mkinitcpio: refactor and bashify early path calculations

This addresses a few issues with creation of images with a $BASEDIR, the
most alarming that images would always be created on the real root
filesystem, with no regard for any supplied base directory. This also
cleans up some repetitive path declaration wrt BASEDIR and MODULEDIR.

Signed-off-by: Dave Reisner <d@falconindy.com>

1 files changed, 27 insertions, 26 deletions

diff --git a/mkinitcpio b/mkinitcpio
index 95c7923..70c5d5e 100755
--- a/mkinitcpio
+++ b/mkinitcpio
@@ -172,7 +172,7 @@ if [[ $PRESET ]]; then
 
             preset_image=${p}_image
             if [[ ${!preset_image} ]]; then
-                preset_cmd+=(-g "${!preset_image}")
+                preset_cmd+=(-g "$BASEDIR${!preset_image}")
             else
                 echo "==> No image file specified. Skipping image \"${p}\"."
                 continue
@@ -199,41 +199,42 @@ if [[ $PRESET ]]; then
     fi
 fi
 
-# remove trailing / from BASEDIR
-BASEDIR="${BASEDIR%/}"
-
-MODULEDIR="${BASEDIR}/lib/modules/${KERNELVERSION}"
-
-if [[ $GENIMG ]]; then
-  IMGPATH=$(readlink -f "$GENIMG")
-  if [[ -z $IMGPATH || ! -w ${IMGPATH%/*} ]]; then
-    echo "error: unable to write to path: '$GENIMG'"
-    cleanup
-    exit 1
-  fi
-fi
-
-if [ -n "${BASEDIR}" ]; then
-    if [ "${BASEDIR}" = "${BASEDIR#/}" ]; then
-        BASEDIR="$(pwd)/${BASEDIR}"
-    elif [ ! -d "${BASEDIR}" ]; then
-        echo "base directory '${BASEDIR}' does not exist or is not a directory"
+if [[ $BASEDIR ]]; then
+    # resolve the path. it might be a relative path and/or contain symlinks
+    abspath=$(readlink -e "$BASEDIR")
+    if [[ -z $abspath ]]; then
+        echo "base directory '$BASEDIR' does not exist or is not a directory"
         cleanup
         exit 1
     fi
+    BASEDIR=$abspath
+    unset abspath
 fi
 
-if [ ! -f "${CONFIG}" ]; then
-    echo "config file '${CONFIG}' cannot be found, aborting..."
+if [[ $GENIMG ]]; then
+    IMGPATH=$(readlink -f "$GENIMG")
+    if [[ -z $IMGPATH || ! -w ${IMGPATH%/*} ]]; then
+      echo "error: unable to write to path: '$GENIMG'"
+      cleanup
+      exit 1
+    fi
+fi
+
+if [[ ! -f "$CONFIG" ]]; then
+    echo "config file '$CONFIG' cannot be found, aborting..."
     cleanup
     exit 1
 fi
-. "${CONFIG}"
+. "$CONFIG"
 
-BASEDIR=${BASEDIR//+(\/)//}
-MODULEDIR=${MODULEDIR//+(\/)//}
+MODULEDIR=$BASEDIR/lib/modules/$KERNELVERSION
+if [[ ! -d $MODULEDIR ]]; then
+    echo "error: '$MODULEDIR' is not a valid kernel module directory"
+    cleanup
+    exit 1
+fi
 
-. "${FUNCTIONS}"
+. "$FUNCTIONS"
 
 if [ "${SHOW_AUTOMODS}" = "y" ]; then
     echo "Modules autodetected:"