bump embedded-io to v0.7 and introduce thiserror

CHANGELOG.md

@@ -17,13 +17,15 @@ The format is based on [Keep a Changelog] and this project adheres to [Semantic
 - Added `open_long_name_file_in_dir` API, to open files using their Long File Name
 - Updated directory iterator callback, to allow bailing out early (breaking change)
 - `crc7` function now returns the actual CRC7 value without left-shifting by and XOR-ing by/with 1.
+- Bumped `embedded-io` to 0.7
 
 ### Added
 
 - Added `CsdV3` data structure.
 - `Csd::new` constructor which creates the CSD from a raw `&[u8; 16]` and also performs a CRC7
   check.
 - Added `verify_crc7` function on CSD structures.
+- Added `core::error::Error` bounds to device driver error type
 
 ## [Version 0.9.0] - 2025-06-08
 

Cargo.toml

@@ -17,7 +17,7 @@ rust-version = "1.87"
 byteorder = {version = "1", default-features = false}
 defmt = {version = "1.0.1", optional = true}
 embedded-hal = "1.0.0"
-embedded-io = "0.6.1"
+embedded-io = "0.7"
 bitbybit = "2"
 arbitrary-int = "2"
 bitflags = "2"

src/blockdevice.rs

@@ -77,7 +77,7 @@ impl Default for Block {
 /// sectors). Only supports devices which are <= 2 TiB in size.
 pub trait BlockDevice {
     /// The errors that the `BlockDevice` can return. Must be debug formattable.
-    type Error: core::fmt::Debug;
+    type Error: core::error::Error + 'static;
     /// Read one or more blocks, starting at the given block index.
     fn read(&self, blocks: &mut [Block], start_block_idx: BlockIdx) -> Result<(), Self::Error>;
     /// Write one or more blocks, starting at the given block index.

src/lib.rs

@@ -158,77 +158,107 @@ macro_rules! warn {
 
 /// All the ways the functions in this crate can fail.
 #[cfg_attr(feature = "defmt-log", derive(defmt::Format))]
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, thiserror::Error)]
 pub enum Error<E>
 where
-    E: core::fmt::Debug,
+    E: core::error::Error,
 {
     /// The underlying block device threw an error.
-    DeviceError(E),
+    #[error("error from underlying block device: {0}")]
+    DeviceError(#[from] E),
     /// The filesystem is badly formatted (or this code is buggy).
+    #[error("filesystem is badly formatted: {0}")]
     FormatError(&'static str),
     /// The given `VolumeIdx` was bad,
+    #[error("no such volume")]
     NoSuchVolume,
     /// The given filename was bad
+    #[error("bad filename")]
     FilenameError(FilenameError),
     /// Out of memory opening volumes
+    #[error("too many open volumes")]
     TooManyOpenVolumes,
     /// Out of memory opening directories
+    #[error("too many open directories")]
     TooManyOpenDirs,
     /// Out of memory opening files
+    #[error("too many open files")]
     TooManyOpenFiles,
     /// Bad handle given
+    #[error("bad handle")]
     BadHandle,
     /// That file or directory doesn't exist
+    #[error("file or directory does not exist")]
     NotFound,
     /// You can't open a file twice or delete an open file
+    #[error("file already open")]
     FileAlreadyOpen,
     /// You can't open a directory twice
+    #[error("directory already open")]
     DirAlreadyOpen,
     /// You can't open a directory as a file
+    #[error("cannot open directory as file")]
     OpenedDirAsFile,
     /// You can't open a file as a directory
+    #[error("cannot open file as directory")]
     OpenedFileAsDir,
     /// You can't delete a non-empty directory
+    #[error("cannot delete a non-empty directory")]
     DeleteNonEmptyDir,
     /// You can't close a volume with open files or directories
+    #[error("volume is still in use")]
     VolumeStillInUse,
     /// You can't open a volume twice
+    #[error("cannot open volume twice")]
     VolumeAlreadyOpen,
     /// We can't do that yet
+    #[error("unsupported operation")]
     Unsupported,
     /// Tried to read beyond end of file
+    #[error("end of file")]
     EndOfFile,
     /// Found a bad cluster
+    #[error("bad cluster")]
     BadCluster,
     /// Error while converting types
+    #[error("type conversion failed")]
     ConversionError,
     /// The device does not have enough space for the operation
+    #[error("not enough space on device")]
     NotEnoughSpace,
     /// Cluster was not properly allocated by the library
+    #[error("cluster not properly allocated")]
     AllocationError,
     /// Jumped to free space during FAT traversing
+    #[error("FAT chain unterminated")]
     UnterminatedFatChain,
     /// Tried to open Read-Only file with write mode
+    #[error("file is read-only")]
     ReadOnly,
     /// Tried to create an existing file
+    #[error("file already exists")]
     FileAlreadyExists,
     /// Bad block size - only 512 byte blocks supported
+    #[error("bad block size: {0} (only 512 byte blocks supported)")]
     BadBlockSize(u16),
     /// Bad offset given when seeking
+    #[error("invalid seek offset")]
     InvalidOffset,
     /// Disk is full
+    #[error("disk full")]
     DiskFull,
     /// A directory with that name already exists
+    #[error("directory already exists")]
     DirAlreadyExists,
     /// The filesystem tried to gain a lock whilst already locked.
     ///
     /// This is either a bug in the filesystem, or you tried to access the
     /// filesystem API from inside a directory iterator (that isn't allowed).
+    #[error("already locked")]
     LockError,
 }
 
