Merge pull request 'satrs-core v0.1.0-alpha.3' (#108) from core-v0.1.0-alpha.3 into main

Reviewed-on: #108

satrs-book/README.md

@@ -5,7 +5,14 @@ High-level documentation of the [sat-rs project](https://absatsw.irs.uni-stuttga
 
 ## Building
 
-If you have not done so, install `mdbook` using `cargo install mdbook --locked`.
+If you have not done so, install the pre-requisites first:
+
+```sh
+cargo install mdbook --locked
+cargo install mdbook-linkcheck --locked
+```
+
+After that, you can build the book with:
 
 ```sh
 mdbook build

satrs-book/src/constrained-systems.md

@@ -11,7 +11,8 @@ time where the OBSW might be running on Linux based systems with hundreds of MBs
 
 A useful pattern used commonly in space systems is to limit heap allocations to program
 initialization time and avoid frequent run-time allocations. This prevents issues like
-running out of memory (something even Rust can not protect from) or heap fragmentation.
+running out of memory (something even Rust can not protect from) or heap fragmentation on systems
+without a MMU.
 
 # Using pre-allocated pool structures
 
@@ -24,6 +25,12 @@ For example, a very small telecommand (TC) pool might look like this:
 
 ![Example Pool](images/pools/static-pools.png)
 
+The core of the pool abstractions is the
+[PoolProvider trait](https://docs.rs/satrs-core/0.1.0-alpha.3/satrs_core/pool/trait.PoolProvider.html).
+This trait specifies the general API a pool structure should have without making assumption
+of how the data is stored.
+
+This trait is implemented by a static memory pool implementation.
 The code to generate this static pool would look like this:
 
 ```rust
@@ -39,21 +46,27 @@ let tc_pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![
 
 It should be noted that the buckets only show the maximum size of data being stored inside them.
 The store will keep a separate structure to track the actual size of the data being stored.
-
-<!-- TODO: Add explanation and references for used data-structures. Also explain core trait
-to work with the pool. -->
-
 A TC entry inside this pool has a store address which can then be sent around without having
 to dynamically allocate memory. The same principle can also be applied to the telemetry (TM) and
 inter-process communication (IPC) data.
 
+You can read
+
+- [`StaticPoolConfig` API](https://docs.rs/satrs-core/0.1.0-alpha.3/satrs_core/pool/struct.StaticPoolConfig.html)
+- [`StaticMemoryPool` API](https://docs.rs/satrs-core/0.1.0-alpha.3/satrs_core/pool/struct.StaticMemoryPool.html)
+
+for more details.
+
+In the future, optimized pool structures which use standard containers or are
+[`Sync`](https://doc.rust-lang.org/std/marker/trait.Sync.html) by default might be added as well.
+
 # Using special crates to prevent smaller allocations
 
 Another common way to use the heap on host systems is using containers like `String` and `Vec<u8>`
 to work with data where the size is not known beforehand. The most common solution for embedded
 systems is to determine the maximum expected size and then use a pre-allocated `u8` buffer and a
 size variable. Alternatively, you can use the following crates for more convenience or a smart
-behaviour which at the very least reduce heap allocations:
+behaviour which at the very least reduces heap allocations:
 
 1. [`smallvec`](https://docs.rs/smallvec/latest/smallvec/).
 2. [`arrayvec`](https://docs.rs/arrayvec/latest/arrayvec/index.html) which also contains an

satrs-core/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "satrs-core"
-version = "0.1.0-alpha.2"
+version = "0.1.0-alpha.3"
 edition = "2021"
 rust-version = "1.61"
 authors = ["Robin Mueller <muellerr@irs.uni-stuttgart.de>"]

satrs-core/src/pool.rs

@@ -1,13 +1,21 @@
 //! # Pool implementation providing memory pools for packet storage.
 //!
+//! This module provides generic abstractions for memory pools which provide a storage
+//! machanism for variable sized data like Telemetry and Telecommand (TMTC) packets. The core
+//! abstraction for this is the [PoolProvider] trait.
+//!
+//! It also contains the [StaticMemoryPool] as a concrete implementation which can be used to avoid
+//! dynamic run-time allocations for the storage of TMTC packets.
+//!
 //! # Example for the [StaticMemoryPool]
 //!
 //! ```
-//! use satrs_core::pool::{PoolProviderMemInPlace, StaticMemoryPool, StaticPoolConfig};
+//! use satrs_core::pool::{PoolProvider, StaticMemoryPool, StaticPoolConfig};
 //!
 //! // 4 buckets of 4 bytes, 2 of 8 bytes and 1 of 16 bytes
-//! let pool_cfg = StaticPoolConfig::new(vec![(4, 4), (2, 8), (1, 16)]);
+//! let pool_cfg = StaticPoolConfig::new(vec![(4, 4), (2, 8), (1, 16)], false);
 //! let mut local_pool = StaticMemoryPool::new(pool_cfg);
+//! let mut read_buf: [u8; 16] = [0; 16];
 //! let mut addr;
 //! {
 //!     // Add new data to the pool
@@ -20,25 +28,25 @@
 //!
 //! {
 //!     // Read the store data back
-//!     let res = local_pool.read(&addr);
+//!     let res = local_pool.read(&addr, &mut read_buf);
 //!     assert!(res.is_ok());
-//!     let buf_read_back = res.unwrap();
-//!     assert_eq!(buf_read_back.len(), 4);
-//!     assert_eq!(buf_read_back[0], 42);
+//!     let read_bytes = res.unwrap();
+//!     assert_eq!(read_bytes, 4);
+//!     assert_eq!(read_buf[0], 42);
 //!     // Modify the stored data
-//!     let res = local_pool.modify(&addr);
+//!     let res = local_pool.modify(&addr, |buf| {
+//!         buf[0] = 12;
+//!     });
 //!     assert!(res.is_ok());
-//!     let buf_read_back = res.unwrap();
-//!     buf_read_back[0] = 12;
 //! }
 //!
 //! {
 //!     // Read the modified data back
-//!     let res = local_pool.read(&addr);
+//!     let res = local_pool.read(&addr, &mut read_buf);
 //!     assert!(res.is_ok());
-//!     let buf_read_back = res.unwrap();
-//!     assert_eq!(buf_read_back.len(), 4);
-//!     assert_eq!(buf_read_back[0], 12);
+//!     let read_bytes = res.unwrap();
+//!     assert_eq!(read_bytes, 4);
+//!     assert_eq!(read_buf[0], 12);
 //! }
 //!
 //! // Delete the stored data
@@ -46,21 +54,21 @@
 //!
 //! // Get a free element in the pool with an appropriate size
 //! {
-//!     let res = local_pool.free_element(12);
+//!     let res = local_pool.free_element(12, |buf| {
+//!         buf[0] = 7;
+//!     });
 //!     assert!(res.is_ok());
-//!     let (tmp, mut_buf) = res.unwrap();
-//!     addr = tmp;
-//!     mut_buf[0] = 7;
+//!     addr = res.unwrap();
 //! }
 //!
 //! // Read back the data
 //! {
 //!     // Read the store data back
-//!     let res = local_pool.read(&addr);
+//!     let res = local_pool.read(&addr, &mut read_buf);
 //!     assert!(res.is_ok());
-//!     let buf_read_back = res.unwrap();
-//!     assert_eq!(buf_read_back.len(), 12);
-//!     assert_eq!(buf_read_back[0], 7);
+//!     let read_bytes = res.unwrap();
+//!     assert_eq!(read_bytes, 12);
+//!     assert_eq!(read_buf[0], 7);
 //! }
 //! ```
 #[cfg(feature = "alloc")]
@@ -70,6 +78,7 @@ use core::fmt::{Display, Formatter};
 use delegate::delegate;
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
+use spacepackets::ByteConversionError;
 #[cfg(feature = "std")]
 use std::error::Error;
 
@@ -151,6 +160,8 @@ pub enum StoreError {
     InvalidStoreId(StoreIdError, Option<StoreAddr>),
     /// Valid subpool and packet index, but no data is stored at the given address
     DataDoesNotExist(StoreAddr),
+    ByteConversionError(spacepackets::ByteConversionError),
+    LockError,
     /// Internal or configuration errors
     InternalError(u32),
 }
@@ -173,10 +184,22 @@ impl Display for StoreError {
             StoreError::InternalError(e) => {
                 write!(f, "internal error: {e}")
             }
+            StoreError::ByteConversionError(e) => {
+                write!(f, "store error: {e}")
+            }
+            StoreError::LockError => {
+                write!(f, "lock error")
+            }
         }
     }
 }
 
+impl From<ByteConversionError> for StoreError {
+    fn from(value: ByteConversionError) -> Self {
+        Self::ByteConversionError(value)
+    }
+}
+
 #[cfg(feature = "std")]
 impl Error for StoreError {
     fn source(&self) -> Option<&(dyn Error + 'static)> {
@@ -187,41 +210,61 @@ impl Error for StoreError {
     }
 }
 
-/// Generic trait for pool providers where the data can be modified and read in-place. This
-/// generally means that a shared pool structure has to be wrapped inside a lock structure.
-pub trait PoolProviderMemInPlace {
+/// Generic trait for pool providers which provide memory pools for variable sized data.
+///
+/// It specifies a basic API to [Self::add], [Self::modify], [Self::read] and [Self::delete] data
+/// in the store at its core. The API was designed so internal optimizations can be performed
+/// more easily and that is is also possible to make the pool structure [Sync] without the whole
+/// pool structure being wrapped inside a lock.
+pub trait PoolProvider {
     /// Add new data to the pool. The provider should attempt to reserve a memory block with the
     /// appropriate size and then copy the given data to the block. Yields a [StoreAddr] which can
     /// be used to access the data stored in the pool
     fn add(&mut self, data: &[u8]) -> Result<StoreAddr, StoreError>;
 
-    /// The provider should attempt to reserve a free memory block with the appropriate size and
-    /// then return a mutable reference to it. Yields a [StoreAddr] which can be used to access
-    /// the data stored in the pool
-    fn free_element(&mut self, len: usize) -> Result<(StoreAddr, &mut [u8]), StoreError>;
+    /// The provider should attempt to reserve a free memory block with the appropriate size first.
+    /// It then executes a user-provided closure and passes a mutable reference to that memory
+    /// block to the closure. This allows the user to write data to the memory block.
+    /// The function should yield a [StoreAddr] which can be used to access the data stored in the
+    /// pool.
+    fn free_element<W: FnMut(&mut [u8])>(
+        &mut self,
+        len: usize,
+        writer: W,
+    ) -> Result<StoreAddr, StoreError>;
 
-    /// Modify data added previously using a given [StoreAddr] by yielding a mutable reference
-    /// to it
-    fn modify(&mut self, addr: &StoreAddr) -> Result<&mut [u8], StoreError>;
+    /// Modify data added previously using a given [StoreAddr]. The provider should use the store
+    /// address to determine if a memory block exists for that address. If it does, it should
+    /// call the user-provided closure and pass a mutable reference to the memory block
+    /// to the closure. This allows the user to modify the memory block.
+    fn modify<U: FnMut(&mut [u8])>(
+        &mut self,
+        addr: &StoreAddr,
+        updater: U,
+    ) -> Result<(), StoreError>;
 
-    /// Read data by yielding a read-only reference given a [StoreAddr]
-    fn read(&self, addr: &StoreAddr) -> Result<&[u8], StoreError>;
+    /// The provider should copy the data from the memory block to the user-provided buffer if
+    /// it exists.
+    fn read(&self, addr: &StoreAddr, buf: &mut [u8]) -> Result<usize, StoreError>;
 
