xemu/tests/qemu-iotests/common.qemu
Daniel P. Berrangé aae12d4baa iotests: add support for capturing and matching QMP events
When using the _launch_qemu and _send_qemu_cmd functions from
common.qemu, any QMP events get mixed in with the output from
the commands and responses.

This makes it difficult to write a test case as the ordering
of events in the output is not stable.

This introduces a variable 'capture_events' which can be set
to a list of event names. Any events listed in this variable
will not be printed, instead collected in the $QEMU_EVENTS
environment variable.

A new '_wait_event' function can be invoked to collect events
at a fixed point in time. The function will first pull events
cached in $QEMU_EVENTS variable, and if none are found, will
then read more from QMP.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210204124834.774401-11-berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2021-02-08 11:19:51 +00:00

402 lines
12 KiB
Bash

#!/usr/bin/env bash
#
# This allows for launching of multiple QEMU instances, with independent
# communication possible to each instance.
#
# Each instance can choose, at launch, to use either the QMP or the
# HMP (monitor) interface.
#
# All instances are cleaned up via _cleanup_qemu, including killing the
# running qemu instance.
#
# Copyright (C) 2014 Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
QEMU_COMM_TIMEOUT=10
QEMU_FIFO_IN="${QEMU_TEST_DIR}/qmp-in-$$"
QEMU_FIFO_OUT="${QEMU_TEST_DIR}/qmp-out-$$"
QEMU_HANDLE=0
export _QEMU_HANDLE=0
# If bash version is >= 4.1, these will be overwritten and dynamic
# file descriptor values assigned.
_out_fd=3
_in_fd=4
# Wait for expected QMP response from QEMU. Will time out
# after 10 seconds, which counts as failure.
#
# Override QEMU_COMM_TIMEOUT for a timeout different than the
# default 10 seconds
#
# $1: The handle to use
# $2+ All remaining arguments comprise the string to search for
# in the response.
#
# If $silent is set to anything but an empty string, then
# response is not echoed out.
# If $mismatch_only is set, only non-matching responses will
# be echoed.
#
# If $capture_events is non-empty, then any QMP event names it lists
# will not be echoed out, but instead collected in the $QEMU_EVENTS
# variable. The _wait_event function can later be used to receive
# the cached events.
#
# If $only_capture_events is set to anything but an empty string,
# then an error will be raised if a QMP message is seen which is
# not an event listed in $capture_events.
#
# If $success_or_failure is set, the meaning of the arguments is
# changed as follows:
# $2: A string to search for in the response; if found, this indicates
# success and ${QEMU_STATUS[$1]} is set to 0.
# $3: A string to search for in the response; if found, this indicates
# failure and the test is either aborted (if $qemu_error_no_exit
# is not set) or ${QEMU_STATUS[$1]} is set to -1 (otherwise).
_timed_wait_for()
{
local h=${1}
shift
if [ -z "${success_or_failure}" ]; then
success_match=${*}
failure_match=
else
success_match=${1}
failure_match=${2}
fi
timeout=yes
QEMU_STATUS[$h]=0
while IFS= read -t ${QEMU_COMM_TIMEOUT} resp <&${QEMU_OUT[$h]}
do
if [ -n "$capture_events" ]; then
capture=0
local evname
for evname in $capture_events
do
case ${resp} in
*\"event\":\ \"${evname}\"* ) capture=1 ;;
esac
done
if [ $capture = 1 ];
then
ev=$(echo "${resp}" | tr -d '\r' | tr % .)
QEMU_EVENTS="${QEMU_EVENTS:+${QEMU_EVENTS}%}${ev}"
if [ -n "$only_capture_events" ]; then
return
else
continue
fi
fi
fi
if [ -n "$only_capture_events" ]; then
echo "Only expected $capture_events but got ${resp}"
exit 1
fi
