summaryrefslogtreecommitdiffstats
path: root/src/upnp/codelength.h
blob: f11e5e9367cb6e6e1635a05cc6dcf709549ee857 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
/* $Id: codelength.h,v 1.1 2008/10/06 22:04:06 nanard Exp $ */
/* Project : miniupnp
 * Author : Thomas BERNARD
 * copyright (c) 2005-2008 Thomas Bernard
 * This software is subjet to the conditions detailed in the
 * provided LICENCE file. */
#ifndef __CODELENGTH_H__
#define __CODELENGTH_H__

/* Encode length by using 7bit per Byte :
 * Most significant bit of each byte specifies that the
 * following byte is part of the code */
#define DECODELENGTH(n, p) n = 0; \
                           do { n = (n << 7) | (*p & 0x7f); } \
                           while(*(p++)&0x80);

#define CODELENGTH(n, p) if(n>=268435456) *(p++) = (n >> 28) | 0x80; \
                         if(n>=2097152) *(p++) = (n >> 21) | 0x80; \
                         if(n>=16384) *(p++) = (n >> 14) | 0x80; \
                         if(n>=128) *(p++) = (n >> 7) | 0x80; \
                         *(p++) = n & 0x7f;

#endif