Unable to open GPIO export interface: Permission denied

[hemachowdary]

hi , i have a simple code for operating LED using raspberry pi. when i am running that using tomcat server i am getting following error.

HTTP Status 500 - java.lang.RuntimeException: Unable to open GPIO export interface: Permission denied

type Exception report

message java.lang.RuntimeException: Unable to open GPIO export interface: Permission denied

description The server encountered an internal error (java.lang.RuntimeException: Unable to open GPIO export interface: Permission denied ) that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: java.lang.RuntimeException: Unable to open GPIO export interface: Permission denied

com.vaadin.server.VaadinServlet.handleServiceException(VaadinServlet.java:580)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:343)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:201)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)

root cause

java.lang.RuntimeException: Unable to open GPIO export interface: Permission denied

com.pi4j.wiringpi.GpioUtil.export(Native Method)
com.pi4j.io.gpio.RaspiGpioProvider.export(RaspiGpioProvider.java:67)
com.pi4j.io.gpio.impl.GpioPinImpl.export(GpioPinImpl.java:165)
com.pi4j.io.gpio.impl.GpioControllerImpl.provisionPin(GpioControllerImpl.java:520)
com.pi4j.io.gpio.impl.GpioControllerImpl.provisionDigitalOutputPin(GpioControllerImpl.java:645)
com.pi4j.io.gpio.impl.GpioControllerImpl.provisionDigitalOutputPin(GpioControllerImpl.java:672)
com.pi4j.io.gpio.impl.GpioControllerImpl.provisionDigitalOutputPin(GpioControllerImpl.java:684)
com.example.raspberrypigpioexample01.Raspberrypigpioexample01UI.init(Raspberrypigpioexample01UI.java:19)
com.vaadin.ui.UI.doInit(UI.java:529)
com.vaadin.server.AbstractCommunicationManager.getBrowserDetailsUI(AbstractCommunicationManager.java:2468)
com.vaadin.server.AbstractCommunicationManager.handleBrowserDetailsRequest(AbstractCommunicationManager.java:2362)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:325)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:201)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)

note The full stack trace of the root cause is available in the Apache Tomcat/7.0.28 logs.

can any one please help me to solve this issue ?

Thanks in advance

[radut]

try running the java as root first. If that solved then you must give permision to user tomcat/ pi which one is used for running tomcat to access GPIO

[radut]

http://stackoverflow.com/questions/12133860/accessing-the-gpio-of-a-raspberry-pi-without-sudo http://www.raspberrypi.org/forums/viewtopic.php?f=44&t=8999 https://github.com/quick2wire/quick2wire-gpio-admin

[hemachowdary]

hi radut, Thanks for your quick reply. i have tried them but still i am getting same issue.

[radut]

please write the output of : ps -ef |grep java

[hemachowdary]

output is :

tomcat7 2364 1 98 08:36 ? 00:00:58 /usr/lib/jvm/java-7-openjdk-armhf/bin/java -Djava.util.logging.config.file=/var/lib/tomcat7/conf/logging.properties -Djava.awt.headless=true -Xmx128m -XX:+UseConcMarkSweepGC -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/usr/share/tomcat7/endorsed -classpath /usr/share/tomcat7/bin/bootstrap.jar:/usr/share/tomcat7/bin/tomcat-juli.jar -Dcatalina.base=/var/lib/tomcat7 -Dcatalina.home=/usr/share/tomcat7 -Djava.io.tmpdir=/tmp/tomcat7-tomcat7-tmp org.apache.catalina.startup.Bootstrap start pi 2402 2228 0 08:37 pts/0 00:00:00 grep --color=auto java

[radut]

here is user tomcat7. try with root. do you have init.d script ? please write it here (because there are >10 init.d scripts for tomcat :) )

[hemachowdary]

no i doesnt have init.d script.........

[radut]

how do you start tomcat then ?

[hemachowdary]

i use following command : sudo service tomcat7 start

[radut]

did you checked for any tomcat7 file in /etc/init.d/ ? I belive that service is a wrapper over a init script:-?

[hemachowdary]

yes i am having tomcat7 file in that path ........

