Add a framework for printing I/O transcripts; modify pop3d to use it.

* include/mailutils/stream.h (MU_STREAM_RDTHRU)
(MU_STREAM_WRTHRU,MU_IOCTL_SET_TRANSPORT): New flags.
(mu_xscript_stream_create, mu_iostream_create)
(mu_dbgstream_create): New prototypes.
* include/mailutils/sys/dbgstream.h: New header.
* include/mailutils/sys/iostream.h: New header.
* include/mailutils/sys/xscript-stream.h: New header.
* include/mailutils/sys/Makefile.am (sysinclude_HEADERS): Add
dbgstream.h, iostream.h and xscript-stream.h
* mailbox/dbgstream.c: New file.
* mailbox/iostream.c: New file.
* mailbox/xscript-stream.c: New file.
* mailbox/Makefile.am (libmailutils_la_SOURCES): Add dbgstream.c,
iostream.c and xscript-stream.c
* mailbox/filter_iconv.c (_icvt_ioctl): Simplify the declaration
of ptrans.
* mailbox/mapfile_stream.c (_mapfile_ioctl): Likewise.
* mailbox/memory_stream.c (_memory_ioctl): Likewise.
* mailbox/prog_stream.c (_prog_ioctl): Likewise.
* mailbox/tcp.c (_tcp_ioctl): Likewise.
* mailbox/fltstream.c (filter_ctl): Likewise.
(filter_read_through, filter_write_through): New methods.
(mu_filter_stream_create): Allow for use of MU_STREAM_RDTHRU
and MU_STREAM_WRTHRU to create two-way filters (writing
triggers filtering while reading is transparent or vice versa).
* pop3d/extra.c (istream, ostream): Remove globals.
(iostream): New variable.
(real_istream, real_ostream): New variables.
(pop3d_setio): Set transcript stream on top of the I/O one,
if required.
(pop3d_init_tls_server): Rewrite. Revert the meaning of the
return code to match the usual convention (0 - success).
(transcript): Removed.
(pop3d_outf): Remove calls to transcript.
* pop3d/pop3d.h (istream, ostream): Remove externs.
(iostream): New extern.
* pop3d/retr.c: Use iostream, instear of ostream.
* pop3d/top.c: Likewise.
* pop3d/stls.c: Update the call to pop3d_init_tls_server.

* mailbox/stream_vprintf.c (mu_stream_vprintf): Fix return
value to match the usual convention.

22 files changed, 876 insertions, 81 deletions

diff --git a/include/mailutils/stream.h b/include/mailutils/stream.h
index 1aee88493..1b74651c7 100644
--- a/include/mailutils/stream.h
+++ b/include/mailutils/stream.h
@@ -47,6 +47,9 @@ enum mu_buffer_type
 /* FIXME: This one affects only mailboxes */  
 #define MU_STREAM_QACCESS     0x00000200
 
+#define MU_STREAM_RDTHRU      0x00000400
+#define MU_STREAM_WRTHRU      0x00000800
+
 #define MU_STREAM_IRGRP       0x00001000
 #define MU_STREAM_IWGRP       0x00002000
 #define MU_STREAM_IROTH       0x00004000
@@ -59,6 +62,7 @@ enum mu_buffer_type
 #define MU_IOCTL_SET_SEEK_LIMITS 4
 #define MU_IOCTL_ABRIDGE_SEEK MU_IOCTL_SET_SEEK_LIMITS
 #define MU_IOCTL_GET_SEEK_LIMITS 5
+#define MU_IOCTL_SET_TRANSPORT   6
 
 void mu_stream_ref (mu_stream_t stream);
 void mu_stream_unref (mu_stream_t stream);
@@ -145,4 +149,12 @@ int mu_tcp_stream_create_with_source_host (mu_stream_t *stream,
 int mu_tcp_stream_create (mu_stream_t *stream, const char *host, int port,
 			  int flags);
 
