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-rw-r--r--third_party/rust/object/src/write/coff.rs713
1 files changed, 713 insertions, 0 deletions
diff --git a/third_party/rust/object/src/write/coff.rs b/third_party/rust/object/src/write/coff.rs
new file mode 100644
index 0000000000..e2d036df88
--- /dev/null
+++ b/third_party/rust/object/src/write/coff.rs
@@ -0,0 +1,713 @@
+use alloc::vec::Vec;
+use core::mem;
+
+use crate::endian::{LittleEndian as LE, U16Bytes, U32Bytes, U16, U32};
+use crate::pe as coff;
+use crate::write::string::*;
+use crate::write::util::*;
+use crate::write::*;
+
+#[derive(Default, Clone, Copy)]
+struct SectionOffsets {
+ offset: usize,
+ str_id: Option<StringId>,
+ reloc_offset: usize,
+ selection: u8,
+ associative_section: u16,
+}
+
+#[derive(Default, Clone, Copy)]
+struct SymbolOffsets {
+ index: usize,
+ str_id: Option<StringId>,
+ aux_count: u8,
+}
+
+/// Internal format to use for the `.drectve` section containing linker
+/// directives for symbol exports.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum CoffExportStyle {
+ /// MSVC format supported by link.exe and LLD.
+ Msvc,
+ /// Gnu format supported by GNU LD and LLD.
+ Gnu,
+}
+
+impl<'a> Object<'a> {
+ pub(crate) fn coff_section_info(
+ &self,
+ section: StandardSection,
+ ) -> (&'static [u8], &'static [u8], SectionKind) {
+ match section {
+ StandardSection::Text => (&[], &b".text"[..], SectionKind::Text),
+ StandardSection::Data => (&[], &b".data"[..], SectionKind::Data),
+ StandardSection::ReadOnlyData
+ | StandardSection::ReadOnlyDataWithRel
+ | StandardSection::ReadOnlyString => (&[], &b".rdata"[..], SectionKind::ReadOnlyData),
+ StandardSection::UninitializedData => {
+ (&[], &b".bss"[..], SectionKind::UninitializedData)
+ }
+ // TLS sections are data sections with a special name.
+ StandardSection::Tls => (&[], &b".tls$"[..], SectionKind::Data),
+ StandardSection::UninitializedTls => {
+ // Unsupported section.
+ (&[], &[], SectionKind::UninitializedTls)
+ }
+ StandardSection::TlsVariables => {
+ // Unsupported section.
+ (&[], &[], SectionKind::TlsVariables)
+ }
+ StandardSection::Common => {
+ // Unsupported section.
+ (&[], &[], SectionKind::Common)
+ }
+ }
+ }
+
+ pub(crate) fn coff_subsection_name(&self, section: &[u8], value: &[u8]) -> Vec<u8> {
+ let mut name = section.to_vec();
+ name.push(b'$');
+ name.extend_from_slice(value);
+ name
+ }
+
+ pub(crate) fn coff_fixup_relocation(&mut self, mut relocation: &mut Relocation) -> i64 {
+ if relocation.kind == RelocationKind::GotRelative {
+ // Use a stub symbol for the relocation instead.
+ // This isn't really a GOT, but it's a similar purpose.
+ // TODO: need to handle DLL imports differently?
+ relocation.kind = RelocationKind::Relative;
+ relocation.symbol = self.coff_add_stub_symbol(relocation.symbol);
+ } else if relocation.kind == RelocationKind::PltRelative {
+ // Windows doesn't need a separate relocation type for
+ // references to functions in import libraries.
+ // For convenience, treat this the same as Relative.
