Implement a filter for quoting ^From. Use it for appending to UNIX mailboxes.

* libmailutils/fromflt.c: New file.
* libmailutils/Makefile.am (libmailutils_la_SOURCES): Add fromflt.c
* libmailutils/tests/testsuite.at: Include fromflt.at.
* include/mailutils/filter.h (mu_from_filter): New filter type.
* libmailutils/filter.c (mu_filter_get_list): Register mu_from_filter.

* libmailutils/fromflt.at: New file.
* libmailutils/tests/Makefile.am (TESTSUITE_AT): Add fromflt.at.
* libmailutils/tests/base64d.at: Mention `filter' in the keywords.
* libmailutils/tests/base64e.at: Likewise.
* libmailutils/tests/fltst.c (main): Fix argc check.

* libproto/mbox/mbox.c (append_message_to_stream): Use "FROM" filter.

@@ -103,7 +103,8 @@ extern mu_filter_record_t mu_bit8_filter;
 extern mu_filter_record_t mu_bit7_filter;
 extern mu_filter_record_t mu_rfc_2047_Q_filter;
 extern mu_filter_record_t mu_rfc_2047_B_filter;
-  
+extern mu_filter_record_t mu_from_filter;
+
 enum mu_iconv_fallback_mode
   {
     mu_fallback_none,

@@ -83,6 +83,7 @@ libmailutils_la_SOURCES = \
  fltstream.c\
  folder.c\
  freeitem.c\
+ fromflt.c\
  gdebug.c\
  getpass.c\
  gocs.c\

@@ -78,6 +78,7 @@ mu_filter_get_list (mu_list_t *plist)
       mu_list_append (filter_list, mu_dot_filter);
       mu_list_append (filter_list, mu_rfc_2047_Q_filter);
       mu_list_append (filter_list, mu_rfc_2047_B_filter);
+      mu_list_append (filter_list, mu_from_filter);
       /* FIXME: add the default encodings?  */
     }
   *plist = filter_list;

