Add disk space monitoring to recording lifecycle

daemon/src/config.rs

@@ -20,6 +20,20 @@ pub struct Config {
     pub ntfy_url: Option<String>,
     pub enabled_notifications: Vec<NotificationType>,
     pub analyzers: AnalyzerConfig,
+    /// Minimum disk space (MB) required to start recording
+    #[serde(default = "default_min_space_to_start_recording_mb")]
+    pub min_space_to_start_recording_mb: u64,
+    /// Minimum disk space (MB) to continue recording (stops if below this)
+    #[serde(default = "default_min_space_to_continue_recording_mb")]
+    pub min_space_to_continue_recording_mb: u64,
+}
+
+fn default_min_space_to_start_recording_mb() -> u64 {
+    1
+}
+
+fn default_min_space_to_continue_recording_mb() -> u64 {
+    1
 }
 
 impl Default for Config {
@@ -35,6 +49,8 @@ impl Default for Config {
             analyzers: AnalyzerConfig::default(),
             ntfy_url: None,
             enabled_notifications: vec![NotificationType::Warning, NotificationType::LowBattery],
+            min_space_to_start_recording_mb: default_min_space_to_start_recording_mb(),
+            min_space_to_continue_recording_mb: default_min_space_to_continue_recording_mb(),
         }
     }
 }

daemon/src/diag.rs

@@ -27,6 +27,9 @@ use crate::display;
 use crate::notifications::{Notification, NotificationType};
 use crate::qmdl_store::{RecordingStore, RecordingStoreError};
 use crate::server::ServerState;
+use crate::stats::DiskStats;
+
+const SPACE_CHECK_INTERVAL_CONTAINERS: usize = 100;
 
 pub enum DiagDeviceCtrlMessage {
     StopRecording,
@@ -46,8 +49,11 @@ pub struct DiagTask {
     analysis_sender: Sender<AnalysisCtrlMessage>,
     analyzer_config: AnalyzerConfig,
     notification_channel: tokio::sync::mpsc::Sender<Notification>,
+    min_space_to_start_mb: u64,
+    min_space_to_continue_mb: u64,
     state: DiagState,
     max_type_seen: EventType,
+    container_count: usize,
 }
 
 enum DiagState {
@@ -64,30 +70,90 @@ impl DiagTask {
         analysis_sender: Sender<AnalysisCtrlMessage>,
         analyzer_config: AnalyzerConfig,
         notification_channel: tokio::sync::mpsc::Sender<Notification>,
+        min_space_to_start_mb: u64,
+        min_space_to_continue_mb: u64,
     ) -> Self {
         Self {
             ui_update_sender,
             analysis_sender,
             analyzer_config,
             notification_channel,
+            min_space_to_start_mb,
+            min_space_to_continue_mb,
             state: DiagState::Stopped,
             max_type_seen: EventType::Informational,
+            container_count: 0,
         }
     }
 