+int mu_xscript_stream_create(mu_stream_t *pref, mu_stream_t transport,
+			     mu_stream_t logstr,
+			     const char *prefix[]);
+int mu_iostream_create (mu_stream_t *pref, mu_stream_t in, mu_stream_t out,
+			int flags);
+int mu_dbgstream_create(mu_stream_t *pref, mu_debug_t debug,
+			mu_log_level_t level, int flags);
+
 #endif
diff --git a/include/mailutils/sys/Makefile.am b/include/mailutils/sys/Makefile.am
index 34f995b59..ce37112b0 100644
--- a/include/mailutils/sys/Makefile.am
+++ b/include/mailutils/sys/Makefile.am
@@ -19,10 +19,12 @@
 
 sysincludedir=$(pkgincludedir)/sys
 sysinclude_HEADERS = \
+ dbgstream.h\
  file_stream.h\
  filter.h\
  header_stream.h\
  header.h\
+ iostream.h\
  mapfile_stream.h\
  memory_stream.h\
  message_stream.h\
@@ -36,4 +38,5 @@ sysinclude_HEADERS = \
  stream.h\
  tls-stream.h\
  pop3.h\
- nntp.h
+ nntp.h\
+ xscript-stream.h
diff --git a/include/mailutils/sys/dbgstream.h b/include/mailutils/sys/dbgstream.h
new file mode 100644
index 000000000..6934372b6
--- /dev/null
+++ b/include/mailutils/sys/dbgstream.h
@@ -0,0 +1,31 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _MAILUTILS_SYS_DBGSTREAM_H
+# define _MAILUTILS_SYS_DBGSTREAM_H
+
+# include <mailutils/types.h>
+# include <mailutils/stream.h>
+# include <mailutils/sys/stream.h>
+
+struct _mu_dbgstream
+{
+  struct _mu_stream stream;
+  mu_debug_t debug;
+  mu_log_level_t level;
+};
+
+#endif
diff --git a/include/mailutils/sys/iostream.h b/include/mailutils/sys/iostream.h
new file mode 100644
index 000000000..d8922f6a5
--- /dev/null
+++ b/include/mailutils/sys/iostream.h
@@ -0,0 +1,34 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _MAILUTILS_SYS_IOSTREAM_H
+# define _MAILUTILS_SYS_IOSTREAM_H
+
+# include <mailutils/types.h>
+# include <mailutils/stream.h>
+# include <mailutils/sys/stream.h>
+
+# define _MU_STREAM_INPUT 0
+# define _MU_STREAM_OUTPUT 1
+
+struct _mu_iostream
+{
+  struct _mu_stream stream;
+  mu_stream_t transport[2];
+  int last_err_str;
+};
+
+#endif
diff --git a/include/mailutils/sys/xscript-stream.h b/include/mailutils/sys/xscript-stream.h
new file mode 100644
index 000000000..c6b45387a
--- /dev/null
+++ b/include/mailutils/sys/xscript-stream.h
@@ -0,0 +1,33 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _MAILUTILS_SYS_XSCRIPT_STREAM_H
+# define _MAILUTILS_SYS_XSCRIPT_STREAM_H
+
+# include <mailutils/types.h>
+# include <mailutils/stream.h>
+# include <mailutils/sys/stream.h>
+
+struct _mu_xscript_stream
+{
+  struct _mu_stream stream;
+  mu_stream_t transport;
+  mu_stream_t logstr;
+  int flags;
+  char *prefix[2];
+};
+
+#endif
diff --git a/mailbox/Makefile.am b/mailbox/Makefile.am
index 0d0493033..1fd892dfa 100644
--- a/mailbox/Makefile.am
+++ b/mailbox/Makefile.am
@@ -69,6 +69,7 @@ libmailutils_la_SOURCES = \
  daemon.c\
  date.c\
  dbgstderr.c\
+ dbgstream.c\
  dbgsyslog.c\
  debug.c\
  diag.c\
@@ -84,6 +85,7 @@ libmailutils_la_SOURCES = \
  gocs.c\
  hdritr.c\
  header.c\
+ iostream.c\
  iterator.c\
  ipsrv.c\
  kwd.c\
@@ -150,7 +152,8 @@ libmailutils_la_SOURCES = \
  vartab.c\
  vasnprintf.c\
  version.c\
- wicket.c
+ wicket.c\
+ xscript-stream.c
  
