feat: add plasma-face-unlock

src/lib/config.sh

@@ -0,0 +1,132 @@
+# shellcheck shell=bash
+#
+# Reading and writing the settings files.
+#
+# Two of them, in the same format: ~/.config/plasma-face-unlock/config for
+# what this user wants from the lock screen and the bubble, and
+# /etc/plasma-face-unlock/config for what the daemon does (which camera, how
+# strict), which only root writes. Neither is meant to be edited by hand:
+# every option is in the menu.
+#
+# Both are parsed rather than sourced. One "Key=Value" per line, '#'
+# comments. The daemon and the agent read them with the same rules (see
+# src/core/keyvalue.cpp).
+
+declare -A PFU_KV_CACHE=()
+
+# _pfu_kv_lookup <file> <Key> [default]
+# Result in PFU_KV_VALUE. Assigning rather than printing matters on the
+# settings screen, which reads every key on every frame: a command
+# substitution there is a fork, and forks are the whole cost of a redraw.
+PFU_KV_VALUE=''
+
+_pfu_kv_lookup() {
+	local file="$1" key="$2" default="${3:-}" val='' line content
+
+	PFU_KV_VALUE="$default"
+	[[ -r $file ]] || return 0
+
+	if [[ -n ${PFU_KV_CACHE[$file]+set} ]]; then
+		content="${PFU_KV_CACHE[$file]}"
+	else
+		content="$(< "$file")"
+		PFU_KV_CACHE[$file]="$content"
+	fi
+
+	while IFS= read -r line; do
+		[[ $line == *"$key"* ]] || continue
+		[[ $line =~ ^[[:space:]]*"$key"[[:space:]]*=(.*)$ ]] || continue
+		val="${BASH_REMATCH[1]}"
+	done <<< "$content"
+
+	val="${val%%#*}"
+	val="${val#"${val%%[![:space:]]*}"}"
+	val="${val%"${val##*[![:space:]]}"}"
+	val="${val%\"}"
+	val="${val#\"}"
+
+	[[ -n $val ]] && PFU_KV_VALUE="$val"
+	return 0
+}
+
+pfu_is_true() {
+	case "${1,,}" in
+		yes|y|true|1|on|enabled) return 0 ;;
+		*) return 1 ;;
+	esac
+}
+
+# pfu_kv_set <file> <Key> <Value> <header line>
+pfu_kv_set() {
+	local file="$1" key="$2" value="$3" header="$4" tmp
+
+	if [[ ! -e $file ]]; then
+		mkdir -p "$(dirname "$file")" || return 1
+		{
+			printf '# %s\n' "$header"
+			printf '#\n'
+			printf '# Written by `%s`. Nothing here needs editing by hand:\n' "$PFU_NAME"
+			printf '# every option is in the menu.\n'
+		} > "$file" || return 1
+	fi
+	[[ -w $file ]] || return 1
+
+	tmp="$(mktemp "${file}.XXXXXX")" || return 1
+	chmod --reference="$file" "$tmp" 2>/dev/null || chmod 0644 "$tmp"
+
+	if grep -qE "^[[:space:]]*#?[[:space:]]*${key}[[:space:]]*=" "$file"; then
+		awk -v key="$key" -v value="$value" '
+			!done && $0 ~ "^[[:space:]]*#?[[:space:]]*" key "[[:space:]]*=" {
+				print key "=" value; done = 1; next
+			}
+			# drop any further occurrences so the file cannot grow duplicates
+			$0 ~ "^[[:space:]]*" key "[[:space:]]*=" { next }
+			{ print }
+		' "$file" > "$tmp" || { rm -f "$tmp"; return 1; }
+	else
+		cat "$file" > "$tmp" || { rm -f "$tmp"; return 1; }
+		printf '%s=%s\n' "$key" "$value" >> "$tmp"
+	fi
+
+	# Replaced, not rewritten in place: the agent watches the directory and
+	# picks up the new file the moment it lands.
+	mv -f "$tmp" "$file"
+	unset 'PFU_KV_CACHE[$file]'
+}
+
+# ---------------------------------------------------------------------------
+# This user's settings
+# ---------------------------------------------------------------------------
+
+pfu_config_get() {
+	_pfu_kv_lookup "$PFU_CONFIG" "$@"
+	printf '%s\n' "$PFU_KV_VALUE"
+}
+
+pfu_config_set() {
+	pfu_kv_set "$PFU_CONFIG" "$1" "$2" "$PFU_PRETTY"
+}
+
+# ---------------------------------------------------------------------------
+# The system settings (read by anybody, written by root)
+# ---------------------------------------------------------------------------
+
+pfu_sys_get() {
+	_pfu_kv_lookup "$PFU_SYSCONFIG" "$@"
+	printf '%s\n' "$PFU_KV_VALUE"
+}
+
+# pfu_config_load
+# Everything the menu shows, resolved once per screen.
+pfu_config_load() {
+	PFU_KV_CACHE=()
+
+	_pfu_kv_lookup "$PFU_CONFIG" Enabled no;          CFG_ENABLED=no;  pfu_is_true "$PFU_KV_VALUE" && CFG_ENABLED=yes
+	_pfu_kv_lookup "$PFU_CONFIG" LockScreen yes;      CFG_LOCK=no;     pfu_is_true "$PFU_KV_VALUE" && CFG_LOCK=yes
+	_pfu_kv_lookup "$PFU_CONFIG" Sudo no;             CFG_SUDO=no;     pfu_is_true "$PFU_KV_VALUE" && CFG_SUDO=yes
+	_pfu_kv_lookup "$PFU_CONFIG" Polkit no;           CFG_POLKIT=no;   pfu_is_true "$PFU_KV_VALUE" && CFG_POLKIT=yes
+
+	_pfu_kv_lookup "$PFU_SYSCONFIG" Liveness heavy;   CFG_LIVENESS="$PFU_KV_VALUE"
+	_pfu_kv_lookup "$PFU_SYSCONFIG" Camera auto;      CFG_CAMERA="$PFU_KV_VALUE"
+	return 0
+}