transmission/third-party/miniupnp/codelength.h

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/* $Id: codelength.h,v 1.3 2011/07/30 13:10:05 nanard Exp $ */
/* Project : miniupnp
* Author : Thomas BERNARD
* copyright (c) 2005-2011 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) && (n<(1<<25)));
#define DECODELENGTH_CHECKLIMIT(n, p, p_limit) \
n = 0; \
do { \
if((p) >= (p_limit)) break; \
n = (n << 7) | (*(p) & 0x7f); \
} while((*((p)++)&0x80) && (n<(1<<25)));
#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