File: codelength.h

package info (click to toggle)
minissdpd 1.5.20190210-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 484 kB
  • sloc: ansic: 4,944; sh: 296; makefile: 99
file content (54 lines) | stat: -rw-r--r-- 1,557 bytes parent folder | download | duplicates (6)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
/* $Id: codelength.h,v 1.5 2015/07/09 12:40:18 nanard Exp $ */
/* Project : miniupnp
 * Author : Thomas BERNARD
 * copyright (c) 2005-2015 Thomas Bernard
 * This software is subjet to the conditions detailed in the
 * provided LICENCE file. */
#ifndef CODELENGTH_H_INCLUDED
#define CODELENGTH_H_INCLUDED

/* Encode length by using 7bit per Byte :
 * Most significant bit of each byte specifies that the
 * following byte is part of the code */

/* n : unsigned
 * p : unsigned char *
 */
#define DECODELENGTH(n, p) n = 0; \
                           do { n = (n << 7) | (*p & 0x7f); } \
                           while((*(p++)&0x80) && (n<(1<<25)));

/* n :    unsigned
 * READ : function/macro to read one byte (unsigned char)
 */
#define DECODELENGTH_READ(n, READ) \
	n = 0; \
	do { \
		unsigned char c; \
		READ(c); \
		n = (n << 7) | (c & 0x07f); \
		if(!(c&0x80)) break; \
	} while(n<(1<<25));

/* n :       unsigned
 * p :       unsigned char *
 * p_limit : unsigned char *
 */
#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)));


/* n : unsigned
 * p : unsigned char *
 */
#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 /* CODELENGTH_H_INCLUDED */