From 4f8131b18976d70e62f99e6b50e9d3c716e1ff31 Mon Sep 17 00:00:00 2001
From: Victoria Fischer <tdfischer@hackerbots.net>
Date: Fri, 2 Jan 2026 15:56:28 +0100
Subject: [PATCH] tasks: simulation: better handle certain errors

---
 src/simdata.rs          |  3 ++-
 src/tasks/simulation.rs | 38 ++++++++++++++++++++++++--------------
 2 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/src/simdata.rs b/src/simdata.rs
index 77e61cf..0e3e7d1 100644
--- a/src/simdata.rs
+++ b/src/simdata.rs
@@ -18,7 +18,8 @@ pub enum SimDataError<E> {
     DecodeError(E),
     EndOfStream,
     UnsupportedStreamType(ExtMeta),
-    EventHeaderMissing
+    EventHeaderMissing,
+    PartitionNotFound
 }
 
 impl<E> From<E> for SimDataError<E> {
diff --git a/src/tasks/simulation.rs b/src/tasks/simulation.rs
index 9638cb9..27f5052 100644
--- a/src/tasks/simulation.rs
+++ b/src/tasks/simulation.rs
@@ -67,7 +67,7 @@ impl<S: ReadStorage + Clone> SimDataTable<S> where S::Error: core::fmt::Debug +
         info!("Searching for sim data partition");
         let data_partition = partitions.iter().find(|partition| {
             partition.partition_type() == partition_type && partition.label_as_str() == "sim"
-        }).expect("Unable to locate 'sim' data partition!");
+        }).ok_or(SimDataError::PartitionNotFound)?;
 
         let start = data_partition.offset() as usize;
         let end = data_partition.len() as usize + start;
@@ -97,11 +97,18 @@ impl<S: ReadStorage + Clone + core::fmt::Debug> Iterator for SimDataTable<S> whe
             loop {
                 match StreamHeader::from_rmp(&mut self.reader) {
                     Ok(header) => {
-                        let sensor_reader = self.reader.subset(header.size as usize);
-                        self.reader.seek(header.size as usize);
-                        self.index += 1;
-                        debug!("Found header={header:?}");
-                        return Some(SimDataReader::open(sensor_reader, header.id));
+                        match self.reader.subset(header.size) {
+                            Ok(sensor_reader) => {
+                                self.reader.seek(header.size);
+                                self.index += 1;
+                                debug!("Found header={header:?}");
+                                return Some(SimDataReader::open(sensor_reader, header.id));
+                            },
+                            err => {
+                                error!("Read error while opening simulation stream {err:?}");
+                                return None;
+                            }
+                        }
                     },
                     Err(SimDataError::UnsupportedStreamType(meta)) => {
                         error!("Found unknown simulation data chunk {meta:?}");
@@ -109,7 +116,7 @@ impl<S: ReadStorage + Clone + core::fmt::Debug> Iterator for SimDataTable<S> whe
                         self.index += 1;
                     }
                     Err(err) => {
-                        error!("Read error while decoding simulation data {err:?}");
+                        error!("Read error while decoding simulation stream table {err:?}");
                         return None;
                     }
                 }
@@ -142,14 +149,17 @@ impl<S: ReadStorage> RangeReader<S> {
         self.offset += offset;
     }
 
-    pub fn subset(&self, size: usize) -> Self where S: Clone + core::fmt::Debug {
+    pub fn subset(&self, size: usize) -> Result<Self, SimDataError<S::Error>> where S: Clone + core::fmt::Debug {
         trace!("subset {:#02x}:{:#02x} -> {:#02x}:{:#02x}", self.start, self.end, self.start + self.offset, self.start + self.offset + size);
-        assert!(self.start + self.offset + size < self.end);
-        Self {
-            storage: self.storage.clone(),
-            start: self.offset + self.start,
-            end: self.start + self.offset + size,
-            offset: 0
+        if self.start + self.offset + size < self.end {
+            Err(SimDataError::EndOfStream)
+        } else {
+            Ok(Self {
+                storage: self.storage.clone(),
+                start: self.offset + self.start,
+                end: self.start + self.offset + size,
+                offset: 0
+            })
         }
     }
 }