dump1090/anet.c

327 lines
9.7 KiB
C
Raw Permalink Normal View History

2016-02-16 14:00:55 +01:00
// Part of dump1090, a Mode S message decoder for RTLSDR devices.
//
// anet.c: Basic TCP socket stuff made a bit less boring
//
// Copyright (c) 2016 Oliver Jowett <oliver@mutability.co.uk>
//
// This file is free software: you may copy, redistribute and/or modify it
// under the terms of the GNU General Public License as published by the
// Free Software Foundation, either version 2 of the License, or (at your
// option) any later version.
//
// This file is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
// This file incorporates work covered by the following copyright and
// permission notice:
//
/* anet.c -- Basic TCP socket stuff made a bit less boring
*
* Copyright (c) 2006-2012, Salvatore Sanfilippo <antirez at gmail dot com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of Redis 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.
*/
2016-02-16 14:00:55 +01:00
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <netdb.h>
#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include "anet.h"
static void anetSetError(char *err, const char *fmt, ...)
{
va_list ap;
if (!err) return;
va_start(ap, fmt);
vsnprintf(err, ANET_ERR_LEN, fmt, ap);
va_end(ap);
}
int anetNonBlock(char *err, int fd)
{
int flags;
2016-02-16 14:00:55 +01:00
/* Set the socket nonblocking.
* Note that fcntl(2) for F_GETFL and F_SETFL can't be
* interrupted by a signal. */
if ((flags = fcntl(fd, F_GETFL)) == -1) {
anetSetError(err, "fcntl(F_GETFL): %s", strerror(errno));
return ANET_ERR;
}
if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
anetSetError(err, "fcntl(F_SETFL,O_NONBLOCK): %s", strerror(errno));
return ANET_ERR;
}
2016-02-16 14:00:55 +01:00
return ANET_OK;
}
int anetTcpNoDelay(char *err, int fd)
{
int yes = 1;
if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (void*)&yes, sizeof(yes)) == -1)
{
anetSetError(err, "setsockopt TCP_NODELAY: %s", strerror(errno));
return ANET_ERR;
}
return ANET_OK;
}
int anetSetSendBuffer(char *err, int fd, int buffsize)
{
if (setsockopt(fd, SOL_SOCKET, SO_SNDBUF, (void*)&buffsize, sizeof(buffsize)) == -1)
{
anetSetError(err, "setsockopt SO_SNDBUF: %s", strerror(errno));
return ANET_ERR;
}
return ANET_OK;
}
int anetTcpKeepAlive(char *err, int fd)
{
int yes = 1;
if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void*)&yes, sizeof(yes)) == -1) {
anetSetError(err, "setsockopt SO_KEEPALIVE: %s", strerror(errno));
return ANET_ERR;
}
return ANET_OK;
}
2016-02-16 14:00:55 +01:00
static int anetCreateSocket(char *err, int domain)
{
int s, on = 1;
if ((s = socket(domain, SOCK_STREAM, 0)) == -1) {
anetSetError(err, "creating socket: %s", strerror(errno));
return ANET_ERR;
}
/* Make sure connection-intensive things like the redis benckmark
* will be able to close/open sockets a zillion of times */
if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (void*)&on, sizeof(on)) == -1) {
anetSetError(err, "setsockopt SO_REUSEADDR: %s", strerror(errno));
return ANET_ERR;
}
return s;
}
#define ANET_CONNECT_NONE 0
#define ANET_CONNECT_NONBLOCK 1
2016-02-16 14:00:55 +01:00
static int anetTcpGenericConnect(char *err, char *addr, char *service, int flags)
{
int s;
2016-02-16 14:00:55 +01:00
struct addrinfo gai_hints;
struct addrinfo *gai_result, *p;
int gai_error;
gai_hints.ai_family = AF_UNSPEC;
gai_hints.ai_socktype = SOCK_STREAM;
gai_hints.ai_protocol = 0;
gai_hints.ai_flags = 0;
gai_hints.ai_addrlen = 0;
gai_hints.ai_addr = NULL;
gai_hints.ai_canonname = NULL;
gai_hints.ai_next = NULL;
gai_error = getaddrinfo(addr, service, &gai_hints, &gai_result);
if (gai_error != 0) {
anetSetError(err, "can't resolve %s: %s", addr, gai_strerror(gai_error));
return ANET_ERR;
2016-02-16 14:00:55 +01:00
}
for (p = gai_result; p != NULL; p = p->ai_next) {
if ((s = anetCreateSocket(err, p->ai_family)) == ANET_ERR)
