init.cfg - master - niceSOFT/coreutils

init.cfg
875 строк24 KB
Pádraig Brady
maint: refactor stat syscall determination
24 июл 2026, 15:19
24 июл 2026, 15:198f7ed6c
# This file is sourced by init.sh, *before* its initialization.

# Copyright (C) 2010-2026 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/>.

# This goes hand in hand with the "exec 9>&2;" in tests/Makefile.am's
# TESTS_ENVIRONMENT definition.
stderr_fileno_=9

# Having an unsearchable directory in PATH causes execve to fail with EACCES
# when applied to an unresolvable program name, contrary to the desired ENOENT.
# Avoid the problem by rewriting PATH to exclude unsearchable directories.
# Also, if PATH lacks /sbin and/or /usr/sbin, append it/them.
sanitize_path_()
{
  # FIXME: remove double quotes around $IFS when all tests use init.sh.
  # They constitute a work-around for a bug in FreeBSD 8.1's /bin/sh.
  local saved_IFS="$IFS"
    IFS=:
    set -- $PATH
  IFS=$saved_IFS

  local d d1
  local colon=
  local new_path=
  for d in "$@"; do
    test -z "$d" && d1=. || d1=$d
    if ls -d "$d1/." > /dev/null 2>&1; then
      new_path="$new_path$colon$d"
      colon=':'
    fi
  done

  for d in /sbin /usr/sbin ; do
    case ":$new_path:" in
      *:$d:*) ;;
      *) new_path="$new_path:$d" ;;
    esac
  done

  PATH=$new_path
  export PATH
}

getlimits_()
{
  eval $(getlimits)
  test "$INT_MAX" || fatal_ "running getlimits"
}

require_no_default_acl_()
{
  if getfacl --version < /dev/null > /dev/null 2>&1; then
    getfacl "$1" | grep '^default:' && skip_ 'Default ACL detected'
  else
    ls -ld "$1" | grep '.........+' && skip_ 'ACL detected'
  fi
}

require_acl_()
{
  getfacl --version < /dev/null > /dev/null 2>&1 \
    && setfacl --version < /dev/null > /dev/null 2>&1 \
      || skip_ "This test requires getfacl and setfacl."

  id -u bin > /dev/null 2>&1 \
    || skip_ "This test requires a local user named bin."
}

is_local_dir_()
{
  test $# = 1 || framework_failure_
  df --local "$1" >/dev/null 2>&1
}

require_mount_list_()
{
  local mount_list_fail='cannot read table of mounted file systems'
  df --local 2>&1 | grep -F "$mount_list_fail" >/dev/null &&
    skip_ "$mount_list_fail"
}

dump_mount_list_()
{
  cat /proc/self/mountinfo ||
  cat /proc/self/mounts ||
  cat /proc/mounts ||
  cat /etc/mtab
}

require_local_dir_()
{
  require_mount_list_
  is_local_dir_ . ||
    skip_ "This test must be run on a local file system."
}

require_selinux_()
{
  # When in a chroot of an SELinux-enabled system, but with a mock-simulated
  # SELinux-*disabled* system, recognize that SELinux is disabled system wide:
  grep 'selinuxfs$' /proc/filesystems > /dev/null \
    || { mount | grep ' type selinuxfs ' > /dev/null; } \
    || skip_ "this system lacks SELinux support"

  # Independent of whether SELinux is enabled system-wide,
  # the current file system may lack SELinux support.
  # Also the current build may have SELinux support disabled.
  case $(ls -Zd .) in
    '? .'|'unlabeled .')
      test -z "$CONFIG_HEADER" \
        && framework_failure_ 'CONFIG_HEADER not defined'
      grep '^#define HAVE_SELINUX_SELINUX_H 1' "$CONFIG_HEADER" > /dev/null \
        && selinux_missing_="(file) system" || selinux_missing_="build"
      skip_ "this $selinux_missing_ lacks SELinux support"
    ;;
  esac
}

