Split ibmailutils/mailbox/message.c into logically separated and

easily manageable parts.

@@ -28,7 +28,27 @@ libmailbox_la_SOURCES =  \
  hdrfirst.c\
  hdritr.c\
  header.c\
- message.c\
- msgscan.c
+ msgcpy.c\
+ msgattr.c\
+ msgbody.c\
+ msgcreat.c\
+ msgheader.c\
+ msgenv.c\
+ msglines.c\
+ msgmbx.c\
+ msgmod.c\
+ msgmulti.c\
+ msgnumparts.c\
+ msgobs.c\
+ msgpart.c\
+ msgqid.c\
+ msgqlines.c\
+ msgref.c\
+ msgsave.c\
+ msgscan.c\
+ msgsize.c\
+ msgstream.c\
+ msguid.c\
+ msguidl.c
 
 INCLUDES = @MU_LIB_COMMON_INCLUDES@ -I/libmailutils

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/attribute.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_attribute (mu_message_t msg, mu_attribute_t *pattribute)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (pattribute == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+  if (msg->attribute == NULL)
+    {
+      mu_attribute_t attribute;
+      int status = mu_attribute_create (&attribute, msg);
+      if (status != 0)
+	return status;
+      msg->attribute = attribute;
+    }
+  *pattribute = msg->attribute;
+  return 0;
+}
+
+int
+mu_message_set_attribute (mu_message_t msg, mu_attribute_t attribute, void *owner)
+{
+  if (msg == NULL)
+   return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  if (msg->attribute)
+    mu_attribute_destroy (&msg->attribute, owner);
+  msg->attribute = attribute;
+  msg->flags |= MESSAGE_MODIFIED;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_body (mu_message_t msg, mu_body_t *pbody)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (pbody == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+
+  /* Is it a floating mesg.  */
+  if (msg->body == NULL)
+    {
+      mu_body_t body;
+      int status = mu_body_create (&body, msg);
+      if (status != 0)
+	return status;
+      /* If a stream is already set, use it to create the body stream.  */
+      /* FIXME: I'm not sure if the second condition is really needed */
+      if (msg->stream/* && (msg->flags & MESSAGE_INTERNAL_STREAM)*/)
+	{
+	  mu_stream_t stream;
+	  int flags = 0;
+
+	  /* FIXME: The actual mu_header_size cannot be used as offset,
+	     because the headers might have been modified in between. */
+	  
+	  mu_stream_get_flags (msg->stream, &flags);
+	  status = mu_streamref_create_abridged (&stream, msg->stream,
+						 msg->orig_header_size, 0);
+	  if (status)
+	    {
+	      mu_body_destroy (&body, msg);
+	      return status;
+	    }
+	  mu_body_set_stream (body, stream, msg);
+	}
+      msg->body = body;
+    }
+  *pbody = msg->body;
+  return 0;
+}
+
+int
+mu_message_set_body (mu_message_t msg, mu_body_t body, void *owner)
+{
+  if (msg == NULL )
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  /* Make sure we destroy the old if it was owned by the mesg.  */
+  /* FIXME:  I do not know if somebody has already a ref on this ? */
+  if (msg->body)
+    mu_body_destroy (&msg->body, msg);
+  msg->body = body;
+  msg->flags |= MESSAGE_MODIFIED;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_create_copy (mu_message_t *to, mu_message_t from)
+{
+  int status = 0;
+  mu_stream_t fromstr = NULL;
+  mu_stream_t tmp = NULL;
+
+  if (!to)
+    return MU_ERR_OUT_PTR_NULL;
+  if (!from)
+    return EINVAL;
+
+  status = mu_memory_stream_create (&tmp, MU_STREAM_RDWR|MU_STREAM_SEEK);
+  if (status)
+    return status;
+
+  status = mu_message_get_streamref (from, &fromstr);
+  if (status)
+    {
+      mu_stream_destroy (&tmp);
+      return status;
+    }
+
+  status = mu_stream_copy (tmp, fromstr, 0, NULL);
+  if (status == 0)
+    {
+      status = mu_message_create (to, NULL);
+      if (status == 0)
+	mu_message_set_stream (*to, tmp, NULL);
+    }
+
+  if (status)
+    mu_stream_destroy (&tmp);
+  mu_stream_destroy (&fromstr);
+
+  return status;
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+/*  Allocate ressources for the mu_message_t.  */
+int
+mu_message_create (mu_message_t *pmsg, void *owner)
+{
