Method resolve_exec_path

backward.hpp:1256–1277

  TraceResolverLinuxBase()
      : argv0_(get_argv0()), exec_path_(read_symlink("/proc/self/exe")) {}
  std::string resolve_exec_path(Dl_info &symbol_info) const {
    // mutates symbol_info.dli_fname to be filename to open and returns filename
    // to display
    if (symbol_info.dli_fname == argv0_) {
      // dladdr returns argv[0] in dli_fname for symbols contained in
      // the main executable, which is not a valid path if the
      // executable was found by a search of the PATH environment
      // variable; In that case, we actually open /proc/self/exe, which
      // is always the actual executable (even if it was deleted/replaced!)
      // but display the path that /proc/self/exe links to.
      // However, this right away reduces probability of successful symbol
      // resolution, because libbfd may try to find *.debug files in the
      // same dir, in case symbols are stripped. As a result, it may try
      // to find a file /proc/self/<exe_name>.debug, which obviously does
      // not exist. /proc/self/exe is a last resort. First load attempt
      // should go for the original executable file path.
      symbol_info.dli_fname = "/proc/self/exe";
      return exec_path_;
    } else {
      return symbol_info.dli_fname;
    }
  }

private:
  std::string argv0_;