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/* ==========================================================================
Licensed under BSD 2clause license See LICENSE file for more information
Author: Michał Łyszczek <michal.lyszczek@bofc.pl>
==========================================================================
_ __ __ ____ _ __
(_)____ _____ / /__ __ ____/ /___ / __/(_)/ /___ _____
/ // __ \ / ___// // / / // __ // _ \ / /_ / // // _ \ / ___/
/ // / / // /__ / // /_/ // /_/ // __/ / __// // // __/(__ )
/_//_/ /_/ \___//_/ \__,_/ \__,_/ \___/ /_/ /_//_/ \___//____/
========================================================================== */
#include "el-private.h"
#include <limits.h>
/* ==========================================================================
__ __ _ ____
____ __ __ / /_ / /(_)_____ / __/__ __ ____ _____ _____
/ __ \ / / / // __ \ / // // ___/ / /_ / / / // __ \ / ___// ___/
/ /_/ // /_/ // /_/ // // // /__ / __// /_/ // / / // /__ (__ )
/ .___/ \__,_//_.___//_//_/ \___/ /_/ \__,_//_/ /_/ \___//____/
/_/
========================================================================== */
/* ==========================================================================
Decodes encoded 'number' and stores value into 'out'. Check description
of el_encode_number for more information.
returns number of bytes processed from 'number'
========================================================================== */
size_t el_decode_number
(
const void *number, /* number to decode */
#ifdef LLONG_MAX
unsigned long long *out /* decoded number */
#else
unsigned long *out /* decoded number */
#endif
)
{
const unsigned char *n; /* just a 'number' as unsigned cahr */
size_t i; /* temporary index */
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
i = 0;
*out = 0;
n = number;
do
{
/* multiple stuff is happening in this one-liner
*
* - first we take 7 bits of number
* - calculate weigth of current number
* - set current number into right position of out
*/
#ifdef LLONG_MAX
*out |= (unsigned long long)(n[i] & 0x7f) << (i * 7);
#else
*out |= (unsigned long)(n[i] & 0x7f) << (i * 7);
#endif
/* we do this until number lacks of continuation bit, which means
* we are done
*/
}
while (n[i++] & 0x80);
/* return number of bytes processed from 'number'
*/
return i;
}
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