-    /// Delete data inside the pool given a [StoreAddr]
+    /// Delete data inside the pool given a [StoreAddr].
     fn delete(&mut self, addr: StoreAddr) -> Result<(), StoreError>;
     fn has_element_at(&self, addr: &StoreAddr) -> Result<bool, StoreError>;
 
     /// Retrieve the length of the data at the given store address.
-    fn len_of_data(&self, addr: &StoreAddr) -> Result<usize, StoreError> {
-        if !self.has_element_at(addr)? {
-            return Err(StoreError::DataDoesNotExist(*addr));
-        }
-        Ok(self.read(addr)?.len())
+    fn len_of_data(&self, addr: &StoreAddr) -> Result<usize, StoreError>;
+
+    #[cfg(feature = "alloc")]
+    fn read_as_vec(&self, addr: &StoreAddr) -> Result<alloc::vec::Vec<u8>, StoreError> {
+        let mut vec = alloc::vec![0; self.len_of_data(addr)?];
+        self.read(addr, &mut vec)?;
+        Ok(vec)
     }
 }
 
-pub trait PoolProviderMemInPlaceWithGuards: PoolProviderMemInPlace {
-    /// This function behaves like [PoolProviderMemInPlace::read], but consumes the provided address
+/// Extension trait which adds guarded pool access classes.
+pub trait PoolProviderWithGuards: PoolProvider {
+    /// This function behaves like [PoolProvider::read], but consumes the provided address
     /// and returns a RAII conformant guard object.
     ///
     /// Unless the guard [PoolRwGuard::release] method is called, the data for the
@@ -231,7 +274,7 @@ pub trait PoolProviderMemInPlaceWithGuards: PoolProviderMemInPlace {
     /// manual deletion is necessary when returning from a processing function prematurely.
     fn read_with_guard(&mut self, addr: StoreAddr) -> PoolGuard<Self>;
 
-    /// This function behaves like [PoolProviderMemInPlace::modify], but consumes the provided
+    /// This function behaves like [PoolProvider::modify], but consumes the provided
     /// address and returns a RAII conformant guard object.
     ///
     /// Unless the guard [PoolRwGuard::release] method is called, the data for the
@@ -242,15 +285,16 @@ pub trait PoolProviderMemInPlaceWithGuards: PoolProviderMemInPlace {
     fn modify_with_guard(&mut self, addr: StoreAddr) -> PoolRwGuard<Self>;
 }
 
-pub struct PoolGuard<'a, MemProvider: PoolProviderMemInPlace + ?Sized> {
+pub struct PoolGuard<'a, MemProvider: PoolProvider + ?Sized> {
     pool: &'a mut MemProvider,
     pub addr: StoreAddr,
     no_deletion: bool,
     deletion_failed_error: Option<StoreError>,
 }
 
-/// This helper object
-impl<'a, MemProvider: PoolProviderMemInPlace> PoolGuard<'a, MemProvider> {
+/// This helper object can be used to safely access pool data without worrying about memory
+/// leaks.
+impl<'a, MemProvider: PoolProvider> PoolGuard<'a, MemProvider> {
     pub fn new(pool: &'a mut MemProvider, addr: StoreAddr) -> Self {
         Self {
             pool,
@@ -260,8 +304,13 @@ impl<'a, MemProvider: PoolProviderMemInPlace> PoolGuard<'a, MemProvider> {
         }
     }
 
-    pub fn read(&self) -> Result<&[u8], StoreError> {
-        self.pool.read(&self.addr)
+    pub fn read(&self, buf: &mut [u8]) -> Result<usize, StoreError> {
+        self.pool.read(&self.addr, buf)
+    }
+
+    #[cfg(feature = "alloc")]
+    pub fn read_as_vec(&self) -> Result<alloc::vec::Vec<u8>, StoreError> {
+        self.pool.read_as_vec(&self.addr)
     }
 
     /// Releasing the pool guard will disable the automatic deletion of the data when the guard
@@ -271,7 +320,7 @@ impl<'a, MemProvider: PoolProviderMemInPlace> PoolGuard<'a, MemProvider> {
     }
 }
 
-impl<MemProvider: PoolProviderMemInPlace + ?Sized> Drop for PoolGuard<'_, MemProvider> {
+impl<MemProvider: PoolProvider + ?Sized> Drop for PoolGuard<'_, MemProvider> {
     fn drop(&mut self) {
         if !self.no_deletion {
             if let Err(e) = self.pool.delete(self.addr) {
@@ -281,24 +330,24 @@ impl<MemProvider: PoolProviderMemInPlace + ?Sized> Drop for PoolGuard<'_, MemPro
     }
 }
 
-pub struct PoolRwGuard<'a, MemProvider: PoolProviderMemInPlace + ?Sized> {
+pub struct PoolRwGuard<'a, MemProvider: PoolProvider + ?Sized> {
     guard: PoolGuard<'a, MemProvider>,
 }
 
-impl<'a, MemProvider: PoolProviderMemInPlace> PoolRwGuard<'a, MemProvider> {
+impl<'a, MemProvider: PoolProvider> PoolRwGuard<'a, MemProvider> {
     pub fn new(pool: &'a mut MemProvider, addr: StoreAddr) -> Self {
         Self {
             guard: PoolGuard::new(pool, addr),
         }
     }
 
-    pub fn modify(&mut self) -> Result<&mut [u8], StoreError> {
-        self.guard.pool.modify(&self.guard.addr)
+    pub fn update<U: FnMut(&mut [u8])>(&mut self, updater: &mut U) -> Result<(), StoreError> {
+        self.guard.pool.modify(&self.guard.addr, updater)
     }
 
     delegate!(
         to self.guard {
-            pub fn read(&self) -> Result<&[u8], StoreError>;
+            pub fn read(&self, buf: &mut [u8]) -> Result<usize, StoreError>;
             /// Releasing the pool guard will disable the automatic deletion of the data when the guard
             /// is dropped.
             pub fn release(&mut self);
@@ -308,13 +357,11 @@ impl<'a, MemProvider: PoolProviderMemInPlace> PoolRwGuard<'a, MemProvider> {
 
 #[cfg(feature = "alloc")]
 mod alloc_mod {
-    use super::{
-        PoolGuard, PoolProviderMemInPlace, PoolProviderMemInPlaceWithGuards, PoolRwGuard,
-        StaticPoolAddr,
-    };
+    use super::{PoolGuard, PoolProvider, PoolProviderWithGuards, PoolRwGuard, StaticPoolAddr};
     use crate::pool::{NumBlocks, StoreAddr, StoreError, StoreIdError};
     use alloc::vec;
     use alloc::vec::Vec;
+    use spacepackets::ByteConversionError;
     #[cfg(feature = "std")]
     use std::sync::{Arc, RwLock};
 
@@ -329,16 +376,24 @@ mod alloc_mod {
     ///
     /// # Parameters
     ///
-    /// * `cfg`: Vector of tuples which represent a subpool. The first entry in the tuple specifies the
-    ///       number of memory blocks in the subpool, the second entry the size of the blocks
+    /// * `cfg` - Vector of tuples which represent a subpool. The first entry in the tuple specifies
+    ///     the number of memory blocks in the subpool, the second entry the size of the blocks
+    /// * `spill_to_higher_subpools` - Specifies whether data will be spilled to higher subpools
+    ///     if the next fitting subpool is full. This is useful to ensure the pool remains useful
+    ///     for all data sizes as long as possible. However, an undesirable side-effect might be
+    ///     the chocking of larger subpools by underdimensioned smaller subpools.
     #[derive(Clone)]
     pub struct StaticPoolConfig {
         cfg: Vec<(NumBlocks, usize)>,
+        spill_to_higher_subpools: bool,
     }
 
     impl StaticPoolConfig {
-        pub fn new(cfg: Vec<(NumBlocks, usize)>) -> Self {
-            StaticPoolConfig { cfg }
+        pub fn new(cfg: Vec<(NumBlocks, usize)>, spill_to_higher_subpools: bool) -> Self {
+            StaticPoolConfig {
+                cfg,
+                spill_to_higher_subpools,
+            }
         }
 
         pub fn cfg(&self) -> &Vec<(NumBlocks, usize)> {
@@ -356,16 +411,21 @@ mod alloc_mod {
 
     /// Pool implementation providing sub-pools with fixed size memory blocks.
     ///
-    /// This is a simple memory pool implementation which pre-allocates all sub-pools using a given pool
-    /// configuration. After the pre-allocation, no dynamic memory allocation will be performed
-    /// during run-time. This makes the implementation suitable for real-time applications and
-    /// embedded environments. The pool implementation will also track the size of the data stored
-    /// inside it.
+    /// This is a simple memory pool implementation which pre-allocates all subpools using a given
+    /// pool configuration. After the pre-allocation, no dynamic memory allocation will be
+    /// performed during run-time. This makes the implementation suitable for real-time
+    /// applications and embedded environments.
+    ///
+    /// The subpool bucket sizes only denote the maximum possible data size being stored inside
+    /// them and the pool implementation will still track the size of the data stored inside it.
+    /// The implementation will generally determine the best fitting subpool for given data to
+    /// add. Currently, the pool does not support spilling to larger subpools if the closest
+    /// fitting subpool is full. This might be added in the future.
     ///
     /// Transactions with the [pool][StaticMemoryPool] are done using a generic
-    /// [address][StoreAddr] type.
-    /// Adding any data to the pool will yield a store address. Modification and read operations are
-    /// done using a reference to a store address. Deletion will consume the store address.
+    /// [address][StoreAddr] type. Adding any data to the pool will yield a store address.
+    /// Modification and read operations are done using a reference to a store address. Deletion
+    /// will consume the store address.
     pub struct StaticMemoryPool {
         pool_cfg: StaticPoolConfig,
         pool: Vec<Vec<u8>>,
@@ -422,7 +482,17 @@ mod alloc_mod {
         }
 
         fn reserve(&mut self, data_len: usize) -> Result<StaticPoolAddr, StoreError> {
-            let subpool_idx = self.find_subpool(data_len, 0)?;
+            let mut subpool_idx = self.find_subpool(data_len, 0)?;
+
+            if self.pool_cfg.spill_to_higher_subpools {
+                while let Err(StoreError::StoreFull(_)) = self.find_empty(subpool_idx) {
+                    if (subpool_idx + 1) as usize == self.sizes_lists.len() {
+                        return Err(StoreError::StoreFull(subpool_idx));
+                    }
+                    subpool_idx += 1;
+                }
+            }
+
             let (slot, size_slot_ref) = self.find_empty(subpool_idx)?;
             *size_slot_ref = data_len;
             Ok(StaticPoolAddr {
@@ -476,7 +546,7 @@ mod alloc_mod {
         }
     }
 
-    impl PoolProviderMemInPlace for StaticMemoryPool {
+    impl PoolProvider for StaticMemoryPool {
         fn add(&mut self, data: &[u8]) -> Result<StoreAddr, StoreError> {
             let data_len = data.len();
             if data_len > POOL_MAX_SIZE {
@@ -487,7 +557,11 @@ mod alloc_mod {
             Ok(addr.into())
         }
 
-        fn free_element(&mut self, len: usize) -> Result<(StoreAddr, &mut [u8]), StoreError> {
+        fn free_element<W: FnMut(&mut [u8])>(
+            &mut self,
+            len: usize,
+            mut writer: W,
+        ) -> Result<StoreAddr, StoreError> {
             if len > POOL_MAX_SIZE {
                 return Err(StoreError::DataTooLarge(len));
             }
@@ -495,25 +569,40 @@ mod alloc_mod {
             let raw_pos = self.raw_pos(&addr).unwrap();
             let block =
                 &mut self.pool.get_mut(addr.pool_idx as usize).unwrap()[raw_pos..raw_pos + len];
-            Ok((addr.into(), block))
+            writer(block);
+            Ok(addr.into())
         }
 
-        fn modify(&mut self, addr: &StoreAddr) -> Result<&mut [u8], StoreError> {
+        fn modify<U: FnMut(&mut [u8])>(
+            &mut self,
+            addr: &StoreAddr,
+            mut updater: U,
+        ) -> Result<(), StoreError> {
             let addr = StaticPoolAddr::from(*addr);
             let curr_size = self.addr_check(&addr)?;
             let raw_pos = self.raw_pos(&addr).unwrap();
             let block = &mut self.pool.get_mut(addr.pool_idx as usize).unwrap()
                 [raw_pos..raw_pos + curr_size];
-            Ok(block)
+            updater(block);
+            Ok(())
         }
 
-        fn read(&self, addr: &StoreAddr) -> Result<&[u8], StoreError> {
+        fn read(&self, addr: &StoreAddr, buf: &mut [u8]) -> Result<usize, StoreError> {
             let addr = StaticPoolAddr::from(*addr);
             let curr_size = self.addr_check(&addr)?;
+            if buf.len() < curr_size {
+                return Err(ByteConversionError::ToSliceTooSmall {
+                    found: buf.len(),
+                    expected: curr_size,
+                }
+                .into());
+            }
             let raw_pos = self.raw_pos(&addr).unwrap();
             let block =
                 &self.pool.get(addr.pool_idx as usize).unwrap()[raw_pos..raw_pos + curr_size];
-            Ok(block)
+            //block.copy_from_slice(&src);
+            buf[..curr_size].copy_from_slice(block);
+            Ok(curr_size)
         }
 
         fn delete(&mut self, addr: StoreAddr) -> Result<(), StoreError> {
@@ -540,9 +629,21 @@ mod alloc_mod {
             }
             Ok(true)
         }
+
+        fn len_of_data(&self, addr: &StoreAddr) -> Result<usize, StoreError> {
+            let addr = StaticPoolAddr::from(*addr);
+            self.validate_addr(&addr)?;
+            let pool_idx = addr.pool_idx as usize;
+            let size_list = self.sizes_lists.get(pool_idx).unwrap();
+            let size = size_list[addr.packet_idx as usize];
+            Ok(match size {
+                STORE_FREE => 0,
+                _ => size,
+            })
+        }
     }
 
-    impl PoolProviderMemInPlaceWithGuards for StaticMemoryPool {
+    impl PoolProviderWithGuards for StaticMemoryPool {
         fn modify_with_guard(&mut self, addr: StoreAddr) -> PoolRwGuard<Self> {
             PoolRwGuard::new(self, addr)
         }
@@ -556,30 +657,29 @@ mod alloc_mod {
 #[cfg(test)]
 mod tests {
     use crate::pool::{
-        PoolGuard, PoolProviderMemInPlace, PoolProviderMemInPlaceWithGuards, PoolRwGuard,
-        StaticMemoryPool, StaticPoolAddr, StaticPoolConfig, StoreError, StoreIdError,
-        POOL_MAX_SIZE,
+        PoolGuard, PoolProvider, PoolProviderWithGuards, PoolRwGuard, StaticMemoryPool,
+        StaticPoolAddr, StaticPoolConfig, StoreError, StoreIdError, POOL_MAX_SIZE,
     };
     use std::vec;
 
     fn basic_small_pool() -> StaticMemoryPool {
         // 4 buckets of 4 bytes, 2 of 8 bytes and 1 of 16 bytes
-        let pool_cfg = StaticPoolConfig::new(vec![(4, 4), (2, 8), (1, 16)]);
+        let pool_cfg = StaticPoolConfig::new(vec![(4, 4), (2, 8), (1, 16)], false);
         StaticMemoryPool::new(pool_cfg)
     }
 
     #[test]
     fn test_cfg() {
         // Values where number of buckets is 0 or size is too large should be removed
-        let mut pool_cfg = StaticPoolConfig::new(vec![(0, 0), (1, 0), (2, POOL_MAX_SIZE)]);
+        let mut pool_cfg = StaticPoolConfig::new(vec![(0, 0), (1, 0), (2, POOL_MAX_SIZE)], false);
         pool_cfg.sanitize();
         assert_eq!(*pool_cfg.cfg(), vec![(1, 0)]);
         // Entries should be ordered according to bucket size
-        pool_cfg = StaticPoolConfig::new(vec![(16, 6), (32, 3), (8, 12)]);
+        pool_cfg = StaticPoolConfig::new(vec![(16, 6), (32, 3), (8, 12)], false);
         pool_cfg.sanitize();
         assert_eq!(*pool_cfg.cfg(), vec![(32, 3), (16, 6), (8, 12)]);
         // Unstable sort is used, so order of entries with same block length should not matter
-        pool_cfg = StaticPoolConfig::new(vec![(12, 12), (14, 16), (10, 12)]);
+        pool_cfg = StaticPoolConfig::new(vec![(12, 12), (14, 16), (10, 12)], false);
         pool_cfg.sanitize();
         assert!(
             *pool_cfg.cfg() == vec![(12, 12), (10, 12), (14, 16)]
@@ -594,13 +694,14 @@ mod tests {
         for (i, val) in test_buf.iter_mut().enumerate() {
             *val = i as u8;
         }
+        let mut other_buf: [u8; 16] = [0; 16];
         let addr = local_pool.add(&test_buf).expect("Adding data failed");
         // Read back data and verify correctness
-        let res = local_pool.read(&addr);
+        let res = local_pool.read(&addr, &mut other_buf);
         assert!(res.is_ok());
-        let buf_read_back = res.unwrap();
-        assert_eq!(buf_read_back.len(), 16);
-        for (i, &val) in buf_read_back.iter().enumerate() {
+        let read_len = res.unwrap();
+        assert_eq!(read_len, 16);
+        for (i, &val) in other_buf.iter().enumerate() {
             assert_eq!(val, i as u8);
         }
     }
@@ -610,8 +711,10 @@ mod tests {
         let mut local_pool = basic_small_pool();
         let test_buf: [u8; 12] = [0; 12];
         let addr = local_pool.add(&test_buf).expect("Adding data failed");
-        let res = local_pool.read(&addr).expect("Read back failed");
-        assert_eq!(res.len(), 12);
+        let res = local_pool
+            .read(&addr, &mut [0; 12])
+            .expect("Read back failed");
+        assert_eq!(res, 12);
     }
 
     #[test]
@@ -622,10 +725,13 @@ mod tests {
         // Delete the data
         let res = local_pool.delete(addr);
         assert!(res.is_ok());
+        let mut writer = |buf: &mut [u8]| {
+            assert_eq!(buf.len(), 12);
+        };
         // Verify that the slot is free by trying to get a reference to it
-        let res = local_pool.free_element(12);
+        let res = local_pool.free_element(12, &mut writer);
         assert!(res.is_ok());
-        let (addr, buf_ref) = res.unwrap();
+        let addr = res.unwrap();
         assert_eq!(
             addr,
             u64::from(StaticPoolAddr {
@@ -633,7 +739,6 @@ mod tests {
                 packet_idx: 0
             })
         );
-        assert_eq!(buf_ref.len(), 12);
     }
 
     #[test]
@@ -647,29 +752,34 @@ mod tests {
 
         {
             // Verify that the slot is free by trying to get a reference to it
-            let res = local_pool.modify(&addr).expect("Modifying data failed");
-            res[0] = 0;
-            res[1] = 0x42;
+            local_pool
+                .modify(&addr, &mut |buf: &mut [u8]| {
+                    buf[0] = 0;
+                    buf[1] = 0x42;
+                })
+                .expect("Modifying data failed");
         }
 
-        let res = local_pool.read(&addr).expect("Reading back data failed");
-        assert_eq!(res[0], 0);
-        assert_eq!(res[1], 0x42);
-        assert_eq!(res[2], 2);
-        assert_eq!(res[3], 3);
+        local_pool
+            .read(&addr, &mut test_buf)
+            .expect("Reading back data failed");
+        assert_eq!(test_buf[0], 0);
+        assert_eq!(test_buf[1], 0x42);
+        assert_eq!(test_buf[2], 2);
+        assert_eq!(test_buf[3], 3);
     }
 
