1 files changed, 364 insertions, 0 deletions
diff --git a/third_party/rust/object/src/read/coff/file.rs b/third_party/rust/object/src/read/coff/file.rs
new file mode 100644
index 0000000000..4219f8f027
--- /dev/null
+++ b/third_party/rust/object/src/read/coff/file.rs
@@ -0,0 +1,364 @@
+use alloc::vec::Vec;
+use core::fmt::Debug;
+
+use crate::read::{
+    self, Architecture, Export, FileFlags, Import, NoDynamicRelocationIterator, Object, ObjectKind,
+    ObjectSection, ReadError, ReadRef, Result, SectionIndex, SymbolIndex,
+};
+use crate::{pe, LittleEndian as LE, Pod};
+
+use super::{
+    CoffComdat, CoffComdatIterator, CoffSection, CoffSectionIterator, CoffSegment,
+    CoffSegmentIterator, CoffSymbol, CoffSymbolIterator, CoffSymbolTable, ImageSymbol,
+    SectionTable, SymbolTable,
+};
+
+/// The common parts of `PeFile` and `CoffFile`.
+#[derive(Debug)]
+pub(crate) struct CoffCommon<'data, R: ReadRef<'data>, Coff: CoffHeader = pe::ImageFileHeader> {
+    pub(crate) sections: SectionTable<'data>,
+    pub(crate) symbols: SymbolTable<'data, R, Coff>,
+    pub(crate) image_base: u64,
+}
+
+/// A COFF bigobj object file with 32-bit section numbers.
+pub type CoffBigFile<'data, R = &'data [u8]> = CoffFile<'data, R, pe::AnonObjectHeaderBigobj>;
+
+/// A COFF object file.
+#[derive(Debug)]
+pub struct CoffFile<'data, R: ReadRef<'data> = &'data [u8], Coff: CoffHeader = pe::ImageFileHeader>
+{
+    pub(super) header: &'data Coff,
+    pub(super) common: CoffCommon<'data, R, Coff>,
+    pub(super) data: R,
+}
+
+impl<'data, R: ReadRef<'data>, Coff: CoffHeader> CoffFile<'data, R, Coff> {
+    /// Parse the raw COFF file data.
+    pub fn parse(data: R) -> Result<Self> {
+        let mut offset = 0;
+        let header = Coff::parse(data, &mut offset)?;
+        let sections = header.sections(data, offset)?;
+        let symbols = header.symbols(data)?;
+
+        Ok(CoffFile {
+            header,
+            common: CoffCommon {
+                sections,
+                symbols,
+                image_base: 0,
+            },
+            data,
+        })
+    }
+}
+
+impl<'data, R: ReadRef<'data>, Coff: CoffHeader> read::private::Sealed
+    for CoffFile<'data, R, Coff>
+{
+}
+
+impl<'data, 'file, R, Coff> Object<'data, 'file> for CoffFile<'data, R, Coff>
+where
+    'data: 'file,
+    R: 'file + ReadRef<'data>,
+    Coff: CoffHeader,
+{
+    type Segment = CoffSegment<'data, 'file, R, Coff>;
+    type SegmentIterator = CoffSegmentIterator<'data, 'file, R, Coff>;
+    type Section = CoffSection<'data, 'file, R, Coff>;
+    type SectionIterator = CoffSectionIterator<'data, 'file, R, Coff>;
+    type Comdat = CoffComdat<'data, 'file, R, Coff>;
+    type ComdatIterator = CoffComdatIterator<'data, 'file, R, Coff>;
+    type Symbol = CoffSymbol<'data, 'file, R, Coff>;
+    type SymbolIterator = CoffSymbolIterator<'data, 'file, R, Coff>;
+    type SymbolTable = CoffSymbolTable<'data, 'file, R, Coff>;
+    type DynamicRelocationIterator = NoDynamicRelocationIterator;
+
+    fn architecture(&self) -> Architecture {
+        match self.header.machine() {
+            pe::IMAGE_FILE_MACHINE_ARMNT => Architecture::Arm,
+            pe::IMAGE_FILE_MACHINE_ARM64 => Architecture::Aarch64,
+            pe::IMAGE_FILE_MACHINE_I386 => Architecture::I386,
+            pe::IMAGE_FILE_MACHINE_AMD64 => Architecture::X86_64,
+            _ => Architecture::Unknown,
+        }
+    }
+
+    #[inline]
+    fn is_little_endian(&self) -> bool {
+        true
+    }
+
+    #[inline]
+    fn is_64(&self) -> bool {
+        // Windows COFF is always 32-bit, even for 64-bit architectures. This could be confusing.
