[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]
[or-cvs] Replace balanced trees with hash tables: this should make s...
Update of /home/or/cvsroot/tor/src/common
In directory moria:/tmp/cvs-serv5279/src/common
Modified Files:
Makefile.am container.c container.h
Added Files:
ht.h
Log Message:
Replace balanced trees with hash tables: this should make stuff significantly faster.
Index: Makefile.am
===================================================================
RCS file: /home/or/cvsroot/tor/src/common/Makefile.am,v
retrieving revision 1.21
retrieving revision 1.22
diff -u -d -r1.21 -r1.22
--- Makefile.am 12 Jan 2005 06:42:31 -0000 1.21
+++ Makefile.am 23 Nov 2005 04:18:45 -0000 1.22
@@ -6,4 +6,4 @@
libor_a_SOURCES = log.c util.c compat.c container.c
libor_crypto_a_SOURCES = crypto.c aes.c tortls.c torgzip.c
-noinst_HEADERS = log.h crypto.h test.h util.h compat.h aes.h torint.h tortls.h strlcpy.c strlcat.c torgzip.h container.h
+noinst_HEADERS = log.h crypto.h test.h util.h compat.h aes.h torint.h tortls.h strlcpy.c strlcat.c torgzip.h container.h ht.h
Index: container.c
===================================================================
RCS file: /home/or/cvsroot/tor/src/common/container.c,v
retrieving revision 1.47
retrieving revision 1.48
diff -u -d -r1.47 -r1.48
--- container.c 1 Nov 2005 03:47:55 -0000 1.47
+++ container.c 23 Nov 2005 04:18:45 -0000 1.48
@@ -14,7 +14,6 @@
#include "compat.h"
#include "util.h"
#include "log.h"
-#include "../or/tree.h"
#include "container.h"
#include "crypto.h"
@@ -25,6 +24,8 @@
#include <string.h>
#include <assert.h>
+#include "ht.h"
+
/* All newly allocated smartlists have this capacity.
*/
#define SMARTLIST_DEFAULT_CAPACITY 32
@@ -445,40 +446,53 @@
#define DEFINE_MAP_STRUCTS(maptype, keydecl, prefix) \
typedef struct prefix ## entry_t { \
- SPLAY_ENTRY(prefix ## entry_t) node; \
+ HT_ENTRY(prefix ## entry_t) node; \
keydecl; \
void *val; \
} prefix ## entry_t; \
struct maptype { \
- SPLAY_HEAD(prefix ## tree, prefix ## entry_t) head; \
+ HT_HEAD(prefix ## tree, prefix ## entry_t) head; \
};
DEFINE_MAP_STRUCTS(strmap_t, char *key, strmap_);
DEFINE_MAP_STRUCTS(digestmap_t, char key[DIGEST_LEN], digestmap_);
/** Helper: compare strmap_t_entry objects by key value. */
-static int
-compare_strmap_entries(strmap_entry_t *a,
- strmap_entry_t *b)
+static INLINE int
+strmap_entries_eq(strmap_entry_t *a, strmap_entry_t *b)
{
- return strcmp(a->key, b->key);
+ return !strcmp(a->key, b->key);
+}
+
+static INLINE unsigned int
+strmap_entry_hash(strmap_entry_t *a)
+{
+ return ht_string_hash(a->key);
}
/** Helper: compare digestmap_entry_t objects by key value. */
-static int
-compare_digestmap_entries(digestmap_entry_t *a,
- digestmap_entry_t *b)
+static INLINE int
+digestmap_entries_eq(digestmap_entry_t *a, digestmap_entry_t *b)
{
- return memcmp(a->key, b->key, DIGEST_LEN);
+ return !memcmp(a->key, b->key, DIGEST_LEN);
}
-SPLAY_PROTOTYPE(strmap_tree, strmap_entry_t, node, compare_strmap_entries);
-SPLAY_GENERATE(strmap_tree, strmap_entry_t, node, compare_strmap_entries);
+static INLINE unsigned int
+digestmap_entry_hash(digestmap_entry_t *a)
+{
+ uint32_t *p = (uint32_t*)a->key;
+ return ht_improve_hash(p[0] ^ p[1] ^ p[2] ^ p[3] ^ p[4]);
+}
-SPLAY_PROTOTYPE(digestmap_tree, digestmap_entry_t, node,
- compare_digestmap_entries);
-SPLAY_GENERATE(digestmap_tree, digestmap_entry_t, node,
- compare_digestmap_entries);
+HT_PROTOTYPE(strmap_tree, strmap_entry_t, node, strmap_entry_hash,
+ strmap_entries_eq);
+HT_GENERATE(strmap_tree, strmap_entry_t, node, strmap_entry_hash,
+ strmap_entries_eq, 0.6, malloc, realloc, free);
+
+HT_PROTOTYPE(digestmap_tree, digestmap_entry_t, node, digestmap_entry_hash,
+ digestmap_entries_eq);
+HT_GENERATE(digestmap_tree, digestmap_entry_t, node, digestmap_entry_hash,
+ digestmap_entries_eq, 0.6, malloc, realloc, free);
/** Constructor to create a new empty map from strings to void*'s.
