st.c
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/* This is a public domain general purpose hash table package written by Peter Moore @ UCB. */
/* static char sccsid[] = "@(#) st.c 5.1 89/12/14 Crucible"; */
#ifdef NOT_RUBY
#include "regint.h"
#include "st.h"
#else
#include "ruby/ruby.h"
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <string.h>
typedef struct st_table_entry st_table_entry;
struct st_table_entry {
st_index_t hash;
st_data_t key;
st_data_t record;
st_table_entry *next;
st_table_entry *fore, *back;
};
#define ST_DEFAULT_MAX_DENSITY 5
#define ST_DEFAULT_INIT_TABLE_SIZE 11
/*
* DEFAULT_MAX_DENSITY is the default for the largest we allow the
* average number of items per bin before increasing the number of
* bins
*
* DEFAULT_INIT_TABLE_SIZE is the default for the number of bins
* allocated initially
*
*/
static const struct st_hash_type type_numhash = {
st_numcmp,
st_numhash,
};
/* extern int strcmp(const char *, const char *); */
static st_index_t strhash(st_data_t);
static const struct st_hash_type type_strhash = {
strcmp,
strhash,
};
static st_index_t strcasehash(st_data_t);
static const struct st_hash_type type_strcasehash = {
st_strcasecmp,
strcasehash,
};
static void rehash(st_table *);
#ifdef RUBY
#define malloc xmalloc
#define calloc xcalloc
#define free(x) xfree(x)
#endif
#define numberof(array) (int)(sizeof(array) / sizeof((array)[0]))
#define alloc(type) (type*)malloc((size_t)sizeof(type))
#define Calloc(n,s) (char*)calloc((n),(s))
#define EQUAL(table,x,y) ((x)==(y) || (*(table)->type->compare)((x),(y)) == 0)
/* remove cast to unsigned int in the future */
#define do_hash(key,table) (unsigned int)(st_index_t)(*(table)->type->hash)((key))
#define do_hash_bin(key,table) (do_hash((key), (table))%(table)->num_bins)
/*
* MINSIZE is the minimum size of a dictionary.
*/
#define MINSIZE 8
/*
Table of prime numbers 2^n+a, 2<=n<=30.
*/
static const unsigned int primes[] = {
8 + 3,
16 + 3,
32 + 5,
64 + 3,
128 + 3,
256 + 27,
512 + 9,
1024 + 9,
2048 + 5,
4096 + 3,
8192 + 27,
16384 + 43,
32768 + 3,
65536 + 45,
131072 + 29,
262144 + 3,
524288 + 21,
1048576 + 7,
2097152 + 17,
4194304 + 15,
8388608 + 9,
16777216 + 43,
33554432 + 35,
67108864 + 15,
134217728 + 29,
268435456 + 3,
536870912 + 11,
1073741824 + 85,
0
};
static st_index_t
new_size(st_index_t size)
{
int i;
#if 0
for (i=3; i<31; i++) {
if ((1<<i) > size) return 1<<i;
}
return -1;
#else
st_index_t newsize;
for (i = 0, newsize = MINSIZE; i < numberof(primes); i++, newsize <<= 1) {
if (newsize > size) return primes[i];
}
/* Ran out of polynomials */
#ifndef NOT_RUBY
rb_raise(rb_eRuntimeError, "st_table too big");
#endif
return -1; /* should raise exception */
#endif
}
#ifdef HASH_LOG
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
static struct {
int all, total, num, str, strcase;
} collision;
static int init_st = 0;
static void
stat_col(void)
{
char fname[10+sizeof(long)*3];
FILE *f = fopen((snprintf(fname, sizeof(fname), "/tmp/col%ld", (long)getpid()), fname), "w");
fprintf(f, "collision: %d / %d (%6.2f)\n", collision.all, collision.total,
((double)collision.all / (collision.total)) * 100);
fprintf(f, "num: %d, str: %d, strcase: %d\n", collision.num, collision.str, collision.strcase);
fclose(f);
}
#endif
#define MAX_PACKED_NUMHASH (ST_DEFAULT_INIT_TABLE_SIZE/2)
st_table*