+  mu_message_t msg;
+  int status;
+
+  if (pmsg == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+  msg = calloc (1, sizeof (*msg));
+  if (msg == NULL)
+    return ENOMEM;
+  status = mu_monitor_create (&msg->monitor, 0, msg);
+  if (status != 0)
+    {
+      free (msg);
+      return status;
+    }
+  msg->owner = owner;
+  msg->ref_count = 1;
+  *pmsg = msg;
+  return 0;
+}
+
+void *
+mu_message_get_owner (mu_message_t msg)
+{
+  return (msg == NULL) ? NULL : msg->owner;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <sys/types.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <string.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/envelope.h>
+#include <mailutils/util.h>
+#include <mailutils/header.h>
+#include <mailutils/mu_auth.h>
+#include <mailutils/address.h>
+#include <mailutils/sys/message.h>
+
+/* Message envelope */
+static int
+message_envelope_date (mu_envelope_t envelope, char *buf, size_t len,
+		       size_t *pnwrite)
+{
+  mu_message_t msg = mu_envelope_get_owner (envelope);
+  time_t t;
+  size_t n;
+
+  if (msg == NULL)
+    return EINVAL;
+
+  /* FIXME: extract the time from "Date:".  */
+
+  if (buf == NULL || len == 0)
+    {
+      n = MU_ENVELOPE_DATE_LENGTH;
+    }
+  else
+    {
+      char tmpbuf[MU_ENVELOPE_DATE_LENGTH+1];
+      t = time (NULL);
+      n = mu_strftime (tmpbuf, sizeof tmpbuf, 
+                       MU_ENVELOPE_DATE_FORMAT, localtime (&t));
+      n = mu_cpystr (buf, tmpbuf, len);
+    }
+  if (pnwrite)
+    *pnwrite = n;
+  return 0;
+}
+
+static int
+message_envelope_sender (mu_envelope_t envelope, char *buf, size_t len,
+			 size_t *pnwrite)
+{
+  mu_message_t msg = mu_envelope_get_owner (envelope);
+  mu_header_t header;
+  int status;
+  const char *sender;
+  struct mu_auth_data *auth = NULL;
+  static char *hdrnames[] = {
+    "X-Envelope-Sender",
+    "X-Envelope-From",
+    "X-Original-Sender",
+    "From",
+    NULL
+  };
+  mu_address_t address = NULL;
+
+  if (msg == NULL)
+    return EINVAL;
+
+  /* First, try the header  */
+  status = mu_message_get_header (msg, &header);
+  if (status)
+    return status;
+  status = mu_header_sget_firstof (header, hdrnames, &sender, NULL);
+  if (status)
+    {
+      auth = mu_get_auth_by_uid (getuid ());
+      if (!auth)
+	return MU_ERR_NOENT;
+      sender = auth->name;
+    }
+
+  status = mu_address_create (&address, sender);
+  if (status == 0)
+    {
+      status = mu_address_sget_email (address, 1, &sender);
+      if (status == 0)
+	{
+	  size_t n = strlen (sender);
+	  if (buf && len > 0)
+	    {
+	      len--; /* One for the null.  */
+	      n = (n < len) ? n : len;
+	      memcpy (buf, sender, n);
+	      buf[n] = '\0';
+	    }
+	  if (pnwrite)
+	    *pnwrite = n;
+	}
+      mu_address_destroy (&address);
+    }
+  
+  if (auth)
+    mu_auth_data_free (auth);
+
+  return status;
+}
+
+int
+mu_message_get_envelope (mu_message_t msg, mu_envelope_t *penvelope)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (penvelope == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+
+  if (msg->envelope == NULL)
+    {
+      mu_envelope_t envelope;
+      int status = mu_envelope_create (&envelope, msg);
+      if (status != 0)
+	return status;
+      mu_envelope_set_sender (envelope, message_envelope_sender, msg);
+      mu_envelope_set_date (envelope, message_envelope_date, msg);
+      msg->envelope = envelope;
+    }
+  *penvelope = msg->envelope;
+  return 0;
+}
+
+int
+mu_message_set_envelope (mu_message_t msg, mu_envelope_t envelope, void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  if (msg->envelope)
+    mu_envelope_destroy (&msg->envelope, msg);
+  msg->envelope = envelope;
+  msg->flags |= MESSAGE_MODIFIED;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/message.h>
+
+
+enum eoh_state
+  {
+    eoh_no,
+    eoh_maybe,
+    eoh_yes
+  };
+
+/* Message header stuff */
+static enum eoh_state
+string_find_eoh (enum eoh_state eoh, const char *str, size_t len,
