xref: /qemu/tests/qemu-iotests/common.nbd (revision 27a4a30e)
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
22nbd_unix_socket="${SOCK_DIR}/qemu-nbd.sock"
23nbd_tcp_addr="127.0.0.1"
24nbd_pid_file="${TEST_DIR}/qemu-nbd.pid"
25nbd_stderr_fifo="${TEST_DIR}/qemu-nbd.fifo"
26
27# If bash version is >= 4.1, this will be overwritten by a dynamically
28# assigned file descriptor value.
29nbd_fifo_fd=10
30
31nbd_server_stop()
32{
33    local NBD_PID
34    if [ -f "$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
44nbd_server_start_unix_socket()
45{
46    nbd_server_stop
47    $QEMU_NBD -v -t -k "$nbd_unix_socket" --fork "$@"
48}
49
50nbd_server_start_tcp_socket()
51{
52    nbd_server_stop
53
54    mkfifo "$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}
100