New file. A test shell for list operations

+/* GNU Mailutils -- a suite of utilities for electronic mail
+   Copyright (C) 2003 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  */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <mailutils/argcv.h>
+#include <mailutils/mailutils.h>
+
+void
+usage(int code)
+{
+  printf ("usage: listop [item..]\n");
+  exit (code);
+}
+
+void
+lperror (char *text, int rc)
+{
+  fprintf (stderr, "%s: %s\n", text, mu_strerror (rc));
+  exit (1);
+}
+
+void
+print (list_t list)
+{
+  iterator_t itr;
+  int rc;
+  
+  rc = iterator_create (&itr, list);
+  if (rc)
+    lperror ("iterator_create", rc);
+
+  for (iterator_first (itr); !iterator_is_done (itr); iterator_next (itr))
+    {
+      char *text;
+
+      rc = iterator_current (itr, (void**) &text);
+      if (rc)
+	lperror ("iterator_current", rc);
+      printf ("%s\n", text);
+    }
+  iterator_destroy (&itr);
+}
+
+void
+next (iterator_t itr, char *arg)
+{
+  int skip = arg ? strtoul (arg, NULL, 0) :  1;
+
+  if (skip == 0)
+    fprintf (stderr, "next arg?\n");
+  while (skip--)
+    iterator_next (itr);
+}
+
+void
+delete (list_t list, int argc, char **argv)
+{
+  int rc;
+
+  if (argc == 1)
+    {
+      fprintf (stderr, "del arg?\n");
+      return;
+    }
+
+  while (--argc)
+    {
+      rc = list_remove (list, strdup (*++argv));
+      if (rc)
+	fprintf (stderr, "list_remove(%s): %s\n", *argv, mu_strerror (rc));
+    }
+}
+
+void
+add (list_t list, int argc, char **argv)
+{
+  int rc;
+  
+  if (argc == 1)
+    {
+      fprintf (stderr, "add arg?\n");
+      return;
+    }
+
+  while (--argc)
+    {
+      rc = list_append (list, strdup (*++argv));
+      if (rc)
+	fprintf (stderr, "list_append: %s\n", mu_strerror (rc));
+    }
+}
+
+void
+prep (list_t list, int argc, char **argv)
+{
+  int rc;
+  
+  if (argc == 1)
+    {
+      fprintf (stderr, "add arg?\n");
+      return;
+    }
+
+  while (--argc)
+    {
+      rc = list_prepend (list, strdup (*++argv));
+      if (rc)
+	fprintf (stderr, "list_append: %s\n", mu_strerror (rc));
+    }
+}
+
+void
+repl (list_t list, int argc, char **argv)
+{
+  int rc;
+  
+  if (argc != 3)
+    {
+      fprintf (stderr, "repl src dst?\n");
+      return;
+    }
+
+  rc = list_replace (list, argv[1], strdup (argv[2]));
+  if (rc)
+    fprintf (stderr, "list_replace: %s\n", mu_strerror (rc));
+}
+
+#define NITR 4
+
+void
+iter (int *pnum, int argc, char **argv)
+{
+  int n;
+  
+  if (argc != 2)
+    {
+      fprintf (stderr, "iter num?\n");
+      return;
+    }
+
+  n = strtoul (argv[1], NULL, 0);
+  if (n < 0 || n >= NITR)
+    {
+      fprintf (stderr, "iter [0-3]?\n");
+      return;
+    }
+  *pnum = n;
+}
+
+void
+find (iterator_t itr, char *arg)
+{
+  char *text;
+  
+  if (!arg)
+    {
+      fprintf (stderr, "find item?\n");
+      return;
+    }
+
+  iterator_current (itr, (void**)&text);
+  for (iterator_first (itr); !iterator_is_done (itr); iterator_next (itr))
+    {
+      char *item;
+
+      iterator_current (itr, (void**)&item);
+      if (strcmp (arg, item) == 0)
+	return;
+    }
+
+  fprintf (stderr, "%s not in list\n", arg);
+  