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2003, 2007, 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 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, write to the
+   Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301 USA */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <mailutils/errno.h>
+#include <mailutils/filter.h>
+#include <mailutils/stream.h>
+
+enum from_decode_state
+  {
+    from_decode_init,
+    from_decode_nl,
+    from_decode_char
+  };
+
+#define GT_FROM_MARK_STR ">From "
+#define GT_FROM_MARK_LEN (sizeof (GT_FROM_MARK_STR) - 1)
+
+/* Move min(isize,osize) bytes from iptr to optr, replacing each '>From '
+   at the beginning of line with 'From '. */
+static enum mu_filter_result
+_from_decoder (void *xd,
+	       enum mu_filter_command cmd,
+	       struct mu_filter_io *iobuf)
+{
+  int *pstate = xd;
+  const unsigned char *iptr;
+  size_t isize;
+  char *optr;
+  size_t osize;
+  enum from_decode_state state;
+  size_t i, j;
+
+  switch (cmd)
+    {
+    case mu_filter_init:
+      *pstate = from_decode_init;
+      return mu_filter_ok;
+      
+    case mu_filter_done:
+      return mu_filter_ok;
+      
+    default:
+      state = *pstate;
+      break;
+    }
+  
+  iptr = (const unsigned char *) iobuf->input;
+  isize = iobuf->isize;
+  optr = iobuf->output;
+  osize = iobuf->osize;
+
+  for (i = j = 0; i < isize && j < osize; i++)
+    {
+      unsigned char c = *iptr++;
+      
+      if (c == '\n')
+	state = from_decode_nl;
+      else if (state == from_decode_init || state == from_decode_nl)
+	{
+	  size_t len = isize - i;
+
+	  if (len < GT_FROM_MARK_LEN)
+	    {
+	      if (memcmp (iptr - 1, GT_FROM_MARK_STR, len) == 0)
+		{
+		  if (i == 0)
+		    {
+		      iobuf->isize = GT_FROM_MARK_LEN - len;
+		      return mu_filter_moreinput;
+		    }
+		  break;
+		}
+	      else
+		state = from_decode_char;
+	    }
+	  else if (memcmp (iptr - 1, GT_FROM_MARK_STR, GT_FROM_MARK_LEN) == 0)
+	    {
+	      /* Skip > */
+	      state = from_decode_char;
+	      continue;
+	    }
+	}	  
+      optr[j++] = c;
+    }
+
+  *pstate = state;
+  iobuf->isize = i;
+  iobuf->osize = j;
+  return mu_filter_ok;
+}
+
+#define FROM_MARK_STR "From "
+#define FROM_MARK_LEN (sizeof (FROM_MARK_STR) - 1)
+
+enum from_encode_state
+  {
+    from_encode_init,
+    from_encode_nl,
+    from_encode_char,
+    from_encode_gt,
+    from_encode_f,
+    from_encode_r,
+    from_encode_o,
+    from_encode_m,
+    from_encode_sp
+  };
+
+static int length_to_state_tab[] = {
+  from_encode_gt,
+  from_encode_f,
+  from_encode_r,
+  from_encode_o,
+  from_encode_m,
+  from_encode_sp
+};
+
+static int state_to_length_tab[] = {
+  0, 0, 0,
+  GT_FROM_MARK_LEN,
+  GT_FROM_MARK_LEN-1,
+  GT_FROM_MARK_LEN-2,
+  GT_FROM_MARK_LEN-3,
+  GT_FROM_MARK_LEN-4,
+  GT_FROM_MARK_LEN-5
+};      
+
+/* Move min(isize,osize) bytes from iptr to optr, replacing each 'From '
+   at the beginning of line with '>From '. */
+
+static enum mu_filter_result
+_from_encoder (void *xd,
+	       enum mu_filter_command cmd,
+	       struct mu_filter_io *iobuf)
+{
+  int *pstate = xd;
+  const unsigned char *iptr;
+  size_t isize;
+  char *optr;
+  size_t osize;
+  enum from_encode_state state;
+  size_t i, j;
+  
+  switch (cmd)
+    {
+    case mu_filter_init:
+      *pstate = from_encode_init;
+      return mu_filter_ok;
+      
+    case mu_filter_done:
+      return mu_filter_ok;
+      
+    default:
+      state = *pstate;
+      switch (state)
+	{
+	case from_encode_init:
+	case from_encode_nl:
+	case from_encode_char:
+	  break;
+
+	default:
+	  osize = state_to_length_tab[state];
+	  if (iobuf->osize < osize)
+	    {
+	      iobuf->osize = osize;
+	      return mu_filter_moreoutput;
+	    }
+	  memcpy (iobuf->output, GT_FROM_MARK_STR + GT_FROM_MARK_LEN - osize,
+		  osize);
+	  iobuf->osize = osize;
+	  iobuf->isize = osize;
+	  *pstate = from_encode_init;
+	  return mu_filter_ok;
+	}
+      break;
+    }
+  
+  iptr = (const unsigned char *) iobuf->input;
+  isize = iobuf->isize;
+  optr = iobuf->output;
+  osize = iobuf->osize;
+
+  for (i = j = 0; i < isize && j < osize; i++)
+    {
+      unsigned char c = *iptr++;
+      
+      if (c == '\n')
+	state = from_encode_nl;
+      else if (state == from_encode_init || state == from_encode_nl)
+	{
+	  size_t len = isize - i;
+
+	  if (len < FROM_MARK_LEN)
+	    {
+	      if (memcmp (iptr - 1, FROM_MARK_STR, len) == 0)
+		{
+		  if (i == 0)
+		    {
+		      iobuf->isize = FROM_MARK_LEN;
+		      return mu_filter_moreinput;
+		    }
+		  break;
+		}
+	      else
+		state = from_encode_char;
+	    }
+	  else if (memcmp (iptr - 1, FROM_MARK_STR, FROM_MARK_LEN) == 0)
+	    {
+	      size_t rest = osize - j;
+	      
+	      if (rest > GT_FROM_MARK_LEN)
+		rest = GT_FROM_MARK_LEN;
+	      else if (rest < 2)
+		{
+		  if (i == 0)
+		    {
+		      iobuf->osize = GT_FROM_MARK_LEN;
+		      return mu_filter_moreoutput;
+		    }
+		  break;
+		}
+	      
+	      memcpy (optr + j, GT_FROM_MARK_STR, rest);
+	      i += rest - 2;
+	      iptr += rest - 2;
+	      j += rest;
+	      if (rest < GT_FROM_MARK_LEN)
+		state = length_to_state_tab[rest];
+	      else
+		state = from_encode_char;
+	      continue;
+	    }
+	  else
+	    state = from_encode_char;
+	}
+      optr[j++] = c;
+    }
+  *pstate = state;
+  iobuf->isize = i;
+  iobuf->osize = j;
+  return mu_filter_ok;
+}
+
+static int
+_from_alloc_state (void **pret, int mode, void *data MU_ARG_UNUSED)
+{
+  *pret = malloc (sizeof (int));
+  if (!*pret)
+    return ENOMEM;
+  return 0;
+}
+
+static struct _mu_filter_record _from_filter = {
+  "FROM",
+  0,
+  _from_alloc_state,
+  _from_encoder,
+  _from_decoder
+};
+
+mu_filter_record_t mu_from_filter = &_from_filter;
+

@@ -64,6 +64,7 @@ TESTSUITE_AT = \
  base64e.at\
  decode2047.at\
  encode2047.at\
+ fromflt.at\
  list.at\
  mailcap.at\
  testsuite.at\

@@ -16,7 +16,7 @@
 # This file is part of Mailfromd testsuite. 
 
 AT_SETUP([base64 decoding (read)])
-AT_KEYWORDS([base64 base64d base64dr decode])
+AT_KEYWORDS([base64 base64d base64dr decode filter])
 
 AT_CHECK([
 cp $abs_top_srcdir/libmailutils/tests/Encode expout
@@ -28,7 +28,7 @@ AT_CLEANUP
 
 
 AT_SETUP([base64 decoding (write)])
-AT_KEYWORDS([base64 base64d base64dw decode])
+AT_KEYWORDS([base64 base64d base64dw decode filter])
 
 AT_CHECK([
 cp $abs_top_srcdir/libmailutils/tests/Encode expout

@@ -16,7 +16,7 @@
 # This file is part of Mailfromd testsuite. 
 
