test/ext/test-save-symlink-race

   1 #!/usr/bin/env bash
   2 . wvtest.sh
   3 . wvtest-bup.sh
   4 . dev/lib.sh
   5
   6 set -o pipefail
   7
   8 top="$(WVPASS pwd)" || exit $?
   9 tmpdir="$(WVPASS wvmktempdir)" || exit $?
  10 export BUP_DIR="$tmpdir/bup"
  11
  12 bup() { "$top/bup" "$@"; }
  13
  14 # Inject code to coordinate test
  15
  16 WVPASS rm -rf "$tmpdir/mod"
  17 WVPASS mkdir -p "$tmpdir/mod"
  18 cat > "$tmpdir/mod/pause_after_save_stat.py" << EOF
  19
  20 import os, time
  21 import bup.cmd.save
  22
  23 import sys
  24
  25 def test_save_symlink_race_pause_save(name):
  26     if name == b'$tmpdir/save/link':
  27         with open('$tmpdir/waiting-after-save-stat', 'w') as f:
  28              pass
  29         while os.path.exists('$tmpdir/block-save'):
  30            time.sleep(0.01)
  31
  32 bup.cmd.save.after_nondir_metadata_stat = test_save_symlink_race_pause_save
  33
  34 EOF
  35
  36 instrumented-bup()
  37 {
  38     PYTHONPATH="$tmpdir/mod" bup --import-py-module pause_after_save_stat "$@"
  39 }
  40
  41 WVPASS cd "$tmpdir"
  42 WVPASS bup init
  43 WVPASS mkdir "$tmpdir/save"
  44
  45 WVSTART "symlink metadata vs. content race"
  46 WVPASS ln -sf a "$tmpdir/save/link"
  47 WVPASS bup index "$tmpdir/save"
  48 WVPASS touch "$tmpdir/block-save"
  49
  50 (
  51     set -e
  52     while ! test -e "$tmpdir/waiting-after-save-stat"; do
  53         "$top/dev/python" -c 'import time; time.sleep(0.01)'
  54     done
  55     ln -sf abc "$tmpdir/save/link"
  56     rm "$tmpdir/block-save"
  57 ) &
  58 truncator=$!
  59 trap "kill $truncator" EXIT
  60
  61 WVPASS instrumented-bup save -n test "$tmpdir/save"
  62
  63 meta_tgt=$(WVPASS bup ls -ls "test/latest/$tmpdir/save/link" |
  64                sed 's/.* -> //')
  65 data_tgt=$(git -C "$BUP_DIR" show $(WVPASS bup ls -ls "test/latest/$tmpdir/save/link" |
  66                                         sed 's/ .*//'))
  67 WVPASSEQ abc $meta_tgt
  68 WVPASSEQ abc $data_tgt
  69
  70 WVPASS rm -rf "$tmpdir"