Method parse

src/linux/fs.cpp:301–373

Try<MountInfoTable::Entry> MountInfoTable::Entry::parse(const string& s)
{
  MountInfoTable::Entry entry;

  const string separator = " - ";
  size_t pos = s.find(separator);
  if (pos == string::npos) {
    return Error("Could not find separator ' - '");
  }

  // First group of fields (before the separator): 6 required fields
  // then zero or more optional fields
  vector<string> tokens = strings::tokenize(s.substr(0, pos), " ");
  if (tokens.size() < 6) {
    return Error("Failed to parse entry");
  }

  Try<int> id = numify<int>(tokens[0]);
  if (id.isError()) {
    return Error("Mount ID is not a number");
  }
  entry.id = id.get();

  Try<int> parent = numify<int>(tokens[1]);
  if (parent.isError()) {
    return Error("Parent ID is not a number");
  }
  entry.parent = parent.get();

  // Parse out the major:minor device number.
  vector<string> device = strings::split(tokens[2], ":");
  if (device.size() != 2) {
    return Error("Invalid major:minor device number");
  }

  Try<int> major = numify<int>(device[0]);
  if (major.isError()) {
    return Error("Device major is not a number");
  }

  Try<int> minor = numify<int>(device[1]);
  if (minor.isError()) {
    return Error("Device minor is not a number");
  }

  entry.devno = makedev(major.get(), minor.get());

  entry.root = tokens[3];
  entry.target = tokens[4];

  entry.vfsOptions = tokens[5];

  // The "proc" manpage states there can be zero or more optional
  // fields. The kernel source (fs/proc_namespace.c) has the optional
  // fields ("tagged fields") separated by " " when printing the table
  // (see show_mountinfo()).
  if (tokens.size() > 6) {
    tokens.erase(tokens.begin(), tokens.begin() + 6);