+        false
+    }
+
+    fn kind(&self) -> ObjectKind {
+        ObjectKind::Relocatable
+    }
+
+    fn segments(&'file self) -> CoffSegmentIterator<'data, 'file, R, Coff> {
+        CoffSegmentIterator {
+            file: self,
+            iter: self.common.sections.iter(),
+        }
+    }
+
+    fn section_by_name_bytes(
+        &'file self,
+        section_name: &[u8],
+    ) -> Option<CoffSection<'data, 'file, R, Coff>> {
+        self.sections()
+            .find(|section| section.name_bytes() == Ok(section_name))
+    }
+
+    fn section_by_index(
+        &'file self,
+        index: SectionIndex,
+    ) -> Result<CoffSection<'data, 'file, R, Coff>> {
+        let section = self.common.sections.section(index.0)?;
+        Ok(CoffSection {
+            file: self,
+            index,
+            section,
+        })
+    }
+
+    fn sections(&'file self) -> CoffSectionIterator<'data, 'file, R, Coff> {
+        CoffSectionIterator {
+            file: self,
+            iter: self.common.sections.iter().enumerate(),
+        }
+    }
+
+    fn comdats(&'file self) -> CoffComdatIterator<'data, 'file, R, Coff> {
+        CoffComdatIterator {
+            file: self,
+            index: 0,
+        }
+    }
+
+    fn symbol_by_index(
+        &'file self,
+        index: SymbolIndex,
+    ) -> Result<CoffSymbol<'data, 'file, R, Coff>> {
+        let symbol = self.common.symbols.symbol(index.0)?;
+        Ok(CoffSymbol {
+            file: &self.common,
+            index,
+            symbol,
+        })
+    }
+
+    fn symbols(&'file self) -> CoffSymbolIterator<'data, 'file, R, Coff> {
+        CoffSymbolIterator {
+            file: &self.common,
+            index: 0,
+        }
+    }
+
+    #[inline]
+    fn symbol_table(&'file self) -> Option<CoffSymbolTable<'data, 'file, R, Coff>> {
+        Some(CoffSymbolTable { file: &self.common })
+    }
+
+    fn dynamic_symbols(&'file self) -> CoffSymbolIterator<'data, 'file, R, Coff> {
+        CoffSymbolIterator {
+            file: &self.common,
+            // Hack: don't return any.
+            index: self.common.symbols.len(),
+        }
+    }
+
+    #[inline]
+    fn dynamic_symbol_table(&'file self) -> Option<CoffSymbolTable<'data, 'file, R, Coff>> {
+        None
+    }
+
+    #[inline]
+    fn dynamic_relocations(&'file self) -> Option<NoDynamicRelocationIterator> {
+        None
+    }
+
+    #[inline]
+    fn imports(&self) -> Result<Vec<Import<'data>>> {
+        // TODO: this could return undefined symbols, but not needed yet.
+        Ok(Vec::new())
+    }
+
+    #[inline]
+    fn exports(&self) -> Result<Vec<Export<'data>>> {
+        // TODO: this could return global symbols, but not needed yet.
+        Ok(Vec::new())
+    }
+
+    fn has_debug_symbols(&self) -> bool {
+        self.section_by_name(".debug_info").is_some()
+    }
+
+    fn relative_address_base(&self) -> u64 {
+        0
+    }
+
+    #[inline]
+    fn entry(&self) -> u64 {
+        0
+    }
+
+    fn flags(&self) -> FileFlags {
+        FileFlags::Coff {
+            characteristics: self.header.characteristics(),
+        }
+    }
+}
+
+/// Read the `class_id` field from an anon object header.
+///
+/// This can be used to determine the format of the header.
+pub fn anon_object_class_id<'data, R: ReadRef<'data>>(data: R) -> Result<pe::ClsId> {
+    let header = data
+        .read_at::<pe::AnonObjectHeader>(0)
+        .read_error("Invalid anon object header size or alignment")?;
+    Ok(header.class_id)
+}
+
+/// A trait for generic access to `ImageFileHeader` and `AnonObjectHeaderBigobj`.
+#[allow(missing_docs)]
+pub trait CoffHeader: Debug + Pod {
+    type ImageSymbol: ImageSymbol;
+    type ImageSymbolBytes: Debug + Pod;
+
+    /// Return true if this type is `AnonObjectHeaderBigobj`.