+ relocation.kind = RelocationKind::Relative;
+ }
+
+ let constant = match self.architecture {
+ Architecture::I386 | Architecture::Arm | Architecture::Aarch64 => match relocation.kind
+ {
+ RelocationKind::Relative => {
+ // IMAGE_REL_I386_REL32, IMAGE_REL_ARM_REL32, IMAGE_REL_ARM64_REL32
+ relocation.addend + 4
+ }
+ _ => relocation.addend,
+ },
+ Architecture::X86_64 => match relocation.kind {
+ RelocationKind::Relative => {
+ // IMAGE_REL_AMD64_REL32 through to IMAGE_REL_AMD64_REL32_5
+ if relocation.addend <= -4 && relocation.addend >= -9 {
+ 0
+ } else {
+ relocation.addend + 4
+ }
+ }
+ _ => relocation.addend,
+ },
+ _ => unimplemented!(),
+ };
+ relocation.addend -= constant;
+ constant
+ }
+
+ fn coff_add_stub_symbol(&mut self, symbol_id: SymbolId) -> SymbolId {
+ if let Some(stub_id) = self.stub_symbols.get(&symbol_id) {
+ return *stub_id;
+ }
+ let stub_size = self.architecture.address_size().unwrap().bytes();
+
+ let name = b".rdata$.refptr".to_vec();
+ let section_id = self.add_section(Vec::new(), name, SectionKind::ReadOnlyData);
+ let section = self.section_mut(section_id);
+ section.set_data(vec![0; stub_size as usize], u64::from(stub_size));
+ section.relocations = vec![Relocation {
+ offset: 0,
+ size: stub_size * 8,
+ kind: RelocationKind::Absolute,
+ encoding: RelocationEncoding::Generic,
+ symbol: symbol_id,
+ addend: 0,
+ }];
+
+ let mut name = b".refptr.".to_vec();
+ name.extend_from_slice(&self.symbol(symbol_id).name);
+ let stub_id = self.add_raw_symbol(Symbol {
+ name,
+ value: 0,
+ size: u64::from(stub_size),
+ kind: SymbolKind::Data,
+ scope: SymbolScope::Compilation,
+ weak: false,
+ section: SymbolSection::Section(section_id),
+ flags: SymbolFlags::None,
+ });
+ self.stub_symbols.insert(symbol_id, stub_id);
+
+ stub_id
+ }
+
+ /// Appends linker directives to the `.drectve` section to tell the linker
+ /// to export all symbols with `SymbolScope::Dynamic`.
+ ///
+ /// This must be called after all symbols have been defined.
+ pub fn add_coff_exports(&mut self, style: CoffExportStyle) {
+ assert_eq!(self.format, BinaryFormat::Coff);
+
+ let mut directives = vec![];
+ for symbol in &self.symbols {
+ if symbol.scope == SymbolScope::Dynamic {
+ match style {
+ CoffExportStyle::Msvc => directives.extend(b" /EXPORT:\""),
+ CoffExportStyle::Gnu => directives.extend(b" -export:\""),
+ }
+ directives.extend(&symbol.name);
+ directives.extend(b"\"");
+ if symbol.kind != SymbolKind::Text {
+ match style {
+ CoffExportStyle::Msvc => directives.extend(b",DATA"),
+ CoffExportStyle::Gnu => directives.extend(b",data"),
+ }
+ }
+ }
+ }
+ let drectve = self.add_section(vec![], b".drectve".to_vec(), SectionKind::Linker);
+ self.append_section_data(drectve, &directives, 1);
+ }
+
+ pub(crate) fn coff_write(&self, buffer: &mut dyn WritableBuffer) -> Result<()> {
+ // Calculate offsets of everything, and build strtab.
+ let mut offset = 0;
+ let mut strtab = StringTable::default();
+
+ // COFF header.
+ offset += mem::size_of::<coff::ImageFileHeader>();
+
+ // Section headers.
+ offset += self.sections.len() * mem::size_of::<coff::ImageSectionHeader>();
+
+ // Calculate size of section data and add section strings to strtab.
+ let mut section_offsets = vec![SectionOffsets::default(); self.sections.len()];
+ for (index, section) in self.sections.iter().enumerate() {
+ if section.name.len() > 8 {
+ section_offsets[index].str_id = Some(strtab.add(&section.name));
+ }
+
+ let len = section.data.len();
+ if len != 0 {
+ // TODO: not sure what alignment is required here, but this seems to match LLVM
+ offset = align(offset, 4);
+ section_offsets[index].offset = offset;
+ offset += len;
+ } else {
+ section_offsets[index].offset = 0;
+ }
+
+ // Calculate size of relocations.
+ let mut count = section.relocations.len();
+ if count != 0 {
+ section_offsets[index].reloc_offset = offset;
+ if count > 0xffff {
+ count += 1;
+ }
+ offset += count * mem::size_of::<coff::ImageRelocation>();
+ }
+ }
+
+ // Set COMDAT flags.
