libiptc2/linux_listhelp.h

   1 #ifndef _LINUX_LISTHELP_H
   2 #define _LINUX_LISTHELP_H
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include "linux_list.h"
   6
   7 /* Header to do more comprehensive job than linux/list.h; assume list
   8    is first entry in structure. */
   9
  10 /* Return pointer to first true entry, if any, or NULL.  A macro
  11    required to allow inlining of cmpfn. */
  12 #define LIST_FIND(head, cmpfn, type, args...)           \
  13 ({                                                      \
  14         const struct list_head *__i = (head);           \
  15                                                         \
  16         do {                                            \
  17                 __i = __i->next;                        \
  18                 if (__i == (head)) {                    \
  19                         __i = NULL;                     \
  20                         break;                          \
  21                 }                                       \
  22         } while (!cmpfn((const type)__i , ## args));    \
  23         (type)__i;                                      \
  24 })
  25
  26 #define LIST_FIND_W(head, cmpfn, type, args...) \
  27 ({                                              \
  28         const struct list_head *__i = (head);   \
  29                                                 \
  30         do {                                    \
  31                 __i = __i->next;                \
  32                 if (__i == (head)) {            \
  33                         __i = NULL;             \
  34                         break;                  \
  35                 }                               \
  36         } while (!cmpfn((type)__i , ## args));  \
  37         (type)__i;                              \
  38 })
  39
  40 static inline int
  41 __list_cmp_same(const void *p1, const void *p2) { return p1 == p2; }
  42
  43 /* Is this entry in the list? */
  44 static inline int
  45 list_inlist(struct list_head *head, const void *entry)
  46 {
  47         return LIST_FIND(head, __list_cmp_same, void *, entry) != NULL;
  48 }
  49
  50 /* Delete from list. */
  51 #define LIST_DELETE(head, oldentry) list_del((struct list_head *)oldentry)
  52
  53 /* Append. */
  54 static inline void
  55 list_append(struct list_head *head, void *new)
  56 {
  57         list_add((new), (head)->prev);
  58 }
  59
  60 /* Prepend. */
  61 static inline void
  62 list_prepend(struct list_head *head, void *new)
  63 {
  64         list_add(new, head);
  65 }
  66
  67 /* Insert according to ordering function; insert before first true. */
  68 #define LIST_INSERT(head, new, cmpfn)                           \
  69 do {                                                            \
  70         struct list_head *__i;                                  \
  71         for (__i = (head)->next;                                \
  72              !cmpfn((new), (typeof (new))__i) && __i != (head); \
  73              __i = __i->next);                                  \
  74         list_add((struct list_head *)(new), __i->prev);         \
  75 } while(0)
  76
  77 /* If the field after the list_head is a nul-terminated string, you
  78    can use these functions. */
  79 static inline int __list_cmp_name(const void *i, const char *name)
  80 {
  81         return strcmp(name, i+sizeof(struct list_head)) == 0;
  82 }
  83
  84 /* Returns false if same name already in list, otherwise does insert. */
  85 static inline int
  86 list_named_insert(struct list_head *head, void *new)
  87 {
  88         if (LIST_FIND(head, __list_cmp_name, void *,
  89                       new + sizeof(struct list_head)))
  90                 return 0;
  91         list_prepend(head, new);
  92         return 1;
  93 }
  94
  95 /* Find this named element in the list. */
  96 #define list_named_find(head, name)                     \
  97 LIST_FIND(head, __list_cmp_name, void *, name)
  98
  99 #endif /*_LISTHELP_H*/