*/
@@ -487,7 +501,7 @@
{
strmap_t *result;
result = tor_malloc(sizeof(strmap_t));
- SPLAY_INIT(&result->head);
+ HT_INIT(&result->head);
return result;
}
@@ -498,7 +512,7 @@
{
digestmap_t *result;
result = tor_malloc(sizeof(digestmap_t));
- SPLAY_INIT(&result->head);
+ HT_INIT(&result->head);
return result;
}
@@ -518,7 +532,7 @@
tor_assert(key);
tor_assert(val);
search.key = (char*)key;
- resolve = SPLAY_FIND(strmap_tree, &map->head, &search);
+ resolve = HT_FIND(strmap_tree, &map->head, &search);
if (resolve) {
oldval = resolve->val;
resolve->val = val;
@@ -527,7 +541,8 @@
resolve = tor_malloc_zero(sizeof(strmap_entry_t));
resolve->key = tor_strdup(key);
resolve->val = val;
- SPLAY_INSERT(strmap_tree, &map->head, resolve);
+ tor_assert(!HT_FIND(strmap_tree, &map->head, resolve));
+ HT_INSERT(strmap_tree, &map->head, resolve);
return NULL;
}
}
@@ -543,7 +558,7 @@
tor_assert(key);
tor_assert(val);
memcpy(&search.key, key, DIGEST_LEN);
- resolve = SPLAY_FIND(digestmap_tree, &map->head, &search);
+ resolve = HT_FIND(digestmap_tree, &map->head, &search);
if (resolve) {
oldval = resolve->val;
resolve->val = val;
@@ -552,7 +567,7 @@
resolve = tor_malloc_zero(sizeof(digestmap_entry_t));
memcpy(resolve->key, key, DIGEST_LEN);
resolve->val = val;
- SPLAY_INSERT(digestmap_tree, &map->head, resolve);
+ HT_INSERT(digestmap_tree, &map->head, resolve);
return NULL;
}
}
@@ -568,7 +583,7 @@
tor_assert(map);
tor_assert(key);
search.key = (char*)key;
- resolve = SPLAY_FIND(strmap_tree, &map->head, &search);
+ resolve = HT_FIND(strmap_tree, &map->head, &search);
if (resolve) {
return resolve->val;
} else {
@@ -585,7 +600,7 @@
tor_assert(map);
tor_assert(key);
memcpy(&search.key, key, DIGEST_LEN);
- resolve = SPLAY_FIND(digestmap_tree, &map->head, &search);
+ resolve = HT_FIND(digestmap_tree, &map->head, &search);
if (resolve) {
return resolve->val;
} else {
@@ -608,10 +623,9 @@
tor_assert(map);
tor_assert(key);
search.key = (char*)key;
- resolve = SPLAY_FIND(strmap_tree, &map->head, &search);
+ resolve = HT_REMOVE(strmap_tree, &map->head, &search);
if (resolve) {
oldval = resolve->val;
- SPLAY_REMOVE(strmap_tree, &map->head, resolve);
tor_free(resolve->key);
tor_free(resolve);
return oldval;
@@ -630,10 +644,9 @@
tor_assert(map);
tor_assert(key);
memcpy(&search.key, key, DIGEST_LEN);
- resolve = SPLAY_FIND(digestmap_tree, &map->head, &search);
+ resolve = HT_REMOVE(digestmap_tree, &map->head, &search);
if (resolve) {
oldval = resolve->val;
- SPLAY_REMOVE(digestmap_tree, &map->head, resolve);
tor_free(resolve);
return oldval;
} else {
@@ -679,53 +692,6 @@
return v;
}
-/** Invoke fn() on every entry of the map, in order. For every entry,
- * fn() is invoked with that entry's key, that entry's value, and the
- * value of <b>data</b> supplied to strmap_foreach. fn() must return a new
- * (possibly unmodified) value for each entry: if fn() returns NULL, the
- * entry is removed.