continue;
2016-02-16 14:00:55 +01:00
if (flags & ANET_CONNECT_NONBLOCK) {
if (anetNonBlock(err,s) != ANET_OK)
return ANET_ERR;
}
2016-02-16 14:00:55 +01:00
if (connect(s, p->ai_addr, p->ai_addrlen) >= 0) {
freeaddrinfo(gai_result);
return s;
2016-02-16 14:00:55 +01:00
}
if (errno == EINPROGRESS && (flags & ANET_CONNECT_NONBLOCK)) {
freeaddrinfo(gai_result);
return s;
}
anetSetError(err, "connect: %s", strerror(errno));
close(s);
}
2016-02-16 14:00:55 +01:00
freeaddrinfo(gai_result);
return ANET_ERR;
}
2016-02-16 14:00:55 +01:00
int anetTcpConnect(char *err, char *addr, char *service)
{
2016-02-16 14:00:55 +01:00
return anetTcpGenericConnect(err,addr,service,ANET_CONNECT_NONE);
}
2016-02-16 14:00:55 +01:00
int anetTcpNonBlockConnect(char *err, char *addr, char *service)
{
2016-02-16 14:00:55 +01:00
return anetTcpGenericConnect(err,addr,service,ANET_CONNECT_NONBLOCK);
}
/* Like read(2) but make sure 'count' is read before to return
* (unless error or EOF condition is encountered) */
int anetRead(int fd, char *buf, int count)
{
int nread, totlen = 0;
while(totlen != count) {
nread = read(fd,buf,count-totlen);
if (nread == 0) return totlen;
if (nread == -1) return -1;
totlen += nread;
buf += nread;
}
return totlen;
}
/* Like write(2) but make sure 'count' is read before to return
* (unless error is encountered) */
int anetWrite(int fd, char *buf, int count)
{
int nwritten, totlen = 0;
while(totlen != count) {
nwritten = write(fd,buf,count-totlen);
if (nwritten == 0) return totlen;
if (nwritten == -1) return -1;
totlen += nwritten;
buf += nwritten;
}
return totlen;
}
static int anetListen(char *err, int s, struct sockaddr *sa, socklen_t len) {
2016-02-16 14:00:55 +01:00
if (sa->sa_family == AF_INET6) {
int on = 1;
setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on));
}
if (bind(s,sa,len) == -1) {
anetSetError(err, "bind: %s", strerror(errno));
close(s);
return ANET_ERR;
}
/* Use a backlog of 512 entries. We pass 511 to the listen() call because
* the kernel does: backlogsize = roundup_pow_of_two(backlogsize + 1);
* which will thus give us a backlog of 512 entries */
if (listen(s, 511) == -1) {
anetSetError(err, "listen: %s", strerror(errno));
close(s);
return ANET_ERR;
}
return ANET_OK;
}
2016-02-16 14:00:55 +01:00
int anetTcpServer(char *err, char *service, char *bindaddr, int *fds, int nfds)
{
int s;
2016-02-16 14:00:55 +01:00
int i = 0;
struct addrinfo gai_hints;
struct addrinfo *gai_result, *p;
int gai_error;
gai_hints.ai_family = AF_UNSPEC;
gai_hints.ai_socktype = SOCK_STREAM;
gai_hints.ai_protocol = 0;
gai_hints.ai_flags = AI_PASSIVE;
gai_hints.ai_addrlen = 0;
gai_hints.ai_addr = NULL;
gai_hints.ai_canonname = NULL;
gai_hints.ai_next = NULL;
gai_error = getaddrinfo(bindaddr, service, &gai_hints, &gai_result);
if (gai_error != 0) {
anetSetError(err, "can't resolve %s: %s", bindaddr, gai_strerror(gai_error));
return ANET_ERR;
2016-02-16 14:00:55 +01:00
}
2016-02-16 14:00:55 +01:00
for (p = gai_result; p != NULL && i < nfds; p = p->ai_next) {
if ((s = anetCreateSocket(err, p->ai_family)) == ANET_ERR)
continue;
if (anetListen(err, s, p->ai_addr, p->ai_addrlen) == ANET_ERR) {
continue;
}
fds[i++] = s;
}
2016-02-16 14:00:55 +01:00
freeaddrinfo(gai_result);
return (i > 0 ? i : ANET_ERR);
}
2016-02-16 14:00:55 +01:00
static int anetGenericAccept(char *err, int s, struct sockaddr *sa, socklen_t *len)
{
int fd;
while(1) {
fd = accept(s,sa,len);
if (fd == -1) {
2014-04-25 18:00:58 +02:00
if (errno == EINTR) {
continue;
} else {
anetSetError(err, "accept: %s", strerror(errno));
}
}
break;
}
return fd;
}
2016-02-16 14:00:55 +01:00
int anetTcpAccept(char *err, int s) {
int fd;
2016-02-16 14:00:55 +01:00
struct sockaddr_storage ss;
socklen_t sslen = sizeof(ss);
if ((fd = anetGenericAccept(err, s, (struct sockaddr*)&ss, &sslen)) == ANET_ERR)
return ANET_ERR;
return fd;
}