Track device connection and capture gaps; surface sniff error flags

frontend/index.html

@@ -76,6 +76,9 @@ body { font: 14px/1.5 system-ui, sans-serif; background: var(--bg); color: var(-
 .header-title a { color: var(--accent); text-decoration: none; }
 .header-title a:hover { text-decoration: underline; }
 .header-right { margin-left: auto; display: flex; align-items: center; gap: 12px; padding: 8px 16px; }
+.capture-chip { font-size: 12px; font-weight: 600; padding: 4px 10px; border-radius: 12px; white-space: nowrap; }
+.capture-chip.live { color: var(--green); background: var(--accent-bg); }
+.capture-chip.warn { color: var(--warn); background: var(--warning-bg); }
 .header-right a { color: var(--link); text-decoration: none; font-size: 13px; }
 .header-right a:hover { color: var(--link-hover); }
 .header-right button { padding: 4px 10px; font-size: 14px; cursor: pointer; background: var(--bg-input); border: 1px solid var(--border); border-radius: 4px; color: var(--text); }
@@ -115,6 +118,11 @@ body { font: 14px/1.5 system-ui, sans-serif; background: var(--bg); color: var(-
 .apdu-sw.sw-pending { color: var(--accent); }
 .apdu-sw.sw-warn { color: var(--warn); }
 .apdu-sw.sw-error { color: var(--error); }
+.apdu-err { color: var(--error); white-space: nowrap; }
+.apdu-gap { background: var(--warning-bg); border-bottom: 1px solid var(--warn); }
+.apdu-gap .apdu-type { color: var(--warn); }
+.apdu-gap .apdu-data { color: var(--warn); }
+.device-warn { padding: 8px 12px; font-size: 12px; color: var(--warn); background: var(--warning-bg); border-bottom: 1px solid var(--warn); }
 
 /* APDU detail panel */
 .apdu-detail { display: flex; flex-direction: column; max-height: 40%; overflow-y: auto; border-top: 2px solid var(--accent); background: var(--bg-panel); flex-shrink: 0; }
@@ -232,6 +240,7 @@ body { font: 14px/1.5 system-ui, sans-serif; background: var(--bg); color: var(-
     </div>
     <div class="header-title">SIM-ME <a href="https://osmocom.org/projects/baseband/wiki/GSMTAP" target="_blank" rel="noopener">GSMTAP</a> <span data-l10n="trace analyser">trace analyser</span> <span class="pwa-version" id="pwa-version"></span></div>
     <div class="header-right">
+        <span class="capture-chip" id="capture-chip" style="display:none"></span>
         <button id="install-btn" data-l10n="Install PWA">Install PWA</button>
         <a href="https://github.com/anttro/simtrace2-pysniff" target="_blank" rel="noopener">GitHub</a>
         <button id="lang-btn" onclick="toggleLang()" title="Language / Язык">EN</button>
@@ -267,6 +276,7 @@ body { font: 14px/1.5 system-ui, sans-serif; background: var(--bg); color: var(-
         <span><span class="status-dot off" id="status-dot"></span><span id="status-text" data-l10n="Not connected">Not connected</span></span>
         <span id="msg-count" style="color:var(--text-muted);">0 messages</span>
     </div>
+    <div class="device-warn" id="device-warn" style="display:none">⚠ <span id="device-warn-text"></span></div>
 </div>
 
