tests/test-truncate4.sh

   1 #!/usr/bin/env bash
   2 # nbdkit
   3 # Copyright Red Hat
   4 #
   5 # Redistribution and use in source and binary forms, with or without
   6 # modification, are permitted provided that the following conditions are
   7 # met:
   8 #
   9 # * Redistributions of source code must retain the above copyright
  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 # Regression test when next->get_size changes between connections.
  34 #
  35 # For now, NBD does not support dynamic resize; but the file plugin
  36 # reads size from the file system for each new connection, at which
  37 # point the client remembers that size for the life of the connection.
  38 #
  39 # We are testing that connection A can still see the tail of a file,
  40 # even when connection B is opened while the file was temporarily
  41 # shorter.  If the actions of connection B affect the size visible
  42 # through connection A, we didn't isolate per-connection state.
  43
  44 source ./functions.sh
  45 set -e
  46 set -x
  47
  48 requires nbdsh --version
  49
  50 sock=$(mktemp -u /tmp/nbdkit-test-sock.XXXXXX)
  51 data=truncate4.data
  52 files="truncate4.pid $sock $data"
  53 rm -f $files
  54 cleanup_fn rm -f $files
  55
  56 # Create and truncate the file.
  57 : > $data
  58
  59 # Run nbdkit with file plugin and truncate filter in front.
  60 start_nbdkit -P truncate4.pid -U $sock \
  61        --filter=truncate \
  62        file $data \
  63        round-up=1024
  64
  65 export data sock
  66 nbdsh -c '
  67 import os
  68
  69 data = os.environ["data"]
  70 sock = os.environ["sock"]
  71
  72 def restore_file():
  73     # Original test data, 1024 bytes of "TEST" repeated.
  74     with open(data, "w") as file:
  75         file.write("TEST"*256)
  76
  77 restore_file()
  78
  79 print("Connection A.", flush=True)
  80 connA = nbd.NBD()
  81 connA.set_handle_name("A")
  82 connA.connect_unix(sock)
  83 print("Check the size.", flush=True)
  84 assert connA.get_size() == 1024
  85
  86 print("Truncate %s to 512 bytes." % data, flush=True)
  87 os.truncate(data, 512)
  88
  89 print("Connection B.", flush=True)
  90 connB = nbd.NBD()
  91 connB.set_handle_name("B")
  92 connB.connect_unix(sock)
  93 print("Check the size.", flush=True)
  94 assert connB.get_size() == 1024 # because of the round-up parameter
  95 print("Read data from connection B.", flush=True)
  96 buf = connB.pread(1024, 0)
  97 assert buf == b"TEST"*128 + b"\0"*512
  98
  99 print("Restore the file size and original data.", flush=True)
 100 restore_file()
 101
 102 print("Read data from connection A.", flush=True)
 103 buf = connA.pread(1024, 0)
 104 assert 1024 == len(buf)
 105 assert buf == b"TEST"*256
 106 '