Update fallback-ap.sh

Reviewed-on: #14

fallback-ap.sh

@@ -14,19 +14,12 @@ set -e
 # and stays as plain constants.
 
 CONFIG_FILE="/etc/fallback-ap.conf"
-
+if [ -f "$CONFIG_FILE" ]; then source "$CONFIG_FILE"; fi
-# Load persisted settings from a previous install, if any. These are stored
-# under SAVED_* names (not FALLBACK_AP_*) specifically so that sourcing this
-# file can never clobber an explicit environment-variable override below.
-if [ -f "$CONFIG_FILE" ]; then
-    # shellcheck disable=SC1090
-    source "$CONFIG_FILE"
-fi
 
 WLAN0_IFACE="${FALLBACK_AP_IFACE:-${SAVED_IFACE:-wlan0}}"
 
 AP_NAME="${FALLBACK_AP_SSID:-${SAVED_SSID:-$HOSTNAME}}"
-AP_PASSWORD="${FALLBACK_AP_PASSWORD:-${SAVED_PASSWORD:-guesswhatitis}}"
+AP_PASSWORD="${FALLBACK_AP_PASSWORD:-${SAVED_PASSWORD:-abcd1234}}"
 AP_ENCRYPTION="${FALLBACK_AP_ENCRYPTION:-${SAVED_ENCRYPTION:-wpa-psk}}" # none | wpa-psk | sae
 
 FALLBACK_AP_CIDR="${FALLBACK_AP_CIDR:-${SAVED_CIDR:-10.10.10.1/24}}"
@@ -52,10 +45,10 @@ RECOVERY_WINDOW=20
 STATE_SETTLE_DELAY=1
 
 CONNECTION_NAME="Fallback AP"
-SERVICE_NAME="pi-fallback-ap"
+SERVICE_NAME="fallback-ap"
 SERVICE_FILE="/etc/systemd/system/$SERVICE_NAME.service"
 
-STATE_DIR="/var/lib/pi-fallback-ap"
+STATE_DIR="/var/lib/fallback-ap"
 LAST_WIFI_FILE="$STATE_DIR/last-wifi"
 LOCK_FILE="$STATE_DIR/lock"
 STATE_FILE="$STATE_DIR/state"
@@ -214,16 +207,6 @@ stop_ap() {
     return 0
 }
 
-
-# ==========================================================================
-# One tick of the control loop. Called once per second, always while
-# holding the wlan0 lock, so everything here runs to completion before
-# the next tick starts - there is no interleaving to race against.
-#
-# `last_attempt` is intentionally not declared `local` here: it lives in
-# run()'s scope and this function updates it directly (bash resolves it
-# via the caller's scope as long as nothing else shadows it).
-# ==========================================================================
 tick() {
     local now="$1"
 
@@ -252,8 +235,6 @@ tick() {
     clients="$(get_client_count)"
 
     if [ "$clients" -gt 0 ]; then
-        # Someone is using the AP right now. Leave it alone and push the
-        # next recovery attempt back so we don't kick them off.
         last_attempt="$now"
         return
     fi
@@ -264,9 +245,6 @@ tick() {
     fi
 }
 
-
-# Stop the AP, give NetworkManager a window to autoconnect to any known
-# network it can see, and bring the AP back if that doesn't happen.
 attempt_recovery() {
     log "No AP clients, checking for known Wi-Fi (AP down for up to ${RECOVERY_WINDOW}s)"
 
@@ -303,7 +281,6 @@ attempt_recovery() {
 
 save_config() {
     mkdir -p "$(dirname "$CONFIG_FILE")"
-
     cat > "$CONFIG_FILE" <<EOF
 SAVED_IFACE="$WLAN0_IFACE"
 SAVED_SSID="$AP_NAME"
@@ -313,8 +290,6 @@ SAVED_CIDR="$FALLBACK_AP_CIDR"
 SAVED_DHCP_START_OCTET="$FALLBACK_AP_DHCP_START_OCTET"
 SAVED_DHCP_END_OCTET="$FALLBACK_AP_DHCP_END_OCTET"
 EOF
-
-    # Contains the AP passphrase - keep it out of reach of other users.
     chmod 600 "$CONFIG_FILE"
 }
 
