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#include "util/protobuf_util.h"
#include <google/protobuf/io/coded_stream.h>
#include <google/protobuf/io/zero_copy_stream_impl.h>
#include <google/protobuf/message.h>
namespace cert_trans {
using google::protobuf::MessageLite;
using google::protobuf::io::CodedOutputStream;
using google::protobuf::io::OstreamOutputStream;
using google::protobuf::io::ZeroCopyOutputStream;
// Implements the MessageLite.writeDelimitedTo() method from the Java proto
// API, which is strangely absent from the C++ library.
// This code was pinched from a response by Kenton Varda (ex Protobuf
// developer) to a question about this topic here:
// http://stackoverflow.com/a/22927149
bool WriteDelimitedTo(const MessageLite& message,
ZeroCopyOutputStream* rawOutput) {
// We create a new coded stream for each message. Don't worry, this is fast.
CodedOutputStream output(rawOutput);
// Write the size.
const int size = message.ByteSize();
output.WriteVarint32(size);
uint8_t* buffer = output.GetDirectBufferForNBytesAndAdvance(size);
if (buffer != NULL) {
// Optimization: The message fits in one buffer, so use the faster
// direct-to-array serialization path.
message.SerializeWithCachedSizesToArray(buffer);
} else {
// Slightly-slower path when the message is multiple buffers.
message.SerializeWithCachedSizes(&output);
if (output.HadError())
return false;
}
return true;
}
bool WriteDelimitedToOstream(const MessageLite& message, std::ostream* os) {
OstreamOutputStream oos(os);
return WriteDelimitedTo(message, &oos);
}
} // namespace cert_trans
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