Update grubeditor.sh to 0.2.0

Multiple delicious improvements:
- Better algorithm for creating new copies of romfiles
- Updated, improved nomenclature for various variables and routines
- Removed brackets in "${quoted}" variables as much as possible to improve execution time
- Whatever else the diff reveals!

1 files changed, 243 insertions, 146 deletions

diff --git a/resources/scripts/misc/grubeditor.sh b/resources/scripts/misc/grubeditor.sh
index f6ccb728..84284645 100644
--- a/resources/scripts/misc/grubeditor.sh
+++ b/resources/scripts/misc/grubeditor.sh
@@ -19,34 +19,6 @@
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 
-# Usage:
-# ./grubeditor.sh [options] romimage
-#
-# Supported options:
-#
-# -h | --help: show usage help
-#
-# -r | --realcfg: generate grub.cfg instead of grubtest.cfg
-#
-# -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 $EDITOR
-#
-# -s | --swapcfg: swap grub.cfg and grubtest.cfg, incompatible with other
-# options besides -i
-#
-# -x | --extractcfg: extract either grub.cfg or grubtest.cfg depending on
-# whether -r is set
-#
-# -d | --diffcfg: diff grub.cfg and grubtest.cfg, incompatible with other
-# options besides -D
-#
-# -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
@@ -54,18 +26,57 @@
 # -e kills the script if any function returns not-zero
 #set -u
 
+##############
+# HELP COMMAND
+##############
+
+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.
+
+Usage:
+
+$0 [OPTIONS] [ROMFILE]
+
+Options:
+
+-h | --help: show usage help
+
+-r | --realcfg: generate grub.cfg instead of grubtest.cfg
+
+-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
+
+-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
+
+-x | --extract: extract either grub.cfg or grubtest.cfg
+depending on -r option
+HELPSCREEN
+}
+
 # Version number of script
-geversion="0.1.1"
+geversion="0.2.0"
 
 # Define the list of available option in both short and long form.
-shortopts="hrie:sdD:"
-longopts="help,realcfg,inplace,editor:,swapcfgs,diffcfgs,differ:"
+shortopts="hvrie:sdD:x"
+longopts="help,version,realcfg,inplace,editor:,swapcfgs,diffcfgs,differ:,extract"
 
 # Variables for modifying the program's operation
 edit_realcfg=0
 edit_inplace=0
 do_swapcfgs=0
 do_diffcfgs=0
+do_extract=0
 # Path to cbfstool, filled by detect_architecture
 # (Possible to provide explicitly and disclaim warranty?)
 cbfstool=""
@@ -80,7 +91,18 @@ differ_rawarg=""
 # Last but not least, the rom file itself
 romfile=""
 
-# This program works primarily from a cascade of functions. Let's define them.
+############################
+#### PRIMARY FUNCTIONS #####
+############################
+# The script effectively lives in a series of function definitions, which are
+# provided here before their calls to ensure that they have been declared.
+#
+# Please scroll to the bottom of the script to see how this cascade of
+# functions gets initiated.
+
+################
+# OPTION SCRAPER
+################
 
 get_options() {
     # Test for enhanced getopt.
@@ -91,7 +113,7 @@ get_options() {
     fi
 
     # Parse the command line options based on the previously defined values. 
-    parsedopts=$(getopt --options ${shortopts} --longoptions ${longopts} --name "${0}" -- "$@")
+    parsedopts=$(getopt --options $shortopts --longoptions $longopts --name "$0" -- "$@")
     if [[ $? -ne 0 ]]; then # getopt didn't approve of your arguments
         echo "Unrecognized options."
         exit 206
@@ -137,6 +159,10 @@ get_options() {
                 differ_rawarg="$2" 
                 shift 2
                 ;;
+            -x|--extract)
+                do_extract=1
+                shift
+                ;;
             --)
                 # Stop interpreting arguments magically.
                 shift
@@ -144,7 +170,7 @@ get_options() {
                 ;;
             *)
                 echo "Something went wrong while interpreting the arguments!"
-                echo "I hit \"${1}\" and don't know what to do with it."
+                echo "I hit \"$1\" and don't know what to do with it."
                 exit 209
                 ;;
         esac
@@ -167,13 +193,13 @@ determine_architecture() {
     # is over, the variable $cbfstool gets filled with the appropriate value
     # for use by the rest of the script.
     arch="$(uname -m)"
-    case "${arch}" in
+    case "$arch" in
         armv7l|i686|x86_64)
-            echo "Supported architecture \"${arch}\" detected. You may proceed."
-            cbfstool="${0%/*}/cbfstool/${arch}/cbfstool"
+            echo "Supported architecture \"$arch\" detected. You may proceed."
+            cbfstool="${0%/*}/cbfstool/$arch/cbfstool"
             ;;
         *) 
-            echo "Unsupported architecture \"${arch}\" detected! You may not proceed."
+            echo "Unsupported architecture \"$arch\" detected! You may not proceed."
             exit 230
             ;;
     esac
@@ -186,85 +212,98 @@ determine_operation() {
     elif [[ $do_diffcfgs -eq 1 ]]; then
         diff_configs
         exit $?
+    elif [[ $do_extract -eq 1 ]]; then
+        extract_config
+        exit $?
     else
         edit_config
         exit $?
     fi
 }
 