[radut]

write it here

[hemachowdary]

!/bin/sh

#

/etc/init.d/tomcat7 -- startup script for the Tomcat 6 servlet engine

#

Written by Miquel van Smoorenburg miquels@cistron.nl.

Modified for Debian GNU/Linux by Ian Murdock imurdock@gnu.ai.mit.edu.

Modified for Tomcat by Stefan Gybas sgybas@debian.org.

Modified for Tomcat6 by Thierry Carrez thierry.carrez@ubuntu.com.

Modified for Tomcat7 by Ernesto Hernandez-Novich emhn@itverx.com.ve.

Additional improvements by Jason Brittain jason.brittain@mulesoft.com.

#

BEGIN INIT INFO

Provides: tomcat7

Required-Start: $local_fs $remote_fs $network

Required-Stop: $local_fs $remote_fs $network

Should-Start: $named

Should-Stop: $named

Default-Start: 2 3 4 5

Default-Stop: 0 1 6

Short-Description: Start Tomcat.

Description: Start the Tomcat servlet engine.

END INIT INFO

set -e

PATH=/bin:/usr/bin:/sbin:/usr/sbin NAME=tomcat7 DESC="Tomcat servlet engine" DEFAULT=/etc/default/$NAME JVM_TMP=/tmp/tomcat7-$NAME-tmp

if [ id -u -ne 0 ]; then echo "You need root privileges to run this script" exit 1 fi

Make sure tomcat is started with system locale

if [ -r /etc/default/locale ]; then . /etc/default/locale export LANG fi

. /lib/lsb/init-functions

if [ -r /etc/default/rcS ]; then . /etc/default/rcS fi

The following variables can be overwritten in $DEFAULT

Run Tomcat 7 as this user ID and group ID

TOMCAT7_USER=tomcat7 TOMCAT7_GROUP=tomcat7

this is a work-around until there is a suitable runtime replacement

for dpkg-architecture for arch:all packages

this function sets the variable OPENJDKS

find_openjdks() { for jvmdir in /usr/lib/jvm/java-7-openjdk- do if [ -d "${jvmdir}" -a "${jvmdir}" != "/usr/lib/jvm/java-7-openjdk-common" ] then OPENJDKS=$jvmdir fi done for jvmdir in /usr/lib/jvm/java-6-openjdk- do if [ -d "${jvmdir}" -a "${jvmdir}" != "/usr/lib/jvm/java-6-openjdk-common" ] then OPENJDKS="${OPENJDKS} ${jvmdir}" fi done }

OPENJDKS="" find_openjdks

The first existing directory is used for JAVA_HOME (if JAVA_HOME is not

defined in $DEFAULT)

JDK_DIRS="/usr/lib/jvm/default-java ${OPENJDKS} /usr/lib/jvm/java-6-openjdk /usr/lib/jvm/java-6-sun"

Look for the right JVM to use

for jdir in $JDK_DIRS; do if [ -r "$jdir/bin/java" -a -z "${JAVA_HOME}" ]; then JAVA_HOME="$jdir" fi done export JAVA_HOME

Directory where the Tomcat 6 binary distribution resides

CATALINA_HOME=/usr/share/$NAME

Directory for per-instance configuration files and webapps

CATALINA_BASE=/var/lib/$NAME

Use the Java security manager? (yes/no)

TOMCAT7_SECURITY=no

Default Java options

Set java.awt.headless=true if JAVA_OPTS is not set so the

Xalan XSL transformer can work without X11 display on JDK 1.4+

It also looks like the default heap size of 64M is not enough for most cases

so the maximum heap size is set to 128M

if [ -z "$JAVA_OPTS" ]; then JAVA_OPTS="-Djava.awt.headless=true -Xmx128M" fi

End of variables that can be overwritten in $DEFAULT

overwrite settings from default file

if [ -f "$DEFAULT" ]; then . "$DEFAULT" fi

if [ ! -f "$CATALINA_HOME/bin/bootstrap.jar" ]; then log_failure_msg "$NAME is not installed" exit 1 fi

