tests/cp/link-deref.sh

   1 #!/bin/sh
   2 # Exercise cp --link's behavior regarding the dereferencing of symbolic links.
   3
   4 # Copyright (C) 2013-2024 Free Software Foundation, Inc.
   5
   6 # This program is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 3 of the License, or
   9 # (at your option) any later version.
  10
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  18
  19 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  20 print_ver_ cp
  21
  22 if { grep '^#define HAVE_LINKAT 1' "$CONFIG_HEADER" > /dev/null \
  23      && grep '#undef LINKAT_SYMLINK_NOTSUP' "$CONFIG_HEADER" > /dev/null; } \
  24    || grep '^#define LINK_FOLLOWS_SYMLINKS 0' "$CONFIG_HEADER" > /dev/null; then
  25   # With this config cp will attempt to linkat() to hardlink a symlink.
  26   # So now double check the current file system supports this operation.
  27   ln -s testtarget test_sl || framework_failure_
  28   ln -P test_sl test_hl_sl || framework_failure_
  29   ino_sl="$(stat -c '%i' test_sl)" || framework_failure_
  30   ino_hl="$(stat -c '%i' test_hl_sl)" || framework_failure_
  31   test "$ino_sl" = "$ino_hl" && can_hardlink_to_symlink=1
  32 fi
  33
  34 mkdir dir              || framework_failure_
  35 > file                 || framework_failure_
  36 ln -s dir     dirlink  || framework_failure_
  37 ln -s file    filelink || framework_failure_
  38 ln -s nowhere danglink || framework_failure_
  39
  40 # printf format of the output line.
  41 outformat='%s|result=%s|inode=%s|type=%s|error=%s\n'
  42
  43 for src in dirlink filelink danglink; do
  44   # Get symlink's target.
  45   tgt=$(readlink $src) || framework_failure_
  46   # Get inodes and file type of the symlink (src) and its target (tgt).
  47   # Note: this will fail for 'danglink'; catch it.
  48   ino_src="$(stat -c '%i' $src)" || framework_failure_
  49   typ_src="$(stat -c '%F' $src)" || framework_failure_
  50   ino_tgt="$(stat -c '%i' $tgt 2>/dev/null)" || ino_tgt=
  51   typ_tgt="$(stat -c '%F' $tgt 2>/dev/null)" || typ_tgt=
  52
  53   for o in '' -L -H -P; do
  54
  55     # Skip the -P case where we don't or can't hardlink symlinks
  56     ! test "$can_hardlink_to_symlink" && test "$o" = '-P' && continue
  57
  58     for r in '' -R; do
  59
  60       command="cp --link $o $r $src dst"
  61       $command 2> err
  62       result=$?
  63
  64       # Get inode and file type of the destination (which may fail, too).
  65       ino_dst="$(stat -c '%i' dst 2>/dev/null)" || ini_dst=
  66       typ_dst="$(stat -c '%F' dst 2>/dev/null)" || typ_dst=
  67
  68       # Print the actual result in a certain format.
  69       printf "$outformat" \
  70         "$command"   \
  71         "$result"   \
  72         "$ino_dst"  \
  73         "$typ_dst"  \
  74         "$(cat err)"  \
  75         > out
  76
  77       # What was expected?
  78       if [ "$o" = "-P" ]; then
  79         # cp --link should not dereference if -P is given.
  80         exp_result=0
  81         exp_inode=$ino_src
  82         exp_ftype=$typ_src
  83         exp_error=
  84       elif [ "$src" = 'danglink' ]; then
  85         # Dereferencing should fail for the 'danglink'.
  86         exp_result=1
  87         exp_inode=
  88         exp_ftype=
  89         exp_error="cp: cannot stat 'danglink': No such file or directory"
  90       elif [ "$src" = 'dirlink' ] && [ "$r" != '-R' ]; then
  91         # Dereferencing should fail for the 'dirlink' without -R.
  92         exp_result=1
  93         exp_inode=
  94         exp_ftype=
  95         exp_error="cp: -r not specified; omitting directory 'dirlink'"
  96       elif [ "$src" = 'dirlink' ]; then
  97         # cp --link -R 'dirlink' should create a new directory.
  98         exp_result=0
  99         exp_inode=$ino_dst
 100         exp_ftype=$typ_dst
 101         exp_error=
 102       else
 103         # cp --link 'filelink' should create a hard link to the target.
 104         exp_result=0
 105         exp_inode=$ino_tgt
 106         exp_ftype=$typ_tgt
 107         exp_error=
 108       fi
 109
 110       # Print the expected result in a certain format.
 111       printf "$outformat" \
 112         "$command"   \
 113         "$exp_result" \
 114         "$exp_inode"  \
 115         "$exp_ftype"  \
 116         "$exp_error"  \
 117         > exp
 118
 119       compare exp out || { ls -lid $src $tgt dst; fail=1; }
 120
 121       rm -rf dst err exp out || framework_failure_
 122     done
 123   done
 124 done
 125
 126 Exit $fail