+    ///
+    /// This is a property of the type, not a value in the header data.
+    fn is_type_bigobj() -> bool;
+
+    fn machine(&self) -> u16;
+    fn number_of_sections(&self) -> u32;
+    fn pointer_to_symbol_table(&self) -> u32;
+    fn number_of_symbols(&self) -> u32;
+    fn characteristics(&self) -> u16;
+
+    /// Read the file header.
+    ///
+    /// `data` must be the entire file data.
+    /// `offset` must be the file header offset. It is updated to point after the optional header,
+    /// which is where the section headers are located.
+    fn parse<'data, R: ReadRef<'data>>(data: R, offset: &mut u64) -> read::Result<&'data Self>;
+
+    /// Read the section table.
+    ///
+    /// `data` must be the entire file data.
+    /// `offset` must be after the optional file header.
+    #[inline]
+    fn sections<'data, R: ReadRef<'data>>(
+        &self,
+        data: R,
+        offset: u64,
+    ) -> read::Result<SectionTable<'data>> {
+        SectionTable::parse(self, data, offset)
+    }
+
+    /// Read the symbol table and string table.
+    ///
+    /// `data` must be the entire file data.
+    #[inline]
+    fn symbols<'data, R: ReadRef<'data>>(
+        &self,
+        data: R,
+    ) -> read::Result<SymbolTable<'data, R, Self>> {
+        SymbolTable::parse(self, data)
+    }
+}
+
+impl CoffHeader for pe::ImageFileHeader {
+    type ImageSymbol = pe::ImageSymbol;
+    type ImageSymbolBytes = pe::ImageSymbolBytes;
+
+    fn is_type_bigobj() -> bool {
+        false
+    }
+
+    fn machine(&self) -> u16 {
+        self.machine.get(LE)
+    }
+
+    fn number_of_sections(&self) -> u32 {
+        self.number_of_sections.get(LE).into()
+    }
+
+    fn pointer_to_symbol_table(&self) -> u32 {
+        self.pointer_to_symbol_table.get(LE)
+    }
+
+    fn number_of_symbols(&self) -> u32 {
+        self.number_of_symbols.get(LE)
+    }
+
+    fn characteristics(&self) -> u16 {
+        self.characteristics.get(LE)
+    }
+
+    fn parse<'data, R: ReadRef<'data>>(data: R, offset: &mut u64) -> read::Result<&'data Self> {
+        let header = data
+            .read::<pe::ImageFileHeader>(offset)
+            .read_error("Invalid COFF file header size or alignment")?;
+
+        // Skip over the optional header.
+        *offset = offset
+            .checked_add(header.size_of_optional_header.get(LE).into())
+            .read_error("Invalid COFF optional header size")?;
+
+        // TODO: maybe validate that the machine is known?
+        Ok(header)
+    }
+}
+
+impl CoffHeader for pe::AnonObjectHeaderBigobj {
+    type ImageSymbol = pe::ImageSymbolEx;
+    type ImageSymbolBytes = pe::ImageSymbolExBytes;
+
+    fn is_type_bigobj() -> bool {
+        true
+    }
+
+    fn machine(&self) -> u16 {
+        self.machine.get(LE)
+    }
+
+    fn number_of_sections(&self) -> u32 {
+        self.number_of_sections.get(LE)
+    }
+
+    fn pointer_to_symbol_table(&self) -> u32 {
+        self.pointer_to_symbol_table.get(LE)
+    }
+
+    fn number_of_symbols(&self) -> u32 {
+        self.number_of_symbols.get(LE)
+    }
+
+    fn characteristics(&self) -> u16 {
+        0
+    }
+
+    fn parse<'data, R: ReadRef<'data>>(data: R, offset: &mut u64) -> read::Result<&'data Self> {
+        let header = data
+            .read::<pe::AnonObjectHeaderBigobj>(offset)
+            .read_error("Invalid COFF bigobj file header size or alignment")?;
+
+        if header.sig1.get(LE) != pe::IMAGE_FILE_MACHINE_UNKNOWN
+            || header.sig2.get(LE) != 0xffff
+            || header.version.get(LE) < 2
+            || header.class_id != pe::ANON_OBJECT_HEADER_BIGOBJ_CLASS_ID
+        {
+            return Err(read::Error("Invalid COFF bigobj header values"));
+        }
+
+        // TODO: maybe validate that the machine is known?
+        Ok(header)
+    }
+}