+		 size_t *ppos)
+{
+  size_t pos;
+
+  if (eoh == eoh_maybe && *str == '\n')
+    {
+      *ppos = 0;
+      return eoh_yes;
+    }
+  
+  for (pos = 0; pos < len - 1; pos++)
+    if (str[pos] == '\n' && str[pos + 1] == '\n')
+      {
+	*ppos = pos + 1;
+	return eoh_yes;
+      }
+  
+  *ppos = pos + 1;
+  return str[pos] == '\n' ? eoh_maybe : eoh_no;
+}
+
+#define MIN_HEADER_BUF_SIZE 2048
+
+static int
+_header_fill (mu_stream_t stream, char **pbuf, size_t *plen)
+{
+  int status = 0;
+  char *buffer = NULL;
+  size_t bufsize = 0;
+  char inbuf[MIN_HEADER_BUF_SIZE];
+  size_t nread;
+  enum eoh_state eoh = eoh_no;
+  
+  status = mu_stream_seek (stream, 0, MU_SEEK_SET, NULL);
+  if (status)
+    return status;
+      
+  while (eoh != eoh_yes
+	 && (status = mu_stream_read (stream, inbuf, sizeof (inbuf), &nread))
+	    == 0
+	 && nread)
+    {
+      char *nbuf;
+      size_t len;
+
+      eoh = string_find_eoh (eoh, inbuf, nread, &len);
+      
+      nbuf = realloc (buffer, bufsize + len);
+      if (!nbuf)
+	{
+	  status = ENOMEM;
+	  break;
+	}
+      memcpy (nbuf + bufsize, inbuf, len);
+      buffer = nbuf;
+      bufsize += len;
+    }
+
+  if (status)
+    free (buffer);
+  else
+    {
+      *pbuf = buffer;
+      *plen = bufsize;
+    }
+  return status;
+}
+
+static int
+message_header_fill (void *data, char **pbuf, size_t *plen)
+{
+  int status = 0;
+  mu_message_t msg = data;
+  mu_stream_t stream;
+
+  status = mu_message_get_streamref (msg, &stream);
+  if (status == 0)
+    {
+      status = _header_fill (stream, pbuf, plen);
+      mu_stream_destroy (&stream);
+    }
+  return status;
+}
+
+int
+mu_message_get_header (mu_message_t msg, mu_header_t *phdr)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (phdr == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+
+  if (msg->header == NULL)
+    {
+      mu_header_t header;
+      int status = mu_header_create (&header, NULL, 0);
+      if (status != 0)
+	return status;
+      if (msg->stream)
+	mu_header_set_fill (header, message_header_fill, msg);
+      status = mu_header_size (header, &msg->orig_header_size);
+      if (status)
+	return status;
+      msg->header = header;
+    }
+  *phdr = msg->header;
+  return 0;
+}
+
+/* Note: mu_message_set_header steals the reference to hdr */
+int
+mu_message_set_header (mu_message_t msg, mu_header_t hdr, void *owner)
+{
+  if (msg == NULL )
+    return EINVAL;
+  if (msg->owner != owner)
+     return EACCES;
+  if (msg->header)
+    mu_header_destroy (&msg->header);
+  msg->header = hdr;
+  msg->flags |= MESSAGE_MODIFIED;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_lines (mu_message_t msg, size_t *plines)
+{
+  size_t hlines, blines;
+  int ret = 0;
+
+  if (msg == NULL)
+    return EINVAL;
+  /* Overload.  */
+  if (msg->_lines)
+    return msg->_lines (msg, plines, 0);
+  if (plines)
+    {
+      mu_header_t hdr = NULL;
+      mu_body_t body = NULL;
+
+      hlines = blines = 0;
+      mu_message_get_header (msg, &hdr);
+      mu_message_get_body (msg, &body);
+      if ( ( ret = mu_header_lines (hdr, &hlines) ) == 0 )
+	      ret = mu_body_lines (body, &blines);
+      *plines = hlines + blines;
+    }
+  return ret;
+}
+
+int
+mu_message_set_lines (mu_message_t msg, int (*_lines)
+		      (mu_message_t, size_t *, int), void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_lines = _lines;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_mailbox (mu_message_t msg, mu_mailbox_t *pmailbox)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (pmailbox == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+  *pmailbox = msg->mailbox;
+  return 0;
+}
+
+int
+mu_message_set_mailbox (mu_message_t msg, mu_mailbox_t mailbox, void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->mailbox = mailbox;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/attribute.h>
+#include <mailutils/body.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_is_modified (mu_message_t msg)
