Add functions for operations on message sets.

* configure.ac: Build libmailutils/msgset/Makefile
* include/mailutils/msgset.h: New file.
* include/mailutils/Makefile.am (pkginclude_HEADERS): Add msgset.h
* include/mailutils/mailutils.h: Include mailutils/msgset.h
* include/mailutils/sys/msgset.h: New file.
* include/mailutils/sys/Makefile.am (sysinclude_HEADERS): Add msgset.h
* include/mailutils/types.hin (mu_msgset_t): New type.
* libmailutils/Makefile.am (SUBDIRS): Add msgset.
(libmailutils_la_LIBADD): Add libmsgset.la
* libmailutils/msgset/Makefile.am: New file.
* libmailutils/msgset/add.c: New file.
* libmailutils/msgset/aggr.c: New file.
* libmailutils/msgset/clear.c: New file.
* libmailutils/msgset/create.c: New file.
* libmailutils/msgset/free.c: New file.
* libmailutils/msgset/getitr.c: New file.
* libmailutils/msgset/getlist.c: New file.
* libmailutils/msgset/locate.c: New file.
* libmailutils/msgset/parse.c: New file.
* libmailutils/msgset/print.c: New file.
* libmailutils/msgset/sub.c: New file.
* libmailutils/tests/msgset.at: New file.
* libmailutils/tests/msgset.c: New file.
* libmailutils/tests/Makefile.am (noinst_PROGRAMS): Add msgset.
(TESTSUITE_AT): Add msgset.at.
* libmailutils/tests/testsuite.at: Include msgset.at.
* testsuite/msgset.c: New file.
* testsuite/Makefile.am (noinst_PROGRAMS): Add msgset.

@@ -1479,6 +1479,7 @@ AC_CONFIG_FILES([
  libmailutils/mailbox/Makefile
  libmailutils/mailer/Makefile
  libmailutils/mime/Makefile
+ libmailutils/msgset/Makefile
  libmailutils/property/Makefile
  libmailutils/server/Makefile
  libmailutils/string/Makefile

@@ -73,6 +73,7 @@ pkginclude_HEADERS = \
  mh.h\
  mime.h\
  monitor.h\
+ msgset.h\
  mu_auth.h\
  util.h\
  nls.h\

@@ -18,6 +18,10 @@
 #ifndef _MAILUTILS_DATETIME_H
 #define _MAILUTILS_DATETIME_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include <time.h>
 #include <mailutils/types.h>
 
@@ -83,4 +87,8 @@ int mu_scan_datetime (const char *input, const char *fmt, struct tm *tm,
 #define MU_DATETIME_FORM_RFC822  "%a, %e %b %Y %H:%M:%S %z"
 #define MU_DATETIME_SCAN_RFC822  "%[%a, %]%e %b %Y %H:%M%[:%S%] %z"
 
+#ifdef __cplusplus
+}
+#endif
+  
 #endif

@@ -70,5 +70,6 @@
 #include <mailutils/prog.h>
 #include <mailutils/sockaddr.h>
 #include <mailutils/cidr.h>
+#include <mailutils/msgset.h>
 
 /* EOF */

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 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/>. */
+
+#ifndef _MAILUTILS_MSGSET_H
+#define _MAILUTILS_MSGSET_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct mu_msgrange
+{
+  size_t msg_beg;
+  size_t msg_end;
+};
+
+/* Message numbers start with 1.  MU_MSGNO_LAST denotes the last
+   message. */
+#define MU_MSGNO_LAST   0
+  
+#define MU_MSGSET_UID   0x01   /* Message set operates on UIDs */
+  
+int mu_msgset_create (mu_msgset_t *pmsgset, mu_mailbox_t mbox, int flags);
+int mu_msgset_get_list (mu_msgset_t msgset, mu_list_t *plist);
+int mu_msgset_get_iterator (mu_msgset_t msgset, mu_iterator_t *pitr);
+
+int mu_msgset_add_range (mu_msgset_t list, size_t beg, size_t end);
+int mu_msgset_sub_range (mu_msgset_t list, size_t beg, size_t end);
+  /*int mu_msgset_add_set (mu_msgset_t a, mu_msgset_t b);*/
+  /*int mu_msgset_sub_set (mu_msgset_t a, mu_msgset_t b);*/
+int mu_msgset_aggregate (mu_msgset_t set);
+int mu_msgset_clear (mu_msgset_t set);
+void mu_msgset_free (mu_msgset_t set);
+void mu_msgset_destroy (mu_msgset_t *set);
+  
+int mu_msgset_parse_imap (mu_msgset_t set, char *s, char **end);
+
+int mu_msgset_print (mu_stream_t str, mu_msgset_t msgset);
+  
+int mu_msgset_locate (mu_msgset_t msgset, size_t n,
+		      struct mu_msgrange const **prange);
+  
+#ifdef __cplusplus
+}
+#endif
+
+#endif

@@ -44,6 +44,7 @@ sysinclude_HEADERS = \
  message.h\
  mime.h\
  monitor.h\
+ msgset.h\
  nntp.h\
  nullstream.h\
  observer.h\