+ for comdat in &self.comdats {
+ let symbol = &self.symbols[comdat.symbol.0];
+ let comdat_section = match symbol.section {
+ SymbolSection::Section(id) => id.0,
+ _ => {
+ return Err(Error(format!(
+ "unsupported COMDAT symbol `{}` section {:?}",
+ symbol.name().unwrap_or(""),
+ symbol.section
+ )));
+ }
+ };
+ section_offsets[comdat_section].selection = match comdat.kind {
+ ComdatKind::NoDuplicates => coff::IMAGE_COMDAT_SELECT_NODUPLICATES,
+ ComdatKind::Any => coff::IMAGE_COMDAT_SELECT_ANY,
+ ComdatKind::SameSize => coff::IMAGE_COMDAT_SELECT_SAME_SIZE,
+ ComdatKind::ExactMatch => coff::IMAGE_COMDAT_SELECT_EXACT_MATCH,
+ ComdatKind::Largest => coff::IMAGE_COMDAT_SELECT_LARGEST,
+ ComdatKind::Newest => coff::IMAGE_COMDAT_SELECT_NEWEST,
+ ComdatKind::Unknown => {
+ return Err(Error(format!(
+ "unsupported COMDAT symbol `{}` kind {:?}",
+ symbol.name().unwrap_or(""),
+ comdat.kind
+ )));
+ }
+ };
+ for id in &comdat.sections {
+ let section = &self.sections[id.0];
+ if section.symbol.is_none() {
+ return Err(Error(format!(
+ "missing symbol for COMDAT section `{}`",
+ section.name().unwrap_or(""),
+ )));
+ }
+ if id.0 != comdat_section {
+ section_offsets[id.0].selection = coff::IMAGE_COMDAT_SELECT_ASSOCIATIVE;
+ section_offsets[id.0].associative_section = comdat_section as u16 + 1;
+ }
+ }
+ }
+
+ // Calculate size of symbols and add symbol strings to strtab.
+ let mut symbol_offsets = vec![SymbolOffsets::default(); self.symbols.len()];
+ let mut symtab_count = 0;
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ symbol_offsets[index].index = symtab_count;
+ symtab_count += 1;
+ match symbol.kind {
+ SymbolKind::File => {
+ // Name goes in auxilary symbol records.
+ let aux_count = (symbol.name.len() + coff::IMAGE_SIZEOF_SYMBOL - 1)
+ / coff::IMAGE_SIZEOF_SYMBOL;
+ symbol_offsets[index].aux_count = aux_count as u8;
+ symtab_count += aux_count;
+ // Don't add name to strtab.
+ continue;
+ }
+ SymbolKind::Section => {
+ symbol_offsets[index].aux_count = 1;
+ symtab_count += 1;
+ }
+ _ => {}
+ }
+ if symbol.name.len() > 8 {
+ symbol_offsets[index].str_id = Some(strtab.add(&symbol.name));
+ }
+ }
+
+ // Calculate size of symtab.
+ let symtab_offset = offset;
+ let symtab_len = symtab_count * coff::IMAGE_SIZEOF_SYMBOL;
+ offset += symtab_len;
+
+ // Calculate size of strtab.
+ let strtab_offset = offset;
+ let mut strtab_data = Vec::new();
+ // First 4 bytes of strtab are the length.
+ strtab.write(4, &mut strtab_data);
+ let strtab_len = strtab_data.len() + 4;
+ offset += strtab_len;
+
+ // Start writing.
+ buffer
+ .reserve(offset)
+ .map_err(|_| Error(String::from("Cannot allocate buffer")))?;
+
+ // Write file header.
+ let header = coff::ImageFileHeader {
+ machine: U16::new(
+ LE,
+ match self.architecture {
+ Architecture::Arm => coff::IMAGE_FILE_MACHINE_ARMNT,
+ Architecture::Aarch64 => coff::IMAGE_FILE_MACHINE_ARM64,
+ Architecture::I386 => coff::IMAGE_FILE_MACHINE_I386,
+ Architecture::X86_64 => coff::IMAGE_FILE_MACHINE_AMD64,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented architecture {:?}",
+ self.architecture
+ )));
+ }
+ },
+ ),
+ number_of_sections: U16::new(LE, self.sections.len() as u16),
+ time_date_stamp: U32::default(),
+ pointer_to_symbol_table: U32::new(LE, symtab_offset as u32),
+ number_of_symbols: U32::new(LE, symtab_count as u32),
+ size_of_optional_header: U16::default(),
+ characteristics: match self.flags {
+ FileFlags::Coff { characteristics } => U16::new(LE, characteristics),
+ _ => U16::default(),
+ },
+ };
+ buffer.write(&header);
+
+ // Write section headers.