 <!-- Sessions Panel -->
@@ -348,6 +358,7 @@ const STATE = {
     serverName: '',
     serverVersion: '',
     captureMode: '',
+    deviceConnected: null,
 };
 
 const API_BASE = () => STATE.serverUrl;
@@ -378,6 +389,7 @@ function ins_label(msg) {
     if (msg.type === 'pps') return 'PPS';
     if (msg.type === 'change') return 'STATE CHANGE';
     if (msg.type === 'fidi') return 'FIDI';
+    if (msg.type === 'gap') return 'CAPTURE GAP';
     const d = msg.data;
     if (d && d.length >= 2) {
         const ins = d.slice(2, 4);
@@ -391,6 +403,7 @@ function _fallback_label(msg) {
     if (msg.type === 'pps') return 'PPS';
     if (msg.type === 'change') return 'STATE CHANGE';
     if (msg.type === 'fidi') return 'FIDI';
+    if (msg.type === 'gap') return 'CAPTURE GAP';
     const data = msg.data;
     if (data && data.length >= 2) {
         const ins = data.slice(2, 4);
@@ -458,10 +471,16 @@ function data_text(m) {
 }
 
 function cmd_description(m) {
+    if (m.type === 'gap') return t('device disconnected — messages may be missing');
     if (m.decoded && m.decoded.summary) return m.decoded.summary;
     return data_text(m);
 }
 
+function error_names(m) {
+    const d = m.decoded;
+    return (d && Array.isArray(d.errors) && d.errors.length) ? d.errors : null;
+}
+
 function sw_text(m) {
     const d = m.decoded;
     if (!d || !d.sw) return '';
@@ -834,6 +853,7 @@ function atrPpsRows(decoded) {
         if (decoded.note) rows.push(['Note', decoded.note]);
     }
     rows.push(['Raw', (decoded.raw || '')]);
+    if (decoded.errors) rows.push(['Errors', decoded.errors.join(', ')]);
     return rows;
 }
 
@@ -845,6 +865,12 @@ function showDetail(msg, entry) {
     const d = el('apdu-detail');
     const decoded = msg.decoded;
 
+    if (msg.type === 'gap') {
+        d.innerHTML = `<div class="detail-header"><strong>Capture Gap</strong><span style="color:var(--text-muted)">${fmt_elapsed(msg.elapsed)}</span></div>
+            <div class="detail-body" style="color:var(--warn);">⚠ ${t('The device disconnected and reconnected — some APDUs may be missing from this trace.')}</div>`;
+        return;
+    }
+
     if (!decoded) {
         d.innerHTML = `<div class="detail-header"><strong>${ins_label(msg)}</strong><span style="color:var(--text-muted)">${fmt_elapsed(msg.elapsed)}</span></div>
             <div class="detail-body" style="color:var(--text-muted);">No decoded data available for this message type.</div>`;
@@ -959,6 +985,7 @@ function showDetail(msg, entry) {
             ${responseRows(decoded.response)}
             ${fileRows(decoded.file)}
             ${sw}
+            ${decoded.errors ? `<tr><td class="label">Errors</td><td class="value" style="color:var(--error)">${decoded.errors.join(', ')}</td></tr>` : ''}
         </table>
     </div>`;
 }
@@ -1213,13 +1240,23 @@ function renderMessages(skipScroll) {
     }
 
     list.innerHTML = filtered.map(({ m, idx }) => {
+        if (m.type === 'gap') {
+            return `<div class="apdu-entry apdu-gap" data-idx="${idx}">
+                <span class="apdu-time">${fmt_elapsed(m.elapsed)}</span>
+                <span class="apdu-type">⚠ CAPTURE GAP</span>
+                <span class="apdu-data">${cmd_description(m)}</span>
+            </div>`;
+        }
         const label = ins_label(m);
         const typeCls = m.type === 'atr' ? 'atr' : m.type === 'pps' ? 'pps' : '';
+        const errs = error_names(m);
+        const errBadge = errs ? `<span class="apdu-err" title="${errs.join(', ')}">⚠</span>` : '';
         return `<div class="apdu-entry" data-idx="${idx}">
             <span class="apdu-time">${fmt_elapsed(m.elapsed)}</span>
             <span class="apdu-type ${typeCls}">${label}</span>
             <span class="apdu-sw ${sw_class(m)}">${sw_text(m)}</span>
             <span class="apdu-data">${cmd_description(m)}</span>
+            ${errBadge}
         </div>`;
     }).join('');
 
