PR sanitizer/77631

PR sanitizer/77631

    * Makefile.am: Updated.
    * configure.ac: Updated.
    * configure: Regenerated.
    * Makefile.in: Regenerated.
    * elf.c (enum type_of_file): New enum.
    (enum type_of_elf): New enum.
    (enum debug_path): New enum.
    (get_uint32): New function.
    (get_crc32): New function.
    (base_name_len): New function.
    (check_sum): New function. Verify sum.
    (process_elf_header): New function. Process elf header.
    (elf_get_section_by_name): New function. Get section by name.
    (backtrace_readlink): New function. Get type of file from filename.
    (resolve_realname): New function. Resolve real name if file is link.
    (backtrace_resolve_realname): New function. Resolve real name for any
    file type.
    (search_for_debugfile): New function. Search for debug file in known
    paths.
    (open_debugfile_by_gnulink): New function. Open debug file with
    gnulink.
    (hex): New function. Convert to hex.
    (get_build_id_name): New function. Generate build-id name.
    (open_debugfile_by_build_id): New function. Open debug file with
    build-id.
    (backtrace_open_debugfile): New function. Open debug file.
    (get_exec_filename): New function. Get pathname of the executable.
    (elf_add): Move code which reads elf header, headers section and names
    section to process_elf_header.
    Call backtrace_open_debugfile_file for executable.
    (phdr_callback): Call backtrace_open_debugfile function for shared
    library.
    * crc32.c: New file.
    (gnu_debuglink_crc32): New function. Generate crc32 sum.

Change-Id: I30d9fbcfa24b3aadf3b7c54525dccedd60cd1a5d