cromo: Add ExtractUint32 function

cromo: Add ExtractUint32 function

BUG=chromium-os:11879
TEST=use 'modem status' to monitor activation state while activating.
Notice that cromo now reports state 1 --
MM_ACTIVATION_STATE_ACTIVATING

Committed: http://chrome-svn/viewvc/chromeos?view=rev&revision=62bbe91

[rochberg, 2011-03-01 18:25:53]

On 2011/03/01 18:04:01, Jason Glasgow wrote:

I'd love to see a return type of uint32.  
LGTM otherwise

[ers, 2011-03-01 20:32:59]

FYI, you can do something like this using templates

template<typename T>
T get_value(DBusPropertyMap::const_iterator p) {
  T retval;
  return retval;
}

template<> inline const char *get_value<const
char*>(DBusPropertyMap::const_iterator p) {
  return p->second.reader().get_string();
}

template<> inline uint32 get_value<uint32_t>(DBusPropertyMap::const_iterator
p) {
  return p->second.reader().get_uint32();
}

template<typename T>
T ExtractValue(const DBusPropertyMap properties,
               const char *key,
               T not_found_response,
               DBus::Error &error) {
  DBusPropertyMap::const_iterator p;
  T to_return = not_found_response;
  try {
    p = properties.find(key);
    if (p != properties.end()) {
      to_return = get_value<T>(p);
    }
  } catch (const DBus::Error &e) {
//    LOG(ERROR)<<"Bad type for: " << key;
    // Setting an already-set error causes an assert fail inside dbus-c++.
    if (!error.is_set()) {
    // NB: the copy constructor for DBus::Error causes a template to
    // be instantiated that kills our -Werror build
      error.set(e.name(), e.message());
    }
  }
  return to_return;
}


On Tue, Mar 1, 2011 at 1:25 PM, <rochberg@chromium.org> wrote:

> On 2011/03/01 18:04:01, Jason Glasgow wrote:
>
> I'd love to see a return type of uint32.
> LGTM otherwise
>
>
> http://codereview.chromium.org/6592070/
>