@@ -1246,17 +1283,48 @@ function updateStatus() {
         text.textContent = t('Not connected');
     }
     count.textContent = t('{n} messages').replace('{n}', STATE.messages.length);
+    updateDeviceWarn();
+    updateCaptureChip();
+}
+
+function updateCaptureChip() {
+    const chip = el('capture-chip');
+    if (!chip) return;
+    const disconnected = STATE.captureMode === 'direct' && STATE.captureActive && STATE.deviceConnected === false;
+    if (disconnected) {
+        chip.style.display = '';
+        chip.className = 'capture-chip warn';
+        chip.textContent = '⚠ ' + t('device disconnected — reconnecting…');
+    } else if (STATE.captureActive) {
+        chip.style.display = '';
+        chip.className = 'capture-chip live';
+        chip.textContent = '● ' + t('LIVE') + ' · ' + t('{n} messages').replace('{n}', STATE.messages.length);
+    } else {
+        chip.style.display = 'none';
+    }
+}
+
+function updateDeviceWarn() {
+    const warn = el('device-warn');
+    if (!warn) return;
+    const disconnected = STATE.captureMode === 'direct' && STATE.captureActive && STATE.deviceConnected === false;
+    if (disconnected) {
+        warn.style.display = '';
+        el('device-warn-text').textContent = t('device disconnected — reconnecting…');
+    } else {
+        warn.style.display = 'none';
+    }
 }
 
 // ──────────────────── Live Polling ────────────────────
 let _lastAfter = 0;
 
 function startPolling() {
-    _lastAfter = 0;
     if (STATE.livePoller) return;
     STATE.livePoller = setInterval(async () => {
         try {
             const data = await API.getLatest(_lastAfter);
+            STATE.deviceConnected = data.device_connected;
             if (data.active) {
                 STATE.captureActive = true;
                 STATE.currentSessionId = data.session_id;
@@ -1289,6 +1357,7 @@ async function startCapture() {
         STATE.captureActive = true;
         STATE.currentSessionId = data.session_id;
         STATE.messages = [];
+        _lastAfter = 0;
         buildTypeCounts();
         buildTraceMap();
         renderSidePanel();
@@ -1426,6 +1495,7 @@ async function importPcapFile(file) {
 }
 
 async function loadSession(id) {
+    if (STATE.captureActive && !confirm(t('Opening a session stops the active capture. Continue?'))) return;
     try {
         // Stop any active capture so it can't write into the session being viewed.
         await API.stopCapture();
@@ -1563,6 +1633,7 @@ function connectServer() {
 }
 
 function disconnectServer() {
+    if (STATE.captureActive && !confirm(t('Capture is still running on the server — it will continue after you disconnect. Disconnect?'))) return;
     if (_connTimer) {
         clearInterval(_connTimer);
         _connTimer = null;
@@ -1585,10 +1656,6 @@ function disconnectServer() {
     btn.classList.add('disconnected');
     updateCaptureButton();
     stopPolling();
-    if (STATE.captureActive) {
-        STATE.captureActive = false;
-        STATE.currentSessionId = null;
-    }
     renderTraceEmptyState();
 }
 
