subshells (setup_ needs this).
+  gl_set_x_corrupts_stderr_=false
+  export gl_set_x_corrupts_stderr_
+
+  # Record the first marginally acceptable shell.
+  marginal_=
+
+  # Search for a shell that meets our requirements.
+  for re_shell_ in __current__ "${CONFIG_SHELL:-no_shell}" \
+      /bin/sh bash dash zsh pdksh fail
+  do
+    test "$re_shell_" = no_shell && continue
+
+    # If we've made it all the way to the sentinel, "fail" without
+    # finding even a marginal shell, skip this test.
+    if test "$re_shell_" = fail; then
+      test -z "$marginal_" && skip_ failed to find an adequate shell
+      re_shell_=$marginal_
+      break
+    fi
+
+    # When testing the current shell, simply "eval" the test code.
+    # Otherwise, run it via $re_shell_ -c ...
+    if test "$re_shell_" = __current__; then
+      # 'eval'ing this code makes Solaris 10's /bin/sh exit with
+      # $? set to 2.  It does not evaluate any of the code after the
+      # "unexpected" first '('.  Thus, we must run it in a subshell.
+      ( eval "$gl_shell_test_script_" ) > /dev/null 2>&1
+    else
+      "$re_shell_" -c "$gl_shell_test_script_" 2>/dev/null
+    fi
+
+    st_=$?
+
+    # $re_shell_ works just fine.  Use it.
+    if test $st_ = 10; then
+      gl_set_x_corrupts_stderr_=false
+      break
+    fi
+
+    # If this is our first marginally acceptable shell, remember it.
+    if test "$st_:$marginal_" = 9: ; then
+      marginal_="$re_shell_"
+      gl_set_x_corrupts_stderr_=true
+    fi
+  done
+
+  if test "$re_shell_" != __current__; then
+    # Found a usable shell.  Preserve -v and -x.
+    case $- in
+      *v*x* | *x*v*) opts_=-vx ;;
+      *v*) opts_=-v ;;
+      *x*) opts_=-x ;;
+      *) opts_= ;;
+    esac
+    re_shell=$re_shell_
+    export re_shell
+    exec "$re_shell_" $opts_ "$0" --no-reexec "$@"
+    echo "$ME_: exec failed" 1>&2
+    exit 127
+  fi
+fi
+
+# =============================================================================
+# Ensure the shell behaves reasonably.
+
+# If this is bash, turn off all aliases.
+test -n "$BASH_VERSION" && unalias -a
+
+# Note that when supporting $EXEEXT (transparently mapping from PROG_NAME to
+# PROG_NAME.exe), we want to support hyphen-containing names like test-acos.
+# That is part of the shell-selection test above.  Why use aliases rather
+# than functions?  Because support for hyphen-containing aliases is more
+# widespread than that for hyphen-containing function names.
+test -n "$EXEEXT" && test -n "$BASH_VERSION" && shopt -s expand_aliases
+
+# =============================================================================
+# Creating a temporary directory (needed by the core test framework)
+
+# Create a temporary directory, much like mktemp -d does.
+# Written by Jim Meyering.
+#
+# Usage: mktempd_ /tmp phoey.XXXXXXXXXX
+#
+# First, try to use the mktemp program.
+# Failing that, we'll roll our own mktemp-like function:
+#  - try to get random bytes from /dev/urandom, mapping them to file-name bytes
+#  - failing that, generate output from a combination of quickly-varying
+#      sources and awk.
+#  - try to create the desired directory.
+#  - make only $MAX_TRIES_ attempts
+
+# Helper function.  Print $N pseudo-random bytes from a-zA-Z0-9.
+rand_bytes_ ()
+{
+  n_=$1
+
+  # Maybe try openssl rand -base64 $n_prime_|tr '+/=\012' abcd first?
+  # But if they have openssl, they probably have mktemp, too.
+
+  chars_=abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789
+  dev_rand_=/dev/urandom
+  if test -r "$dev_rand_"; then
+    # Note: 256-length($chars_) == 194; 3 copies of $chars_ is 186 + 8 = 194.
+    dd ibs=$n_ count=1 if=$dev_rand_ 2>/dev/null \
+      | LC_ALL=C tr -c $chars_ 01234567$chars_$chars_$chars_
+    return
+  fi
+
+  # Fall back on quickly-varying sources + awk.
+  # Limit awk program to 7th Edition Unix so that it works even on Solaris 10.
