/*---------------------------------------------------------------
* Copyright (c) 1999,2000,2001,2002,2003
* The Board of Trustees of the University of Illinois
* All Rights Reserved.
*---------------------------------------------------------------
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software (Iperf) and associated
* documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute,
* sublicense, and/or sell copies of the Software, and to permit
* persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and
* the following disclaimers.
*
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimers in the documentation and/or other materials
* provided with the distribution.
*
*
* Neither the names of the University of Illinois, NCSA,
* nor the names of its contributors may be used to endorse
* or promote products derived from this Software without
* specific prior written permission.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE CONTIBUTORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
* ________________________________________________________________
* National Laboratory for Applied Network Research
* National Center for Supercomputing Applications
* University of Illinois at Urbana-Champaign
* http://www.ncsa.uiuc.edu
* ________________________________________________________________
*
* socket.c
* by Mark Gates <mgates@nlanr.net>
* -------------------------------------------------------------------
* set/getsockopt and read/write wrappers
* ------------------------------------------------------------------- */
#include "headers.h"
#include "util.h"
#ifdef __cplusplus
extern "C" {
#endif
/* -------------------------------------------------------------------
* If inMSS > 0, set the TCP maximum segment size for inSock.
* Otherwise leave it as the system default.
* ------------------------------------------------------------------- */
const char warn_mss_fail[] = "\
WARNING: attempt to set TCP maxmimum segment size to %d failed.\n\
Setting the MSS may not be implemented on this OS.\n";
const char warn_mss_notset[] =
"WARNING: attempt to set TCP maximum segment size to %d, but got %d\n";
void setsock_tcp_mss (int inSock, int inMSS) {
#ifdef TCP_MAXSEG
int rc;
int newMSS;
Socklen_t len;
assert(inSock != INVALID_SOCKET);
if (inMSS > 0) {
/* set */
newMSS = inMSS;
len = sizeof(newMSS);
rc = setsockopt(inSock, IPPROTO_TCP, TCP_MAXSEG, (char*) &newMSS, len);
if (rc == SOCKET_ERROR) {
fprintf(stderr, warn_mss_fail, newMSS);
return;
}
/* verify results */
rc = getsockopt(inSock, IPPROTO_TCP, TCP_MAXSEG, (char*) &newMSS, &len);
WARN_errno(rc == SOCKET_ERROR, "getsockopt TCP_MAXSEG");
if (newMSS != inMSS) {
fprintf(stderr, warn_mss_notset, inMSS, newMSS);
}
}
#endif
} /* end setsock_tcp_mss */
/* -------------------------------------------------------------------
* returns the TCP maximum segment size
* ------------------------------------------------------------------- */
int getsock_tcp_mss (int inSock) {
int theMSS = -1;
#ifdef TCP_MAXSEG
int rc;
Socklen_t len;
assert(inSock >= 0);
/* query for MSS */
len = sizeof(theMSS);
rc = getsockopt(inSock, IPPROTO_TCP, TCP_MAXSEG, (char*)&theMSS, &len);
WARN_errno(rc == SOCKET_ERROR, "getsockopt TCP_MAXSEG");
#endif
return theMSS;
} /* end getsock_tcp_mss */
/* -------------------------------------------------------------------
* Attempts to reads n bytes from a socket.
* Returns number actually read, or -1 on error.
* If number read < inLen then we reached EOF.
*
* from Stevens, 1998, section 3.9
* ------------------------------------------------------------------- */
ssize_t readn (int inSock, void *outBuf, size_t inLen) {
size_t nleft;
ssize_t nread;
char *ptr;
assert(inSock >= 0);
assert(outBuf != NULL);
assert(inLen > 0);
ptr = (char*) outBuf;
nleft = inLen;
while (nleft > 0) {
nread = read(inSock, ptr, nleft);
if (nread < 0) {
if (errno == EINTR)
nread = 0; /* interupted, call read again */
else
return -1; /* error */
} else if (nread == 0)
break; /* EOF */
nleft -= nread;
ptr += nread;
}
return(inLen - nleft);
} /* end readn */
/* -------------------------------------------------------------------
* Similar to read but supports recv flags
* Returns number actually read, or -1 on error.
* If number read < inLen then we reached EOF.
* from Stevens, 1998, section 3.9
* ------------------------------------------------------------------- */
int recvn (int inSock, char *outBuf, int inLen, int flags) {
int nleft;
int nread = 0;
char *ptr;
assert(inSock >= 0);
assert(outBuf != NULL);
assert(inLen > 0);
ptr = outBuf;
nleft = inLen;
#if (HAVE_DECL_MSG_PEEK)
if (flags & MSG_PEEK) {
while (nleft != nread) {
nread = recv(inSock, ptr, nleft, flags);
switch (nread) {
case SOCKET_ERROR :
// Note: use TCP fatal error codes even for UDP
if (FATALTCPREADERR(errno)) {
WARN_errno(1, "recvn peek");
nread = -1;
goto DONE;
}
#ifdef HAVE_THREAD_DEBUG
WARN_errno(1, "recvn peek non-fatal");
#endif
break;
case 0:
#ifdef HAVE_THREAD_DEBUG
WARN(1, "recvn peek peer close");
#endif
goto DONE;
break;
default :
break;
}
}
} else
#endif
{
while (nleft > 0) {
#if (HAVE_DECL_MSG_WAITALL)
nread = recv(inSock, ptr, nleft, MSG_WAITALL);
#else
nread = recv(inSock, ptr, nleft, 0);
#endif
switch (nread) {
case SOCKET_ERROR :
// Note: use TCP fatal error codes even for UDP
if (FATALTCPREADERR(errno)) {
WARN_errno(1, "recvn");
nread = -1;
goto DONE;
}
#ifdef HAVE_THREAD_DEBUG
WARN_errno(1, "recvn non-fatal");
#endif
break;
case 0:
#ifdef HAVE_THREAD_DEBUG
WARN(1, "recvn peer close");
#endif
nread = inLen - nleft;
goto DONE;
break;
default :
nleft -= nread;
ptr += nread;
break;
}
nread = inLen - nleft;
}
}
DONE:
return(nread);
} /* end readn */
/* -------------------------------------------------------------------
* Attempts to write n bytes to a socket.
* returns number actually written, or -1 on error.
* number written is always inLen if there is not an error.
*
* from Stevens, 1998, section 3.9
* ------------------------------------------------------------------- */
int writen (int inSock, const void *inBuf, int inLen, int *count) {
int nleft;
int nwritten;
const char *ptr;
assert(inSock >= 0);
assert(inBuf != NULL);
assert(inLen > 0);
assert(count != NULL);
ptr = (char*) inBuf;
nleft = inLen;
nwritten = 0;
*count = 0;
while (nleft > 0) {
nwritten = write(inSock, ptr, nleft);
(*count)++;
switch (nwritten) {
case SOCKET_ERROR :
if (!(errno == EINTR) || (errno == EAGAIN) || (errno == EWOULDBLOCK)) {
nwritten = inLen - nleft;
WARN_errno(1, "writen fatal");
goto DONE;
}
break;
case 0:
// write timeout - retry
break;
default :
nleft -= nwritten;
ptr += nwritten;
break;
}
nwritten = inLen - nleft;
}
DONE:
return (nwritten);
} /* end writen */
#ifdef __cplusplus
} /* end extern "C" */
#endif