header.c
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/**
* \file
* Interface implementation for HTTP header class.
*
* \author Georg Hopp
*
* \copyright
* Copyright (C) 2012 Georg Hopp
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "class.h"
#include "interface/class.h"
#include "http/header.h"
/**
* SDBM hashing algorithm:
*
* this algorithm was created for sdbm (a public-domain reimplementation of
* ndbm) database library. it was found to do well in scrambling bits,
* causing better distribution of the keys and fewer splits. it also happens
* to be a good general hashing function with good distribution. the actual
* function is hash(i) = hash(i - 1) * 65599 + str[i]; what is included below
* is the faster version used in gawk. [there is even a faster, duff-device
* version] the magic constant 65599 was picked out of thin air while
* experimenting with different constants, and turns out to be a prime. this
* is one of the algorithms used in berkeley db (see sleepycat) and elsewhere.
*/
static
inline
unsigned long
sdbm(unsigned char * str)
{
unsigned long hash = 0;
int c;
while ((c = tolower(*str++)))
hash = c + (hash << 6) + (hash << 16) - hash;
return hash;
}
static
void
ctor(void * _this, va_list * params) {
HttpHeader this = _this;
char * name;
char * value;
name = va_arg(* params, char *);
value = va_arg(* params, char *);
this->name = malloc(strlen(name) + 1);
strcpy(this->name, name);
this->hash = sdbm((unsigned char *)name);
this->value = malloc(strlen(value) + 1);
strcpy(this->value, value);
}
static
void
dtor(void * _this)
{
HttpHeader this = _this;
free(this->name);
free(this->value);
}
INIT_IFACE(Class, ctor, dtor, NULL);
CREATE_CLASS(HttpHeader, NULL, IFACE(Class));
// vim: set ts=4 sw=4: