~drizzle-trunk/drizzle/development

#include "config.h"

#include "binary_log.h"

#include <google/protobuf/io/coded_stream.h>

using namespace google::protobuf;

using namespace google::protobuf::io;

bool

BinaryLog::Event::write(CodedOutputStream* out) const

{

  // We frame each event in a length encoded in a special manner, and

  // end it with a CRC-32 checksum.

  // Write length and type

  unsigned char buf[LENGTH_ENCODE_MAX_BYTES + 1];

  unsigned char *end= length_encode(m_message->ByteSize(), buf);

  *end++= m_type;

  char cs[4] = { 0 };                           // !!! No checksum yet

  if (!out->WriteRaw(buf, end - buf) ||         // Length + Type

      !m_message->SerializeToCodedStream(out) || // Event body

      !out->WriteRaw(cs, sizeof(cs)))           // Checksum

    return false;

  return true;

}

bool

BinaryLog::Event::read(CodedInputStream *in)

{

  unsigned char buf[LENGTH_ENCODE_MAX_BYTES + 1];

  // Read length peek byte to figure out length

  if (!in->ReadRaw(buf, 1))

    return false;

  // Read in the rest of the length bytes plus the type

  size_t bytes= length_decode_bytes(*buf);

  if (!in->ReadRaw(buf + 1, bytes))

    return false;

  size_t length;

  (void) length_decode(buf, &length);

  // Fetch type from read buffer

  m_type= static_cast<EventType>(buf[bytes]);

  // Create the right event based on the type code (is there something

  // better in the protobuf library?)

  Message *message= NULL;

  switch (m_type) {

  case QUERY:

    message= new BinaryLog::Query;

    break;

  case COMMIT:

    message= new BinaryLog::Commit;

    break;

  case ROLLBACK:

    message= new BinaryLog::Rollback;

    break;

  case START:

    message= new BinaryLog::Start;

    break;

  case CHAIN:

    message= new BinaryLog::Chain;

    break;

  }

  if (!message)

    return false;

  // Read the event body as length bytes. It is necessary to limit the

  // stream since otherwise ParseFromCodedStream reads all bytes of

  // the stream.

  CodedInputStream::Limit limit= in->PushLimit(length);

  if (!message->ParseFromCodedStream(in))

    return false;

  in->PopLimit(limit);

  delete m_message;

  m_message= message;

  // Read checksum (none here yet)

  char checksum[4];

  if (!in->ReadRaw(checksum, sizeof(checksum)))

    return false;

  return true;

}

template <class EventClass>

void print_common(std::ostream& out, EventClass* event)

{

  out << "# Global Id: (" << event->header().server_id() << "," << event->header().trans_id() << ")\n";

}

void

BinaryLog::Event::print(std::ostream& out) const

{

  using namespace google::protobuf;

  switch (m_type) {

  case QUERY:

  {

    Query *event= static_cast<Query*>(m_message);

    print_common(out, event);

    for (RepeatedPtrField<Query::Variable>::const_iterator ii= event->variable().begin() ;

         ii != event->variable().end() ;

         ++ii)

    {

      out << "set @" << ii->name() << " = '" << ii->value() << "'\n";

    }

    out << event->query() << std::endl;

    break;

  }

  case COMMIT:

  {

    Commit *event= static_cast<Commit*>(m_message);

    print_common(out, event);

    // NYI !!!

    break;

  }

  case ROLLBACK:

  {

    Rollback *event= static_cast<Rollback*>(m_message);

    print_common(out, event);

    // NYI !!!

    break;

  }

  case START:

  {

    Start *event= static_cast<Start*>(m_message);

    print_common(out, event);

    // NYI !!!

    break;

  }

  case CHAIN:

  {

    Chain *event= static_cast<Chain*>(m_message);

    print_common(out, event);

    // NYI !!!

    break;

  }

  default:

    break;                                      /* Nothing */

  }

}