st_init_table_with_size(const struct st_hash_type *type, st_index_t size)
{
st_table *tbl;
#ifdef HASH_LOG
# if HASH_LOG+0 < 0
{
const char *e = getenv("ST_HASH_LOG");
if (!e || !*e) init_st = 1;
}
# endif
if (init_st == 0) {
init_st = 1;
atexit(stat_col);
}
#endif
size = new_size(size); /* round up to prime number */
tbl = alloc(st_table);
tbl->type = type;
tbl->num_entries = 0;
tbl->entries_packed = type == &type_numhash && size/2 <= MAX_PACKED_NUMHASH;
tbl->num_bins = size;
tbl->bins = (st_table_entry **)Calloc(size, sizeof(st_table_entry*));
tbl->head = 0;
tbl->tail = 0;
return tbl;
}
st_table*
st_init_table(const struct st_hash_type *type)
{
return st_init_table_with_size(type, 0);
}
st_table*
st_init_numtable(void)
{
return st_init_table(&type_numhash);
}
st_table*
st_init_numtable_with_size(st_index_t size)
{
return st_init_table_with_size(&type_numhash, size);
}
st_table*
st_init_strtable(void)
{
return st_init_table(&type_strhash);
}
st_table*
st_init_strtable_with_size(st_index_t size)
{
return st_init_table_with_size(&type_strhash, size);
}
st_table*
st_init_strcasetable(void)
{
return st_init_table(&type_strcasehash);
}
st_table*
st_init_strcasetable_with_size(st_index_t size)
{
return st_init_table_with_size(&type_strcasehash, size);
}
void
st_clear(st_table *table)
{
register st_table_entry *ptr, *next;
st_index_t i;
if (table->entries_packed) {
table->num_entries = 0;
return;
}
for(i = 0; i < table->num_bins; i++) {
ptr = table->bins[i];
table->bins[i] = 0;
while (ptr != 0) {
next = ptr->next;
free(ptr);
ptr = next;
}
}
table->num_entries = 0;
table->head = 0;
table->tail = 0;
}
void
st_free_table(st_table *table)
{
st_clear(table);
free(table->bins);
free(table);
}
size_t
st_memsize(const st_table *table)
{
if (table->entries_packed) {
return table->num_bins * sizeof (void *) + sizeof(st_table);
}
else {
return table->num_entries * sizeof(struct st_table_entry) + table->num_bins * sizeof (void *) + sizeof(st_table);
}
}
#define PTR_NOT_EQUAL(table, ptr, hash_val, key) \
((ptr) != 0 && ((ptr)->hash != (hash_val) || !EQUAL((table), (key), (ptr)->key)))
#ifdef HASH_LOG
static void
count_collision(const struct st_hash_type *type)
{
collision.all++;
if (type == &type_numhash) {
collision.num++;
}
else if (type == &type_strhash) {
collision.strcase++;
}
else if (type == &type_strcasehash) {
collision.str++;
}
}
#define COLLISION (collision_check ? count_collision(table->type) : (void)0)
#define FOUND_ENTRY (collision_check ? collision.total++ : (void)0)
#else
#define COLLISION
#define FOUND_ENTRY
#endif
#define FIND_ENTRY(table, ptr, hash_val, bin_pos) do {\
(bin_pos) = (hash_val)%(table)->num_bins;\
(ptr) = (table)->bins[(bin_pos)];\
FOUND_ENTRY;\
if (PTR_NOT_EQUAL((table), (ptr), (hash_val), key)) {\
COLLISION;\
while (PTR_NOT_EQUAL((table), (ptr)->next, (hash_val), key)) {\
(ptr) = (ptr)->next;\
}\
(ptr) = (ptr)->next;\
}\
} while (0)
#define collision_check 0
int
st_lookup(st_table *table, register st_data_t key, st_data_t *value)
{
st_index_t hash_val, bin_pos;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == key) {
if (value !=0) *value = (st_data_t)table->bins[i*2+1];
return 1;
}
}
return 0;
}
hash_val = do_hash(key, table);
FIND_ENTRY(table, ptr, hash_val, bin_pos);
if (ptr == 0) {
return 0;
}
else {
if (value != 0) *value = ptr->record;
return 1;
}
}
int
st_get_key(st_table *table, register st_data_t key, st_data_t *result)