+{
+  int mod = 0;
+  if (msg)
+    {
+      if (mu_header_is_modified (msg->header))
+	mod |= MU_MSG_HEADER_MODIFIED;
+      if (mu_attribute_is_modified (msg->attribute))
+	mod |= MU_MSG_ATTRIBUTE_MODIFIED;
+      if (mu_body_is_modified (msg->body))
+	mod |= MU_MSG_BODY_MODIFIED;
+      if (msg->flags & MESSAGE_MODIFIED)
+	mod |= MU_MSG_BODY_MODIFIED | MU_MSG_HEADER_MODIFIED;
+    }
+  return mod;
+}
+
+int
+mu_message_clear_modified (mu_message_t msg)
+{
+  if (msg)
+    {
+      if (msg->header)
+	mu_header_clear_modified (msg->header);
+      if (msg->attribute)
+	mu_attribute_clear_modified (msg->attribute);
+      if (msg->body)
+	mu_body_clear_modified (msg->body);
+      msg->flags &= ~MESSAGE_MODIFIED;
+    }
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/mime.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_is_multipart (mu_message_t msg, int *pmulti)
+{
+  if (msg && pmulti)
+    {
+      if (msg->_is_multipart)
+	return msg->_is_multipart (msg, pmulti);
+      if (msg->mime == NULL)
+	{
+	  int status = mu_mime_create (&msg->mime, msg, 0);
+	  if (status != 0)
+	    return 0;
+	  msg->flags |= MESSAGE_MIME_OWNER;
+	}
+      *pmulti = mu_mime_is_multipart(msg->mime);
+    }
+  return 0;
+}
+
+int
+mu_message_set_is_multipart (mu_message_t msg,
+			     int (*_is_multipart) (mu_message_t, int *),
+			     void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_is_multipart = _is_multipart;
+  return 0;
+}
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/mime.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_num_parts (mu_message_t msg, size_t *pparts)
+{
+  if (msg == NULL || pparts == NULL)
+    return EINVAL;
+
+  if (msg->_get_num_parts)
+    return msg->_get_num_parts (msg, pparts);
+
+  if (msg->mime == NULL)
+    {
+      int status = mu_mime_create (&msg->mime, msg, 0);
+      if (status != 0)
+	return status;
+    }
+  return mu_mime_get_num_parts (msg->mime, pparts);
+}
+
+int
+mu_message_set_get_num_parts (mu_message_t msg,
+			   int (*_get_num_parts) (mu_message_t, size_t *),
+			   void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_num_parts = _get_num_parts;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/observer.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_observable (mu_message_t msg, mu_observable_t *pobservable)
+{
+  if (msg == NULL || pobservable == NULL)
+    return EINVAL;
+
+  if (msg->observable == NULL)
+    {
+      int status = mu_observable_create (&msg->observable, msg);
+      if (status != 0)
+	return status;
+    }
+  *pobservable = msg->observable;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_part (mu_message_t msg, size_t part, mu_message_t *pmsg)
+{
+  if (msg == NULL || pmsg == NULL)
+    return EINVAL;
+
+  /* Overload.  */
+  if (msg->_get_part)
+    return msg->_get_part (msg, part, pmsg);
+
+  if (msg->mime == NULL)
+    {
+      int status = mu_mime_create (&msg->mime, msg, 0);
+      if (status != 0)
+	return status;
+    }
+  return mu_mime_get_part (msg->mime, part, pmsg);
+}
+
+int
+mu_message_set_get_part (mu_message_t msg, int (*_get_part)
+		      (mu_message_t, size_t, mu_message_t *),
+		      void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_part = _get_part;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_qid (mu_message_t msg, mu_message_qid_t *pqid)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (!msg->_get_qid)
+    return ENOSYS;
+  return msg->_get_qid (msg, pqid);
+}
+    
+int
+mu_message_set_qid (mu_message_t msg,
+		    int (*_get_qid) (mu_message_t, mu_message_qid_t *),
+		    void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_qid = _get_qid;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/sys/message.h>
+
+/* Return the number of lines in the message, without going into
+   excess trouble for calculating it.  If obtaining the result
+   means downloading the entire message (as is the case for POP3,
