bionic/libc/inet/bindresvport.c
2009-03-03 19:28:35 -08:00

73 lines
2.4 KiB
C

/*
* Copyright (C) 2008 The Android Open Source Project
* 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.
*
* 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.
*/
#include <errno.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <unistd.h>
#define START_PORT 600
#define END_PORT IPPORT_RESERVED
#define NUM_PORTS (END_PORT - START_PORT)
int bindresvport(int sd, struct sockaddr_in *sin)
{
static short port;
struct sockaddr_in sin0;
int nn, ret;
if (sin == NULL) {
sin = &sin0;
memset( sin, 0, sizeof *sin );
sin->sin_family = AF_INET;
} else if (sin->sin_family != AF_INET) {
errno = EPFNOSUPPORT;
return -1;
}
if (port == 0) {
port = START_PORT + (getpid() % NUM_PORTS);
}
for (nn = NUM_PORTS; nn > 0; nn--, port++)
{
if (port == END_PORT)
port = START_PORT;
sin->sin_port = htons(port);
do {
ret = bind(sd, (struct sockaddr*)sin, sizeof(*sin));
} while (ret < 0 && errno == EINTR);
if (!ret)
break;
}
return ret;
}