{
st_index_t hash_val, bin_pos;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == key) {
if (result !=0) *result = (st_data_t)table->bins[i*2];
return 1;
}
}
return 0;
}
hash_val = do_hash(key, table);
FIND_ENTRY(table, ptr, hash_val, bin_pos);
if (ptr == 0) {
return 0;
}
else {
if (result != 0) *result = ptr->key;
return 1;
}
}
#undef collision_check
#define collision_check 1
#define MORE_PACKABLE_P(table) \
((st_index_t)((table)->num_entries+1) * 2 <= (table)->num_bins && \
(table)->num_entries+1 <= MAX_PACKED_NUMHASH)
#define ADD_DIRECT(table, key, value, hash_val, bin_pos)\
do {\
st_table_entry *entry;\
if ((table)->num_entries > ST_DEFAULT_MAX_DENSITY * (table)->num_bins) {\
rehash(table);\
(bin_pos) = (hash_val) % (table)->num_bins;\
}\
\
entry = alloc(st_table_entry);\
\
entry->hash = (hash_val);\
entry->key = (key);\
entry->record = (value);\
entry->next = (table)->bins[(bin_pos)];\
if ((table)->head != 0) {\
entry->fore = 0;\
(entry->back = (table)->tail)->fore = entry;\
(table)->tail = entry;\
}\
else {\
(table)->head = (table)->tail = entry;\
entry->fore = entry->back = 0;\
}\
(table)->bins[(bin_pos)] = entry;\
(table)->num_entries++;\
} while (0)
static void
unpack_entries(register st_table *table)
{
st_index_t i;
struct st_table_entry *packed_bins[MAX_PACKED_NUMHASH*2];
st_table tmp_table = *table;
memcpy(packed_bins, table->bins, sizeof(struct st_table_entry *) * table->num_entries*2);
table->bins = packed_bins;
tmp_table.entries_packed = 0;
tmp_table.num_entries = 0;
memset(tmp_table.bins, 0, sizeof(struct st_table_entry *) * tmp_table.num_bins);
for (i = 0; i < table->num_entries; i++) {
st_insert(&tmp_table, (st_data_t)packed_bins[i*2], (st_data_t)packed_bins[i*2+1]);
}
*table = tmp_table;
}
int
st_insert(register st_table *table, register st_data_t key, st_data_t value)
{
st_index_t hash_val, bin_pos;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == key) {
table->bins[i*2+1] = (struct st_table_entry*)value;
return 1;
}
}
if (MORE_PACKABLE_P(table)) {
i = table->num_entries++;
table->bins[i*2] = (struct st_table_entry*)key;
table->bins[i*2+1] = (struct st_table_entry*)value;
return 0;
}
else {
unpack_entries(table);
}
}
hash_val = do_hash(key, table);
FIND_ENTRY(table, ptr, hash_val, bin_pos);
if (ptr == 0) {
ADD_DIRECT(table, key, value, hash_val, bin_pos);
return 0;
}
else {
ptr->record = value;
return 1;
}
}
int
st_insert2(register st_table *table, register st_data_t key, st_data_t value,
st_data_t (*func)(st_data_t))
{
st_index_t hash_val, bin_pos;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == key) {
table->bins[i*2+1] = (struct st_table_entry*)value;
return 1;
}
}
if (MORE_PACKABLE_P(table)) {
i = table->num_entries++;
table->bins[i*2] = (struct st_table_entry*)key;
table->bins[i*2+1] = (struct st_table_entry*)value;
return 0;
}
else {
unpack_entries(table);
}
}
hash_val = do_hash(key, table);
FIND_ENTRY(table, ptr, hash_val, bin_pos);
if (ptr == 0) {
key = (*func)(key);
ADD_DIRECT(table, key, value, hash_val, bin_pos);
return 0;
}
else {
ptr->record = value;
return 1;
}
}
void
st_add_direct(st_table *table, st_data_t key, st_data_t value)
{
st_index_t hash_val, bin_pos;
if (table->entries_packed) {
int i;
if (MORE_PACKABLE_P(table)) {
i = table->num_entries++;
table->bins[i*2] = (struct st_table_entry*)key;