@@ -1599,6 +1666,7 @@ async function checkConnection() {
         STATE.captureMode = data.capture_mode || '';
         STATE.serverName = data.server || 'simtrace-analyser-server';
         STATE.serverVersion = data.version || '';
+        STATE.deviceConnected = data.device_connected;
         el('conn-status').textContent = connectionStatusText();
         el('conn-status').className = 'conn-status connected';
         updateVersionWarn(data.version);
@@ -1610,8 +1678,18 @@ async function checkConnection() {
         el('status-dot').className = 'status-dot ' + (data.capture_active ? 'live' : 'paused');
         el('status-text').textContent = data.capture_active ? t('Capturing') : t('Connected');
         if (data.capture_active) {
+            if (data.session_id && data.session_id !== STATE.currentSessionId) {
+                // A different capture session than the one we were viewing —
+                // reset the stream so we re-fetch it from the start.
+                STATE.currentSessionId = data.session_id;
+                STATE.messages = [];
+                _lastAfter = 0;
+            }
             STATE.captureActive = true;
             STATE.currentSessionId = data.session_id;
+            startPolling();
+        } else {
+            STATE.captureActive = false;
         }
         updateCaptureButton();
         renderTraceEmptyState();
@@ -1734,6 +1812,12 @@ const LANG_RU = {
     'Import PCAP': 'Импорт PCAP',
     'New capture': 'Новый захват',
     'Server': 'Сервер',
+    'device disconnected — reconnecting…': 'устройство отключено — переподключение…',
+    'device disconnected — messages may be missing': 'устройство отключалось — сообщения могли быть потеряны',
+    'The device disconnected and reconnected — some APDUs may be missing from this trace.': 'Устройство отключалось и переподключалось — часть APDU может отсутствовать в трейсе.',
+    'LIVE': 'В ЭФИРЕ',
+    'Opening a session stops the active capture. Continue?': 'Открытие сессии остановит активный захват. Продолжить?',
+    'Capture is still running on the server — it will continue after you disconnect. Disconnect?': 'Захват всё ещё выполняется на сервере — он продолжится после отключения. Отключиться?',
     'Same origin': 'Тот же источник',
     'Custom URL': 'Свой URL',
     'Connect': 'Подключить',

simtrace2_pysniff/__main__.py

@@ -55,9 +55,6 @@ def build_parser():
     p.add_argument('--vendor', type=lambda x: int(x, 16),
                    default=0x1d50, metavar='HEX',
                    help='USB vendor ID (default: 0x1d50)')
-    p.add_argument('--product', type=lambda x: int(x, 16),
-                   default=None, metavar='HEX',
-                   help='USB product ID (default: auto-detect)')
 
     rec = p.add_argument_group('recovery options')
     rec.add_argument('--no-reconnect', action='store_true',
@@ -112,6 +109,7 @@ def main():
         reconnect_delay_max=args.reconnect_delay_max,
         backoff_factor=args.backoff_factor,
         inactivity_timeout=args.inactivity_timeout,
+        vendor_id=args.vendor,
     )
 
     exiting = False

simtrace2_pysniff/device.py

@@ -45,13 +45,7 @@ def find_sniffer_device(vendor_id=USB_VENDOR_OPENMOKO):
 
     Returns a ``usb.core.Device`` on success, or ``None``.
     """
-    devices = list(usb.core.find(
-        find_all=True,
-        idVendor=vendor_id,
-        custom_match=lambda d: (
-            True
-        ),
-    ))
+    devices = list(usb.core.find(find_all=True, idVendor=vendor_id))
 
     for dev in devices:
         for cfg in dev:
@@ -71,7 +65,9 @@ def _get_ep_addrs(dev):
                 intf.bInterfaceSubClass == SIMTRACE_SNIFFER_USB_SUBCLASS):
             for ep in intf:
                 addr = ep.bEndpointAddress
-                if addr & 0x80:  # IN endpoint
+                # BULK IN endpoint only — the interrupt IN endpoint carries
+                # cardem notifications, not sniff data.
+                if addr & 0x80 and ep.bmAttributes & 0x03 == 0x02:
                     return addr
     return None
 