-impl<E: Debug> embedded_io::Error for Error<E> {
+impl<E: core::error::Error + 'static> embedded_io::Error for Error<E> {
     fn kind(&self) -> ErrorKind {
         match self {
             Error::DeviceError(_)
@@ -263,59 +293,6 @@ impl<E: Debug> embedded_io::Error for Error<E> {
     }
 }
 
-impl<E> From<E> for Error<E>
-where
-    E: core::fmt::Debug,
-{
-    fn from(value: E) -> Error<E> {
-        Error::DeviceError(value)
-    }
-}
-
-impl<E> core::fmt::Display for Error<E>
-where
-    E: core::fmt::Debug + core::fmt::Display,
-{
-    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
-        match self {
-            Error::DeviceError(e) => write!(f, "error from underlying block device: {e}"),
-            Error::FormatError(s) => write!(f, "filesystem is badly formatted: {s}"),
-            Error::NoSuchVolume => write!(f, "no such volume"),
-            Error::FilenameError(_) => write!(f, "bad filename"),
-            Error::TooManyOpenVolumes => write!(f, "too many open volumes"),
-            Error::TooManyOpenDirs => write!(f, "too many open directories"),
-            Error::TooManyOpenFiles => write!(f, "too many open files"),
-            Error::BadHandle => write!(f, "bad handle"),
-            Error::NotFound => write!(f, "file or directory does not exist"),
-            Error::FileAlreadyOpen => write!(f, "file already open"),
-            Error::DirAlreadyOpen => write!(f, "directory already open"),
-            Error::OpenedDirAsFile => write!(f, "cannot open directory as file"),
-            Error::OpenedFileAsDir => write!(f, "cannot open file as directory"),
-            Error::DeleteNonEmptyDir => write!(f, "cannot delete a non-empty directory"),
-            Error::VolumeStillInUse => write!(f, "volume is still in use"),
-            Error::VolumeAlreadyOpen => write!(f, "cannot open volume twice"),
-            Error::Unsupported => write!(f, "unsupported operation"),
-            Error::EndOfFile => write!(f, "end of file"),
-            Error::BadCluster => write!(f, "bad cluster"),
-            Error::ConversionError => write!(f, "type conversion failed"),
-            Error::NotEnoughSpace => write!(f, "not enough space on device"),
-            Error::AllocationError => write!(f, "cluster not properly allocated"),
-            Error::UnterminatedFatChain => write!(f, "FAT chain unterminated"),
-            Error::ReadOnly => write!(f, "file is read-only"),
-            Error::FileAlreadyExists => write!(f, "file already exists"),
-            Error::BadBlockSize(size) => {
-                write!(f, "bad block size: {size} (only 512 byte blocks supported)")
-            }
-            Error::InvalidOffset => write!(f, "invalid seek offset"),
-            Error::DiskFull => write!(f, "disk full"),
-            Error::DirAlreadyExists => write!(f, "directory already exists"),
-            Error::LockError => write!(f, "already locked"),
-        }
-    }
-}
-
-impl<E> core::error::Error for Error<E> where E: core::fmt::Debug + core::fmt::Display {}
-
 /// A handle to a volume.
 ///
 /// A volume is a partition with a filesystem within it.