+ for (index, section) in self.sections.iter().enumerate() {
+ let mut characteristics = if let SectionFlags::Coff {
+ characteristics, ..
+ } = section.flags
+ {
+ characteristics
+ } else {
+ match section.kind {
+ SectionKind::Text => {
+ coff::IMAGE_SCN_CNT_CODE
+ | coff::IMAGE_SCN_MEM_EXECUTE
+ | coff::IMAGE_SCN_MEM_READ
+ }
+ SectionKind::Data => {
+ coff::IMAGE_SCN_CNT_INITIALIZED_DATA
+ | coff::IMAGE_SCN_MEM_READ
+ | coff::IMAGE_SCN_MEM_WRITE
+ }
+ SectionKind::UninitializedData => {
+ coff::IMAGE_SCN_CNT_UNINITIALIZED_DATA
+ | coff::IMAGE_SCN_MEM_READ
+ | coff::IMAGE_SCN_MEM_WRITE
+ }
+ SectionKind::ReadOnlyData
+ | SectionKind::ReadOnlyDataWithRel
+ | SectionKind::ReadOnlyString => {
+ coff::IMAGE_SCN_CNT_INITIALIZED_DATA | coff::IMAGE_SCN_MEM_READ
+ }
+ SectionKind::Debug | SectionKind::Other | SectionKind::OtherString => {
+ coff::IMAGE_SCN_CNT_INITIALIZED_DATA
+ | coff::IMAGE_SCN_MEM_READ
+ | coff::IMAGE_SCN_MEM_DISCARDABLE
+ }
+ SectionKind::Linker => coff::IMAGE_SCN_LNK_INFO | coff::IMAGE_SCN_LNK_REMOVE,
+ SectionKind::Common
+ | SectionKind::Tls
+ | SectionKind::UninitializedTls
+ | SectionKind::TlsVariables
+ | SectionKind::Note
+ | SectionKind::Unknown
+ | SectionKind::Metadata
+ | SectionKind::Elf(_) => {
+ return Err(Error(format!(
+ "unimplemented section `{}` kind {:?}",
+ section.name().unwrap_or(""),
+ section.kind
+ )));
+ }
+ }
+ };
+ if section_offsets[index].selection != 0 {
+ characteristics |= coff::IMAGE_SCN_LNK_COMDAT;
+ };
+ if section.relocations.len() > 0xffff {
+ characteristics |= coff::IMAGE_SCN_LNK_NRELOC_OVFL;
+ }
+ characteristics |= match section.align {
+ 1 => coff::IMAGE_SCN_ALIGN_1BYTES,
+ 2 => coff::IMAGE_SCN_ALIGN_2BYTES,
+ 4 => coff::IMAGE_SCN_ALIGN_4BYTES,
+ 8 => coff::IMAGE_SCN_ALIGN_8BYTES,
+ 16 => coff::IMAGE_SCN_ALIGN_16BYTES,
+ 32 => coff::IMAGE_SCN_ALIGN_32BYTES,
+ 64 => coff::IMAGE_SCN_ALIGN_64BYTES,
+ 128 => coff::IMAGE_SCN_ALIGN_128BYTES,
+ 256 => coff::IMAGE_SCN_ALIGN_256BYTES,
+ 512 => coff::IMAGE_SCN_ALIGN_512BYTES,
+ 1024 => coff::IMAGE_SCN_ALIGN_1024BYTES,
+ 2048 => coff::IMAGE_SCN_ALIGN_2048BYTES,
+ 4096 => coff::IMAGE_SCN_ALIGN_4096BYTES,
+ 8192 => coff::IMAGE_SCN_ALIGN_8192BYTES,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented section `{}` align {}",
+ section.name().unwrap_or(""),
+ section.align
+ )));
+ }
+ };
+ let mut coff_section = coff::ImageSectionHeader {
+ name: [0; 8],
+ virtual_size: U32::default(),
+ virtual_address: U32::default(),
+ size_of_raw_data: U32::new(LE, section.size as u32),
+ pointer_to_raw_data: U32::new(LE, section_offsets[index].offset as u32),
+ pointer_to_relocations: U32::new(LE, section_offsets[index].reloc_offset as u32),
+ pointer_to_linenumbers: U32::default(),
+ number_of_relocations: if section.relocations.len() > 0xffff {
+ U16::new(LE, 0xffff)
+ } else {
+ U16::new(LE, section.relocations.len() as u16)
+ },
+ number_of_linenumbers: U16::default(),