# Return the SELinux type component if available
get_selinux_type() { ls -Zd "$1" | sed -n 's/.*:\(.*_t\)[: ].*/\1/p'; }

# Whether SELinux Multi Level Security is enabled
mls_enabled_() {
  sestatus 2>&1 |
  grep 'Policy MLS status:.*enabled' > /dev/null
}

# Skip this test if we're not in SELinux "enforcing" mode.
require_selinux_enforcing_()
{
  require_selinux_
  test "$(getenforce)" = Enforcing \
    || skip_ "This test is useful only with SELinux in Enforcing mode."
}

require_smack_()
{
  grep 'smackfs$' /proc/filesystems > /dev/null \
    || skip_ "this system lacks SMACK support"

  test "$(ls -Zd .)" != '? .' \
    || skip_ "this file system lacks SMACK support"
}

require_openat_support_()
{
  # Skip this test if your system has neither the openat-style functions
  # nor /proc/self/fd support with which to emulate them.

  test -z "$CONFIG_HEADER" \
    && framework_failure_ 'CONFIG_HEADER not defined'

  _skip=yes
  grep '^#define HAVE_OPENAT' "$CONFIG_HEADER" > /dev/null && _skip=no
  test -d /proc/self/fd && _skip=no
  if test $_skip = yes; then
    skip_ 'this system lacks openat support'
  fi
}

# Return true if command runs with the
# ulimit specified in the first argument
ulimit_supported_()
{
  local v
  v="$1"
  shift

  local ulimit_start_=$(date +%s) || skip_ 'ulimit: date error'

  (
    # Try to disable core dumps which may
    # occur with memory constraints
    trap '' SEGV; ulimit -c 0;

    ulimit -v $v && "$@"
  ) >/dev/null 2>&1

  ret=$?

  local ulimit_end_=$(date +%s) || skip_ 'ulimit: date error'

  # This can happen on Solaris 11 at least where fork() can give EAGAIN
  # and bash will retry for at least 16 seconds
  test $(($ulimit_end_ - $ulimit_start_)) -ge 10 && skip_ 'ulimit too slow'

  return $ret
}

# Determine the minimum required VM limit to run the given command.
# Output that value to stdout ... to be used by the caller.
# Return 0 in case of success, and a non-Zero value otherwise.
get_min_ulimit_v_()
{
  local v
  local page_size

  # Increase result by this amount to avoid alignment issues
  page_size=$(getconf PAGESIZE || echo 4096)
  page_size=$(($page_size / 1024))

  for v in $( seq 5000 5000 50000 ); do
    ulimit_supported_ $v "$@"; ret=$?
    test $ret = 77 && break;
    if test $ret = 0; then
      local prev_v
      prev_v=$v
      for v in $( seq $(($prev_v-1000)) -1000 1000 ); do
        ulimit_supported_ $v "$@"; ret=$?
        test $ret = 77 && break 2;
        test $ret = 0 ||
          {
            ret_v=$((prev_v + $page_size))
            echo $ret_v
            return 0
          }
        prev_v=$v
      done
    fi
  done
  # The above did not find a working limit.  Echo a very small number - just
  # in case the caller does not handle the non-Zero return value.
  echo 1; return 1
}

require_readable_root_()
{
  test -r / || skip_ "/ is not readable"
}

# Skip the current test if strace is not available or doesn't work
# with the named syscall.  Usage: require_strace_ unlink
require_strace_()
{
  test $# = 1 || framework_failure_

  uses_strace_

  strace -V < /dev/null > /dev/null 2>&1 ||
    skip_ 'no strace program'

  strace -qe "$1" echo > /dev/null 2>&1 ||
    skip_ 'strace -qe "'"$1"'" does not work'

  # On some linux/sparc64 systems, strace works fine on 32-bit executables,
  # but prints only one line of output for every 64-bit executable.
  strace -o log-help ls --help >/dev/null || framework_failure_
  n_lines_help=$(wc -l < log-help)
  rm -f log-help
  if test $n_lines_help = 0 || test $n_lines_help = 1; then
    skip_ 'strace produces no more than one line of output'
  fi
}

