Re: [Qemu-devel] [PATCH v2 1/5] block: qemu-iotests - add common.qemu, for bash-controlled qemu tests

[Jeff Cody <jcody@redhat.com>]

On Thu, Apr 10, 2014 at 01:27:37PM +0800, Fam Zheng wrote:
> On Wed, 04/09 22:41, Jeff Cody wrote:
> > This creates some common functions for bash language qemu-iotests
> > to control, and communicate with, a running QEMU process.
> > 
> > 4 functions are introduced:
> > 
> >     1. _launch_qemu()
> >         This launches the QEMU process(es), and sets up the file
> >         descriptors and fifos for communication.  You can choose to
> >         launch each QEMU process listening for either QMP or HMP
> >         monitor.  You can call this function multiple times, and
> >         save the handle returned from each.  The returned handle is
> >         in $QEMU_HANDLE.  You must copy this value.
> > 
> > Commands 2 and 3 use the handle received from _launch_qemu(), to talk
> > to the appropriate process.
> > 
> >     2. _send_qemu_cmd()
> >         Sends a command string, specified by $2, to QEMU.  If $2 is
> >         non-NULL, _send_qemu_cmd() will wait to receive $2 as a
> 
> Do you mean $3 in this sentence?
>

Oops, yes - thanks.

> >         required result string from QEMU.  Failure to receive $3 will
> >         cause the test to fail.  The command can optionally be retried
> >         $qemu_cmd_repeat number of times.
> > 
> >     3. _timed_wait_for()
> >         Waits for a response, for up to a default of 10 seconds.  If
> >         $2 is not seen in that time (anywhere in the response), then
> >         the test fails.  Primarily used by _send_qemu_cmd, but could
> >         be useful standalone, as well.  To prevent automatic exit
> >         (and therefore test failure), set $qemu_wait_no_error to a
> >         non-NULL value.  If $silent is a non-NULL value, then output
> >         to stdout will be suppressed.
> > 
> >     4. _cleanup_qemu()
> >         Kills the running QEMU processes, and removes the fifos.
> > 
> > Signed-off-by: Jeff Cody <jcody@redhat.com>
> > ---
> >  tests/qemu-iotests/common.qemu | 195 +++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 195 insertions(+)
> >  create mode 100644 tests/qemu-iotests/common.qemu
> > 
> > diff --git a/tests/qemu-iotests/common.qemu b/tests/qemu-iotests/common.qemu
> > new file mode 100644
> > index 0000000..12c42f1
> > --- /dev/null
> > +++ b/tests/qemu-iotests/common.qemu
> > @@ -0,0 +1,195 @@
> > +#!/bin/bash
> > +#
> > +# This allows for launching of multiple QEMU instances, with independent
> > +# communication possible to each instance.
> > +#
> > +# Each instance can choose, at launch, to use either the QMP or the
> > +# HMP (monitor) interface.
> > +#
> > +# All instances are cleaned up via _cleanup_qemu, including killing the
> > +# running qemu instance.
> > +#
> > +# Copyright (C) 2014 Red Hat, Inc.
> > +#
> > +# This program is free software; you can redistribute it and/or modify
> > +# it under the terms of the GNU General Public License as published by
> > +# the Free Software Foundation; either version 2 of the License, or
> > +# (at your option) any later version.
> > +#
> > +# This program is distributed in the hope that it will be useful,
> > +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> > +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > +# GNU General Public License for more details.
> > +#
> > +# You should have received a copy of the GNU General Public License
> > +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
> > +#
> > +
> > +QEMU_COMM_TIMEOUT=10
> > +
> > +QEMU_FIFO_IN="${TEST_DIR}/qmp-in-$$"
> > +QEMU_FIFO_OUT="${TEST_DIR}/qmp-out-$$"
> > +
> > +QEMU_PID=
> > +_QEMU_HANDLE=0
> > +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 $silent is set to anything but an empty string, then
