grubeditor.sh

Updates to script:
- Fixed broken test/actual config swapper
- Updated cbfstool variable to reflect the script's home, not the romfile's home
- Updated help screen to use long lines and provide actual usage syntax
- Added a version number and included a function that displays it

1 files changed, 131 insertions, 87 deletions

diff --git a/resources/scripts/misc/grubeditor.sh b/resources/scripts/misc/grubeditor.sh
index 025161f3..832e0dc6 100644
--- a/resources/scripts/misc/grubeditor.sh
+++ b/resources/scripts/misc/grubeditor.sh
@@ -46,6 +46,13 @@
 # -D | --differ [/path/to/]differ: use /path/to/differ instead of "diff", can
 # be an interactive program like vimdiff
 
+# THIS BLOCK IS EXPERIMENTAL
+# Allow debugging by running DEBUG= ${0}.
+[[ "x${DEBUG+set}" = 'xset' ]] && set -v
+# -u kills the script if any variables are unassigned
+# -e kills the script if any function returns not-zero
+#set -u
+
 # Define the list of available option in both short and long form.
 shortopts="hrie:sdD:"
 longopts="help,realcfg,inplace,editor:,swapcfgs,diffcfgs,differ:"
@@ -154,7 +161,7 @@ determine_architecture() {
     case "${arch}" in
         armv7l|i686|x86_64)
             echo "Supported architecture \"${arch}\" detected. You may proceed."
-            cbfstool="./cbfstool/${arch}/cbfstool"
+            cbfstool="${0%/*}/cbfstool/${arch}/cbfstool"
             ;;
         *) 
             echo "Unsupported architecture \"${arch}\" detected! You may not proceed."
@@ -180,10 +187,108 @@ determine_operation() {
 # referenced within them either directly or indirectly from other helper
 # functions depending on the operations requested by the user.
 
+# External command finders.
+find_differ() {
+    found_differ=0
+
+    if [[ -n "${differ_rawarg}" ]]; then
+        which "${differ_rawarg}" &> /dev/null
+        if [[ $? -eq 0 ]]; then
+            echo "Using differ \"${differ_rawarg}\"..."
+            use_differ="${differ_rawarg}"
+            found_differ=1
+        else
+            echo "The provided \"${differ_rawarg}\" is not a valid command!"
+            echo "Defaulting to ${default_differ}..."
+            use_differ="${default_differ}"
+        fi
+    fi
+    
+    if [[ $found_differ -eq 1 ]]; then 
+        return
+    else
+        echo "Defaulting to ${default_differ}..."
+        use_differ="${default_differ}"
+    fi
+}
+
+find_editor() {
+    found_editor=0
+
+    if [[ -n "${editor_rawarg}" ]]; then
+        which "${editor_rawarg}" &> /dev/null
+        if [[ $? -eq 0 ]]; then
+            echo "Using editor \"${editor_rawarg}\"..."
+            use_editor="${editor_rawarg}"
+            found_editor=1
+        else
+            echo "The provided \"${editor_rawarg}\" is not a valid command!"
+            echo "Defaulting to ${default_editor}..."
+            use_editor="${default_editor}"
+        fi
+    fi
+    
+    if [[ $found_editor -eq 1 ]]; then 
+        return
+    else
+        if [[ -n "${EDITOR}" ]]; then
+            which "${EDITOR}" &> /dev/null
+            if [[ $? -ne 0 ]]; then
+                echo "Your \$EDITOR is defined as ${EDITOR}, but is not a valid command!"
+                echo "(This is bad. I highly suggest fixing this in your ~/.bashrc.)"
+                echo "Defaulting to ${default_editor}..."
+                use_editor="${default_editor}"
+            else
+                echo "Using your defined \$EDITOR \"$EDITOR\"..."
+                use_editor="${EDITOR}"
+            fi
+        else
+            echo "\$EDITOR blank, defaulting to ${default_editor}..."
+            use_editor="${default_editor}"
+        fi
+    fi
+}
+
+# Filename randomizer.
+random_filer() {
+    # Inputs:
+    # $1 is a descriptive label for the file
+    # $2 is directory (becomes /tmp if not set)
+    [[ -n "${1}" ]] && label="${1}" || label="tempfile"
+    [[ -n "${2}" ]] && savedir="${2%/}" || savedir="/tmp"
+
+    # Hardcoded string size for multiple good reasons (no processing weird
+    # input, prevent malicious overflows, etc.)
+    size=5
+
+    # Loop forever until a free filename is found.
+    while [[ 1 ]]; do
+
+        # Read data from /dev/urandom and convert into random ASCII strings.
+        rand=$(cat /dev/urandom | tr -dc 'a-zA-Z' | fold -w $size | head -n 1)
+
+        # Build a complete filename with a hardcoded extension.
+        possible="${savedir}/${label}_${rand}.tmp.cfg"
+
+        # See if file doesn't exist and return it as string or keep going.
+        if [[ ! -f "${possible}" ]]; then
+            echo "${possible}" 
+            break
+        fi
+
+    done
+}
+
+# Primary command functions.
 show_help() {
     cat << HELPSCREEN
-${0} -- conveniently edit grub{test}.cfg files in Libreboot ROM image files by
-automating their extraction with cbfstool and the user's editor of choice.
+"${0}" -- conveniently edit grub{test}.cfg files in Libreboot ROM image files by automating their extraction with cbfstool and the user's editor of choice.
+
+Usage:
+
+"${0}" [OPTIONS] [ROMFILE]
+
+Options:
 