# Output a comma-separated list of file-name stat syscalls recognized
# by strace.  Callers that require strace should invoke require_strace_
# separately.
get_stat_syscalls_()
{
  local stats=stat
  local stat
  for stat in statx lstat stat64 lstat64 newfstatat fstatat64; do
    strace -qe "$stat" true > /dev/null 2>&1 &&
      stats="$stats,$stat"
  done
  printf '%s\n' "$stats"
}

# Skip the current test if valgrind doesn't work,
# which could happen if not installed,
# or hasn't support for the built architecture,
# or hasn't appropriate error suppressions installed etc.
require_valgrind_()
{
  valgrind --error-exitcode=1 true 2>/dev/null ||
    skip_ "requires a working valgrind"
}

# Skip the current test if setfacl doesn't work on the current file system,
# which could happen if not installed, or if ACLs are not supported by the
# kernel or the file system, or are turned off via mount options.
#
# Work around the following two issues:
#
# 1) setfacl maps ACLs into file permission bits if on "noacl" file systems.
#
# On file systems which do not support ACLs (e.g. ext4 mounted with -o noacl),
# setfacl operates on the regular file permission bits, and only fails if the
# given ACL spec does not fit into there.  Thus, to test if ACLs really work
# on the current file system, pass an ACL spec which can't be mapped that way.
# "Default" ACLs (-d) seem to fulfill this requirement.
#
# 2) setfacl only invokes the underlying system call if the ACL would change.
#
# If the given ACL spec would not change the ACLs on the file, then setfacl
# does not invoke the underlying system call - setxattr().  Therefore, to test
# if setting ACLs really works on the current file system, call setfacl twice
# with conflicting ACL specs.
require_setfacl_()
{
  local d='acltestdir_'
  mkdir $d || framework_failure_
  local f=0

  setfacl -d -m user::r-x $d \
    && setfacl -d -m user::rwx $d \
    || f=1
  rm -rf $d || framework_failure_
  test $f = 0 \
    || skip_ "setfacl does not work on the current file system"
}

# Require a controlling input 'terminal'.
require_controlling_input_terminal_()
{
  have_input_tty=yes
  tty -s || have_input_tty=no
  test -t 0 || have_input_tty=no
  if test "$have_input_tty" = no; then
    skip_ 'requires controlling input terminal
This test must have a controlling input "terminal", so it may not be
run via "batch", "at", or "ssh".  On some systems, it may not even be
run in the background.'
  fi
}

require_built_()
{
  skip_=no
  for i in "$@"; do
    case " $built_programs " in
      *" $i "*) ;;
      *) echo "$i: not built" 1>&2; skip_=yes ;;
    esac
  done

  test $skip_ = yes && skip_ "required program(s) not built"
}

require_file_system_bytes_free_()
{
  local req=$1
  local expr=$(stat -f --printf "$req / %S <= %a" .)
  $AWK "BEGIN{ exit !($expr) }" \
    || skip_ "this test needs at least $req bytes of free space"
}

uid_is_privileged_()
{
  # Make sure id -u succeeds.
  my_uid=$(id -u) \
    || { echo "$0: cannot run 'id -u'" 1>&2; return 1; }

  # Make sure it gives valid output.
  case $my_uid in
    0) ;;
    *[!0-9]*)
      echo "$0: invalid output ('$my_uid') from 'id -u'" 1>&2
      return 1 ;;
    *) return 1 ;;
  esac
}

get_process_status_()
{
  sed -n '/^State:[	 ]*\([[:alpha:]]\).*/s//\1/p' /proc/$1/status
}