- *
- * Example:
- * \code
- * static void* upcase_and_remove_empty_vals(const char *key, void *val,
- * void* data) {
- * char *cp = (char*)val;
- * if (!*cp) { // val is an empty string.
- * free(val);
- * return NULL;
- * } else {
- * for (; *cp; cp++)
- * *cp = toupper(*cp);
- * }
- * return val;
- * }
- * }
- *
- * ...
- *
- * strmap_foreach(map, upcase_and_remove_empty_vals, NULL);
- * \endcode
- */
-void
-strmap_foreach(strmap_t *map,
- void* (*fn)(const char *key, void *val, void *data),
- void *data)
-{
- strmap_entry_t *ptr, *next;
- tor_assert(map);
- tor_assert(fn);
- for (ptr = SPLAY_MIN(strmap_tree, &map->head); ptr != NULL; ptr = next) {
- /* This remove-in-place usage is specifically blessed in tree(3). */
- next = SPLAY_NEXT(strmap_tree, &map->head, ptr);
- ptr->val = fn(ptr->key, ptr->val, data);
- if (!ptr->val) {
- SPLAY_REMOVE(strmap_tree, &map->head, ptr);
- tor_free(ptr->key);
- tor_free(ptr);
- }
- }
-}
-
/** return an <b>iterator</b> pointer to the front of a map.
*
* Iterator example:
@@ -756,14 +722,14 @@
strmap_iter_init(strmap_t *map)
{
tor_assert(map);
- return SPLAY_MIN(strmap_tree, &map->head);
+ return HT_START(strmap_tree, &map->head);
}
digestmap_iter_t *
digestmap_iter_init(digestmap_t *map)
{
tor_assert(map);
- return SPLAY_MIN(digestmap_tree, &map->head);
+ return HT_START(digestmap_tree, &map->head);
}
/** Advance the iterator <b>iter</b> for map a single step to the next entry.
@@ -773,7 +739,7 @@
{
tor_assert(map);
tor_assert(iter);
- return SPLAY_NEXT(strmap_tree, &map->head, iter);
+ return HT_NEXT(strmap_tree, &map->head, iter);
}
digestmap_iter_t *
@@ -781,7 +747,7 @@
{
tor_assert(map);
tor_assert(iter);
- return SPLAY_NEXT(digestmap_tree, &map->head, iter);
+ return HT_NEXT(digestmap_tree, &map->head, iter);
}
/** Advance the iterator <b>iter</b> a single step to the next entry, removing
@@ -793,10 +759,9 @@
strmap_iter_t *next;
tor_assert(map);
tor_assert(iter);
- next = SPLAY_NEXT(strmap_tree, &map->head, iter);
- SPLAY_REMOVE(strmap_tree, &map->head, iter);
- tor_free(iter->key);
- tor_free(iter);
+ next = HT_NEXT_RMV(strmap_tree, &map->head, iter);
+ tor_free((*iter)->key);
+ tor_free(*iter);
return next;
}
@@ -806,9 +771,8 @@
digestmap_iter_t *next;
tor_assert(map);
tor_assert(iter);
- next = SPLAY_NEXT(digestmap_tree, &map->head, iter);
- SPLAY_REMOVE(digestmap_tree, &map->head, iter);
- tor_free(iter);
+ next = HT_NEXT_RMV(digestmap_tree, &map->head, iter);
+ tor_free(*iter);
return next;
}
@@ -820,8 +784,8 @@
tor_assert(iter);
tor_assert(keyp);
tor_assert(valp);
- *keyp = iter->key;
- *valp = iter->val;
+ *keyp = (*iter)->key;
+ *valp = (*iter)->val;
}
void
@@ -830,8 +794,8 @@
tor_assert(iter);
tor_assert(keyp);
tor_assert(valp);
- *keyp = iter->key;
- *valp = iter->val;
+ *keyp = (*iter)->key;
+ *valp = (*iter)->val;
}
/** Return true iff iter has advanced past the last entry of map.