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 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/>. */
+
+#ifndef _MAILUTILS_SYS_MSGSET_H
+# define _MAILUTILS_SYS_MSGSET_H
+
+#define _MU_MSGSET_AGGREGATED 0x10
+#define _MU_MSGSET_USERFLAG_MASK 0x0f
+
+struct _mu_msgset
+{
+  mu_list_t list;           /* List of mu_msgrange structures */
+  mu_mailbox_t mbox;        /* Associated mailbox */
+  int flags;                /* Message set flags */
+};
+
+#endif

@@ -77,7 +77,8 @@ struct _mu_server;
 struct _mu_tcp_server;
 struct _mu_dbm_file;
 struct _mu_imapio;
-  
+struct _mu_msgset;
+
 struct mu_sockaddr; /* defined in mailutils/sockaddr.h */  
 struct mu_cidr;     /* defined in mailutils/cidr.h */  
   
@@ -125,6 +126,7 @@ typedef struct _mu_secret *mu_secret_t;
 typedef struct _mu_mime_io_buffer *mu_mime_io_buffer_t;
 typedef struct _mu_dbm_file *mu_dbm_file_t;
 typedef struct _mu_imapio *mu_imapio_t;
+typedef struct _mu_msgset *mu_msgset_t;
 
 typedef void (*mu_onexit_t) (void*);
 typedef unsigned int mu_debug_handle_t;

@@ -18,7 +18,7 @@
 
 SUBDIRS = \
  auth base address list sockaddr cidr cfg diag\
- filter mailbox mailer mime server string stream stdstream\
+ filter mailbox mailer mime msgset server string stream stdstream\
  property url imapio datetime . tests 
 
 lib_LTLIBRARIES = libmailutils.la
@@ -41,6 +41,7 @@ libmailutils_la_LIBADD = \
  mailbox/libmailbox.la\
  mailer/libmailer.la\
  mime/libmime.la\
+ msgset/libmsgset.la\
  property/libproperty.la\
  server/libserver.la\
  string/libstring.la\

+# GNU Mailutils -- a suite of utilities for electronic mail
+# Copyright (C) 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/>.
+
+noinst_LTLIBRARIES = libmsgset.la
+
+libmsgset_la_SOURCES = \
+ add.c\
+ aggr.c\
+ clear.c\
+ create.c\
+ getitr.c\
+ getlist.c\
+ free.c\
+ locate.c\
+ parse.c\
+ print.c\
+ sub.c
+
+INCLUDES = @MU_LIB_COMMON_INCLUDES@ -I/libmailutils
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+int
+mu_msgset_add_range (mu_msgset_t mset, size_t beg, size_t end)
+{
+  int rc;
+  struct mu_msgrange *range;
+  
+  if (!mset || beg == 0)
+    return EINVAL;
+  range = calloc (1, sizeof (*range));
+  if (!range)
+    return ENOMEM;
+  range->msg_beg = beg;
+  range->msg_end = end;
+  rc = mu_list_append (mset->list, range);
+  if (rc)
+    free (range);
+  mset->flags &= ~_MU_MSGSET_AGGREGATED;
+  return rc;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/iterator.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+/* Comparator function for sorting the message set list. */
+static int
+compare_msgrange (const void *a, const void *b)
+{
+  struct mu_msgrange const *sa = a;
+  struct mu_msgrange const *sb = b;
+  
+  if (sa->msg_end != sb->msg_end)
+    {
+      if (sa->msg_end == MU_MSGNO_LAST)
+	return 1;
+      if (sb->msg_end == MU_MSGNO_LAST)
+	return -1;
+    }
+  
+  if (sa->msg_beg < sb->msg_beg)
+    return -1;
+  if (sa->msg_beg > sb->msg_beg)
+    return 1;
+
+  if (sa->msg_end == sb->msg_end)
+    return 0;
+
+  if (sa->msg_end < sb->msg_end)
+    return -1;
+  return 1;
+}
+
+int
+mu_msgset_aggregate (mu_msgset_t mset)
+{
+  int rc;
+  mu_iterator_t itr;
+  size_t count;
+  struct mu_msgrange *prev = NULL, *mr;
+  int dir;
+  
+  if (!mset)
+    return EINVAL;
+
+  if (mset->flags & _MU_MSGSET_AGGREGATED)
+    return 0; /* nothing to do */
+  
+  rc = mu_list_count (mset->list, &count);
+  if (rc)
+    return rc;
+  if (count < 2)
+    return 0;
+  
+  mu_list_sort (mset->list, compare_msgrange);
+  
+  rc = mu_list_get_iterator (mset->list, &itr);
+  if (rc)
+    return rc;
+  /* Set backward direction */
+  dir = 1;
+  rc = mu_iterator_ctl (itr, mu_itrctl_set_direction, &dir);
+  if (rc)
+    {
+      mu_iterator_destroy (&itr);
+      return rc;
+    }
+
+  mu_iterator_first (itr);
+  mu_iterator_current (itr, (void **)&mr);
+  
+  if (mr->msg_end == MU_MSGNO_LAST)
+    {
+      struct mu_msgrange *last = mr;
+      
+      for (mu_iterator_next (itr);
+	   rc == 0 && !mu_iterator_is_done (itr); mu_iterator_next (itr))
+	{
+	  mu_iterator_current (itr, (void **)&mr);
+	  if (mr->msg_end == MU_MSGNO_LAST)
+	    {
+	      last->msg_beg = mr->msg_beg;
+	      rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	    }
+	  else if (mr->msg_beg >= last->msg_beg)
+	    rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	  else if (mr->msg_end + 1 >= last->msg_beg)
+	    {
+	      last->msg_beg = mr->msg_beg;
+	      rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	    }
+	  else
+	    break;
+	}
+    }
+
+  if (rc == 0)
+    {
+      dir = 0;
+      rc = mu_iterator_ctl (itr, mu_itrctl_set_direction, &dir);
+      if (rc)
+	{
+	  mu_iterator_destroy (&itr);
+	  return rc;
+	}
+
+      for (mu_iterator_first (itr); !mu_iterator_is_done (itr);
+	   mu_iterator_next (itr))
+	{
+	  mu_iterator_current (itr, (void **)&mr);
+	  if (mr->msg_end == MU_MSGNO_LAST)
+	    break;
+	  if (prev)
+	    {
+	      if (prev->msg_beg <= mr->msg_beg && mr->msg_beg <= prev->msg_end)
+		{
+		  /* Possible cases:
+		     1. mr lies fully within prev:
+		     mr->msg_end <= prev->msg_end
+		     Action: mr deleted
+		     2. mr overlaps with prev:
+		     mr->msg_end > prev->msg_end
+		     Action: prev->msg_end is set to mr->msg_end; mr deleted
+		  */
+		  if (mr->msg_end > prev->msg_end)
+		    prev->msg_end = mr->msg_end;
+		  rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+		  if (rc)
+		    break;
+		  continue;
+		}
+	      else if (prev->msg_end + 1 == mr->msg_beg)
+		{
+		  prev->msg_end = mr->msg_end;
+		  rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+		  if (rc)
+		    break;
+		  continue;
+		}
+	    }
+	  prev = mr;
+	}
+    }
+  mu_iterator_destroy (&itr);
+
+  if (rc == 0)
+    mset->flags |= _MU_MSGSET_AGGREGATED;
+  return rc;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+int
+mu_msgset_clear (mu_msgset_t mset)
+{
+  if (!mset)
+    return EINVAL;
+  mu_list_clear (mset->list);
+  return 0;
+}
+

