incubator-nuttx/libs/libc/net/lib_inetaddr.c

132 lines
4.7 KiB
C

/****************************************************************************
* libs/libc/net/lib_inetaddr.c
*
* Copyright (C) 2011 Yu Qiang. All rights reserved.
* Author: Yu Qiang <yuq825@gmail.com>
*
* This file is a part of NuttX:
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <stdio.h>
#include <arpa/inet.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* name inet_addr
*
* Description:
* The inet_addr() function converts the string pointed to by cp, in the
* standard IPv4 dotted decimal notation, to an integer value suitable for
* use as an Internet address.
*
* inet_aton() returns nonzero if the address is valid, zero if not.
* The address supplied in cp can have one of the following forms:
*
* a.b.c.d Each of the four numeric parts specifies a byte of the address;
* the bytes are assigned in left-to-right order to produce the
* binary address.
*
* a.b.c Parts a and b specify the first two bytes of the binary address.
* Part c is interpreted as a 16-bit value that defines the
* rightmost two bytes of the binary address. This notation is
* suitable for specifying (outmoded) Class B network addresses.
*
* a.b Part a specifies the first byte of the binary address. Part b is
* interpreted as a 24-bit value that defines the rightmost three
* bytes of the binary address. This notation is suitable for
* specifying (outmoded) Class A network addresses.
*
* a The value a is interpreted as a 32-bit value that is stored
* directly into the binary address without any byte rearrangement.
*
* Returned Value:
* If input string cannot be recognized as a valid IPv4 number, function
* returns zero.
*
****************************************************************************/
in_addr_t inet_addr(FAR const char *cp)
{
unsigned int a;
unsigned int b;
unsigned int c;
unsigned int d;
uint32_t result = INADDR_NONE;
switch (sscanf(cp, "%u.%u.%u.%u", &a, &b, &c, &d))
{
case 1:
{
result = a;
break;
}
case 2:
{
if ((a < 0x100) && (b < 0x1000000))
{
result = (((uint32_t)a) << 24) | b;
}
break;
}
case 3:
{
if ((a < 0x100) && (b < 0x100) && (c < 0x10000))
{
result = (((uint32_t)a) << 24) | (((uint32_t)b) << 16) | c;
}
break;
}
case 4:
{
if ((a < 0x100) && (b < 0x100) && (c < 0x100) && (d < 0x100))
{
result = (((uint32_t)a) << 24) | (((uint32_t)b) << 16) |
(((uint32_t)c) << 8) | d;
}
break;
}
}
return HTONL(result);
}