#include "php_hash.h"
#include "php_hash_adler32.h"
PHP_HASH_API void PHP_ADLER32Init(PHP_ADLER32_CTX *context)
{
context->state = 1;
}
PHP_HASH_API void PHP_ADLER32Update(PHP_ADLER32_CTX *context, const unsigned char *input, size_t len)
{
php_hash_uint32 i, s[2];
s[0] = context->state & 0xffff;
s[1] = (context->state >> 16) & 0xffff;
for (i = 0; i < len; ++i) {
s[0] += input[i];
s[1] += s[0];
if (s[1]>=0x7fffffff)
{
s[0] = s[0] % 65521;
s[1] = s[1] % 65521;
}
}
s[0] = s[0] % 65521;
s[1] = s[1] % 65521;
context->state = s[0] + (s[1] << 16);
}
PHP_HASH_API void PHP_ADLER32Final(unsigned char digest[4], PHP_ADLER32_CTX *context)
{
digest[0] = (unsigned char) ((context->state >> 24) & 0xff);
digest[1] = (unsigned char) ((context->state >> 16) & 0xff);
digest[2] = (unsigned char) ((context->state >> 8) & 0xff);
digest[3] = (unsigned char) (context->state & 0xff);
context->state = 0;
}
PHP_HASH_API int PHP_ADLER32Copy(const php_hash_ops *ops, PHP_ADLER32_CTX *orig_context, PHP_ADLER32_CTX *copy_context)
{
copy_context->state = orig_context->state;
return SUCCESS;
}
const php_hash_ops php_hash_adler32_ops = {
(php_hash_init_func_t) PHP_ADLER32Init,
(php_hash_update_func_t) PHP_ADLER32Update,
(php_hash_final_func_t) PHP_ADLER32Final,
(php_hash_copy_func_t) PHP_ADLER32Copy,
4,
4,
sizeof(PHP_ADLER32_CTX)
};