gecko-dev/expat/xmlparse/hashtable.c

128 lines
2.5 KiB
C

/*
Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
Portions Copyright (c) 1999 Netscape Communications Corporation.
See the file COPYING for copying permission.
*/
#include "xmldef.h"
#ifdef XML_UNICODE_WCHAR_T
#ifndef XML_UNICODE
#define XML_UNICODE
#endif
#endif
#include "hashtable.h"
#define INIT_SIZE 64
static
int keyeq(KEY s1, KEY s2)
{
for (; *s1 == *s2; s1++, s2++)
if (*s1 == 0)
return 1;
return 0;
}
static
unsigned long hash(KEY s)
{
unsigned long h = 0;
while (*s)
h = (h << 5) + h + (unsigned char)*s++;
return h;
}
NAMED *lookup(HASH_TABLE *table, KEY name, size_t createSize)
{
size_t i;
if (table->size == 0) {
if (!createSize)
return 0;
table->v = calloc(INIT_SIZE, sizeof(NAMED *));
if (!table->v)
return 0;
table->size = INIT_SIZE;
table->usedLim = INIT_SIZE / 2;
i = hash(name) & (table->size - 1);
}
else {
unsigned long h = hash(name);
for (i = h & (table->size - 1);
table->v[i];
i == 0 ? i = table->size - 1 : --i) {
if (keyeq(name, table->v[i]->name))
return table->v[i];
}
if (!createSize)
return 0;
if (table->used == table->usedLim) {
/* check for overflow */
size_t newSize = table->size * 2;
NAMED **newV = calloc(newSize, sizeof(NAMED *));
if (!newV)
return 0;
for (i = 0; i < table->size; i++)
if (table->v[i]) {
size_t j;
for (j = hash(table->v[i]->name) & (newSize - 1);
newV[j];
j == 0 ? j = newSize - 1 : --j)
;
newV[j] = table->v[i];
}
free(table->v);
table->v = newV;
table->size = newSize;
table->usedLim = newSize/2;
for (i = h & (table->size - 1);
table->v[i];
i == 0 ? i = table->size - 1 : --i)
;
}
}
table->v[i] = calloc(1, createSize);
if (!table->v[i])
return 0;
table->v[i]->name = name;
(table->used)++;
return table->v[i];
}
void hashTableDestroy(HASH_TABLE *table)
{
size_t i;
for (i = 0; i < table->size; i++) {
NAMED *p = table->v[i];
if (p)
free(p);
}
free(table->v);
}
void hashTableInit(HASH_TABLE *p)
{
p->size = 0;
p->usedLim = 0;
p->used = 0;
p->v = 0;
}
void hashTableIterInit(HASH_TABLE_ITER *iter, const HASH_TABLE *table)
{
iter->p = table->v;
iter->end = iter->p + table->size;
}
NAMED *hashTableIterNext(HASH_TABLE_ITER *iter)
{
while (iter->p != iter->end) {
NAMED *tem = *(iter->p)++;
if (tem)
return tem;
}
return 0;
}