Integrate changes from internal code.

protoc
* Enum values may now have custom options, using syntax similar to field
  options.
* Fixed bug where .proto files which use custom options but don't actually
  define them (i.e. they import another .proto file defining the options)
  had to explicitly import descriptor.proto.
* Adjacent string literals in .proto files will now be concatenated, like in
  C.

C++
* Generated message classes now have a Swap() method which efficiently swaps
  the contents of two objects.
* All message classes now have a SpaceUsed() method which returns an estimate
  of the number of bytes of allocated memory currently owned by the object.
  This is particularly useful when you are reusing a single message object
  to improve performance but want to make sure it doesn't bloat up too large.
* New method Message::SerializeAsString() returns a string containing the
  serialized data.  May be more convenient than calling
  SerializeToString(string*).
* In debug mode, log error messages when string-type fields are found to
  contain bytes that are not valid UTF-8.
* Fixed bug where a message with multiple extension ranges couldn't parse
  extensions.
* Fixed bug where MergeFrom(const Message&) didn't do anything if invoked on
  a message that contained no fields (but possibly contained extensions).
* Fixed ShortDebugString() to not be O(n^2).  Durr.
* Fixed crash in TextFormat parsing if the first token in the input caused a
  tokenization error.

Java
* New overload of mergeFrom() which parses a slice of a byte array instead
  of the whole thing.
* New method ByteString.asReadOnlyByteBuffer() does what it sounds like.
* Improved performance of isInitialized() when optimizing for code size.

Python
* Corrected ListFields() signature in Message base class to match what
  subclasses actually implement.
* Some minor refactoring.

1 files changed, 22 insertions, 0 deletions

diff --git a/src/google/protobuf/message.cc b/src/google/protobuf/message.cc
index fddbdcb8..f6c932ff 100644
--- a/src/google/protobuf/message.cc
+++ b/src/google/protobuf/message.cc
@@ -204,6 +204,10 @@ void Message::SetCachedSize(int size) const {
                 "Must implement one or the other.";
 }
 
+int Message::SpaceUsed() const {
+  return GetReflection()->SpaceUsed(*this);
+}
+
 bool Message::SerializeToCodedStream(io::CodedOutputStream* output) const {
   GOOGLE_DCHECK(IsInitialized()) << InitializationErrorMessage("serialize", *this);
   return SerializePartialToCodedStream(output);
@@ -291,6 +295,24 @@ bool Message::SerializePartialToOstream(ostream* output) const {
 }
 
 
+string Message::SerializeAsString() const {
+  // If the compiler implements the (Named) Return Value Optimization,
+  // the local variable 'result' will not actually reside on the stack
+  // of this function, but will be overlaid with the object that the
+  // caller supplied for the return value to be constructed in.
+  string output;
+  if (!AppendToString(&output))
+    output.clear();
+  return output;
+}
+
+string Message::SerializePartialAsString() const {
+  string output;
+  if (!AppendPartialToString(&output))
+    output.clear();
+  return output;
+}
+
 Reflection::~Reflection() {}
 
 // ===================================================================