1/* $Id: codelength.h,v 1.3 2011/07/30 13:10:05 nanard Exp $ */ 2/* Project : miniupnp 3 * Author : Thomas BERNARD 4 * copyright (c) 2005-2011 Thomas Bernard 5 * This software is subjet to the conditions detailed in the 6 * provided LICENCE file. */ 7#ifndef __CODELENGTH_H__ 8#define __CODELENGTH_H__ 9 10/* Encode length by using 7bit per Byte : 11 * Most significant bit of each byte specifies that the 12 * following byte is part of the code */ 13#define DECODELENGTH(n, p) n = 0; \ 14 do { n = (n << 7) | (*p & 0x7f); } \ 15 while((*(p++)&0x80) && (n<(1<<25))); 16 17#define DECODELENGTH_CHECKLIMIT(n, p, p_limit) \ 18 n = 0; \ 19 do { \ 20 if((p) >= (p_limit)) break; \ 21 n = (n << 7) | (*(p) & 0x7f); \ 22 } while((*((p)++)&0x80) && (n<(1<<25))); 23 24#define CODELENGTH(n, p) if(n>=268435456) *(p++) = (n >> 28) | 0x80; \ 25 if(n>=2097152) *(p++) = (n >> 21) | 0x80; \ 26 if(n>=16384) *(p++) = (n >> 14) | 0x80; \ 27 if(n>=128) *(p++) = (n >> 7) | 0x80; \ 28 *(p++) = n & 0x7f; 29 30#endif 31 32