treewide: use thiserror

I think this makes the code a little nicer.

Author: phip1611

Cargo.lock

@@ -14,11 +14,14 @@ package.license = "MIT/Apache-2.0"
 
 [workspace.dependencies]
 bitflags = "2.9.1"
-derive_more = { version = "2.0.1", default-features = false, features = ["display"] }
 log = { version = "~0.4", default-features = false }
+ptr_meta = { version = "~0.3", default-features = false, features = ["derive"] }
+thiserror = { version = "2.0.12", default-features = false }
+
+# Intra-workspace dependencies of upstream crates: always point to the latest
+# stable version
 multiboot2 = { version = "0.23.1", default-features = false }
 multiboot2-common = { version = "0.2.1", default-features = false }
-ptr_meta = { version = "~0.3", default-features = false, features = ["derive"] }
 
 # This way, the corresponding crate dependency can be normalley referenced by
 # version, while still the repository version is used transparently during local

Cargo.toml

@@ -29,8 +29,8 @@ builder = ["alloc"]
 
 
 [dependencies]
-derive_more.workspace = true
 ptr_meta.workspace = true
+thiserror.workspace = true
 
 [package.metadata.docs.rs]
 all-features = true

multiboot2-common/Cargo.toml

@@ -260,6 +260,7 @@ use core::mem;
 use core::ptr;
 use core::ptr::NonNull;
 use core::slice;
+use thiserror::Error;
 
 /// The alignment of all Multiboot2 data structures.
 pub const ALIGNMENT: usize = 8;
@@ -423,26 +424,29 @@ impl<H: Header> DynSizedStructure<H> {
 }
 
 /// Errors that may occur when working with memory.
-#[derive(Copy, Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Hash, derive_more::Display)]
+#[derive(Copy, Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Hash, Error)]
 pub enum MemoryError {
     /// The memory points to null.
+    #[error("memory points to null")]
     Null,
     /// The memory must be at least [`ALIGNMENT`]-aligned.
+    #[error("memory is not properly aligned")]
     WrongAlignment,
     /// The memory must cover at least the length of the sized structure header
     /// type.
+    #[error("memory range is shorter than the size of the header structure")]
     ShorterThanHeader,
     /// The buffer misses the terminating padding to the next alignment
     /// boundary. The padding is relevant to satisfy Rustc/Miri, but also the
     /// spec mandates that the padding is added.
+    #[error("memory is missing required padding")]
     MissingPadding,
     /// The size-property has an illegal value that can't be fulfilled with the
     /// given bytes.
+    #[error("the header reports an invalid total size")]
     InvalidReportedTotalSize,
 }
 
-impl core::error::Error for MemoryError {}
-
 /// Increases the given size to the next alignment boundary, if it is not a
 /// multiple of the alignment yet.
 ///

multiboot2-common/src/lib.rs

@@ -41,11 +41,11 @@ alloc = ["multiboot2-common/alloc"]
 builder = ["alloc", "multiboot2-common/builder"]
 
 [dependencies]
-derive_more.workspace = true
 log.workspace = true
 multiboot2-common.workspace = true
 multiboot2.workspace = true
 ptr_meta.workspace = true
+thiserror.workspace = true
 
 [package.metadata.docs.rs]
 all-features = true

multiboot2-header/Cargo.toml

@@ -7,7 +7,8 @@ use crate::{
 use core::fmt::{Debug, Formatter};
 use core::mem::size_of;
 use core::ptr::NonNull;
-use multiboot2_common::{DynSizedStructure, Header, MemoryError, Tag, ALIGNMENT};
+use multiboot2_common::{ALIGNMENT, DynSizedStructure, Header, MemoryError, Tag};
+use thiserror::Error;
 
 /// Magic value for a [`Multiboot2Header`], as defined by the spec.
 pub const MAGIC: u32 = 0xe85250d6;
@@ -224,24 +225,18 @@ impl Debug for Multiboot2Header<'_> {
 
 /// Errors that occur when a chunk of memory can't be parsed as
 /// [`Multiboot2Header`].
-#[derive(Copy, Clone, Debug, derive_more::Display, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Error)]
 pub enum LoadError {
     /// The provided checksum does not match the expected value.
+    #[error("checksum does not match expected value")]
     ChecksumMismatch,
     /// The header does not contain the correct magic number.
+    #[error("header does not contain expected magic value")]
     MagicNotFound,
     /// The provided memory can't be parsed as [`Multiboot2Header`].
     /// See [`MemoryError`].
-    Memory(MemoryError),
-}
-
-impl Error for LoadError {
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        match self {
-            Self::Memory(inner) => Some(inner),
-            _ => None,
-        }
-    }
+    #[error("memory can't be parsed as multiboot2 header")]
+    Memory(#[source] MemoryError),
 }
 