table->bins[i*2+1] = (struct st_table_entry*)value;
return;
}
else {
unpack_entries(table);
}
}
hash_val = do_hash(key, table);
bin_pos = hash_val % table->num_bins;
ADD_DIRECT(table, key, value, hash_val, bin_pos);
}
static void
rehash(register st_table *table)
{
register st_table_entry *ptr, **new_bins;
st_index_t i, new_num_bins, hash_val;
new_num_bins = new_size(table->num_bins+1);
new_bins = (st_table_entry**)
xrealloc(table->bins, new_num_bins * sizeof(st_table_entry*));
for (i = 0; i < new_num_bins; ++i) new_bins[i] = 0;
table->num_bins = new_num_bins;
table->bins = new_bins;
if ((ptr = table->head) != 0) {
do {
hash_val = ptr->hash % new_num_bins;
ptr->next = new_bins[hash_val];
new_bins[hash_val] = ptr;
} while ((ptr = ptr->fore) != 0);
}
}
st_table*
st_copy(st_table *old_table)
{
st_table *new_table;
st_table_entry *ptr, *entry, *prev, **tail;
st_index_t num_bins = old_table->num_bins;
st_index_t hash_val;
new_table = alloc(st_table);
if (new_table == 0) {
return 0;
}
*new_table = *old_table;
new_table->bins = (st_table_entry**)
Calloc((unsigned)num_bins, sizeof(st_table_entry*));
if (new_table->bins == 0) {
free(new_table);
return 0;
}
if (old_table->entries_packed) {
memcpy(new_table->bins, old_table->bins, sizeof(struct st_table_entry *) * old_table->num_bins);
return new_table;
}
if ((ptr = old_table->head) != 0) {
prev = 0;
tail = &new_table->head;
do {
entry = alloc(st_table_entry);
if (entry == 0) {
st_free_table(new_table);
return 0;
}
*entry = *ptr;
hash_val = entry->hash % num_bins;
entry->next = new_table->bins[hash_val];
new_table->bins[hash_val] = entry;
entry->back = prev;
*tail = prev = entry;
tail = &entry->fore;
} while ((ptr = ptr->fore) != 0);
new_table->tail = prev;
}
return new_table;
}
#define REMOVE_ENTRY(table, ptr) do \
{ \
if ((ptr)->fore == 0 && (ptr)->back == 0) { \
(table)->head = 0; \
(table)->tail = 0; \
} \
else { \
st_table_entry *fore = (ptr)->fore, *back = (ptr)->back; \
if (fore) fore->back = back; \
if (back) back->fore = fore; \
if ((ptr) == (table)->head) (table)->head = fore; \
if ((ptr) == (table)->tail) (table)->tail = back; \
} \
(table)->num_entries--; \
} while (0)
int
st_delete(register st_table *table, register st_data_t *key, st_data_t *value)
{
st_index_t hash_val;
st_table_entry **prev;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == *key) {
if (value != 0) *value = (st_data_t)table->bins[i*2+1];
table->num_entries--;
memmove(&table->bins[i*2], &table->bins[(i+1)*2],
sizeof(struct st_table_entry*) * 2*(table->num_entries-i));
return 1;
}
}
if (value != 0) *value = 0;
return 0;
}
hash_val = do_hash_bin(*key, table);
for (prev = &table->bins[hash_val]; (ptr = *prev) != 0; prev = &ptr->next) {
if (EQUAL(table, *key, ptr->key)) {
*prev = ptr->next;
REMOVE_ENTRY(table, ptr);
if (value != 0) *value = ptr->record;
*key = ptr->key;
free(ptr);
return 1;
}
}
if (value != 0) *value = 0;
return 0;
}
int
st_delete_safe(register st_table *table, register st_data_t *key, st_data_t *value, st_data_t never)
{
st_index_t hash_val;
register st_table_entry *ptr;
if (table->entries_packed) {
st_index_t i;
for (i = 0; i < table->num_entries; i++) {
if ((st_data_t)table->bins[i*2] == *key) {
if (value != 0) *value = (st_data_t)table->bins[i*2+1];
table->bins[i*2] = (void *)never;
return 1;
}
}
if (value != 0) *value = 0;
return 0;
}
hash_val = do_hash_bin(*key, table);