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+/* Comparator function used to locate a message in the list.  Second argument
+   (b) is a pointer to the message number. */
+static int
+compare_msgnum (const void *a, const void *b)
+{
+  struct mu_msgrange const *range = a;
+  size_t msgno = *(size_t*)b;
+
+  if (range->msg_beg <= msgno && msgno <= range->msg_end)
+    return 0;
+  return 1;
+}
+
+int
+mu_msgset_create (mu_msgset_t *pres, mu_mailbox_t mbox, int flags)
+{
+  mu_msgset_t msgset;
+  int rc;
+
+  msgset = calloc (1, sizeof (*msgset));
+  if (!msgset)
+    return ENOMEM;
+  
+  rc = mu_list_create (&msgset->list);
+  if (rc)
+    {
+      free (msgset);
+      return rc;
+    }
+  mu_list_set_destroy_item (msgset->list, mu_list_free_item);
+  mu_list_set_comparator (msgset->list, compare_msgnum);
+  msgset->mbox = mbox;
+  msgset->flags = flags & _MU_MSGSET_USERFLAG_MASK;
+  *pres = msgset;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+void
+mu_msgset_free (mu_msgset_t mset)
+{
+  if (mset)
+    {
+      mu_list_destroy (&mset->list);
+      free (mset);
+    }
+}
+
+void
+mu_msgset_destroy (mu_msgset_t *pset)
+{
+  if (pset)
+    {
+      mu_msgset_free (*pset);
+      *pset = NULL;
+    }
+}
+  