@@ -100,16 +96,19 @@ class SniffSession:
                  reconnect_delay_min=1.0,
                  reconnect_delay_max=30.0,
                  backoff_factor=1.5,
-                 inactivity_timeout=0.0):
+                 inactivity_timeout=0.0,
+                 vendor_id=USB_VENDOR_OPENMOKO):
         self._reconnect = reconnect
         self._reconnect_delay_min = reconnect_delay_min
         self._reconnect_delay_max = reconnect_delay_max
         self._backoff_factor = backoff_factor
         self._inactivity_timeout = inactivity_timeout
+        self._vendor_id = vendor_id
 
         self._dev = None
         self._devh = None
         self._ep_in = None
+        self._connected = False
         self._last_msg_time = 0.0
         self._disconnect_count = 0
 
@@ -121,7 +120,7 @@ class SniffSession:
         if self._devh is not None:
             return
 
-        dev = find_sniffer_device()
+        dev = find_sniffer_device(vendor_id=self._vendor_id)
         if dev is None:
             raise DeviceDisconnected('No SIMtrace2 sniffer device found')
 
@@ -147,6 +146,7 @@ class SniffSession:
         self._dev = dev
         self._devh = devh
         self._ep_in = ep_in
+        self._connected = True
         self._last_msg_time = time.monotonic()
         self._disconnect_count = 0
 
@@ -167,6 +167,7 @@ class SniffSession:
         self._devh = None
         self._dev = None
         self._ep_in = None
+        self._connected = False
 
     def _backoff_wait(self):
         """Sleep with exponential backoff before reconnecting."""
@@ -236,20 +237,38 @@ class SniffSession:
                 f'Inactivity timeout ({elapsed:.1f}s > '
                 f'{self._inactivity_timeout:.1f}s)')
 
+    @property
+    def connected(self):
+        """True while the USB sniffer device is open and claimed."""
+        return self._connected
+
     def iter_messages(self):
         """Generator of SniffMessage objects.
 
         Automatically reconnects on disconnect if ``reconnect=True``.
         Raises ``DeviceDisconnected`` if reconnect is disabled or exhausted.
+
+        When an established connection is lost and a reconnect is pending, a
+        single synthetic ``SniffMessage(type='gap')`` is yielded so callers can
+        record the interruption (messages may have been missed).
         """
+        from .protocol import SniffMessage
+
+        was_connected = False
         while True:
             try:
                 self._ensure_connected()
+                was_connected = True
                 yield from self._read_loop()
             except DeviceDisconnected:
                 self._close()
                 if not self._reconnect:
                     raise
+                if was_connected:
+                    yield SniffMessage(type='gap', type_hex='0x00', data=b'',
+                                       flags=0, slot_nr=0, seq_nr=0,
+                                       timestamp=time.time())
+                    was_connected = False
                 self._backoff_wait()
 
     def close(self):

simtrace2_pysniff/server/capture.py

@@ -38,6 +38,11 @@ class DirectSniffer:
         )
         self._running = False
 
+    @property
+    def connected(self):
+        """True while the USB sniffer device is open."""
+        return self._session.connected
+
     def start(self):
         self._running = True
 
@@ -81,6 +86,14 @@ class CaptureManager:
     def latest_msg_id(self):
         return self._latest_msg_id
 
+    @property
+    def device_connected(self):
+        """True while the capture device is connected, or None when the
+        backend has no device concept (gsmtap)."""
+        if isinstance(self._backend, DirectSniffer):
+            return self._backend.connected
+        return None
+
     def start_session(self):
         if self._session_id is not None:
             self.stop_session()