+ characteristics: U32::new(LE, characteristics),
+ };
+ if section.name.len() <= 8 {
+ coff_section.name[..section.name.len()].copy_from_slice(&section.name);
+ } else {
+ let mut str_offset = strtab.get_offset(section_offsets[index].str_id.unwrap());
+ if str_offset <= 9_999_999 {
+ let mut name = [0; 7];
+ let mut len = 0;
+ if str_offset == 0 {
+ name[6] = b'0';
+ len = 1;
+ } else {
+ while str_offset != 0 {
+ let rem = (str_offset % 10) as u8;
+ str_offset /= 10;
+ name[6 - len] = b'0' + rem;
+ len += 1;
+ }
+ }
+ coff_section.name = [0; 8];
+ coff_section.name[0] = b'/';
+ coff_section.name[1..][..len].copy_from_slice(&name[7 - len..]);
+ } else if str_offset as u64 <= 0xf_ffff_ffff {
+ coff_section.name[0] = b'/';
+ coff_section.name[1] = b'/';
+ for i in 0..6 {
+ let rem = (str_offset % 64) as u8;
+ str_offset /= 64;
+ let c = match rem {
+ 0..=25 => b'A' + rem,
+ 26..=51 => b'a' + rem - 26,
+ 52..=61 => b'0' + rem - 52,
+ 62 => b'+',
+ 63 => b'/',
+ _ => unreachable!(),
+ };
+ coff_section.name[7 - i] = c;
+ }
+ } else {
+ return Err(Error(format!("invalid section name offset {}", str_offset)));
+ }
+ }
+ buffer.write(&coff_section);
+ }
+
+ // Write section data and relocations.
+ for (index, section) in self.sections.iter().enumerate() {
+ let len = section.data.len();
+ if len != 0 {
+ write_align(buffer, 4);
+ debug_assert_eq!(section_offsets[index].offset, buffer.len());
+ buffer.write_bytes(&section.data);
+ }
+
+ if !section.relocations.is_empty() {
+ debug_assert_eq!(section_offsets[index].reloc_offset, buffer.len());
+ if section.relocations.len() > 0xffff {
+ let coff_relocation = coff::ImageRelocation {
+ virtual_address: U32Bytes::new(LE, section.relocations.len() as u32 + 1),
+ symbol_table_index: U32Bytes::new(LE, 0),
+ typ: U16Bytes::new(LE, 0),
+ };
+ buffer.write(&coff_relocation);
+ }
+ for reloc in &section.relocations {
+ //assert!(reloc.implicit_addend);
+ let typ = match self.architecture {
+ Architecture::I386 => match (reloc.kind, reloc.size, reloc.addend) {
+ (RelocationKind::Absolute, 16, 0) => coff::IMAGE_REL_I386_DIR16,
+ (RelocationKind::Relative, 16, 0) => coff::IMAGE_REL_I386_REL16,
+ (RelocationKind::Absolute, 32, 0) => coff::IMAGE_REL_I386_DIR32,
+ (RelocationKind::ImageOffset, 32, 0) => coff::IMAGE_REL_I386_DIR32NB,
+ (RelocationKind::SectionIndex, 16, 0) => coff::IMAGE_REL_I386_SECTION,
+ (RelocationKind::SectionOffset, 32, 0) => coff::IMAGE_REL_I386_SECREL,
+ (RelocationKind::SectionOffset, 7, 0) => coff::IMAGE_REL_I386_SECREL7,
+ (RelocationKind::Relative, 32, -4) => coff::IMAGE_REL_I386_REL32,
+ (RelocationKind::Coff(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::X86_64 => match (reloc.kind, reloc.size, reloc.addend) {
+ (RelocationKind::Absolute, 64, 0) => coff::IMAGE_REL_AMD64_ADDR64,
+ (RelocationKind::Absolute, 32, 0) => coff::IMAGE_REL_AMD64_ADDR32,
+ (RelocationKind::ImageOffset, 32, 0) => coff::IMAGE_REL_AMD64_ADDR32NB,
