git.ozlabs.org Git - ccan/blob - ccan/htable/htable_type.h

   1 /* Licensed under LGPLv2+ - see LICENSE file for details */
   2 #ifndef CCAN_HTABLE_TYPE_H
   3 #define CCAN_HTABLE_TYPE_H
   4 #include <ccan/htable/htable.h>
   5 #include "config.h"
   6
   7 /**
   8  * HTABLE_DEFINE_TYPE - create a set of htable ops for a type
   9  * @type: a type whose pointers will be values in the hash.
  10  * @keyof: a function/macro to extract a key from a @type element.
  11  * @hashfn: a hash function for a @key
  12  * @cmpfn: a comparison function for two keyof()s.
  13  * @name: a name for all the functions to define (of form htable_<name>_*)
  14  *
  15  * NULL values may not be placed into the hash table.
  16  *
  17  * The following wrapper functions are defined; each one is a
  18  * simplified version of the htable.h equivalent:
  19  *
  20  *      // Creating and freeing.
  21  *      struct htable_@name *htable_@name_new(void);
  22  *      void htable_@name_free(const struct htable_@name *ht);
  23  *
  24  *      // Add, delete and find.
  25  *      bool htable_@name_add(struct htable_@name *ht, const type *e);
  26  *      bool htable_@name_del(struct htable_@name *ht, const type *e);
  27  *      bool htable_@name_delkey(struct htable_@name *ht, const ktype *k);
  28  *      type *htable_@name_get(const struct htable_@name *ht, const ktype *k);
  29  *
  30  *      // Iteration.
  31  *      struct htable_@name_iter;
  32  *      type *htable_@name_first(const struct htable_@name *ht,
  33  *                               struct htable_@name_iter *i);
  34  *      type *htable_@name_next(const struct htable_@name *ht,
  35  *                              struct htable_@name_iter *i);
  36  */
  37 #define HTABLE_DEFINE_TYPE(type, keyof, hashfn, cmpfn, name)            \
  38 struct htable_##name;                                                   \
  39 struct htable_##name##_iter { struct htable_iter i; };                  \
  40 static inline size_t htable_##name##_hash(const void *elem, void *priv) \
  41 {                                                                       \
  42         return hashfn(keyof((const type *)elem));                       \
  43 }                                                                       \
  44 static inline struct htable_##name *htable_##name##_new(void)           \
  45 {                                                                       \
  46         return (struct htable_##name *)htable_new(htable_##name##_hash, \
  47                                                   NULL);                \
  48 }                                                                       \
  49 static inline void htable_##name##_free(const struct htable_##name *ht) \
  50 {                                                                       \
  51         htable_free((const struct htable *)ht);                         \
  52 }                                                                       \
  53 static inline bool htable_##name##_add(struct htable_##name *ht,        \
  54                                        const type *elem)                \
  55 {                                                                       \
  56         return htable_add((struct htable *)ht, hashfn(keyof(elem)), elem); \
  57 }                                                                       \
  58 static inline bool htable_##name##_del(const struct htable_##name *ht,  \
  59                                        const type *elem)                \
  60 {                                                                       \
  61         return htable_del((struct htable *)ht, hashfn(keyof(elem)), elem); \
  62 }                                                                       \
  63 static inline type *htable_##name##_get(const struct htable_##name *ht, \
  64                                         const HTABLE_KTYPE(keyof) k)    \
  65 {                                                                       \
  66         /* Typecheck for cmpfn */                                       \
  67         (void)sizeof(cmpfn((const type *)NULL,                          \
  68                            keyof((const type *)NULL)));                 \
  69         return (type *)htable_get((const struct htable *)ht,            \
  70                                   hashfn(k),                            \
  71                                   (bool (*)(const void *, void *))(cmpfn), \
  72                                   k);                                   \
  73 }                                                                       \
  74 static inline bool htable_##name##_delkey(struct htable_##name *ht,     \
  75                                           const HTABLE_KTYPE(keyof) k) \
  76 {                                                                       \
  77         type *elem = htable_##name##_get(ht, k);                        \
  78         if (elem)                                                       \
  79                 return htable_##name##_del(ht, elem);                   \
  80         return false;                                                   \
  81 }                                                                       \
  82 static inline type *htable_##name##_first(const struct htable_##name *ht, \
  83                                           struct htable_##name##_iter *iter) \
  84 {                                                                       \
  85         return htable_first((const struct htable *)ht, &iter->i);       \
  86 }                                                                       \
  87 static inline type *htable_##name##_next(const struct htable_##name *ht, \
  88                                          struct htable_##name##_iter *iter) \
  89 {                                                                       \
  90         return htable_next((const struct htable *)ht, &iter->i);        \
  91 }
  92
  93 #if HAVE_TYPEOF
  94 #define HTABLE_KTYPE(keyof) typeof(keyof(NULL))
  95 #else
  96 #define HTABLE_KTYPE(keyof) void *
  97 #endif
  98 #endif /* CCAN_HTABLE_TYPE_H */