#!/bin/sh

# Merge all the .xml rulesets into a single "default.rulesets" file -- this

# prevents inodes from wasting disk space, but more importantly, works around

# the fact that zip does not perform well on a pile of small files.

RULESETS=chrome/content/rules/default.rulesets

INDENT_CHAR=' '

# Any whitespace that marks one level of indentation.

TAG_DEFINITIONS='

# tag | level of indentation | + prepended linebreaks | + appended linebreaks

rulesetlibrary 0 -1 0

ruleset 0 1 0

rule 1 0 0

target 1 0 0

exclusion 2 0 0

securecookie 2 0 0'

# Extra prepended linebreaks are added before the opening <tags>,

# and appended after closing </tags> and <tags/>. It's not perfect but it works.

# One linebreak is implicitly prepended; opt out by supplying -1

# This does not work whatsoever with nested tags, mind.

SED_TRIM_CMD='

:a

s/<!--.*-->//g

/<!--/N

//ba

s/\([^ ]\)\(to\|from\|name\)=/\1 \2=/g

s: />:/>:g

s/\([^ ]\) \{2,\}/\1/g

s/ \+$//g

s:\(http[s?]\{,2\}\)[^:]//:\1\://:g

s:\([^:]\)/\{2,\}:\1/:g'

# sed command to scrub comments and fix various whitespace irregularities;

# missing whitespace inbetween tag fields: <x y="z"trapped=":("/>,

# random double and trailing whitespace, unwanted whitespace before '/>',

# semicolons after protocols;// (rather than colons), and mid-URI double slashes

# Functions

repeat_char() {

[ $2 -gt 0 ] || return

local i

for i in $(seq 1 $2); do printf "$1"; done

}

format_rulesets() {

local IFS tag idepth prebreaks postbreaks

local _indent _pre _post _sed_pre _sed_post _sed_oneshot

# Print pretty banner, very hardcoded

printf '\n'

printf '%15s | %s | %s | %s\n' 'tag name' 'indent' 'prebreak' 'postbreak'

printf '%15s-+-%s-+-%s-+-%s\n' \

'-------------' '------' '--------' '----------'

# Iterate through tags and add appropriate indentation and linebreaks

while read tag idepth prebreaks postbreaks; do

( [ "$tag" = '#' ] || [ ! $postbreaks ] ) && continue # Invalid; skip

unset _indent _pre _post _sed_pre _sed_post _sed_oneshot

printf "%15s | %6d | %8d | %9s\n" "$tag" $idepth $prebreaks $postbreaks

# Special characters (\n) need double escaping when saved to a variable

# since they are dereferenced and break everytime they're passed around.

# bash printf has a %q format character for this, but we're /bin/sh

# Should always be a prepended linebreak unless we opt out with -1

_pre="$(repeat_char '\\n' $((prebreaks+1)))"

_post="$(repeat_char '\\n' $postbreaks)"

_indent="$(repeat_char "$INDENT_CHAR" $idepth)"

# breaks before opening <tags> and <tags/>

_sed_pre="s:<${tag}[ />]:${_pre}${_indent}\0:g;"

# breaks after closing </tags>

_sed_post="s:</${tag}>:\n${_indent}\0${_post}:g;"

# breaks after oneshot <tags/>

_sed_oneshot="s:<${tag}\(/>\| [^>]\+/>\):\0${_post}:g;"

sed -ir "$_sed_pre $_sed_post $_sed_oneshot" $RULESETS

done <<- EOF

$TAG_DEFINITIONS

EOF

echo #padding for some distance after the tag table

}

rulesize() {

wc -c < $RULESETS

}

populate_rulesets() {

local xmlfile

# Under git bash, sed -i issues errors and sets the file "read only"

[ -f "$RULESETS" ] && chmod u+w $RULESETS

printf '<rulesetlibrary gitcommitid="%s">' \

"${GIT_COMMIT_ID:-unset}" > $RULESETS

# Include the filename.xml as the "f" attribute

for xmlfile in chrome/content/rules/*.xml; do

sed "s/<ruleset/\0 f=\"${xmlfile##*/}\"/g" "$xmlfile" >> $RULESETS

done

echo "</rulesetlibrary>" >> $RULESETS

}

flatten_file() {

# Strip *all* control chars; we'll re-add them soon as per tag definitions.

# tr cannot edit in-place so we need to temp, either in a file or a variable

echo "$(tr -d '[:cntrl:]' < $RULESETS | tr -s '[:space:]')" > $RULESETS

# Beware that this *assumes* the used shell accepts variable sizes of >2Mb.

}

# Execution start

cd src

echo "Creating ruleset library..."

populate_rulesets

echo "Removing control characters, whitespace and comments..."

PRECRUSH=$(rulesize)

flatten_file

echo "Formatting..."

format_rulesets

echo "Final touches..."

# sed -i is not portable (GNU extension), but maybe we don't care.

sed -ir "$SED_TRIM_CMD" $RULESETS

POSTCRUSH=$(rulesize)

# All done, print summary

printf "Crushed %d bytes of rulesets into %d (delta %d)\n" \

$PRECRUSH $POSTCRUSH $((POSTCRUSH-PRECRUSH))

# Timestamp

touch -r chrome/content/rules $RULESETS

# We need to keep $RULESETS for makecrx.sh but the rest is of no further use

unset INDENT_CHAR TAG_DEFINITIONS SED_TRIM_CMD PRECRUSH POSTCRUSH

unset repeat_char format_rulesets rulesize populate_rulesets flatten_file

cd ..

# grep tests to ensure the sed magic worked (should find no matches):

#

# non-indenting double whitespace: '[^ ] \{2,\}'

# missing space after field: '="[^"]\+"[^ />]' # not perfect

# trailing whitespace: ' $' # pipe to | cat -A -

# malformed http(s) protocol text 'http[s?]\{,2\}[^:]//'

# random double+ slashes: '[^:;]//'

#