error: undefined reference to time_diff possibly due to missing dependencies

[askb]

We get the following error while building mtcbench, with default version of openvswitch-switch openvswitch-vtep and mininet (mininet is already the newest version (2.2.1-2).) that comes with ubuntu 16.04.

libtool: link: gcc -g -O2 -Wall -I/home/ubuntu/mtcbench/oflops/../openflow//include -Wshadow -Wl,-E -o oflops channel_info.o context.o control.o module_run.o module_default.o oflops.o oflops_pcap.o timer_event.o msg.o log.o traffic_generator.o usage.o  -L/home/ubuntu/mtcbench/oflops/../openflow//lib -ldl -lpcap /home/ubuntu/mtcbench/oflops/.libs/liboflops_test.a -lconfig -lpthread -lnetsnmp
traffic_generator.o: In function `get_next_pkt':
/home/ubuntu/mtcbench/oflops/traffic_generator.c:140: undefined reference to `time_diff'
collect2: error: ld returned 1 exit status
Makefile:577: recipe for target 'oflops' failed
make[2]: *** [oflops] Error 1
make[2]: Leaving directory '/home/ubuntu/mtcbench/oflops'
Makefile:642: recipe for target 'all-recursive' failed
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory '/home/ubuntu/mtcbench/oflops'
Makefile:434: recipe for target 'all' failed
make: *** [all] Error 2

I think the error undefined reference to time_diff'is due to missing dependencies fromoflopswhich gets installed through running the scriptmininet/util/install.sh -b` only available on the master branch mininet.

# Install cbench
function cbench {
    echo "Installing cbench..."

    if [ "$DIST" = "Fedora" -o "$DIST" = "RedHatEnterpriseServer" ]; then
        $install net-snmp-devel libpcap-devel libconfig-devel
        elif [ "$DIST" = "SUSE LINUX"  ]; then
                $install net-snmp-devel libpcap-devel libconfig-devel
    else
        $install libsnmp-dev libpcap-dev libconfig-dev
    fi
    cd $BUILD_DIR/
    # was:  git clone git://gitosis.stanford.edu/oflops.git
    # Use our own fork on github for now:
    git clone git://github.com/mininet/oflops
    cd oflops
    sh boot.sh || true # possible error in autoreconf, so run twice
    sh boot.sh
    ./configure --with-openflow-src-dir=$BUILD_DIR/openflow
    make
    sudo make install || true # make install fails; force past this

Is there a fix or workaround for this issue, allowing using the default version of mininet ?

[panageo]

Hello @askb

We managed to reproduce the issue using Ubuntu 16.04.

Currently the supported distribution is ubuntu 14.04. But there is a workaround for this issue. Following directions of this link

dfarrell07/wcbench#77 (comment)

do the following steps

1. git clone https://github.com/intracom-telecom-sdn/mtcbench.git
2. cd mtcbench folder
3. run provision script to install all mtcbench dependencies: ./deploy/docker/provision.sh
4. run mtcbench build script: ./build_mtcbench.sh
   (step 4 will return you the same error but ignore it. You want to get the binary file under the path oflops/cbench)
5. cd into folder oflops/cbench: cd oflops/cbench/
6. run make and you will get cbench binary

[ljy6j13]

In util.h and util.c, the time_diff function is defined as inline function,I delete the inline keyword and it works.