# Convert an ls-style permission string, like drwxr----x and -rw-r-x-wx
# to the equivalent chmod --mode (-m) argument, (=,u=rwx,g=r,o=x and
# =,u=rw,g=rx,o=wx).  Ignore ACLs.
rwx_to_mode_()
{
  case $# in
    1) rwx=$1;;
    *) echo "$0: wrong number of arguments" 1>&2
      echo "Usage: $0 ls-style-mode-string" 1>&2
      return;;
  esac

  case $rwx in
    [ld-][rwx-][rwx-][rwxsS-][rwx-][rwx-][rwxsS-][rwx-][rwx-][rwxtT-]) ;;
    [ld-][rwx-][rwx-][rwxsS-][rwx-][rwx-][rwxsS-][rwx-][rwx-][rwxtT-][+.]) ;;
    *) echo "$0: invalid mode string: $rwx" 1>&2; return;;
  esac

  # Perform these conversions:
  # S  s
  # s  xs
  # T  t
  # t  xt
  # The 'T' and 't' ones are only valid for 'other'.
  s='s/S/@/;s/s/x@/;s/@/s/'
  t='s/T/@/;s/t/x@/;s/@/t/'

  u=$(echo $rwx|sed 's/^.\(...\).*/,u=\1/;s/-//g;s/^,u=$//;'$s)
  g=$(echo $rwx|sed 's/^....\(...\).*/,g=\1/;s/-//g;s/^,g=$//;'$s)
  o=$(echo $rwx|sed 's/^.......\(...\).*/,o=\1/;s/-//g;s/^,o=$//;'$s';'$t)
  echo "=$u$g$o"
}

# Set the global variable stty_reversible_ to a space-separated list of the
# reversible settings from stty.c.  stty_reversible_ also starts and ends
# with a space.
stty_reversible_init_()
{
  require_perl_
  # Pad start with one space for the first option to match in query function.
  stty_reversible_=' '$(perl -lne '/^ *{"(.*?)",.*\bREV\b/ and print $1' \
    "$abs_top_srcdir"/src/stty.c | tr '\n' ' ')
  # Ensure that there are at least 62, i.e., so we're alerted if
  # reformatting the source empties the list.
  test 62 -le $(echo "$stty_reversible_"|wc -w)  \
    || framework_failure_ "too few reversible settings"
}

# Test whether $1 is one of stty's reversible options.
stty_reversible_query_()
{
  case $stty_reversible_ in
    '')
      framework_failure_ "stty_reversible_init_() not called?";;
    *" $1 "*)
      return 0;;
    *)
      return 1;;
  esac
}

skip_if_()
{
  case $1 in
    root) skip_ must be run as root ;;
    non-root) skip_ must be run as non-root ;;
    *) ;;  # FIXME?
  esac
}

very_expensive_()
{
  if test "$RUN_VERY_EXPENSIVE_TESTS" != yes; then
    skip_ 'very expensive: disabled by default
This test is very expensive, so it is disabled by default.
To run it anyway, rerun make check with the RUN_VERY_EXPENSIVE_TESTS
environment variable set to yes.  E.g.,

  env RUN_VERY_EXPENSIVE_TESTS=yes make check

or use the shortcut target of the toplevel Makefile,

  make check-very-expensive
'
  fi
}

expensive_()
{
  if test "$RUN_EXPENSIVE_TESTS" != yes; then
    skip_ 'expensive: disabled by default
This test is relatively expensive, so it is disabled by default.
To run it anyway, rerun make check with the RUN_EXPENSIVE_TESTS
environment variable set to yes.  E.g.,

  env RUN_EXPENSIVE_TESTS=yes make check

or use the shortcut target of the toplevel Makefile,

  make check-expensive
'
  fi
}

# Test whether we can run our just-built root owned rm,
# i.e., that $NON_ROOT_USERNAME has access to the build directory.
nonroot_has_perm_()
{
  require_built_ chroot

  local rm_version=$(
    chroot --skip-chdir --user=$NON_ROOT_USERNAME / env PATH="$PATH" \
      rm --version |
    sed -n '1s/.* //p'
  )
  case ":$rm_version:" in
      :$PACKAGE_VERSION:) ;;
      *) return 1;;
  esac
}

require_root_()
{
  uid_is_privileged_ || skip_ "must be run as root"
  NON_ROOT_USERNAME=${NON_ROOT_USERNAME=nobody}
  NON_ROOT_GID=${NON_ROOT_GID=$(id -g $NON_ROOT_USERNAME)}