     /// Start recording
     async fn start(&mut self, qmdl_store: &mut RecordingStore) {
         self.max_type_seen = EventType::Informational;
-        let (qmdl_file, analysis_file) = qmdl_store
+        self.container_count = 0;
-            .new_entry()
+
-            .await
+        let min_space_bytes = self.min_space_to_start_mb * 1024 * 1024;
-            .expect("failed creating QMDL file entry");
+        match DiskStats::new(qmdl_store.path.to_str().unwrap()) {
+            Ok(disk_stats) if disk_stats.available_bytes.unwrap_or(0) < min_space_bytes => {
+                let available_mb = disk_stats.available_bytes.unwrap_or(0) / 1024 / 1024;
+                error!(
+                    "Insufficient disk space to start recording: {}MB available, {}MB required",
+                    available_mb, self.min_space_to_start_mb
+                );
+
+                if let Err(e) = self
+                    .notification_channel
+                    .send(Notification::new(
+                        NotificationType::Warning,
+                        format!(
+                            "Cannot start recording: only {}MB free (need {}MB minimum)",
+                            available_mb, self.min_space_to_start_mb
+                        ),
+                        None,
+                    ))
+                    .await
+                {
+                    warn!("Failed to send notification: {e}");
+                }
+
+                if let Err(e) = self
+                    .ui_update_sender
+                    .send(display::DisplayState::Paused)
+                    .await
+                {
+                    warn!("couldn't send ui update message: {e}");
+                }
+
+                return;
+            }
+            Ok(disk_stats) => {
+                let available_mb = disk_stats.available_bytes.unwrap_or(0) / 1024 / 1024;
+                info!(
+                    "Starting recording with {}MB disk space available",
+                    available_mb
+                );
+            }
+            Err(e) => {
+                warn!("Failed to check disk space: {e}, starting recording anyway");
+            }
+        }
+
+        let (qmdl_file, analysis_file) = match qmdl_store.new_entry().await {
+            Ok(files) => files,
+            Err(e) => {
+                error!("failed creating QMDL file entry: {e}");
+                return;
+            }
+        };
         self.stop_current_recording().await;
         let qmdl_writer = QmdlWriter::new(qmdl_file);
-        let analysis_writer = AnalysisWriter::new(analysis_file, &self.analyzer_config)
+        let analysis_writer = match AnalysisWriter::new(analysis_file, &self.analyzer_config).await
-            .await
+        {
-            .map(Box::new)
+            Ok(writer) => Box::new(writer),
-            .expect("failed to write to analysis file");
+            Err(e) => {
+                error!("failed to create analysis writer: {e}");
+                return;
+            }
+        };
         self.state = DiagState::Recording {
             qmdl_writer,
             analysis_writer,
@@ -183,10 +249,60 @@ impl DiagTask {
             analysis_writer,
         } = &mut self.state
         {
-            qmdl_writer
+            self.container_count += 1;
-                .write_container(&container)
+
-                .await
+            if self.container_count % SPACE_CHECK_INTERVAL_CONTAINERS == 0 {
-                .expect("failed to write to QMDL writer");
+                let min_continue_bytes = self.min_space_to_continue_mb * 1024 * 1024;
+                let min_start_bytes = self.min_space_to_start_mb * 1024 * 1024;
+                match DiskStats::new(qmdl_store.path.to_str().unwrap()) {
+                    Ok(disk_stats)
+                        if disk_stats.available_bytes.unwrap_or(0) < min_continue_bytes =>
+                    {
+                        let available_mb = disk_stats.available_bytes.unwrap_or(0) / 1024 / 1024;
+                        error!(
+                            "Disk space critically low ({}MB), stopping recording",
+                            available_mb
+                        );
+
+                        self.notification_channel.send(Notification::new(
+                            NotificationType::Warning,
+                            format!(
+                                "Disk space critically low ({}MB), recording stopped automatically",
+                                available_mb
+                            ),
+                            None,
+                        )).await.ok();
+
+                        self.stop(qmdl_store).await;
+                        return;
+                    }
+                    Ok(disk_stats) if disk_stats.available_bytes.unwrap_or(0) < min_start_bytes => {
+                        if self.container_count % (SPACE_CHECK_INTERVAL_CONTAINERS * 10) == 0 {
+                            let available_mb =
+                                disk_stats.available_bytes.unwrap_or(0) / 1024 / 1024;
+                            warn!("Disk space low: {}MB remaining", available_mb);
+                            self.notification_channel
+                                .send(Notification::new(
+                                    NotificationType::Warning,
+                                    format!("Disk space low: {}MB free", available_mb),
+                                    Some(Duration::from_secs(30)),
+                                ))
+                                .await
+                                .ok();
+                        }
+                    }
+                    Err(e) => {
+                        warn!("Failed to check disk space: {e}");
+                    }
+                    _ => {}
+                }
+            }
+
+            if let Err(e) = qmdl_writer.write_container(&container).await {
+                error!("failed to write to QMDL (disk full?): {e}");
+                self.stop(qmdl_store).await;
+                return;
+            }
             debug!(
                 "total QMDL bytes written: {}, updating manifest...",
                 qmdl_writer.total_written
@@ -194,15 +310,22 @@ impl DiagTask {
             let index = qmdl_store
                 .current_entry
                 .expect("DiagDevice had qmdl_writer, but QmdlStore didn't have current entry???");
-            qmdl_store
+            if let Err(e) = qmdl_store
                 .update_entry_qmdl_size(index, qmdl_writer.total_written)
                 .await
-                .expect("failed to update qmdl file size");
+            {
+                error!("failed to update manifest (disk full?): {e}");
+                self.stop(qmdl_store).await;
+                return;
+            }
             debug!("done!");
-            let max_type = analysis_writer
+            let max_type = match analysis_writer.analyze(container).await {
-                .analyze(container)
+                Ok(t) => t,
-                .await
+                Err(e) => {
-                .expect("failed to analyze container");
+                    warn!("failed to analyze container: {e}");
+                    EventType::Informational
+                }
+            };
 