if [ -z "${silent}" ] && [ -z "${mismatch_only}" ]; then
echo "${resp}" | _filter_testdir | _filter_qemu \
| _filter_qemu_io | _filter_qmp | _filter_hmp
fi
if [ -n "${failure_match}" ]; then
grep -q "${failure_match}" < <(echo "${resp}")
if [ $? -eq 0 ]; then
timeout=
break
fi
fi
grep -q "${success_match}" < <(echo "${resp}")
if [ $? -eq 0 ]; then
return
fi
if [ -z "${silent}" ] && [ -n "${mismatch_only}" ]; then
echo "${resp}" | _filter_testdir | _filter_qemu \
| _filter_qemu_io | _filter_qmp | _filter_hmp
fi
done
QEMU_STATUS[$h]=-1
if [ -z "${qemu_error_no_exit}" ]; then
if [ -n "${timeout}" ]; then
echo "Timeout waiting for ${success_match} on handle ${h}"
else
echo "Wrong response matching ${failure_match} on handle ${h}"
fi
exit 1 # Timeout or wrong match mean the test failed
fi
}
# Sends QMP or HMP command to QEMU, and waits for the expected response
#
# $1: QEMU handle to use
# $2: String of the QMP command to send
# ${@: -1} (Last string passed)
# String that the QEMU response should contain. If it is a null
# string, do not wait for a response
#
# Set qemu_cmd_repeat to the number of times to repeat the cmd
# until either timeout, or a response. If it is not set, or <=0,
# then the command is only sent once.
#
# If neither $silent nor $mismatch_only is set, and $cmd begins with '{',
# echo the command before sending it the first time.
#
# If $qemu_error_no_exit is set, then even if the expected response
# is not seen, we will not exit. $QEMU_STATUS[$1] will be set it -1 in
# that case.
#
# If $success_or_failure is set, then the last two strings are the
# strings the response will be scanned for. The first of the two
# indicates success, the latter indicates failure. Failure is handled
# like a timeout.
_send_qemu_cmd()
{
local h=${1}
local count=1
local cmd=
local use_error=${qemu_error_no_exit}
shift
if [ ${qemu_cmd_repeat} -gt 0 ] 2>/dev/null; then
count=${qemu_cmd_repeat}
use_error="no"
fi
cmd=$1
shift
# Display QMP being sent, but not HMP (since HMP already echoes its
# input back to output); decide based on leading '{'
if [ -z "$silent" ] && [ -z "$mismatch_only" ] &&
[ "$cmd" != "${cmd#\{}" ]; then
echo "${cmd}" | _filter_testdir | _filter_imgfmt
fi
while [ ${count} -gt 0 ]
do
echo "${cmd}" >&${QEMU_IN[${h}]}
if [ -n "${1}" ]; then
if [ -z "${success_or_failure}" ]; then
qemu_error_no_exit=${use_error} _timed_wait_for ${h} "${1}"
else
qemu_error_no_exit=${use_error} _timed_wait_for ${h} "${1}" "${2}"
fi
if [ ${QEMU_STATUS[$h]} -eq 0 ]; then
return
fi
fi
let count--;
done
if [ ${QEMU_STATUS[$h]} -ne 0 ] && [ -z "${qemu_error_no_exit}" ]; then
echo "Timeout waiting for command ${1} response on handle ${h}"
exit 1 #Timeout means the test failed
fi
}
# Check event cache for a named QMP event
#
# Input parameters:
# $1: Name of the QMP event to check for
#
# Checks if the named QMP event that was previously captured
# into $QEMU_EVENTS. When matched, the QMP event will be echoed
# and the $matched variable set to 1.
#
# _wait_event is more suitable for test usage in most cases
_check_cached_events()
{
local evname=${1}
local match="\"event\": \"$evname\""
matched=0
if [ -n "$QEMU_EVENTS" ]; then
CURRENT_QEMU_EVENTS=$QEMU_EVENTS
QEMU_EVENTS=
old_IFS=$IFS
IFS="%"
for ev in $CURRENT_QEMU_EVENTS
do
grep -q "$match" < <(echo "${ev}")
if [ $? -eq 0 ] && [ $matched = 0 ]; then
echo "${ev}" | _filter_testdir | _filter_qemu \
| _filter_qemu_io | _filter_qmp | _filter_hmp
matched=1
else
QEMU_EVENTS="${QEMU_EVENTS:+${QEMU_EVENTS}%}${ev}"
fi
done
IFS=$old_IFS
fi
}