+ (RelocationKind::Relative, 32, -4) => coff::IMAGE_REL_AMD64_REL32,
+ (RelocationKind::Relative, 32, -5) => coff::IMAGE_REL_AMD64_REL32_1,
+ (RelocationKind::Relative, 32, -6) => coff::IMAGE_REL_AMD64_REL32_2,
+ (RelocationKind::Relative, 32, -7) => coff::IMAGE_REL_AMD64_REL32_3,
+ (RelocationKind::Relative, 32, -8) => coff::IMAGE_REL_AMD64_REL32_4,
+ (RelocationKind::Relative, 32, -9) => coff::IMAGE_REL_AMD64_REL32_5,
+ (RelocationKind::SectionIndex, 16, 0) => coff::IMAGE_REL_AMD64_SECTION,
+ (RelocationKind::SectionOffset, 32, 0) => coff::IMAGE_REL_AMD64_SECREL,
+ (RelocationKind::SectionOffset, 7, 0) => coff::IMAGE_REL_AMD64_SECREL7,
+ (RelocationKind::Coff(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Arm => match (reloc.kind, reloc.size, reloc.addend) {
+ (RelocationKind::Absolute, 32, 0) => coff::IMAGE_REL_ARM_ADDR32,
+ (RelocationKind::ImageOffset, 32, 0) => coff::IMAGE_REL_ARM_ADDR32NB,
+ (RelocationKind::Relative, 32, -4) => coff::IMAGE_REL_ARM_REL32,
+ (RelocationKind::SectionIndex, 16, 0) => coff::IMAGE_REL_ARM_SECTION,
+ (RelocationKind::SectionOffset, 32, 0) => coff::IMAGE_REL_ARM_SECREL,
+ (RelocationKind::Coff(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Aarch64 => match (reloc.kind, reloc.size, reloc.addend) {
+ (RelocationKind::Absolute, 32, 0) => coff::IMAGE_REL_ARM64_ADDR32,
+ (RelocationKind::ImageOffset, 32, 0) => coff::IMAGE_REL_ARM64_ADDR32NB,
+ (RelocationKind::SectionIndex, 16, 0) => coff::IMAGE_REL_ARM64_SECTION,
+ (RelocationKind::SectionOffset, 32, 0) => coff::IMAGE_REL_ARM64_SECREL,
+ (RelocationKind::Absolute, 64, 0) => coff::IMAGE_REL_ARM64_ADDR64,
+ (RelocationKind::Relative, 32, -4) => coff::IMAGE_REL_ARM64_REL32,
+ (RelocationKind::Coff(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ _ => {
+ return Err(Error(format!(
+ "unimplemented architecture {:?}",
+ self.architecture
+ )));
+ }
+ };
+ let coff_relocation = coff::ImageRelocation {
+ virtual_address: U32Bytes::new(LE, reloc.offset as u32),
+ symbol_table_index: U32Bytes::new(
+ LE,
+ symbol_offsets[reloc.symbol.0].index as u32,
+ ),
+ typ: U16Bytes::new(LE, typ),
+ };
+ buffer.write(&coff_relocation);
+ }
+ }
+ }
+
+ // Write symbols.
+ debug_assert_eq!(symtab_offset, buffer.len());
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ let mut name = &symbol.name[..];
+ let section_number = match symbol.section {
+ SymbolSection::None => {
+ debug_assert_eq!(symbol.kind, SymbolKind::File);
+ coff::IMAGE_SYM_DEBUG
+ }
+ SymbolSection::Undefined => coff::IMAGE_SYM_UNDEFINED,
+ SymbolSection::Absolute => coff::IMAGE_SYM_ABSOLUTE,
+ SymbolSection::Common => coff::IMAGE_SYM_UNDEFINED,
+ SymbolSection::Section(id) => id.0 as u16 + 1,
+ };
+ let typ = if symbol.kind == SymbolKind::Text {
+ coff::IMAGE_SYM_DTYPE_FUNCTION << coff::IMAGE_SYM_DTYPE_SHIFT
+ } else {
+ coff::IMAGE_SYM_TYPE_NULL
+ };
+ let storage_class = match symbol.kind {
+ SymbolKind::File => {
+ // Name goes in auxilary symbol records.