             if max_type > EventType::Informational {
                 info!("a heuristic triggered on this run!");
@@ -244,10 +367,12 @@ pub fn run_diag_read_thread(
     analysis_sender: Sender<AnalysisCtrlMessage>,
     analyzer_config: AnalyzerConfig,
     notification_channel: tokio::sync::mpsc::Sender<Notification>,
+    min_space_to_start_mb: u64,
+    min_space_to_continue_mb: u64,
 ) {
     task_tracker.spawn(async move {
         let mut diag_stream = pin!(dev.as_stream().into_stream());
-        let mut diag_task = DiagTask::new(ui_update_sender, analysis_sender, analyzer_config, notification_channel);
+        let mut diag_task = DiagTask::new(ui_update_sender, analysis_sender, analyzer_config, notification_channel, min_space_to_start_mb, min_space_to_continue_mb);
         qmdl_file_tx
             .send(DiagDeviceCtrlMessage::StartRecording)
             .await

daemon/src/main.rs

@@ -234,6 +234,8 @@ async fn run_with_config(
             analysis_tx.clone(),
             config.analyzers.clone(),
             notification_service.new_handler(),
+            config.min_space_to_start_recording_mb,
+            config.min_space_to_continue_recording_mb,
         );
         info!("Starting UI");
 

daemon/src/stats.rs

@@ -1,3 +1,4 @@
+use std::ffi::CString;
 use std::sync::Arc;
 
 use crate::battery::get_battery_status;
@@ -25,7 +26,7 @@ pub struct SystemStats {
 impl SystemStats {
     pub async fn new(qmdl_path: &str, device: &Device) -> Result<Self, String> {
         Ok(Self {
-            disk_stats: DiskStats::new(qmdl_path, device).await?,
+            disk_stats: DiskStats::new(qmdl_path)?,
             memory_stats: MemoryStats::new(device).await?,
             runtime_metadata: RuntimeMetadata::new(),
             battery_status: match get_battery_status(device).await {
@@ -48,33 +49,42 @@ pub struct DiskStats {
     available_size: String,
     used_percent: String,
     mounted_on: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub available_bytes: Option<u64>,
 }
 
 impl DiskStats {
-    // runs "df -h <qmdl_path>" to get storage statistics for the partition containing
+    #[allow(clippy::unnecessary_cast)] // c_ulong is u32 on ARM, u64 on macOS
-    // the QMDL file.
+    pub fn new(qmdl_path: &str) -> Result<Self, String> {
-    pub async fn new(qmdl_path: &str, device: &Device) -> Result<Self, String> {
+        let c_path =
-        // Uz801 needs to be told to use the busybox df specifically
+            CString::new(qmdl_path).map_err(|e| format!("invalid path {qmdl_path}: {e}"))?;
-        let mut df_cmd: Command;
+        let mut stat: libc::statvfs = unsafe { std::mem::zeroed() };
-        if matches!(device, Device::Uz801) {
+        if unsafe { libc::statvfs(c_path.as_ptr(), &mut stat) } != 0 {
-            df_cmd = Command::new("busybox");
+            return Err(format!(
-            df_cmd.arg("df");
+                "statvfs({qmdl_path}) failed: {}",
-        } else {
+                std::io::Error::last_os_error()
-            df_cmd = Command::new("df");
+            ));
         }
-        df_cmd.arg("-h");
-        df_cmd.arg(qmdl_path);
-        let stdout = get_cmd_output(df_cmd).await?;
 
