Remove bashismes from ejabberdctl

To avoid unecessary extra quoting, do not call commands with sh -c ''
and use the -- option from su to supply arguments.

Parse command line parameters is a bit tricky as the previous behavior
allows to mix options to ejabberdctl with unknown options given to
the next script (usually, the ctl). This is solved by relying on the
fact that for loop saves its argument, so we can flush its content
with set -- and re-add unknown options with set -- "$@" "$arg".

Finally, remove unecessary quotes in mnesia options and in the ping
command.

ejabberdctl.template

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 
 # define default configuration
 POLL=true
@@ -27,35 +27,59 @@ if [ "$INSTALLUSER" != "" ] ; then
                 mkdir -p "$INSTALLUSER_HOME"
                 chown "$INSTALLUSER" "$INSTALLUSER_HOME"
             fi
-            EXEC_CMD="su $INSTALLUSER -c"
+            EXEC_CMD="as_install_user"
         fi
     done
     if [ `id -g` -eq `id -g $INSTALLUSER` ] ; then
-        EXEC_CMD="bash -c"
+        EXEC_CMD="as_current_user"
     fi
     if [ "$EXEC_CMD" = "false" ] ; then
         echo "This command can only be run by root or the user $INSTALLUSER" >&2
         exit 4
     fi
 else
-    EXEC_CMD="bash -c"
+    EXEC_CMD="as_current_user"
 fi
 
+# run command either directly or via su $INSTALLUSER
+exec_cmd()
+{
+    if [ "EXEC_CMD" = as_install_user ]; then
+        su -c '"$0" $@"' "INSTALLUSER" -- "$@"
+    else
+        "$@"
+    fi
+}
+
 # parse command line parameters
-declare -a ARGS=()
+next=init
-while [ $# -ne 0 ] ; do
+for arg; do
-    PARAM="$1"
+    # Empty argument list as it is already saved in the for buffer
-    shift
+    if [ "$next" = init ]; then
-    case $PARAM in
+        next=
-        --) break ;;
+        set --
+    fi
+    case $next in
+        node) ERLANG_NODE_ARG=$arg; next=;;
+        config-dir) ETC_DIR=$arg; next=;;
+        config) EJABBERD_CONFIG_PATH=$arg; next=;;
+        ctl-config) EJABBERDCTL_CONFIG_PATH=$arg; next=;;
+        logs) LOGS_DIR=$arg; next=;;
+        spool) SPOOL_DIR=$arg; next=;;
+        "")
+            case $arg in
+                --) next=raw;;
                 --no-timeout) EJABBERD_NO_TIMEOUT="--no-timeout" ;;
-        --node) ERLANG_NODE_ARG=$1 ; shift ;;
+                --node) next=node;;
-        --config-dir) ETC_DIR="$1" ; shift ;;
+                --config-dir) next=config-dir;;
-        --config) EJABBERD_CONFIG_PATH="$1" ; shift ;;
+                --config) next=config;;
-        --ctl-config) EJABBERDCTL_CONFIG_PATH="$1" ; shift ;;
+                --ctl-config) next=ctl-config;;
-        --logs) LOGS_DIR="$1" ; shift ;;
+                --logs) next=logs;;
-        --spool) SPOOL_DIR="$1" ; shift ;;
+                --spool) next=spool;;
-        *) ARGS=("${ARGS[@]}" "$PARAM") ;;
+                *) set -- "$@" "$arg";; # unknown option, keep it.
+            esac;;
+        raw) # we are after --, keep options as it is.
+            set -- "$@" "$arg";;
     esac
 done
 
@@ -93,7 +117,7 @@ ERL_CRASH_DUMP=$LOGS_DIR/erl_crash_$DATETIME.dump
 ERL_INETRC=$ETC_DIR/inetrc
 
 # define mnesia options
-MNESIA_OPTS="-mnesia dir \"\\\"$SPOOL_DIR\\\"\" $MNESIA_OPTIONS"
+MNESIA_OPTS="-mnesia dir \"$SPOOL_DIR\" $MNESIA_OPTIONS"
 # define erl parameters
 ERLANG_OPTS="+K $POLL -smp $SMP +P $ERL_PROCESSES $ERL_OPTIONS"
 KERNEL_OPTS=""
@@ -150,40 +174,20 @@ export CONTRIB_MODULES_PATH
 export CONTRIB_MODULES_CONF_DIR
 export ERL_LIBS
 