@@ -853,30 +817,32 @@
void
strmap_free(strmap_t *map, void (*free_val)(void*))
{
- strmap_entry_t *ent, *next;
- for (ent = SPLAY_MIN(strmap_tree, &map->head); ent != NULL; ent = next) {
- next = SPLAY_NEXT(strmap_tree, &map->head, ent);
- SPLAY_REMOVE(strmap_tree, &map->head, ent);
- tor_free(ent->key);
+ strmap_entry_t **ent, **next, *this;
+ for (ent = HT_START(strmap_tree, &map->head); ent != NULL; ent = next) {
+ this = *ent;
+ next = HT_NEXT_RMV(strmap_tree, &map->head, ent);
+ tor_free(this->key);
if (free_val)
- free_val(ent->val);
- tor_free(ent);
+ free_val(this->val);
+ tor_free(this);
}
- tor_assert(SPLAY_EMPTY(&map->head));
+ tor_assert(HT_EMPTY(&map->head));
+ HT_CLEAR(strmap_tree, &map->head);
tor_free(map);
}
void
digestmap_free(digestmap_t *map, void (*free_val)(void*))
{
- digestmap_entry_t *ent, *next;
- for (ent = SPLAY_MIN(digestmap_tree, &map->head); ent != NULL; ent = next) {
- next = SPLAY_NEXT(digestmap_tree, &map->head, ent);
- SPLAY_REMOVE(digestmap_tree, &map->head, ent);
+ digestmap_entry_t **ent, **next, *this;
+ for (ent = HT_START(digestmap_tree, &map->head); ent != NULL; ent = next) {
+ this = *ent;
+ next = HT_NEXT_RMV(digestmap_tree, &map->head, ent);
if (free_val)
- free_val(ent->val);
- tor_free(ent);
+ free_val(this->val);
+ tor_free(this);
}
- tor_assert(SPLAY_EMPTY(&map->head));
+ tor_assert(HT_EMPTY(&map->head));
+ HT_CLEAR(digestmap_tree, &map->head);
tor_free(map);
}
@@ -884,12 +850,12 @@
int
strmap_isempty(strmap_t *map)
{
- return SPLAY_EMPTY(&map->head);
+ return HT_EMPTY(&map->head);
}
int
digestmap_isempty(digestmap_t *map)
{
- return SPLAY_EMPTY(&map->head);
+ return HT_EMPTY(&map->head);
}
Index: container.h
===================================================================
RCS file: /home/or/cvsroot/tor/src/common/container.h,v
retrieving revision 1.23
retrieving revision 1.24
diff -u -d -r1.23 -r1.24
--- container.h 1 Nov 2005 03:47:55 -0000 1.23
+++ container.h 23 Nov 2005 04:18:45 -0000 1.24
@@ -110,13 +110,11 @@
#define DECLARE_MAP_FNS(maptype, keytype, prefix) \
typedef struct maptype maptype; \
- typedef struct prefix##entry_t prefix##iter_t; \
+ typedef struct prefix##entry_t *prefix##iter_t; \
maptype* prefix##new(void); \
void* prefix##set(maptype *map, keytype key, void *val); \
void* prefix##get(maptype *map, keytype key); \
void* prefix##remove(maptype *map, keytype key); \
- typedef void* (*prefix##foreach_fn)(keytype key, void *val, void *data); \
- void prefix##foreach(maptype *map, prefix##foreach_fn fn, void *data); \
void prefix##free(maptype *map, void (*free_val)(void*)); \
int prefix##isempty(maptype *map); \
prefix##iter_t *prefix##iter_init(maptype *map); \
--- NEW FILE: ht.h ---
/* Copyright 2002 Christopher Clark */
/* Copyright 2005 Nick Mathewson */
/* See license at end. */
/* $Id: ht.h,v 1.1 2005/11/23 04:18:45 nickm Exp $ */
/* Based on ideas by Christopher Clark and interfaces from Niels Provos. */
#ifndef __HT_H
#define __HT_H
#define HT_H_ID "$Id: ht.h,v 1.1 2005/11/23 04:18:45 nickm Exp $"
#define HT_HEAD(name, type) \
struct name { \
/* How long is the hash table? */ \
unsigned hth_table_length; \
/* The hash table itself. */ \
struct type **hth_table; \