  # When the current test invokes chroot, call nonroot_has_perm_
  # to check for a common problem.
  grep '^[ ]*chroot' "../$0" \
    && { nonroot_has_perm_ \
           || skip_ "user $NON_ROOT_USERNAME lacks execute permissions"; }
}

skip_if_root_() { uid_is_privileged_ && skip_ "must be run as non-root"; }

# Set 'groups' to a space-separated list of at least two groups
# of which the user is a member.
require_membership_in_two_groups_()
{
  test $# = 0 || framework_failure_

  # Skip overflow gids used in user namespaces
  overflow_gid=$(cat /proc/sys/kernel/overflowgid 2>/dev/null)
  : "${overflow_gid:=1}"

  groups=
  for group_ in 1 \
    ${COREUTILS_GROUPS-$( (id -G || /usr/xpg4/bin/id -G) 2>/dev/null)}
  do
    # Skip group numbers equal to 2**N - 1 for common N,
    # as they are possibly reserved groups like 'nogroup'.
    case $group_ in
      $overflow_gid | 1 | 32767 | 65535 | 2147483647 | 4294967295) ;;
      9223372036854775807 | 18446744073709551615) ;;
      *) test -z "$groups" || groups="$groups "
         groups="$groups$group_";;
    esac
  done
  case "$groups" in
    *' '*) ;;
    *) skip_ 'requires membership in two groups
this test requires that you be a member of more than one group,
but running '\''id -G'\'' either failed or found just one.  If you really
are a member of at least two groups, then rerun this test with
COREUTILS_GROUPS set in your environment to the space-separated list
of group names or numbers.  E.g.,

  env COREUTILS_GROUPS='\''users cdrom'\'' make check

'
     ;;
  esac
}

# Is /proc/$PID/status supported?
require_proc_pid_status_()
{
    sleep 2 &
    local pid=$!
    sleep .5
    grep '^State:[	 ]*[S]' /proc/$pid/status > /dev/null 2>&1 ||
    skip_ "/proc/$pid/status: missing or 'different'"
    kill $pid
}

# Does trap support signal names?
# Old versions of ash did not.
require_trap_signame_()
{
    (trap '' CHLD) || skip_ 'requires trap with signal name support'
}

# Does kill support sending signal to whole group?
# dash 0.5.8 at least does not.
require_kill_group_()
{
    kill -0 -- -1 || skip_ 'requires kill with group signaling support'
}

# Return nonzero if the specified path is on a file system for
# which SEEK_DATA support exists.
seek_data_capable_()
{
  # Check that SEEK_HOLE support is enabled
  # Note APFS was seen to not create sparse files < 16MiB
  if ! truncate -s16M file.sparse_; then
      warn_ "can't create a sparse file: assuming not SEEK_DATA capable"
      return 1
  fi
  if ! cp --debug --reflink=never file.sparse_ file.sparse_.cp \
       | grep SEEK_HOLE; then
      return 1
  fi

  # Check that SEEK_HOLE is supported on the passed file
  { python3 < /dev/null && PYTHON_=python3; } ||
  { python  < /dev/null && PYTHON_=python; }

  if test x"$PYTHON_" = x; then
      warn_ 'seek_data_capable_: python missing: assuming not SEEK_DATA capable'
      return 1
  fi

  # Use timeout if available to skip cases where SEEK_DATA takes a long time.
  # We saw FreeBSD 9.1 take 35s to return from SEEK_DATA for a 1TiB empty file.
  # Note lseek() is uninterruptible on FreeBSD 9.1, but it does eventually
  # return, and the timeout will ensure a failure return from the process.
  timeout 1 true >/dev/null && TIMEOUT_='timeout 10'