 BUILT_SOURCES = parsedate.c muerrno.c cfg_parser.c cfg_parser.h cfg_lexer.c
 MOSTLYCLEANFILES=
diff --git a/mailbox/dbgstream.c b/mailbox/dbgstream.c
new file mode 100644
index 000000000..19c137d3f
--- /dev/null
+++ b/mailbox/dbgstream.c
@@ -0,0 +1,86 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 
+   2005, 2006, 2007, 2008, 2009, 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <mailutils/types.h>
+#include <mailutils/alloc.h>
+#include <mailutils/errno.h>
+
+#include <mailutils/nls.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/stream.h>
+#include <mailutils/sys/dbgstream.h>
+#include <mailutils/debug.h>
+
+static int
+_dbg_write (struct _mu_stream *str, const char *buf, size_t size,
+	    size_t *pnwrite)
+{
+  struct _mu_dbgstream *sp = (struct _mu_dbgstream *)str;
+  if (pnwrite)
+    *pnwrite = size;
+  while (size > 0 && (buf[size-1] == '\n' || buf[size-1] == '\r'))
+    size--;
+  if (size)
+    mu_debug_printf (sp->debug, sp->level, "%.*s\n", size, buf);
+  return 0;
+}
+
+static int
+_dbg_flush (struct _mu_stream *str)
+{
+  struct _mu_dbgstream *sp = (struct _mu_dbgstream *)str;
+  mu_debug_printf (sp->debug, sp->level, "\n");
+  return 0;
+}
+
+static void
+_dbg_done (struct _mu_stream *str)
+{
+  struct _mu_dbgstream *sp = (struct _mu_dbgstream *)str;
+  if (!(str->flags & MU_STREAM_NO_CLOSE))
+    mu_debug_destroy (&sp->debug, NULL);
+}
+
+int
+mu_dbgstream_create(mu_stream_t *pref, mu_debug_t debug, mu_log_level_t level,
+		    int flags)
+{
+  struct _mu_dbgstream *sp;
+
+  sp = (struct _mu_dbgstream *)
+    _mu_stream_create (sizeof (*sp), MU_STREAM_WRITE |
+		       (flags & MU_STREAM_NO_CLOSE));
+  if (!sp)
+    return ENOMEM;
+  sp->stream.write = _dbg_write;
+  sp->stream.flush = _dbg_flush;
+  sp->stream.done = _dbg_done;
+  
+  sp->debug = debug;
+  sp->level = level;
+  mu_stream_set_buffer ((mu_stream_t) sp, mu_buffer_line, 1024);
+  *pref = (mu_stream_t) sp;
+  return 0;
+}
+  
diff --git a/mailbox/file_stream.c b/mailbox/file_stream.c
index c97075f5f..7dc8c90fa 100644
--- a/mailbox/file_stream.c
+++ b/mailbox/file_stream.c
@@ -192,7 +192,7 @@ static int
 fd_ioctl (struct _mu_stream *str, int code, void *ptr)
 {
   struct _mu_file_stream *fstr = (struct _mu_file_stream *) str;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
   
   switch (code)
     {
@@ -200,8 +200,8 @@ fd_ioctl (struct _mu_stream *str, int code, void *ptr)
       if (!ptr)
 	return EINVAL;
       ptrans = ptr;
-      (*ptrans)[0] = (mu_transport_t) fstr->fd;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) fstr->fd;
+      ptrans[1] = NULL;
       break;
 
     default:
diff --git a/mailbox/filter_iconv.c b/mailbox/filter_iconv.c
index 6674ba4ea..c948df407 100644
--- a/mailbox/filter_iconv.c
+++ b/mailbox/filter_iconv.c
@@ -390,7 +390,7 @@ static int
 _icvt_ioctl (mu_stream_t stream, int code, void *ptr)
 {
   struct icvt_stream *s = (struct icvt_stream *)stream;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
   
   switch (code)
     {
@@ -398,8 +398,8 @@ _icvt_ioctl (mu_stream_t stream, int code, void *ptr)
       if (!ptr)
 	return EINVAL;
       ptrans = ptr;
-      (*ptrans)[0] = (mu_transport_t) s->transport;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) s->transport;
+      ptrans[1] = NULL;
       break;
 
