Function PrintCode

core/debug.cc:238–286

addr2line must be available. Returns the code lines [lineno - context, lineno + context] */

// addr2line must be available.
// Returns the code lines [lineno - context, lineno + context] */
static std::string PrintCode(std::string symbol, int context) {
  std::ostringstream ret;
  char objfile[PATH_MAX];
  char addr[1024];

  // Symbol examples:
  // ./bessd(run_worker+0x8e) [0x419d0e]
  // ./bessd() [0x4149d8]
  // /home/foo/.../source.so(_ZN6Source7RunTaskEPv+0x55) [0x7f09e912c7b5]
  Parse(symbol, "%[^(](%*s [%[^]]]", objfile, addr);

  uintptr_t sym_addr = std::strtoull(addr, nullptr, 16);
  uintptr_t obj_addr = GetRelativeAddress(sym_addr);

  std::string cmd =
      Format("addr2line -C -i -f -p -e %s 0x%" PRIxPTR " 2> /dev/null", objfile,
             obj_addr);

  std::istringstream result(RunCommand(cmd));
  std::string line;

  while (std::getline(result, line)) {
    // addr2line examples:
    // sched_free at /home/sangjin/.../tc.c:277 (discriminator 2)
    // run_worker at /home/sangjin/bess/core/module.c:653

    ret << "    " << line << std::endl;

    auto pos = line.find(" at ");
    if (pos == std::string::npos) {
      // failed to parse the line
      continue;
    }

    // Remove unnecessary characters (up to " at ", including itself)
    line.erase(0, pos + 4);

    char filename[PATH_MAX];
    int lineno;

    if (Parse(line, "%[^:]:%d", filename, &lineno) == 2) {
      if (std::string(filename) != "??" && lineno != 0) {
        ret << FetchLine(filename, lineno, context);
      }
    }
  }

  return ret.str();
}

static void *trap_ip;
static std::string oops_msg;