  $TIMEOUT_ $PYTHON_ "$abs_srcdir"/tests/seek-data-capable "$@"
}

# Skip the current test if "." lacks d_type support.
require_dirent_d_type_()
{
  python < /dev/null \
    || skip_ python missing: assuming no d_type support

  python "$abs_srcdir"/tests/d_type-check \
    || skip_ requires d_type support
}

# Skip the current test if we lack Perl.
require_perl_()
{
  : ${PERL=perl}
  $PERL -e 'use warnings' > /dev/null 2>&1 \
    || skip_ 'configure did not find a usable version of Perl'
}

# Does the current (working-dir) file system support sparse files?
require_sparse_support_()
{
  test $# = 0 || framework_failure_
  # Test whether we can create a sparse file.
  # For example, on Darwin6.5 with a file system of type hfs, it's not possible.
  # NTFS requires 128K before a hole appears in a sparse file.
  t=sparse.$$
  dd bs=1 seek=128K of=$t < /dev/null 2> /dev/null
  set x $(du -sk $t)
  kb_size=$2
  rm -f $t
  if test $kb_size -ge 128; then
    skip_ 'this file system does not support sparse files'
  fi
}

# Libraries needed when we compile a shared library.
gcc_shared_libs_=

# Compile a shared lib using the GCC options for doing so.
# Pass input and output file as parameters respectively.
# Any other optional parameters are passed to $CC.
gcc_shared_()
{
  local in=$1
  local out=$2
  shift 2 || return 1

  $CC -Wall -shared --std=gnu99 -fPIC -O2 $* "$in" -o "$out" $gcc_shared_libs_
}

# There are a myriad of ways to build shared libs,
# so we only consider running tests requiring shared libs,
# on platforms that support building them as follows.
require_gcc_shared_()
{
  # Try two different values for gcc_shared_libs_.
  gcc_shared_libs_='-ldl'
  if gcc_shared_ '-' 'd.so' -xc < /dev/null 2>&1; then
    :
  else
    gcc_shared_libs_=
    if gcc_shared_ '-' 'd.so' -xc < /dev/null 2>&1; then
      :
    else
      skip_ '$CC -shared ... failed to build a shared lib'
    fi
  fi
  rm -f d.so
}

mkfifo_or_skip_()
{
  test $# = 1 || framework_failure_
  if ! mkfifo "$1"; then
    # Make an exception of this case -- usually we interpret framework-creation
    # failure as a test failure.  However, in this case, when running on a SunOS
    # system using a file system NFS mounted from OpenBSD, the above fails like
    # this:
    # mkfifo: cannot make fifo 'fifo-10558': Not owner
    skip_ 'unable to create a fifo'
  fi
}

trap_sigpipe_or_skip_()
{
  timeout 1 true >/dev/null ||
    skip_ 'trapping SIGPIPE cannot be safely checked'

  (trap '' PIPE && timeout 10 yes |:) 2>&1 | grep 'Broken pipe' >/dev/null ||
    skip_ 'trapping SIGPIPE is not supported'
}

require_bash_as_SHELL_()
{
  if bash --version >/dev/null 2>&1; then
    SHELL='bash'
  else
    skip_ 'bash is required'
  fi
}

# Disable the current test if the working directory seems to have
# the setgid bit set.
skip_if_setgid_()
{
  setgid_tmpdir=setgid-$$
  (umask 77; mkdir $setgid_tmpdir)
  perms=$(stat --printf %A $setgid_tmpdir)
  rmdir $setgid_tmpdir
  case $perms in
    drwx------);;
    drwxr-xr-x);;  # Windows98 + DJGPP 2.03
    *) skip_ 'this directory has the setgid bit set';;
  esac
}