+   for example), return MU_ERR_INFO_UNAVAILABLE. */
+int
+mu_message_quick_lines (mu_message_t msg, size_t *plines)
+{
+  size_t hlines, blines;
+  int rc;
+  
+  if (msg == NULL)
+    return EINVAL;
+  /* Overload.  */
+  if (msg->_lines)
+    {
+      int rc = msg->_lines (msg, plines, 1);
+      if (rc != ENOSYS)
+	return rc;
+    }
+  if (plines)
+    {
+      mu_header_t hdr = NULL;
+      mu_body_t body = NULL;
+
+      hlines = blines = 0;
+      mu_message_get_header (msg, &hdr);
+      mu_message_get_body (msg, &body);
+      if ((rc = mu_header_lines (hdr, &hlines)) == 0)
+	rc = mu_body_lines (body, &blines);
+      if (rc == 0)
+	*plines = hlines + blines;
+    }
+  return rc;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/monitor.h>
+#include <mailutils/observer.h>
+#include <mailutils/envelope.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/attribute.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/message.h>
+
+void
+mu_message_ref (mu_message_t msg)
+{
+  if (msg)
+    {
+      mu_monitor_wrlock (msg->monitor);
+      msg->ref_count++;
+      mu_monitor_unlock (msg->monitor);
+    }
+}
+
+/* Free the message and all associated stuff */
+static void
+_mu_message_free (mu_message_t msg)
+{
+  /* Notify the listeners.  */
+  /* FIXME: to be removed since we do not support this event.  */
+  if (msg->observable)
+    {
+      mu_observable_notify (msg->observable, MU_EVT_MESSAGE_DESTROY, msg);
+      mu_observable_destroy (&msg->observable, msg);
+    }
+      
+  /* Envelope.  */
+  if (msg->envelope)
+    mu_envelope_destroy (&msg->envelope, msg);
+      
+  /* Header.  */
+  if (msg->header)
+    mu_header_destroy (&msg->header);
+      
+  /* Body.  */
+  if (msg->body)
+    mu_body_destroy (&msg->body, msg);
+      
+  /* Attribute.  */
+  if (msg->attribute)
+    mu_attribute_destroy (&msg->attribute, msg);
+      
+  /* Stream.  */
+  if (msg->stream)
+    mu_stream_destroy (&msg->stream);
+      
+  /*  Mime.  */
+  if (msg->flags & MESSAGE_MIME_OWNER)
+    mu_mime_destroy (&msg->mime);
+      
+  /* Loose the owner.  */
+  msg->owner = NULL;
+      
+  free (msg);
+}
+
+void
+mu_message_unref (mu_message_t msg)
+{
+  if (msg)
+    {
+      mu_monitor_t monitor = msg->monitor;
+      mu_monitor_wrlock (monitor);
+      /* Note: msg->ref may be incremented by mu_message_ref without
+	 additional checking for its owner, therefore decrementing
+	 it must also occur independently of the owner checking. Due
+	 to this inconsistency ref may reach negative values, which
+	 is very unfortunate.
+	 
+	 The `owner' stuff is a leftover from older mailutils versions.
+	 We are heading to removing it altogether. */
+      if (msg->ref_count > 0)
+	msg->ref_count--;
+      if (msg->ref_count == 0)
+	{
+	  _mu_message_free (msg);
+	  mu_monitor_unlock (monitor);
+	  mu_monitor_destroy (&monitor, msg);
+	}
+      else
+	mu_monitor_unlock (monitor);
+    }
+}
+
+void
+mu_message_destroy (mu_message_t *pmsg, void *owner)
+{
+  if (pmsg && *pmsg)
+    {
+      mu_message_t msg = *pmsg;
+      
+      mu_monitor_t monitor = msg->monitor;
+      mu_monitor_wrlock (monitor);
+
+      if (msg->owner && msg->owner == owner)
+	{
+	  _mu_message_free (msg);
+	  mu_monitor_unlock (monitor);
+	  mu_monitor_destroy (&monitor, msg);
+	  *pmsg = NULL;
+	  return;
+	}
+      mu_monitor_unlock (monitor);
+    }
+}
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include <mailutils/types.h>
+#include <mailutils/diag.h>
+#include <mailutils/error.h>
+#include <mailutils/errno.h>
+#include <mailutils/mailbox.h>
+#include <mailutils/message.h>
+#include <mailutils/stream.h>
+
+int
+mu_message_save_to_mailbox (mu_message_t msg, const char *toname, int perms)
+{
+  int rc = 0;
+  mu_mailbox_t to = 0;
+
+  if ((rc = mu_mailbox_create_default (&to, toname)))
+    {
+      mu_debug (MU_DEBCAT_MESSAGE, MU_DEBUG_ERROR, 		 
+		("mu_mailbox_create_default (%s) failed: %s\n", toname,
+		 mu_strerror (rc)));
+      goto end;