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+int
+mu_msgset_get_iterator (mu_msgset_t msgset, mu_iterator_t *pitr)
+{
+  if (!msgset)
+    return EINVAL;
+  return mu_list_get_iterator (msgset->list, pitr);
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+int
+mu_msgset_get_list (mu_msgset_t msgset, mu_list_t *plist)
+{
+  if (!msgset)
+    return EINVAL;
+  if (!plist)
+    return MU_ERR_OUT_PTR_NULL;
+  *plist = msgset->list;
+  return 0;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+int
+mu_msgset_locate (mu_msgset_t msgset, size_t n,
+		  struct mu_msgrange const **prange)
+{
+  if (!msgset || n == 0)
+    return EINVAL;
+  return mu_list_locate (msgset->list, &n, (void**)prange);
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/iterator.h>
+#include <mailutils/mailbox.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+/* This structure keeps parser state while parsing message set. */
+struct parse_msgnum_env
+{
+  char *s;               /* Current position in string */
+  size_t minval;         /* Min. sequence number or UID */
+  size_t maxval;         /* Max. sequence number or UID */
+  mu_msgset_t msgset;    /* Message set being built. */
+};
+
+/* Get a single message number/UID from env->s and store it into *PN.
+   Return 0 on success and error code on error.
+
+   Advance env->s to the point past the parsed message number.
+ */
+static int
+get_msgnum (struct parse_msgnum_env *env, size_t *pn)
+{
+  size_t msgnum;
+  char *p;
+  
+  errno = 0;
+  msgnum = strtoul (env->s, &p, 10);
+  if (msgnum == ULONG_MAX && errno == ERANGE)
+    return MU_ERR_PARSE;
+  env->s = p;
+  if (env->msgset->mbox && env->maxval && msgnum > env->maxval)
+    msgnum = env->maxval;
+  *pn = msgnum;
+  return 0;
+}
+
+/* Parse a single message range (A:B). Treat '*' as the largest number/UID
+   in use. */
+static int
+parse_msgrange (struct parse_msgnum_env *env)
+{
+  int rc;
+  struct mu_msgrange msgrange;
+  
+  if (*env->s == '*')
+    {
+      msgrange.msg_beg = env->maxval;
+      env->s++;
+    }
+  else if ((rc = get_msgnum (env, &msgrange.msg_beg)))
+    return rc;
+
+  if (*env->s == ':')
+    {
+      if (*++env->s == '*')
+	{
+	  msgrange.msg_end = env->maxval;
+	  ++env->s;
+	}
+      else if (*env->s == 0)
+	return MU_ERR_PARSE;
+      else if ((rc = get_msgnum (env, &msgrange.msg_end)))
+	return rc;
+    }
+  else
+    msgrange.msg_end = msgrange.msg_beg;
+
+  if (msgrange.msg_end && msgrange.msg_end < msgrange.msg_beg)
+    {
+      size_t tmp = msgrange.msg_end;
+      msgrange.msg_end = msgrange.msg_beg;
+      msgrange.msg_beg = tmp;
+    }
+
+  if ((env->msgset->flags & MU_MSGSET_UID) && env->msgset->mbox)
+    {
+      int rc;
+
+      rc = mu_mailbox_translate (env->msgset->mbox,
+				 MU_MAILBOX_UID_TO_MSGNO,
+				 msgrange.msg_beg, &msgrange.msg_beg);
+      if (rc == MU_ERR_NOENT)
+	msgrange.msg_beg = env->minval;
+      else if (rc)
+	return rc;
+      
+      rc = mu_mailbox_translate (env->msgset->mbox,
+				 MU_MAILBOX_UID_TO_MSGNO,
+				 msgrange.msg_end, &msgrange.msg_end);
+      if (rc == MU_ERR_NOENT)
+	msgrange.msg_end = env->maxval;
+      else if (rc)
+	return rc;
+    }      
+
+  return mu_msgset_add_range (env->msgset, msgrange.msg_beg, msgrange.msg_end);
+}
+
+/* Parse IMAP-style message set specification S.
+
+   On success, return 0 and populate MSET with the resulting message ranges.
+   On error, return error code and point END to the position in the input
+   string where parsing has failed. */
+int
+mu_msgset_parse_imap (mu_msgset_t mset, char *s, char **end)
+{
+  int rc;
+  struct parse_msgnum_env env;
+  
+  if (!s || !mset)
+    return EINVAL;
+  if (!*s)
+    return MU_ERR_PARSE;
+
+  memset (&env, 0, sizeof (env));
+  env.s = s;
+  env.msgset = mset;
+  env.minval = 1;
+  
+  if (end)
+    *end = s;
+  if (mset->mbox)
+    {
+      size_t lastmsgno;      /* Max. sequence number. */
+
+      rc = mu_mailbox_messages_count (mset->mbox, &lastmsgno);
+      if (rc == 0)
+	{
+	  if (mset->flags & MU_MSGSET_UID)
+	    {
+	      rc = mu_mailbox_translate (mset->mbox, MU_MAILBOX_MSGNO_TO_UID,
+					 lastmsgno, &env.maxval);
+	      if (rc == 0)
+		rc = mu_mailbox_translate (mset->mbox, MU_MAILBOX_MSGNO_TO_UID,
+					   1, &env.minval);
+	    }
+	  else
+	    env.maxval = lastmsgno;
+	}
+      if (rc)
+	return rc;
+    }
+  
+  while ((rc = parse_msgrange (&env)) == 0 && *env.s)
+    {
+      if (*env.s != ',' || *++env.s == 0)
+	{
+	  rc = MU_ERR_PARSE;
+	  break;
+	}
+    }
+
+  if (end)
+    *end = env.s;
+  return rc;
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/stream.h>
+#include <mailutils/io.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+struct print_env
+{
+  mu_stream_t stream;
+  int cont;
+};
+
+static int
+_msgrange_printer (void *item, void *data)
+{
+  int rc;
+  struct mu_msgrange *range = item;
+  struct print_env *env = data;
+
+  if (env->cont)
+    {
+      rc = mu_stream_write (env->stream, ",", 1, NULL);
+      if (rc)
+	return rc;
+    }
+  else
+    env->cont = 1;
+  if (range->msg_beg == range->msg_end)
+    rc = mu_stream_printf (env->stream, "%lu", (unsigned long) range->msg_beg);
+  else if (range->msg_end == 0)
+    rc = mu_stream_printf (env->stream, "%lu:*",
+			   (unsigned long) range->msg_beg);
+  else
+    rc = mu_stream_printf (env->stream, "%lu:%lu",
+			   (unsigned long) range->msg_beg,
+			   (unsigned long) range->msg_end);
+  return rc;
+}
+
+int
+mu_msgset_print (mu_stream_t str, mu_msgset_t mset)
+{
+  struct print_env env;
+  int rc;
+  
+  if (mu_list_is_empty (mset->list))
+    return MU_ERR_NOENT;
+  rc = mu_msgset_aggregate (mset);
+  if (rc)
+    return rc;
+  env.stream = str;
+  env.cont = 0;
+  return mu_list_foreach (mset->list, _msgrange_printer, &env);
+}

