Mh-specific message sets.

+/* GNU mailutils - a suite of utilities for electronic mail
+   Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
+
+   This program 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.
+
+   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 this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+/* MH message sets. */
+
+#include <mh.h>
+
+static void
+_expand (size_t *msgcnt, size_t **msglist, size_t inc)
+{
+  if (!inc)
+    return;
+
+  *msgcnt += inc;
+  *msglist = realloc (*msglist, (*msgcnt)*sizeof(**msglist));
+  if (!*msglist)
+    {
+      mh_error ("not enough memory");
+      abort ();
+    }
+}
+
+static void
+msgset_abort (const char *arg)
+{
+  mh_error ("bad message list `%s'", arg);
+  exit (1);
+}
+
+static int
+msgset_first (mailbox_t mbox, size_t *pnum)
+{
+  *pnum = 1;
+  return 0;
+}
+
+static int
+msgset_last (mailbox_t mbox, size_t *pnum)
+{
+  int rc;
+  size_t count = 0;
+
+  rc = mailbox_messages_count (mbox, &count);
+  if (rc)
+    {
+      mh_error ("can't get last message: %s", mu_errstring (rc));
+      exit (1);
+    }
+  *pnum = count;
+  return 0;
+}
+
+static int
+msgset_cur (mailbox_t mbox, size_t *pnum)
+{
+  size_t i, count = 0;
+  static int cached_n = 0;
+
+  if (cached_n)
+    {
+      *pnum = cached_n;
+      return 0;
+    }
+  
+  mailbox_messages_count (mbox, &count);
+  for (i = 1; i <= count; i++)
+    {
+      message_t msg = NULL;
+      size_t uid = 0;
+      
+      mailbox_get_message (mbox, i, &msg);
+      mh_message_number (msg, &uid);
+      if (uid == current_message)
+	{
+	  *pnum = cached_n = i;
+	  return 0;
+	}
+    }
+  mh_error ("no cur message");
+  exit (1);
+}
+
+static int
+msgset_prev (mailbox_t mbox, size_t *pnum)
+{
+  size_t cur_n = 0;
+  msgset_cur (mbox, &cur_n);
+  if (cur_n < 1)
+    {
+      mh_error ("mo prev message");
+      exit (1);
+    }
+  *pnum = cur_n - 1;
+  return 0;
+}
+
+static int
+msgset_next (mailbox_t mbox, size_t *pnum)
+{
+  size_t cur_n = 0, total = 0;
+  msgset_cur (mbox, &cur_n);
+  mailbox_messages_count (mbox, &total);
+  if (cur_n + 1 > total)
+    {
+      mh_error ("mo next message");
+      exit (1);
+    }
+  *pnum = cur_n + 1;
+  return 0;
+}
+
+static struct msgset_keyword {
+  char *name;
+  int (*handler) __P((mailbox_t mbox, size_t *pnum));
+} keywords[] = {
+  { "first", msgset_first },
+  { "last", msgset_last },
+  { "prev", msgset_prev },
+  { "next", msgset_next },
+  { "cur", msgset_cur },
+  { NULL },
+};
+
+static char *
+msgset_preproc (mailbox_t mbox, char *arg)
+{
+  struct msgset_keyword *p;
+  
+  for (p = keywords; p->name; p++)
+    if (strncmp (arg, p->name, strlen (p->name)) == 0)
+      {
+	int rc;
+	size_t uid, num;
+	char *ret = NULL;
+	message_t msg;
+	
+	if (p->handler (mbox, &num))
+	  msgset_abort (arg);
+	rc = mailbox_get_message (mbox, num, &msg);
+	if (rc)
+	  {
+	    mh_error ("can't get message %d: %s", num, mu_errstring (rc));
+	    exit (1);
+	  }
+	message_get_uid (msg, &uid);
+	asprintf (&ret, "%lu%s", (unsigned long) uid, arg + strlen (p->name));
+	return ret;
+      }
+  return strdup (arg);
+}
+
+int
+mh_msgset_parse (mailbox_t mbox, mh_msgset_t *msgset, int argc, char **argv)
+{
+  size_t msgcnt;
+  size_t *msglist;
+  char *xargv[2];
+  size_t i, msgno;
+  
+  if (argc == 0)
+    {
+      argc = 1;
+      argv = xargv;
+      argv[0] = "cur";
+      argv[1] = NULL;
+    }
+  
+  msgcnt = argc;
+  msglist = calloc (msgcnt, sizeof(*msglist));
+  for (i = 0, msgno = 0; i < argc; i++)
+    {
+      char *p = NULL;
+      size_t start, end;
+      long num;
+      char *arg = msgset_preproc (mbox, argv[i]);
+      start = strtoul (arg, &p, 0);
+      switch (*p)
+	{
+	case 0:
+	  msglist[msgno++] = start;
+	  break;
+	  
+	case '-':
+	  end = strtoul (p+1, &p, 0);
+	  if (*p || end == start)
+	    msgset_abort (argv[i]);
+	  if (end < start)
+	    {
+	      size_t t = start;
+	      start = end;
+	      end = t;
+	    }
+	  _expand (&msgcnt, &msglist, end - start);
+	  for (; start <= end; start++)
+	    msglist[msgno++] = start;
+	  break;
+	  
+	case ':':
+	  num = strtoul (p+1, &p, 0);
+	  if (*p)
+	    msgset_abort (argv[i]);
+	  end = start + num;
+	  if (end < start)
+	    {
+	      size_t t = start;
+	      start = end;
+	      end = t;
+	    }
+	  _expand (&msgcnt, &msglist, end - start);
+	  for (; start <= end; start++)
+	    msglist[msgno++] = start;
+	  break;
+	  
+	default:
+	  msgset_abort (argv[i]);
+	}
+      free (arg);
+    }
+
+  msgset->count = msgcnt;
+  msgset->list = msglist;
+  return 0;
+}
+
+int
+mh_msgset_member (mh_msgset_t *msgset, size_t num)
+{
+  size_t i;
+
+  for (i = 0; i < msgset->count; i++)
+    if (msgset->list[i] == num)
+      return i + 1;
+  return 0;
+}