     #[test]
     fn test_consecutive_reservation() {
         let mut local_pool = basic_small_pool();
         // Reserve two smaller blocks consecutively and verify that the third reservation fails
-        let res = local_pool.free_element(8);
+        let res = local_pool.free_element(8, |_| {});
         assert!(res.is_ok());
-        let (addr0, _) = res.unwrap();
-        let res = local_pool.free_element(8);
+        let addr0 = res.unwrap();
+        let res = local_pool.free_element(8, |_| {});
         assert!(res.is_ok());
-        let (addr1, _) = res.unwrap();
-        let res = local_pool.free_element(8);
+        let addr1 = res.unwrap();
+        let res = local_pool.free_element(8, |_| {});
         assert!(res.is_err());
         let err = res.unwrap_err();
         assert_eq!(err, StoreError::StoreFull(1));
@@ -689,6 +799,7 @@ mod tests {
                 pool_idx: 0,
             }
             .into(),
+            &mut [],
         );
         assert!(res.is_err());
         assert!(matches!(
@@ -720,7 +831,7 @@ mod tests {
             packet_idx: 0,
         }
         .into();
-        let res = local_pool.read(&addr);
+        let res = local_pool.read(&addr, &mut []);
         assert!(res.is_err());
         let err = res.unwrap_err();
         assert!(matches!(
@@ -737,7 +848,7 @@ mod tests {
             packet_idx: 1,
         };
         assert_eq!(addr.raw(), 0x00020001);
-        let res = local_pool.read(&addr.into());
+        let res = local_pool.read(&addr.into(), &mut []);
         assert!(res.is_err());
         let err = res.unwrap_err();
         assert!(matches!(
@@ -759,7 +870,7 @@ mod tests {
     #[test]
     fn test_data_too_large_1() {
         let mut local_pool = basic_small_pool();
-        let res = local_pool.free_element(POOL_MAX_SIZE + 1);
+        let res = local_pool.free_element(POOL_MAX_SIZE + 1, |_| {});
         assert!(res.is_err());
         assert_eq!(
             res.unwrap_err(),
@@ -771,7 +882,7 @@ mod tests {
     fn test_free_element_too_large() {
         let mut local_pool = basic_small_pool();
         // Try to request a slot which is too large
-        let res = local_pool.free_element(20);
+        let res = local_pool.free_element(20, |_| {});
         assert!(res.is_err());
         assert_eq!(res.unwrap_err(), StoreError::DataTooLarge(20));
     }
@@ -813,7 +924,7 @@ mod tests {
         let test_buf: [u8; 16] = [0; 16];
         let addr = local_pool.add(&test_buf).expect("Adding data failed");
         let mut rw_guard = PoolRwGuard::new(&mut local_pool, addr);
-        let _ = rw_guard.modify().expect("modify failed");
+        rw_guard.update(&mut |_| {}).expect("modify failed");
         drop(rw_guard);
         assert!(!local_pool.has_element_at(&addr).expect("Invalid address"));
     }
@@ -824,7 +935,7 @@ mod tests {
         let test_buf: [u8; 16] = [0; 16];
         let addr = local_pool.add(&test_buf).expect("Adding data failed");
         let mut rw_guard = local_pool.modify_with_guard(addr);
-        let _ = rw_guard.modify().expect("modify failed");
+        rw_guard.update(&mut |_| {}).expect("modify failed");
         drop(rw_guard);
         assert!(!local_pool.has_element_at(&addr).expect("Invalid address"));
     }
@@ -840,13 +951,93 @@ mod tests {
         let addr1 = local_pool.add(&test_buf_1).expect("Adding data failed");
         let addr2 = local_pool.add(&test_buf_2).expect("Adding data failed");
         let addr3 = local_pool.add(&test_buf_3).expect("Adding data failed");
-        let tm0_raw = local_pool.modify(&addr0).expect("Modifying data failed");
-        assert_eq!(tm0_raw, test_buf_0);
-        let tm1_raw = local_pool.modify(&addr1).expect("Modifying data failed");
-        assert_eq!(tm1_raw, test_buf_1);
-        let tm2_raw = local_pool.modify(&addr2).expect("Modifying data failed");
-        assert_eq!(tm2_raw, test_buf_2);
-        let tm3_raw = local_pool.modify(&addr3).expect("Modifying data failed");
-        assert_eq!(tm3_raw, test_buf_3);
+        local_pool
+            .modify(&addr0, |buf| {
+                assert_eq!(buf, test_buf_0);
+            })
+            .expect("Modifying data failed");
+        local_pool
+            .modify(&addr1, |buf| {
+                assert_eq!(buf, test_buf_1);
+            })
+            .expect("Modifying data failed");
+        local_pool
+            .modify(&addr2, |buf| {
+                assert_eq!(buf, test_buf_2);
+            })
+            .expect("Modifying data failed");
+        local_pool
+            .modify(&addr3, |buf| {
+                assert_eq!(buf, test_buf_3);
+            })
+            .expect("Modifying data failed");
+    }
+
+    #[test]
+    fn test_spills_to_higher_subpools() {
+        let pool_cfg = StaticPoolConfig::new(vec![(2, 8), (2, 16)], true);
+        let mut local_pool = StaticMemoryPool::new(pool_cfg);
+        local_pool.free_element(8, |_| {}).unwrap();
+        local_pool.free_element(8, |_| {}).unwrap();
+        let mut in_larger_subpool_now = local_pool.free_element(8, |_| {});
+        assert!(in_larger_subpool_now.is_ok());
+        let generic_addr = in_larger_subpool_now.unwrap();
+        let pool_addr = StaticPoolAddr::from(generic_addr);
+        assert_eq!(pool_addr.pool_idx, 1);
+        assert_eq!(pool_addr.packet_idx, 0);
+        assert!(local_pool.has_element_at(&generic_addr).unwrap());
+        in_larger_subpool_now = local_pool.free_element(8, |_| {});
+        assert!(in_larger_subpool_now.is_ok());
+        let generic_addr = in_larger_subpool_now.unwrap();
+        let pool_addr = StaticPoolAddr::from(generic_addr);
+        assert_eq!(pool_addr.pool_idx, 1);
+        assert_eq!(pool_addr.packet_idx, 1);
+        assert!(local_pool.has_element_at(&generic_addr).unwrap());
+    }
+
+    #[test]
+    fn test_spillage_fails_as_well() {
+        let pool_cfg = StaticPoolConfig::new(vec![(1, 8), (1, 16)], true);
+        let mut local_pool = StaticMemoryPool::new(pool_cfg);
+        local_pool.free_element(8, |_| {}).unwrap();
+        local_pool.free_element(8, |_| {}).unwrap();
+        let should_fail = local_pool.free_element(8, |_| {});
+        assert!(should_fail.is_err());
+        if let Err(err) = should_fail {
+            assert_eq!(err, StoreError::StoreFull(1));
+        } else {
+            panic!("unexpected store address");
+        }
+    }
+
+    #[test]
+    fn test_spillage_works_across_multiple_subpools() {
+        let pool_cfg = StaticPoolConfig::new(vec![(1, 8), (1, 12), (1, 16)], true);
+        let mut local_pool = StaticMemoryPool::new(pool_cfg);
+        local_pool.free_element(8, |_| {}).unwrap();
+        local_pool.free_element(12, |_| {}).unwrap();
+        let in_larger_subpool_now = local_pool.free_element(8, |_| {});
+        assert!(in_larger_subpool_now.is_ok());
+        let generic_addr = in_larger_subpool_now.unwrap();
+        let pool_addr = StaticPoolAddr::from(generic_addr);
+        assert_eq!(pool_addr.pool_idx, 2);
+        assert_eq!(pool_addr.packet_idx, 0);
+        assert!(local_pool.has_element_at(&generic_addr).unwrap());
+    }
+
+    #[test]
+    fn test_spillage_fails_across_multiple_subpools() {
+        let pool_cfg = StaticPoolConfig::new(vec![(1, 8), (1, 12), (1, 16)], true);
+        let mut local_pool = StaticMemoryPool::new(pool_cfg);
+        local_pool.free_element(8, |_| {}).unwrap();
+        local_pool.free_element(12, |_| {}).unwrap();
+        local_pool.free_element(16, |_| {}).unwrap();
+        let should_fail = local_pool.free_element(8, |_| {});
+        assert!(should_fail.is_err());
+        if let Err(err) = should_fail {
+            assert_eq!(err, StoreError::StoreFull(2));
+        } else {
+            panic!("unexpected store address");
+        }
     }
 }

satrs-core/src/pus/mod.rs

@@ -390,7 +390,7 @@ mod alloc_mod {
 #[cfg(feature = "std")]
 #[cfg_attr(doc_cfg, doc(cfg(feature = "std")))]
 pub mod std_mod {
-    use crate::pool::{PoolProviderMemInPlaceWithGuards, SharedStaticMemoryPool, StoreAddr};
+    use crate::pool::{PoolProvider, PoolProviderWithGuards, SharedStaticMemoryPool, StoreAddr};
     use crate::pus::verification::{
         StdVerifReporterWithSender, TcStateAccepted, VerificationToken,
     };
@@ -789,12 +789,15 @@ pub mod std_mod {
                 .shared_tc_store
                 .write()
                 .map_err(|_| PusPacketHandlingError::EcssTmtc(EcssTmtcError::StoreLock))?;
-            let tc_guard = tc_pool.read_with_guard(addr);
-            let tc_raw = tc_guard.read().unwrap();
-            if tc_raw.len() > self.pus_buf.len() {
-                return Err(PusPacketHandlingError::PusPacketTooLarge(tc_raw.len()));
+            let tc_size = tc_pool
+                .len_of_data(&addr)
+                .map_err(|e| PusPacketHandlingError::EcssTmtc(EcssTmtcError::Store(e)))?;
+            if tc_size > self.pus_buf.len() {
+                return Err(PusPacketHandlingError::PusPacketTooLarge(tc_size));
             }
-            self.pus_buf[0..tc_raw.len()].copy_from_slice(tc_raw);
+            let tc_guard = tc_pool.read_with_guard(addr);
+            // TODO: Proper error handling.
+            tc_guard.read(&mut self.pus_buf[0..tc_size]).unwrap();
             Ok(())
         }
     }
@@ -947,8 +950,7 @@ pub mod tests {
     use spacepackets::CcsdsPacket;
 
     use crate::pool::{
-        PoolProviderMemInPlace, SharedStaticMemoryPool, StaticMemoryPool, StaticPoolConfig,
-        StoreAddr,
+        PoolProvider, SharedStaticMemoryPool, StaticMemoryPool, StaticPoolConfig, StoreAddr,
     };
     use crate::pus::verification::RequestId;
     use crate::tmtc::tm_helper::SharedTmPool;
@@ -1015,7 +1017,7 @@ pub mod tests {
         ///
         /// The PUS service handler is instantiated with a [EcssTcInStoreConverter].
         pub fn new() -> (Self, PusServiceHelper<EcssTcInSharedStoreConverter>) {
-            let pool_cfg = StaticPoolConfig::new(vec![(16, 16), (8, 32), (4, 64)]);
+            let pool_cfg = StaticPoolConfig::new(vec![(16, 16), (8, 32), (4, 64)], false);
             let tc_pool = StaticMemoryPool::new(pool_cfg.clone());
             let tm_pool = StaticMemoryPool::new(pool_cfg);
             let shared_tc_pool = SharedStaticMemoryPool::new(RwLock::new(tc_pool));
@@ -1078,8 +1080,8 @@ pub mod tests {
             assert!(next_msg.is_ok());
             let tm_addr = next_msg.unwrap();
             let tm_pool = self.tm_pool.0.read().unwrap();
-            let tm_raw = tm_pool.read(&tm_addr).unwrap();
-            self.tm_buf[0..tm_raw.len()].copy_from_slice(tm_raw);
+            let tm_raw = tm_pool.read_as_vec(&tm_addr).unwrap();
+            self.tm_buf[0..tm_raw.len()].copy_from_slice(&tm_raw);
             PusTmReader::new(&self.tm_buf, 7).unwrap().0
         }
 
@@ -1096,8 +1098,8 @@ pub mod tests {
             assert!(next_msg.is_ok());
             let tm_addr = next_msg.unwrap();
             let tm_pool = self.tm_pool.0.read().unwrap();
-            let tm_raw = tm_pool.read(&tm_addr).unwrap();
-            let tm = PusTmReader::new(tm_raw, 7).unwrap().0;
+            let tm_raw = tm_pool.read_as_vec(&tm_addr).unwrap();
+            let tm = PusTmReader::new(&tm_raw, 7).unwrap().0;
             assert_eq!(PusPacket::service(&tm), 1);
             assert_eq!(PusPacket::subservice(&tm), subservice);
             assert_eq!(tm.apid(), TEST_APID);

satrs-core/src/pus/scheduler.rs

@@ -16,7 +16,7 @@ use spacepackets::{ByteConversionError, CcsdsPacket};
 #[cfg(feature = "std")]
 use std::error::Error;
 
-use crate::pool::{PoolProviderMemInPlace, StoreError};
+use crate::pool::{PoolProvider, StoreError};
 #[cfg(feature = "alloc")]
 pub use alloc_mod::*;
 
@@ -238,13 +238,11 @@ impl Error for ScheduleError {
     }
 }
 
-pub trait PusSchedulerInterface {
+/// Generic trait for scheduler objects which are able to schedule ECSS PUS C packets.
+pub trait PusSchedulerProvider {
     type TimeProvider: CcsdsTimeProvider + TimeReader;
 
-    fn reset(
-        &mut self,
-        store: &mut (impl PoolProviderMemInPlace + ?Sized),
-    ) -> Result<(), StoreError>;
+    fn reset(&mut self, store: &mut (impl PoolProvider + ?Sized)) -> Result<(), StoreError>;
 
     fn is_enabled(&self) -> bool;
 