-shell_escape_str()
+# TODO: Too much copy-and-paste below, factorize!
-{
-    if test $# -eq 0; then
-        printf '"" '
-    else
-        shell_escape "$@"
-    fi
-}
-
-shell_escape()
-{
-    local RES=()
-    for i in "$@"; do
-        if test -z "$i"; then
-            printf '"" '
-        else
-            printf '%q ' "$i"
-        fi
-    done
-}
-
 # start server
 start()
 {
     check_start
-    CMD="`shell_escape \"$ERL\" \"$NAME\" \"$ERLANG_NODE\"` \
+    exec_cmd $ERL \
+             $NAME $ERLANG_NODE \
              -noinput -detached \
              $MNESIA_OPTS \
              $KERNEL_OPTS \
              $EJABBERD_OPTS \
              -s ejabberd \
              $ERLANG_OPTS \
-         `shell_escape \"${ARGS[@]}\" \"$@\"`"
+             "$@"
-    $EXEC_CMD "$CMD"
 }
 
 # attach to server
@@ -191,13 +195,12 @@ debug()
 {
     debugwarning
     NID=$(uid debug)
-    CMD="`shell_escape \"$ERL\" \"$NAME\" \"$NID\"` \
+    exec_cmd $ERL $NAME $NID \
              -remsh $ERLANG_NODE \
              -hidden \
              $KERNEL_OPTS \
              $ERLANG_OPTS \
-         `shell_escape \"${ARGS[@]}\" \"$@\"`"
+             "$@"
-    $EXEC_CMD "$CMD"
 }
 
 # attach to server using Elixir
@@ -206,27 +209,24 @@ iexdebug()
     debugwarning
     # Elixir shell is hidden as default
     NID=$(uid debug)
-    CMD="`shell_escape \"$IEX\" \"$IEXNAME\" \"$NID\"` \
+    exec_cmd $IEX $IEXNAME $NID \
-         -remsh $ERLANG_NODE \
+             -remsh "$ERLANG_NODE" \
-         --erl `shell_escape \"$KERNEL_OPTS\"` \
+             --erl "$KERNEL_OPTS" \
-         --erl `shell_escape \"$ERLANG_OPTS\"` \
+             --erl "$ERLANG_OPTS" \
-         --erl `shell_escape \"${ARGS[@]}\"` \
+             --erl "$@"
-         --erl `shell_escape_str \"$@\"`"
-    $EXEC_CMD "ERL_PATH=\"$ERL\" $CMD"
 }
 
 # start interactive server
 live()
 {
     livewarning
-    CMD="`shell_escape \"$ERL\" \"$NAME\" \"${ERLANG_NODE}\"` \
+    exec_cmd $ERL $NAME $ERLANG_NODE \
              $MNESIA_OPTS \
              $KERNEL_OPTS \
              $EJABBERD_OPTS \
              -s ejabberd \
              $ERLANG_OPTS \
-         `shell_escape \"${ARGS[@]}\" \"$@\"`"
+             "$@"
-    $EXEC_CMD "$CMD"
 }
 
 # start interactive server with Elixir
@@ -234,30 +234,27 @@ iexlive()
 {
     livewarning
     echo $@
-    CMD="`shell_escape \"$IEX\" \"$IEXNAME\" \"${ERLANG_NODE}\"` \
+    exec_cmd $IEX $IEXNAME $ERLANG_NODE \
-         --erl \"-mnesia dir \\\"$SPOOL_DIR\\\"\" \
+         --erl "-mnesia dir \"$SPOOL_DIR\"" \
-         --erl \"`shell_escape \"$KERNEL_OPTS\"`\" \
+         --erl "$KERNEL_OPTS" \
-         --erl \"`shell_escape \"$EJABBERD_OPTS\"`\" \
+         --erl "$EJABBERD_OPTS" \
          --app ejabberd \
-         --erl `shell_escape \"$ERLANG_OPTS\"` \
+         --erl "$ERLANG_OPTS" \
-         --erl `shell_escape \"${ARGS[@]}\"` \
+         --erl "$@"
-         --erl `shell_escape_str \"$@\"`"
-    $EXEC_CMD "ERL_PATH=\"$ERL\" $CMD"
 }
 