 -h | --help: show usage help
 
@@ -192,15 +297,13 @@ automating their extraction with cbfstool and the user's editor of choice.
 -i | --inplace: do not create a .modified romfile, instead modify the
 existing file
 
--e | --editor [/path/to/]editor: open the cfg file with /path/to/editor instead
-of the value of \$EDITOR
+-e | --editor [/path/to/]editor: open the cfg file with /path/to/editor instead of the value of \$EDITOR
 
 -s | --swapcfg: swap grub.cfg and grubtest.cfg
 
 -d | --diffcfg: diff grub.cfg and grubtest.cfg
 
--D | --differ [/path/to/]differ: use /path/to/differ instead of "diff", can be
-an interactive program like vimdiff
+-D | --differ [/path/to/]differ: use /path/to/differ instead of "diff", can be an interactive program like vimdiff
 HELPSCREEN
 }
 
@@ -218,8 +321,10 @@ swap_configs() {
     # 6. You're done!
 
     # Extract config files from provided romfile.
-    ${cbfstool} ${romfile} extract -n grub.cfg -f /tmp/real2test.cfg
-    ${cbfstool} ${romfile} extract -n grubtest.cfg -f /tmp/test2real.cfg
+    real2test="$(random_filer "real2test")"
+    test2real="$(random_filer "test2real")"
+    "${cbfstool}" "${romfile}" extract -n grub.cfg -f "${real2test}"
+    "${cbfstool}" "${romfile}" extract -n grubtest.cfg -f "${test2real}"
 
     # Determine whether to edit inplace or make a copy.
     if [[ $edit_inplace -eq 1 ]]; then
@@ -230,15 +335,15 @@ swap_configs() {
     fi
 
     # Remove config files from the output file.
-    ${cbfstool} ${outfile} remove -n grub.cfg
-    ${cbfstool} ${outfile} remove -n grubtest.cfg
+    "${cbfstool}" "${outfile}" remove -n grub.cfg
+    "${cbfstool}" "${outfile}" remove -n grubtest.cfg
 
     # Embed new configs into the output file.
-    ${cbfstool} ${outfile} add -t raw -n grub.cfg -f /tmp/test2real.cfg
-    ${cbfstool} ${outfile} add -t raw -n grubtest.cfg -f /tmp/real2test.cfg
+    "${cbfstool}" ${outfile} add -t raw -n grub.cfg -f "${test2real}"
+    "${cbfstool}" ${outfile} add -t raw -n grubtest.cfg -f "${real2test}"
     
     # Delete the tempfiles.
-    rm /tmp/test2real.cfg /tmp/real2test.cfg
+    rm "${test2real}" "${real2test}"
 }
 
 diff_configs() {
@@ -252,11 +357,11 @@ diff_configs() {
     find_differ
 
     # Extract config files from provided romfile.
-    ${cbfstool} ${romfile} extract -n grub.cfg -f /tmp/grub_tmpdiff.cfg
-    ${cbfstool} ${romfile} extract -n grubtest.cfg -f /tmp/grubtest_tmpdiff.cfg
+    "${cbfstool}" "${romfile}" extract -n grub.cfg -f /tmp/grub_tmpdiff.cfg
+    "${cbfstool}" "${romfile}" extract -n grubtest.cfg -f /tmp/grubtest_tmpdiff.cfg
 