simtrace2_pysniff/server/database.py

@@ -257,11 +257,11 @@ class Database:
         from .decode import decode_sniff_msg
         rows = self._conn.execute(
             "SELECT data, type FROM messages WHERE session_id=? AND id < ? "
-            "AND type IN ('tpdu','atr','change') ORDER BY id DESC LIMIT 500",
+            "AND type IN ('tpdu','atr','change','gap') ORDER BY id DESC LIMIT 500",
             (session_id, before_id)).fetchall()
         states = {}
         for data, typ in reversed(rows):
-            if typ in ('atr', 'change'):
+            if typ in ('atr', 'change', 'gap'):
                 states = {}
                 continue
             channel = data[0] & 0x03 if data and len(data) >= 1 else 0
@@ -358,7 +358,22 @@ class Database:
             if msg['type'] == 'tpdu' and d and d.get('ins_hex'):
                 st['sel'], st['df'], st['sfi_map'] = self._advance_state(d, st['sel'], st['df'], st['sfi_map'])
                 st['prev'] = self._context_from_decoded(d)
-            elif msg['type'] in ('atr', 'change'):
+            elif msg['type'] == 'atr':
+                states = {}
+            elif msg['type'] == 'gap':
+                # Device disconnected and reconnected — messages may have been
+                # missed, so the selection is uncertain.
+                states = {}
+            elif msg['type'] == 'change':
+                # Only card-level changes invalidate the selection.  A
+                # waiting-time timeout interrupts a single TPDU but leaves the
+                # card selected, so the phone usually just retries.
+                from ..protocol import (
+                    CHANGE_FLAG_CARD_INSERT, CHANGE_FLAG_CARD_EJECT,
+                    CHANGE_FLAG_RESET_ASSERT, CHANGE_FLAG_RESET_DEASSERT,
+                )
+                if msg['flags'] & (CHANGE_FLAG_CARD_INSERT | CHANGE_FLAG_CARD_EJECT |
+                                   CHANGE_FLAG_RESET_ASSERT | CHANGE_FLAG_RESET_DEASSERT):
                     states = {}
             msgs.append(msg)
         return msgs

simtrace2_pysniff/server/decode.py

@@ -3258,13 +3258,28 @@ CHANGE_FLAGS = {
     1 << 4: 'Waiting time timeout',
 }
 
+# Sniff data error flags (SNIFF_DATA_FLAG_ERROR_*, simtrace_prot.h).
+DATA_FLAGS = {
+    1 << 5: 'incomplete',
+    1 << 6: 'malformed',
+    1 << 7: 'checksum error',
+    1 << 8: 'overrun',
+    1 << 9: 'framing error',
+    1 << 10: 'parity error',
+}
+
+
+def _flag_names(flags, mapping):
+    names = []
+    for mask, name in sorted(mapping.items()):
+        if flags & mask:
+            names.append(name)
+    return names
+
 
 def decode_change(flags):
     """Decode SIMtrace2 sniff_change flags into a list of human-readable names."""
-    bits = []
-    for mask, name in sorted(CHANGE_FLAGS.items()):
-        if flags & mask:
-            bits.append(name)
+    bits = _flag_names(flags, CHANGE_FLAGS)
     return {
         'type': 'change',
         'flags_hex': f'{flags:08x}',
@@ -3272,6 +3287,14 @@ def decode_change(flags):
     }
 
 
+def decode_data_flags(flags):
+    """Decode SIMtrace2 sniff_data error flags into a list of names (or None)."""
+    if not flags:
+        return None
+    names = _flag_names(flags, DATA_FLAGS)
+    return names or None
+
+
 def decode_fidi(raw_data):
     """Decode a SIMtrace2 sniff_fidi payload (1-byte Fi/Di)."""
     if len(raw_data) < 1:
@@ -3514,15 +3537,30 @@ def decode_sniff_msg(raw_data, msg_type, flags=0, prev=None):
     resolving GET RESPONSE.
     """
     if msg_type == 'tpdu' and raw_data:
-        return decode_message(raw_data, prev=prev)
+        result = decode_message(raw_data, prev=prev)
+        if result is not None:
+            errs = decode_data_flags(flags)
+            if errs:
+                result['errors'] = errs
+        return result
     if msg_type == 'change':
         return decode_change(flags)
     if msg_type == 'fidi' and raw_data:
         return decode_fidi(raw_data)
     if msg_type == 'atr':
-        return _decode_atr(raw_data)
+        result = _decode_atr(raw_data)
+        if result is not None:
+            errs = decode_data_flags(flags)
+            if errs:
+                result['errors'] = errs
+        return result
     if msg_type == 'pps':
-        return _decode_pps(raw_data)
+        result = _decode_pps(raw_data)
+        if result is not None:
+            errs = decode_data_flags(flags)
+            if errs:
+                result['errors'] = errs
+        return result
     return None
 