-# These functions are not part of the primary function cascade but are
-# referenced within them either directly or indirectly from other helper
-# functions depending on the operations requested by the user.
+################
+# VERSION SHOWER
+################
+
+show_version() {
+    echo "$0 $geversion"
+}
+
+##########################
+# EXTERNAL COMMAND FINDERS
+##########################
 
-# External command finders.
 find_differ() {
     found_differ=0
 
-    if [[ -n "${differ_rawarg}" ]]; then
-        which "${differ_rawarg}" &> /dev/null
+    if [[ -n "$differ_rawarg" ]]; then
+        which "$differ_rawarg" &> /dev/null
         if [[ $? -eq 0 ]]; then
-            echo "Using differ \"${differ_rawarg}\"..."
-            use_differ="${differ_rawarg}"
+            echo "Using differ \"$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}"
+            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}"
+        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 [[ -n "$editor_rawarg" ]]; then
+        which "$editor_rawarg" &> /dev/null
         if [[ $? -eq 0 ]]; then
-            echo "Using editor \"${editor_rawarg}\"..."
-            use_editor="${editor_rawarg}"
+            echo "Using editor \"$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}"
+            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 "${EDITOR}" &> /dev/null
+        if [[ -n "$EDITOR" ]]; then
+            which "$EDITOR" &> /dev/null
             if [[ $? -ne 0 ]]; then
-                echo "Your \$EDITOR is defined as ${EDITOR}, but is not a valid command!"
+                echo "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}"
+                echo "Defaulting to $default_editor..."
+                use_editor="$default_editor"
             else
                 echo "Using your defined \$EDITOR \"$EDITOR\"..."
-                use_editor="${EDITOR}"
+                use_editor="$EDITOR"
             fi
         else
-            echo "\$EDITOR blank, defaulting to ${default_editor}..."
-            use_editor="${default_editor}"
+            echo "\$EDITOR blank, defaulting to $default_editor..."
+            use_editor="$default_editor"
         fi
     fi
 }
 
-# Filename randomizer.
-random_filer() {
+#######################
+# FILE NAMING FUNCTIONS
+#######################
+
+random_tempcfg() {
     # 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"
+    [[ -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.)
@@ -272,60 +311,76 @@ random_filer() {
 
     # 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 $size | head -n 1)
+        rand="$(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}_${rand}.tmp.cfg"
+        possible="$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}" 
+        if [[ ! -f "$possible" ]]; then
+            echo "$possible" 
             break
         fi
-
     done
 }
 
-# Primary command functions.
-show_help() {
-    cat << HELPSCREEN
-"${0}" -- conveniently edit grub{test}.cfg files in Libreboot ROM image files by automating their extraction with cbfstool and the user's editor of choice.
-
-Usage:
-
-"${0}" [OPTIONS] [ROMFILE]
-
-Options:
-
--h | --help: show usage help
-
--r | --realcfg: generate grub.cfg instead of grubtest.cfg
-
--i | --inplace: do not create a .modified romfile, instead modify the
-existing file
+modified_romfile() {
+    # Inputs:
+    # $1 is the path to the file, optional
+    # $2 provides an optional description of the modification
+    [[ -n "$1" ]] && fullname="$1" || fullname=""
+    [[ -n "$2" ]] && operation="$2" || operation="altered"
+
+    # Attempt to extract an extension from the file (it's probably .rom but
+    # can't assume so). $extension will not include prefixing dot, just the
+    # extension itself!
+    if [[ "$fullname" = *.* ]]; then
+        extension="${fullname##*.}"
+    else
+        extension=""
+    fi
 
--e | --editor [/path/to/]editor: open the cfg file with /path/to/editor instead of the value of \$EDITOR
+    # Break up full path into containing directory and raw filename, providing
+    # an attempt at graceful failure if they are absent.
+    if [[ -z "$fullname" ]]; then
+        dirname="/tmp"
+        filename="grubedited"
+    else
+        dirname="$(dirname "$fullname")"
+        if [[ -z "$extension" ]]; then
+            filename="$(basename "$fullname")"
+        else
+            filename="$(basename "$fullname" ".$extension")"
+        fi
+    fi
 