@@ -267,7 +265,7 @@ pub trait PusSchedulerInterface {
     fn insert_wrapped_tc<TimeProvider>(
         &mut self,
         pus_tc: &(impl IsPusTelecommand + PusPacket + GenericPusTcSecondaryHeader),
-        pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+        pool: &mut (impl PoolProvider + ?Sized),
     ) -> Result<TcInfo, ScheduleError> {
         if PusPacket::service(pus_tc) != 11 {
             return Err(ScheduleError::WrongService(PusPacket::service(pus_tc)));
@@ -293,7 +291,7 @@ pub trait PusSchedulerInterface {
         &mut self,
         time_stamp: UnixTimestamp,
         tc: &[u8],
-        pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+        pool: &mut (impl PoolProvider + ?Sized),
     ) -> Result<TcInfo, ScheduleError> {
         let check_tc = PusTcReader::new(tc)?;
         if PusPacket::service(&check_tc.0) == 11 && PusPacket::subservice(&check_tc.0) == 4 {
@@ -343,7 +341,7 @@ pub fn generate_insert_telecommand_app_data(
 #[cfg(feature = "alloc")]
 pub mod alloc_mod {
     use super::*;
-    use crate::pool::{PoolProviderMemInPlace, StoreAddr, StoreError};
+    use crate::pool::{PoolProvider, StoreAddr, StoreError};
     use alloc::collections::btree_map::{Entry, Range};
     use alloc::collections::BTreeMap;
     use alloc::vec;
@@ -379,7 +377,7 @@ pub mod alloc_mod {
     /// This is the core data structure for scheduling PUS telecommands with [alloc] support.
     ///
     /// It is assumed that the actual telecommand data is stored in a separate TC pool offering
-    /// a [crate::pool::PoolProviderMemInPlace] API. This data structure just tracks the store
+    /// a [crate::pool::PoolProvider] API. This data structure just tracks the store
     /// addresses and their release times and offers a convenient API to insert and release
     /// telecommands and perform other functionality specified by the ECSS standard in section 6.11.
     /// The time is tracked as a [spacepackets::time::UnixTimestamp] but the only requirement to
@@ -413,6 +411,8 @@ pub mod alloc_mod {
         /// * `time_margin` - This time margin is used when inserting new telecommands into the
         ///      schedule. If the release time of a new telecommand is earlier than the time margin
         ///      added to the current time, it will not be inserted into the schedule.
+        /// * `tc_buf_size` - Buffer for temporary storage of telecommand packets. This buffer
+        ///      should be large enough to accomodate the largest expected TC packets.
         pub fn new(init_current_time: UnixTimestamp, time_margin: Duration) -> Self {
             PusScheduler {
                 tc_map: Default::default(),
@@ -476,7 +476,7 @@ pub mod alloc_mod {
             &mut self,
             time_stamp: UnixTimestamp,
             tc: &[u8],
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<TcInfo, ScheduleError> {
             let check_tc = PusTcReader::new(tc)?;
             if PusPacket::service(&check_tc.0) == 11 && PusPacket::subservice(&check_tc.0) == 4 {
@@ -499,7 +499,7 @@ pub mod alloc_mod {
         pub fn insert_wrapped_tc_cds_short(
             &mut self,
             pus_tc: &PusTc,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<TcInfo, ScheduleError> {
             self.insert_wrapped_tc::<cds::TimeProvider>(pus_tc, pool)
         }
@@ -509,7 +509,7 @@ pub mod alloc_mod {
         pub fn insert_wrapped_tc_cds_long(
             &mut self,
             pus_tc: &PusTc,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<TcInfo, ScheduleError> {
             self.insert_wrapped_tc::<cds::TimeProvider<DaysLen24Bits>>(pus_tc, pool)
         }
@@ -525,7 +525,7 @@ pub mod alloc_mod {
         pub fn delete_by_time_filter<TimeProvider: CcsdsTimeProvider + Clone>(
             &mut self,
             time_window: TimeWindow<TimeProvider>,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<u64, (u64, StoreError)> {
             let range = self.retrieve_by_time_filter(time_window);
             let mut del_packets = 0;
@@ -555,7 +555,7 @@ pub mod alloc_mod {
         /// the last deletion will be supplied in addition to the number of deleted commands.
         pub fn delete_all(
             &mut self,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<u64, (u64, StoreError)> {
             self.delete_by_time_filter(TimeWindow::<cds::TimeProvider>::new_select_all(), pool)
         }
@@ -613,7 +613,7 @@ pub mod alloc_mod {
         pub fn delete_by_request_id_and_from_pool(
             &mut self,
             req_id: &RequestId,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> Result<bool, StoreError> {
             if let DeletionResult::WithStoreDeletion(v) =
                 self.delete_by_request_id_internal_with_store_deletion(req_id, pool)
@@ -645,7 +645,7 @@ pub mod alloc_mod {
         fn delete_by_request_id_internal_with_store_deletion(
             &mut self,
             req_id: &RequestId,
-            pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+            pool: &mut (impl PoolProvider + ?Sized),
         ) -> DeletionResult {
             let mut idx_found = None;
             for time_bucket in &mut self.tc_map {
@@ -675,7 +675,8 @@ pub mod alloc_mod {
         /// Utility method which calls [Self::telecommands_to_release] and then calls a releaser
         /// closure for each telecommand which should be released. This function will also delete
         /// the telecommands from the holding store after calling the release closure if the user
-        /// returns [true] from the release closure.
+        /// returns [true] from the release closure. A buffer must be provided to hold the
+        /// telecommands for the release process.
         ///
         /// # Arguments
         ///
@@ -685,18 +686,55 @@ pub mod alloc_mod {
         ///     note that returning false might lead to memory leaks if the TC is not cleared from
         ///     the store in some other way.
         /// * `tc_store` - The holding store of the telecommands.
+        /// * `tc_buf` - Buffer to hold each telecommand being released.
+        pub fn release_telecommands_with_buffer<R: FnMut(bool, &TcInfo, &[u8]) -> bool>(
+            &mut self,
+            releaser: R,
+            tc_store: &mut (impl PoolProvider + ?Sized),
+            tc_buf: &mut [u8],
+        ) -> Result<u64, (u64, StoreError)> {
+            self.release_telecommands_internal(releaser, tc_store, Some(tc_buf))
+        }
+
+        /// This functions is almost identical to [Self::release_telecommands_with_buffer] but does
+        /// not require a user provided TC buffer because it will always use the
+        /// [PoolProvider::read_as_vec] API to read the TC packets.
+        ///
+        /// However, this might also perform frequent allocations for all telecommands being
+        /// released.
         pub fn release_telecommands<R: FnMut(bool, &TcInfo, &[u8]) -> bool>(
+            &mut self,
+            releaser: R,
+            tc_store: &mut (impl PoolProvider + ?Sized),
+        ) -> Result<u64, (u64, StoreError)> {
+            self.release_telecommands_internal(releaser, tc_store, None)
+        }
+
+        fn release_telecommands_internal<R: FnMut(bool, &TcInfo, &[u8]) -> bool>(
             &mut self,
             mut releaser: R,
-            tc_store: &mut (impl PoolProviderMemInPlace + ?Sized),
+            tc_store: &mut (impl PoolProvider + ?Sized),
+            mut tc_buf: Option<&mut [u8]>,
         ) -> Result<u64, (u64, StoreError)> {
             let tcs_to_release = self.telecommands_to_release();
             let mut released_tcs = 0;
             let mut store_error = Ok(());
             for tc in tcs_to_release {
                 for info in tc.1 {
-                    let tc = tc_store.read(&info.addr).map_err(|e| (released_tcs, e))?;
-                    let should_delete = releaser(self.enabled, info, tc);
+                    let should_delete = match tc_buf.as_mut() {
+                        Some(buf) => {
+                            tc_store
+                                .read(&info.addr, buf)
+                                .map_err(|e| (released_tcs, e))?;
+                            releaser(self.enabled, info, buf)
+                        }
+                        None => {
+                            let tc = tc_store
+                                .read_as_vec(&info.addr)
+                                .map_err(|e| (released_tcs, e))?;
+                            releaser(self.enabled, info, &tc)
+                        }
+                    };
                     released_tcs += 1;
                     if should_delete {
                         let res = tc_store.delete(info.addr);
@@ -721,16 +759,17 @@ pub mod alloc_mod {
         pub fn release_telecommands_no_deletion<R: FnMut(bool, &TcInfo, &[u8])>(
             &mut self,
             mut releaser: R,
-            tc_store: &(impl PoolProviderMemInPlace + ?Sized),
+            tc_store: &(impl PoolProvider + ?Sized),
+            tc_buf: &mut [u8],
         ) -> Result<Vec<TcInfo>, (Vec<TcInfo>, StoreError)> {
             let tcs_to_release = self.telecommands_to_release();
             let mut released_tcs = Vec::new();
             for tc in tcs_to_release {
                 for info in tc.1 {
-                    let tc = tc_store
-                        .read(&info.addr)
+                    tc_store
+                        .read(&info.addr, tc_buf)
                         .map_err(|e| (released_tcs.clone(), e))?;
-                    releaser(self.is_enabled(), info, tc);
+                    releaser(self.is_enabled(), info, tc_buf);
                     released_tcs.push(*info);
                 }
             }
@@ -744,7 +783,7 @@ pub mod alloc_mod {
         }
     }
 
-    impl PusSchedulerInterface for PusScheduler {
+    impl PusSchedulerProvider for PusScheduler {
         type TimeProvider = cds::TimeProvider;
 
         /// This will disable the scheduler and clear the schedule as specified in 6.11.4.4.
@@ -753,10 +792,7 @@ pub mod alloc_mod {
         /// The holding store for the telecommands needs to be passed so all the stored telecommands
         /// can be deleted to avoid a memory leak. If at last one deletion operation fails, the error
         /// will be returned but the method will still try to delete all the commands in the schedule.
-        fn reset(
-            &mut self,
-            store: &mut (impl PoolProviderMemInPlace + ?Sized),
-        ) -> Result<(), StoreError> {
+        fn reset(&mut self, store: &mut (impl PoolProvider + ?Sized)) -> Result<(), StoreError> {
             self.enabled = false;
             let mut deletion_ok = Ok(());
             for tc_lists in &mut self.tc_map {
@@ -814,8 +850,7 @@ pub mod alloc_mod {
 mod tests {
     use super::*;
     use crate::pool::{
-        PoolProviderMemInPlace, StaticMemoryPool, StaticPoolAddr, StaticPoolConfig, StoreAddr,
-        StoreError,
+        PoolProvider, StaticMemoryPool, StaticPoolAddr, StaticPoolConfig, StoreAddr, StoreError,
     };
     use alloc::collections::btree_map::Range;
     use spacepackets::ecss::tc::{PusTcCreator, PusTcReader, PusTcSecondaryHeader};
@@ -911,7 +946,7 @@ mod tests {
 
     #[test]
     fn test_reset() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
@@ -1063,7 +1098,7 @@ mod tests {
     }
     #[test]
     fn test_release_telecommands() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
@@ -1088,8 +1123,9 @@ mod tests {
         // test 1: too early, no tcs
         scheduler.update_time(UnixTimestamp::new_only_seconds(99));
 
+        let mut tc_buf: [u8; 128] = [0; 128];
         scheduler
-            .release_telecommands(&mut test_closure_1, &mut pool)
+            .release_telecommands_with_buffer(&mut test_closure_1, &mut pool, &mut tc_buf)
             .expect("deletion failed");
 
         // test 2: exact time stamp of tc, releases 1 tc
@@ -1111,7 +1147,7 @@ mod tests {
         scheduler.update_time(UnixTimestamp::new_only_seconds(206));
 
         released = scheduler
-            .release_telecommands(&mut test_closure_2, &mut pool)
+            .release_telecommands_with_buffer(&mut test_closure_2, &mut pool, &mut tc_buf)
             .expect("deletion failed");
         assert_eq!(released, 1);
         // TC is deleted.
@@ -1128,7 +1164,7 @@ mod tests {
 
     #[test]
     fn release_multi_with_same_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
@@ -1157,9 +1193,10 @@ mod tests {
 
         // test 1: too early, no tcs
         scheduler.update_time(UnixTimestamp::new_only_seconds(99));
+        let mut tc_buf: [u8; 128] = [0; 128];
 
         let mut released = scheduler
-            .release_telecommands(&mut test_closure, &mut pool)
+            .release_telecommands_with_buffer(&mut test_closure, &mut pool, &mut tc_buf)
             .expect("deletion failed");
         assert_eq!(released, 0);
 
@@ -1185,7 +1222,7 @@ mod tests {
 
     #[test]
     fn release_with_scheduler_disabled() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
@@ -1209,11 +1246,13 @@ mod tests {
             true
         };
 