@@ -539,13 +514,6 @@ run() {
 
     log "Fallback AP service started"
     log "Script: $SCRIPT_PATH"
-
-    # Open the lock fd once for the life of the process. Using `flock`
-    # directly against this fd (instead of wrapping each tick in its own
-    # `( ... ) 9>"$LOCK_FILE"` subshell) matters: any variable a tick
-    # updates - like last_attempt below - has to survive into the next
-    # loop iteration, and a subshell would silently throw those updates
-    # away when it exits.
     exec 9>"$LOCK_FILE"
 
     flock 9

install.sh

@@ -13,17 +13,28 @@ fi
 
 prompt() {
     local __var="$1" __question="$2" __default="$3" __answer=""
-    if [ -e /dev/tty ]; then
+    read -r -p "$__question [$__default]: " __answer < /dev/tty || __answer=""
-        read -r -p "$__question [$__default]: " __answer 2>/dev/null < /dev/tty > /dev/tty || __answer=""
-    fi
     printf -v "$__var" '%s' "${__answer:-$__default}"
 }
 
-[ -z "${FALLBACK_AP_SSID:-}" ]              && prompt FALLBACK_AP_SSID "Access point SSID" "$(hostname)"
+EXISTING_CONFIG="/etc/fallback-ap.conf"
-[ -z "${FALLBACK_AP_PASSWORD:-}" ]          && prompt FALLBACK_AP_PASSWORD "Access point passphrase" "guesswhatitis"
+
-[ -z "${FALLBACK_AP_CIDR:-}" ]              && prompt FALLBACK_AP_CIDR "Access point subnet (CIDR)" "10.10.10.1/24"
+if [ -f "$EXISTING_CONFIG" ]; then
-[ -z "${FALLBACK_AP_DHCP_START_OCTET:-}" ]  && prompt FALLBACK_AP_DHCP_START_OCTET "DHCP range start (last octet)" "100"
+    # shellcheck disable=SC1090
-[ -z "${FALLBACK_AP_DHCP_END_OCTET:-}" ]    && prompt FALLBACK_AP_DHCP_END_OCTET "DHCP range end (last octet)" "250"
+    source "$EXISTING_CONFIG"
+fi
+
+DEFAULT_SSID="${SAVED_SSID:-$(hostname)}"
+DEFAULT_PASSWORD="${SAVED_PASSWORD:-abcd1234}"
+DEFAULT_CIDR="${SAVED_CIDR:-10.10.10.1/24}"
+DEFAULT_DHCP_START_OCTET="${SAVED_DHCP_START_OCTET:-100}"
+DEFAULT_DHCP_END_OCTET="${SAVED_DHCP_END_OCTET:-250}"
+
+[ -z "${FALLBACK_AP_SSID:-}" ]              && prompt FALLBACK_AP_SSID "Access point SSID" "$DEFAULT_SSID"
+[ -z "${FALLBACK_AP_PASSWORD:-}" ]          && prompt FALLBACK_AP_PASSWORD "Access point passphrase" "$DEFAULT_PASSWORD"
+[ -z "${FALLBACK_AP_CIDR:-}" ]              && prompt FALLBACK_AP_CIDR "Access point subnet (CIDR)" "$DEFAULT_CIDR"
+[ -z "${FALLBACK_AP_DHCP_START_OCTET:-}" ]  && prompt FALLBACK_AP_DHCP_START_OCTET "DHCP range start (last octet)" "$DEFAULT_DHCP_START_OCTET"
+[ -z "${FALLBACK_AP_DHCP_END_OCTET:-}" ]    && prompt FALLBACK_AP_DHCP_END_OCTET "DHCP range end   (last octet)" "$DEFAULT_DHCP_END_OCTET"
 
 export FALLBACK_AP_SSID FALLBACK_AP_PASSWORD FALLBACK_AP_CIDR FALLBACK_AP_DHCP_START_OCTET FALLBACK_AP_DHCP_END_OCTET