Line data    Source code

       1             : /* list.c - Functions for manipulating linked lists of objects. */
       2             : 
       3             : /* Copyright (C) 1996-2009 Free Software Foundation, Inc.
       4             : 
       5             :    This file is part of GNU Bash, the Bourne Again SHell.
       6             : 
       7             :    Bash is free software: you can redistribute it and/or modify
       8             :    it under the terms of the GNU General Public License as published by
       9             :    the Free Software Foundation, either version 3 of the License, or
      10             :    (at your option) any later version.
      11             : 
      12             :    Bash is distributed in the hope that it will be useful,
      13             :    but WITHOUT ANY WARRANTY; without even the implied warranty of
      14             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      15             :    GNU General Public License for more details.
      16             : 
      17             :    You should have received a copy of the GNU General Public License
      18             :    along with Bash.  If not, see <http://www.gnu.org/licenses/>.
      19             : */
      20             : 
      21             : #include "config.h"
      22             : 
      23             : #if defined (HAVE_UNISTD_H)
      24             : #  ifdef _MINIX
      25             : #    include <sys/types.h>
      26             : #  endif
      27             : #  include <unistd.h>
      28             : #endif
      29             : 
      30             : #include "shell.h"
      31             : 
      32             : /* A global variable which acts as a sentinel for an `error' list return. */
      33             : GENERIC_LIST global_error_list;
      34             : 
      35             : #ifdef INCLUDE_UNUSED
      36             : /* Call FUNCTION on every member of LIST, a generic list. */
      37             : void
      38             : list_walk (list, function)
      39             :      GENERIC_LIST *list;
      40             :      sh_glist_func_t *function;
      41             : {
      42             :   for ( ; list; list = list->next)
      43             :     if ((*function) (list) < 0)
      44             :       return;
      45             : }
      46             : 
      47             : /* Call FUNCTION on every string in WORDS. */
      48             : void
      49             : wlist_walk (words, function)
      50             :      WORD_LIST *words;
      51             :      sh_icpfunc_t *function;
      52             : {
      53             :   for ( ; words; words = words->next)
      54             :     if ((*function) (words->word->word) < 0)
      55             :       return;
      56             : }
      57             : #endif /* INCLUDE_UNUSED */
      58             : 
      59             : /* Reverse the chain of structures in LIST.  Output the new head
      60             :    of the chain.  You should always assign the output value of this
      61             :    function to something, or you will lose the chain. */
      62             : GENERIC_LIST *
      63   470040056 : list_reverse (list)
      64             :      GENERIC_LIST *list;
      65             : {
      66   470040056 :   register GENERIC_LIST *next, *prev;
      67             : 
      68  1957319659 :   for (prev = (GENERIC_LIST *)NULL; list; )
      69             :     {
      70  1487279603 :       next = list->next;
      71  1487279603 :       list->next = prev;
      72  1487279603 :       prev = list;
      73  1487279603 :       list = next;
      74             :     }
      75   470040056 :   return (prev);
      76             : }
      77             : 
      78             : /* Return the number of elements in LIST, a generic list. */
      79             : int
      80    25677799 : list_length (list)
      81             :      GENERIC_LIST *list;
      82             : {
      83    25677799 :   register int i;
      84             : 
      85   102792881 :   for (i = 0; list; list = list->next, i++);
      86    25677799 :   return (i);
      87             : }
      88             : 
      89             : /* Append TAIL to HEAD.  Return the header of the list. */
      90             : GENERIC_LIST *
      91   163700420 : list_append (head, tail)
      92             :      GENERIC_LIST *head, *tail;
      93             : {
      94   163700420 :   register GENERIC_LIST *t_head;
      95             : 
      96   163700420 :   if (head == 0)
      97             :     return (tail);
      98             : 
      99   164195859 :   for (t_head = head; t_head->next; t_head = t_head->next)
     100             :     ;
     101   163664767 :   t_head->next = tail;
     102   163664767 :   return (head);
     103             : }
     104             : 
     105             : #ifdef INCLUDE_UNUSED
     106             : /* Delete the element of LIST which satisfies the predicate function COMPARER.
     107             :    Returns the element that was deleted, so you can dispose of it, or -1 if
     108             :    the element wasn't found.  COMPARER is called with the list element and
     109             :    then ARG.  Note that LIST contains the address of a variable which points
     110             :    to the list.  You might call this function like this:
     111             : 
     112             :    SHELL_VAR *elt = list_remove (&variable_list, check_var_has_name, "foo");
     113             :    dispose_variable (elt);
     114             : */
     115             : GENERIC_LIST *
     116             : list_remove (list, comparer, arg)
     117             :      GENERIC_LIST **list;
     118             :      Function *comparer;
     119             :      char *arg;
     120             : {
     121             :   register GENERIC_LIST *prev, *temp;
     122             : 
     123             :   for (prev = (GENERIC_LIST *)NULL, temp = *list; temp; prev = temp, temp = temp->next)
     124             :     {
     125             :       if ((*comparer) (temp, arg))
     126             :         {
     127             :           if (prev)
     128             :             prev->next = temp->next;
     129             :           else
     130             :             *list = temp->next;
     131             :           return (temp);
     132             :         }
     133             :     }
     134             :   return ((GENERIC_LIST *)&global_error_list);
     135             : }
     136             : #endif