+ name = b".file";
+ coff::IMAGE_SYM_CLASS_FILE
+ }
+ SymbolKind::Section => coff::IMAGE_SYM_CLASS_STATIC,
+ SymbolKind::Label => coff::IMAGE_SYM_CLASS_LABEL,
+ SymbolKind::Text | SymbolKind::Data | SymbolKind::Tls => {
+ match symbol.section {
+ SymbolSection::None => {
+ return Err(Error(format!(
+ "missing section for symbol `{}`",
+ symbol.name().unwrap_or("")
+ )));
+ }
+ SymbolSection::Undefined | SymbolSection::Common => {
+ coff::IMAGE_SYM_CLASS_EXTERNAL
+ }
+ SymbolSection::Absolute | SymbolSection::Section(_) => {
+ match symbol.scope {
+ // TODO: does this need aux symbol records too?
+ _ if symbol.weak => coff::IMAGE_SYM_CLASS_WEAK_EXTERNAL,
+ SymbolScope::Unknown => {
+ return Err(Error(format!(
+ "unimplemented symbol `{}` scope {:?}",
+ symbol.name().unwrap_or(""),
+ symbol.scope
+ )));
+ }
+ SymbolScope::Compilation => coff::IMAGE_SYM_CLASS_STATIC,
+ SymbolScope::Linkage | SymbolScope::Dynamic => {
+ coff::IMAGE_SYM_CLASS_EXTERNAL
+ }
+ }
+ }
+ }
+ }
+ SymbolKind::Unknown | SymbolKind::Null => {
+ return Err(Error(format!(
+ "unimplemented symbol `{}` kind {:?}",
+ symbol.name().unwrap_or(""),
+ symbol.kind
+ )));
+ }
+ };
+ let number_of_aux_symbols = symbol_offsets[index].aux_count;
+ let value = if symbol.section == SymbolSection::Common {
+ symbol.size as u32
+ } else {
+ symbol.value as u32
+ };
+ let mut coff_symbol = coff::ImageSymbol {
+ name: [0; 8],
+ value: U32Bytes::new(LE, value),
+ section_number: U16Bytes::new(LE, section_number as u16),
+ typ: U16Bytes::new(LE, typ),
+ storage_class,
+ number_of_aux_symbols,
+ };
+ if name.len() <= 8 {
+ coff_symbol.name[..name.len()].copy_from_slice(name);
+ } else {
+ let str_offset = strtab.get_offset(symbol_offsets[index].str_id.unwrap());
+ coff_symbol.name[4..8].copy_from_slice(&u32::to_le_bytes(str_offset as u32));
+ }
+ buffer.write(&coff_symbol);
+
+ // Write auxiliary symbols.
+ match symbol.kind {
+ SymbolKind::File => {
+ let aux_len = number_of_aux_symbols as usize * coff::IMAGE_SIZEOF_SYMBOL;
+ debug_assert!(aux_len >= symbol.name.len());
+ let old_len = buffer.len();
+ buffer.write_bytes(&symbol.name);
+ buffer.resize(old_len + aux_len);
+ }
+ SymbolKind::Section => {
+ debug_assert_eq!(number_of_aux_symbols, 1);
+ let section_index = symbol.section.id().unwrap().0;
+ let section = &self.sections[section_index];
+ let aux = coff::ImageAuxSymbolSection {
+ length: U32Bytes::new(LE, section.size as u32),
+ number_of_relocations: if section.relocations.len() > 0xffff {
+ U16Bytes::new(LE, 0xffff)
+ } else {
+ U16Bytes::new(LE, section.relocations.len() as u16)
+ },
+ number_of_linenumbers: U16Bytes::default(),
+ check_sum: U32Bytes::new(LE, checksum(section.data())),
+ number: U16Bytes::new(
+ LE,
+ section_offsets[section_index].associative_section,
+ ),
+ selection: section_offsets[section_index].selection,
+ reserved: 0,
+ // TODO: bigobj
+ high_number: U16Bytes::default(),
+ };
+ buffer.write(&aux);
+ }
+ _ => {
+ debug_assert_eq!(number_of_aux_symbols, 0);
+ }
+ }
+ }
+
+ // Write strtab section.
+ debug_assert_eq!(strtab_offset, buffer.len());
+ buffer.write_bytes(&u32::to_le_bytes(strtab_len as u32));
+ buffer.write_bytes(&strtab_data);
+
+ debug_assert_eq!(offset, buffer.len());
+
+ Ok(())
+ }
+}
+
+// JamCRC
+fn checksum(data: &[u8]) -> u32 {
+ let mut hasher = crc32fast::Hasher::new_with_initial(0xffff_ffff);
+ hasher.update(data);
+ !hasher.finalize()
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 04:56:43 +0000