     default:
diff --git a/mailbox/fltstream.c b/mailbox/fltstream.c
index 8f6260aa2..c75913489 100644
--- a/mailbox/fltstream.c
+++ b/mailbox/fltstream.c
@@ -335,7 +335,7 @@ static int
 filter_ctl (struct _mu_stream *stream, int op, void *ptr)
 {
   struct _mu_filter_stream *fs = (struct _mu_filter_stream *)stream;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
 
   switch (op)
     {
@@ -343,8 +343,8 @@ filter_ctl (struct _mu_stream *stream, int op, void *ptr)
       if (!ptr)
 	return EINVAL;
       ptrans = ptr;
-      (*ptrans)[0] = (mu_transport_t) fs->transport;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) fs->transport;
+      ptrans[1] = NULL;
       break;
 
     default:
@@ -390,6 +390,26 @@ filter_close (mu_stream_t stream)
   return mu_stream_close (fs->transport);
 }
 
+
+static int
+filter_read_through (struct _mu_stream *stream,
+		     char *buf, size_t bufsize,
+		     size_t *pnread)
+{
+  struct _mu_filter_stream *fs = (struct _mu_filter_stream *)stream;
+  return mu_stream_read (fs->transport, buf, bufsize, pnread);
+}
+
+static int
+filter_write_through (struct _mu_stream *stream,
+		      const char *buf, size_t bufsize,
+		      size_t *pnwrite)
+{
+  struct _mu_filter_stream *fs = (struct _mu_filter_stream *)stream;
+  return mu_stream_write (fs->transport, buf, bufsize, pnwrite);
+}
+
+
 int
 mu_filter_stream_create (mu_stream_t *pflt,
 			 mu_stream_t str,
@@ -402,7 +422,14 @@ mu_filter_stream_create (mu_stream_t *pflt,
 
   if ((flags & MU_STREAM_RDWR) == MU_STREAM_RDWR
       || !(flags & MU_STREAM_RDWR)
-      || (flags & (MU_STREAM_WRITE|MU_STREAM_SEEK)) == (MU_STREAM_WRITE|MU_STREAM_SEEK))
+      || (flags & (MU_STREAM_WRITE|MU_STREAM_SEEK)) ==
+          (MU_STREAM_WRITE|MU_STREAM_SEEK)
+      || (flags & (MU_STREAM_RDTHRU|MU_STREAM_WRTHRU)) ==
+	  (MU_STREAM_RDTHRU|MU_STREAM_WRTHRU)
+      || (flags & (MU_STREAM_READ|MU_STREAM_RDTHRU)) ==
+	  (MU_STREAM_READ|MU_STREAM_RDTHRU)
+      || (flags & (MU_STREAM_WRITE|MU_STREAM_WRTHRU)) ==
+          (MU_STREAM_WRITE|MU_STREAM_WRTHRU))
     return EINVAL;
  