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/types.h>
+#include <mailutils/errno.h>
+#include <mailutils/list.h>
+#include <mailutils/iterator.h>
+#include <mailutils/msgset.h>
+#include <mailutils/sys/msgset.h>
+
+/* Remove range R from the set S.
+
+   There are following basic cases:
+
+   1. S does not contain R.
+
+      Return imeediately, there is nothing to do here.
+
+   2. S contains a range X that matches exactly R.
+
+      Action: Remove X entirely and return.
+
+   3. There is a range X in S such that R falls entirely within it.
+
+      Action: Split X into two ranges:
+
+         X.msg_beg   : R.msg_beg-1
+	 R.msg_end+1 : X.msg_end
+
+      and return.
+      In border cases one of the new ranges may be empty.
+
+   4. There is a range X which contains an initial subrange of R.
+
+      Action: Remove the subrange from X. If the resulting range is
+      empty, remove it. Continue iteration with X.msg_end:R.msg_end
+      in place of R.
+
+   5. There is a range X such that its initial subrange is contained
+      in R.
+
+      Action: Remove X.msg_beg:R.msg_end and return.
+
+   6. There is a range X that is contained within R.
+
+      Action: Remove X and continue.
+
+There are two special cases.  First is when R.msg_end is 0, meaning the last
+available message number in the mailbox.  In this case the problem is reduced
+to either 2 or a combination of 4 and zero or more 6.  It is handled by the
+sub_msgno_last function below.
+
+Yet another special case is when the last element of S has msg_end == 0.  If
+so, the problem is reduced to either 2 or 4.
+*/
+
+static int
+sub_msgno_last (mu_msgset_t mset, size_t beg)
+{
+  int rc;
+  struct mu_msgrange *range;
+
+  if (beg == 1)
+    mu_list_clear (mset->list);
+  else
+    {
+      mu_iterator_t itr;
+      
+      rc = mu_list_get_iterator (mset->list, &itr);
+      if (rc)
+	return rc;
+      rc = 1;
+      rc = mu_iterator_ctl (itr, mu_itrctl_set_direction, &rc);
+      if (rc)
+	{
+	  mu_iterator_destroy (&itr);
+	  return rc;
+	}
+	  
+      for (mu_iterator_first (itr); rc == 0 && !mu_iterator_is_done (itr);
+	   mu_iterator_next (itr))
+	{
+	  mu_iterator_current (itr, (void **)&range);
+	  if (range->msg_beg > beg)
+	    rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	  else if (range->msg_beg == beg)
+	    {
+	      rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	      break;
+	    }
+	  else
+	    break;
+	}
+      mu_iterator_destroy (&itr);
+    }
+  return 0;
+}
+
+int
+mu_msgset_sub_range (mu_msgset_t mset, size_t beg, size_t end)
+{
+  int rc;
+  mu_iterator_t itr;
+  struct mu_msgrange *mr;
+
+  if (!mset)
+    return EINVAL;
+  if (mu_list_is_empty (mset->list))
+    return MU_ERR_NOENT;
+  rc = mu_msgset_aggregate (mset);
+  if (rc)
+    return rc;
+
+  if (end == MU_MSGNO_LAST)
+    return sub_msgno_last (mset, beg);
+  
+  /* Test border cases */
+  rc = mu_list_head (mset->list, (void**)&mr);
+  if (rc)
+    return rc;
+  if (end < mr->msg_beg)
+    return 0;
+  if (beg < mr->msg_beg)
+    beg = mr->msg_beg;
+  
+  if (rc)
+    return rc;
+  rc = mu_list_tail (mset->list, (void**) &mr);
+  if (mr->msg_end != MU_MSGNO_LAST)
+    {
+      if (beg > mr->msg_end)
+	return 0;
+      if (end > mr->msg_end)
+	end = mr->msg_end;
+    }
+  
+  rc = mu_list_get_iterator (mset->list, &itr);
+  if (rc)
+    return rc;
+  for (mu_iterator_first (itr); rc == 0 && !mu_iterator_is_done (itr);
+       mu_iterator_next (itr))
+    {
+      mu_iterator_current (itr, (void **)&mr);
+
+      if (mr->msg_end == MU_MSGNO_LAST)
+	{
+	  /* This is the last element in list. */
+	  if (mr->msg_beg == beg)
+	    rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	  else if (mr->msg_beg > beg)
+	    mr->msg_beg = end + 1;
+	  break;
+	}
+      
+      if (mr->msg_beg == beg && mr->msg_end == end) /* See case 2 above */
+	{
+	  rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	  break;
+	}
+      else if (mr->msg_beg <= beg && beg <= mr->msg_end) 
+	{ 
+	  if (mr->msg_beg <= end && end <= mr->msg_end) /* Case 3 */
+	    {
+	      /* Split the range */
+	      if (end != mr->msg_end)
+		{
+		  struct mu_msgrange *newrange = calloc (1,
+							 sizeof (*newrange));
+		  if (!newrange)
+		    {
+		      rc = ENOMEM;
+		      break;
+		    }
+		  newrange->msg_beg = end + 1;
+		  newrange->msg_end = mr->msg_end;
+		  rc = mu_iterator_ctl (itr, mu_itrctl_insert, newrange);
+		  if (rc)
+		    {
+		      free (newrange);
+		      break;
+		    }
+		}
+	      
+	      if (mr->msg_beg == beg)
+		rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	      else
+		mr->msg_end = beg - 1;
+	      break;
+	    }
+	  else if (mr->msg_beg == beg)      /* Case 4 */
+	    {
+	      beg = mr->msg_end;
+	      rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	    }
+	  else
+	    {
+	      size_t n = mr->msg_end;
+	      mr->msg_end = beg - 1;
+	      beg = n;
+	    }
+	}
+      else if (mr->msg_beg <= end && end <= mr->msg_end) /* Case 5 */
+	{
+	  mr->msg_beg = end + 1;
+	  if (mr->msg_beg >= mr->msg_end)
+	    rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	  break;
+	}
+      else if (beg <= mr->msg_beg && mr->msg_beg <= end)
+	{
+	  rc = mu_iterator_ctl (itr, mu_itrctl_delete, NULL);
+	}
+    }
+  mu_iterator_destroy (&itr);
+  
+  return rc;
+}
+      

