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Diffstat (limited to 'src/basic/hash-funcs.h')
| -rw-r--r-- | src/basic/hash-funcs.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/src/basic/hash-funcs.h b/src/basic/hash-funcs.h new file mode 100644 index 0000000..3d2ae4b --- /dev/null +++ b/src/basic/hash-funcs.h @@ -0,0 +1,106 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +#include "alloc-util.h" +#include "macro.h" +#include "siphash24.h" + +typedef void (*hash_func_t)(const void *p, struct siphash *state); +typedef int (*compare_func_t)(const void *a, const void *b); + +struct hash_ops { + hash_func_t hash; + compare_func_t compare; + free_func_t free_key; + free_func_t free_value; +}; + +#define _DEFINE_HASH_OPS(uq, name, type, hash_func, compare_func, free_key_func, free_value_func, scope) \ + _unused_ static void (* UNIQ_T(static_hash_wrapper, uq))(const type *, struct siphash *) = hash_func; \ + _unused_ static int (* UNIQ_T(static_compare_wrapper, uq))(const type *, const type *) = compare_func; \ + scope const struct hash_ops name = { \ + .hash = (hash_func_t) hash_func, \ + .compare = (compare_func_t) compare_func, \ + .free_key = free_key_func, \ + .free_value = free_value_func, \ + } + +#define _DEFINE_FREE_FUNC(uq, type, wrapper_name, func) \ + /* Type-safe free function */ \ + static void UNIQ_T(wrapper_name, uq)(void *a) { \ + type *_a = a; \ + func(_a); \ + } + +#define _DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(uq, name, type, hash_func, compare_func, free_func, scope) \ + _DEFINE_FREE_FUNC(uq, type, static_free_wrapper, free_func); \ + _DEFINE_HASH_OPS(uq, name, type, hash_func, compare_func, \ + UNIQ_T(static_free_wrapper, uq), NULL, scope) + +#define _DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(uq, name, type, hash_func, compare_func, type_value, free_func, scope) \ + _DEFINE_FREE_FUNC(uq, type_value, static_free_wrapper, free_func); \ + _DEFINE_HASH_OPS(uq, name, type, hash_func, compare_func, \ + NULL, UNIQ_T(static_free_wrapper, uq), scope) + +#define _DEFINE_HASH_OPS_FULL(uq, name, type, hash_func, compare_func, free_key_func, type_value, free_value_func, scope) \ + _DEFINE_FREE_FUNC(uq, type, static_free_key_wrapper, free_key_func); \ + _DEFINE_FREE_FUNC(uq, type_value, static_free_value_wrapper, free_value_func); \ + _DEFINE_HASH_OPS(uq, name, type, hash_func, compare_func, \ + UNIQ_T(static_free_key_wrapper, uq), \ + UNIQ_T(static_free_value_wrapper, uq), scope) + +#define DEFINE_HASH_OPS(name, type, hash_func, compare_func) \ + _DEFINE_HASH_OPS(UNIQ, name, type, hash_func, compare_func, NULL, NULL,) + +#define DEFINE_PRIVATE_HASH_OPS(name, type, hash_func, compare_func) \ + _DEFINE_HASH_OPS(UNIQ, name, type, hash_func, compare_func, NULL, NULL, static) + +#define DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(name, type, hash_func, compare_func, free_func) \ + _DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(UNIQ, name, type, hash_func, compare_func, free_func,) + +#define DEFINE_PRIVATE_HASH_OPS_WITH_KEY_DESTRUCTOR(name, type, hash_func, compare_func, free_func) \ + _DEFINE_HASH_OPS_WITH_KEY_DESTRUCTOR(UNIQ, name, type, hash_func, compare_func, free_func, static) + +#define DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(name, type, hash_func, compare_func, value_type, free_func) \ + _DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(UNIQ, name, type, hash_func, compare_func, value_type, free_func,) + +#define DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(name, type, hash_func, compare_func, value_type, free_func) \ + _DEFINE_HASH_OPS_WITH_VALUE_DESTRUCTOR(UNIQ, name, type, hash_func, compare_func, value_type, free_func, static) + +#define DEFINE_HASH_OPS_FULL(name, type, hash_func, compare_func, free_key_func, value_type, free_value_func) \ + _DEFINE_HASH_OPS_FULL(UNIQ, name, type, hash_func, compare_func, free_key_func, value_type, free_value_func,) + +#define DEFINE_PRIVATE_HASH_OPS_FULL(name, type, hash_func, compare_func, free_key_func, value_type, free_value_func) \ + _DEFINE_HASH_OPS_FULL(UNIQ, name, type, hash_func, compare_func, free_key_func, value_type, free_value_func, static) + +void string_hash_func(const char *p, struct siphash *state); +#define string_compare_func strcmp +extern const struct hash_ops string_hash_ops; + +void path_hash_func(const char *p, struct siphash *state); +int path_compare_func(const char *a, const char *b) _pure_; +extern const struct hash_ops path_hash_ops; + +/* This will compare the passed pointers directly, and will not dereference them. This is hence not useful for strings + * or suchlike. */ +void trivial_hash_func(const void *p, struct siphash *state); +int trivial_compare_func(const void *a, const void *b) _const_; +extern const struct hash_ops trivial_hash_ops; + +/* 32bit values we can always just embed in the pointer itself, but in order to support 32bit archs we need store 64bit + * values indirectly, since they don't fit in a pointer. */ +void uint64_hash_func(const uint64_t *p, struct siphash *state); +int uint64_compare_func(const uint64_t *a, const uint64_t *b) _pure_; +extern const struct hash_ops uint64_hash_ops; + +/* On some archs dev_t is 32bit, and on others 64bit. And sometimes it's 64bit on 32bit archs, and sometimes 32bit on + * 64bit archs. Yuck! */ +#if SIZEOF_DEV_T != 8 +void devt_hash_func(const dev_t *p, struct siphash *state) _pure_; +int devt_compare_func(const dev_t *a, const dev_t *b) _pure_; +extern const struct hash_ops devt_hash_ops; +#else +#define devt_hash_func uint64_hash_func +#define devt_compare_func uint64_compare_func +#define devt_hash_ops uint64_hash_ops +#endif |