+
+  (date; date +%N; free; who -a; w; ps auxww; ps -ef) 2>&1 | awk '
+     BEGIN {
+       n = '"$n_"'
+       for (i = 0; i < 256; i++)
+         ordinal[sprintf ("%c", i)] = i
+     }
+     {
+       for (i = 1; i <= length; i++)
+         a[ai++ % n] += ordinal[substr ($0, i, 1)]
+     }
+     END {
+       chars = "'"$chars_"'"
+       charslen = length (chars)
+       for (i = 0; i < n; i++)
+         printf "%s", substr (chars, a[i] % charslen + 1, 1)
+       printf "\n"
+     }
+  '
+}
+
+mktempd_ ()
+{
+  case $# in
+  2);;
+  *) fail_ "Usage: mktempd_ DIR TEMPLATE";;
+  esac
+
+  destdir_=$1
+  template_=$2
+
+  MAX_TRIES_=4
+
+  # Disallow any trailing slash on specified destdir:
+  # it would subvert the post-mktemp "case"-based destdir test.
+  case $destdir_ in
+  / | //) destdir_slash_=$destdir;;
+  */) fail_ "invalid destination dir: remove trailing slash(es)";;
+  *) destdir_slash_=$destdir_/;;
+  esac
+
+  case $template_ in
+  *XXXX) ;;
+  *) fail_ \
+       "invalid template: $template_ (must have a suffix of at least 4 X's)";;
+  esac
+
+  # First, try to use mktemp.
+  d=`unset TMPDIR; { mktemp -d -t -p "$destdir_" "$template_"; } 2>/dev/null` &&
+
+  # The resulting name must be in the specified directory.
+  case $d in "$destdir_slash_"*) :;; *) false;; esac &&
+
+  # It must have created the directory.
+  test -d "$d" &&
+
+  # It must have 0700 permissions.  Handle sticky "S" bits.
+  perms=`ls -dgo "$d" 2>/dev/null` &&
+  case $perms in drwx--[-S]---*) :;; *) false;; esac && {
+    echo "$d"
+    return
+  }
+
+  # If we reach this point, we'll have to create a directory manually.
+
+  # Get a copy of the template without its suffix of X's.
+  base_template_=`echo "$template_"|sed 's/XX*$//'`
+
+  # Calculate how many X's we've just removed.
+  template_length_=`echo "$template_" | wc -c`
+  nx_=`echo "$base_template_" | wc -c`
+  nx_=`expr $template_length_ - $nx_`
+
+  err_=
+  i_=1
+  while :; do
+    X_=`rand_bytes_ $nx_`
+    candidate_dir_="$destdir_slash_$base_template_$X_"
+    err_=`mkdir -m 0700 "$candidate_dir_" 2>&1` \
+      && { echo "$candidate_dir_"; return; }
+    test $MAX_TRIES_ -le $i_ && break;
+    i_=`expr $i_ + 1`
+  done
+  fail_ "$err_"
+}
+
+# =============================================================================
+# Core test framework
+
+# An arbitrary prefix to help distinguish test directories.
+testdir_prefix_ () { printf gt; }
+
+# Set up the environment for the test to run in.
+setup_ ()
+{
+  if test "$VERBOSE" = yes; then
+    # Test whether set -x may cause the selected shell to corrupt an
+    # application's stderr.  Many do, including zsh-4.3.10 and the /bin/sh
+    # from SunOS 5.11, OpenBSD 4.7 and Irix 6.5.
+    # If enabling verbose output this way would cause trouble, simply
+    # issue a warning and refrain.
+    if $gl_set_x_corrupts_stderr_; then
+      warn_ "using SHELL=$SHELL with 'set -x' corrupts stderr"
+    else
+      set -x
+    fi
+  fi
+
+  initial_cwd_=$PWD
+
+  # Create and enter the temporary directory.
+  pfx_=`testdir_prefix_`
+  test_dir_=`mktempd_ "$initial_cwd_" "$pfx_-$ME_.XXXX"` \
+    || fail_ "failed to create temporary directory in $initial_cwd_"
+  cd "$test_dir_" || fail_ "failed to cd to temporary directory"
+  # Set variables srcdir, builddir, for the convenience of the test.
+  case $srcdir in
+    /* | ?:*) ;;
+    *) srcdir="../$srcdir" ;;
+  esac
+  builddir=".."
+  export srcdir builddir
+
+  # As autoconf-generated configure scripts do, ensure that IFS
+  # is defined initially, so that saving and restoring $IFS works.
+  gl_init_sh_nl_='
+'
+  IFS=" ""	$gl_init_sh_nl_"
+
+  # This trap statement, along with a trap on 0 below, ensure that the
+  # temporary directory, $test_dir_, is removed upon exit as well as
+  # upon receipt of any of the listed signals.
+  for sig_ in 1 2 3 13 15; do
+    eval "trap 'Exit $(expr $sig_ + 128)' $sig_"
+  done
+
+  # Remove relative and non-accessible directories from PATH, including '.'
+  # and Zero-length entries.
