px4-firmware/apps/examples/udp/udp-server.c

174 lines
5.2 KiB
C

/****************************************************************************
* examples/udp/udp-server.c
*
* Copyright (C) 2007, 2009, 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 Gregory Nutt 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 <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include "udp-internal.h"
/****************************************************************************
* Private Functions
****************************************************************************/
static inline int check_buffer(unsigned char *buf)
{
int ret = 1;
int offset;
int ch;
int j;
offset = buf[0];
for (ch = 0x20, j = offset + 1; ch < 0x7f; ch++, j++)
{
if (j >= SENDSIZE)
{
j = 1;
}
if (buf[j] != ch)
{
message("server: Buffer content error for offset=%d, index=%d\n", offset, j);
ret = 0;
}
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
void recv_server(void)
{
struct sockaddr_in server;
struct sockaddr_in client;
in_addr_t tmpaddr;
unsigned char inbuf[1024];
int sockfd;
int nbytes;
int optval;
int offset;
socklen_t addrlen;
/* Create a new UDP socket */
sockfd = socket(PF_INET, SOCK_DGRAM, 0);
if (sockfd < 0)
{
message("server: socket failure: %d\n", errno);
exit(1);
}
/* Set socket to reuse address */
optval = 1;
if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (void*)&optval, sizeof(int)) < 0)
{
message("server: setsockopt SO_REUSEADDR failure: %d\n", errno);
exit(1);
}
/* Bind the socket to a local address */
server.sin_family = AF_INET;
server.sin_port = HTONS(PORTNO);
server.sin_addr.s_addr = HTONL(INADDR_ANY);
if (bind(sockfd, (struct sockaddr*)&server, sizeof(struct sockaddr_in)) < 0)
{
message("server: bind failure: %d\n", errno);
exit(1);
}
/* Then receive up to 256 packets of data */
for (offset = 0; offset < 256; offset++)
{
message("server: %d. Receiving up 1024 bytes\n", offset);
addrlen = sizeof(struct sockaddr_in);
nbytes = recvfrom(sockfd, inbuf, 1024, 0,
(struct sockaddr*)&client, &addrlen);
tmpaddr = ntohl(client.sin_addr.s_addr);
message("server: %d. Received %d bytes from %d.%d.%d.%d:%d\n",
offset, nbytes,
tmpaddr >> 24, (tmpaddr >> 16) & 0xff,
(tmpaddr >> 8) & 0xff, tmpaddr & 0xff,
ntohs(client.sin_port));
if (nbytes < 0)
{
message("server: %d. recv failed: %d\n", offset, errno);
close(sockfd);
exit(-1);
}
if (nbytes != SENDSIZE)
{
message("server: %d. recv size incorrect: %d vs %d\n", offset, nbytes, SENDSIZE);
close(sockfd);
exit(-1);
}
if (offset < inbuf[0])
{
message("server: %d. %d packets lost, resetting offset\n", offset, inbuf[0] - offset);
offset = inbuf[0];
}
else if (offset > inbuf[0])
{
message("server: %d. Bad offset in buffer: %d\n", offset, inbuf[0]);
close(sockfd);
exit(-1);
}
if (!check_buffer(inbuf))
{
message("server: %d. Bad buffer contents\n", offset);
close(sockfd);
exit(-1);
}
}
close(sockfd);
}