ptr = table->bins[hash_val];
for (; ptr != 0; ptr = ptr->next) {
if ((ptr->key != never) && EQUAL(table, ptr->key, *key)) {
REMOVE_ENTRY(table, ptr);
*key = ptr->key;
if (value != 0) *value = ptr->record;
ptr->key = ptr->record = never;
return 1;
}
}
if (value != 0) *value = 0;
return 0;
}
void
st_cleanup_safe(st_table *table, st_data_t never)
{
st_table_entry *ptr, **last, *tmp;
st_index_t i;
if (table->entries_packed) {
st_index_t i = 0, j = 0;
while ((st_data_t)table->bins[i*2] != never) {
if (i++ == table->num_entries) return;
}
for (j = i; ++i < table->num_entries;) {
if ((st_data_t)table->bins[i*2] == never) continue;
table->bins[j*2] = table->bins[i*2];
table->bins[j*2+1] = table->bins[i*2+1];
j++;
}
table->num_entries = j;
return;
}
for (i = 0; i < table->num_bins; i++) {
ptr = *(last = &table->bins[i]);
while (ptr != 0) {
if (ptr->key == never) {
tmp = ptr;
*last = ptr = ptr->next;
free(tmp);
}
else {
ptr = *(last = &ptr->next);
}
}
}
}
int
st_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)
{
st_table_entry *ptr, **last, *tmp;
enum st_retval retval;
st_index_t i;
if (table->entries_packed) {
for (i = 0; i < table->num_entries; i++) {
st_index_t j;
st_data_t key, val;
key = (st_data_t)table->bins[i*2];
val = (st_data_t)table->bins[i*2+1];
retval = (*func)(key, val, arg);
if (!table->entries_packed) {
FIND_ENTRY(table, ptr, key, i);
if (retval == ST_CHECK) {
if (!ptr) goto deleted;
goto unpacked_continue;
}
goto unpacked;
}
switch (retval) {
case ST_CHECK: /* check if hash is modified during iteration */
for (j = 0; j < table->num_entries; j++) {
if ((st_data_t)table->bins[j*2] == key)
break;
}
if (j == table->num_entries) {
goto deleted;
}
/* fall through */
case ST_CONTINUE:
break;
case ST_STOP:
return 0;
case ST_DELETE:
table->num_entries--;
memmove(&table->bins[i*2], &table->bins[(i+1)*2],
sizeof(struct st_table_entry*) * 2*(table->num_entries-i));
i--;
break;
}
}
return 0;
}
else {
ptr = table->head;
}
if (ptr != 0) {
do {
i = ptr->hash % table->num_bins;
retval = (*func)(ptr->key, ptr->record, arg);
unpacked:
switch (retval) {
case ST_CHECK: /* check if hash is modified during iteration */
for (tmp = table->bins[i]; tmp != ptr; tmp = tmp->next) {
if (!tmp) {
deleted:
/* call func with error notice */
retval = (*func)(0, 0, arg, 1);
return 1;
}
}
/* fall through */
case ST_CONTINUE:
unpacked_continue:
ptr = ptr->fore;
break;
case ST_STOP:
return 0;
case ST_DELETE:
last = &table->bins[ptr->hash % table->num_bins];
for (; (tmp = *last) != 0; last = &tmp->next) {
if (ptr == tmp) {
tmp = ptr->fore;
*last = ptr->next;
REMOVE_ENTRY(table, ptr);
free(ptr);
if (ptr == tmp) return 0;
ptr = tmp;
break;
}
}
}
} while (ptr && table->head);
}
return 0;
}
#if 0 /* unused right now */
int
st_reverse_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)
{
st_table_entry *ptr, **last, *tmp;
enum st_retval retval;
int i;
if (table->entries_packed) {
for (i = table->num_entries-1; 0 <= i; i--) {
int j;
st_data_t key, val;
key = (st_data_t)table->bins[i*2];
val = (st_data_t)table->bins[i*2+1];
retval = (*func)(key, val, arg);
switch (retval) {
case ST_CHECK: /* check if hash is modified during iteration */
for (j = 0; j < table->num_entries; j++) {
if ((st_data_t)table->bins[j*2] == key)
break;
}
if (j == table->num_entries) {
/* call func with error notice */
retval = (*func)(0, 0, arg, 1);