POLICY_CACHE="$CATALINA_BASE/work/catalina.policy"

if [ -z "$CATALINA_TMPDIR" ]; then CATALINA_TMPDIR="$JVM_TMP" fi

Set the JSP compiler if set in the tomcat7.default file

if [ -n "$JSP_COMPILER" ]; then JAVA_OPTS="$JAVA_OPTS -Dbuild.compiler=\"$JSP_COMPILER\"" fi

SECURITY="" if [ "$TOMCAT7_SECURITY" = "yes" ]; then SECURITY="-security" fi

Define other required variables

CATALINA_PID="/var/run/$NAME.pid" CATALINA_SH="$CATALINA_HOME/bin/catalina.sh"

Look for Java Secure Sockets Extension (JSSE) JARs

if [ -z "${JSSE_HOME}" -a -r "${JAVA_HOME}/jre/lib/jsse.jar" ]; then JSSE_HOME="${JAVA_HOME}/jre/" fi

catalina_sh() {

Escape any double quotes in the value of JAVA_OPTS

JAVA_OPTS="$(echo $JAVA_OPTS | sed 's/\"/\\"/g')"

AUTHBIND_COMMAND=""
if [ "$AUTHBIND" = "yes" -a "$1" = "start" ]; then
    JAVA_OPTS="$JAVA_OPTS -Djava.net.preferIPv4Stack=true"
    AUTHBIND_COMMAND="/usr/bin/authbind --deep /bin/bash -c "
fi

# Define the command to run Tomcat's catalina.sh as a daemon
# set -a tells sh to export assigned variables to spawned shells.
TOMCAT_SH="set -a; JAVA_HOME=\"$JAVA_HOME\"; source \"$DEFAULT\"; \
    CATALINA_HOME=\"$CATALINA_HOME\"; \
    CATALINA_BASE=\"$CATALINA_BASE\"; \
    JAVA_OPTS=\"$JAVA_OPTS\"; \
    CATALINA_PID=\"$CATALINA_PID\"; \
    CATALINA_TMPDIR=\"$CATALINA_TMPDIR\"; \
    LANG=\"$LANG\"; JSSE_HOME=\"$JSSE_HOME\"; \
    cd \"$CATALINA_BASE\"; \
    \"$CATALINA_SH\" $@"

if [ "$AUTHBIND" = "yes" -a "$1" = "start" ]; then
    TOMCAT_SH="'$TOMCAT_SH'"
fi

# Run the catalina.sh script as a daemon
set +e
touch "$CATALINA_PID" "$CATALINA_BASE"/logs/catalina.out
chown $TOMCAT7_USER "$CATALINA_PID" "$CATALINA_BASE"/logs/catalina.out
start-stop-daemon --start -b -u "$TOMCAT7_USER" -g "$TOMCAT7_GROUP" \
    -c "$TOMCAT7_USER" -d "$CATALINA_TMPDIR" -p "$CATALINA_PID" \
    -x /bin/bash -- -c "$AUTHBIND_COMMAND $TOMCAT_SH"
status="$?"
set +a -e
return $status

}

case "$1" in start) if [ -z "$JAVA_HOME" ]; then log_failure_msg "no JDK found - please set JAVA_HOME" exit 1 fi

if [ ! -d "$CATALINA_BASE/conf" ]; then
    log_failure_msg "invalid CATALINA_BASE: $CATALINA_BASE"
    exit 1
fi

log_daemon_msg "Starting $DESC" "$NAME"
if start-stop-daemon --test --start --pidfile "$CATALINA_PID" \
    --user $TOMCAT7_USER --exec "$JAVA_HOME/bin/java" \
    >/dev/null; then

    # Regenerate POLICY_CACHE file
    umask 022
    echo "// AUTO-GENERATED FILE from /etc/tomcat7/policy.d/" \
        > "$POLICY_CACHE"
    echo ""  >> "$POLICY_CACHE"
    cat $CATALINA_BASE/conf/policy.d/*.policy \
        >> "$POLICY_CACHE"