 

simtrace2_pysniff/server/server.py

@@ -202,6 +202,7 @@ class RequestHandler(BaseHTTPRequestHandler):
             'session_id': capture.session_id if capture else None,
             'mode': active_session['mode'] if active_session else None,
             'messages_count': self.db.count_messages(capture.session_id) if capture and capture.session_id else 0,
+            'device_connected': capture.device_connected if capture else None,
         })
 
     def _handle_list_sessions(self):
@@ -258,7 +259,8 @@ class RequestHandler(BaseHTTPRequestHandler):
     def _handle_capture_latest(self, params):
         after_id = int(params.get('after', [0])[0])
         if not self.capture or not self.capture.active:
-            self._send_json({'messages': [], 'next_after': after_id, 'active': False})
+            self._send_json({'messages': [], 'next_after': after_id, 'active': False,
+                             'device_connected': self.capture.device_connected if self.capture else None})
             return
         msg_id = self.capture.latest_msg_id
         messages = self.db.get_messages_after(self.capture.session_id, after_id)
@@ -267,12 +269,14 @@ class RequestHandler(BaseHTTPRequestHandler):
             'next_after': msg_id,
             'active': True,
             'session_id': self.capture.session_id,
+            'device_connected': self.capture.device_connected,
         })
 
     def _handle_capture_status(self):
         self._send_json({
             'active': self.capture.active if self.capture else False,
             'session_id': self.capture.session_id if self.capture else None,
+            'device_connected': self.capture.device_connected if self.capture else None,
         })
 
     def _handle_capture_start(self):

tests/test_capture.py

@@ -57,6 +57,36 @@ class TestCaptureManager(unittest.TestCase):
         sn._session = _DisconnectingSession()
         self.assertEqual(list(sn.iter_messages()), [])
 
+    def test_capture_gap_message_inserted(self):
+        # A 'gap' marker yielded by the backend is stored as a message.
+        mgr, db = self._manager(_FakeBackend([
+            ('gap', b'', 0),
+            ('tpdu', b'\x80\xf2\x00\x00\x00', 0),
+        ]))
+        sid = mgr.start_session()
+        self.assertEqual(mgr.stop_session(), sid)
+        msgs = db.get_messages(sid)
+        self.assertEqual([m['type'] for m in msgs], ['gap', 'tpdu'])
+
+    def test_direct_sniffer_connected(self):
+        from simtrace2_pysniff.server.capture import DirectSniffer
+
+        class _FakeSession:
+            connected = True
+
+        sn = DirectSniffer()
+        sn._session = _FakeSession()
+        self.assertTrue(sn.connected)
+        _FakeSession.connected = False
+        self.assertFalse(sn.connected)
+
+    def test_device_connected_gsmtap_none(self):
+        from simtrace2_pysniff.server.capture import GsmtapListener
+        listener = GsmtapListener(bind_port=0)
+        self.addCleanup(listener.stop)
+        mgr, _ = self._manager(listener)
+        self.assertIsNone(mgr.device_connected)
+
 
 if __name__ == '__main__':
     unittest.main()

tests/test_decode.py

@@ -149,6 +149,19 @@ class TestChangeAndFidiDecoding(unittest.TestCase):
         self.assertEqual(r['fi_val'], 512)
         self.assertEqual(r['di_val'], 64)
 