return 1;
}
/* fall through */
case ST_CONTINUE:
break;
case ST_STOP:
return 0;
case ST_DELETE:
table->num_entries--;
memmove(&table->bins[i*2], &table->bins[(i+1)*2],
sizeof(struct st_table_entry*) * 2*(table->num_entries-i));
break;
}
}
return 0;
}
if ((ptr = table->head) != 0) {
ptr = ptr->back;
do {
retval = (*func)(ptr->key, ptr->record, arg, 0);
switch (retval) {
case ST_CHECK: /* check if hash is modified during iteration */
i = ptr->hash % table->num_bins;
for (tmp = table->bins[i]; tmp != ptr; tmp = tmp->next) {
if (!tmp) {
/* call func with error notice */
retval = (*func)(0, 0, arg, 1);
return 1;
}
}
/* fall through */
case ST_CONTINUE:
ptr = ptr->back;
break;
case ST_STOP:
return 0;
case ST_DELETE:
last = &table->bins[ptr->hash % table->num_bins];
for (; (tmp = *last) != 0; last = &tmp->next) {
if (ptr == tmp) {
tmp = ptr->back;
*last = ptr->next;
REMOVE_ENTRY(table, ptr);
free(ptr);
ptr = tmp;
break;
}
}
ptr = ptr->next;
free(tmp);
table->num_entries--;
}
} while (ptr && table->head);
}
return 0;
}
#endif
/*
* hash_32 - 32 bit Fowler/Noll/Vo FNV-1a hash code
*
* @(#) $Hash32: Revision: 1.1 $
* @(#) $Hash32: Id: hash_32a.c,v 1.1 2003/10/03 20:38:53 chongo Exp $
* @(#) $Hash32: Source: /usr/local/src/cmd/fnv/RCS/hash_32a.c,v $
*
***
*
* Fowler/Noll/Vo hash
*
* The basis of this hash algorithm was taken from an idea sent
* as reviewer comments to the IEEE POSIX P1003.2 committee by:
*
* Phong Vo (http://www.research.att.com/info/kpv/)
* Glenn Fowler (http://www.research.att.com/~gsf/)
*
* In a subsequent ballot round:
*
* Landon Curt Noll (http://www.isthe.com/chongo/)
*
* improved on their algorithm. Some people tried this hash
* and found that it worked rather well. In an EMail message
* to Landon, they named it the ``Fowler/Noll/Vo'' or FNV hash.
*
* FNV hashes are designed to be fast while maintaining a low
* collision rate. The FNV speed allows one to quickly hash lots
* of data while maintaining a reasonable collision rate. See:
*
* http://www.isthe.com/chongo/tech/comp/fnv/index.html
*
* for more details as well as other forms of the FNV hash.
***
*
* To use the recommended 32 bit FNV-1a hash, pass FNV1_32A_INIT as the
* Fnv32_t hashval argument to fnv_32a_buf() or fnv_32a_str().
*
***
*
* Please do not copyright this code. This code is in the public domain.
*
* LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
* EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*
* By:
* chongo <Landon Curt Noll> /\oo/\
* http://www.isthe.com/chongo/
*
* Share and Enjoy! :-)
*/
/*
* 32 bit FNV-1 and FNV-1a non-zero initial basis
*
* The FNV-1 initial basis is the FNV-0 hash of the following 32 octets:
*
* chongo <Landon Curt Noll> /\../\
*
* NOTE: The \'s above are not back-slashing escape characters.
* They are literal ASCII backslash 0x5c characters.
*
* NOTE: The FNV-1a initial basis is the same value as FNV-1 by definition.
*/
#define FNV1_32A_INIT 0x811c9dc5
/*
* 32 bit magic FNV-1a prime
*/
#define FNV_32_PRIME 0x01000193
#ifdef ST_USE_FNV1
static st_index_t
strhash(st_data_t arg)
{
register const char *string = (const char *)arg;
register st_index_t hval = FNV1_32A_INIT;
/*
* FNV-1a hash each octet in the buffer
*/
while (*string) {
/* xor the bottom with the current octet */
hval ^= (unsigned int)*string++;
/* multiply by the 32 bit FNV magic prime mod 2^32 */
