Handle case where become script is unreadable.

[profile.git] / opt / bin / become

diff --git a/opt/bin/become b/opt/bin/become
index 0825bd6..ea4926d 100755 (executable)
--- a/opt/bin/become
+++ b/opt/bin/become
@@ -3,21 +3,29 @@
 chdir=0
 kerberos=0
 x11=0
-while getopts ":kx" opt; do
+dir=
+while getopts ":cd:kx" opt; do
   case $opt in
     c) chdir=1;;
+    d) dir=$OPTARG;;
     k) kerberos=1;;
     x) x11=1;;
   esac
 done
 shift $((OPTIND-1))
 
+if [ -z "$dir" ]; then
+  dir=${0%/*}
+  [ "$dir" = "$0" -o "$dir" = "." ] && dir=$PWD
+fi
+
 user="$1"; shift
 if [ -z "$user" ]; then
-  echo >&2 "Usage: become [-c] [-k] [-x] <user>"
-  echo >&2 "Options: -c   Stay in current directory even if target user is not root."
-  echo >&2 "         -k   Delegate Kerberos credentials even if target user is not root."
-  echo >&2 "         -x   Delegate X11 cookie even if target user is not root."
+  echo >&2 "Usage: become [-c] [-d <dir>] [-k] [-x] <user>"
+  echo >&2 "Options: -c         Stay in current directory even if target user is not root."
+  echo >&2 "         -d <dir>   Look for \"became\" script in given directory."
+  echo >&2 "         -k         Delegate Kerberos credentials even if target user is not root."
+  echo >&2 "         -x         Delegate X11 cookie even if target user is not root."
   exit 1
 fi
 
@@ -37,9 +45,50 @@ PRINCIPAL=$(klist 2>/dev/null | sed -n 's/^Default principal: //p')
 if [ $x11 = 1 -a -n "$DISPLAY" -a "${DISPLAY##localhost:}" = "$DISPLAY" ]; then
   COOKIE="$(xauth list $DISPLAY)"
 fi
-BECOME="$HOME/.become"
-profile="$BECOME/$user"
-[ -f "$profile" ] || profile="$BECOME/all"
+ignore_profile_user=0
+for candidate in "$HOME" "$PROFILE_HOME"; do
+  [ -n "$candidate" ] || continue
+  BECOME="$candidate/.become"
+  [ -d "$BECOME" ] || continue
+
+  # Script to run when becoming any user.
+  [ -z "$allusersprofile" ] && allusersprofile="$BECOME/all"
+  [ -f "$allusersprofile" ] || allusersprofile=
+
+  # Set $HOME/all sticky to ignore $PROFILE_HOME/$user.
+  if [ "$candidate" = "$HOME" ]; then
+    [ -k "$BECOME/all" ] && ignore_profile_user=1
+  else
+    [ $ignore_profile_user = 1 ] && continue
+  fi
+
+  # Script to run (after the one mentioned above) when becoming this user.
+  [ -z "$userprofile" ] && userprofile="$BECOME/$user"
+  [ -f "$userprofile" ] || userprofile=
+done
+
+# Preserve environment variables.
+ignore_environment_user=0
+for candidate in "$HOME" "$PROFILE_HOME"; do
+  [ -n "$candidate" ] || continue
+  BECOME="$candidate/.become/environment"
+  [ -d "$BECOME" ] || continue
+
+  # Script to run when becoming any user.
+  [ -z "$allusersenvironment" ] && allusersenvironment="$BECOME/all"
+  [ -f "$allusersenvironment" ] || allusersenvironment=
+
+  # Set $HOME/all sticky to ignore $PROFILE_HOME/$user.
+  if [ "$candidate" = "$HOME" ]; then
+    [ -k "$BECOME/all" ] && ignore_environment_user=1
+  else
+    [ $ignore_environment_user = 1 ] && continue
+  fi
+
+  # Environment variables to preserve when becomeing this user.
+  [ -z "$userenvironment" ] && userenvironment="$BECOME/$user"
+  [ -f "$userenvironment" ] || userenvironment=
+done
 
 file="${TMPDIR:-/tmp}/$USER.become.$user.$RANDOM.$$"
 umask=$(builtin umask -p)
@@ -47,7 +96,7 @@ builtin umask 077
 if exec 3>"$file" && exec <"$file" && rm "$file"; then
   builtin $umask
   echo >&3 "cd"
-  echo >&3 "PROFILE_HOME='$HOME'"
+  echo >&3 "PROFILE_HOME='${PROFILE_HOME:-$HOME}'"
   if [ -n "$PRINCIPAL" ]; then
     echo >&3 "PRINCIPAL='$PRINCIPAL'"
     if [ $kerberos = 1 ]; then
@@ -67,17 +116,26 @@ if exec 3>"$file" && exec <"$file" && rm "$file"; then
   else
     echo >&3 "unset DISPLAY"
   fi
+  if [ ! "$PROFILE_HOME" = "$HOME" ]; then
+    echo >&3 "export SCREENRC=$PROFILE_HOME/.screenrc"
+  fi
 else
   exit 111
 fi
 
-echo >&3 ". $HOME/.bash_profile"
-[ -f "$BECOME/all" ] && cat >&3 2>/dev/null "$BECOME/all"
-[ -f "$BECOME/$user" ] && cat >&3 2>/dev/null "$BECOME/$user"
+echo >&3 ". ${PROFILE_HOME:-$HOME}/.bash_profile"
+for profile in "$allusersprofile" "$userprofile"; do
+  [ -f "$profile" ] && cat >&3 2>/dev/null "$profile"
+done
+for environment in "$allusersenvironment" "$userenvironment"; do
+  [ -f "$environment" ] || continue
+  while read -d $'\n' variable; do
+    variable=${variable%%=*}
+    eval "[ -z \${$variable:+set} ] || echo >&3 \"$variable='\$$variable'\""
+  done < "$environment"
+done
 [ $chdir = 1 ] && echo >&3 2>/dev/null "cd - &>/dev/null"
 
 exec 3>&-
-dir=$(dirname "$0")
-[ "$dir" = "." ] && dir="$PWD"
 exec sudo -H -u "$user" "$dir/became"
 exit 111