> > +# response is not echoed out.
> > +function _timed_wait_for()
> > +{
> > +    local h=${1}
> > +    shift
> > +
> > +    QEMU_STATUS[$h]=0
> > +    while read -t ${QEMU_COMM_TIMEOUT} resp <&${QEMU_OUT[$h]}
> > +    do
> > +        if [ -z "${silent}" ]; then
> > +            echo "${resp}" | _filter_testdir | _filter_qemu \
> > +                           | _filter_qemu_io | _filter_qmp
> > +        fi
> > +        grep -q "${*}" < <(echo ${resp})
> > +        if [ $? -eq 0 ]; then
> > +            return
> > +        fi
> > +    done
> > +    QEMU_STATUS[$h]=-1
> > +    if [ -z "${qemu_wait_no_error}" ]; then
> > +        echo "Timeout waiting for ${*} on handle ${h}"
> > +        exit 1  # Timeout means 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
> > +# ${@: -1}  (Last string passed)
> > +#             String that the QEMU response should contain. If it is a null
> > +#             string, do not wait for a response
> > +#
> > +# Set qemu_cmd_repeat to the number of times to repeat the cmd
> > +# until either timeout, or a response.  If it is not set, or <=0,
> > +# then the command is only sent once.
> > +#
> > +function _send_qemu_cmd()
> > +{
> > +    local h=${1}
> > +    local count=1
> > +    local cmd=
> > +    local use_error=
> > +    shift
> > +
> > +    if [ ${qemu_cmd_repeat} -gt 0 ] 2>/dev/null; then
> > +        count=${qemu_cmd_repeat}
> > +        use_error="no"
> > +    fi
> > +    # This array element extraction is done to accomodate pathnames with spaces
> > +    cmd=${@: 1:${#@}-1}
> > +    shift $(($# - 1))
> > +
> > +    while [ ${count} -gt 0 ]
> > +    do
> > +        echo "${cmd}" >&${QEMU_IN[${h}]}
> > +        if [ -n "${1}" ]; then
> > +            qemu_wait_no_error=${use_error} _timed_wait_for ${h} "${1}"
> > +            if [ ${QEMU_STATUS[$h]} -eq 0 ]; then
> > +                return
> > +            fi
> > +        fi
> > +        let count--;
> > +    done
> > +    if [ ${QEMU_STATUS[$h]} -ne 0 ]; then
> > +        echo "Timeout waiting for ${1} on handle ${h}"
> > +        exit 1 #Timeout means the test failed
> > +    fi
> > +}
> > +
> > +
> > +# 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.
> > +# Returns:
> > +# $QEMU_HANDLE: set to a handle value to communicate with this QEMU instance.
> > +#
> > +function _launch_qemu()
> > +{
> > +    local comm=
> > +    local fifo_out=
> > +    local fifo_in=
> > +
> > +    if (shopt -s nocasematch; [[ "${qemu_comm_method}" == "monitor" ]])
> > +    then
> > +        comm="-monitor stdio"
> > +    else
> > +        local qemu_comm_method="qmp"
> > +        comm="-monitor none -qmp stdio"
> > +    fi
> > +
> > +    fifo_out=${QEMU_FIFO_OUT}_${_QEMU_HANDLE}
> > +    fifo_in=${QEMU_FIFO_IN}_${_QEMU_HANDLE}
> > +    mkfifo "${fifo_out}"
> > +    mkfifo "${fifo_in}"
> > +
> > +    "${QEMU}" -nographic -serial none ${comm} "${@}" 2>&1 \
> > +                                                     >"${fifo_out}" \
> > +                                                     <"${fifo_in}" &
> 
> Maybe add "-machine accel=qtest"?
>

OK

> 
> > +    QEMU_PID[${_QEMU_HANDLE}]=$!
> > +
> > +    if [ "${BASH_VERSINFO[0]}" -ge "4" ] && [ "${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 ${_QEMU_HANDLE} "capabilities"
> > +    fi
> > +    QEMU_HANDLE=${_QEMU_HANDLE}
> > +    let _QEMU_HANDLE++
> > +}
> > +
> > +
> > +# Silenty kills the QEMU process
> > +function _cleanup_qemu()
> > +{
> > +    # QEMU_PID[], QEMU_IN[], QEMU_OUT[] all use same indices
> > +    for i in "${!QEMU_OUT[@]}"
> > +    do
> > +        kill -KILL ${QEMU_PID[$i]}
> > +        wait ${QEMU_PID[$i]} 2>/dev/null # silent kill
> > +        rm -f "${QEMU_FIFO_IN}_${i}" "${QEMU_FIFO_OUT}_${i}"
> > +    done
> > +}
> > +
> > -- 
> > 1.8.3.1
> > 
> >