hval *= FNV_32_PRIME;
}
return hval;
}
#else
#ifndef UNALIGNED_WORD_ACCESS
# if defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
defined(__x86_64) || defined(__x86_64__) || defined(_M_AMD86) || \
defined(__mc68020__)
# define UNALIGNED_WORD_ACCESS 1
# endif
#endif
#ifndef UNALIGNED_WORD_ACCESS
# define UNALIGNED_WORD_ACCESS 0
#endif
/* MurmurHash described in http://murmurhash.googlepages.com/ */
#ifndef MURMUR
#define MURMUR 2
#endif
#define MurmurMagic_1 (st_index_t)0xc6a4a793
#define MurmurMagic_2 (st_index_t)0x5bd1e995
#if MURMUR == 1
#define MurmurMagic MurmurMagic_1
#elif MURMUR == 2
#if SIZEOF_ST_INDEX_T > 4
#define MurmurMagic ((MurmurMagic_1 << 32) | MurmurMagic_2)
#else
#define MurmurMagic MurmurMagic_2
#endif
#endif
static inline st_index_t
murmur(st_index_t h, st_index_t k, int r)
{
const st_index_t m = MurmurMagic;
#if MURMUR == 1
h += k;
h *= m;
h ^= h >> r;
#elif MURMUR == 2
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
#endif
return h;
}
static inline st_index_t
murmur_finish(st_index_t h)
{
#if MURMUR == 1
h = murmur(h, 0, 10);
h = murmur(h, 0, 17);
#elif MURMUR == 2
h ^= h >> 13;
h *= MurmurMagic;
h ^= h >> 15;
#endif
return h;
}
#define murmur_step(h, k) murmur((h), (k), 16)
#if MURMUR == 1
#define murmur1(h) murmur_step((h), 16)
#else
#define murmur1(h) murmur_step((h), 24)
#endif
st_index_t
st_hash(const void *ptr, size_t len, st_index_t h)
{
const char *data = ptr;
st_index_t t = 0;
h += 0xdeadbeef;
#define data_at(n) (st_index_t)((unsigned char)data[(n)])
#define UNALIGNED_ADD_4 UNALIGNED_ADD(2); UNALIGNED_ADD(1); UNALIGNED_ADD(0)
#if SIZEOF_ST_INDEX_T > 4
#define UNALIGNED_ADD_8 UNALIGNED_ADD(6); UNALIGNED_ADD(5); UNALIGNED_ADD(4); UNALIGNED_ADD(3); UNALIGNED_ADD_4
#if SIZEOF_ST_INDEX_T > 8
#define UNALIGNED_ADD_16 UNALIGNED_ADD(14); UNALIGNED_ADD(13); UNALIGNED_ADD(12); UNALIGNED_ADD(11); \
UNALIGNED_ADD(10); UNALIGNED_ADD(9); UNALIGNED_ADD(8); UNALIGNED_ADD(7); UNALIGNED_ADD_8
#define UNALIGNED_ADD_ALL UNALIGNED_ADD_16
#endif
#define UNALIGNED_ADD_ALL UNALIGNED_ADD_8
#else
#define UNALIGNED_ADD_ALL UNALIGNED_ADD_4
#endif
if (len >= sizeof(st_index_t)) {
#if !UNALIGNED_WORD_ACCESS
int align = (int)((st_data_t)data % sizeof(st_index_t));
if (align) {
st_index_t d = 0;
int sl, sr, pack;
switch (align) {
#ifdef WORDS_BIGENDIAN
# define UNALIGNED_ADD(n) case SIZEOF_ST_INDEX_T - (n) - 1: \
t |= data_at(n) << CHAR_BIT*(SIZEOF_ST_INDEX_T - (n) - 2)
#else
# define UNALIGNED_ADD(n) case SIZEOF_ST_INDEX_T - (n) - 1: \
t |= data_at(n) << CHAR_BIT*(n)
#endif
UNALIGNED_ADD_ALL;
#undef UNALIGNED_ADD
}
#ifdef WORDS_BIGENDIAN
t >>= (CHAR_BIT * align) - CHAR_BIT;
#else
t <<= (CHAR_BIT * align);
#endif
data += sizeof(st_index_t)-align;
len -= sizeof(st_index_t)-align;
sl = CHAR_BIT * (SIZEOF_ST_INDEX_T-align);
sr = CHAR_BIT * align;
while (len >= sizeof(st_index_t)) {
d = *(st_index_t *)data;
#ifdef WORDS_BIGENDIAN
t = (t << sr) | (d >> sl);
#else
t = (t >> sr) | (d << sl);
#endif
h = murmur_step(h, t);
t = d;
data += sizeof(st_index_t);
len -= sizeof(st_index_t);
}
pack = len < (size_t)align ? (int)len : align;
d = 0;
switch (pack) {
#ifdef WORDS_BIGENDIAN
# define UNALIGNED_ADD(n) case (n) + 1: \
d |= data_at(n) << CHAR_BIT*(SIZEOF_ST_INDEX_T - (n) - 1)
#else
# define UNALIGNED_ADD(n) case (n) + 1: \
d |= data_at(n) << CHAR_BIT*(n)
#endif
UNALIGNED_ADD_ALL;
