libobjc/objc/objc-list.h

   1 /* Generic single linked list to keep various information
   2    Copyright (C) 1993, 1994, 1996 Free Software Foundation, Inc.
   3    Contributed by Kresten Krab Thorup.
   4
   5 This file is part of GCC.
   6
   7 GCC 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 2, or (at your option)
  10 any later version.
  11
  12 GCC 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 GCC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 /* As a special exception, if you link this library with files compiled with
  23    GCC to produce an executable, this does not cause the resulting executable
  24    to be covered by the GNU General Public License. This exception does not
  25    however invalidate any other reasons why the executable file might be
  26    covered by the GNU General Public License.  */
  27
  28 #ifndef __GNU_OBJC_LIST_H
  29 #define __GNU_OBJC_LIST_H
  30
  31 #ifdef __cplusplus
  32 extern "C" {
  33 #endif /* __cplusplus */
  34
  35 struct objc_list {
  36   void *head;
  37   struct objc_list *tail;
  38 };
  39
  40 /* Return a cons cell produced from (head . tail) */
  41
  42 static inline struct objc_list*
  43 list_cons(void* head, struct objc_list* tail)
  44 {
  45   struct objc_list* cell;
  46
  47   cell = (struct objc_list*)objc_malloc(sizeof(struct objc_list));
  48   cell->head = head;
  49   cell->tail = tail;
  50   return cell;
  51 }
  52
  53 /* Return the length of a list, list_length(NULL) returns zero */
  54
  55 static inline int
  56 list_length(struct objc_list* list)
  57 {
  58   int i = 0;
  59   while(list)
  60     {
  61       i += 1;
  62       list = list->tail;
  63     }
  64   return i;
  65 }
  66
  67 /* Return the Nth element of LIST, where N count from zero.  If N
  68    larger than the list length, NULL is returned  */
  69
  70 static inline void*
  71 list_nth(int indx, struct objc_list* list)
  72 {
  73   while(indx-- != 0)
  74     {
  75       if(list->tail)
  76         list = list->tail;
  77       else
  78         return 0;
  79     }
  80   return list->head;
  81 }
  82
  83 /* Remove the element at the head by replacing it by its successor */
  84
  85 static inline void
  86 list_remove_head(struct objc_list** list)
  87 {
  88   if ((*list)->tail)
  89     {
  90       struct objc_list* tail = (*list)->tail; /* fetch next */
  91       *(*list) = *tail;         /* copy next to list head */
  92       objc_free(tail);                  /* free next */
  93     }
  94   else                          /* only one element in list */
  95     {
  96       objc_free(*list);
  97       (*list) = 0;
  98     }
  99 }
 100
 101
 102 /* Remove the element with `car' set to ELEMENT */
 103
 104 static inline void
 105 list_remove_elem(struct objc_list** list, void* elem)
 106 {
 107   while (*list) {
 108     if ((*list)->head == elem)
 109       list_remove_head(list);
 110     list = &((*list)->tail);
 111   }
 112 }
 113
 114 /* Map FUNCTION over all elements in LIST */
 115
 116 static inline void
 117 list_mapcar(struct objc_list* list, void(*function)(void*))
 118 {
 119   while(list)
 120     {
 121       (*function)(list->head);
 122       list = list->tail;
 123     }
 124 }
 125
 126 /* Return element that has ELEM as car */
 127
 128 static inline struct objc_list**
 129 list_find(struct objc_list** list, void* elem)
 130 {
 131   while(*list)
 132     {
 133     if ((*list)->head == elem)
 134       return list;
 135     list = &((*list)->tail);
 136     }
 137   return NULL;
 138 }
 139
 140 /* Free list (backwards recursive) */
 141
 142 static void
 143 list_free(struct objc_list* list)
 144 {
 145   if(list)
 146     {
 147       list_free(list->tail);
 148       objc_free(list);
 149     }
 150 }
 151
 152 #ifdef __cplusplus
 153 }
 154 #endif /* __cplusplus */
 155
 156 #endif /* not __GNU_OBJC_LIST_H */