tests/qemu-iotests/common.nbd

   1 #!/usr/bin/env bash
   2 # -*- shell-script-mode -*-
   3 #
   4 # Helpers for NBD server related config
   5 #
   6 # Copyright (C) 2018 Red Hat, Inc.
   7 #
   8 # This program is free software; you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation; either version 2 of the License, or
  11 # (at your option) any later version.
  12 #
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17 #
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 #
  21
  22 nbd_unix_socket="${SOCK_DIR}/qemu-nbd.sock"
  23 nbd_tcp_addr="127.0.0.1"
  24 nbd_pid_file="${TEST_DIR}/qemu-nbd.pid"
  25 nbd_stderr_fifo="${TEST_DIR}/qemu-nbd.fifo"
  26
  27 # If bash version is >= 4.1, this will be overwritten by a dynamically
  28 # assigned file descriptor value.
  29 nbd_fifo_fd=10
  30
  31 nbd_server_stop()
  32 {
  33     local NBD_PID
  34     if [ -f "$nbd_pid_file" ]; then
  35         read NBD_PID < "$nbd_pid_file"
  36         rm -f "$nbd_pid_file"
  37         if [ -n "$NBD_PID" ]; then
  38             kill "$NBD_PID"
  39         fi
  40     fi
  41     rm -f "$nbd_unix_socket" "$nbd_stderr_fifo"
  42 }
  43
  44 nbd_server_start_unix_socket()
  45 {
  46     nbd_server_stop
  47     $QEMU_NBD -v -t -k "$nbd_unix_socket" --fork "$@"
  48 }
  49
  50 nbd_server_start_tcp_socket()
  51 {
  52     nbd_server_stop
  53
  54     mkfifo "$nbd_stderr_fifo"
  55     for ((port = 10809; port <= 10909; port++))
  56     do
  57         # Redirect stderr to FIFO, so we can later decide whether we
  58         # want to read it or to redirect it to our stderr, depending
  59         # on whether the command fails or not
  60         $QEMU_NBD -v -t -b $nbd_tcp_addr -p $port --fork "$@" \
  61             2> "$nbd_stderr_fifo" &
  62
  63         # Taken from common.qemu
  64         if [[ "${BASH_VERSINFO[0]}" -ge "5" ||
  65             ("${BASH_VERSINFO[0]}" -ge "4" && "${BASH_VERSINFO[1]}" -ge "1") ]]
  66         then
  67             exec {nbd_fifo_fd}<"$nbd_stderr_fifo"
  68         else
  69             let _nbd_fifo_fd++
  70             eval "exec ${_nbd_fifo_fd}<'$nbd_stderr_fifo'"
  71         fi
  72         wait $!
  73
  74         if test $? == 0
  75         then
  76             # Success, redirect qemu-nbd's stderr to our stderr
  77             nbd_tcp_port=$port
  78             (cat <&$nbd_fifo_fd >&2) &
  79             eval "exec $nbd_fifo_fd>&-"
  80             return
  81         fi
  82
  83         # Failure, read the output
  84         output=$(cat <&$nbd_fifo_fd)
  85         eval "exec $nbd_fifo_fd>&-"
  86
  87         if ! echo "$output" | grep -q "Address already in use"
  88         then
  89             # Unknown error, print it
  90             echo "$output" >&2
  91             rm -f "$nbd_stderr_fifo"
  92             exit 1
  93         fi
  94     done
  95
  96     echo "Cannot find free TCP port for nbd in range 10809-10909"
  97     rm -f "$nbd_stderr_fifo"
  98     exit 1
  99 }