#undef UNALIGNED_ADD
}
#ifdef WORDS_BIGENDIAN
t = (t << sr) | (d >> sl);
#else
t = (t >> sr) | (d << sl);
#endif
#if MURMUR == 2
if (len < (size_t)align) goto skip_tail;
#endif
h = murmur_step(h, t);
data += pack;
len -= pack;
}
else
#endif
{
do {
h = murmur_step(h, *(st_index_t *)data);
data += sizeof(st_index_t);
len -= sizeof(st_index_t);
} while (len >= sizeof(st_index_t));
}
}
t = 0;
switch (len) {
#ifdef WORDS_BIGENDIAN
# define UNALIGNED_ADD(n) case (n) + 1: \
t |= data_at(n) << CHAR_BIT*(SIZEOF_ST_INDEX_T - (n) - 1)
#else
# define UNALIGNED_ADD(n) case (n) + 1: \
t |= data_at(n) << CHAR_BIT*(n)
#endif
UNALIGNED_ADD_ALL;
#undef UNALIGNED_ADD
#if MURMUR == 1
h = murmur_step(h, t);
#elif MURMUR == 2
# if !UNALIGNED_WORD_ACCESS
skip_tail:
# endif
h ^= t;
h *= MurmurMagic;
#endif
}
return murmur_finish(h);
}
st_index_t
st_hash_uint32(st_index_t h, uint32_t i)
{
return murmur_step(h + i, 16);
}
st_index_t
st_hash_uint(st_index_t h, st_index_t i)
{
st_index_t v = 0;
h += i;
#ifdef WORDS_BIGENDIAN
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 12*8
v = murmur1(v + (h >> 12*8));
#endif
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 8*8
v = murmur1(v + (h >> 8*8));
#endif
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 4*8
v = murmur1(v + (h >> 4*8));
#endif
#endif
v = murmur1(v + h);
#ifndef WORDS_BIGENDIAN
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 4*8
v = murmur1(v + (h >> 4*8));
#endif
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 8*8
v = murmur1(v + (h >> 8*8));
#endif
#if SIZEOF_ST_INDEX_T*CHAR_BIT > 12*8
v = murmur1(v + (h >> 12*8));
#endif
#endif
return v;
}
st_index_t
st_hash_end(st_index_t h)
{
h = murmur_step(h, 10);
h = murmur_step(h, 17);
return h;
}
#undef st_hash_start
st_index_t
st_hash_start(st_index_t h)
{
return h;
}
static st_index_t
strhash(st_data_t arg)
{
register const char *string = (const char *)arg;
return st_hash(string, strlen(string), FNV1_32A_INIT);
}
#endif
int
st_strcasecmp(const char *s1, const char *s2)
{
unsigned int c1, c2;
while (1) {
c1 = (unsigned char)*s1++;
c2 = (unsigned char)*s2++;
if (c1 == '\0' || c2 == '\0') {
if (c1 != '\0') return 1;
if (c2 != '\0') return -1;
return 0;
}
if ((unsigned int)(c1 - 'A') <= ('Z' - 'A')) c1 += 'a' - 'A';
if ((unsigned int)(c2 - 'A') <= ('Z' - 'A')) c2 += 'a' - 'A';
if (c1 != c2) {
if (c1 > c2)
return 1;
else
return -1;
}
}
}
int
st_strncasecmp(const char *s1, const char *s2, size_t n)
{
unsigned int c1, c2;
while (n--) {
c1 = (unsigned char)*s1++;
c2 = (unsigned char)*s2++;
if (c1 == '\0' || c2 == '\0') {
if (c1 != '\0') return 1;
if (c2 != '\0') return -1;
return 0;
}
if ((unsigned int)(c1 - 'A') <= ('Z' - 'A')) c1 += 'a' - 'A';
if ((unsigned int)(c2 - 'A') <= ('Z' - 'A')) c2 += 'a' - 'A';
if (c1 != c2) {
if (c1 > c2)
return 1;
else
return -1;
}
}
return 0;
}
static st_index_t
strcasehash(st_data_t arg)
{
register const char *string = (const char *)arg;
register st_index_t hval = FNV1_32A_INIT;
/*
* FNV-1a hash each octet in the buffer
*/
while (*string) {
unsigned int c = (unsigned char)*string++;
if ((unsigned int)(c - 'A') <= ('Z' - 'A')) c += 'a' - 'A';
hval ^= c;
/* multiply by the 32 bit FNV magic prime mod 2^32 */
hval *= FNV_32_PRIME;
}
return hval;
}
int
st_numcmp(st_data_t x, st_data_t y)
{
return x != y;
}
st_index_t
st_numhash(st_data_t n)
{
return (st_index_t)n;
}