XmlRpcValue::_doubleFormat should be used during write. (#2003)

* XmlRpcValue::_doubleFormat should be used during write.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* allocate buffer dynamically for XmlRpcValue::_doubleFormat if necessary.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* add test for XmlRpcValue::_doubleFormat.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* check return code from std::snprintf, save/restore DoubleFormat for test.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* add one time warning message for DoubleFormat.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* use XmlRpcUtil::error instead of ROS_ERROR.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* use static_cast and minor fixes.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* delete unrelated change and fix invalid format case.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

* get rid of redundant condition from if statement.

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

utilities/xmlrpcpp/src/XmlRpcValue.cpp

@@ -14,6 +14,7 @@
 #endif
 
 #include <sstream>
+#include <mutex>
 
 namespace XmlRpc {
 
@@ -610,7 +611,28 @@ namespace XmlRpc {
       default:           break;
       case TypeBoolean:  os << _value.asBool; break;
       case TypeInt:      os << _value.asInt; break;
-      case TypeDouble:   os << _value.asDouble; break;
+      case TypeDouble:
+        {
+          static std::once_flag once;
+          char buf[128]; // Should be long enough
+          int required_size = std::snprintf(buf, sizeof(buf)-1,
+                                getDoubleFormat().c_str(), _value.asDouble);
+          if (required_size < 0) {
+            std::call_once(once,
+              [](){XmlRpcUtil::error("Failed to format with %s", getDoubleFormat().c_str());});
+            os << _value.asDouble;
+          } else if (required_size < static_cast<int>(sizeof(buf))) {
+            buf[sizeof(buf)-1] = 0;
+            os << buf;
+          } else { // required_size >= static_cast<int>(sizeof(buf)
+            char required_buf[required_size+1];
+            std::snprintf(required_buf, required_size,
+              getDoubleFormat().c_str(), _value.asDouble);
+            required_buf[required_size] = 0;
+            os << required_buf;
+          }
+          break;
+        }
       case TypeString:   os << *_value.asString; break;
       case TypeDateTime:
         {

utilities/xmlrpcpp/test/TestValues.cpp

@@ -126,6 +126,40 @@ TEST(XmlRpc, testDouble) {
   std::stringstream ss;
   ss << d;
   EXPECT_EQ("43.7", ss.str());
+  ss.str("");
+
+  // Test format
+  const XmlRpc::XmlRpcValue a(2.0);
+  ASSERT_EQ(XmlRpcValue::TypeDouble, d.getType());
+  const std::string save_format = XmlRpc::XmlRpcValue::getDoubleFormat();
+
+  XmlRpc::XmlRpcValue::setDoubleFormat("%32.10f");
+  ss << a;
+  EXPECT_EQ("                    2.0000000000", ss.str());
+  ss.str("");
+
+  XmlRpc::XmlRpcValue::setDoubleFormat("%10.32f");
+  ss << a;
+  EXPECT_EQ("2.00000000000000000000000000000000", ss.str());
+  ss.str("");
+
+  XmlRpc::XmlRpcValue::setDoubleFormat("%128.10f");
+  ss << a;
+  EXPECT_EQ("                                "
+            "                                "
+            "                                "
+            "                    2.000000000", ss.str());
+  ss.str("");
+
+  XmlRpc::XmlRpcValue::setDoubleFormat("%10.128f");
+  ss << a;
+  EXPECT_EQ("2.000000000000000000000000000000"
+            "00000000000000000000000000000000"
+            "00000000000000000000000000000000"
+            "000000000000000000000000000000000", ss.str());
+  ss.str("");
+
+  XmlRpc::XmlRpcValue::setDoubleFormat(save_format.c_str());
 }
 
 TEST(XmlRpc, testString) {