@@ -52,6 +52,7 @@ noinst_PROGRAMS = \
  listop\
  mailcap\
  mimehdr\
+ msgset\
  prop\
  scantime\
  strftime\
@@ -90,6 +91,7 @@ TESTSUITE_AT = \
  list.at\
  mailcap.at\
  mimehdr.at\
+ msgset.at\
  prop.at\
  scantime.at\
  strftime.at\

+# This file is part of GNU Mailutils. -*- Autotest -*-
+# Copyright (C) 2011 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.
+#
+# 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, see <http://www.gnu.org/licenses/>.
+
+AT_BANNER([Message sets])
+
+dnl ------------------------------------------------------------------
+dnl MSGSET([NAME], [KW = `'], [OP], [STDOUT = `'], [STDERR = `'])
+dnl
+m4_pushdef([MSGSET],[
+AT_SETUP([$1])
+AT_KEYWORDS([msgset $2])
+AT_CHECK([msgset $3],[0],[$4],[$5])
+AT_CLEANUP
+])
+dnl ------------------------------------------------------------------
+
+MSGSET([Aggregation: simple],[msgset-aggr-simple msgset-aggr],
+[-msgset='1,5:11,20:24,80:90,22:30,50:60,4:12,41:50,70:81'],
+[1,4:12,20:30,41:60,70:90
+])
+
+MSGSET([Aggregation: open range (1)],
+[msgset-aggr-open-1 msgset-aggr-open msgset-aggr],
+[-msgset='12:*,1'],
+[1,12:*
+])
+
+MSGSET([Aggregation: coalescing open ranges],
+[msgset-aggr-open-2 msgset-aggr-open msgset-aggr],
+[-msgset='12:*,1,15:*,8:*'],
+[1,8:*
+])
+
+MSGSET([Aggregation: open range (3)],
+[msgset-aggr-open-3 msgset-aggr-open msgset-aggr],
+[-msgset='1,12:*,12:13'],
+[1,12:*
+])
+
+MSGSET([Aggregation: open range (4)],
+[msgset-aggr-open-4 msgset-aggr-open msgset-aggr],
+[-msgset='1,12:*,13:40'],
+[1,12:*
+])
+
+MSGSET([Aggregation: open range (5)],
+[msgset-aggr-open-5 msgset-aggr-open msgset-aggr],
+[-msgset='10:*,3,5:9'],
+[3,5:*
+])
+
+MSGSET([Create simple set],[msgset-simple msgset-add],
+[-add=1:10],
+[1:10
+])
+
+MSGSET([Create complex set],[msgset-complex msgset-add],
+[-add=1 -add=2 -add=3 -add=4 -add=10:20 -add=15:35 -add=36:40],
+[1:4,10:40
+])
+
+MSGSET([Subtract: no match],[msgset-sub msgset-sub-1],
+[-msgset=20:40 -sub=1:10],
+[20:40
+])
+
+MSGSET([Subtract: exact match],[msgset-sub msgset-sub-2],
+[-msgset=1,4:9,11 -sub=4:9],
+[1,11
+])
+
+MSGSET([Subtract: contained range],[msgset-sub msgset-sub-3],
+[-msgset=1:40 -sub=5:15
+],
+[1:4,16:40
+])
+
+MSGSET([Subtract: contained range (left border case)],
+[msgset-sub msgset-sub-3 msgset-sub-3-0],
+[-msgset=1:40 -sub=1:20],
+[21:40
+])
+
+MSGSET([Subtract: contained range (right border case)],
+[msgset-sub msgset-sub-3 msgset-sub-3-1],
+[-msgset=1:40 -sub=30:40],
+[1:29
+])
+
+MSGSET([Subtract: initial subrange],[msgset-sub msgset-sub-4],
+[-msgset=1:40,50:60,80:200 -sub=55:65],
+[1:40,50:54,80:200
+])
+
+MSGSET([Subtract: trailing subrange],[msgset-sub msgset-sub-5],
+[-msgset=1:40,50:60,80:200 -sub=45:55],
+[1:40,56:60,80:200
+])
+
+MSGSET([Subtract: overlapping subrange],[msgset-sub msgset-sub-6],
+[-msgset=1:40,50:60,80:200 -sub=41:70],
+[1:40,80:200
+])
+
+MSGSET([Subtract: 4, 5 and 6 combined],
+[msgset-sub msgset-sub-4 msgset-sub-5 msgset-sub-6 msgset-sub-456],
+[-msgset=1:40,50:60,80:200 -sub=30:100],
+[1:29,101:200
+])
+
+MSGSET([open range],[msgset-inf],
+[-msgset='1:*'],
+[1:*
+])
+
+MSGSET([add to open range],[msgset-inf-add msgset-add],
+[-msgset='10:*' -add=3 -add=5:9],
