Application Packaging Developer's Guide

Example--Analysis Scripts That Walk a BASEDIR

Assume that the x86 version of SUNWstuf is already installed on the server in /opt/SUNWstuf. When the administrator uses the pkgadd command to install the SPARC version, the request script needs to detect the existence of the x86 version and interact with the administrator regarding the installation.


Note -

The base directory could be walked without administrator interaction in a checkinstall script, but if arbitrary operations like this happen too often, administrators lose confidence in the process.


The request script and checkinstall script for a package that handle this situation might look like this.

The request Script

# request script
for SUNWstuf to walk the BASEDIR parameter.

PATH=/usr/sadm/bin:${PATH}	# use admin utilities

GENMSG="The base directory $LOCAL_BASE already contains a \
different architecture or version of $PKG."

OLDMSG="If the option \"-a none\" was used, press the  \
key and enter an unused base directory when it is requested."

OLDPROMPT="Do you want to overwrite this version? "

OLDHELP="\"y\" will replace the installed package, \"n\" will \
stop the installation."

SUSPEND="Suspending installation at user request using error \
code 1."

MSG="This package could be installed at the unused base directory $WRKNG_BASE."

PROMPT="Do you want to use to the proposed base directory? "

HELP="A response of \"y\" will install to the proposed directory and continue,
\"n\" will request a different directory. If the option \"-a none\" was used,
press the  key and enter an unused base directory when it is requested."

DIRPROMPT="Select a preferred base directory ($WRKNG_BASE) "

DIRHELP="The package $PKG will be installed at the location entered."

NUBD_MSG="The base directory has changed. Be sure to update \
any applicable search paths with the actual location of the \
binaries which are at $WRKNG_BASE/EZstuf and $WRKNG_BASE/HRDstuf."

OldSolaris=""
Changed=""
Suffix="0"

#
# Determine if this product is actually installed in the working
# base directory.
#
Product_is_present () {
	  if [ -d $WRKNG_BASE/EZstuf -o -d $WRKNG_BASE/HRDstuf ]; then
		    return 1
	  else
		    return 0
	  fi
}

if [ ${BASEDIR} ]; then
	  # This may be an old version of Solaris. In the latest Solaris
	  # CLIENT_BASEDIR won't be defined yet. In older version it is.
	  if [ ${CLIENT_BASEDIR} ]; then
		    LOCAL_BASE=$BASEDIR
		    OldSolaris="true"
	  else	# The base directory hasn't been processed yet
		    LOCAL_BASE=${PKG_INSTALL_ROOT}$BASEDIR
fi

WRKNG_BASE=$LOCAL_BASE

	# See if the base directory is already in place and walk it if
	# possible
while [ -d ${WRKNG_BASE} -a Product_is_present ]; do
		 # There is a conflict
		 # Is this an update of the same arch & version?
		 if [ ${UPDATE} ]; then
			   exit 0	# It's out of our hands.
		 else
			   # So this is a different architecture or
			   # version than what is already there.
			   # Walk the base directory
			   Suffix=`expr $Suffix + 1`
			   WRKNG_BASE=$LOCAL_BASE.$Suffix
			   Changed="true"
		 fi
done

	# So now we can propose a base directory that isn't claimed by
	# any of our other versions.
if [ $Changed ]; then
		 puttext "$GENMSG"
		 if [ $OldSolaris ]; then
			   puttext "$OLDMSG"
			   result=`ckyorn -Q -d "a" -h "$OLDHELP" -p "$OLDPROMPT"`
			   if [ $result="n" ]; then
				     puttext "$SUSPEND"
				     exit 1	# suspend installation
			   else
				     exit 0
			   fi
		 else	# The latest functionality is available
			   puttext "$MSG"
			   result=`ckyorn -Q -d "a" -h "$HELP" -p "$PROMPT"`
			   if [ $? -eq 3]; then
				     echo quitinstall >> $1
				     exit 0
			   fi

			   if [ $result="n" ]; then
				     WRKNG_BASE=`ckpath -ayw -d "$WRKNG_BASE" \
				     -h "$DIRHELP" -p "$DIRPROMPT"`
			   else if [ $result="a" ]
				     exit 0
			   fi
		    fi
		    echo "BASEDIR=$WRKNG_BASE" >> $1
		    puttext "$NUBD_MSG"
	  fi
fi
exit 0

The checkinstall Script

# checkinstall
script for SUNWstuf to politely suspend

grep quitinstall $1
if [ $? -eq 0 ]; then
	exit 3		# politely suspend installation
fi

exit 0

This approach would not work very well if the base directory was simply /opt. This package has to call out the BASEDIR more precisely since /opt would be difficult to walk. In fact, depending on the mount scheme, it may not be possible. The example walks the base directory by creating a new directory under /opt, which does not introduce any problems.

This example uses a request script and a checkinstall script even though versions of Solaris prior to the 2.5 release cannot run a checkinstall script. The checkinstall script in this example is used for the purpose of politely halting the installation in response to a private message in the form of the string "quitinstall." If this script executes under the Solaris 2.3 release, the checkinstall script is ignored and the request script halts the installation with an error message.

Remember that prior to the Solaris 2.5 and compatible releases, the BASEDIR parameter is a read-only parameter and cannot be changed by the request script. For this reason, if an old version of the SunOS operating system is detected (by testing for a conditioned CLIENT_BASEDIR environment variable), the request script has only two options--continue or quit.