     # Run the differ command with real as first option, test as second option.
-    ${use_differ} /tmp/grub_tmpdiff.cfg /tmp/grubtest_tmpdiff.cfg
+    "${use_differ}" /tmp/grub_tmpdiff.cfg /tmp/grubtest_tmpdiff.cfg
 }
 
 edit_config() {
@@ -293,19 +398,19 @@ edit_config() {
     fi
 
     # Extract the desired configuration file from the romfile.
-    tmp_editme="/tmp/${thisconfig%.cfg}_editme.cfg"
-    ${cbfstool} ${romfile} extract -n ${thisconfig} -f ${tmp_editme}
+    tmp_editme="$(random_filer "${thisconfig%.cfg}")"
+    "${cbfstool}" "${romfile}" extract -n "${thisconfig}" -f "${tmp_editme}"
 
     # Launch the editor!
-    ${use_editor} ${tmp_editme}
+    "${use_editor}" "${tmp_editme}"
 
     # Did the user commit the edit?
     if [[ $? -eq 0 ]]; then
         # See if it actually changed from what exists in the cbfs.
         tmp_refcfg="/tmp/${thisconfig%.cfg}_ref.cfg"
-        ${cbfstool} ${romfile} extract -n ${thisconfig} -f ${tmp_refcfg}
+        "${cbfstool}" "${romfile}" extract -n "${thisconfig}" -f "${tmp_refcfg}"
         # Diff the files as quietly as possible.
-        diff -q ${tmp_editme} ${tmp_refcfg} &> /dev/null
+        diff -q "${tmp_editme}" "${tmp_refcfg}" &> /dev/null
         if [[ $? -ne 0 ]]; then
             # The files differ, so it won't be frivolous to update the config.
             # See if the user wants to edit the file in place.
@@ -318,75 +423,14 @@ edit_config() {
                 outfile="${romfile}.modified"
             fi
             # Remove the old config, add in the new one.
-            ${cbfstool} ${outfile} remove -n ${thisconfig}
-            ${cbfstool} ${outfile} add -t raw -n ${thisconfig} -f ${tmp_editme}
+            "${cbfstool}" "${outfile}" remove -n "${thisconfig}"
+            "${cbfstool}" "${outfile}" add -t raw -n "${thisconfig}" -f "${tmp_editme}"
         else
             echo "No changes to config file. Not updating the ROM image."
         fi
         # We are done with the config files. Delete them.
-        rm ${tmp_editme}
-        rm ${tmp_refcfg}
-    fi
-}
-
-find_differ() {
-    found_differ=0
-
-    if [[ -n "${differ_rawarg}" ]]; then
-        which "${differ_rawarg}" &> /dev/null
-        if [[ $? -eq 0 ]]; then
-            echo "Using differ \"${differ_rawarg}\"..."
-            use_differ="${differ_rawarg}"
-            found_differ=1
-        else
-            echo "The provided \"${differ_rawarg}\" is not a valid command!"
-            echo "Defaulting to ${default_differ}..."
-            use_differ="${default_differ}"
-        fi
-    fi
-    
-    if [[ $found_differ -eq 1 ]]; then 
-        return
-    else
-        echo "Defaulting to ${default_differ}..."
-        use_differ="${default_differ}"
-    fi
-}
-
-find_editor() {
-    found_editor=0
-
-    if [[ -n "${editor_rawarg}" ]]; then
-        which "${editor_rawarg}" &> /dev/null
-        if [[ $? -eq 0 ]]; then
-            echo "Using editor \"${editor_rawarg}\"..."
-            use_editor="${editor_rawarg}"
-            found_editor=1
-        else
-            echo "The provided \"${editor_rawarg}\" is not a valid command!"
-            echo "Defaulting to ${default_editor}..."
-            use_editor="${default_editor}"
-        fi
-    fi
-    
-    if [[ $found_editor -eq 1 ]]; then 
-        return
-    else
-        if [[ -n "${EDITOR}" ]]; then
-            which "${EDITOR}" &> /dev/null
-            if [[ $? -ne 0 ]]; then
-                echo "Your \$EDITOR is defined as ${EDITOR}, but is not a valid command!"
-                echo "(This is bad. I highly suggest fixing this in your ~/.bashrc.)"
-                echo "Defaulting to ${default_editor}..."
-                use_editor="${default_editor}"
-            else
-                echo "Using your defined \$EDITOR \"$EDITOR\"..."
-                use_editor="${EDITOR}"
-            fi
-        else
-            echo "\$EDITOR blank, defaulting to ${default_editor}..."
-            use_editor="${default_editor}"
-        fi
+        rm "${tmp_editme}"
+        rm "${tmp_refcfg}"
     fi
 }