src/volume_mgr.rs

@@ -36,7 +36,6 @@ pub struct VolumeManager<
 > where
     D: BlockDevice,
     T: TimeSource,
-    <D as BlockDevice>::Error: core::fmt::Debug,
 {
     time_source: T,
     data: RefCell<VolumeManagerData<D, MAX_DIRS, MAX_FILES, MAX_VOLUMES>>,
@@ -46,7 +45,6 @@ impl<D, T> VolumeManager<D, T, 4, 4>
 where
     D: BlockDevice,
     T: TimeSource,
-    <D as BlockDevice>::Error: core::fmt::Debug,
 {
     /// Create a new Volume Manager using a generic `BlockDevice`. From this
     /// object we can open volumes (partitions) and with those we can open
@@ -67,7 +65,6 @@ impl<D, T, const MAX_DIRS: usize, const MAX_FILES: usize, const MAX_VOLUMES: usi
 where
     D: BlockDevice,
     T: TimeSource,
-    <D as BlockDevice>::Error: core::fmt::Debug,
 {
     /// Create a new Volume Manager using a generic `BlockDevice`. From this
     /// object we can open volumes (partitions) and with those we can open
@@ -1430,6 +1427,7 @@ impl<D, const MAX_DIRS: usize, const MAX_FILES: usize, const MAX_VOLUMES: usize>
     VolumeManagerData<D, MAX_DIRS, MAX_FILES, MAX_VOLUMES>
 where
     D: BlockDevice,
+    <D as BlockDevice>::Error: core::error::Error,
 {
     /// Check if a file is open
     ///
@@ -1446,10 +1444,10 @@ where
         false
     }
 
-    fn get_volume_by_id<E>(&self, raw_volume: RawVolume) -> Result<usize, Error<E>>
-    where
-        E: core::fmt::Debug,
-    {
+    fn get_volume_by_id<E: core::error::Error>(
+        &self,
+        raw_volume: RawVolume,
+    ) -> Result<usize, Error<E>> {
         for (idx, v) in self.open_volumes.iter().enumerate() {
             if v.raw_volume == raw_volume {
                 return Ok(idx);
@@ -1458,10 +1456,10 @@ where
         Err(Error::BadHandle)
     }
 
-    fn get_dir_by_id<E>(&self, raw_directory: RawDirectory) -> Result<usize, Error<E>>
-    where
-        E: core::fmt::Debug,
-    {
+    fn get_dir_by_id<E: core::error::Error>(
+        &self,
+        raw_directory: RawDirectory,
+    ) -> Result<usize, Error<E>> {
         for (idx, d) in self.open_dirs.iter().enumerate() {
             if d.raw_directory == raw_directory {
                 return Ok(idx);
@@ -1470,10 +1468,7 @@ where
         Err(Error::BadHandle)
     }
 
-    fn get_file_by_id<E>(&self, raw_file: RawFile) -> Result<usize, Error<E>>
-    where
-        E: core::fmt::Debug,
-    {
+    fn get_file_by_id<E: core::error::Error>(&self, raw_file: RawFile) -> Result<usize, Error<E>> {
         for (idx, f) in self.open_files.iter().enumerate() {
             if f.raw_file == raw_file {
                 return Ok(idx);
@@ -1570,8 +1565,9 @@ mod tests {
 
     struct Clock;
 
-    #[derive(Debug)]
+    #[derive(Debug, thiserror::Error)]
     enum Error {
+        #[error("unknown error")]
         Unknown,
     }
 

tests/utils/mod.rs

@@ -40,29 +40,20 @@ use embedded_sdmmc::{Block, BlockCount, BlockDevice, BlockIdx};
 /// It will unpack to a Vec that is 1048576 * 512 = 512 MiB in size.
 pub static DISK_SOURCE: &[u8] = include_bytes!("../disk.img.gz");
 
-#[derive(Debug)]
+#[derive(Debug, thiserror::Error)]
 #[allow(dead_code)]
 pub enum Error {
     /// Failed to read the source image
-    Io(std::io::Error),
+    #[error("I/O error: {0}")]
+    Io(#[from] std::io::Error),
     /// Failed to unzip the source image
-    Decode(flate2::DecompressError),
+    #[error("flate2 decode error: {0}")]
+    Decode(#[from] flate2::DecompressError),
     /// Asked for a block we don't have
+    #[error("out of bounds block index: {0:?}")]
     OutOfBounds(BlockIdx),
 }
 
-impl From<std::io::Error> for Error {
-    fn from(value: std::io::Error) -> Self {
-        Self::Io(value)
-    }
-}
-
-impl From<flate2::DecompressError> for Error {
-    fn from(value: flate2::DecompressError) -> Self {
-        Self::Decode(value)
-    }
-}
-
 /// Implements the block device traits for a chunk of bytes in RAM.
 ///
 /// The slice should be a multiple of `embedded_sdmmc::Block::LEN` bytes in