   fs = (struct _mu_filter_stream *) _mu_stream_create (sizeof (*fs), flags);
@@ -413,11 +440,21 @@ mu_filter_stream_create (mu_stream_t *pflt,
     {
       fs->stream.read = filter_read;
       fs->stream.flush = filter_rd_flush;
+      if (flags & MU_STREAM_WRTHRU)
+	{
+	  flags |= MU_STREAM_WRITE;
+	  fs->stream.write = filter_write_through;
+	}
     }
   else
     {
       fs->stream.write = filter_write;
       fs->stream.flush = filter_wr_flush;
+      if (flags & MU_STREAM_RDTHRU)
+	{
+	  flags |= MU_STREAM_READ;
+	  fs->stream.read = filter_read_through;
+	}
     }
   fs->stream.done = filter_done;
   fs->stream.close = filter_close;
diff --git a/mailbox/iostream.c b/mailbox/iostream.c
new file mode 100644
index 000000000..4b76d3ab4
--- /dev/null
+++ b/mailbox/iostream.c
@@ -0,0 +1,249 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <mailutils/types.h>
+#include <mailutils/alloc.h>
+#include <mailutils/errno.h>
+
+#include <mailutils/nls.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/stream.h>
+#include <mailutils/sys/iostream.h>
+
+static int
+_iostream_read (struct _mu_stream *str, char *buf, size_t bufsize,
+		size_t *pnread)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = mu_stream_read (sp->transport[_MU_STREAM_INPUT], buf, bufsize,
+			   pnread);
+  if (rc)
+    sp->last_err_str = _MU_STREAM_INPUT;
+  return rc;
+}
+
+static int
+_iostream_readdelim (struct _mu_stream *str, char *buf, size_t bufsize,
+		    int delim, size_t *pnread)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = mu_stream_readdelim (sp->transport[_MU_STREAM_INPUT], buf,
+				bufsize, delim, pnread);
+  if (rc)
+    sp->last_err_str = _MU_STREAM_INPUT;
+  return rc;
+}
+
+static int
+_iostream_write (struct _mu_stream *str, const char *buf, size_t bufsize,
+		  size_t *pnwrite)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = mu_stream_write (sp->transport[_MU_STREAM_OUTPUT], buf, bufsize,
+			    pnwrite);
+  if (rc)
+    sp->last_err_str = _MU_STREAM_OUTPUT;
+  return rc;
+}
+
+static int
+_iostream_flush (struct _mu_stream *str)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = mu_stream_flush (sp->transport[_MU_STREAM_INPUT]);
+  if (rc)
+    {
+      sp->last_err_str = _MU_STREAM_INPUT;
+      return rc;
+    }
+  if (sp->transport[_MU_STREAM_INPUT] != sp->transport[_MU_STREAM_OUTPUT])
+    {
+      rc = mu_stream_flush (sp->transport[_MU_STREAM_OUTPUT]);
+      if (rc)
+	sp->last_err_str = _MU_STREAM_OUTPUT;
+    }
+  return rc;
+}
+
+static int
+_iostream_open (struct _mu_stream *str)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc;
+  rc = mu_stream_open (sp->transport[_MU_STREAM_INPUT]);
+  if (rc)
+    {
+      sp->last_err_str = _MU_STREAM_INPUT;
+      return rc;
+    }
+  if (sp->transport[_MU_STREAM_INPUT] != sp->transport[_MU_STREAM_OUTPUT])
+    {
+      rc = mu_stream_open (sp->transport[_MU_STREAM_OUTPUT]);
+      if (rc)
+	{
+	  sp->last_err_str = _MU_STREAM_OUTPUT;
+	  mu_stream_close (sp->transport[_MU_STREAM_INPUT]);
+	}
+    }
+  return rc;
+}
+
+static int
+_iostream_close (struct _mu_stream *str)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  if (sp->stream.flags & MU_STREAM_NO_CLOSE)
+    return 0;
+  mu_stream_close (sp->transport[_MU_STREAM_INPUT]);
+  if (sp->transport[_MU_STREAM_INPUT] != sp->transport[_MU_STREAM_OUTPUT])
+    mu_stream_close (sp->transport[_MU_STREAM_OUTPUT]);
+  return 0;
+}
+
+static void
+_iostream_done (struct _mu_stream *str)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  mu_stream_unref (sp->transport[_MU_STREAM_INPUT]);
