/* Copyright (c) 2013-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"

#include "istream.h"

#include "ostream-private.h"

#include "ostream-metawrap.h"

struct metawrap_ostream {

  struct ostream_private ostream;

  void (*write_callback)(void *);

  void *context;

};

static void o_stream_metawrap_call_callback(struct metawrap_ostream *mstream)

{

  void (*write_callback)(void *) = mstream->write_callback;

  if (write_callback != NULL) {

    mstream->write_callback = NULL;

    write_callback(mstream->context);

    /* metadata headers aren't counted as part of the offset */

    mstream->ostream.ostream.offset = 0;

  }

}

static ssize_t

o_stream_metawrap_sendv(struct ostream_private *stream,

      const struct const_iovec *iov, unsigned int iov_count)

{

  struct metawrap_ostream *mstream = (struct metawrap_ostream *)stream;

  ssize_t ret;

  o_stream_metawrap_call_callback(mstream);

  if ((ret = o_stream_sendv(stream->parent, iov, iov_count)) < 0)

    o_stream_copy_error_from_parent(stream);

  else

    stream->ostream.offset += ret;

  return ret;

}

static enum ostream_send_istream_result

o_stream_metawrap_send_istream(struct ostream_private *_outstream,

             struct istream *instream)

{

  struct metawrap_ostream *outstream =

    (struct metawrap_ostream *)_outstream;

  uoff_t orig_instream_offset = instream->v_offset;

  enum ostream_send_istream_result res;

  o_stream_metawrap_call_callback(outstream);

  if ((res = o_stream_send_istream(_outstream->parent, instream)) == OSTREAM_SEND_ISTREAM_RESULT_ERROR_OUTPUT)

    o_stream_copy_error_from_parent(_outstream);

  _outstream->ostream.offset += instream->v_offset - orig_instream_offset;

  return res;

}

struct ostream *

o_stream_create_metawrap(struct ostream *output,

       void (*write_callback)(void *), void *context)

{

  struct metawrap_ostream *mstream;

  mstream = i_new(struct metawrap_ostream, 1);

  mstream->ostream.sendv = o_stream_metawrap_sendv;

  mstream->ostream.send_istream = o_stream_metawrap_send_istream;

  mstream->write_callback = write_callback;

  mstream->context = context;

  return o_stream_create(&mstream->ostream, output,

             o_stream_get_fd(output));

}