[thisroot] resolve symbolic links

- Use dirname and realpath to resolve symbolic links of thisroot.sh to find the root installation.
- Print error message if thisroot.sh is not part of a root installation
- Do the same for csh and fish

Fixes https://its.cern.ch/jira/browse/ROOT-10415

Co-authored-by: Stephan Hageboeck <[email protected]>

Author: ferdymercury

config/thisroot.csh

@@ -17,29 +17,31 @@ endif
 set ARGS=($_)
 
 set LSOF=`env PATH=/usr/sbin:${PATH} which lsof`
-set thisfile="`${LSOF} -w +p $$ | grep -oE '/.*thisroot.csh'  `"
-if ( "$thisfile" == "" ) then
-#   set thisfile=/does/not/exist
+set SOURCE="`${LSOF} -w +p $$ | grep -oE '/.*thisroot.csh'  `"
+if ( "$SOURCE" == "" ) then
+#   set SOURCE=/does/not/exist
 endif
-if ( "$thisfile" != "" && -e ${thisfile} ) then
+if ( "$SOURCE" != "" && -e ${SOURCE} ) then
    # We found it, didn't we.
-   set thisroot="`dirname ${thisfile}`"
+   set SOURCE=`realpath ${SOURCE}`
+   set thisrootdir=`dirname ${SOURCE}`
 else if ("$ARGS" != "") then
-   set thisroot="`dirname ${ARGS[2]}`"
+   set SOURCE=`realpath ${ARGS[2]}`
+   set thisrootdir="`dirname ${SOURCE}`"
 else
    # But $_ might not be set if the script is source non-interactively.
    # In [t]csh the sourced file is inserted 'in place' inside the
    # outer script, so we need an external source of information
    # either via the current directory or an extra parameter.
    if ( -e thisroot.csh ) then
-      set thisroot=${PWD}
+      set thisrootdir=${PWD}
    else if ( -e bin/thisroot.csh ) then
-      set thisroot=${PWD}/bin
+      set thisrootdir=${PWD}/bin
    else if ( "$1" != "" ) then
       if ( -e ${1}/bin/thisroot.csh ) then
-         set thisroot=${1}/bin
+         set thisrootdir=${1}/bin
       else if ( -e ${1}/thisroot.csh ) then
-         set thisroot=${1}
+         set thisrootdir=${1}
       else
          echo "thisroot.csh: ${1} does not contain a ROOT installation"
       endif
@@ -53,9 +55,14 @@ else
    endif
 endif
 
-if ($?thisroot) then
+if ($?thisrootdir) then
 
-setenv ROOTSYS "`(cd ${thisroot}/..;pwd)`"
+setenv ROOTSYS "`(dirname ${thisrootdir})`"
+if ( ! -f "$ROOTSYS/bin/root-config" ) then
+    echo "ERROR: root-config not found under ROOTSYS=\"$ROOTSYS/\"" >&2
+    set ROOTSYS =
+    return 1
+endif
 
 if ($?old_rootsys) then
    setenv PATH `set DOLLAR='$'; echo $PATH | sed -e "s;:$old_rootsys/bin:;:;g" \
@@ -232,7 +239,7 @@ else
    setenv JUPYTER_CONFIG_PATH ${ROOTSYS}/etc/notebook
 endif
 
-endif # if ("$thisroot" != "")
+endif # if ("$thisrootdir" != "")
 
-set thisroot=
+set thisrootdir=
 set old_rootsys=

config/thisroot.fish

@@ -29,8 +29,14 @@ end
 
 set SOURCE (status -f)
 # normalize path
-set thisroot (path dirname $SOURCE)
-set -xg ROOTSYS (set oldpwd $PWD; cd $thisroot/.. > /dev/null;pwd;cd $oldpwd; set -e oldpwd)
+set thisrootdir (dirname (realpath $SOURCE))
+set -xg ROOTSYS (string replace -r '/[^/]*$' '' $thisrootdir)
+
+if not test -f "$ROOTSYS/bin/root-config"
+    echo "ERROR: root-config not found under ROOTSYS=\"$ROOTSYS/\"" >&2
+    set -e ROOTSYS
+    exit
+end
 
 if not set -q MANPATH
    # Grab the default man path before setting the path to avoid duplicates

config/thisroot.sh

@@ -244,15 +244,15 @@ if [ -z "${SOURCE}" ]; then
       return 1
    fi
 else
-   # get param to "."
-   thisroot="$(dirname "${SOURCE}")"
-   ROOTSYS=$(cd "${thisroot}/.." > /dev/null && pwd); export ROOTSYS
-   if [ -z "$ROOTSYS" ]; then
-      echo "ERROR: \"cd ${thisroot}/..\" or \"pwd\" failed" >&2
-      return 1
-   fi
+   thisrootdir=$(dirname $(realpath "${SOURCE}"))
+   export ROOTSYS=${thisrootdir%/*}
 fi
 
+if ! [ -f "${ROOTSYS}/bin/root-config" ] ; then
+   echo "ERROR: root-config not found under ROOTSYS=\"${ROOTSYS}/\"" >&2
+   ROOTSYS=; export ROOTSYS
+   return 1
+fi
 
 clean_environment
 set_environment