+  saved_IFS="$IFS"
+  IFS=:
+  new_PATH=
+  sep_=
+  for dir in $PATH; do
+    case "$dir" in
+      /*) test -d "$dir/." || continue
+          new_PATH="${new_PATH}${sep_}${dir}"
+          sep_=':';;
+    esac
+  done
+  IFS="$saved_IFS"
+  PATH="$new_PATH"
+  export PATH
+}
+
+# This is a stub function that is run upon trap (upon regular exit and
+# interrupt).  Override it with a per-test function, e.g., to unmount
+# a partition, or to undo any other global state changes.
+cleanup_ () { :; }
+
+# Run the user-overridable cleanup_ function, remove the temporary
+# directory and exit with the incoming value of $?.
+remove_tmp_ ()
+{
+  __st=$?
+  cleanup_
+  if test "$KEEP" = yes; then
+    echo "Not removing temporary directory $test_dir_"
+  else
+    # cd out of the directory we're about to remove
+    cd "$initial_cwd_" || cd / || cd /tmp
+    chmod -R u+rwx "$test_dir_"
+    # If removal fails and exit status was to be 0, then change it to 1.
+    rm -rf "$test_dir_" || { test $__st = 0 && __st=1; }
+  fi
+  exit $__st
+}
+
+# =============================================================================
+# Prepending directories to PATH
+
+# Given a directory name, DIR, if every entry in it that matches *.exe
+# contains only the specified bytes (see the case stmt below), then print
+# a space-separated list of those names and return 0.  Otherwise, don't
+# print anything and return 1.  Naming constraints apply also to DIR.
+find_exe_basenames_ ()
+{
+  feb_dir_=$1
+  feb_fail_=0
+  feb_result_=
+  feb_sp_=
+  for feb_file_ in $feb_dir_/*.exe; do
+    # If there was no *.exe file, or there existed a file named "*.exe" that
+    # was deleted between the above glob expansion and the existence test
+    # below, just skip it.
+    test "x$feb_file_" = "x$feb_dir_/*.exe" && test ! -f "$feb_file_" \
+      && continue
+    # Exempt [.exe, since we can't create a function by that name, yet
+    # we can't invoke [ by PATH search anyways due to shell builtins.
+    test "x$feb_file_" = "x$feb_dir_/[.exe" && continue
+    case $feb_file_ in
+      *[!-a-zA-Z/0-9_.+]*) feb_fail_=1; break;;
+      *) # Remove leading file name components as well as the .exe suffix.
+         feb_file_=${feb_file_##*/}
+         feb_file_=${feb_file_%.exe}
+         feb_result_="$feb_result_$feb_sp_$feb_file_";;
+    esac
+    feb_sp_=' '
+  done
+  test $feb_fail_ = 0 && printf %s "$feb_result_"
+  return $feb_fail_
+}
+
+# Consider the files in directory, $1.
+# For each file name of the form PROG.exe, create an alias named
+# PROG that simply invokes PROG.exe, then return 0.  If any selected
+# file name or the directory name, $1, contains an unexpected character,
+# define no alias and return 1.
+create_exe_shims_ ()
+{
+  case $EXEEXT in
+    '') return 0 ;;
+    .exe) ;;
+    *) echo "$0: unexpected \$EXEEXT value: $EXEEXT" 1>&2; return 1 ;;
+  esac
+
+  base_names_=`find_exe_basenames_ $1` \
+    || { echo "$0 (exe_shim): skipping directory: $1" 1>&2; return 0; }
+
+  if test -n "$base_names_"; then
+    for base_ in $base_names_; do
+      alias "$base_"="$base_$EXEEXT"
+    done
+  fi
+
+  return 0
+}
+
+# Use this function to prepend to PATH an absolute name for each
+# specified, possibly-$initial_cwd_-relative, directory.
+path_prepend_ ()
+{
+  while test $# != 0; do
+    path_dir_=$1
+    case $path_dir_ in
+      '') fail_ "invalid path dir: '$1'";;
+      /* | ?:*) abs_path_dir_=$path_dir_;;
+      *) abs_path_dir_=$initial_cwd_/$path_dir_;;
+    esac
+    case $abs_path_dir_ in
+      *$PATH_SEPARATOR*) fail_ "invalid path dir: '$abs_path_dir_'";;
+    esac
+    PATH="$abs_path_dir_$PATH_SEPARATOR$PATH"
+
+    # Create an alias, FOO, for each FOO.exe in this directory.
+    create_exe_shims_ "$abs_path_dir_" \
+      || fail_ "something failed (above): $abs_path_dir_"
+    shift
+  done
+  export PATH
+}
+
+# =============================================================================
+# Convenience environment variables for the tests
+
+# -----------------------------------------------------------------------------
+
+# Enable glibc's malloc-perturbing option.
+# This is useful for exposing code that depends on the fact that
+# malloc-related functions often return memory that is mostly zeroed.