+  if (sp->transport[_MU_STREAM_INPUT] != sp->transport[_MU_STREAM_OUTPUT])
+    mu_stream_unref (sp->transport[_MU_STREAM_OUTPUT]);
+}
+
+static int
+_iostream_ctl (struct _mu_stream *str, int op, void *arg)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  mu_transport_t *ptrans;
+
+  switch (op)
+    {
+    case MU_IOCTL_GET_TRANSPORT:
+      if (!arg)
+	return EINVAL;
+      ptrans = arg;
+      ptrans[0] = (mu_transport_t) sp->transport[_MU_STREAM_INPUT];
+      ptrans[1] = (mu_transport_t) sp->transport[_MU_STREAM_OUTPUT];
+      break;
+
+    case MU_IOCTL_SET_TRANSPORT:
+      if (!arg)
+	return EINVAL;
+      ptrans = arg;
+      sp->transport[_MU_STREAM_INPUT] = (mu_stream_t) ptrans[0];
+      sp->transport[_MU_STREAM_OUTPUT] = (mu_stream_t) ptrans[1];
+      break;
+      
+    default:
+      return EINVAL;
+    }
+  return 0;
+}
+
+static int
+_iostream_wait (struct _mu_stream *str, int *pflags, struct timeval *tvp)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = EINVAL;
+  
+  if (*pflags == MU_STREAM_READY_RD)
+    {
+      rc = mu_stream_wait (sp->transport[_MU_STREAM_INPUT], pflags, tvp);
+      if (rc)
+	sp->last_err_str = _MU_STREAM_INPUT;
+    }
+  else if (*pflags == MU_STREAM_READY_WR)
+    {
+      rc = mu_stream_wait (sp->transport[_MU_STREAM_OUTPUT], pflags, tvp);
+      if (rc)
+	sp->last_err_str = _MU_STREAM_OUTPUT;
+    }
+  return rc;
+}
+
+static int
+_iostream_shutdown (struct _mu_stream *str, int how)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  int rc = EINVAL;
+  switch (how)
+    {
+    case MU_STREAM_READ:
+      rc = mu_stream_shutdown (sp->transport[_MU_STREAM_INPUT], how);
+      if (rc)
+	sp->last_err_str = _MU_STREAM_INPUT;
+      break;
+      
+    case MU_STREAM_WRITE:
+      rc = mu_stream_shutdown (sp->transport[_MU_STREAM_OUTPUT], how);
+      if (rc)
+	sp->last_err_str = _MU_STREAM_OUTPUT;
+    }
+  return rc;
+}
+
+static const char *
+_iostream_error_string (struct _mu_stream *str, int rc)
+{
+  struct _mu_iostream *sp = (struct _mu_iostream *)str;
+  mu_stream_t transport = sp->transport[sp->last_err_str];
+  if (transport)
+    return mu_stream_strerror (transport, rc);
+  return mu_strerror (rc);
+}
+
+int
+mu_iostream_create (mu_stream_t *pref, mu_stream_t in, mu_stream_t out,
+		    int flags)
+{
+  struct _mu_iostream *sp;
+
+  sp = (struct _mu_iostream *)
+    _mu_stream_create (sizeof (*sp),
+		       MU_STREAM_READ | MU_STREAM_WRITE |
+		       (flags & MU_STREAM_NO_CLOSE));
+  if (!sp)
+    return ENOMEM;
+
+  sp->stream.read = _iostream_read; 
+  sp->stream.readdelim = _iostream_readdelim; 
+  sp->stream.write = _iostream_write;
+  sp->stream.flush = _iostream_flush;
+  sp->stream.open = _iostream_open; 
+  sp->stream.close = _iostream_close;
+  sp->stream.done = _iostream_done; 
+  sp->stream.ctl = _iostream_ctl;
+  sp->stream.wait = _iostream_wait;
+  sp->stream.shutdown = _iostream_shutdown;
+  sp->stream.error_string = _iostream_error_string;
+
+  mu_stream_ref (in);
+  sp->transport[_MU_STREAM_INPUT] = in;
+  mu_stream_ref (out);
+  sp->transport[_MU_STREAM_OUTPUT] = out;
+
+  mu_stream_set_buffer ((mu_stream_t) sp, mu_buffer_line, 1024);
+  *pref = (mu_stream_t) sp;
+  return 0;
+}
+
+
diff --git a/mailbox/mapfile_stream.c b/mailbox/mapfile_stream.c
index 89b3e4776..aeb85e5fe 100644
--- a/mailbox/mapfile_stream.c
+++ b/mailbox/mapfile_stream.c
@@ -209,13 +209,13 @@ static int
 _mapfile_ioctl (struct _mu_stream *str, int code, void *ptr)
 {
   struct _mu_mapfile_stream *mfs = (struct _mu_mapfile_stream *) str;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t ptrans[2];
   