-        // Handle standard df -h format
+        let block_size = stat.f_frsize as u64;
-        let mut parts = stdout.split_whitespace().skip(7);
+        let total_kb = (stat.f_blocks as u64 * block_size / 1024) as usize;
+        let free_kb = (stat.f_bfree as u64 * block_size / 1024) as usize;
+        let available_kb = (stat.f_bavail as u64 * block_size / 1024) as usize;
+        let used_kb = total_kb.saturating_sub(free_kb);
+        let used_percent = if stat.f_blocks > 0 {
+            format!("{}%", (stat.f_blocks - stat.f_bfree) * 100 / stat.f_blocks)
+        } else {
+            "0%".to_string()
+        };
+
         Ok(Self {
-            partition: parts.next().ok_or("error parsing df output")?.to_string(),
+            partition: qmdl_path.to_string(),
-            total_size: parts.next().ok_or("error parsing df output")?.to_string(),
+            total_size: humanize_kb(total_kb),
-            used_size: parts.next().ok_or("error parsing df output")?.to_string(),
+            used_size: humanize_kb(used_kb),
-            available_size: parts.next().ok_or("error parsing df output")?.to_string(),
+            available_size: humanize_kb(available_kb),
-            used_percent: parts.next().ok_or("error parsing df output")?.to_string(),
+            used_percent,
-            mounted_on: parts.next().ok_or("error parsing df output")?.to_string(),
+            mounted_on: qmdl_path.to_string(),
+            available_bytes: Some(stat.f_bavail as u64 * block_size),
         })
     }
 }

daemon/web/src/lib/components/ConfigForm.svelte

@@ -241,6 +241,48 @@
                     </div>
                 </div>
 
+                <div class="border-t pt-4 mt-6 space-y-3">
+                    <h3 class="text-lg font-semibold text-gray-800 mb-4">Storage Management</h3>
+
+                    <div>
+                        <label
+                            for="min_space_to_start_recording_mb"
+                            class="block text-sm font-medium text-gray-700 mb-1"
+                        >
+                            Minimum Space to Start Recording (MB)
+                        </label>
+                        <input
+                            id="min_space_to_start_recording_mb"
+                            type="number"
+                            min="1"
+                            bind:value={config.min_space_to_start_recording_mb}
+                            class="w-full px-3 py-2 border border-gray-300 rounded-md focus:outline-none focus:ring-2 focus:ring-rayhunter-blue"
+                        />
+                        <p class="text-xs text-gray-500 mt-1">
+                            Recording will not start if less than this amount of disk space is free
+                        </p>
+                    </div>
+
+                    <div>
+                        <label
+                            for="min_space_to_continue_recording_mb"
+                            class="block text-sm font-medium text-gray-700 mb-1"
+                        >
+                            Minimum Space to Continue Recording (MB)
+                        </label>
+                        <input
+                            id="min_space_to_continue_recording_mb"
+                            type="number"
+                            min="1"
+                            bind:value={config.min_space_to_continue_recording_mb}
+                            class="w-full px-3 py-2 border border-gray-300 rounded-md focus:outline-none focus:ring-2 focus:ring-rayhunter-blue"
+                        />
+                        <p class="text-xs text-gray-500 mt-1">
+                            Recording will stop automatically if disk space drops below this level
+                        </p>
+                    </div>
+                </div>
+
                 <div class="border-t pt-4 mt-6">
                     <h3 class="text-lg font-semibold text-gray-800 mb-4">
                         Analyzer Heuristic Settings

daemon/web/src/lib/utils.svelte.ts

@@ -25,6 +25,8 @@ export interface Config {
     ntfy_url: string;
     enabled_notifications: enabled_notifications[];
     analyzers: AnalyzerConfig;
+    min_space_to_start_recording_mb: number;
+    min_space_to_continue_recording_mb: number;
 }
 
 export async function req(method: string, url: string, json_body?: unknown): Promise<string> {

dist/config.toml.in

@@ -28,6 +28,12 @@ ntfy_url = ""
 # What notification types to enable. Does nothing if the above ntfy_url is not set.
 enabled_notifications = ["Warning", "LowBattery"]
 
+# Disk Space Management
+# Minimum free space (MB) required to start recording
+min_space_to_start_recording_mb = 1
+# Minimum free space (MB) to continue recording (stops if below this)
+min_space_to_continue_recording_mb = 1
+
 # Analyzer Configuration
 # Enable/disable specific IMSI catcher detection heuristics
 # See https://github.com/EFForg/rayhunter/blob/main/doc/heuristics.md for details