+[3,5:*
+])
+
+MSGSET([subtract from open range],[msgset-inf-sub msgset-sub],
+[-msgset='3,10:*' -sub=5:11],
+[3,12:*
+])
+
+MSGSET([subtract from open range an equal range],[msgset-inf-sub-1 msgset-sub],
+[-msgset='3,10:*' -sub=10:*],
+[3
+])
+
+MSGSET([subtract from open range a broader range],
+[msgset-inf-sub-2 msgset-sub],
+[-msgset='3,10:*' -sub=20:*],
+[3,10:*
+])
+
+MSGSET([subtract from open range a narrower range],
+[msgset-inf-sub-3 msgset-sub],
+[-msgset='3,10:*' -sub=5:*],
+[3
+])
+
+MSGSET([subtract an open range with matching left boundary],
+[msgset-inf-sub-4 msgset-sub],
+[-msgset='3,10:20' -sub=10:*],
+[3
+])
+
+MSGSET([subtract an open range with greater left boundary],
+[msgset-inf-sub-4 msgset-sub],
+[-msgset='3,10:20' -sub=11:*],
+[3,10:20
+])
+
+MSGSET([subtract an open range with smaller left boundary],
+[msgset-inf-sub-4 msgset-sub],
+[-msgset='3,10:20' -sub=8:*],
+[3
+])
+
+dnl ------------------------------------------------------------------
+m4_popdef([MSGSET])
\ No newline at end of file

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/mailutils.h>
+
+static void
+parse_msgset (char *arg, struct mu_msgrange *range)
+{
+  size_t msgnum;
+  char *p;
+  
+  errno = 0;
+  msgnum = strtoul (arg, &p, 10);
+  range->msg_beg = msgnum;
+  if (*p == ':')
+    {
+      if (*++p == '*')
+	msgnum = 0;
+      else
+	{
+	  msgnum = strtoul (p, &p, 10);
+	  if (*p)
+	    {
+	      mu_error ("error in message range near %s", p);
+	      exit (1);
+	    }
+	}
+    }
+  else if (*p == '*')
+    msgnum = 0;
+  else if (*p)
+    {
+      mu_error ("error in message range near %s", p);
+      exit (1);
+    }
+
+  range->msg_end = msgnum;
+}
+
+int
+main (int argc, char **argv)
+{
+  int i;
+  char *msgset_string = NULL;
+  mu_msgset_t msgset;
+  int rc;
+  
+  mu_set_program_name (argv[0]);
+  for (i = 1; i < argc; i++)
+    {
+      char *arg = argv[i];
+
+      if (strcmp (arg, "-h") == 0 || strcmp (arg, "-help") == 0)
+	{
+	  mu_printf ("usage: %s [-msgset=SET] [-add X[:Y]] [-del X:[Y]]...\n",
+		     mu_program_name);
+	  return 0;
+	}
+      else if (strncmp (arg, "-msgset=", 8) == 0)
+	msgset_string = arg + 8;
+      else
+	break;
+    }
+
+  MU_ASSERT (mu_msgset_create (&msgset, NULL, 0));
+  if (msgset_string)
+    {
+      char *end;
+      rc = mu_msgset_parse_imap (msgset, msgset_string, &end);
+      if (rc)
+	{
+	  mu_error ("mu_msgset_parse_imap: %s near %s",
+		    mu_strerror (rc), end);
+	  return 1;
+	}
+    }
+  
+  for (; i < argc; i++)
+    {
+      char *arg = argv[i];
+      struct mu_msgrange range;
+      
+      if (strncmp (arg, "-add=", 5) == 0)
+	{
+	  parse_msgset (arg + 5, &range);
+	  MU_ASSERT (mu_msgset_add_range (msgset, range.msg_beg,
+					  range.msg_end));
+	}
+      else if (strncmp (arg, "-sub=", 5) == 0)
+	{
+	  parse_msgset (arg + 5, &range);
+	  MU_ASSERT (mu_msgset_sub_range (msgset, range.msg_beg,
+					  range.msg_end));
+	}
+      else
+      	{
+	  mu_error ("unknown option %s", arg);
+	  return 1;
+	}
+    }
+  MU_ASSERT (mu_msgset_print (mu_strout, msgset));
+  mu_printf ("\n");
+  mu_msgset_free (msgset);
+  
+  return 0;
+}
+  
+	     
+
+	