--s | --swapcfg: swap grub.cfg and grubtest.cfg
+    # Loop forever until a free filename is found.
+    while [[ 1 ]]; do
+        # Grab the current date.
+        now="$(date +"%Y%m%d_%H%M%S")"
 
--d | --diffcfg: diff grub.cfg and grubtest.cfg
+        # Build a complete filename with a hardcoded extension.
+        possible="$dirname/${filename}-${now}-${operation}.${extension}"
 
--D | --differ [/path/to/]differ: use /path/to/differ instead of "diff", can be an interactive program like vimdiff
-HELPSCREEN
+        # See if file doesn't exist and return it as string or keep going.
+        if [[ ! -f "$possible" ]]; then
+            echo "$possible" 
+            break
+        fi
+    done
 }
 
-show_version() {
-    echo "${geversion}"
-}
+###########################
+# PRIMARY PROGRAM FUNCTIONS
+###########################
 
 swap_configs() {
     # Procedure:
     # 1. Call cbfstool twice, once each to extract grub.cfg and grubtest.cfg.
-    # 2. If --inplace not specified, copy ${romfile} to ${romfile}.modified and
-    # implement remaining steps on this copy. Otherwise, implement remaining
-    # steps on ${romfile}.
+    # 2. If --inplace not specified, copy $romfile to a new file and implement
+    # remaining steps on this copy. Otherwise, implement remaining steps on
+    # $romfile.
     # 3. Call cbfstool twice, once each to delete grub.cfg and grubtest.cfg
     # from romfile.
     # 4. Call cbfstool twice, once to embed grubtest.cfg as grub.cfg into
@@ -334,74 +389,83 @@ swap_configs() {
     # 6. You're done!
 
     # Extract config files from provided romfile.
-    real2test="$(random_filer "real2test")"
-    test2real="$(random_filer "test2real")"
-    "${cbfstool}" "${romfile}" extract -n grub.cfg -f "${real2test}"
-    "${cbfstool}" "${romfile}" extract -n grubtest.cfg -f "${test2real}"
+    real2test="$(random_tempcfg "real2test")"
+    test2real="$(random_tempcfg "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 [[ $edit_inplace -eq 1 ]]; then
-        outfile="${romfile}"
+        outfile="$romfile"
     else
-        cp "${romfile}" "${romfile}.modified"
-        outfile="${romfile}.modified"
+        outfile="$(modified_romfile "$romfile" "swapped")"
+        cp "$romfile" "$outfile"
+        echo "Saving modified romfile to $outfile"
     fi
 
+    # Since we are swapping the configs, we must modify their "load test config"
+    # options or else they will simply reference themselves, rendering the user
+    # unable to (easily) load the other config.
+    sed -i -e 's/Load test configuration (grubtest.cfg)/Load test configuration (grub.cfg)/' "$real2test" 
+    sed -i -e 's/configfile \/grubtest.cfg/configfile \/grub.cfg/' "$real2test" 
+    sed -i -e 's/Load test configuration (grub.cfg)/Load test configuration (grubtest.cfg)/' "$test2real" 
+    sed -i -e 's/configfile \/grub.cfg/configfile \/grubtest.cfg/' "$test2real" 
+
     # 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}" ${outfile} add -t raw -n grub.cfg -f "${test2real}"
-    "${cbfstool}" ${outfile} add -t raw -n grubtest.cfg -f "${real2test}"
+    "$cbfstool" "$outfile" add -t raw -n grub.cfg -f "$test2real"
+    "$cbfstool" "$outfile" add -t raw -n grubtest.cfg -f "$real2test"
     
     # Delete the tempfiles.
-    rm "${test2real}" "${real2test}"
+    rm "$test2real" "$real2test"
 }
 
 diff_configs() {
     # Procedure:
     # 1. Call cbfstool twice, once to extract grub.cfg and grubtest.cfg.
-    # 2. Execute ${use_differ} grub.cfg grubtest.cfg #.
+    # 2. Execute $use_differ grub.cfg grubtest.cfg #.
     # 3. Delete the extracted grub.cfg and grubtest.cfg files.
     # 4. You're done!
 