/* How many elements does the table contain? */ \
unsigned hth_n_entries; \
/* How many elements will we allow in the table before resizing it? */ \
unsigned hth_load_limit; \
/* Position of hth_table_length in the primes table. */ \
int hth_prime_idx; \
}
#define HT_INITIALIZER() \
{ 0, NULL, 0, 0, -1 }
#define HT_INIT(root) do { \
(root)->hth_table_length = 0; \
(root)->hth_table = NULL; \
(root)->hth_n_entries = 0; \
(root)->hth_load_limit = 0; \
(root)->hth_prime_idx = -1; \
} while (0)
#define HT_ENTRY(type) \
struct { \
struct type *hte_next; \
unsigned hte_hash; \
}
#define HT_EMPTY(head) \
((head)->hth_n_entries == 0)
/* Helper: alias for the bucket containing 'elm'. */
#define _HT_BUCKET(head, field, elm) \
((head)->hth_table[elm->field.hte_hash % head->hth_table_length])
/* How many elements in 'head'? */
#define HT_SIZE(head) \
((head)->hth_n_entries)
#define HT_FIND(name, head, elm) name##_HT_FIND((head), (elm))
#define HT_INSERT(name, head, elm) name##_HT_INSERT((head), (elm))
#define HT_REPLACE(name, head, elm) name##_HT_REPLACE((head), (elm))
#define HT_REMOVE(name, head, elm) name##_HT_REMOVE((head), (elm))
#define HT_START(name, head) name##_HT_START(head)
#define HT_NEXT(name, head, elm) name##_HT_NEXT((head), (elm))
#define HT_NEXT_RMV(name, head, elm) name##_HT_NEXT_RMV((head), (elm))
#define HT_CLEAR(name, head) name##_HT_CLEAR(head)
/* Helper: */
static __inline unsigned
ht_improve_hash(unsigned h)
{
/* Aim to protect against poor hash functions by adding logic here
* - logic taken from java 1.4 hashtable source */
h += ~(h << 9);
h ^= ((h >> 14) | (h << 18)); /* >>> */
h += (h << 4);
h ^= ((h >> 10) | (h << 22)); /* >>> */
return h;
}
/** Basic string hash function, from Java standard String.hashCode(). */
static __inline unsigned
ht_string_hash(const char *s)
{
unsigned h = 0;
int m = 1;
while (*s) {
h += ((signed char)*s++)*m;
m = (m<<5)-1; /* m *= 31 */
}
return h;
}
#define _HT_SET_HASH(elm, field, hashfn) \
do { \
elm->field.hte_next = NULL; \
elm->field.hte_hash = hashfn(elm); \
} while (0)
#define HT_FOREACH(x, name, head) \
for ((x) = HT_START(name, head); \
(x) != NULL; \
(x) = HT_NEXT(name, head, x))
#define HT_PROTOTYPE(name, type, field, hashfn, eqfn) \
int name##_HT_GROW(struct name *ht, unsigned min_capacity); \
void name##_HT_CLEAR(struct name *ht); \
int _##name##_HT_REP_OK(struct name *ht); \
/* Helper: returns a pointer to the right location in the table \
* 'head' to find or insert the element 'elm'. */ \
static __inline struct type ** \
_##name##_HT_FIND_P(struct name *head, struct type *elm) \
{ \
struct type **p; \
if (!head->hth_table) \
return NULL; \
p = &_HT_BUCKET(head, field, elm); \
while (*p) { \
if (eqfn(*p, elm)) \
return p; \
p = &(*p)->field.hte_next; \
} \
return p; \
} \
/* Return a pointer to the element in the table 'head' matching 'elm', \
* or NULL if no such element exists */ \
static __inline struct type * \
name##_HT_FIND(struct name *head, struct type *elm) \
{ \
struct type **p; \
_HT_SET_HASH(elm, field, hashfn); \
p = _##name##_HT_FIND_P(head, elm); \
return p ? *p : NULL; \
} \
/* Insert the element 'elm' into the table 'head'. Do not call this \
