tests/test-retry-size.sh

   1 #!/usr/bin/env bash
   2 # nbdkit
   3 # Copyright Red Hat
   4 #
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   6 # modification, are permitted provided that the following conditions are
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  10 # notice, this list of conditions and the following disclaimer.
  11 #
  12 # * Redistributions in binary form must reproduce the above copyright
  13 # notice, this list of conditions and the following disclaimer in the
  14 # documentation and/or other materials provided with the distribution.
  15 #
  16 # * Neither the name of Red Hat nor the names of its contributors may be
  17 # used to endorse or promote products derived from this software without
  18 # specific prior written permission.
  19 #
  20 # THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
  21 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  22 # THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  23 # PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
  24 # CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  25 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  26 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  27 # USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  28 # ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  29 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  30 # OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31 # SUCH DAMAGE.
  32
  33 source ./functions.sh
  34 set -e
  35 set -x
  36
  37 fail=0
  38
  39 requires_plugin sh
  40 requires_nbdsh_uri
  41 requires dd iflag=count_bytes </dev/null
  42
  43 files="retry-size-open-count retry-size-fail"
  44 rm -f $files
  45 cleanup_fn rm -f $files
  46
  47 touch retry-size-open-count
  48 start_t=$SECONDS
  49
  50 # Create a custom plugin which will test retrying.
  51 st=0
  52 nbdkit -v -U - \
  53        sh - \
  54        --filter=retry retry-delay=1 \
  55        --run 'nbdsh -u "$uri" \
  56            -c "h.pread(512, 0)" -c "h.cache(512, 512)"' <<'EOF' || st=$?
  57 #!/usr/bin/env bash
  58 case "$1" in
  59     open)
  60         # Count how many times the connection is (re-)opened.
  61         read i < retry-size-open-count
  62         echo $((i+1)) > retry-size-open-count
  63         ;;
  64     get_size)
  65         # Temporarily report a smaller size
  66         read i < retry-size-open-count
  67         if [ $i = 2 ]; then
  68             echo 512
  69         else
  70             echo 1024
  71         fi
  72         ;;
  73     can_cache)
  74         echo native
  75         ;;
  76     pread | cache)
  77         # Fail first open unconditionally
  78         # On second open, ensure nbdkit obeys smaller bound
  79         # On third open, allow read to succeed
  80         read i < retry-size-open-count
  81         case $i in
  82             1) echo "EIO too soon to read" >&2
  83                exit 1 ;;
  84             2) if [ $(( $3 + $4 )) -gt 512 ]; then
  85                    touch retry-size-fail
  86                fi ;;
  87         esac
  88         if [ $1 = pread ]; then
  89             dd if=/dev/zero count=$3 iflag=count_bytes
  90         fi
  91         ;;
  92     *) exit 2 ;;
  93 esac
  94 EOF
  95
  96 # In this test we should see the following:
  97 # open reports size 1024
  98 # first pread FAILS
  99 # retry and wait 1 seconds
 100 # open reports size 512
 101 # first pread succeeds
 102 # second pread FAILS without calling into pread
 103 # retry and wait 1 seconds
 104 # open reports size 1024
 105 # second pread succeeds
 106
 107 # The minimum time for the test should be 1+1 = 2 seconds.
 108 end_t=$SECONDS
 109 if [ $((end_t - start_t)) -lt 2 ]; then
 110     echo "$0: test ran too quickly"
 111     fail=1
 112 fi
 113
 114 # Check the handle was opened 3 times (first open + reopens).
 115 read open_count < retry-size-open-count
 116 if [ $open_count -ne 3 ]; then
 117     echo "$0: open-count ($open_count) != 3"
 118     fail=1
 119 fi
 120
 121 # Check that nbdkit checked bounds
 122 if [ -e retry-size-fail ]; then
 123     echo "$0: nbdkit read past EOF"
 124     fail=1
 125 fi
 126
 127 exit $fail