+    }
+
+  if ((rc = mu_mailbox_open (to,
+			     MU_STREAM_WRITE | MU_STREAM_CREAT
+			     | (perms & MU_STREAM_IMASK))))
+    {
+      mu_debug (MU_DEBCAT_MESSAGE, MU_DEBUG_ERROR, 		 
+		("mu_mailbox_open (%s) failed: %s", toname,
+		 mu_strerror (rc)));
+      goto end;
+    }
+
+  if ((rc = mu_mailbox_append_message (to, msg)))
+    {
+      mu_debug (MU_DEBCAT_MESSAGE, MU_DEBUG_ERROR, 		 
+		("mu_mailbox_append_message (%s) failed: %s", toname,
+		 mu_strerror (rc)));
+      goto end;
+    }
+
+end:
+
+  if (!rc)
+    {
+      if ((rc = mu_mailbox_close (to)))
+        mu_debug (MU_DEBCAT_MESSAGE, MU_DEBUG_ERROR, 		 
+		  ("mu_mailbox_close (%s) failed: %s", toname,
+		   mu_strerror (rc)));
+    }
+  else
+    mu_mailbox_close (to);
+
+  mu_mailbox_destroy (&to);
+
+  return rc;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_size (mu_message_t msg, size_t *psize)
+{
+  size_t hsize, bsize;
+  int ret = 0;
+
+  if (msg == NULL)
+    return EINVAL;
+  /* Overload ? */
+  if (msg->_size)
+    return msg->_size (msg, psize);
+  if (psize)
+    {
+      mu_header_t hdr = NULL;
+      mu_body_t body = NULL;
+      
+      hsize = bsize = 0;
+      mu_message_get_header (msg, &hdr);
+      mu_message_get_body (msg, &body);
+      if ( ( ret = mu_header_size (hdr, &hsize) ) == 0 )
+	ret = mu_body_size (body, &bsize);
+      *psize = hsize + bsize;
+    }
+  return ret;
+}
+
+int
+mu_message_set_size (mu_message_t msg, int (*_size)
+		     (mu_message_t, size_t *), void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_size = _size;
+  return 0;
+}
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/stream.h>
+#include <mailutils/header.h>
+#include <mailutils/body.h>
+#include <mailutils/sys/message.h>
+#include <mailutils/sys/stream.h>
+
+/* Message stream */
+
+enum _message_stream_state
+  {
+    _mss_init,
+    _mss_header,
+    _mss_body,
+    _mss_eof
+  };
+
+struct _mu_message_stream
+{
+  struct _mu_stream stream;
+  mu_message_t msg;
+  enum _message_stream_state state;
+  mu_stream_t transport;
+  mu_off_t limit;
+};
+
+static int
+_check_stream_state (struct _mu_message_stream *str)
+{
+  int rc = 0;
+  
+  if (str->transport && mu_stream_eof (str->transport))
+    mu_stream_destroy (&str->transport);
+  
+  switch (str->state)
+    {
+    case _mss_init:
+      if (!str->transport)
+	{
+	  rc = mu_header_get_streamref (str->msg->header, &str->transport);
+	  if (rc == 0)
+	    {
+	      str->state = _mss_header;
+	      rc = mu_stream_seek (str->transport, 0, MU_SEEK_SET, NULL);
+	    }
+	}
+      break;
+      
+    case _mss_header:
+      if (!str->transport)
+	{
+	  rc = mu_body_get_streamref (str->msg->body, &str->transport);
+	  if (rc == 0)
+	    {
+	      str->state = _mss_body;
+	      rc = mu_stream_seek (str->transport, 0, MU_SEEK_SET, NULL);
+	    }
+	}
+      break;
+      
+    case _mss_body:
+      if (!str->transport)
+	str->state = _mss_eof;
+    case _mss_eof:
+      break;
+    }
+  return rc;
+}
+
+static void
+_message_stream_done (struct _mu_stream *str)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  mu_stream_destroy (&sp->transport);
+}
+
+static int
+_message_stream_flush (struct _mu_stream *str)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  int rc = _check_stream_state (sp);
+  if (rc)
+    return rc;
+  return mu_stream_flush (sp->transport);
+}
+  
+static int
+_message_stream_size (struct _mu_stream *str, mu_off_t *psize)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  size_t hsize, bsize;
+  mu_header_size (sp->msg->header, &hsize);
+  mu_body_size (sp->msg->body, &bsize);
+  if (psize)
+    *psize = hsize + bsize;
+  return 0;
+}
+
+static int
+_message_stream_seek (struct _mu_stream *str, mu_off_t off, mu_off_t *ppos)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  size_t hsize, size;
+  int rc;
+  
+  rc = _check_stream_state (sp);
+  if (rc)
+    return rc;
+  mu_header_size (sp->msg->header, &hsize);