* function if the table might already contain a matching element. */ \
static __inline void \
name##_HT_INSERT(struct name *head, struct type *elm) \
{ \
struct type **p; \
if (!head->hth_table || head->hth_n_entries >= head->hth_load_limit) \
name##_HT_GROW(head, head->hth_n_entries+1); \
++head->hth_n_entries; \
_HT_SET_HASH(elm, field, hashfn); \
p = &_HT_BUCKET(head, field, elm); \
elm->field.hte_next = *p; \
*p = elm; \
} \
/* Insert the element 'elm' into the table 'head'. If there already \
* a matching element in the table, replace that element and return \
* it. */ \
static __inline struct type * \
name##_HT_REPLACE(struct name *head, struct type *elm) \
{ \
struct type **p, *r; \
if (!head->hth_table || head->hth_n_entries >= head->hth_load_limit) \
name##_HT_GROW(head, head->hth_n_entries+1); \
_HT_SET_HASH(elm, field, hashfn); \
p = _##name##_HT_FIND_P(head, elm); \
r = *p; \
*p = elm; \
if (r && (r!=elm)) { \
elm->field.hte_next = r->field.hte_next; \
r->field.hte_next = NULL; \
return r; \
} else { \
++head->hth_n_entries; \
return NULL; \
} \
} \
/* Remove any element matching 'elm' from the table 'head'. If such \
* an element is found, return it; otherwise return NULL. */ \
static __inline struct type * \
name##_HT_REMOVE(struct name *head, struct type *elm) \
{ \
struct type **p, *r; \
_HT_SET_HASH(elm, field, hashfn); \
p = _##name##_HT_FIND_P(head,elm); \
if (!p || !*p) \
return NULL; \
r = *p; \
*p = r->field.hte_next; \
r->field.hte_next = NULL; \
--head->hth_n_entries; \
return r; \
} \
/* Invoke the function 'fn' on every element of the table 'head', \
* using 'data' as its second argument. If the function returns \
* nonzero, remove the most recently examined element before invoking \
* the function again. */ \
static __inline void \
name##_HT_FOREACH_FN(struct name *head, \
int (*fn)(struct type *, void *), \
void *data) \
{ \
/* XXXX use tricks to prevent concurrent mod? */ \
unsigned idx; \
int remove; \
struct type **p, **nextp, *next; \
if (!head->hth_table) \
return; \
for (idx=0; idx < head->hth_table_length; ++idx) { \
p = &head->hth_table[idx]; \
while (*p) { \
nextp = &(*p)->field.hte_next; \
next = *nextp; \
remove = fn(*p, data); \
if (remove) { \
--head->hth_n_entries; \
*p = next; \
} else { \
p = nextp; \
} \
} \
} \
} \
/* Return a pointer to the first element in the table 'head', under \
* an arbitrary order. This order is stable under remove operations, \
* but not under others. If the table is empty, return NULL. */ \
static __inline struct type ** \
name##_HT_START(struct name *head) \
{ \
unsigned b = 0; \
while (b < head->hth_table_length) { \
if (head->hth_table[b]) \
return &head->hth_table[b]; \
++b; \
} \
return NULL; \
} \
/* Return the next element in 'head' after 'elm', under the arbitrary \
* order used by HT_START. If there are no more elements, return \
* NULL. If 'elm' is to be removed from the table, you must call \
* this function for the next value before you remove it. \
*/ \
static __inline struct type ** \
name##_HT_NEXT(struct name *head, struct type **elm) \
{ \
if ((*elm)->field.hte_next) { \
return &(*elm)->field.hte_next; \
} else { \