     # Determine the differ command to use.
     find_differ
 
-    grubcfg="$(random_filer "grubcfg")"
-    testcfg="$(random_filer "testcfg")"
+    grubcfg="$(random_tempcfg "grubcfg")"
+    grubtestcfg="$(random_tempcfg "grubtestcfg")"
 
     # Extract config files from provided romfile.
-    "${cbfstool}" "${romfile}" extract -n grub.cfg -f "${grubcfg}"
-    "${cbfstool}" "${romfile}" extract -n grubtest.cfg -f "${testcfg}"
+    "$cbfstool" "$romfile" extract -n grub.cfg -f "$grubcfg"
+    "$cbfstool" "$romfile" extract -n grubtest.cfg -f "$grubtestcfg"
 
     # Run the differ command with real as first option, test as second option.
-    "${use_differ}" "${grubcfg}" "${testcfg}"
+    "$use_differ" "$grubcfg" "$grubtestcfg"
 
     # Delete the temporary copies of the configuration files.
-    rm "${grubcfg}"
-    rm "${testcfg}"
+    rm "$grubcfg"
+    rm "$grubtestcfg"
 }
 
 edit_config() {
     # Procedure:
-    # 1. If --realcfg specified, set ${thisconfig} to "grub.cfg". Otherwise,
-    # set ${thisconfig} to "grubtest.cfg".
-    # 2. Call cbfstool once to extract ${thisconfig} from ${romfile}.
-    # 3. Run ${use_editor} ${thisconfig}.
-    # 4. If ${use_editor} returns zero, proceed with update procedure:
-    # 5. Call cbfstool once to extract ${thisconfig} from ${romfile}.
+    # 1. If --realcfg specified, set $thisconfig to "grub.cfg". Otherwise,
+    # set $thisconfig to "grubtest.cfg".
+    # 2. Call cbfstool once to extract $thisconfig from $romfile.
+    # 3. Run $use_editor $thisconfig.
+    # 4. If $use_editor returns zero, proceed with update procedure:
+    # 5. Call cbfstool once to extract $thisconfig from $romfile.
     # 6. Quietly diff the extracted file with the edited file. If diff returns
     # zero, take no action: warn the user that the files were the same, delete
     # both files, then skip the remaining steps (you're done)! Otherwise, the
     # files are different and you must continue with the update procedure.
-    # 7. If --inplace not specified, copy ${romfile} to ${romfile}.modified and
+    # 7. If --inplace not specified, copy $romfile to a new filename and
     # implement remaining steps on this copy. Otherwise, implement remaining
-    # steps on ${romfile}.
-    # 8. Call cbfstool once to delete internal pre-update ${thisconfig} from
+    # steps on $romfile.
+    # 8. Call cbfstool once to delete internal pre-update $thisconfig from
     # the rom file.
-    # 9. Call cbfstool once to embed the updated ${thisconfig} that was just
+    # 9. Call cbfstool once to embed the updated $thisconfig that was just
     # edited into the rom file.
     # 10. Alert the user of success (either explicitly or by not saying
     # anything, either way return zero).
@@ -418,42 +482,75 @@ edit_config() {
     fi
 
     # Extract the desired configuration file from the romfile.
-    tmp_editme="$(random_filer "${thisconfig%.cfg}")"
-    "${cbfstool}" "${romfile}" extract -n "${thisconfig}" -f "${tmp_editme}"
+    tmp_editme="$(random_tempcfg "${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.
             # (This code should really be genericized and placed in a function
             # to avoid repetition.)
             if [[ $edit_inplace -eq 1 ]]; then
-                outfile="${romfile}"
+                outfile="$romfile"
             else
-                cp "${romfile}" "${romfile}.modified"
-                outfile="${romfile}.modified"
+                if [[ $edit_realcfg -eq 1 ]]; then
+                    op="realcfg"
+                else
+                    op="testcfg"
+                fi
+                outfile="$(modified_romfile "$romfile" "${op}_edited")"
+                cp "$romfile" "$outfile"
+                echo "Saving modified romfile to $outfile"
             fi
             # Remove the old config, add in the new one.
-            "${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 "${tmp_refcfg}"
+        rm "$tmp_editme"
+        rm "$tmp_refcfg"
+    fi
+}
+
+extract_config() {
+    # This simply extracts a given config and responds to
+    # the -r flag.
+
+    # Determine whether we are extracting the real config or the test config.
+    if [[ $edit_realcfg -eq 1 ]]; then
+        thisconfig="grub.cfg"
+    else
+        thisconfig="grubtest.cfg"
+    fi
+
+    # Extract to a unique filename.
+    tmp_extractme="$(random_tempcfg "${thisconfig%.cfg}" "$(dirname "$romfile")")"
+    "$cbfstool" "$romfile" extract -n "$thisconfig" -f "$tmp_extractme"
+    err=$?
+
+    # Determine if cbfstool reported success.
+    if [[ $err -ne 0 ]]; then
+        echo "cbfstool reported an error ($err). If it succeeded anyway, check $tmp_extractme."
+    else
+        echo "Extracted $thisconfig from $romfile to file $tmp_extractme."
     fi
 }
 
+#################################
+#### PRIMARY EXECUTION FLOW #####
+#################################
 # Run through the primary function cascade.
 get_options $@
 determine_architecture