+  mu_body_size (sp->msg->body, &size);
+  
+  if (off < 0 || off >= size + hsize)
+    return ESPIPE;
+
+  switch (sp->state)
+    {
+    case _mss_eof:
+      sp->state = _mss_init;
+      rc = _check_stream_state (sp);
+      if (rc)
+	return rc;
+      /* fall through */
+    case _mss_header:
+      if (off < hsize)
+	break;
+      mu_stream_destroy (&sp->transport);
+      rc = _check_stream_state (sp);
+      if (rc)
+	return rc;
+      /* fall through */
+    case _mss_body:
+      if (off > hsize)
+	off -= hsize;	
+      else
+	{
+	  mu_stream_destroy (&sp->transport);
+	  sp->state = _mss_init;
+	  rc = _check_stream_state (sp);
+	  if (rc)
+	    return rc;
+	}
+
+      break;
+
+    default:
+      break;
+    }
+  rc = mu_stream_seek (sp->transport, off, MU_SEEK_SET, &off);
+  if (rc == 0)
+    {
+      if (sp->state == _mss_body)
+	off += hsize;
+      *ppos = off;
+    }
+  return rc;
+}
+
+static int
+_message_stream_read (struct _mu_stream *str, char *buf, size_t bufsize,
+		      size_t *pnread)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  size_t nread = 0;
+  int rc;
+  
+  while (bufsize)
+    {
+      size_t n;
+      rc = _check_stream_state (sp);
+      if (rc)
+	break;
+      if (sp->state == _mss_eof)
+	break;
+      rc = mu_stream_read (sp->transport, buf, bufsize, &n);
+      if (rc)
+	break;
+      if (n == 0)
+	continue;
+      nread += n;
+      buf += n;
+      bufsize -= n;
+    }
+  *pnread = nread;
+  return rc;
+}
+
+static int
+_message_stream_readdelim (struct _mu_stream *str, char *buf, size_t bufsize,
+			   int delim, size_t *pnread)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  size_t nread = 0;
+  int rc;
+  
+  while (bufsize)
+    {
+      size_t n;
+      rc = _check_stream_state (sp);
+      if (rc)
+	break;
+      if (sp->state == _mss_eof)
+	break;
+      rc = mu_stream_readdelim (sp->transport, buf, bufsize, delim, &n);
+      if (rc)
+	break;
+      if (n == 0)
+	continue;
+      nread += n;
+      if (buf[n-1] == delim)
+	break;
+      buf += n;
+      bufsize -= n;
+    }
+  *pnread = nread;
+  return rc;
+}  
+
+#if 0
+static int
+_message_stream_write (struct _mu_stream *str,
+		       const char *buf, size_t bufsize,
+		       size_t *pnwritten)
+{
+  struct _mu_message_stream *sp = (struct _mu_message_stream *)str;
+  
+  /* FIXME */
+}
+#endif
+
+static int
+_message_stream_create (mu_stream_t *pmsg, mu_message_t msg, int flags)
+{
+  struct _mu_message_stream *sp;
+
+  sp = (struct _mu_message_stream *) _mu_stream_create (sizeof (*sp),
+							flags |
+							MU_STREAM_SEEK |
+							_MU_STR_OPEN);
+  if (!sp)
+    return ENOMEM;
+
+  sp->stream.read = _message_stream_read;
+  sp->stream.readdelim = _message_stream_readdelim;
+  /* FIXME: Write is not defined */
+  /*  sp->stream.write = _message_stream_write;*/
+  sp->stream.done = _message_stream_done;
+  sp->stream.flush = _message_stream_flush;
+  sp->stream.seek = _message_stream_seek; 
+  sp->stream.size = _message_stream_size;
+  sp->state = _mss_init;
+  sp->msg = msg;
+  *pmsg = (mu_stream_t) sp;
+  return 0;
+}
+
+int
+mu_message_set_stream (mu_message_t msg, mu_stream_t stream, void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  if (msg->stream)
+    mu_stream_destroy (&msg->stream);
+  msg->stream = stream;
+  msg->flags |= MESSAGE_MODIFIED;
+  msg->flags &= ~MESSAGE_INTERNAL_STREAM;
+  return 0;
+}
+
+static int
+_message_get_stream (mu_message_t msg, mu_stream_t *pstream, int ref)
+{
+  int status;
+
+  if (msg == NULL)
+    return EINVAL;
+  if (pstream == NULL)
+    return MU_ERR_OUT_PTR_NULL;
+
+  if (msg->stream == NULL)
+    {
+      if (msg->_get_stream)
+	{
+	  status = msg->_get_stream (msg, &msg->stream);
+	  if (status)
+	    return status;
+	}
+      else
+	{
+	  mu_header_t hdr;
+	  mu_body_t body;
+
+	  /* FIXME: Kind of a kludge: make sure the message has header
+	     and body initialized. */
+	  status = mu_message_get_header (msg, &hdr);