@@ -99,3 +99,5 @@ m4_include([strftime.at])
 m4_include([fsaf.at])
 
 m4_include([mimehdr.at])
+
+m4_include([msgset.at])

@@ -54,6 +54,7 @@ noinst_PROGRAMS = \
  fldel\
  lstuid\
  mbdel\
+ msgset\
  mimetest\
  smtpsend\
  ufms

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2011 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.
+
+   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, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+#include <stdlib.h>
+#include <mailutils/mailutils.h>
+
+static void
+parse_msgset (char *arg, struct mu_msgrange *range)
+{
+  size_t msgnum;
+  char *p;
+  
+  errno = 0;
+  msgnum = strtoul (arg, &p, 10);
+  range->msg_beg = msgnum;
+  if (*p == ':')
+    {
+      if (*++p == '*')
+	msgnum = 0;
+      else
+	{
+	  msgnum = strtoul (p, &p, 10);
+	  if (*p)
+	    {
+	      mu_error ("error in message range near %s", p);
+	      exit (1);
+	    }
+	}
+    }
+  else if (*p == '*')
+    msgnum = 0;
+  else if (*p)
+    {
+      mu_error ("error in message range near %s", p);
+      exit (1);
+    }
+
+  range->msg_end = msgnum;
+}
+
+int
+main (int argc, char **argv)
+{
+  int i;
+  char *msgset_string = NULL;
+  mu_msgset_t msgset;
+  int rc;
+  int flags = 0;
+  mu_mailbox_t mbox = NULL;
+  
+  mu_set_program_name (argv[0]);
+  mu_registrar_record (mu_mbox_record);
+  for (i = 1; i < argc; i++)
+    {
+      char *arg = argv[i];
+
+      if (strcmp (arg, "-h") == 0 || strcmp (arg, "-help") == 0)
+	{
+	  mu_printf ("usage: %s [-msgset=SET] [-add X[:Y]] [-del X:[Y]]...\n",
+		     mu_program_name);
+	  return 0;
+	}
+      else if (strncmp (arg, "-msgset=", 8) == 0)
+	msgset_string = arg + 8;
+      else if (strcmp (arg, "-uid") == 0)
+	flags |= MU_MSGSET_UID;
+      else if (strncmp (arg, "-mailbox=", 9) == 0)
+	{
+	  MU_ASSERT (mu_mailbox_create (&mbox, arg + 9));
+	  MU_ASSERT (mu_mailbox_open (mbox, MU_STREAM_READ));
+	}
+      else
+	break;
+    }
+
+  MU_ASSERT (mu_msgset_create (&msgset, mbox, flags));
+  if (msgset_string)
+    {
+      char *end;
+      rc = mu_msgset_parse_imap (msgset, msgset_string, &end);
+      if (rc)
+	{
+	  mu_error ("mu_msgset_parse_imap: %s near %s",
+		    mu_strerror (rc), end);
+	  return 1;
+	}
+    }
+  
+  for (; i < argc; i++)
+    {
+      char *arg = argv[i];
+      struct mu_msgrange range;
+      
+      if (strncmp (arg, "-add=", 5) == 0)
+	{
+	  parse_msgset (arg + 5, &range);
+	  MU_ASSERT (mu_msgset_add_range (msgset, range.msg_beg,
+					  range.msg_end));
+	}
+      else if (strncmp (arg, "-sub=", 5) == 0)
+	{
+	  parse_msgset (arg + 5, &range);
+	  MU_ASSERT (mu_msgset_sub_range (msgset, range.msg_beg,
+					  range.msg_end));
+	}
+      else
+      	{
+	  mu_error ("unknown option %s", arg);
+	  return 1;
+	}
+    }
+  MU_ASSERT (mu_msgset_print (mu_strout, msgset));
+  mu_printf ("\n");
+  mu_msgset_free (msgset);
+  
+  return 0;
+}
+  
+	     
+
+