clipmenud
#!/bin/bash
: "${CM_ONESHOT=0}"
: "${CM_OWN_CLIPBOARD=1}"
: "${CM_DEBUG=0}"
: "${CM_DIR="${XDG_RUNTIME_DIR-"${TMPDIR-/tmp}"}"}"
: "${CM_MAX_CLIPS=1000}"
# Shellcheck is mistaken here, this is used later as lowercase.
# shellcheck disable=SC2153
: "${CM_SELECTIONS=clipboard primary}"
major_version=5
cache_dir=$CM_DIR/clipmenu.$major_version.$USER/
cache_file_prefix=$cache_dir/line_cache
lock_file=$cache_dir/lock
lock_timeout=2
has_clipnotify=0
# This comes from the environment, so we rely on word splitting.
# shellcheck disable=SC2206
cm_selections=( $CM_SELECTIONS )
xsel_log=/dev/null
for file in /proc/self/fd/2 /dev/stderr; do
[[ -f "$file" ]] || continue
# In Linux, it's not possible to write to a socket represented by a file
# (for example, /dev/stderr or /proc/self/fd/2). See issue #54.
[[ -f "$(readlink "$file")" ]] || continue
xsel_log="$file"
break
done
_xsel() {
timeout 1 xsel --logfile "$xsel_log" "$@"
}
get_first_line() {
# Args:
# - , the file or data
# - , optional, the line length limit
data=${1?}
line_length_limit=${2-300}
# We look for the first line matching regex /./ here because we want the
# first line that can provide reasonable context to the user. That is, if
# you have 5 leading lines of whitespace, displaying " (6 lines)" is much
# less useful than displaying "foo (6 lines)", where "foo" is the first
# line in the entry with actionable context.
awk -v limit="$line_length_limit" '
BEGIN { printed = 0; }
printed == 0 && NF {
{{&blob}} = substr({{&blob}}, 0, limit);
printf("%s", {{&blob}});
printed = 1;
}
END {
if (NR > 1) {
print " (" NR " lines)";
} else {
printf("\n");
}
}' <<< "$data"
}
debug() {
if (( CM_DEBUG )); then
printf '%s\n' "$@" >&2
fi
}
element_in() {
local item element
item=""
for element in "${@:2}"; do
if [[ "$item" == "$element" ]]; then
return 0
fi
done
return 1
}
if [[ == --help ]] || [[ == -h ]]; then
cat << 'EOF'
clipmenud is the daemon that collects and caches what's on the clipboard.
when you want to select a clip.
Environment variables:
- $CM_ONESHOT: run once immediately, do not loop (default: 0)
- $CM_DEBUG: turn on debugging output (default: 0)
- $CM_OWN_CLIPBOARD: take ownership of the clipboard (default: 1)
- $CM_MAX_CLIPS: maximum number of clips to store, 0 for inf (default: 1000)
- $CM_DIR: specify the base directory to store the cache dir in (default: $XDG_RUNTIME_DIR, $TMPDIR, or /tmp)
- $CM_SELECTIONS: space separated list of the selections to manage (default: "clipboard primary")
EOF
exit 0
fi
# It's ok that this only applies to the final directory.
# shellcheck disable=SC2174
mkdir -p -m0700 "$cache_dir"
declare -A last_data
declare -A last_filename
declare -A last_cache_file_output
command -v clipnotify >/dev/null 2>&1 && has_clipnotify=1
if ! (( has_clipnotify )); then
echo "WARN: Consider installing clipnotify for better performance." >&2
echo "WARN: See https://github.com/cdown/clipnotify." >&2
fi
exec {lock_fd}> "$lock_file"
sleep_cmd=(sleep "${CM_SLEEP:-0.5}")
while true; do
if ! (( CM_ONESHOT )); then
if (( has_clipnotify )); then
# Fall back to polling if clipnotify fails
clipnotify || "${sleep_cmd[@]}"
else
# Use old polling method
"${sleep_cmd[@]}"
fi
fi
if ! flock -x -w "$lock_timeout" "$lock_fd"; then
if (( CM_ONESHOT )); then
printf 'ERROR: %s\n' 'Timed out waiting for lock' >&2
exit 1
else
printf 'ERROR: %s\n' \
'Timed out waiting for lock, skipping this run' >&2
continue
fi
fi
for selection in "${cm_selections[@]}"; do
cache_file=${cache_file_prefix}_$selection
data=$(_xsel -o --"$selection"; printf x)
debug "Data before stripping: $data"
# We add and remove the x so that trailing newlines are not stripped.
# Otherwise, they would be stripped by the very nature of how POSIX
# defines command substitution.
data=${data%x}
debug "Data after stripping: $data"
if [[ $data != *[^[:space:]]* ]]; then
debug "Skipping as clipboard is only blank"
continue
fi
if [[ ${last_data[$selection]} == "$data" ]]; then
debug 'Skipping as last selection is the same as this one'
continue
fi
# If we were in the middle of doing a selection when the previous poll
# ran, then we may have got a partial clip.
possible_partial=${last_data[$selection]}
if [[ $possible_partial && $data == "$possible_partial"* ]] ||
[[ $possible_partial && $data == *"$possible_partial" ]]; then
debug "$possible_partial is a possible partial of $data"
debug "Removing ${last_filename[$selection]}"
previous_size=$(wc -c <<< "${last_cache_file_output[$selection]}")
truncate -s -"$previous_size" "$cache_file"
rm -- "${last_filename[$selection]}"
fi
last_data[$selection]=$data
last_filename[$selection]=$filename
first_line=$(get_first_line "$data")
debug "New clipboard entry on $selection selection: \"$first_line\""
cache_file_output="$(date +%s%N) $first_line"
filename="$cache_dir/$(cksum <<< "$first_line")"
# Recover without restart if we deleted the entire clip dir.
# It's ok that this only applies to the final directory.
# shellcheck disable=SC2174
mkdir -p -m0700 "$cache_dir"
debug "Writing $data to $filename"
printf '%s' "$data" > "$filename"
debug "Writing $cache_file_output to $cache_file"
printf '%s\n' "$cache_file_output" >> "$cache_file"
last_cache_file_output[$selection]=$cache_file_output
if (( CM_OWN_CLIPBOARD )) && [[ $selection != primary ]] &&
element_in clipboard "${cm_selections[@]}"; then
# Take ownership of the clipboard, in case the original application
# is unable to serve the clipboard request (due to being suspended,
# etc).
#
# Primary is excluded from the change of ownership as applications
# sometimes act up if clipboard focus is taken away from them --
# for example, urxvt will unhilight text, which is undesirable.
#
# We can't colocate this with the above copying code because
# https://github.com/cdown/clipmenu/issues/34 requires knowing if
# we would skip first.
_xsel -o --clipboard | _xsel -i --clipboard
fi
if (( CM_MAX_CLIPS )) && [[ -f $cache_file ]]; then
mapfile -t to_remove < <(
head -n -"$CM_MAX_CLIPS" "$cache_file" |
while read -r line; do cksum <<< "${line#* }"; done
)
num_to_remove="${#to_remove[@]}"
if (( num_to_remove )); then
debug "Removing $num_to_remove old clips"
rm -- "${to_remove[@]/#/"$cache_dir/"}"
trunc_tmp=$(mktemp)
tail -n "$CM_MAX_CLIPS" "$cache_file" | uniq > "$trunc_tmp"
mv -- "$trunc_tmp" "$cache_file"
fi
fi
done
flock -u "$lock_fd"
if (( CM_ONESHOT )); then
debug 'Oneshot mode enabled, exiting'
break
fi
done