File: inet_net_ntop.c

package info (click to toggle)
glibc 2.19-18+deb8u7
  • links: PTS, VCS
  • area: main
  • in suites: jessie-backports
  • size: 204,748 kB
  • sloc: ansic: 970,427; asm: 241,207; sh: 10,069; makefile: 8,476; cpp: 3,595; perl: 2,077; pascal: 1,839; awk: 1,704; yacc: 317; sed: 73
file content (140 lines) | stat: -rw-r--r-- 3,328 bytes parent folder | download | duplicates (15)
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
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/*
 * Copyright (c) 1996,1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$BINDId: inet_net_ntop.c,v 1.6 1999/01/08 19:23:42 vixie Exp $";
#endif

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#ifdef SPRINTF_CHAR
# define SPRINTF(x) strlen(sprintf/**/x)
#else
# define SPRINTF(x) ((size_t)sprintf x)
#endif

static char *	inet_net_ntop_ipv4 (const u_char *src, int bits,
				    char *dst, size_t size) __THROW;

/*
 * char *
 * inet_net_ntop(af, src, bits, dst, size)
 *	convert network number from network to presentation format.
 *	generates CIDR style result always.
 * return:
 *	pointer to dst, or NULL if an error occurred (check errno).
 * author:
 *	Paul Vixie (ISC), July 1996
 */
char *
inet_net_ntop(af, src, bits, dst, size)
	int af;
	const void *src;
	int bits;
	char *dst;
	size_t size;
{
	switch (af) {
	case AF_INET:
		return (inet_net_ntop_ipv4(src, bits, dst, size));
	default:
		__set_errno (EAFNOSUPPORT);
		return (NULL);
	}
}

/*
 * static char *
 * inet_net_ntop_ipv4(src, bits, dst, size)
 *	convert IPv4 network number from network to presentation format.
 *	generates CIDR style result always.
 * return:
 *	pointer to dst, or NULL if an error occurred (check errno).
 * note:
 *	network byte order assumed.  this means 192.5.5.240/28 has
 *	0b11110000 in its fourth octet.
 * author:
 *	Paul Vixie (ISC), July 1996
 */
static char *
inet_net_ntop_ipv4(src, bits, dst, size)
	const u_char *src;
	int bits;
	char *dst;
	size_t size;
{
	char *odst = dst;
	char *t;
	u_int m;
	int b;

	if (bits < 0 || bits > 32) {
		__set_errno (EINVAL);
		return (NULL);
	}
	if (bits == 0) {
		if (size < sizeof "0")
			goto emsgsize;
		*dst++ = '0';
		size--;
		*dst = '\0';
	}

	/* Format whole octets. */
	for (b = bits / 8; b > 0; b--) {
		if (size < sizeof "255.")
			goto emsgsize;
		t = dst;
		dst += SPRINTF((dst, "%u", *src++));
		if (b > 1) {
			*dst++ = '.';
			*dst = '\0';
		}
		size -= (size_t)(dst - t);
	}

	/* Format partial octet. */
	b = bits % 8;
	if (b > 0) {
		if (size < sizeof ".255")
			goto emsgsize;
		t = dst;
		if (dst != odst)
			*dst++ = '.';
		m = ((1 << b) - 1) << (8 - b);
		dst += SPRINTF((dst, "%u", *src & m));
		size -= (size_t)(dst - t);
	}

	/* Format CIDR /width. */
	if (size < sizeof "/32")
		goto emsgsize;
	dst += SPRINTF((dst, "/%u", bits));
	return (odst);

 emsgsize:
	__set_errno (EMSGSIZE);
	return (NULL);
}