    # Remove / recreate JVM_TMP directory
    rm -rf "$JVM_TMP"
    mkdir -p "$JVM_TMP" || {
        log_failure_msg "could not create JVM temporary directory"
        exit 1
    }
    chown $TOMCAT7_USER "$JVM_TMP"

    catalina_sh start $SECURITY
    sleep 5
        if start-stop-daemon --test --start --pidfile "$CATALINA_PID" \
        --user $TOMCAT7_USER --exec "$JAVA_HOME/bin/java" \
        >/dev/null; then
        if [ -f "$CATALINA_PID" ]; then
            rm -f "$CATALINA_PID"
        fi
        log_end_msg 1
    else
        log_end_msg 0
    fi
else
        log_progress_msg "(already running)"
    log_end_msg 0
fi
;;

stop) log_daemon_msg "Stopping $DESC" "$NAME"

set +e
if [ -f "$CATALINA_PID" ]; then 
    start-stop-daemon --stop --pidfile "$CATALINA_PID" \
        --user "$TOMCAT7_USER" \
        --retry=TERM/20/KILL/5 >/dev/null
    if [ $? -eq 1 ]; then
        log_progress_msg "$DESC is not running but pid file exists, cleaning up"
    elif [ $? -eq 3 ]; then
        PID="`cat $CATALINA_PID`"
        log_failure_msg "Failed to stop $NAME (pid $PID)"
        exit 1
    fi
    rm -f "$CATALINA_PID"
    rm -rf "$JVM_TMP"
else
    log_progress_msg "(not running)"
fi
log_end_msg 0
set -e
;;

status) set +e start-stop-daemon --test --start --pidfile "$CATALINA_PID" \ --user $TOMCAT7_USER --exec "$JAVA_HOME/bin/java" \

/dev/null 2>&1 if [ "$?" = "0" ]; then

    if [ -f "$CATALINA_PID" ]; then
        log_success_msg "$DESC is not running, but pid file exists."
        exit 1
    else
        log_success_msg "$DESC is not running."
        exit 3
    fi
else
    log_success_msg "$DESC is running with pid `cat $CATALINA_PID`"
fi
set -e
    ;;

restart|force-reload) if [ -f "$CATALINA_PID" ]; then $0 stop sleep 1 fi $0 start ;; try-restart) if start-stop-daemon --test --start --pidfile "$CATALINA_PID" \ --user $TOMCAT7_USER --exec "$JAVA_HOME/bin/java" \

/dev/null; then $0 start fi ;; *) log_success_msg "Usage: $0 {start|stop|restart|try-restart|force-reload|status}" exit 1 ;; esac

exit 0

[radut]

search for : TOMCAT7_USER=tomcat7 TOMCAT7_GROUP=tomcat7 and change to TOMCAT7_USER=root TOMCAT7_GROUP=root

[hemachowdary]

i changed TOMCAT7_USER=root TOMCAT7_GROUP=root

but still i am getting same issue

[radut]

ps -ef | grep java has 'root' in first column ?

[hemachowdary]

no it is having pi pi 2635 2228 0 09:01 pts/0 00:00:00 grep --color=auto java

[hemachowdary]

complete output of that command tomcat7 2588 1 42 08:54 ? 00:02:46 /usr/lib/jvm/java-7-openjdk-armhf/bin/java -Djava.util.logging.config.file=/var/lib/tomcat7/conf/logging.properties -Djava.awt.headless=true -Xmx128m -XX:+UseConcMarkSweepGC -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.endorsed.dirs=/usr/share/tomcat7/endorsed -classpath /usr/share/tomcat7/bin/bootstrap.jar:/usr/share/tomcat7/bin/tomcat-juli.jar -Dcatalina.base=/var/lib/tomcat7 -Dcatalina.home=/usr/share/tomcat7 -Djava.io.tmpdir=/tmp/tomcat7-tomcat7-tmp org.apache.catalina.startup.Bootstrap start pi 2635 2228 0 09:01 pts/0 00:00:00 grep --color=auto java

[radut]

no, it's stil tomcat7, the line with /usr/lib/jvm... must be followed can we move this discussion to somewhere else, like gtalk ?

[hemachowdary]

sorry to say , i am at office i cant come to gtalk.

