Added to the repository

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
+
+   GNU Mailutils is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   GNU Mailutils 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GNU Mailutils; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA  */
+
+/* This file implements an MH draftfile stream: a read-only stream used
+   to transparently pass MH draftfiles to the mailers. The only difference
+   between the usual RFC822 and MH draft is that the latter allows to use
+   a string of dashes to separate the headers from the body. */
+
+#include <mh.h>
+#include <mailutils/stream.h>
+
+struct _mhdraft_stream {
+  stream_t stream;     /* Actual stream */
+  size_t mark_offset;  /* Offset of the header separator */
+  size_t mark_length;  /* Length of the header separator (not counting the
+			  newline) */
+};
+
+static int
+_mhdraft_read (stream_t stream, char *optr, size_t osize,
+	       off_t offset, size_t *nbytes)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+
+  if (offset < s->mark_offset)
+    {
+      if (offset + osize >= s->mark_offset)
+	osize = s->mark_offset - offset;
+    }
+  else
+    offset += s->mark_length;
+  return stream_read (s->stream, optr, osize, offset, nbytes);
+}
+  
+static int
+_mhdraft_readline (stream_t stream, char *optr, size_t osize,
+		   off_t offset, size_t *nbytes)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+    
+  if (offset < s->mark_offset)
+    {
+      if (offset + osize >= s->mark_offset)
+	{
+	  int rc;
+	  size_t n;
+	  size_t rdsize = s->mark_offset - offset;
+	  rc = stream_readline (s->stream, optr, rdsize, offset, &n);
+	  if (rc == 0)
+	    {
+	      if (nbytes)
+		*nbytes = n;
+	    }
+	  return rc;
+	}
+    }
+  else
+    offset += s->mark_length;
+
+  return stream_readline (s->stream, optr, osize, offset, nbytes);
+}
+  
+static int
+_mhdraft_size (stream_t stream, off_t *psize)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+  int rc = stream_size (s->stream, psize);
+  
+  if (rc == 0)
+    *psize -= s->mark_length;
+  return rc;
+}
+  
+static int
+_mhdraft_open (stream_t stream)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+  size_t offset, len;
+  char buffer[256];
+  int rc;
+
+  offset = 0;
+  while ((rc = stream_readline (s->stream, buffer, sizeof buffer,
+				offset, &len)) == 0
+	 && len > 0)
+    {
+      if (_mh_delim (buffer))
+	{
+	  s->mark_offset = offset;
+	  s->mark_length = len - 1; /* do not count the terminating newline */
+	  break;
+	}
+
+      offset += len;
+    }
+  return 0;
+}
+
+static int
+_mhdraft_close (stream_t stream)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+  return stream_close (s->stream);
+}
+
+static void
+_mhdraft_destroy (stream_t stream)
+{
+  struct _mhdraft_stream *s = stream_get_owner (stream);
+  if (s->stream)
+    stream_destroy (&s->stream, stream_get_owner (s->stream));
+  free (s);
+}
+    
+int
+mhdraft_stream_create (stream_t *stream, stream_t src, int flags)
+{
+  struct _mhdraft_stream *s;
+  int rc;
+
+  if (!flags)
+    flags = MU_STREAM_READ;
+  if (flags != MU_STREAM_READ)
+    return EINVAL;
+
+  s = calloc (1, sizeof (*s));
+  if (s == NULL)
+    return ENOMEM;
+
+  s->stream = src;
+  
+  rc = stream_create (stream, flags|MU_STREAM_NO_CHECK, s);
+  if (rc)
+    {
+      free (s);
+      return rc;
+    }
+  
+  stream_set_open (*stream, _mhdraft_open, s);
+  stream_set_close (*stream, _mhdraft_close, s);
+  stream_set_destroy (*stream, _mhdraft_destroy, s);
+  stream_set_readline (*stream, _mhdraft_readline, s);
+  stream_set_read (*stream, _mhdraft_read, s);
+  stream_set_size (*stream, _mhdraft_size, s);
+  return 0;  
+}
+
+