   switch (code)
     {
     case MU_IOCTL_GET_TRANSPORT:
-      (*ptrans)[0] = (mu_transport_t) mfs->fd;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) mfs->fd;
+      ptrans[1] = NULL;
       break;
 
     default:
diff --git a/mailbox/memory_stream.c b/mailbox/memory_stream.c
index ecb091fa9..19d459083 100644
--- a/mailbox/memory_stream.c
+++ b/mailbox/memory_stream.c
@@ -147,7 +147,7 @@ static int
 _memory_ioctl (struct _mu_stream *stream, int code, void *ptr)
 {
   struct _mu_memory_stream *mfs = (struct _mu_memory_stream *) stream;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
   
   switch (code)
     {
@@ -155,8 +155,8 @@ _memory_ioctl (struct _mu_stream *stream, int code, void *ptr)
       if (!ptr)
 	return EINVAL;
       ptrans = ptr;
-      (*ptrans)[0] = (mu_transport_t) mfs->ptr;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) mfs->ptr;
+      ptrans[1] = NULL;
       break;
 
     default:
diff --git a/mailbox/prog_stream.c b/mailbox/prog_stream.c
index 7c6594048..4c0bb8eaf 100644
--- a/mailbox/prog_stream.c
+++ b/mailbox/prog_stream.c
@@ -367,7 +367,7 @@ _prog_ioctl (struct _mu_stream *str, int code, void *ptr)
 {
   struct _mu_prog_stream *fstr = (struct _mu_prog_stream *) str;
   mu_transport_t t[2];
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
   
   switch (code)
     {
@@ -375,9 +375,9 @@ _prog_ioctl (struct _mu_stream *str, int code, void *ptr)
       if (!ptr)
       	return EINVAL;
       mu_stream_ioctl (fstr->in, MU_IOCTL_GET_TRANSPORT, t);
-      (*ptrans)[0] = t[0];
+      ptrans[0] = t[0];
       mu_stream_ioctl (fstr->out, MU_IOCTL_GET_TRANSPORT, t);
-      (*ptrans)[1] = t[1];
+      ptrans[1] = t[1];
       break;
 
     case MU_IOCTL_GET_STATUS:
diff --git a/mailbox/stream_vprintf.c b/mailbox/stream_vprintf.c
index db0bff38b..5bd9c09e0 100644
--- a/mailbox/stream_vprintf.c
+++ b/mailbox/stream_vprintf.c
@@ -37,6 +37,6 @@ mu_stream_vprintf (mu_stream_t str, const char *fmt, va_list ap)
   n = strlen (buf);
   rc = mu_stream_write (str, buf, n, NULL);
   free (buf);
-  return rc == 0 ? n : -1;
+  return rc;
 }
 
diff --git a/mailbox/tcp.c b/mailbox/tcp.c
index a03eedb7c..081072825 100644
--- a/mailbox/tcp.c
+++ b/mailbox/tcp.c
@@ -196,7 +196,7 @@ static int
 _tcp_ioctl (mu_stream_t stream, int code, void *ptr)
 {
   struct _tcp_instance *tcp = (struct _tcp_instance *)stream;
-  mu_transport_t (*ptrans)[2];
+  mu_transport_t *ptrans;
 
   switch (code)
     {
@@ -204,8 +204,8 @@ _tcp_ioctl (mu_stream_t stream, int code, void *ptr)
       if (!ptr)
 	return EINVAL;
       ptrans = ptr;
-      (*ptrans)[0] = (mu_transport_t) tcp->fd;
-      (*ptrans)[1] = NULL;
+      ptrans[0] = (mu_transport_t) tcp->fd;
+      ptrans[1] = NULL;
       break;
 
     default:
diff --git a/mailbox/xscript-stream.c b/mailbox/xscript-stream.c
new file mode 100644
index 000000000..c3a5c4081
--- /dev/null
+++ b/mailbox/xscript-stream.c
@@ -0,0 +1,300 @@
+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002, 2004, 
+   2005, 2006, 2007, 2008, 2009, 2010 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, 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 GNU Mailutils.  If not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <mailutils/types.h>
+#include <mailutils/alloc.h>
+#include <mailutils/errno.h>
+
+#include <mailutils/nls.h>
+#include <mailutils/stream.h>
+#include <mailutils/sys/stream.h>
+#include <mailutils/sys/xscript-stream.h>
+
+/* A "transcript stream" transparently writes data to and reads data from
+   an underlying transport stream, writing each lineful of data to a "log
+   stream". Writes to log stream are prefixed with a string indicating
+   direction of the data (read/write). Default prefixes are those used in
+   RFCs -- "S: ", for data written ("Server"), and "C: ", for data read
+   ("Client"). */
+
+#define TRANS_READ 0x1
+#define TRANS_WRITE 0x2
+#define FLAG_TO_PFX(c) ((c) - 1)
+
+static void
+print_transcript (struct _mu_xscript_stream *str, int flag,
+		  const char *buf, size_t size)
+{
+    while (size)
+      {
+	const char *p;
+	size_t len;
+