# Skip if files are created with a different group to the current user
# This can happen due to a setgid dir, or by some other mechanism on OS X:
# https://unix.stackexchange.com/q/63865
# https://bugs.gnu.org/14024#41
skip_if_nondefault_group_()
{
  touch grp.$$
  gen_ug=$(stat -c '%u:%g' grp.$$)
  rm grp.$$
  test "$gen_ug" = "$(id -ru):$(id -rg)" ||
    skip_ 'Files are created with a different gid'
}

skip_if_mcstransd_is_running_()
{
  test $# = 0 || framework_failure_

  # When mcstransd is running, you'll see only the 3-component
  # version of file-system context strings.  Detect that,
  # and if it's running, skip this test.
  __ctx=$(stat --printf='%C\n' .) || framework_failure_
  case $__ctx in
    *:*:*:*) __ctx_ok=1 ;; # four components is ok
    *:*:*)  # three components is ok too if there is no MLS
        mls_enabled_ || __ctx_ok=1 ;;
  esac

  test "$__ctx_ok" ||
   skip_ "unexpected context '$__ctx'; turn off mcstransd"
}

# Skip the current test if umask doesn't work as usual.
# This test should be run in the temporary directory that ends
# up being removed via the trap commands.
working_umask_or_skip_()
{
  umask 022
  touch file1 file2
  chmod 644 file2
  perms=$(ls -l file1 file2 | sed 's/ .*//' | uniq)
  rm -f file1 file2

  case $perms in
  *'
  '*) skip_ 'your build directory has unusual umask semantics'
  esac
}

# Retry a function requiring a sufficient delay to _pass_
# using a truncated exponential backoff method.
#     Example: retry_delay_ dd_reblock_1 .1 6
# This example will call the dd_reblock_1 function with
# an initial delay of .1 second and call it at most 6 times
# with a max delay of 3.2s (doubled each time), or a total of 6.3s
# Further function arguments will be forwarded to the test function.
retry_delay_()
{
  local test_func=$1
  local init_delay=$2
  local max_n_tries=$3
  shift 3 || return 1

  local attempt=1
  local num_sleeps=$attempt
  local time_fail
  while test $attempt -le $max_n_tries; do
    local delay=$($AWK -v n=$num_sleeps -v s="$init_delay" \
                  'BEGIN { print s * n }')
    "$test_func" "$delay" "$@" && { time_fail=0; break; } || time_fail=1
    attempt=$(expr $attempt + 1)
    num_sleeps=$(expr $num_sleeps '*' 2)
  done
  test "$time_fail" = 0
}

detect_tail_mode_()
{
  touch tail.debug || framework_failure_
  returns_ 124 timeout "$1" tail -n0 -F --debug tail.debug 2>tail.mode ||
    framework_failure_
  grep 'using .* mode' tail.mode >/dev/null
}

require_inotify_supported_()
{
  require_built_ tail timeout

  retry_delay_ detect_tail_mode_ .1 4

  # This may skip because:
  #   inotify is not available in this build
  #   inotify is not supported on this file system
  #   tail didn't print the debug info within 1.5s (unlikely)
  grep 'using notification mode' tail.mode >/dev/null ||
    skip_ 'inotify not detected'
}

# Call this with a list of programs under test immediately after
# sourcing init.sh.
print_ver_()
{
  require_built_ "$@"
  if test "$VERBOSE" = yes; then
    local i
    for i in $*; do
      env $i --version
    done
  fi
}

# Are we running on GNU/Hurd?
require_gnu_()
{
  test "$(uname)" = GNU \
    || skip_ 'not running on GNU/Hurd'
}

# Sequence derived from <https://datatracker.ietf.org/doc/rfc9839>.
bad_unicode ()
{
  require_built_ printf

  # invalid UTF8|unpaired surrogate|C1 control|noncharacter
  env printf '\xFF|\xED\xBA\xAD|\u0089|\xED\xA6\xBF\xED\xBF\xBF\n'
}

# AIX has a 'strace' program unrelated to the one we care about.  Avoid
# executing it since it will run forever until manually killed when given
# three to seven arguments.
uses_strace_ ()
{
  strace true > /dev/null 2>&1
  if test $? -ne 0; then
    strace () { false; }
  fi
}

# Return true if passed program is built with ASAN, or UBSAN etc.
sanitizer_build_()
{
  env $(printf '%sSAN_OPTIONS=help=1 ' A UB L M T) "$1" --version 2>&1 |
  grep '[Ss]anitizer' >/dev/null
}

sanitize_path_