unsigned b = ((*elm)->field.hte_hash % head->hth_table_length)+1; \
while (b < head->hth_table_length) { \
if (head->hth_table[b]) \
return &head->hth_table[b]; \
++b; \
} \
return NULL; \
} \
} \
static __inline struct type ** \
name##_HT_NEXT_RMV(struct name *head, struct type **elm) \
{ \
unsigned h = (*elm)->field.hte_hash; \
*elm = (*elm)->field.hte_next; \
--head->hth_n_entries; \
if (*elm) { \
return elm; \
} else { \
unsigned b = (h % head->hth_table_length)+1; \
while (b < head->hth_table_length) { \
if (head->hth_table[b]) \
return &head->hth_table[b]; \
++b; \
} \
return NULL; \
} \
}
#if 0
/* Helpers for an iterator type that saves some mod operations at the expense
* of many branches. Not worth it, it seems. */
#define HT_ITER(type) \
struct type##_ITER { \
struct type **hti_nextp; \
unsigned hti_bucket; \
}
static __inline void \
name##_HT_ITER_START(struct name *head, struct type##_ITER *iter) \
{ \
/* XXXX Magic to stop modifications? */ \
iter->hti_bucket = 0; \
while (iter->hti_bucket < head->hth_table_length) { \
iter->hti_nextp = &head->hth_table[iter->hti_bucket]; \
if (*iter->hti_nextp) \
return; \
++iter->hti_bucket; \
} \
iter->hti_nextp = NULL; \
} \
static __inline int \
name##_HT_ITER_DONE(struct name *head, struct type##_ITER *iter) \
{ \
return iter->hti_nextp == NULL; \
} \
static __inline struct type * \
name##_HT_ITER_GET(struct name *head, struct type##_ITER *iter) \
{ \
return *iter->hti_nextp; \
} \
static __inline void \
name##_HT_ITER_NEXT(struct name *head, struct type##_ITER *iter) \
{ \
if (!iter->hti_nextp) \
return; \
if ((*iter->hti_nextp)->field.hte_next) { \
iter->hti_nextp = &(*iter->hti_nextp)->field.hte_next; \
return; \
} \
while (++iter->hti_bucket < head->hth_table_length) { \
iter->hti_nextp = &head->hth_table[iter->hti_bucket]; \
if (*iter->hti_nextp) \
return; \
++iter->hti_bucket; \
} \
iter->hti_nextp = NULL; \
} \
static __inline void \
name##_HT_ITER_NEXT_RMV(struct name *head, struct type##_ITER *iter) \
{ \
if (!iter->hti_nextp) \
return; \
--head->hth_n_entries; \
if ((*iter->hti_nextp)->field.hte_next) { \
*iter->hti_nextp = (*iter->hti_nextp)->field.hte_next; \
if (*iter->hti_nextp) \
return; \
} \
while (++iter->hti_bucket < head->hth_table_length) { \
iter->hti_nextp = &head->hth_table[iter->hti_bucket]; \
if (*iter->hti_nextp) \
return; \
++iter->hti_bucket; \
} \
iter->hti_nextp = NULL; \
}
#endif
#define HT_GENERATE(name, type, field, hashfn, eqfn, load, mallocfn, reallocfn, freefn) \
static unsigned name##_PRIMES[] = { \
53, 97, 193, 389, \
769, 1543, 3079, 6151, \
12289, 24593, 49157, 98317, \
196613, 393241, 786433, 1572869, \
3145739, 6291469, 12582917, 25165843, \
50331653, 100663319, 201326611, 402653189, \
805306457, 1610612741 \
}; \
static unsigned name##_N_PRIMES = \
sizeof(name##_PRIMES)/sizeof(name##_PRIMES[0]); \
/* Expand the internal table of 'head' until it is large enough to \
* hold 'size' elements. Return 0 on success, -1 on allocation \
* failure. */ \
int \
name##_HT_GROW(struct name *head, unsigned size) \
{ \
unsigned new_len, new_load_limit; \
int prime_idx; \
struct type **new_table; \
if (head->hth_prime_idx == (int)name##_N_PRIMES - 1) \
return 0; \
