From ccb40ae635e2bf5b5d414f2e4fb50d1ea5ce678f Mon Sep 17 00:00:00 2001
From: Krzysztof kuhy Rudnicki <krzysztofrudnicki0@gmail.com>
Date: Fri, 27 Mar 2026 16:04:50 +0100
Subject: [PATCH] fix: phone focus mode daemon survival across reboots

- Fix PID reuse bug: validate /proc/cmdline before assuming daemon is running
- Add log rotation using existing LOG_MAX_LINES config (was 7MB/70K lines)
- chmod 666 state files on init and deploy to prevent permission drift
---
 phone_focus_mode/deploy.sh       |  5 +++--
 phone_focus_mode/focus_daemon.sh | 26 +++++++++++++++++++++++---
 2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/phone_focus_mode/deploy.sh b/phone_focus_mode/deploy.sh
index 2bee1fb..6605df8 100755
--- a/phone_focus_mode/deploy.sh
+++ b/phone_focus_mode/deploy.sh
@@ -143,8 +143,9 @@ do_deploy() {
     echo "[5/6] Setting permissions..."
     adb_root "chmod 755 $REMOTE_DIR/config.sh $REMOTE_DIR/focus_daemon.sh $REMOTE_DIR/focus_ctl.sh" || true
     adb_root "chmod 755 /data/adb/service.d/99-focus-mode.sh"
-    adb_root "touch $REMOTE_DIR/disabled_by_focus.txt"
-    adb_root "touch $REMOTE_DIR/focus_mode.log"
+    adb_root "touch $REMOTE_DIR/disabled_by_focus.txt $REMOTE_DIR/focus_mode.log"
+    # State files need 666 so the daemon can write regardless of SELinux context drift
+    adb_root "chmod 666 $REMOTE_DIR/disabled_by_focus.txt $REMOTE_DIR/focus_mode.log" || true
 
     echo "[6/6] Starting daemon..."
     # Stop existing daemon, then start fresh
diff --git a/phone_focus_mode/focus_daemon.sh b/phone_focus_mode/focus_daemon.sh
index 1a05526..6c2ceb5 100755
--- a/phone_focus_mode/focus_daemon.sh
+++ b/phone_focus_mode/focus_daemon.sh
@@ -18,10 +18,15 @@ acquire_lock() {
         local old_pid
         old_pid="$(cat "$PIDFILE")"
         if kill -0 "$old_pid" 2>/dev/null; then
-            echo "Daemon already running (PID $old_pid), exiting."
-            exit 0
+            # Verify the PID is actually a focus_daemon, not a reused PID
+            local cmdline
+            cmdline="$(cat /proc/$old_pid/cmdline 2>/dev/null | tr '\0' ' ')"
+            if echo "$cmdline" | grep -q "focus_daemon"; then
+                echo "Daemon already running (PID $old_pid), exiting."
+                exit 0
+            fi
         fi
-        # Stale pidfile
+        # Stale or reused pidfile
         rm -f "$PIDFILE"
     fi
     echo $$ > "$PIDFILE"
@@ -34,6 +39,16 @@ log() {
     echo "[$ts] $1" >> "$LOG_FILE"
 }
 
+rotate_log() {
+    local lines
+    lines="$(wc -l < "$LOG_FILE" 2>/dev/null || echo 0)"
+    if [ "$lines" -gt "$LOG_MAX_LINES" ]; then
+        local tmp="$LOG_FILE.tmp"
+        tail -n "$LOG_MAX_LINES" "$LOG_FILE" > "$tmp"
+        mv "$tmp" "$LOG_FILE"
+    fi
+}
+
 # ---- Build helper files for fast package checks ----
 
 build_whitelist_file() {
@@ -73,6 +88,8 @@ init() {
     mkdir -p "$STATE_DIR"
     touch "$LOG_FILE"
     touch "$DISABLED_APPS_FILE"
+    # Ensure state files are writable (survives reboot / permission drift)
+    chmod 666 "$LOG_FILE" "$DISABLED_APPS_FILE" "$PIDFILE" 2>/dev/null
 
     if [ "$HOME_LAT" = "0.000000" ] && [ "$HOME_LON" = "0.000000" ]; then
         log "ERROR: Home coordinates not set! Edit config.sh first."
@@ -81,6 +98,7 @@ init() {
 
     build_whitelist_file
     build_sysprotect_file
+    rotate_log
 
     if [ -f "$MODE_FILE" ]; then
         CURRENT_MODE="$(cat "$MODE_FILE")"
@@ -261,6 +279,8 @@ main() {
         else
             sleep "$CHECK_INTERVAL_NORMAL"
         fi
+
+        rotate_log
     done
 }