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

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