cromo: Add ExtractUint32 function

utilities.cc

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Plugin tests link against this file, but not against the rest of
 // cromo.  Therefore this file should not have dependencies on the
 // rest of cromo.
 #include "utilities.h"
 
 #include <glog/logging.h>
@@ skipping 18 matching lines @@
     // 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;
 }
 
+uint32_t ExtractUint32(const DBusPropertyMap properties,
+                       const char *key,
+                       uint32_t not_found_response,
+                       DBus::Error &error) {
+  DBusPropertyMap::const_iterator p;
+  unsigned int to_return = not_found_response;
+  try {
+    p = properties.find(key);
+    if (p != properties.end()) {
+      to_return = p->second.reader().get_uint32();
+    }
+  } 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;
+}
+
 bool HexEsnToDecimal(const std::string &esn_hex, std::string *out) {
   size_t length = esn_hex.length();
   if (length > 8) {
     LOG(ERROR) << "Long ESN: " << esn_hex;
     return false;
   }
   errno = 0;
   const char *start = esn_hex.c_str();
   char *end;
   uint32_t esn = strtoul(start, &end, 16);
@@ skipping 11 matching lines @@
   if (rc != 11) {
     LOG(ERROR) << "Format failure";
     return false;
   }
   if (out) {
     *out = decimal;
   }
   return true;
 }
 }  // namespace utilities