+        let mut tc_buf: [u8; 128] = [0; 128];
+
         // test 1: too early, no tcs
         scheduler.update_time(UnixTimestamp::new_only_seconds(99));
 
         scheduler
-            .release_telecommands(&mut test_closure_1, &mut pool)
+            .release_telecommands_with_buffer(&mut test_closure_1, &mut pool, &mut tc_buf)
             .expect("deletion failed");
 
         // test 2: exact time stamp of tc, releases 1 tc
@@ -1253,7 +1292,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut buf: [u8; 32] = [0; 32];
         let tc_info_0 = ping_tc_to_store(&mut pool, &mut buf, 0, None);
 
@@ -1267,8 +1306,9 @@ mod tests {
 
         assert!(pool.has_element_at(&tc_info_0.addr()).unwrap());
 
-        let data = pool.read(&tc_info_0.addr()).unwrap();
-        let check_tc = PusTcReader::new(data).expect("incorrect Pus tc raw data");
+        let mut read_buf: [u8; 64] = [0; 64];
+        pool.read(&tc_info_0.addr(), &mut read_buf).unwrap();
+        let check_tc = PusTcReader::new(&read_buf).expect("incorrect Pus tc raw data");
         assert_eq!(check_tc.0, base_ping_tc_simple_ctor(0, None));
 
         assert_eq!(scheduler.num_scheduled_telecommands(), 1);
@@ -1289,8 +1329,9 @@ mod tests {
             .release_telecommands(&mut test_closure, &mut pool)
             .unwrap();
 
-        let data = pool.read(&addr_vec[0]).unwrap();
-        let check_tc = PusTcReader::new(data).expect("incorrect Pus tc raw data");
+        let read_len = pool.read(&addr_vec[0], &mut read_buf).unwrap();
+        let check_tc = PusTcReader::new(&read_buf).expect("incorrect Pus tc raw data");
+        assert_eq!(read_len, check_tc.1);
         assert_eq!(check_tc.0, base_ping_tc_simple_ctor(0, None));
     }
 
@@ -1299,7 +1340,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
 
         let mut buf: [u8; 32] = [0; 32];
         let tc = scheduled_tc(UnixTimestamp::new_only_seconds(100), &mut buf);
@@ -1313,8 +1354,9 @@ mod tests {
 
         assert!(pool.has_element_at(&info.addr).unwrap());
 
-        let data = pool.read(&info.addr).unwrap();
-        let check_tc = PusTcReader::new(data).expect("incorrect Pus tc raw data");
+        let read_len = pool.read(&info.addr, &mut buf).unwrap();
+        let check_tc = PusTcReader::new(&buf).expect("incorrect Pus tc raw data");
+        assert_eq!(read_len, check_tc.1);
         assert_eq!(check_tc.0, base_ping_tc_simple_ctor(0, None));
 
         assert_eq!(scheduler.num_scheduled_telecommands(), 1);
@@ -1331,12 +1373,15 @@ mod tests {
             false
         };
 
+        let mut tc_buf: [u8; 64] = [0; 64];
+
         scheduler
-            .release_telecommands(&mut test_closure, &mut pool)
+            .release_telecommands_with_buffer(&mut test_closure, &mut pool, &mut tc_buf)
             .unwrap();
 
-        let data = pool.read(&addr_vec[0]).unwrap();
-        let check_tc = PusTcReader::new(data).expect("incorrect PUS tc raw data");
+        let read_len = pool.read(&addr_vec[0], &mut buf).unwrap();
+        let check_tc = PusTcReader::new(&buf).expect("incorrect PUS tc raw data");
+        assert_eq!(read_len, check_tc.1);
         assert_eq!(check_tc.0, base_ping_tc_simple_ctor(0, None));
     }
 
@@ -1345,7 +1390,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
 
         let mut buf: [u8; 32] = [0; 32];
         let tc = wrong_tc_service(UnixTimestamp::new_only_seconds(100), &mut buf);
@@ -1368,7 +1413,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
 
         let mut buf: [u8; 32] = [0; 32];
         let tc = wrong_tc_subservice(UnixTimestamp::new_only_seconds(100), &mut buf);
@@ -1390,7 +1435,7 @@ mod tests {
     fn insert_wrapped_tc_faulty_app_data() {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let tc = invalid_time_tagged_cmd();
         let insert_res = scheduler.insert_wrapped_tc::<cds::TimeProvider>(&tc, &mut pool);
         assert!(insert_res.is_err());
@@ -1405,7 +1450,7 @@ mod tests {
     fn insert_doubly_wrapped_time_tagged_cmd() {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut buf: [u8; 64] = [0; 64];
         let tc = double_wrapped_time_tagged_tc(UnixTimestamp::new_only_seconds(50), &mut buf);
         let insert_res = scheduler.insert_wrapped_tc::<cds::TimeProvider>(&tc, &mut pool);
@@ -1441,7 +1486,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
 
         let mut buf: [u8; 32] = [0; 32];
 
@@ -1465,7 +1510,7 @@ mod tests {
 
     #[test]
     fn test_store_error_propagation_release() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let mut buf: [u8; 32] = [0; 32];
@@ -1500,7 +1545,7 @@ mod tests {
 
     #[test]
     fn test_store_error_propagation_reset() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let mut buf: [u8; 32] = [0; 32];
@@ -1524,7 +1569,7 @@ mod tests {
 
     #[test]
     fn test_delete_by_req_id_simple_retrieve_addr() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let mut buf: [u8; 32] = [0; 32];
@@ -1543,7 +1588,7 @@ mod tests {
 
     #[test]
     fn test_delete_by_req_id_simple_delete_all() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let mut buf: [u8; 32] = [0; 32];
@@ -1562,7 +1607,7 @@ mod tests {
 
     #[test]
     fn test_delete_by_req_id_complex() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let mut buf: [u8; 32] = [0; 32];
@@ -1609,7 +1654,7 @@ mod tests {
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(1, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(1, 64)], false));
 
         let mut buf: [u8; 32] = [0; 32];
         // Store is full after this.
@@ -1648,7 +1693,7 @@ mod tests {
 
     #[test]
     fn test_time_window_retrieval_select_all() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let tc_info_0 = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1679,7 +1724,7 @@ mod tests {
 
     #[test]
     fn test_time_window_retrieval_select_from_stamp() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let _ = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1710,7 +1755,7 @@ mod tests {
 
     #[test]
     fn test_time_window_retrieval_select_to_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let tc_info_0 = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1741,7 +1786,7 @@ mod tests {
 
     #[test]
     fn test_time_window_retrieval_select_from_time_to_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let _ = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1776,7 +1821,7 @@ mod tests {
 
     #[test]
     fn test_deletion_all() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1803,7 +1848,7 @@ mod tests {
 
     #[test]
     fn test_deletion_from_start_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1824,7 +1869,7 @@ mod tests {
 
     #[test]
     fn test_deletion_to_end_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let cmd_0_to_delete = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1846,7 +1891,7 @@ mod tests {
 
     #[test]
     fn test_deletion_from_start_time_to_end_time() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
         let cmd_out_of_range_0 = insert_command_with_release_time(&mut pool, &mut scheduler, 0, 50);
@@ -1875,7 +1920,7 @@ mod tests {
 
     #[test]
     fn test_release_without_deletion() {
-        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)]));
+        let mut pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(10, 32), (5, 64)], false));
         let mut scheduler =
             PusScheduler::new(UnixTimestamp::new_only_seconds(0), Duration::from_secs(5));
 
@@ -1903,8 +1948,9 @@ mod tests {
 
         scheduler.update_time(UnixTimestamp::new_only_seconds(205));
 
+        let mut tc_buf: [u8; 64] = [0; 64];
         let tc_info_vec = scheduler
-            .release_telecommands_no_deletion(&mut test_closure_1, &pool)
+            .release_telecommands_no_deletion(&mut test_closure_1, &pool, &mut tc_buf)
             .expect("deletion failed");
         assert_eq!(tc_info_vec[0], tc_info_0);
         assert_eq!(tc_info_vec[1], tc_info_1);

satrs-core/src/pus/scheduler_srv.rs

@@ -1,6 +1,6 @@
-use super::scheduler::PusSchedulerInterface;
+use super::scheduler::PusSchedulerProvider;
 use super::{EcssTcInMemConverter, PusServiceBase, PusServiceHelper};
-use crate::pool::PoolProviderMemInPlace;
+use crate::pool::PoolProvider;
 use crate::pus::{PusPacketHandlerResult, PusPacketHandlingError};
 use alloc::string::ToString;
 use spacepackets::ecss::{scheduling, PusPacket};
@@ -16,13 +16,13 @@ use spacepackets::time::cds::TimeProvider;
 /// telecommands when applicable.
 pub struct PusService11SchedHandler<
     TcInMemConverter: EcssTcInMemConverter,
-    Scheduler: PusSchedulerInterface,
+    PusScheduler: PusSchedulerProvider,
 > {
     pub service_helper: PusServiceHelper<TcInMemConverter>,
-    scheduler: Scheduler,
+    scheduler: PusScheduler,
 }
 
-impl<TcInMemConverter: EcssTcInMemConverter, Scheduler: PusSchedulerInterface>
+impl<TcInMemConverter: EcssTcInMemConverter, Scheduler: PusSchedulerProvider>
     PusService11SchedHandler<TcInMemConverter, Scheduler>
 {
     pub fn new(service_helper: PusServiceHelper<TcInMemConverter>, scheduler: Scheduler) -> Self {
@@ -42,7 +42,7 @@ impl<TcInMemConverter: EcssTcInMemConverter, Scheduler: PusSchedulerInterface>
 
     pub fn handle_one_tc(
         &mut self,
-        sched_tc_pool: &mut (impl PoolProviderMemInPlace + ?Sized),
+        sched_tc_pool: &mut (impl PoolProvider + ?Sized),
     ) -> Result<PusPacketHandlerResult, PusPacketHandlingError> {
         let possible_packet = self.service_helper.retrieve_and_accept_next_packet()?;
         if possible_packet.is_none() {
@@ -173,7 +173,7 @@ mod tests {
     use crate::pool::{StaticMemoryPool, StaticPoolConfig};
     use crate::pus::tests::TEST_APID;
     use crate::pus::{
-        scheduler::{self, PusSchedulerInterface, TcInfo},
+        scheduler::{self, PusSchedulerProvider, TcInfo},
         tests::{PusServiceHandlerWithSharedStoreCommon, PusTestHarness},
         verification::{RequestId, TcStateAccepted, VerificationToken},
         EcssTcInSharedStoreConverter,
@@ -201,7 +201,7 @@ mod tests {
     impl Pus11HandlerWithStoreTester {
         pub fn new() -> Self {
             let test_scheduler = TestScheduler::default();
-            let pool_cfg = StaticPoolConfig::new(alloc::vec![(16, 16), (8, 32), (4, 64)]);
+            let pool_cfg = StaticPoolConfig::new(alloc::vec![(16, 16), (8, 32), (4, 64)], false);
             let sched_tc_pool = StaticMemoryPool::new(pool_cfg.clone());
             let (common, srv_handler) = PusServiceHandlerWithSharedStoreCommon::new();
             Self {
@@ -232,12 +232,12 @@ mod tests {
         inserted_tcs: VecDeque<TcInfo>,
     }
 