# Wait for a named QMP event
#
# Input parameters:
# $1: QEMU handle to use
# $2: Name of the QMP event to wait for
#
# Checks if the named QMP even was previously captured
# into $QEMU_EVENTS. If none are present, then waits for the
# event to arrive on the QMP channel. When matched, the QMP
# event will be echoed
_wait_event()
{
local h=${1}
local evname=${2}
while true
do
_check_cached_events $evname
if [ $matched = 1 ];
then
return
fi
only_capture_events=1 qemu_error_no_exit=1 _timed_wait_for ${h}
if [ ${QEMU_STATUS[$h]} -ne 0 ] ; then
echo "Timeout waiting for event ${evname} on handle ${h}"
exit 1 #Timeout means the test failed
fi
done
}
# Launch a QEMU process.
#
# Input parameters:
# $qemu_comm_method: set this variable to 'monitor' (case insensitive)
# to use the QEMU HMP monitor for communication.
# Otherwise, the default of QMP is used.
# $qmp_pretty: Set this variable to 'y' to enable QMP pretty printing.
# $keep_stderr: Set this variable to 'y' to keep QEMU's stderr output on stderr.
# If this variable is empty, stderr will be redirected to stdout.
# Returns:
# $QEMU_HANDLE: set to a handle value to communicate with this QEMU instance.
#
_launch_qemu()
{
local comm=
local fifo_out=
local fifo_in=
if (shopt -s nocasematch; [[ "${qemu_comm_method}" == "monitor" ]])
then
comm="-monitor stdio"
else
local qemu_comm_method="qmp"
if [ "$qmp_pretty" = "y" ]; then
comm="-monitor none -qmp-pretty stdio"
else
comm="-monitor none -qmp stdio"
fi
fi
fifo_out=${QEMU_FIFO_OUT}_${_QEMU_HANDLE}
fifo_in=${QEMU_FIFO_IN}_${_QEMU_HANDLE}
mkfifo "${fifo_out}"
mkfifo "${fifo_in}"
object_options=
if [ -n "$IMGKEYSECRET" ]; then
object_options="--object secret,id=keysec0,data=$IMGKEYSECRET"
fi
if [ -z "$keep_stderr" ]; then
QEMU_NEED_PID='y'\
${QEMU} ${object_options} -nographic -serial none ${comm} "${@}" >"${fifo_out}" \
2>&1 \
<"${fifo_in}" &
elif [ "$keep_stderr" = "y" ]; then
QEMU_NEED_PID='y'\
${QEMU} ${object_options} -nographic -serial none ${comm} "${@}" >"${fifo_out}" \
<"${fifo_in}" &
else
exit 1
fi
if [[ "${BASH_VERSINFO[0]}" -ge "5" ||
("${BASH_VERSINFO[0]}" -ge "4" && "${BASH_VERSINFO[1]}" -ge "1") ]]
then
# bash >= 4.1 required for automatic fd
exec {_out_fd}<"${fifo_out}"
exec {_in_fd}>"${fifo_in}"
else
let _out_fd++
let _in_fd++
eval "exec ${_out_fd}<'${fifo_out}'"
eval "exec ${_in_fd}>'${fifo_in}'"
fi
QEMU_OUT[${_QEMU_HANDLE}]=${_out_fd}
QEMU_IN[${_QEMU_HANDLE}]=${_in_fd}
QEMU_STATUS[${_QEMU_HANDLE}]=0
if [ "${qemu_comm_method}" == "qmp" ]
then
# Don't print response, since it has version information in it
silent=yes _timed_wait_for ${_QEMU_HANDLE} "capabilities"
if [ "$qmp_pretty" = "y" ]; then
silent=yes _timed_wait_for ${_QEMU_HANDLE} "^}"
fi
fi
QEMU_HANDLE=${_QEMU_HANDLE}
let _QEMU_HANDLE++
}
# Silently kills the QEMU process
#
# If $wait is set to anything other than the empty string, the process will not
# be killed but only waited for, and any output will be forwarded to stdout. If
# $wait is empty, the process will be killed and all output will be suppressed.
_cleanup_qemu()
{
# QEMU_PID[], QEMU_IN[], QEMU_OUT[] all use same indices
for i in "${!QEMU_OUT[@]}"
do
local QEMU_PID
if [ -f "${QEMU_TEST_DIR}/qemu-${i}.pid" ]; then
read QEMU_PID < "${QEMU_TEST_DIR}/qemu-${i}.pid"
rm -f "${QEMU_TEST_DIR}/qemu-${i}.pid"
if [ -z "${wait}" ] && [ -n "${QEMU_PID}" ]; then
kill -KILL ${QEMU_PID} 2>/dev/null
fi
if [ -n "${QEMU_PID}" ]; then
wait ${QEMU_PID} 2>/dev/null # silent kill
fi
fi
if [ -n "${wait}" ]; then
cat <&${QEMU_OUT[$i]} | _filter_testdir | _filter_qemu \
| _filter_qemu_io | _filter_qmp | _filter_hmp
fi
rm -f "${QEMU_FIFO_IN}_${i}" "${QEMU_FIFO_OUT}_${i}"
eval "exec ${QEMU_IN[$i]}<&-" # close file descriptors
eval "exec ${QEMU_OUT[$i]}<&-"
unset QEMU_IN[$i]
unset QEMU_OUT[$i]
done
}