 /// The "basic" Multiboot2 header. This means only the properties, that are known during

multiboot2-header/src/header.rs

@@ -41,10 +41,10 @@ builder = ["alloc", "multiboot2-common/builder"]
 
 [dependencies]
 bitflags.workspace = true
-derive_more.workspace = true
 log.workspace = true
-ptr_meta.workspace = true
 multiboot2-common.workspace = true
+ptr_meta.workspace = true
+thiserror.workspace = true
 uefi-raw = { version = "~0.8.0", default-features = false }
 
 [package.metadata.docs.rs]

multiboot2/Cargo.toml

@@ -3,39 +3,31 @@
 use crate::framebuffer::UnknownFramebufferType;
 use crate::tag::TagHeader;
 use crate::{
-    module, ApmTag, BasicMemoryInfoTag, BootLoaderNameTag, BootdevTag, CommandLineTag,
+    ApmTag, BasicMemoryInfoTag, BootLoaderNameTag, BootdevTag, CommandLineTag,
     EFIBootServicesNotExitedTag, EFIImageHandle32Tag, EFIImageHandle64Tag, EFIMemoryMapTag,
     EFISdt32Tag, EFISdt64Tag, ElfSectionIter, ElfSectionsTag, EndTag, FramebufferTag,
     ImageLoadPhysAddrTag, MemoryMapTag, ModuleIter, NetworkTag, RsdpV1Tag, RsdpV2Tag, SmbiosTag,
-    TagIter, TagType, VBEInfoTag,
+    TagIter, TagType, VBEInfoTag, module,
 };
-use core::error::Error;
 use core::fmt;
 use core::mem;
 use core::ptr::NonNull;
-use derive_more::Display;
 use multiboot2_common::{DynSizedStructure, Header, MaybeDynSized, MemoryError, Tag};
+use thiserror::Error;
 
 /// Errors that occur when a chunk of memory can't be parsed as
 /// [`BootInformation`].
-#[derive(Display, Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Error)]
 pub enum LoadError {
     /// The provided memory can't be parsed as [`BootInformation`].
     /// See [`MemoryError`].
-    Memory(MemoryError),
+    #[error("memory can't be parsed as boot information")]
+    Memory(#[source] MemoryError),
     /// Missing mandatory end tag.
+    #[error("missing mandatory end tag")]
     NoEndTag,
 }
 
-impl Error for LoadError {
-    fn source(&self) -> Option<&(dyn Error + 'static)> {
-        match self {
-            Self::Memory(inner) => Some(inner),
-            Self::NoEndTag => None,
-        }
-    }
-}
-
 /// The basic header of a [`BootInformation`] as sized Rust type.
 #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[repr(C, align(8))]

multiboot2/src/boot_information.rs

@@ -1,12 +1,12 @@
 //! Module for [`FramebufferTag`].
 
-use crate::tag::TagHeader;
 use crate::TagType;
+use crate::tag::TagHeader;
 use core::fmt::Debug;
 use core::mem;
 use core::slice;
-use derive_more::Display;
 use multiboot2_common::{MaybeDynSized, Tag};
+use thiserror::Error;
 #[cfg(feature = "builder")]
 use {alloc::boxed::Box, multiboot2_common::new_boxed};
 
@@ -402,12 +402,10 @@ pub struct FramebufferColor {
 }
 
 /// Error when an unknown [`FramebufferTypeId`] is found.
-#[derive(Debug, Copy, Clone, Display, PartialEq, Eq)]
-#[display("Unknown framebuffer type {}", _0)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Error)]
+#[error("Unknown framebuffer type {0}")]
 pub struct UnknownFramebufferType(u8);
 
-impl core::error::Error for UnknownFramebufferType {}
-
 #[cfg(test)]
 mod tests {
     use super::*;

multiboot2/src/framebuffer.rs

@@ -1,7 +1,5 @@
 //! Various utilities.
 
-use core::fmt;
-use core::fmt::{Display, Formatter};
 use core::str::Utf8Error;
 use thiserror::Error;
 
@@ -10,24 +8,11 @@ use thiserror::Error;
 pub enum StringError {
     /// There is no terminating NUL character, although the specification
     /// requires one.
-    MissingNul(core::ffi::FromBytesUntilNulError),
+    #[error("string is not null terminated")]
+    MissingNul(#[source] core::ffi::FromBytesUntilNulError),
     /// The sequence until the first NUL character is not valid UTF-8.
-    Utf8(Utf8Error),
-}
-
-impl Display for StringError {
-    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        write!(f, "{self:?}")
-    }
-}
-
-impl core::error::Error for StringError {
-    fn source(&self) -> Option<&(dyn core::error::Error + 'static)> {
-        match self {
-            Self::MissingNul(e) => Some(e),
-            Self::Utf8(e) => Some(e),
-        }
-    }
+    #[error("string is not valid UTF-8")]
+    Utf8(#[source] Utf8Error),
 }
 
 /// Parses the provided byte sequence as Multiboot string, which maps to a