-    impl PusSchedulerInterface for TestScheduler {
+    impl PusSchedulerProvider for TestScheduler {
         type TimeProvider = cds::TimeProvider;
 
         fn reset(
             &mut self,
-            _store: &mut (impl crate::pool::PoolProviderMemInPlace + ?Sized),
+            _store: &mut (impl crate::pool::PoolProvider + ?Sized),
         ) -> Result<(), crate::pool::StoreError> {
             self.reset_count += 1;
             Ok(())

satrs-core/src/pus/verification.rs

@@ -15,7 +15,7 @@
 //! ```
 //! use std::sync::{Arc, mpsc, RwLock};
 //! use std::time::Duration;
-//! use satrs_core::pool::{PoolProviderMemInPlaceWithGuards, StaticMemoryPool, StaticPoolConfig};
+//! use satrs_core::pool::{PoolProviderWithGuards, StaticMemoryPool, StaticPoolConfig};
 //! use satrs_core::pus::verification::{VerificationReporterCfg, VerificationReporterWithSender};
 //! use satrs_core::seq_count::SeqCountProviderSimple;
 //! use satrs_core::pus::MpscTmInSharedPoolSender;
@@ -28,7 +28,7 @@
 //! const EMPTY_STAMP: [u8; 7] = [0; 7];
 //! const TEST_APID: u16 = 0x02;
 //!
-//! let pool_cfg = StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)]);
+//! let pool_cfg = StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)], false);
 //! let tm_pool = StaticMemoryPool::new(pool_cfg.clone());
 //! let shared_tm_store = SharedTmPool::new(tm_pool);
 //! let tm_store = shared_tm_store.clone_backing_pool();
@@ -56,9 +56,7 @@
 //!     {
 //!         let mut rg = tm_store.write().expect("Error locking shared pool");
 //!         let store_guard = rg.read_with_guard(addr);
-//!         let slice = store_guard.read().expect("Error reading TM slice");
-//!         tm_len = slice.len();
-//!         tm_buf[0..tm_len].copy_from_slice(slice);
+//!         tm_len = store_guard.read(&mut tm_buf).expect("Error reading TM slice");
 //!     }
 //!     let (pus_tm, _) = PusTmReader::new(&tm_buf[0..tm_len], 7)
 //!        .expect("Error reading verification TM");
@@ -1325,7 +1323,7 @@ mod std_mod {
 
 #[cfg(test)]
 mod tests {
-    use crate::pool::{PoolProviderMemInPlaceWithGuards, StaticMemoryPool, StaticPoolConfig};
+    use crate::pool::{PoolProviderWithGuards, StaticMemoryPool, StaticPoolConfig};
     use crate::pus::tests::CommonTmInfo;
     use crate::pus::verification::{
         EcssTmSenderCore, EcssTmtcError, FailParams, FailParamsWithStep, RequestId, TcStateNone,
@@ -1486,7 +1484,7 @@ mod tests {
 
     #[test]
     fn test_mpsc_verif_send_sync() {
-        let pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(8, 8)]));
+        let pool = StaticMemoryPool::new(StaticPoolConfig::new(vec![(8, 8)], false));
         let shared_tm_store = SharedTmPool::new(pool);
         let (tx, _) = mpsc::channel();
         let mpsc_verif_sender =
@@ -1547,7 +1545,7 @@ mod tests {
         let mut sender = TestSender::default();
         let fail_code = EcssEnumU16::new(2);
         let fail_params = FailParams::new(Some(stamp_buf.as_slice()), &fail_code, None);
-        b.vr.acceptance_failure(tok, &mut sender, fail_params)
+        b.vr.acceptance_failure(tok, &sender, fail_params)
             .expect("Sending acceptance success failed");
         acceptance_fail_check(&mut sender, tok.req_id, stamp_buf);
     }
@@ -1682,12 +1680,10 @@ mod tests {
         );
 
         let accepted_token =
-            b.vr.acceptance_success(tok, &mut sender, Some(&EMPTY_STAMP))
+            b.vr.acceptance_success(tok, &sender, Some(&EMPTY_STAMP))
                 .expect("Sending acceptance success failed");
-        let empty =
-            b.vr.start_failure(accepted_token, &mut sender, fail_params)
-                .expect("Start failure failure");
-        assert_eq!(empty, ());
+        b.vr.start_failure(accepted_token, &mut sender, fail_params)
+            .expect("Start failure failure");
         start_fail_check(&mut sender, tok.req_id, fail_data_raw);
     }
 
@@ -1779,23 +1775,23 @@ mod tests {
         let mut sender = TestSender::default();
         let accepted_token = b
             .rep()
-            .acceptance_success(tok, &mut sender, Some(&EMPTY_STAMP))
+            .acceptance_success(tok, &sender, Some(&EMPTY_STAMP))
             .expect("Sending acceptance success failed");
         let started_token = b
             .rep()
-            .start_success(accepted_token, &mut sender, Some(&[0, 1, 0, 1, 0, 1, 0]))
+            .start_success(accepted_token, &sender, Some(&[0, 1, 0, 1, 0, 1, 0]))
             .expect("Sending start success failed");
         b.rep()
             .step_success(
                 &started_token,
-                &mut sender,
+                &sender,
                 Some(&EMPTY_STAMP),
                 EcssEnumU8::new(0),
             )
             .expect("Sending step 0 success failed");
         b.vr.step_success(
             &started_token,
-            &mut sender,
+            &sender,
             Some(&EMPTY_STAMP),
             EcssEnumU8::new(1),
         )
@@ -2139,9 +2135,9 @@ mod tests {
     }
 
     #[test]
-    // TODO: maybe a bit more extensive testing, all I have time for right now
     fn test_seq_count_increment() {
-        let pool_cfg = StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)]);
+        let pool_cfg =
+            StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)], false);
         let tm_pool = StaticMemoryPool::new(pool_cfg.clone());
         let shared_tm_store = SharedTmPool::new(tm_pool);
         let shared_tm_pool = shared_tm_store.clone_backing_pool();
@@ -2176,9 +2172,9 @@ mod tests {
             {
                 let mut rg = shared_tm_pool.write().expect("Error locking shared pool");
                 let store_guard = rg.read_with_guard(addr);
-                let slice = store_guard.read().expect("Error reading TM slice");
-                tm_len = slice.len();
-                tm_buf[0..tm_len].copy_from_slice(slice);
+                tm_len = store_guard
+                    .read(&mut tm_buf)
+                    .expect("Error reading TM slice");
             }
             let (pus_tm, _) =
                 PusTmReader::new(&tm_buf[0..tm_len], 7).expect("Error reading verification TM");

satrs-core/src/tmtc/tm_helper.rs

@@ -8,9 +8,7 @@ pub use std_mod::*;
 
 #[cfg(feature = "std")]
 pub mod std_mod {
-    use crate::pool::{
-        PoolProviderMemInPlace, SharedStaticMemoryPool, StaticMemoryPool, StoreAddr,
-    };
+    use crate::pool::{PoolProvider, SharedStaticMemoryPool, StaticMemoryPool, StoreAddr};
     use crate::pus::EcssTmtcError;
     use spacepackets::ecss::tm::PusTmCreator;
     use spacepackets::ecss::WritablePusPacket;
@@ -37,10 +35,11 @@ pub mod std_mod {
 
         pub fn add_pus_tm(&self, pus_tm: &PusTmCreator) -> Result<StoreAddr, EcssTmtcError> {
             let mut pg = self.0.write().map_err(|_| EcssTmtcError::StoreLock)?;
-            let (addr, buf) = pg.free_element(pus_tm.len_written())?;
-            pus_tm
-                .write_to_bytes(buf)
-                .expect("writing PUS TM to store failed");
+            let addr = pg.free_element(pus_tm.len_written(), |buf| {
+                pus_tm
+                    .write_to_bytes(buf)
+                    .expect("writing PUS TM to store failed");
+            })?;
             Ok(addr)
         }
     }

satrs-core/tests/pools.rs

@@ -1,6 +1,4 @@
-use satrs_core::pool::{
-    PoolGuard, PoolProviderMemInPlace, StaticMemoryPool, StaticPoolConfig, StoreAddr,
-};
+use satrs_core::pool::{PoolGuard, PoolProvider, StaticMemoryPool, StaticPoolConfig, StoreAddr};
 use std::ops::DerefMut;
 use std::sync::mpsc;
 use std::sync::mpsc::{Receiver, Sender};
@@ -11,7 +9,7 @@ const DUMMY_DATA: [u8; 4] = [0, 1, 2, 3];
 
 #[test]
 fn threaded_usage() {
-    let pool_cfg = StaticPoolConfig::new(vec![(16, 6), (32, 3), (8, 12)]);
+    let pool_cfg = StaticPoolConfig::new(vec![(16, 6), (32, 3), (8, 12)], false);
     let shared_pool = Arc::new(RwLock::new(StaticMemoryPool::new(pool_cfg)));
     let shared_clone = shared_pool.clone();
     let (tx, rx): (Sender<StoreAddr>, Receiver<StoreAddr>) = mpsc::channel();
@@ -27,8 +25,10 @@ fn threaded_usage() {
             addr = rx.recv().expect("Receiving store address failed");
             let mut pool_access = shared_clone.write().unwrap();
             let pg = PoolGuard::new(pool_access.deref_mut(), addr);
-            let read_res = pg.read().expect("Reading failed");
-            assert_eq!(read_res, DUMMY_DATA);
+            let mut read_buf: [u8; 4] = [0; 4];
+            let read_bytes = pg.read(&mut read_buf).expect("Reading failed");
+            assert_eq!(read_buf, DUMMY_DATA);
+            assert_eq!(read_bytes, 4);
         }
         let pool_access = shared_clone.read().unwrap();
         assert!(!pool_access.has_element_at(&addr).expect("Invalid address"));

satrs-core/tests/pus_verification.rs

@@ -2,8 +2,7 @@
 pub mod crossbeam_test {
     use hashbrown::HashMap;
     use satrs_core::pool::{
-        PoolProviderMemInPlace, PoolProviderMemInPlaceWithGuards, StaticMemoryPool,
-        StaticPoolConfig,
+        PoolProvider, PoolProviderWithGuards, StaticMemoryPool, StaticPoolConfig,
     };
     use satrs_core::pus::verification::{
         FailParams, RequestId, VerificationReporterCfg, VerificationReporterWithSender,
@@ -36,7 +35,8 @@ pub mod crossbeam_test {
         // each reporter have an own sequence count provider.
         let cfg = VerificationReporterCfg::new(TEST_APID, 1, 2, 8).unwrap();
         // Shared pool object to store the verification PUS telemetry
-        let pool_cfg = StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)]);
+        let pool_cfg =
+            StaticPoolConfig::new(vec![(10, 32), (10, 64), (10, 128), (10, 1024)], false);
         let shared_tm_pool = SharedTmPool::new(StaticMemoryPool::new(pool_cfg.clone()));
         let shared_tc_pool_0 = Arc::new(RwLock::new(StaticMemoryPool::new(pool_cfg)));
         let shared_tc_pool_1 = shared_tc_pool_0.clone();
@@ -59,15 +59,21 @@ pub mod crossbeam_test {
             let tc_header = PusTcSecondaryHeader::new_simple(17, 1);
             let pus_tc_0 = PusTcCreator::new_no_app_data(&mut sph, tc_header, true);
             req_id_0 = RequestId::new(&pus_tc_0);
-            let (addr, buf) = tc_guard.free_element(pus_tc_0.len_written()).unwrap();
-            pus_tc_0.write_to_bytes(buf).unwrap();
+            let addr = tc_guard
+                .free_element(pus_tc_0.len_written(), |buf| {
+                    pus_tc_0.write_to_bytes(buf).unwrap();
+                })
+                .unwrap();
             tx_tc_0.send(addr).unwrap();
             let mut sph = SpHeader::tc_unseg(TEST_APID, 1, 0).unwrap();
             let tc_header = PusTcSecondaryHeader::new_simple(5, 1);
             let pus_tc_1 = PusTcCreator::new_no_app_data(&mut sph, tc_header, true);
             req_id_1 = RequestId::new(&pus_tc_1);
-            let (addr, buf) = tc_guard.free_element(pus_tc_0.len_written()).unwrap();
-            pus_tc_1.write_to_bytes(buf).unwrap();
+            let addr = tc_guard
+                .free_element(pus_tc_0.len_written(), |buf| {
+                    pus_tc_1.write_to_bytes(buf).unwrap();
+                })
+                .unwrap();
             tx_tc_1.send(addr).unwrap();
         }
         let verif_sender_0 = thread::spawn(move || {
@@ -79,9 +85,7 @@ pub mod crossbeam_test {
             {
                 let mut tc_guard = shared_tc_pool_0.write().unwrap();
                 let pg = tc_guard.read_with_guard(tc_addr);
-                let buf = pg.read().unwrap();
-                tc_len = buf.len();
-                tc_buf[0..tc_len].copy_from_slice(buf);
+                tc_len = pg.read(&mut tc_buf).unwrap();
             }
             let (_tc, _) = PusTcReader::new(&tc_buf[0..tc_len]).unwrap();
 