+# If you have the time and cycles, use valgrind to do an even better job.
+: ${MALLOC_PERTURB_=87}
+export MALLOC_PERTURB_
+
+# -----------------------------------------------------------------------------
+
+# The interpreter for Bourne-shell scripts.
+# No special standards compatibility requirements.
+# Some environments, such as Android, don't have /bin/sh.
+if test -f /bin/sh$EXEEXT; then
+  BOURNE_SHELL=/bin/sh
+else
+  BOURNE_SHELL=sh
+fi
+
+# =============================================================================
+# Convenience functions for the tests
+
+# -----------------------------------------------------------------------------
+# Return value checking
+
+# This is used to simplify checking of the return value
+# which is useful when ensuring a command fails as desired.
+# I.e., just doing `command ... &&fail=1` will not catch
+# a segfault in command for example.  With this helper you
+# instead check an explicit exit code like
+#   returns_ 1 command ... || fail
+returns_ () {
+  # Disable tracing so it doesn't interfere with stderr of the wrapped command
+  { set +x; } 2>/dev/null
+
+  local exp_exit="$1"
+  shift
+  "$@"
+  test $? -eq $exp_exit && ret_=0 || ret_=1
+
+  if test "$VERBOSE" = yes && test "$gl_set_x_corrupts_stderr_" = false; then
+    set -x
+  fi
+  { return $ret_; } 2>/dev/null
+}
+
+# -----------------------------------------------------------------------------
+# Text file comparison
+
+# Emit a header similar to that from diff -u;  Print the simulated "diff"
+# command so that the order of arguments is clear.  Don't bother with @@ lines.
+emit_diff_u_header_ ()
+{
+  printf '%s\n' "diff -u $*" \
+    "--- $1	1970-01-01" \
+    "+++ $2	1970-01-01"
+}
+
+# Arrange not to let diff or cmp operate on /dev/null,
+# since on some systems (at least OSF/1 5.1), that doesn't work.
+# When there are not two arguments, or no argument is /dev/null, return 2.
+# When one argument is /dev/null and the other is not empty,
+# cat the nonempty file to stderr and return 1.
+# Otherwise, return 0.
+compare_dev_null_ ()
+{
+  test $# = 2 || return 2
+
+  if test "x$1" = x/dev/null; then
+    test -s "$2" || return 0
+    emit_diff_u_header_ "$@"; sed 's/^/+/' "$2"
+    return 1
+  fi
+
+  if test "x$2" = x/dev/null; then
+    test -s "$1" || return 0
+    emit_diff_u_header_ "$@"; sed 's/^/-/' "$1"
+    return 1
+  fi
+
+  return 2
+}
+
+for diff_opt_ in -u -U3 -c '' no; do
+  test "$diff_opt_" != no &&
+    diff_out_=`exec 2>/dev/null; diff $diff_opt_ "$0" "$0" < /dev/null` &&
+    break
+done
+if test "$diff_opt_" != no; then
+  if test -z "$diff_out_"; then
+    compare_ () { diff $diff_opt_ "$@"; }
+  else
+    compare_ ()
+    {
+      # If no differences were found, AIX and HP-UX 'diff' produce output
+      # like "No differences encountered".  Hide this output.
+      diff $diff_opt_ "$@" > diff.out
+      diff_status_=$?
+      test $diff_status_ -eq 0 || cat diff.out || diff_status_=2
+      rm -f diff.out || diff_status_=2
+      return $diff_status_
+    }
+  fi
+elif cmp -s /dev/null /dev/null 2>/dev/null; then
+  compare_ () { cmp -s "$@"; }
+else
+  compare_ () { cmp "$@"; }
+fi
+
+# Usage: compare EXPECTED ACTUAL
+#
+# Given compare_dev_null_'s preprocessing, defer to compare_ if 2 or more.
+# Otherwise, propagate $? to caller: any diffs have already been printed.
+compare ()
+{
+  # This looks like it can be factored to use a simple "case $?"
+  # after unchecked compare_dev_null_ invocation, but that would
+  # fail in a "set -e" environment.
+  if compare_dev_null_ "$@"; then
+    return 0
+  else
+    case $? in
+      1) return 1;;
+      *) compare_ "$@";;
+    esac
+  fi
+}
+
+# -----------------------------------------------------------------------------
+
+# If you want to override the testdir_prefix_ function,
+# or to add more utility functions, use this file.
+test -f "$srcdir/init.cfg" \
+  && . "$srcdir/init.cfg"
+
+# =============================================================================
+# Set up the environment for the test to run in.
+
+setup_ "$@"
+# This trap is here, rather than in the setup_ function, because some
+# shells run the exit trap at shell function exit, rather than script exit.
+trap remove_tmp_ 0