From 15efe56762c5fcdc5b37380e27c9414aefb97d75 Mon Sep 17 00:00:00 2001
From: Smittix <jamessmith1@outlook.com>
Date: Sun, 8 Feb 2026 16:00:31 +0000
Subject: [PATCH] Detect grgsm_scanner crash-on-startup and report to UI

grgsm_scanner exits in <300ms with osmo_fsm assertion error due to
libosmocore incompatibility. Added crash detection: if process exits
in <5s with non-zero code, counts as crash. After 3 crashes, stops
retrying and sends error to SSE stream so the UI can display it.

Also drains remaining queue items after process exits and logs exit
code and scan duration for diagnostics.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 routes/gsm_spy.py | 38 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 36 insertions(+), 2 deletions(-)

diff --git a/routes/gsm_spy.py b/routes/gsm_spy.py
index 4d70227..5949158 100644
--- a/routes/gsm_spy.py
+++ b/routes/gsm_spy.py
@@ -1218,6 +1218,7 @@ def scanner_thread(cmd, device_index):
     strongest_tower = None
     auto_monitor_triggered = False  # Moved outside loop - persists across scans
     scan_count = 0
+    crash_count = 0
     process = None
 
     try:
@@ -1266,7 +1267,8 @@ def scanner_thread(cmd, device_index):
                 stderr_thread.start()
 
                 # Process output with timeout
-                last_output = time.time()
+                scan_start = time.time()
+                last_output = scan_start
                 scan_timeout = 120  # 2 minute maximum per scan
 
                 while app_module.gsm_spy_scanner_running:
@@ -1326,6 +1328,15 @@ def scanner_thread(cmd, device_index):
                             logger.warning(f"Scan timeout after {scan_timeout}s")
                             break
 
+                # Drain remaining queue items after process exits
+                while not output_queue_local.empty():
+                    try:
+                        msg_type, line = output_queue_local.get_nowait()
+                        if line:
+                            logger.info(f"Scanner [{msg_type}] (drain): {line.strip()}")
+                    except queue.Empty:
+                        break
+
                 # Clean up process with timeout
                 if process.poll() is None:
                     logger.info("Terminating scanner process")
@@ -1333,7 +1344,30 @@ def scanner_thread(cmd, device_index):
                 else:
                     process.wait()  # Reap zombie
 
-                logger.info(f"Scan #{scan_count} complete")
+                exit_code = process.returncode
+                scan_duration = time.time() - scan_start
+                logger.info(f"Scan #{scan_count} complete (exit code: {exit_code}, duration: {scan_duration:.1f}s)")
+
+                # Detect crash pattern: process exits too quickly with no data
+                if scan_duration < 5 and exit_code != 0:
+                    crash_count += 1
+                    logger.error(
+                        f"grgsm_scanner crashed on startup (exit code: {exit_code}). "
+                        f"Crash count: {crash_count}. Check gr-gsm/libosmocore compatibility."
+                    )
+                    try:
+                        app_module.gsm_spy_queue.put_nowait({
+                            'type': 'error',
+                            'message': f'grgsm_scanner crashed (exit code: {exit_code}). '
+                                       'This may be a gr-gsm/libosmocore compatibility issue. '
+                                       'Try rebuilding gr-gsm from source.',
+                            'timestamp': time.strftime('%Y-%m-%dT%H:%M:%S')
+                        })
+                    except queue.Full:
+                        pass
+                    if crash_count >= 3:
+                        logger.error("grgsm_scanner crashed 3 times, stopping scanner")
+                        break
 
             except FileNotFoundError:
                 logger.error(