 # start server in the foreground
 foreground()
 {
     check_start
-    CMD="`shell_escape \"$ERL\" \"$NAME\" \"$ERLANG_NODE\"` \
+    exec_cmd $ERL $NAME $ERLANG_NODE \
          -noinput \
          $MNESIA_OPTS \
          $KERNEL_OPTS \
          $EJABBERD_OPTS \
          -s ejabberd \
          $ERLANG_OPTS \
-         `shell_escape \"${ARGS[@]}\" \"$@\"`"
+         "$@"
-    $EXEC_CMD "$CMD"
 }
 
 debugwarning()
@@ -311,9 +308,9 @@ livewarning()
 etop()
 {
     NID=$(uid top)
-    $EXEC_CMD "$ERL \
+    exec_cmd $ERL \
       $NAME $NID \
-      -hidden -s etop -s erlang halt -output text -node $ERLANG_NODE"
+      -hidden -s etop -s erlang halt -output text -node $ERLANG_NODE
 }
 
 ping()
@@ -327,11 +324,11 @@ ping()
         PING_NODE=$(hostname)
     fi
     NID=$(uid ping ${PING_NODE})
-    $EXEC_CMD "$ERL \
+    exec_cmd $ERL \
              $PING_NAME $NID \
              -hidden $KERNEL_OPTS $ERLANG_OPTS \
-      -eval 'io:format(\"~p~n\",[net_adm:ping('\"'\"'$PEER'\"'\"')])' \
+             -eval 'io:format("~p~n",[net_adm:ping('"$PEER"')])' \
-      -s erlang halt -output text -noinput"
+             -s erlang halt -output text -noinput
 }
 
 help()
@@ -359,11 +356,10 @@ help()
 ctl()
 {
     NID=$(uid ctl)
-    CMD="`shell_escape \"$ERL\" \"$NAME\" \"$NID\"` \
+    exec_cmd $ERL $NAME $NID \
          -noinput -hidden $KERNEL_OPTS -s ejabberd_ctl \
-         -extra `shell_escape \"$ERLANG_NODE\"` $EJABBERD_NO_TIMEOUT \
+         -extra $ERLANG_NODE $EJABBERD_NO_TIMEOUT \
-         `shell_escape \"$@\"`"
+         "$@"
-    $EXEC_CMD "$CMD"
     result=$?
     case $result in
         2) help;;
@@ -376,7 +372,8 @@ ctl()
 uid()
 {
     uuid=$(uuidgen 2>/dev/null)
-    [ -z "$uuid" -a -f /proc/sys/kernel/random/uuid ] && uuid=$(</proc/sys/kernel/random/uuid)
+    [ -z "$uuid" -a -f /proc/sys/kernel/random/uuid ] && \
+        uuid=$(cat /proc/sys/kernel/random/uuid)
     [ -z "$uuid" ] && uuid=$(printf "%X" $RANDOM$(date +%M%S)$$)
     uuid=${uuid%%-*}
     [ $# -eq 0 ] && echo ${uuid}-${ERLANG_NODE}
@@ -431,16 +428,16 @@ wait_for_status()
 }
 
 # main handler
-case "${ARGS[0]}" in
+case $@ in
     'start') start;;
     'debug') debug;;
     'iexdebug') iexdebug;;
     'live') live;;
     'iexlive') iexlive;;
     'foreground') foreground;;
-    'ping'*) ping ${ARGS[1]};;
+    'ping'*) shift; ping "$@";;
     'etop') etop;;
     'started') wait_for_status 0 30 2;; # wait 30x2s before timeout
     'stopped') wait_for_status 3 30 2 && stop_epmd;; # wait 30x2s before timeout
-    *) ctl "${ARGS[@]}";;
+    *) ctl "$@";;
 esac