Imported from ../bash-2.0.tar.gz.

list.c

@@ -0,0 +1,128 @@
+/* list.c - Functions for manipulating linked lists of objects. */
+
+/* Copyright (C) 1996
+   Free Software Foundation, Inc.
+
+   This file is part of GNU Bash, the Bourne Again SHell.
+
+   Bash 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.
+
+   Bash 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 Bash; see the file COPYING.  If not, write to the Free Software
+   Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include "config.h"
+
+#if defined (HAVE_UNISTD_H)
+#  include <unistd.h>
+#endif
+
+#include "shell.h"
+
+/* A global variable which acts as a sentinel for an `error' list return. */
+GENERIC_LIST global_error_list;
+
+/* Call FUNCTION on every member of LIST, a generic list. */
+void
+map_over_list (list, function)
+     GENERIC_LIST *list;
+     Function *function;
+{
+  for ( ; list; list = list->next)
+    (*function) (list);
+}
+
+/* Call FUNCTION on every string in WORDS. */
+void
+map_over_words (words, function)
+     WORD_LIST *words;
+     Function *function;
+{
+  for ( ; words; words = words->next)
+    (*function) (words->word->word);
+}
+
+/* Reverse the chain of structures in LIST.  Output the new head
+   of the chain.  You should always assign the output value of this
+   function to something, or you will lose the chain. */
+GENERIC_LIST *
+reverse_list (list)
+     GENERIC_LIST *list;
+{
+  register GENERIC_LIST *next, *prev;
+
+  for (prev = (GENERIC_LIST *)NULL; list; )
+    {
+      next = list->next;
+      list->next = prev;
+      prev = list;
+      list = next;
+    }
+  return (prev);
+}
+
+/* Return the number of elements in LIST, a generic list. */
+int
+list_length (list)
+     GENERIC_LIST *list;
+{
+  register int i;
+
+  for (i = 0; list; list = list->next, i++);
+  return (i);
+}
+
+/* Append TAIL to HEAD.  Return the header of the list. */
+GENERIC_LIST *
+list_append (head, tail)
+     GENERIC_LIST *head, *tail;
+{
+  register GENERIC_LIST *t_head;
+
+  if (head == 0)
+    return (tail);
+
+  for (t_head = head; t_head->next; t_head = t_head->next)
+    ;
+  t_head->next = tail;
+  return (head);
+}
+
+/* Delete the element of LIST which satisfies the predicate function COMPARER.
+   Returns the element that was deleted, so you can dispose of it, or -1 if
+   the element wasn't found.  COMPARER is called with the list element and
+   then ARG.  Note that LIST contains the address of a variable which points
+   to the list.  You might call this function like this:
+
+   SHELL_VAR *elt = delete_element (&variable_list, check_var_has_name, "foo");
+   dispose_variable (elt);
+*/
+GENERIC_LIST *
+delete_element (list, comparer, arg)
+     GENERIC_LIST **list;
+     Function *comparer;
+     char *arg;
+{
+  register GENERIC_LIST *prev, *temp;
+
+  for (prev = (GENERIC_LIST *)NULL, temp = *list; temp; prev = temp, temp = temp->next)
+    {
+      if ((*comparer) (temp, arg))
+	{
+	  if (prev)
+	    prev->next = temp->next;
+	  else
+	    *list = temp->next;
+	  return (temp);
+	}
+    }
+  return ((GENERIC_LIST *)&global_error_list);
+}