+	  if (status)
+	    return status;
+	  status = mu_message_get_body (msg, &body);
+	  if (status)
+	    return status;
+	  
+	  status = _message_stream_create (&msg->stream, msg, MU_STREAM_RDWR);
+	  if (status)
+	    return status;
+	  msg->flags |= MESSAGE_INTERNAL_STREAM;
+	}
+    }
+  
+  if (!ref)
+    {
+      *pstream = msg->stream;
+      return 0;
+    }
+  return mu_streamref_create (pstream, msg->stream);
+}
+
+int
+mu_message_get_stream (mu_message_t msg, mu_stream_t *pstream)
+{
+  /* FIXME: Deprecation warning */
+  return _message_get_stream (msg, pstream, 0);
+}
+
+int
+mu_message_get_streamref (mu_message_t msg, mu_stream_t *pstream)
+{
+  return _message_get_stream (msg, pstream, 1);
+}
+
+int
+mu_message_set_get_stream (mu_message_t msg,
+			   int (*_getstr) (mu_message_t, mu_stream_t *),
+			   void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_stream = _getstr;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_uid (mu_message_t msg, size_t *puid)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->_get_uid)
+    return msg->_get_uid (msg, puid);
+  *puid = 0;
+  return 0;
+}
+
+int
+mu_message_set_uid (mu_message_t msg, int (*_get_uid) (mu_message_t, size_t *),
+		    void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_uid = _get_uid;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2009,
+   2010, 2011 Free Software Foundation, Inc.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 3 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General
+   Public License along with this library.  If not, see
+   <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <time.h>
+#include <string.h>
+#include <mailutils/types.h>
+#include <mailutils/message.h>
+#include <mailutils/errno.h>
+#include <mailutils/header.h>
+#include <mailutils/stream.h>
+#include <mailutils/md5.h>
+#include <mailutils/sys/message.h>
+
+int
+mu_message_get_uidl (mu_message_t msg, char *buffer, size_t buflen,
+		     size_t *pwriten)
+{
+  mu_header_t header = NULL;
+  size_t n = 0;
+  int status;
+
+  if (msg == NULL || buffer == NULL || buflen == 0)
+    return EINVAL;
+
+  buffer[0] = '\0';
+  /* Try the function overload if error fallback.  */
+  if (msg->_get_uidl)
+    {
+      status = msg->_get_uidl (msg, buffer, buflen, pwriten);
+      if (status == 0)
+	return status;
+    }
+
+  /* Be compatible with Qpopper ? qppoper saves the UIDL in "X-UIDL".
+     We generate a chksum and save it in the header.  */
+  mu_message_get_header (msg, &header);
+  status = mu_header_get_value_unfold (header, "X-UIDL", buffer, buflen, &n);
+  if (status != 0 || n == 0)
+    {
+      size_t uid = 0;
+      struct mu_md5_ctx md5context;
+      mu_stream_t stream = NULL;
+      char buf[1024];
+      unsigned char md5digest[16];
+      char *tmp;
+      n = 0;
+      mu_message_get_uid (msg, &uid);
+      mu_message_get_streamref (msg, &stream);
+      mu_md5_init_ctx (&md5context);
+      status = mu_stream_seek (stream, 0, MU_SEEK_SET, NULL);
+      if (status == 0)
+	{
+	  while (mu_stream_read (stream, buf, sizeof (buf), &n) == 0
+		 && n > 0)
+	    mu_md5_process_bytes (buf, n, &md5context);
+	  mu_md5_finish_ctx (&md5context, md5digest);
+	  tmp = buf;
+	  for (n = 0; n < 16; n++, tmp += 2)
+	    sprintf (tmp, "%02x", md5digest[n]);
+	  *tmp = '\0';
+	  /* POP3 rfc says that an UID should not be longer than 70.  */
+	  snprintf (buf + 32, 70, ".%lu.%lu", (unsigned long)time (NULL), 
+		    (unsigned long) uid);
+
+	  mu_header_set_value (header, "X-UIDL", buf, 1);
+	  buflen--; /* leave space for the NULL.  */
+	  strncpy (buffer, buf, buflen)[buflen] = '\0';
+	}
+      mu_stream_destroy (&stream);
+    }
+  return status;
+}
+
+int
+mu_message_set_uidl (mu_message_t msg,
+		  int (* _get_uidl) (mu_message_t, char *, size_t, size_t *),
+		  void *owner)
+{
+  if (msg == NULL)
+    return EINVAL;
+  if (msg->owner != owner)
+    return EACCES;
+  msg->_get_uidl = _get_uidl;
+  return 0;
+}