 AT_SETUP([base64 encoding (read)])
-AT_KEYWORDS([base64 base64e base64er encode])
+AT_KEYWORDS([base64 base64e base64er encode filter])
 
 AT_CHECK([
 cp $abs_top_srcdir/libmailutils/tests/Decode expout
@@ -28,7 +28,7 @@ AT_CLEANUP
 
 
 AT_SETUP([base64 encoding (write)])
-AT_KEYWORDS([base64 base64e base64ew encode])
+AT_KEYWORDS([base64 base64e base64ew encode filter])
 
 AT_CHECK([
 cp $abs_top_srcdir/libmailutils/tests/Decode expout

@@ -114,7 +114,7 @@ main (int argc, char * argv [])
   
   if (argc == 1)
     usage (NULL);
-  if (argc < 3)
+  if (argc < 4)
     usage ("not enough arguments");
   
   fltname = argv[1];

+# This file is part of GNU Mailutils. -*- Autotest -*-
+# Copyright (C) 2007, 2008, 2009, 2010 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 3, or (at
+# your option) any later version.
+#
+# This program 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, see <http://www.gnu.org/licenses/>.
+# This file is part of Mailfromd testsuite. 
+
+# -------------------------------------------
+# Data for 'From' filter tests.
+# -------------------------------------------
+
+m4_define([from_plain_text],[From this time on
+from that source
+ From stdin
+and
+From them
+])
+
+m4_define([from_encoded_text],[>From this time on
+from that source
+ From stdin
+and
+>From them
+])
+
+# -------------------------------------------
+# Test 'From' encoding
+# -------------------------------------------
+
+# Test read mode
+
+AT_SETUP([from filter encoding (read)])
+AT_KEYWORDS([from frome fromer encode])
+
+AT_CHECK([
+AT_DATA([input],from_plain_text)
+fltst from encode read < input
+],
+[0],
+[from_encoded_text])
+
+AT_CLEANUP
+
+# The same, in write mode
+
+AT_SETUP([from filter encoding (write)])
+AT_KEYWORDS([from frome fromew encode])
+
+AT_CHECK([
+AT_DATA([input],from_plain_text)
+fltst from encode write < input
+],
+[0],
+[from_encoded_text])
+
+AT_CLEANUP
+
+# -------------------------------------------
+# Test '>From' decoding
+# -------------------------------------------
+
+AT_SETUP([from filter decoding (read)])
+AT_KEYWORDS([from fromd fromdr decode])
+
+AT_CHECK([
+AT_DATA([input],from_encoded_text)
+fltst from decode read < input
+],
+[0],
+[from_plain_text])
+
+AT_CLEANUP
+
+# The same, in write mode
+
+AT_SETUP([from filter decoding (write)])
+AT_KEYWORDS([from fromd fromdw decode])
+
+AT_CHECK([
+AT_DATA([input],from_encoded_text)
+fltst from decode write < input
+],
+[0],
+[from_plain_text])
+
+AT_CLEANUP

@@ -63,4 +63,5 @@ m4_include([base64e.at])
 m4_include([base64d.at])
 m4_include([decode2047.at])
 m4_include([encode2047.at])
+m4_include([fromflt.at])
 

@@ -28,6 +28,7 @@
 #include <mbox0.h>
 #include <mailutils/cstr.h>
 #include <mailutils/io.h>
+#include <mailutils/filter.h>
 
 #define ATTRIBUTE_IS_DELETED(flag)        (flag & MU_ATTRIBUTE_DELETED)
 #define ATTRIBUTE_IS_EQUAL(flag1, flag2)  (flag1 == flag2)
@@ -1033,7 +1034,7 @@ append_message_to_stream (mu_stream_t ostr, mu_message_t msg,
 			  mbox_data_t mud, int flags)
 {
   int status;
-  mu_stream_t istr;
+  mu_stream_t istr, flt;
   
   status = msg_envelope_to_stream (ostr, msg);
   if (status)
@@ -1084,10 +1085,18 @@ append_message_to_stream (mu_stream_t ostr, mu_message_t msg,
       if (status)
 	return status;
     }
-  status = mu_stream_copy (ostr, istr, 0, NULL);
-  mu_stream_destroy (&istr);
+
+  status = mu_filter_create (&flt, istr, "FROM",
+			     MU_FILTER_ENCODE, MU_STREAM_READ);
+  mu_stream_unref (istr);
   if (status == 0)
-    status = mu_stream_write (ostr, "\n", 1, NULL);
+    {
+      status = mu_stream_copy (ostr, flt, 0, NULL);
+      mu_stream_destroy (&flt);
+      if (status == 0)
+	status = mu_stream_write (ostr, "\n", 1, NULL);
+    }
+  
   return status;
 }