@@ -117,9 +121,7 @@ pub mod crossbeam_test {
             {
                 let mut tc_guard = shared_tc_pool_1.write().unwrap();
                 let pg = tc_guard.read_with_guard(tc_addr);
-                let buf = pg.read().unwrap();
-                tc_len = buf.len();
-                tc_buf[0..tc_len].copy_from_slice(buf);
+                tc_len = pg.read(&mut tc_buf).unwrap();
             }
             let (tc, _) = PusTcReader::new(&tc_buf[0..tc_len]).unwrap();
             let token = reporter_with_sender_1.add_tc(&tc);
@@ -149,9 +151,9 @@ pub mod crossbeam_test {
                 {
                     let mut rg = shared_tm_store.write().expect("Error locking shared pool");
                     let store_guard = rg.read_with_guard(verif_addr);
-                    let slice = store_guard.read().expect("Error reading TM slice");
-                    tm_len = slice.len();
-                    tm_buf[0..tm_len].copy_from_slice(slice);
+                    tm_len = store_guard
+                        .read(&mut tm_buf)
+                        .expect("Error reading TM slice");
                 }
                 let (pus_tm, _) =
                     PusTmReader::new(&tm_buf[0..tm_len], 7).expect("Error reading verification TM");

satrs-example/src/config.rs

@@ -103,34 +103,43 @@ pub mod pool {
     use super::*;
     pub fn create_static_pools() -> (StaticMemoryPool, StaticMemoryPool) {
         (
-            StaticMemoryPool::new(StaticPoolConfig::new(vec![
-                (30, 32),
-                (15, 64),
-                (15, 128),
-                (15, 256),
-                (15, 1024),
-                (15, 2048),
-            ])),
-            StaticMemoryPool::new(StaticPoolConfig::new(vec![
-                (30, 32),
-                (15, 64),
-                (15, 128),
-                (15, 256),
-                (15, 1024),
-                (15, 2048),
-            ])),
+            StaticMemoryPool::new(StaticPoolConfig::new(
+                vec![
+                    (30, 32),
+                    (15, 64),
+                    (15, 128),
+                    (15, 256),
+                    (15, 1024),
+                    (15, 2048),
+                ],
+                true,
+            )),
+            StaticMemoryPool::new(StaticPoolConfig::new(
+                vec![
+                    (30, 32),
+                    (15, 64),
+                    (15, 128),
+                    (15, 256),
+                    (15, 1024),
+                    (15, 2048),
+                ],
+                true,
+            )),
         )
     }
 
     pub fn create_sched_tc_pool() -> StaticMemoryPool {
-        StaticMemoryPool::new(StaticPoolConfig::new(vec![
-            (30, 32),
-            (15, 64),
-            (15, 128),
-            (15, 256),
-            (15, 1024),
-            (15, 2048),
-        ]))
+        StaticMemoryPool::new(StaticPoolConfig::new(
+            vec![
+                (30, 32),
+                (15, 64),
+                (15, 128),
+                (15, 256),
+                (15, 1024),
+                (15, 2048),
+            ],
+            true,
+        ))
     }
 }
 

satrs-example/src/pus/scheduler.rs

@@ -2,7 +2,7 @@ use std::sync::mpsc;
 use std::time::Duration;
 
 use log::{error, info, warn};
-use satrs_core::pool::{PoolProviderMemInPlace, StaticMemoryPool, StoreAddr};
+use satrs_core::pool::{PoolProvider, StaticMemoryPool, StoreAddr};
 use satrs_core::pus::scheduler::{PusScheduler, TcInfo};
 use satrs_core::pus::scheduler_srv::PusService11SchedHandler;
 use satrs_core::pus::verification::VerificationReporterWithSender;
@@ -54,6 +54,7 @@ impl TcReleaser for mpsc::Sender<Vec<u8>> {
 pub struct Pus11Wrapper<TcInMemConverter: EcssTcInMemConverter> {
     pub pus_11_handler: PusService11SchedHandler<TcInMemConverter, PusScheduler>,
     pub sched_tc_pool: StaticMemoryPool,
+    pub releaser_buf: [u8; 4096],
     pub tc_releaser: Box<dyn TcReleaser + Send>,
 }
 
@@ -70,7 +71,11 @@ impl<TcInMemConverter: EcssTcInMemConverter> Pus11Wrapper<TcInMemConverter> {
         let released_tcs = self
             .pus_11_handler
             .scheduler_mut()
-            .release_telecommands(releaser, &mut self.sched_tc_pool)
+            .release_telecommands_with_buffer(
+                releaser,
+                &mut self.sched_tc_pool,
+                &mut self.releaser_buf,
+            )
             .expect("releasing TCs failed");
         if released_tcs > 0 {
             info!("{released_tcs} TC(s) released from scheduler");
@@ -136,6 +141,7 @@ pub fn create_scheduler_service_static(
     Pus11Wrapper {
         pus_11_handler,
         sched_tc_pool,
+        releaser_buf: [0; 4096],
         tc_releaser: Box::new(tc_releaser),
     }
 }
@@ -172,6 +178,7 @@ pub fn create_scheduler_service_dynamic(
     Pus11Wrapper {
         pus_11_handler,
         sched_tc_pool,
+        releaser_buf: [0; 4096],
         tc_releaser: Box::new(tc_source_sender),
     }
 }

satrs-example/src/tm_funnel.rs

@@ -3,8 +3,9 @@ use std::{
     sync::mpsc::{Receiver, Sender},
 };
 
+use log::info;
 use satrs_core::{
-    pool::{PoolProviderMemInPlace, StoreAddr},
+    pool::{PoolProvider, StoreAddr},
     seq_count::{CcsdsSimpleSeqCountProvider, SequenceCountProviderCore},
     spacepackets::{
         ecss::{tm::PusTmZeroCopyWriter, PusPacket},
@@ -63,9 +64,14 @@ impl TmFunnelCommon {
             *entry += 1;
         }
 
+        Self::packet_printout(&zero_copy_writer);
         // This operation has to come last!
         zero_copy_writer.finish();
     }
+
+    fn packet_printout(tm: &PusTmZeroCopyWriter) {
+        info!("Sending PUS TM[{},{}]", tm.service(), tm.subservice());
+    }
 }
 
 pub struct TmFunnelStatic {
@@ -96,16 +102,21 @@ impl TmFunnelStatic {
             // the CRC.
             let shared_pool = self.shared_tm_store.clone_backing_pool();
             let mut pool_guard = shared_pool.write().expect("Locking TM pool failed");
-            let tm_raw = pool_guard
-                .modify(&addr)
+            let mut tm_copy = Vec::new();
+            pool_guard
+                .modify(&addr, |buf| {
+                    let zero_copy_writer = PusTmZeroCopyWriter::new(buf, MIN_CDS_FIELD_LEN)
+                        .expect("Creating TM zero copy writer failed");
+                    self.common.apply_packet_processing(zero_copy_writer);
+                    tm_copy = buf.to_vec()
+                })
                 .expect("Reading TM from pool failed");
-            let zero_copy_writer = PusTmZeroCopyWriter::new(tm_raw, MIN_CDS_FIELD_LEN)
-                .expect("Creating TM zero copy writer failed");
-            self.common.apply_packet_processing(zero_copy_writer);
             self.tm_server_tx
                 .send(addr)
                 .expect("Sending TM to server failed");
-            self.common.sync_tm_tcp_source.add_tm(tm_raw);
+            // We could also do this step in the update closure, but I'd rather avoid this, could
+            // lead to nested locking.
+            self.common.sync_tm_tcp_source.add_tm(&tm_copy);
         }
     }
 }

satrs-example/src/tmtc.rs

@@ -5,7 +5,7 @@ use std::sync::mpsc::{self, Receiver, SendError, Sender, TryRecvError};
 use thiserror::Error;
 
 use crate::pus::PusReceiver;
-use satrs_core::pool::{PoolProviderMemInPlace, SharedStaticMemoryPool, StoreAddr, StoreError};
+use satrs_core::pool::{PoolProvider, SharedStaticMemoryPool, StoreAddr, StoreError};
 use satrs_core::spacepackets::ecss::tc::PusTcReader;
 use satrs_core::spacepackets::ecss::PusPacket;
 use satrs_core::tmtc::ReceivesCcsdsTc;
@@ -28,8 +28,9 @@ pub struct SharedTcPool {
 impl SharedTcPool {
     pub fn add_pus_tc(&mut self, pus_tc: &PusTcReader) -> Result<StoreAddr, StoreError> {
         let mut pg = self.pool.write().expect("error locking TC store");
-        let (addr, buf) = pg.free_element(pus_tc.len_packed())?;
-        buf[0..pus_tc.len_packed()].copy_from_slice(pus_tc.raw_data());
+        let addr = pg.free_element(pus_tc.len_packed(), |buf| {
+            buf[0..pus_tc.len_packed()].copy_from_slice(pus_tc.raw_data());
+        })?;
         Ok(addr)
     }
 }
@@ -125,8 +126,8 @@ impl TcSourceTaskStatic {
                     .pool
                     .read()
                     .expect("locking tc pool failed");
-                let data = pool.read(&addr).expect("reading pool failed");
-                self.tc_buf[0..data.len()].copy_from_slice(data);
+                pool.read(&addr, &mut self.tc_buf)
+                    .expect("reading pool failed");
                 drop(pool);
                 match PusTcReader::new(&self.tc_buf) {
                     Ok((pus_tc, _)) => {

satrs-example/src/udp.rs

@@ -6,7 +6,7 @@ use std::{
 use log::{info, warn};
 use satrs_core::{
     hal::std::udp_server::{ReceiveResult, UdpTcServer},
-    pool::{PoolProviderMemInPlaceWithGuards, SharedStaticMemoryPool, StoreAddr},
+    pool::{PoolProviderWithGuards, SharedStaticMemoryPool, StoreAddr},
     tmtc::CcsdsError,
 };
 
@@ -29,20 +29,13 @@ impl UdpTmHandler for StaticUdpTmHandler {
             }
             let mut store_lock = store_lock.unwrap();
             let pg = store_lock.read_with_guard(addr);
-            let read_res = pg.read();
+            let read_res = pg.read_as_vec();
             if read_res.is_err() {
                 warn!("Error reading TM pool data");
                 continue;
             }
             let buf = read_res.unwrap();
-            if buf.len() > 9 {
-                let service = buf[7];
-                let subservice = buf[8];
-                info!("Sending PUS TM[{service},{subservice}]")
-            } else {
-                info!("Sending PUS TM");
-            }
-            let result = socket.send_to(buf, recv_addr);
+            let result = socket.send_to(&buf, recv_addr);
             if let Err(e) = result {
                 warn!("Sending TM with UDP socket failed: {e}")
             }