[radut]

ok stop tomcat

cd /usr/share/tomcat7/bin sudo su (check if user is root) id ./catalina.sh then again ps -ef | grep java

[hemachowdary]

[ ok ] Stopping Tomcat servlet engine: tomcat7. pi@raspberrypi ~ $ cd /usr/share/tomcat7/bin pi@raspberrypi /usr/share/tomcat7/bin $ sudo su root@raspberrypi:/usr/share/tomcat7/bin# id uid=0(root) gid=0(root) groups=0(root),1001(indiecity),1003(gpio) root@raspberrypi:/usr/share/tomcat7/bin# ./catailna.sh bash: ./catailna.sh: No such file or directory

i think user is root only pl find the above lines for your reference

[radut]

ok you are root but you don't have catalina.sh in bin directory what's the listing of that directory ? ls

[hemachowdary]

bootstrap.jar configtest.sh setclasspath.sh tomcat-juli.jar catalina.sh daemon.sh shutdown.sh tool-wrapper.sh catalina-tasks.xml digest.sh startup.sh version.sh

[radut]

you wrote catailna.sh when it's catalina.sh , use TAB for auto complete

by the way, I see that root is in group gpio, maybe it is easyer to add tomcat7 to group gpio run as sudo usermod -a -G gpio tomcat7 and start the service again

[hemachowdary]

i follwed above steps now there is some change in error

Unable to open GPIO direction interface for pin [0]: Permission denied

[radut]

and now you are running tomcat as user ...tomcat7 ? still permission.. stop tomcat, and try again running ./catalina.sh check what user is running java as root should work, and have no permission problems.

[hemachowdary]

this is the output i am getting

pi@raspberrypi ~ $ cd /usr/share/tomcat7/bin pi@raspberrypi /usr/share/tomcat7/bin $ sudo su root@raspberrypi:/usr/share/tomcat7/bin# ./catalina.sh Using CATALINA_BASE: /usr/share/tomcat7 Using CATALINA_HOME: /usr/share/tomcat7 Using CATALINA_TMPDIR: /usr/share/tomcat7/temp Using JRE_HOME: /usr/lib/jvm/java-1.7.0-openjdk-armhf Using CLASSPATH: /usr/share/tomcat7/bin/bootstrap.jar:/usr/share/tomcat7/bin/tomcat-juli.jar Usage: catalina.sh ( commands ... ) commands: debug Start Catalina in a debugger debug -security Debug Catalina with a security manager jpda start Start Catalina under JPDA debugger run Start Catalina in the current window run -security Start in the current window with security manager start Start Catalina in a separate window start -security Start in a separate window with security manager stop Stop Catalina, waiting up to 5 seconds for the process to end stop n Stop Catalina, waiting up to n seconds for the process to end stop -force Stop Catalina, wait up to 5 seconds and then use kill -KILL if still running stop n -force Stop Catalina, wait up to n seconds and then use kill -KILL if still running configtest Run a basic syntax check on server.xml - check exit code for result version What version of tomcat are you running? Note: Waiting for the process to end and use of the -force option require that $CATALINA_PID is defined

[hemachowdary]

should i changed this TOMCAT7_USER=root TOMCAT7_GROUP=root

back to

TOMCAT7_USER=tomcat7 TOMCAT7_GROUP=tomcat7

[radut]

./catalina.sh start

[hemachowdary]

Using CATALINA_BASE: /usr/share/tomcat7 Using CATALINA_HOME: /usr/share/tomcat7 Using CATALINA_TMPDIR: /usr/share/tomcat7/temp Using JRE_HOME: /usr/lib/jvm/java-1.7.0-openjdk-armhf Using CLASSPATH: /usr/share/tomcat7/bin/bootstrap.jar:/usr/share/tomcat7/bin/tomcat-juli.jar touch: cannot touch `/usr/share/tomcat7/logs/catalina.out': No such file or directory ./catalina.sh: 389: ./catalina.sh: cannot create /usr/share/tomcat7/logs/catalina.out: Directory nonexistent

i am getting directory not existent find the above output for your reference..