#moonbit-community/elf

#Capabilities

• Parses both ELFCLASS32 and ELFCLASS64 files.
• Handles little-endian and big-endian ELF data through the parsed Endian value.
• Keeps table parsing lazy: SectionHeaderTable, SegmentTable, SymbolTable, DynamicTable, and version iterators parse entries on demand.
• Provides checked offset arithmetic and returns ParseError for malformed or truncated input instead of reading outside the supplied byte slice.
• Exposes helpers for common sections and segments: string tables, relocations, notes, symbol tables, .dynamic, SysV .hash, GNU .gnu.hash, and GNU symbol versioning.
• Returns raw section and segment byte views. Compressed sections are identified and their CompressionHeader is returned, but decompression is intentionally left to the caller.

#Quick Start

///|
test "readme quick start" {
  let data = @fs.read_file_to_bytes("testdata/basic.x86_64")
  let elf = @elf.ElfBytes::minimal_parse(data[:])

  assert_true(elf.ehdr.class is ELF64)
  assert_true(elf.ehdr.endianness is Little)
  assert_eq(elf.ehdr.e_machine, @elf.EM_X86_64)

  let text = match elf.section_header_by_name(".text") {
    Some(shdr) => shdr
    None => fail("expected .text section")
  }
  let (bytes, compression) = elf.section_data(text)
  assert_true(bytes.length() > 0)
  assert_true(compression is None)
}

#Common Data

///|
test "readme common data" {
  let data = @fs.read_file_to_bytes("testdata/symver.x86_64.so")
  let elf = @elf.ElfBytes::minimal_parse(data[:])
  let common = elf.find_common_data()

  let dynsyms = match common.dynsyms {
    Some(table) => table
    None => fail("expected dynamic symbol table")
  }
  let dynstrs = match common.dynsyms_strs {
    Some(table) => table
    None => fail("expected dynamic symbol strings")
  }
  let hash = match common.sysv_hash {
    Some(table) => table
    None => fail("expected SysV hash table")
  }

  let (index, symbol) = match hash.find(b"memset"[:], dynsyms, dynstrs) {
    Some(pair) => pair
    None => fail("expected memset")
  }
  assert_eq(index, 2)
  assert_eq(dynstrs.get(symbol.st_name.reinterpret_as_int()), "memset")
}

#Parsing Model

1. Errors can occur when a table entry is requested, not only when the file is opened.
2. You can cheaply obtain several views over the same file, such as a dynamic symbol table, its linked string table, and a hash table.

#Error Handling

• BadMagic for bytes that do not start with 0x7f, 'E', 'L', 'F'.
• UnsupportedElfClass and UnsupportedElfEndianness for unknown identity bytes.
• BadOffset for logical table indices or string-table offsets that are out of bounds.
• SliceReadError for truncated files or raw byte ranges that cannot be sliced from the supplied data.
• BadEntsize when a table declares an entry size that does not match the ELF class.
• UnexpectedSectionType and UnexpectedSegmentType when a helper is used on the wrong kind of section or segment.
• StringTableMissingNul and Utf8Error for malformed string table data.

#API Map

#Notes