Fix compilation of libmu_scm.

* libmu_scm/mu_body.c (mu_scm_body_free): Unref the stream.
Return 0.
(mu-body-read-line, mu-body-write): Use stringrefs.
* libmu_scm/mu_mailbox.c (mu-mailbox-get-port): Use stringrefs.
* libmu_scm/mu_message.c (mu-message-copy): Use stringrefs.
Use mu_stream_copy instead of manually copying stream contents.
(mu-message-get-port): Use stringrefs.
* libmu_scm/mu_port.c (mu_port_free): Unref the stream.

@@ -47,8 +47,9 @@ mu_scm_body_free (SCM body_smob)
   struct mu_body *mbp = (struct mu_body *) SCM_CDR (body_smob);
   if (mbp->buffer)
     free (mbp->buffer);
+  mu_stream_unref (mbp->stream);
   free (mbp);
-  return sizeof (struct mu_body);
+  return 0;
 }
 
 static int
@@ -114,7 +115,7 @@ SCM_DEFINE_PUBLIC (scm_mu_body_read_line, "mu-body-read-line", 1, 0, 0,
 
   if (!mbp->stream)
     {
-      status = mu_body_get_stream (mbp->body, &mbp->stream);
+      status = mu_body_get_streamref (mbp->body, &mbp->stream);
       if (status)
 	mu_scm_error (FUNC_NAME, status,
 		      "Cannot get body stream",
@@ -158,7 +159,7 @@ SCM_DEFINE_PUBLIC (scm_mu_body_write, "mu-body-write", 2, 0, 0,
   
   if (!mbp->stream)
     {
-      status = mu_body_get_stream (mbp->body, &mbp->stream);
+      status = mu_body_get_streamref (mbp->body, &mbp->stream);
       if (status)
 	mu_scm_error (FUNC_NAME, status,
 		      "Cannot get body stream", SCM_BOOL_F);

@@ -316,7 +316,7 @@ SCM_DEFINE_PUBLIC (scm_mu_mailbox_get_port, "mu-mailbox-get-port", 2, 0, 0,
   SCM_ASSERT (mu_scm_is_mailbox (mbox), mbox, SCM_ARG1, FUNC_NAME);
   SCM_ASSERT (scm_is_string (mode), mode, SCM_ARG2, FUNC_NAME);
   mum = (struct mu_mailbox *) SCM_CDR (mbox);
-  status = mu_mailbox_get_stream (mum->mbox, &stream);
+  status = mu_mailbox_get_streamref (mum->mbox, &stream);
   if (status)
     mu_scm_error (FUNC_NAME, status,
 		  "Cannot get mailbox stream",

@@ -195,14 +195,12 @@ SCM_DEFINE_PUBLIC (scm_mu_message_copy, "mu-message-copy", 1, 0, 0,
 {
   mu_message_t msg, newmsg;
   mu_stream_t in = NULL, out = NULL;
-  char buffer[512];
-  size_t n;
   int status;
   
   SCM_ASSERT (mu_scm_is_message (mesg), mesg, SCM_ARG1, FUNC_NAME);
   msg = mu_scm_message_get (mesg);
 
-  status = mu_message_get_stream (msg, &in);
+  status = mu_message_get_streamref (msg, &in);
   if (status)
     mu_scm_error (FUNC_NAME, status,
 		  "Cannot get input stream from message ~A",
@@ -213,7 +211,7 @@ SCM_DEFINE_PUBLIC (scm_mu_message_copy, "mu-message-copy", 1, 0, 0,
     mu_scm_error (FUNC_NAME, status,
 		  "Cannot create message", SCM_BOOL_F);
   
-  status = mu_message_get_stream (newmsg, &out);
+  status = mu_message_get_streamref (newmsg, &out);
   if (status)
     {
       mu_message_destroy (&newmsg, NULL);
@@ -221,18 +219,14 @@ SCM_DEFINE_PUBLIC (scm_mu_message_copy, "mu-message-copy", 1, 0, 0,
 		    "Cannot get output stream", SCM_BOOL_F);
     }
 
-  mu_stream_seek (in, 0, MU_SEEK_SET, NULL);
-  while ((status = mu_stream_read (in, buffer, sizeof (buffer) - 1, &n))
-	 == 0
-	 && n != 0)
+  status = mu_stream_copy (out, in, 0);
+  mu_stream_destroy (&in);
+  mu_stream_destroy (&out);
+  if (status)
     {
-      status = mu_stream_write (out, buffer, n, NULL);
-      if (status)
-	{
-	  mu_message_destroy (&newmsg, NULL);
-	  mu_scm_error (FUNC_NAME, status,
-			"Error writing to stream", SCM_BOOL_F);
-	}
+      mu_message_destroy (&newmsg, NULL);
+      mu_scm_error (FUNC_NAME, status,
+		    "Error writing to stream", SCM_BOOL_F);
     }
   
   return mu_scm_message_create (SCM_BOOL_F, newmsg);
@@ -905,7 +899,7 @@ SCM_DEFINE_PUBLIC (scm_mu_message_get_port, "mu-message-get-port", 2, 1, 0,
       SCM_ASSERT (scm_is_bool (full), full, SCM_ARG3, FUNC_NAME);
       if (full == SCM_BOOL_T)
 	{
-	  status = mu_message_get_stream (msg, &stream);
+	  status = mu_message_get_streamref (msg, &stream);
 	  if (status)
 	    mu_scm_error (FUNC_NAME, status, "Cannot get message stream",
 			  SCM_BOOL_F);
@@ -920,7 +914,7 @@ SCM_DEFINE_PUBLIC (scm_mu_message_get_port, "mu-message-get-port", 2, 1, 0,
       if (status)
 	mu_scm_error (FUNC_NAME, status, "Cannot get message body",
 		      SCM_BOOL_F);
-      status = mu_body_get_stream (body, &stream);
+      status = mu_body_get_streamref (body, &stream);
       if (status)
 	mu_scm_error (FUNC_NAME, status, "Cannot get message body stream",
 		      SCM_BOOL_F);

@@ -151,6 +151,8 @@ mu_port_close (SCM port)
 static scm_sizet
 mu_port_free (SCM port)
 {
+  struct mu_port *mp = MU_PORT (port);
+  mu_stream_unref (mp->stream);
   mu_port_close (port);
   return 0;
 }