+  for (iterator_first (itr); !iterator_is_done (itr); iterator_next (itr))
+    {
+      char *item;
+
+      iterator_current (itr, (void**)&item);
+      if (strcmp (text, item) == 0)
+	return;
+    }
+}
+
+void
+help ()
+{
+  printf ("next [count]\n");
+  printf ("first\n");
+  printf ("find item\n");
+  printf ("del item [item...]\n");
+  printf ("add item [item...]\n");
+  printf ("prep item [item...]\n");
+  printf ("repl old_item new_item\n");
+  printf ("print\n");
+  printf ("quit\n");
+  printf ("iter num\n");
+  printf ("help\n");
+  printf ("NUMBER\n");
+}
+
+void
+shell (list_t list)
+{
+  int num = 0;
+  iterator_t itr[NITR];
+  int rc;
+
+  for (num = 0; num < NITR; num++)
+    {
+      rc = iterator_create (&itr[num], list);
+      if (rc)
+	lperror ("iterator_create", rc);
+      iterator_first (itr[num]);
+    }
+
+  num = 0;
+  while (1)
+    {
+      char *text;
+      char buf[80];
+      int argc;
+      char **argv;
+      
+      rc = iterator_current (itr[num], (void**) &text);
+      if (rc)
+	lperror ("iterator_current", rc);
+
+      printf ("%d:(%s)> ", num, text ? text : "NULL");
+      if (fgets (buf, sizeof buf, stdin) == NULL)
+	return;
+
+      rc = argcv_get (buf, "", "#", &argc, &argv);
+      if (rc)
+	lperror ("argcv_get", rc);
+
+      if (argc > 0)
+	{
+	  if (strcmp (argv[0], "next") == 0)
+	    next (itr[num], argv[1]);
+	  else if (strcmp (argv[0], "first") == 0)
+	    iterator_first (itr[num]);
+	  else if (strcmp (argv[0], "del") == 0)
+	    delete (list, argc, argv);
+	  else if (strcmp (argv[0], "add") == 0)
+	    add (list, argc, argv);
+	  else if (strcmp (argv[0], "prep") == 0)
+	    prep (list, argc, argv);
+	  else if (strcmp (argv[0], "repl") == 0)
+	    repl (list, argc, argv);
+	  else if (strcmp (argv[0], "print") == 0)
+	    print (list);
+	  else if (strcmp (argv[0], "quit") == 0)
+	    return;
+	  else if (strcmp (argv[0], "iter") == 0)
+	    iter (&num, argc, argv);
+	  else if (strcmp (argv[0], "find") == 0)
+	    find (itr[num], argv[1]);
+	  else if (strcmp (argv[0], "help") == 0)
+	    help ();
+	  else if (argc == 1)
+	    {
+	      char *p;
+	      size_t n = strtoul (argv[0], &p, 0);
+	      if (*p != 0)
+		fprintf (stderr, "?\n");
+	      else
+		{
+		  rc = list_get (list, n, (void**) &text);
+		  if (rc)
+		    fprintf (stderr, "list_get: %s\n", mu_strerror (rc));
+		  else
+		    printf ("%s\n", text);
+		}
+	    }
+	  else
+	    fprintf (stderr, "?\n");
+	}
+      argcv_free (argc, argv);
+    }
+}
+
+static int
+string_comp (const void *item, const void *value)
+{
+  return strcmp (item, value);
+}
+
+int
+main (int argc, char **argv)
+{
+  list_t list;
+  int rc;
+  
+  while ((rc = getopt (argc, argv, "h")) != EOF)
+    switch (rc)
+      {
+      case 'h':
+	usage (0);
+	
+      default:
+	usage (1);
+      }
+
+  argc -= optind;
+  argv += optind;
+
+  rc = list_create (&list);
+  if (rc)
+    lperror ("list_create", rc);
+  list_set_comparator (list, string_comp);
+
+  while (argc--)
+    {
+      rc = list_append (list, *argv++);
+      if (rc)
+	lperror ("list_append", rc);
+    }
+
+  shell (list);
+  
+  return 0;
+}