+    def test_tpdu_error_flags_surfaced(self):
+        r = decode_sniff_msg(bytes.fromhex('00a40000023f009000'), 'tpdu',
+                             flags=(1 << 7) | (1 << 6))
+        self.assertEqual(r['errors'], ['malformed', 'checksum error'])
+
+    def test_tpdu_no_error_flags(self):
+        r = decode_sniff_msg(bytes.fromhex('00a40000023f009000'), 'tpdu', flags=0)
+        self.assertNotIn('errors', r)
+
+    def test_atr_error_flags_surfaced(self):
+        r = decode_sniff_msg(bytes.fromhex('3b00'), 'atr', flags=(1 << 5))
+        self.assertEqual(r['errors'], ['incomplete'])
+
 
 class TestTerminalResponse(unittest.TestCase):
     def test_tr_setup_event_list(self):
@@ -1192,6 +1205,49 @@ class TestSelectionTracking(unittest.TestCase):
             msgs = db.get_messages(sid)
             self.assertNotIn('file', msgs[2]['decoded'])
 
+    def test_timeout_wt_keeps_selection(self):
+        # A waiting-time timeout interrupts one TPDU but the card stays
+        # selected, so the selection must not be reset.
+        import tempfile
+        from simtrace2_pysniff.server.database import Database
+        with tempfile.NamedTemporaryFile(suffix='.db') as tmp:
+            db = Database(tmp.name)
+            sid = db.create_session('capture')
+            db.insert_message(sid, 0.0, 'tpdu', bytes.fromhex('a0a40804047fff6f079000'))
+            db.insert_message(sid, 0.1, 'change', b'', 1 << 4)  # TIMEOUT_WT
+            db.insert_message(sid, 0.2, 'tpdu',
+                              bytes.fromhex('00b0000009') + bytes.fromhex('082905102143658709') + bytes.fromhex('9000'))
+            msgs = db.get_messages(sid)
+            self.assertEqual(msgs[2]['decoded']['file']['imsi'], '250011234567890')
+
+    def test_reset_assert_resets_selection(self):
+        import tempfile
+        from simtrace2_pysniff.server.database import Database
+        with tempfile.NamedTemporaryFile(suffix='.db') as tmp:
+            db = Database(tmp.name)
+            sid = db.create_session('capture')
+            db.insert_message(sid, 0.0, 'tpdu', bytes.fromhex('a0a40804047fff6f079000'))
+            db.insert_message(sid, 0.1, 'change', b'', 1 << 2)  # RESET_ASSERT
+            db.insert_message(sid, 0.2, 'tpdu',
+                              bytes.fromhex('00b0000009') + bytes.fromhex('082905102143658709') + bytes.fromhex('9000'))
+            msgs = db.get_messages(sid)
+            self.assertNotIn('file', msgs[2]['decoded'])
+
+    def test_gap_resets_selection(self):
+        # A capture gap (device disconnected/reconnected) means messages may
+        # have been missed, so the selection must be reset.
+        import tempfile
+        from simtrace2_pysniff.server.database import Database
+        with tempfile.NamedTemporaryFile(suffix='.db') as tmp:
+            db = Database(tmp.name)
+            sid = db.create_session('capture')
+            db.insert_message(sid, 0.0, 'tpdu', bytes.fromhex('a0a40804047fff6f079000'))
+            db.insert_message(sid, 0.1, 'gap', b'', 0)
+            db.insert_message(sid, 0.2, 'tpdu',
+                              bytes.fromhex('00b0000009') + bytes.fromhex('082905102143658709') + bytes.fromhex('9000'))
+            msgs = db.get_messages(sid)
+            self.assertNotIn('file', msgs[2]['decoded'])
+
     def test_failed_select_keeps_selection(self):
         # A SELECT that fails (6A82) must not change the current file.
         import tempfile

tests/test_pcap_import.py

@@ -208,6 +208,7 @@ class TestVersion(unittest.TestCase):
         class FakeCapture:
             active = False
             session_id = None
+            device_connected = None
 
         class Fake(RequestHandler):
             def __init__(self, db):