if (head->hth_load_limit > size) \
return 0; \
prime_idx = head->hth_prime_idx; \
do { \
new_len = name##_PRIMES[++prime_idx]; \
new_load_limit = (unsigned)(load*new_len); \
} while (new_load_limit <= size && \
prime_idx < (int)name##_N_PRIMES); \
if ((new_table = mallocfn(new_len*sizeof(struct type*)))) { \
unsigned b; \
memset(new_table, 0, new_len*sizeof(struct type*)); \
for (b = 0; b < head->hth_table_length; ++b) { \
struct type *elm, *next; \
unsigned b2; \
elm = head->hth_table[b]; \
while (elm) { \
next = elm->field.hte_next; \
b2 = elm->field.hte_hash % new_len; \
elm->field.hte_next = new_table[b2]; \
new_table[b2] = elm; \
elm = next; \
} \
} \
freefn(head->hth_table); \
head->hth_table = new_table; \
} else { \
unsigned b, b2; \
new_table = reallocfn(head->hth_table, new_len*sizeof(struct type*)); \
if (!new_table) return -1; \
memset(new_table + head->hth_table_length, 0, \
(new_len - head->hth_table_length)*sizeof(struct type*)); \
for (b=0; b < head->hth_table_length; ++b) { \
struct type *e, **pE; \
for (pE = &new_table[b], e = *pE; e != NULL; e = *pE) { \
b2 = e->field.hte_hash % new_len; \
if (b2 == b) { \
pE = &e->field.hte_next; \
} else { \
*pE = e->field.hte_next; \
e->field.hte_next = new_table[b2]; \
new_table[b2] = e; \
} \
} \
} \
head->hth_table = new_table; \
} \
head->hth_table_length = new_len; \
head->hth_prime_idx = prime_idx; \
head->hth_load_limit = new_load_limit; \
return 0; \
} \
/* Free all storage held by 'head'. Does not free 'head' itself, or \
* individual elements. */ \
void \
name##_HT_CLEAR(struct name *head) \
{ \
if (head->hth_table) \
freefn(head->hth_table); \
head->hth_table_length = 0; \
HT_INIT(head); \
} \
/* Debugging helper: return true iff the representation of 'head' is \
* internally consistent. */ \
int \
_##name##_HT_REP_OK(struct name *head) \
{ \
unsigned n, i; \
struct type *elm; \
if (!head->hth_table_length) { \
return !head->hth_table && !head->hth_n_entries && \
!head->hth_load_limit && head->hth_prime_idx == -1; \
} \
if (!head->hth_table || head->hth_prime_idx < 0 || \
!head->hth_load_limit) \
return 0; \
if (head->hth_n_entries > head->hth_load_limit) \
return 0; \
if (head->hth_table_length != name##_PRIMES[head->hth_prime_idx]) \
return 0; \
if (head->hth_load_limit != (unsigned)(load*head->hth_table_length)) \
return 0; \
for (n = i = 0; i < head->hth_table_length; ++i) { \
for (elm = head->hth_table[i]; elm; elm = elm->field.hte_next) { \
if (elm->field.hte_hash != hashfn(elm)) \
return 0; \
if ((elm->field.hte_hash % head->hth_table_length) != i) \
return 0; \
++n; \
} \
} \
if (n != head->hth_n_entries) \
return 0; \
return 1; \
}
/*
* Copyright 2005, Nick Mathewson. Implementation logic is adapted from code
* by Cristopher Clark, retrofit to allow drop-in memory management, and to
* use the same interface as Niels Provos's HT_H. I'm not sure whether this
* is a derived work any more, but whether it is or not, the license below
* applies.
*
* Copyright (c) 2002, Christopher Clark
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* * Neither the name of the original author; nor the names of any contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#endif